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Technical publications 2017

Burner air-fuel ratio monitoring in large pulverised-fuel boilers using advanced sensors : case study of a 660 MWe coal-fired power plant

Blondeau, Julien, Auteur; Rijmenans, Laurent, Auteur; Annendijck, Jurgen, Auteur; Heyer, A., Auteur; Martensen, E., Auteur; Popin, I., Auteur; Wijittongruang, A., Auteur; Holub, L., Auteur; Laborelec

Published in : Preprint submitted to Thermal Science and Engineering Progress

Résumé : In this paper, a novel methodology is proposed for the online monitoring of the air-fuel ratio in large pulverised-fuel boilers at the burner level. Using standard measurements, this parameter can only be estimated, as the fuel distribution between burners is generally missing. The detailed air
flow distribution to the burners can also be unknown depending on the available measurements. An accurate control of local and global air-fuel ratios is however crucial in terms of boiler efficiency and various pollutant emission reductions, leading to lower overall operational cost, improved performance and increased fuel and load flexibility. It is here proposed to combine two advanced techniques to quantify air and fuel flow rates per burner: microwave probes for fuel particles and smart soft sensors for air. When combined, those measurements allow for the calculation of the local air-fuel ratios. The proposed methodology was successfully applied to the boiler of a 660 MWe coal-fired power plant. While the burner equivalence ratios predicted by the standard equipments were in the range 0.9 - 1.05, it was shown that the actual range was significantly broader (0.65 - 1.25). Looking at the averaged ratios per burner level, it was concluded that the expected values were globally overestimated compared to the measured values (> +14%). The performed air flow measurements were also used to partially tune the combustion process by solving hardware and software issues. Oxygen, flue gas flow rate, temperature and NOx imbalances at the outlet of the furnace were significantly reduced.

Characterization of soiling on PV modules in the Atacama Desert

Olivares, Douglas, Auteur; Ferrada, Pablo, Auteur; de Matos, Camila, Auteur; Marzo, Aitor, Auteur; Cabrera, Enrique, Auteur; Portillo, Carlos, Auteur; Llanos, Jaime, Auteur; Laborelec

Published in : Energy Procedia Vol. 124, Septembre 2017, p. 547-553

Résumé : The soling can negatively affect the performance of photovoltaic systems. We studied the species, which deposit on photovoltaic (PV) modules in northern Chile (Atacama Desert). The environmental conditions are the base for the interaction of dust particles and the module’s surfaces. We considered 4 locations for the study. We determined that the particle size of the dust to deposit on PV modules is smaller than 63 μm for all the selected sites. However, the morphology varies from place to place influencing optical response of the modules. After 4 months dust accumulation the transmittance of PV glass reduced by 55%.

Corrosion Testing of a Heat Treated 316 L Functional Part Produced by Selective Laser Melting

De Bruycker, Evy, Auteur; Montero Sistiaga, Maria L., Auteur; Thielemans, Fabien, Auteur; Vanmeenseel, Kim, Auteur; Laborelec

Published in : Materials Sciences and Applications, Vol. 8, N. 3, March 2017, pp. 223-233

Résumé : Selective Laser Melting (SLM) shows a big potential among metal additive manufacturing (AM) technologies. However, the large thermal gradients and the local melting and solidification processes of SLM result in the presence of a significant amount of residual stresses in the as built parts. These internal stresses will not only affect mechanical properties, but also increase the risk of Stress Corrosion Cracking (SCC). A twister used in an air extraction pump of a condenser to create a swirl in the water, was chosen as a candidate component to be produced by SLM in 316 L stainless steel. Since the main expected damage mechanism of this component in service is corrosion, corrosion tests were carried out on an as-built twister as well as on heat treated components. It was shown that a low temperature heat treatment at 450˚C had only a limited effect on the residual stress reduction and concomitant corrosion properties, while the internal stresses were significantly reduced when a high temperature heat treatment at 950˚C was applied. Furthermore, a specific stress corrosion sensitivity test proved to be a useful tool to evaluate the internal stress distribution in a specific component.

Cyber-security in hydro plants : implementation at a 1 GW pumped-storage scheme

Voigt, Wolfgang, Auteur; Menting, Jos, Auteur; Bucher, Ralf, Auteur; Laborelec

Published in Hydro 2017 : Shaping the Future of Hydropower (09/10/2017)

Dissimilar metal welds between 9Cr creep strength enhanced ferritic steel and advanced stainless steels--creep rupture test results and microstructural investigations

Huysmans, Staf, Auteur; Vekeman, Johan , Auteur; Hautfenne, C, Auteur; Laborelec

Published in Welding in the World Vol. 61 - N. 2 (March 2017). - 341-350

Résumé: Modern and future power plants will use more complex materials to withstand the higher steam temperatures and pressures as well as thermal cycling. As such, dissimilar metal welds (DMWs) will be more widespread in new design than before and will need to demonstrate resistance to combinations of severe creep, corrosion/oxidation, and low cycle fatigue. The DMWs between different steels or alloys are an underestimated topic. Experienced and documented premature failures reveal the criticality of DMWs. This study focused on the DMWs between 9Cr martensitic creep strength enhanced ferritic steels and advanced austenitic stainless steels. Two collaborative projects related to 18%Cr and 25%Cr austenitic creep resisting stainless steel delivered data concerning base metal characterization and weldability of similar and dissimilar welding. The specific features of dissimilar welding are further approached in more detail in this analysis. Two main methodologies, i.e., direct welding and buttering techniques using different filler metals were investigated and characterized via uniaxial creep rupture testing and metallographic examination particularly focusing on the fusion line carbide formation and morphology. For the limited exposure times of 10 kh in this project, the results show that aligned and coarse type I carbide formation is occurring at the 9Cr fusion line between A617 type weld metal. The selection of P87 or A82 type filler metals demonstrated isolated to partly aligned carbides, respectively, at the fusion line. To mitigate the risk to corrosion and achieve a marginal increase in creep performance, buttering techniques are recommended.

L'hydrogène au long cours

Mertens, Jan, Auteur; Hillegeer, Caroline, Auteur; Lepaumier, Hélène, Auteur; Makhloufi, Camel, Auteur; Baraton, Laurent, Auteur; Moretti, Isabelle, Auteur; Laborelec

Published in Pour la Science CS2018 (Mars 2018). - 22-23

Résumé: Comment transporter les énergies renouvelables ? En les convertissant en hydrogène vert, un composé que l’on peut ensuite embarquer, par exemple, dans des bateaux. Sous quelle forme convertir cet hydrogène ?

Influence of heat treatments and build orientation on the creep strength of additive manufactured IN718

Hautfenne, C, Auteur; Nardone, Steve, Auteur; De Bruycker, Evy, Auteur; Laborelec

Published in 4th International ECCC Creep & Fracture Conference (10/09/2017)

Résumé : Metal 3D Printing, also known as Additive Manufacturing, is currently reaching its maturity in high-end industrial applications. A growing consolidation of the Additive Manufacturing industry has been observed the last years in the industrial sector, especially for aerospace, aviation and more recently in the energy sector. When additive manufactured metals are to be used in power generation equipment, it is important to assure their mechanical robustness including sufficient creep strength. Selective laser melting (SLM) technology, based on local fusion of a powder bed, is currently one of the main additive manufacturing techniques for metallic parts. Few publications provide comprehensive results on creep behaviour of nickel-based superalloys produced by SLM. Several IN718 samples were produced by SLM and subjected to different heat treatments. Afterwards short term creep tests (up to 2500h) were carried out on vertically and horizontally built SLM samples. The results were compared with master curves for conventionally produced IN718 material. It was demonstrated that by using the appropriate heat treatment, the short term creep properties of additive manufactured IN718 material can reach the master curve of conventionally produced IN718.

Prevention of Mist Formation in Amine Based Carbon Capture : Field Testing Using a Wet ElectroStatic Precipitator (WESP) and a Gas-Gas Heater (GGH)

Mertens, Jan, Auteur; Khakharia, Purvil, Auteur; Rogiers, Pieter, Auteur; Blondeau, Julien, Auteur; Lepaumier, Hélène, Auteur; Goetheer, Earl, Auteur; Schallert, Bernd, Auteur; Schaber, Karlheinz, Auteur; Moretti, Isabelle, Auteur; Laborelec

Published in : Energy Procedia, Volume 114, July 2017, Pages 987-999

Résumé : This study presents the results of two field tests that aimed at evaluating two countermeasures (WESP and GGH) to avoid acid mist formation. A WESP is shown to be very efficient for the removal of nuclei from the flue gas (100% efficient) and thus can prevent aerosol formation inside an amine based absorber. This is however only valid in the absence of SO2 in the flue gas entering the WESP. A decreasing WESP efficiency is noted in the presence of SO2 with increasing voltages as a result of newly formed aerosols inside the WESP. This implies that no or very low levels of SO2 should be present in the flue gas entering the WESP. Since most of the amine carbon capture installations have a pre-scrubber (usually using NaOH to remove residual SO2 in the flue gas leaving the power plant's Flue Gas Desulphurisation) in front of their amine absorber, the WESP must be installed behind this pre-scrubber and not in front of it. Having a Gas-Gas Heater (or any type of flue gas cooling such as a Low Temperature Heat Exchanger) installed upstream of the wet scrubbing may prevent homogenous nucleation and thus prevent the conversion of H2SO4 into sulfuric acid aerosols and consequently mist formation issues in the amine based carbon capture installation. Which option to choose amongst the two countermeasures presented in this study will depend on whether a new built installation is being considered or whether a carbon capture is planned as a retrofit into an existing installation.

A quick on-line state of health estimation method for Li-ion battery with incremental capacity curves processed by Gaussian filter

Li, Y., Auteur; Abdel-Monem, Mohamed, Auteur; Gopalakrishnan, Rahul, Auteur; Berecibar, Maitane, Auteur; Nanini-Maury, Elise, Auteur; Laborelec

Published in : Journal of Power Sources, Volume 373 (January 2018), p. 40-53

Résumé : This paper proposes an advanced state of health (SoH) estimation method for high energy NMC lithium-ion batteries based on the incremental capacity (IC) analysis. IC curves are used due to their ability of detect and quantify battery degradation mechanism. A simple and robust smoothing method is proposed based on Gaussian filter to reduce the noise on IC curves, the signatures associated with battery ageing can therefore be accurately identified. A linear regression relationship is found between the battery capacity with the positions of features of interest (FOIs) on IC curves. Results show that the developed SoH estimation function from one single battery cell is able to evaluate the SoH of other batteries cycled under different cycling depth with less than 2.5% maximum errors, which proves the robustness of the proposed method on SoH estimation. With this technique, partial charging voltage curves can be used for SoH estimation and the testing time can be therefore largely reduced. This method shows great potential to be applied in reality, as it only requires static charging curves and can be easily implemented in battery management system (BMS).

Residential Electricity Tariffs in Europe : Current Situation, Evolution and Impact on Residential Flexibility Markets

Oualmakran, Youssef, Auteur; Espeche, Juan Manuel Espeche, Auteur; Sisinni, Mario, Auteur; Messervey, Thomas, Auteur; Lennard, Zia, Auteur; Laborelec

Published in : Proceedings of the Sustainable Places 2017 (SP2017) Conference, 2017, 1, 973.

Résumé : Residential flexibility (a.k.a demand response) is a key component of smart grids to reduce our carbon footprint, to have reliable power (balance between power and demand, and avoiding congestion) and more affordable electricity tariffs. However, to have a significant participation in the flexibility markets, households needs good price signals. Today, the electricity bill components (volumetric and capacity for both consumption and generation) are evolving and grid services are increasingly more available to households. This is due to the evolution in the energy mix, deployment of new technologies (smart meter roll-out, gradual uptake of electric vehicles, heat pumps and batteries), regional integration (interconnectors and integration of balancing markets) and evolution of society (sharing economy or Peer2peer and ubiquity of smartphones). These trends will have a quantitative impact on the different energy bills in the short term (2020) and longer term. Further investigation is also suggested to go from the qualitative analysis to a better quantitative analysis.

Stray Gassing of Transformer Insulating Oils : Impact of Materials, Oxygen Content, Additives, Incubation Time and Temperature, and Its Relationship to Oxidation Stability

Eeckhoudt, Steve, Auteur; Autru, Stijn, Auteur; Lerat, Luc, Auteur; Laborelec

Published in IEEE Electrical Insulation Magazine Vol. 33 - N. 6 (November/December 2017). - 27-32

Résumé: For many years, dissolved gas analysis (DGA) has been considered worldwide as the most important technique for evaluating the state of health of oil-filled power transformers. Based on regular analysis and trending of the dissolved gases extracted from insulating oil samples, an assessment can be made whether internal transformer abnormalities are present and how critical these abnormalities are [1], [2]. The article examines the impact of temperature, oxygen, antioxidant, and incubation time on stray gassing of unused and in-service mineral oils and the relationship of gassing to oxidation stability.

Ten years of experience with 3 kHz water tree test

Burceanu, Monica, Auteur; De Clerck, Quentin, Auteur; Tits, Yvan, Auteur; Laborelec

Published in : 24th International Conference & Exhibition on Electricity Distribution (CIRED), 12-15 June 2017, p. 468-471

Résumé : Electrical trees and degradations due to water trees (WTs) are one of the major causes of premature ageing and failure of extruded medium voltage cables. The estimation of WTs resistance and lifetime of cable insulations represents all over the world an important issue for cable owners. The reproduction of WTs in a laboratory in a reasonable duration is highly helpful not only to provide advices for specifications and purchasers but also to plan the maintenance programs. A lot of accelerated tests have already been developed on flat samples with defects created by abrasive study or on a bulk sample using needles. Compared to these methods, the 3 kHz method is highly appreciated. Since its development in 2006, more than 200 cable samples have been tested by Laborelec according to the 3 kHz method. This study describes some of the most interesting results obtained during the last 10 years with this method.
Langues : Anglais (eng)

Understanding and Modelling the Effect of Dissolved Metals on Solvent Degradation in Post Combustion CO2 Capture Based on Pilot Plant Experience

Dhingra, Sanjana, Auteur; Khakharia, Purvil, Auteur; Rieder, Alexander, Auteur; Cousins, Ashleigh, Auteur; Reynolds, Alicia, Auteur; Knudsen, Jacob, Auteur; Andersen, Jimmy, Auteur; Irons, Robin, Auteur; Mertens, Jan, Auteur; Abu Zahra, Mohammad, Auteur; Van Os, Peter, Auteur; Goetheer, Earl, Auteur; Laborelec

Published in : Energies, Vol. 10, n°5, MDPI, 2017.

Résumé : Oxidative degradation is a serious concern for upscaling of amine-based carbon capture technology. Different kinetic models have been proposed based on laboratory experiments, however the kinetic parameters included are limited to those relevant for a lab-scale system and not a capture plant. Besides, most of the models fail to recognize the catalytic effect of metals. The objective of this work is to develop a representative kinetic model based on an apparent auto-catalytic reaction mechanism between solvent degradation, corrosion and ammonia emissions. Measurements from four different pilot plants: (i) EnBW’s plant at Heilbronn, Germany (ii) TNO’s plant at Maasvlakte, The Netherlands; (iii) CSIRO’s plants at Loy Yang and Tarong, Australia and (iv) DONG Energy’s plant at Esbjerg, Denmark are utilized to propose a degradation kinetic model for 30 wt % ethanolamine (MEA) as the capture solvent. The kinetic parameters of the model were regressed based on the pilot plant campaign at EnBW. The kinetic model was validated by comparing it with the measurements at the remaining pilot campaigns. The model predicted the trends of ammonia emissions and metal concentration within the same order of magnitude. This study provides a methodology to establish a quantitative approach for predicting the onset of unacceptable degradation levels which can be further used to devise counter-measure strategies such as reclaiming and metal removal.

Technical publications 2016

Advanced characterization of available not conventional mediterranean biomass solid fuels for ash related issues in thermal processes

De Fusco, L., Auteur; Jeanmart, H., Auteur; Contino, Francesco, Auteur; Blondeau, Julien, Auteur; Laborelec

Published in : Chemical Engineering Transactions, Vol. 50, June 2016, pp. 229-234

Résumé : According to the European Biomass Association, bioenergy represents about 60% of the EU's total consumption of renewables. The EERA Bioenergy, section of the European Energy Research Alliance, indicates that agricultural residues and non-food crops should be used at farm- and village-scales, while low quality biomass and waste could be used for medium- and large-scale power and CHP plants. Among the barriers that hamper the efficient processing of solid fuels in thermal processes, such as combustion and gasification, ash related issues are still challenging for plant operators. These issues include agglomeration in fluidized bed combustion, slag formation, and fouling of convective heat exchangers. Furthermore, advanced characterization methods for solid biomass fuels, especially predictive approaches for ash related issues, are not fully developed. Consequently, the use of unconventional biomass solid fuels is limited because of operating risks. In addition, the availability of the detailed chemical analyses of unconventional fuels is often limited. In this investigation, a validated fuel characterization tool to define the agglomeration - slagging propensity of biomass fuels for their use in thermal processes, is applied to an advanced database of mediterranean (Greece, Italy, Spain) opportunity fuels. The database is built by means of an extensive literature review, including the detailed ash chemical compositions. The input of the tool is the specific fuel ash chemical composition, and the output is the agglomeration - slagging propensity computed as a parameter in the range (0-100). In this work it is shown that a high ash fusion temperature (from the Ash Fusion Test) is a necessary but not sufficient condition to low agglomeration and slagging in combustion applications. Among the fuels analyzed, wood, shrubs and citrus industry agro-residues evidenced a low-to-medium median propensity to agglomerate and slag, contrarily to the high propensity of agro-residues (various), wine industry residues, and crops. About 20 opportunity fuels, with low-to-medium agglomeration and slagging propensity and for which environmental, economic and social sustainability has to be further explored, are suggested for thermal applications. Some countermeasures to efficiently process the more challenging fuels are mentioned, including the use of specific combustion additives.

Ash Characterization of Four Residual Wood Fuels in a 100 kWth Circulating Fluidized Bed Reactor Including the Use of Kaolin and Halloysite Additives

De Fusco, L., Auteur; Defoort, F., Auteur; Rajczyk, R., Auteur; Jeanmart, H., Auteur; Blondeau, Julien, Auteur; Contino, Francesco, Auteur; Laborelec

Published in : Energy Fuels, Vol. 30 - N. 10, pp. 8304-8315
10.1021/acs.energyfuels.6b01784.

Résumé : Solid biomass ash related issues and adequate fuel characterization, especially for fuels with similar thermochemical properties, are still major challenges in combustion. As a consequence, the fuel switching and the valorization of unconventional available fuels are hazardous. An integrated strategy to characterize biomass fuels for ash related issues is applied to four residual woody fuels, namely, a mesquite wood mixture, rubberwood, an invader bush wood, and bamboo wood. The characterization is performed with detailed analyses including (i) ash composition, (ii) ash association forms by leaching, (iii) recently reviewed predictive correlations, (iv) thermochemical equilibrium computations to predict the ash phases formed as a function of the combustion parameters and with the use of a state-of-the-art oxide database, and (v) experimental testing in a 100 kWth circulating fluidized bed pilot reactor (CFB100). The CFB100 testing allowed investigation of the fuel ash cycle including fly ash recirculation, agglomeration and fouling tendencies, and the use of halloysite and kaolin mineral additives. Among the four fuels, bamboo evidenced the higher agglomeration trend, which increased when reducing the additive. With respect to the other fuels, rubberwood seems to have a slightly higher tendency to initiate the coating-induced agglomeration mechanism. Concerning fouling, the mesquite mixture wood is more prone to deposition, mainly because of the formation of Ca-based deposits, while for the other three fuels, ash partitioning shows that the majority of reactive alkali metals fed to the pilot is accumulated in the bottom ash and circulating material. The novel integrated strategy is successfully applied for advanced solid biomass fuel characterization for combustion.

Burner air-fuel ratio monitoring in large pulverised-fuel boilers using advanced sensors : case study of a 660 MWe coal-fired power plant

Blondeau, Julien, Auteur; Rijmenans, Laurent, Auteur; Annendijck, Jurgen, Auteur; Heyer, A., Auteur; Martensen, E., Auteur; Popin, I., Auteur; Wijittongruang, A., Auteur; Holub, L., Auteur; Laborelec

Published in : Preprint submitted to Thermal Science and Engineering Progress

Résumé : In this paper, a novel methodology is proposed for the online monitoring of the air-fuel ratio in large pulverised-fuel boilers at the burner level. Using standard measurements, this parameter can only be estimated, as the fuel distribution between burners is generally missing. The detailed air
flow distribution to the burners can also be unknown depending on the available measurements. An accurate control of local and global air-fuel ratios is however crucial in terms of boiler efficiency and various pollutant emission reductions, leading to lower overall operational cost, improved performance and increased fuel and load flexibility. It is here proposed to combine two advanced techniques to quantify air and fuel flow rates per burner: microwave probes for fuel particles and smart soft sensors for air. When combined, those measurements allow for the calculation of the local air-fuel ratios. The proposed methodology was successfully applied to the boiler of a 660 MWe coal-fired power plant. While the burner equivalence ratios predicted by the standard equipments were in the range 0.9 - 1.05, it was shown that the actual range was significantly broader (0.65 - 1.25). Looking at the averaged ratios per burner level, it was concluded that the expected values were globally overestimated compared to the measured values (> +14%). The performed air flow measurements were also used to partially tune the combustion process by solving hardware and software issues. Oxygen, flue gas flow rate, temperature and NOx imbalances at the outlet of the furnace were significantly reduced.

Characterization of Sunflower Husks Fouling in a Drop Tube Furnace : Comparison of Deposits with H3PO4, CaCO3 and Al2Si2O5(OH)4 Additives

De Fusco, L., Auteur; Blondeau, Julien, Auteur; Jeanmart, H., Auteur; Contino, Francesco, Auteur; Laborelec

Published in : 24th "Journées d'Etude" of the Belgian Section of the Combustion Institute (May 19-20, 2016)

Characterization of soiling on PV modules in the Atacama Desert

Olivares, Douglas, Auteur; Ferrada, Pablo, Auteur; de Matos, Camila, Auteur; Marzo, Aitor, Auteur; Cabrera, Enrique, Auteur; Portillo, Carlos, Auteur; Llanos, Jaime, Auteur; Laborelec

Published in : Energy Procedia Vol. 124, Septembre 2017, p. 547-553
10.1016/j.egypro.2017.09.263.

Résumé : The soling can negatively affect the performance of photovoltaic systems. We studied the species, which deposit on photovoltaic (PV) modules in northern Chile (Atacama Desert). The environmental conditions are the base for the interaction of dust particles and the module’s surfaces. We considered 4 locations for the study. We determined that the particle size of the dust to deposit on PV modules is smaller than 63 μm for all the selected sites. However, the morphology varies from place to place influencing optical response of the modules. After 4 months dust accumulation the transmittance of PV glass reduced by 55%.

The correlation between elongation at break and thermal decomposition of aged EPDM cable polymer

Sarac, T., Auteur; Devaux, J., Auteur; Quievy, Nicolas, Auteur; Laborelec

Published in : Radiation Physics and Chemistry, vol. 132, March 2017, pages 8-12

Résumé : The effect of simultaneous thermal and gamma irradiation ageing on the mechanical and physicochemical properties of industrial EPDM was investigated. Accelerated ageing, covering a wide range of dose rates, doses and temperatures, was preformed in stagnant air on EPDM polymer samples extracted from the cables in use in the Belgian nuclear power plants. The mechanical properties, ultimate tensile stress and elongation at break, are found to exhibit the strong dependence on the dose, ageing temperature and dose rate. The thermal decomposition of aged polymer is observed to be the dose dependent when thermogravimetry test is performed under air atmosphere. No dose dependence is observed when thermal decomposition is performed under nitrogen atmosphere. The thermal decomposition rates are found to fully mimic the reduction of elongation at break for all dose rates and ageing temperatures. This effect is argued to be the result of thermal and radiation mediated oxidation degradation process.

Corrosion Testing of a Heat Treated 316 L Functional Part Produced by Selective Laser Melting

De Bruycker, Evy, Auteur; Montero Sistiaga, Maria L., Auteur; Thielemans, Fabien, Auteur; Vanmeenseel, Kim, Auteur; Laborelec

Published in : Materials Sciences and Applications, Vol. 8, N. 3, March 2017, pp. 223-233
10.4236/msa.2017.83015.

Résumé : Selective Laser Melting (SLM) shows a big potential among metal additive manufacturing (AM) technologies. However, the large thermal gradients and the local melting and solidification processes of SLM result in the presence of a significant amount of residual stresses in the as built parts. These internal stresses will not only affect mechanical properties, but also increase the risk of Stress Corrosion Cracking (SCC). A twister used in an air extraction pump of a condenser to create a swirl in the water, was chosen as a candidate component to be produced by SLM in 316 L stainless steel. Since the main expected damage mechanism of this component in service is corrosion, corrosion tests were carried out on an as-built twister as well as on heat treated components. It was shown that a low temperature heat treatment at 450˚C had only a limited effect on the residual stress reduction and concomitant corrosion properties, while the internal stresses were significantly reduced when a high temperature heat treatment at 950˚C was applied. Furthermore, a specific stress corrosion sensitivity test proved to be a useful tool to evaluate the internal stress distribution in a specific component.

Cost and revenue breakdown for a pumped hydroelectric energy storage installation in Belgium

Steimes, J., Auteur; Al Zohbi, G., Auteur; Hendrick, P., Auteur; Haut, Bertrand, Auteur; Doucement, Sylvain, Auteur; Laborelec

Published in : Livre Sustainable Hydraulics in the Era of Global Change / Erpicum, Sébastien (07/07/2016) / 978-1-13-802977-4

Résumé: The technical and economic feasibility of Pumped Hydroelectric Energy Storage (PHES) is increasingly under discussion in Belgium and worldwide. The important initial capital cost, a barrier to the use of PHES systems, could be counterbalanced by using pre-existing installations (as mines or quarries). However, it is necessary to have an estimation of the costs and revenues breakdown of these installations in order to optimise the number and the type of components that will be installed. This paper presents the cost and revenue breakdown for a PHES installation to be installed in Belgium, more specifically in theWalloon region. It presents the division of the plant into sub-parts for which the investment costs are modelled (reservoirs, electrical lines, etc.). An optimisation of the revenue sources available to PHES plants in Belgium is then presented. This helps to optimise the utilisation of the plant. Operation and Maintenance costs are finally taken into account to build a financial analysis of the investment. These computations help to estimate the most promising installation for a dedicated site. This is then illustrated as a conclusion on a case study of a PHES site of 4MW and 20MWh installed in a quarry and a mine. Results showthat the installation in the mine seems more promising, but specific additional startup costs will have to be taken into account in futures works.

Cyber-security in hydro plants : implementation at a 1 GW pumped-storage scheme

Voigt, Wolfgang, Auteur; Menting, Jos, Auteur; Bucher, Ralf, Auteur; Laborelec

Published in : Hydro 2017 : Shaping the Future of Hydropower (09/10/2017)

Dissimilar metal welds between 9Cr creep strength enhanced ferritic steel and advanced stainless steels--creep rupture test results and microstructural investigations

Huysmans, Staf, Auteur; Vekeman, Johan , Auteur; Hautfenne, C, Auteur; Laborelec

Published in Welding in the World Vol. 61 - N. 2 (March 2017). - 341-350

Résumé: Modern and future power plants will use more complex materials to withstand the higher steam temperatures and pressures as well as thermal cycling. As such, dissimilar metal welds (DMWs) will be more widespread in new design than before and will need to demonstrate resistance to combinations of severe creep, corrosion/oxidation, and low cycle fatigue. The DMWs between different steels or alloys are an underestimated topic. Experienced and documented premature failures reveal the criticality of DMWs. This study focused on the DMWs between 9Cr martensitic creep strength enhanced ferritic steels and advanced austenitic stainless steels. Two collaborative projects related to 18%Cr and 25%Cr austenitic creep resisting stainless steel delivered data concerning base metal characterization and weldability of similar and dissimilar welding. The specific features of dissimilar welding are further approached in more detail in this analysis. Two main methodologies, i.e., direct welding and buttering techniques using different filler metals were investigated and characterized via uniaxial creep rupture testing and metallographic examination particularly focusing on the fusion line carbide formation and morphology. For the limited exposure times of 10 kh in this project, the results show that aligned and coarse type I carbide formation is occurring at the 9Cr fusion line between A617 type weld metal. The selection of P87 or A82 type filler metals demonstrated isolated to partly aligned carbides, respectively, at the fusion line. To mitigate the risk to corrosion and achieve a marginal increase in creep performance, buttering techniques are recommended.

Doel 3 and Tihange 2 Reactor Pressure Vessels Indications : Assessment of Nature and Potential Evolution

De Vroey, Séverine, Auteur; De Bruycker, Evy, Auteur; Stubbe, Jacqueline, Auteur; Laborelec

Published in European Nuclear Conference 2016 (ENC 2016) (09/10/2016) / 978-92-950642-7-0

Résumé : This paper presents the Root Cause Analysis (RCA) performed by Laborelec (ENGIE Lab) to identify the nature and the propagation risk of the H-related indications discovered in 2012 in two Belgian reactor pressure vessels. As unexpected results were obtained during irradiation tests on a similar shell material containing flakes (VB395), the study also included the investigation on the cause and the transferability of those results to the Doel 3 and Tihange 2 shells.

The only plausible mechanism at the origin of the indications is hydrogen flaking occurred during the fabrication process.

The study on propagation risk showed that the H level in the material during operation is too low to have a significant impact on the material behaviour and that only low cycle fatigue could potentially propagate the flaws. This mechanism was considered in the assessment that demonstrated the structural integrity of both RPVs.

The atypical embrittlement of VB395 is not due to a hydrogen-related mechanism nor the presence of hydrogen flakes. Two possible mechanisms have been suggested, that might be linked to specificities in the manufacturing history of the VB395 shell (different from the Doel3 and Tihange2 RPV forgings). Therefore, the Doel 3 and Tihange 2 shells should not show the unexpected behaviour under irradiation observed on VB395.

Energiebesparing in industriële gebouwen [Livre] 

Schrauwen, A.P.W.M., Gestionnaire de projet; Bosch, Ralf, Consultant de projet; Neven, Thomas, Consultant de projet; Laborelec. - ISSO - Kennisinstituut voor de installatiesector, 01/06/2016. - (ISSO Handboek; HBebi) .

ISBN 978-90-504-4290-9.

Note de contenu : "Hoe kan de industrie haar energiegebruik verminderen? Ondersteuning biedt dit handboek. De publicatie richt zich op facilitair managers, adviseurs en ontwerpende installateurs. De Nederlandse industrie gebruikt meer dan 40% energie. Dit moet in 2020 voor minstens 14% duurzaam worden opgewekt. Daarbij moet er een energiebesparing zijn doorgevoerd van 9 petajoule. Hoe pakt de industrie dat aan? In dit handboek staan concrete, effectieve en efficiënte van energiebesparende maatregelen per installatiediscipline in een industriële omgeving. Ze zijn vooral van toepassing op bestaande bouw. Enkele onderwerpen zijn ook goed bruikbaar voor nieuwbouw. Het doel van deze publicatie is om facilitair managers en managers technische dienst bewust te maken van het energiegebruik van gebouwgebonden installaties. Daarbij wil de publicatie het belang duiden van de koppeling tussen gebouw, gebouwgebonden installaties, (productie)proces en productiesystemen. Het boek behandelt een breed scala aan onderwerpen: van verwarming, verlichting en elektriciteit tot stoom en perslucht. Behalve de techniek krijgt ook het financiële aspect aandacht; investeringen die zichzelf op termijn terugverdienen bijvoorbeeld. Uiteraard moet in energiebeschouwingen productieprocessen worden meegenomen. Voor deze publicatie gaat dit te ver vanwege de enorme diversiteit aan productieprocessen in de industrie. Hiervoor adviseert het boek de Trias Energetica te volgen." [ISSO]

Fouling propensity of high-phosphorus solid fuels : Predictive criteria and ash deposits characterisation of sunflower hulls with P/Ca-additives in a drop tube furnace

De Fusco, L., Auteur; Boucquey, A., Auteur; Blondeau, Julien, Auteur; Jeanmart, H., Auteur; Contino, Francesco, Auteur; Laborelec

Published in : Fuel, Volume 170, 15 April 2016, Pages 16–26
doi:10.1016/j.fuel.2015.12.017.

Résumé : Fouling from the processing of residual biomass fuels in combustion applications is a major concern. This paper discusses the fouling behaviour of sunflower hulls with a high phosphorus (P) content by means of a broad fuel characterisation strategy including advanced predictive indices, the fuel selective leaching, multiple deposition tests in a Drop Tube Furnace (DTF) and deposits analysis with scanning electron microscopy–energy dispersive X-rays spectroscopy (SEM–EDS). First, we summarise the P-role in the ash chemistry, with a focus on the fouling mechanisms. Second, a characterisation strategy of the ash, based on three indices, including some details from the fuel selective leaching, is proposed to describe the P-rich fuels propensity to foul. The developed approach could be used as a complement to chemical equilibrium models. Thirdly, the characterisation strategy is applied to sunflower hulls. Deposition tests in an industrial scale DTF are performed for the raw fuel, and for the fuel with phosphoric acid (H3PO4) water solution and calcium carbonate (CaCO3) as additives, to obtain different P/K and P/Ca ratios in the fuel composition. The results show that increasing the fuel P-content allows to capture the alkali metals in alkali–alkaline earths–phosphates and alkali–phosphates phases, reducing the occurrence of deposits of S- and Cl-compounds. Low melting temperature phases can be reduced enhancing the formation of coarser, high melting temperatures ash particles formed by K/Na–Ca/Mg–phosphates, by means of an optimised addition of phosphorus- and active calcium-based additives. The experimental results confirmed the added value of the high-P fuels predictive characterisation strategy.

The hexagon of water-steam cycle conservation parameters

Ertryckx, Roger, Auteur; Laborelec

Published in VGB PowerTech Vol. 96 - N. 3 [25/03/2016]. - 71-73

Résumé: "ENGIE Lab Laborelec drafted a concise blueprint of chemistry guidelines applicable to boiler conservation. These conservation guidelines frame six parameters, i.e. the hexagon of parameters, similar to the approach of the actual international guideline philosophy with alarm levels (AL) and target levels (TL). Additionally, the main goal of the conservation programme is to minimise corrosion rate, no longer to the lowest possible level but as low as reasonably achievable." [VGB]

L'hydrogène au long cours

Mertens, Jan, Auteur; Hillegeer, Caroline, Auteur; Lepaumier, Hélène, Auteur; Makhloufi, Camel, Auteur; Baraton, Laurent, Auteur; Moretti, Isabelle, Auteur; Laborelec

Published in Pour la Science CS2018 (Mars 2018). - 22-23

Note de contenu: Comment transporter les énergies renouvelables ? En les convertissant en hydrogène vert, un composé que l’on peut ensuite embarquer, par exemple, dans des bateaux. Sous quelle forme convertir cet hydrogène ?

Influence of heat treatments and build orientation on the creep strength of additive manufactured IN718

Hautfenne, C, Auteur; Nardone, Steve, Auteur; De Bruycker, Evy, Auteur; Laborelec

Published in 4th International ECCC Creep & Fracture Conference (10/09/2017)

Résumé : Metal 3D Printing, also known as Additive Manufacturing, is currently reaching its maturity in high-end industrial applications. A growing consolidation of the Additive Manufacturing industry has been observed the last years in the industrial sector, especially for aerospace, aviation and more recently in the energy sector. When additive manufactured metals are to be used in power generation equipment, it is important to assure their mechanical robustness including sufficient creep strength. Selective laser melting (SLM) technology, based on local fusion of a powder bed, is currently one of the main additive manufacturing techniques for metallic parts. Few publications provide comprehensive results on creep behaviour of nickel-based superalloys produced by SLM. Several IN718 samples were produced by SLM and subjected to different heat treatments. Afterwards short term creep tests (up to 2500h) were carried out on vertically and horizontally built SLM samples. The results were compared with master curves for conventionally produced IN718 material. It was demonstrated that by using the appropriate heat treatment, the short term creep properties of additive manufactured IN718 material can reach the master curve of conventionally produced IN718.

Influence of γ-irradiation and temperature on the mechanical properties of EPDM cable insulation

Sarac, T., Auteur; Quievy, Nicolas, Auteur; Gusarov, A., Auteur; Konstantinovic, M.J., Auteur; Laborelec

Published in : Radiation Physics and Chemistry, Vol. 125, pp. 151-155
10.1016/j.radphyschem.2016.03.024.

Résumé : The mechanical properties of EPDM polymers, degraded as a result of extensive thermal and radiochemical aging treatment, are studied. The focus is given to dose rate effects in polymer insulation materials extracted from industrial cables in use in Belgian nuclear power plants. All studied mechanical characteristics such as the ultimate tensile stress, the Young's modulus, and the total elongation (or elongation at break) are found to be strongly affected by the irradiation dose. The ultimate tensile stress and Young's modulus are clearly exhibiting the dose rate effect, which originated from oxidation mediated interplay of polymer cross-linking and chain scission processes. The change of crossover between these two processes is found to be gradual, without critical dose rate or temperature values. On the contrary, the total elongation is observed not to be sensitive neither to irradiation temperature nor to the dose rate. Both cross-linking and chain scission seem to affect the total elongation in a similar way by reducing the average polymers chain length. This idea is confirmed by the model which shows that all total elongation data as a function of irradiation time can be reproduced by varying a single parameter, the pre-exponential factor of the irradiation rate constant.
Langues : Anglais (eng)

Maximising value for local flexibility management in low voltage distribution networks

Lynch, Patrick, Auteur; Power, Jamie, Auteur; Hickey, Richard, Auteur; Kelly, Derek, Auteur; Messervey, Thomas, Auteur; Manuel, Juan, Auteur; Oualmakran, Youssef, Auteur; Laborelec

Published in : 2016 IEEE International Smart Cities Conference (ISC2), 12-15 Sept. 2016
10.1109/ISC2.2016.7580830.

Résumé : The integration of information and communication technologies into the energy infrastructures will profoundly change the business model structures of the electricity value chain. As business value will be increasingly attached to the bidirectional flows of electricity, data and revenue where flows are driven by a coupling of stakeholder optimization objectives and free market principles, new business platforms will emerge to harness future potential of the energy value chain. Utilizing the business modelling methodology of value network analysis, value flows are mapped within the context of a multi-sided business platform to understand the value created in a network of interdependent relationship, its networked position and the stakeholder interactions required for value delivery. Focusing on the low voltage area of the smart grid, this paper identifies the business platform, its actors, value proposition, and collaboration opportunities involving local energy communities where a local flexibility aggregator facilitates flexibility management between retailers, DSOs, consumers and prosumers.

Online monitoring of coal particle size and flow distribution in coal-fired power plants : Dynamic effects of a varying mill classifier speed

Blondeau, Julien, Auteur; Kock, R., Auteur; Mertens, Jan, Auteur; Eley, A. J., Auteur; Holub, L., Auteur; Laborelec

Published in : Applied Thermal Engineering, Volume 98, 5 April 2016, Pages 449-454

Résumé : The fineness of the coal powder and the uniformity of the coal flow sent to the burners are crucial parameters to achieve an effective combustion in coal-fired power plants. This study presents a methodology for the online monitoring of the (i) coal particle size distribution and (ii) coal flow distribution between burners at the outlet of a roller mill installed in 660 MWe coal-fired power plant. The effect of a varying centrifugal classifier speed on these two properties was investigated. To the best knowledge of the authors, it is the first time that such an effect is monitored online in a large scale utility boiler. For a classifier speed between 73 and 99 rpm, the mass fraction of particles smaller than 75 μm varied between 66 and 74%. The coal flow distribution between burners was strongly improved when the particle size was the smallest: the maximum deviation from the average flow rate was reduced from 14% at 73 rpm to 9% at 99 rpm.

Overview of aerosols in post-combustion CO2 capture

Khakharia, Purvil, Auteur; Mertens, Jan, Auteur; Abu-Zahra, M.R.M., Auteur; Vlugt, Thijs J.H., Auteur; Goetheer, E.L.V., Auteur; Laborelec

Published in Absorption-Based Post-Combustion Capture of Carbon Dioxide / Feron, Paul H.M. (16/06/2016) / 978-0-08-100514-9

Résumé : "This chapter gives an overview on the issue of aerosol-based emissions observed in post-combustion CO2 capture. Firstly, the evidence of aerosol-based emissions obtained from different pilot plant tests is presented. Unlike vapor-based emissions, which can be quantified and predicted based on the vapor pressure of the component, aerosol-based emissions are difficult to predict as it depends on several parameters. The key elements identified to explain the observation of aerosol-based amine emissions in PCC are discussed here. As the issue is being better understood, several countermeasures have been tested. Their efficiency in reducing aerosol-based emissions and possible disadvantages are summarized. The remaining knowledge gaps both from an understanding point of view as well as from a countermeasures point of view are outlined, and can serve as a basis for future research on this topic." [©Elsevier]

Performance and reliability assessment of NMC lithium ion batteries for stationary application

Nanini-Maury, Elise, Auteur; Van den Bossche, Peter, Auteur; Li, Y., Auteur; Omar, Noshin, Auteur; Van Mierlo, Joeri, Auteur; Laborelec

Published in : Vehicle Power and Propulsion Conference (VPPC), 2016 IEEE 10.1109/VPPC.2016.7791747.

Résumé : One of the main barriers to increasing the market size of lithium ion batteries for stationary applications is their lifetime. In order to select the optimal cells for integrating into grids, battery performance characterization and lifetime analysis need to be carried out to assess the battery performance and reliability under various operating conditions. In this work, a comprehensive investigation has been carried out to address these issues for a lithium nickel manganese cobalt oxide battery type. Moreover, an empirical ageing model for the lifetime prediction is presented.

Prevention of Mist Formation in Amine Based Carbon Capture : Field Testing Using a Wet ElectroStatic Precipitator (WESP) and a Gas-Gas Heater (GGH)

Mertens, Jan, Auteur; Khakharia, Purvil, Auteur; Rogiers, Pieter, Auteur; Blondeau, Julien, Auteur; Lepaumier, Hélène, Auteur; Goetheer, Earl, Auteur; Schallert, Bernd, Auteur; Schaber, Karlheinz, Auteur; Moretti, Isabelle, Auteur; Laborelec

Published in : Energy Procedia, Volume 114, July 2017, Pages 987-999
10.1016/j.egypro.2017.03.1244.

Résumé : This study presents the results of two field tests that aimed at evaluating two countermeasures (WESP and GGH) to avoid acid mist formation. A WESP is shown to be very efficient for the removal of nuclei from the flue gas (100% efficient) and thus can prevent aerosol formation inside an amine based absorber. This is however only valid in the absence of SO2 in the flue gas entering the WESP. A decreasing WESP efficiency is noted in the presence of SO2 with increasing voltages as a result of newly formed aerosols inside the WESP. This implies that no or very low levels of SO2 should be present in the flue gas entering the WESP. Since most of the amine carbon capture installations have a pre-scrubber (usually using NaOH to remove residual SO2 in the flue gas leaving the power plant's Flue Gas Desulphurisation) in front of their amine absorber, the WESP must be installed behind this pre-scrubber and not in front of it. Having a Gas-Gas Heater (or any type of flue gas cooling such as a Low Temperature Heat Exchanger) installed upstream of the wet scrubbing may prevent homogenous nucleation and thus prevent the conversion of H2SO4 into sulfuric acid aerosols and consequently mist formation issues in the amine based carbon capture installation. Which option to choose amongst the two countermeasures presented in this study will depend on whether a new built installation is being considered or whether a carbon capture is planned as a retrofit into an existing installation.

Producing FGD gypsum with low Hg content

Van Dijen, Frans, Auteur; Laborelec

Published in VGB PowerTech Vol. 96 - N. 5 [25/05/2016]. - 74-79

Résumé: Legislation in the EU regarding more stringent emission limits for Hg with flue gases is making progress. When Hg emissions to the air of coal- and lignite-fired power plants are reduced, more Hg ends-up either in the fly ash, in the flue gas desulphurisation (FGD) gypsum and/or in the FGD effluent. The goals are reducing Hg emissions to the air at low/zero costs, which means using the existing equipment for flue gas purification; keeping marketable residues: fly ash, bottom ash and FGD gypsum; and using the existing wastewater treatment plant (WWTP) as Hg sink. These three goals seem feasible.

A quick on-line state of health estimation method for Li-ion battery with incremental capacity curves processed by Gaussian filter

Li, Y., Auteur; Abdel-Monem, Mohamed, Auteur; Gopalakrishnan, Rahul, Auteur; Berecibar, Maitane, Auteur; Nanini-Maury, Elise, Auteur; Laborelec

Published in : Journal of Power Sources, Volume 373 (January 2018), p. 40-53
https://doi.org/10.1016/j.jpowsour.2017.10.092.

Résumé : This paper proposes an advanced state of health (SoH) estimation method for high energy NMC lithium-ion batteries based on the incremental capacity (IC) analysis. IC curves are used due to their ability of detect and quantify battery degradation mechanism. A simple and robust smoothing method is proposed based on Gaussian filter to reduce the noise on IC curves, the signatures associated with battery ageing can therefore be accurately identified. A linear regression relationship is found between the battery capacity with the positions of features of interest (FOIs) on IC curves. Results show that the developed SoH estimation function from one single battery cell is able to evaluate the SoH of other batteries cycled under different cycling depth with less than 2.5% maximum errors, which proves the robustness of the proposed method on SoH estimation. With this technique, partial charging voltage curves can be used for SoH estimation and the testing time can be therefore largely reduced. This method shows great potential to be applied in reality, as it only requires static charging curves and can be easily implemented in battery management system (BMS).

Recycling of used SCR catalysts 

Van Dijen, Frans, Auteur; Leuschner, Thomas, Auteur; Laborelec

Published in VGB PowerTech Vol. 96 - N. 6 [25/06/2016]. - 71-77

Résumé: Used Selective Catalytic Reduction (SCR) catalysts are best regenerated. When used catalysts are deteriorated from a mechanical point of view, catalyst regeneration is not possible, and disposal must be considered. Land filling of used catalysts is discouraged by EU legislation. This paper is about other methods for disposal of used catalysts and mainly focussing on “recycling”. This recycling of used catalysts proved technically feasible and a first financial analysis is presented. There is discussion whether used catalysts is hazardous waste or normal waste.

Residential Electricity Tariffs in Europe : Current Situation, Evolution and Impact on Residential Flexibility Markets

Oualmakran, Youssef, Auteur; Espeche, Juan Manuel Espeche, Auteur; Sisinni, Mario, Auteur; Messervey, Thomas, Auteur; Lennard, Zia, Auteur; Laborelec

Published in : Proceedings of the Sustainable Places 2017 (SP2017) Conference, 2017, 1, 973.
doi:10.3390/proceedings1070973.

Résumé : Residential flexibility (a.k.a demand response) is a key component of smart grids to reduce our carbon footprint, to have reliable power (balance between power and demand, and avoiding congestion) and more affordable electricity tariffs. However, to have a significant participation in the flexibility markets, households needs good price signals. Today, the electricity bill components (volumetric and capacity for both consumption and generation) are evolving and grid services are increasingly more available to households. This is due to the evolution in the energy mix, deployment of new technologies (smart meter roll-out, gradual uptake of electric vehicles, heat pumps and batteries), regional integration (interconnectors and integration of balancing markets) and evolution of society (sharing economy or Peer2peer and ubiquity of smartphones). These trends will have a quantitative impact on the different energy bills in the short term (2020) and longer term. Further investigation is also suggested to go from the qualitative analysis to a better quantitative analysis.

Results from aerosol measurement in amine plant treating gas turbine and Residue Fluidized Catalytic Cracker flue gases at the CO2 Technology Centre Mongstad

Lombardo, Gerard, Auteur; Fostas, Berit F., Auteur; Shah, Muhammad Ismail, Auteur; Morken, Anne Kolstad, Auteur; Hvidsten, Odd Arne, Auteur; Mertens, Jan, Auteur; Hamborg, Espen Steinseth, Auteur; Laborelec

Published in : In Energy Procedia 114 (2017), p. 1210-1230
doi: 10.1016/j.egypro.2017.03.1377.

Résumé : This work discusses the relation between flue gas particle content, mainly related to sulfuric acid aerosols and dust, and corresponding MEA emissions. The work lays grounds for future necessary pre-treatment options for various flue gases with high aerosol content in order to operate post-combustion amine plants with minimum emissions. In 2015, the CO2 Technology Center Mongstad (TCM DA), operated a test campaign using aqueous monoethanolamine (MEA) solvent at 30 wt%. The main objective was to demonstrate and document the performance of the TCM DA Amine Plant located in Mongstad, Norway. Two weeks were dedicated to the aerosol measurement testing.

Root Cause Analysis and Characterisation of the Doel 3 and Tihange 2 Reactor Pressure Vessel Flaws

De Vroey, Séverine, Auteur; De Bruycker, Evy, Auteur; De Smet, Michel, Auteur; Stubbe, Jacqueline, Auteur; Laborelec. - American Society of Mechanical Engineers International (ASME International), 17/07/2016.

Published in  ASME 2016 Pressure Vessels and Piping Conference (PVP2016) (17/07/2016). PVP2016-63883

Résumé : This paper presents the root cause analysis and characterisation of the indications discovered in two Belgian pressurized water reactor (PWR) pressure vessels (Doel 3 and Tihange 2), during in service inspections performed in 2012.
The only plausible mechanism at the origin of the detected indications is hydrogen flaking during fabrication. Flaking could occur because of the local combination of high hydrogen concentration, stresses and susceptible microstructure.
The phenomenology study performed on several materials including flaked materials provided precious information for the Safety Case: it confirmed the cause of the indications and evidenced that flaking exclusively occurs in segregated zones and that the ligament between flakes is sound.
The paper also briefly addresses the possibility of evolution of the indications during operation: low cycle fatigue during transients is identified as the only mechanism likely to induce flaw growth in operation. A particular attention has been paid to the potential hydrogen effects.

Root Cause Analysis of the Unexpected Behaviour of a Flaked Material Under Irradiation and Transferability to the Doel 3/Tihange 2 Reactor Pressure Vessels

De Bruycker, Evy, Auteur; De Vroey, Séverine, Auteur; Hallet, Xavier, Auteur; Stubbe, Jacqueline, Auteur; Nardone, Steve, Auteur; Laborelec

Published in ASME 2016 Pressure Vessels and Piping Conference (PVP2016) (17/07/2016). PVP2016-63882.

Résumé : During the 2012 outage at Doel 3 (D3) and Tihange 2 (T2) Nuclear Power Plants (NPP), a large number of nearly-laminar indications were detected mainly in the lower and upper core shells. The D3/T2 shells are made from solid casts that were pierced and forged.
Restart authorization in 2013 was accompanied by a number of “mid-term” requirements, to be completed during the first operating cycle after the restart. One of these requirements was the mechanical testing of irradiated specimens containing hydrogen flakes. These tests showed unexpected results regarding the shift in the Reference Temperature for Nil Ductility Transition (RTNDT) of the flaked material VB395 (Steam Generator shell rejected because of flakes) after irradiation.
This paper presents the root cause analysis of this unexpected behaviour and its transferability (or not) to the D3/T2 Reactor Pressure Vessels (RPVs).
A mechanistic and a manufacturing based approach were used, aiming at identifying the microstructural mechanisms responsible for the atypical embrittlement of VB395 and evaluating the plausibility of these mechanisms in the D3/T2 RPVs.
This work was based on expert’s opinions, literature data and test results. Both flaked and unflaked samples have been investigated in irradiated and non-irradiated condition.
All hydrogen-related mechanisms were excluded as root cause of the unexpected behaviour of VB395. Two possible mechanisms at the basis of the atypical embrittlement of VB395 were identified, but are still open to discussion. These mechanisms could be linked to the specific manufacturing history of the rejected VB395 shell.
Since the larger than predicted shift in transition temperature after irradiation of VB395 is not linked with the hydrogen flaking and since none of the specific manufacturing history features that are possible root causes are reported for the D3/T2 RPVs, the D3/T2 shells should not show the unexpected behaviour observed in VB395.

Stray Gassing of Transformer Insulating Oils : Impact of Materials, Oxygen Content, Additives, Incubation Time and Temperature, and Its Relationship to Oxidation Stability

Eeckhoudt, Steve, Auteur; Autru, Stijn, Auteur; Lerat, Luc, Auteur; Laborelec

Published in IEEE Electrical Insulation Magazine Vol. 33 - N. 6 (November/December 2017). - 27-32

Résumé: For many years, dissolved gas analysis (DGA) has been considered worldwide as the most important technique for evaluating the state of health of oil-filled power transformers. Based on regular analysis and trending of the dissolved gases extracted from insulating oil samples, an assessment can be made whether internal transformer abnormalities are present and how critical these abnormalities are [1], [2]. The article examines the impact of temperature, oxygen, antioxidant, and incubation time on stray gassing of unused and in-service mineral oils and the relationship of gassing to oxidation stability.

Sulphuric acid measurements at ppb levels at a natural gas-fired CCGT

Koczab, Christine, Auteur; Van Dijen, Frans, Auteur; Chothani, Chetan, Auteur; Lauwers, Mark, Auteur; Laborelec

Published in VGB PowerTech Vol. 96 - N. 3 [25/03/2016]. - 78-80

Résumé: "The Heat Recovery Steam Generators (HRSGs) operated as part of Combined Cycle Gas Turbine (CCGT) power stations experience Sulphuric Acid corrosion due to the Sulphur in the fuel. This in turn, causes emissions and immissions of acid particles. Under this project, flue gas measurements of SO2, SO3/H2SO4 and Acid Dew Point (ADP) were performed at a HRSG at such a site. This project demonstrated that measurement of SO2 and SO3 at ppb levels in “clean” flue gases seems possible, and further it seems also possible to measure the ADP of “clean” flue gases to levels below 80°C." [VGB]    

Ten years of experience with 3 kHz water tree test

Burceanu, Monica, Auteur; De Clerck, Quentin, Auteur; Tits, Yvan, Auteur; Laborelec

Published in : 24th International Conference & Exhibition on Electricity Distribution (CIRED), 12-15 June 2017, p. 468-471
doi: 10.1049/oap-cired.2017.0598.

Résumé : Electrical trees and degradations due to water trees (WTs) are one of the major causes of premature ageing and failure of extruded medium voltage cables. The estimation of WTs resistance and lifetime of cable insulations represents all over the world an important issue for cable owners. The reproduction of WTs in a laboratory in a reasonable duration is highly helpful not only to provide advices for specifications and purchasers but also to plan the maintenance programs. A lot of accelerated tests have already been developed on flat samples with defects created by abrasive study or on a bulk sample using needles. Compared to these methods, the 3 kHz method is highly appreciated. Since its development in 2006, more than 200 cable samples have been tested by Laborelec according to the 3 kHz method. This study describes some of the most interesting results obtained during the last 10 years with this method.

The study of temperature and radiation induced degradation of cable polymers : A comparison between the mechanical properties of industrial and neat EPDM

Sarac, T., Auteur; Quievy, Nicolas, Auteur; Gusarov, A., Auteur; Konstantinovic, M.J., Auteur; Laborelec

Published in : Procedia Structural Integrity, Volume 2, 2016, Pages 2405–2414 (21st European Conference on Fracture, ECF21, 20-24 June 2016, Catania, Italy)
doi:10.1016/j.prostr.2016.06.301.

Résumé : The mechanical properties of industrial and neat Ethylene Propylene Diene Monomer (EPDM) polymers, aged under γ-irradiation at different temperatures, are studied. The focus is given to the dose rate effects in polymer insulation materials, so the ageing is performed in the wide range of dose rates, doses and temperatures. Industrial EPDM samples are extracted from the cables in use in Belgian Nuclear Power Plants (NPP), and the neat EPDM samples are produced in the laboratory. The mechanical tests of non-aged and aged polymers are performed, and the methodology of estimating the polymer life time is discussed. The ultimate tensile stress and elongation at break are found to be strongly affected by both irradiation condition and temperature. The ultimate tensile stress clearly exhibits the dose rate effect observed through the shift of the crossover between cross-linking to chain scission process as a function of the dose. This crossover shifts to high dose for large dose rates, while the opposite is observed by increasing the temperature. Dose rate effect is less evident in the elongation at break data, probably because both cross-linking and chain scission affect the elongation at break in the same way, by decreasing it. In comparison to industrial EPDM aged under the same conditions, the cross-linking to chain scission crossover appears at lower dose in neat polymer and the elongation at break decreases faster by increasing the dose. In addition, the elongation at break experimental results can be modeled by changing single parameter, namely pre-exponential factor of the irradiation rate constant. This confirms that both aging processes, cross-linking and chain scission affect the elongation at break in a similar way, by deteriorating network structure responsible for polymer elastic properties. Irradiation rate constant is found to follow the square root dependence for industrial EPDM, while the linear dependence is observed for the neat EPDM. This indicates the existence of different degradation processes in these two polymers.

Ultrasonic Inspection of Hydrogen Flakes in Large Forgings : From Qualification to Site Inspection

Moussebois, Dominique, Auteur; Ancrenaz, Patrick, Auteur; Laborelec

Published in ASME 2016 Pressure Vessels and Piping Conference (PVP2016) (17/07/2016). PVP2016-63860.

Résumé : During 2012 RPVs inspections, nearly-laminar indications were detected in the lower and upper core shells of Doel 3 and Tihange 2 RPVs. As a consequence, the Doel 3 and Tihange 2 NPPs have to stay in cold shutdown until it was proved that they can be safely operated. The performance and capability of the applied UT technique to detect and characterize hydrogen flakes had to be confirmed. To achieve this objective, extensive investigations were launched on blocks extracted from a steam generator shell known for containing hydrogen flakes.
The paper describes the UT validation performed and the results of the destructive tests which enable to demonstrate the capability of a straight ultrasonic beam to detect and size nearly laminar indications and to correctly identify ligaments between two adjacent indications. It addresses the formal extension of qualification performed by correlating UT measurements acquired on a large numbers of real hydrogen flakes, simulations of UT responses and destructive examinations.
Lessons learned from the experiments are finally described.

Understanding and Modelling the Effect of Dissolved Metals on Solvent Degradation in Post Combustion CO2 Capture Based on Pilot Plant Experience

Dhingra, Sanjana, Auteur; Khakharia, Purvil, Auteur; Rieder, Alexander, Auteur; Cousins, Ashleigh, Auteur; Reynolds, Alicia, Auteur; Knudsen, Jacob, Auteur; Andersen, Jimmy, Auteur; Irons, Robin, Auteur; Mertens, Jan, Auteur; Abu Zahra, Mohammad, Auteur; Van Os, Peter, Auteur; Goetheer, Earl, Auteur; Laborelec

Published in : Energies, Vol. 10, n°5, MDPI, 2017.
doi:10.3390/en10050629.

Résumé : Oxidative degradation is a serious concern for upscaling of amine-based carbon capture technology. Different kinetic models have been proposed based on laboratory experiments, however the kinetic parameters included are limited to those relevant for a lab-scale system and not a capture plant. Besides, most of the models fail to recognize the catalytic effect of metals. The objective of this work is to develop a representative kinetic model based on an apparent auto-catalytic reaction mechanism between solvent degradation, corrosion and ammonia emissions. Measurements from four different pilot plants: (i) EnBW’s plant at Heilbronn, Germany (ii) TNO’s plant at Maasvlakte, The Netherlands; (iii) CSIRO’s plants at Loy Yang and Tarong, Australia and (iv) DONG Energy’s plant at Esbjerg, Denmark are utilized to propose a degradation kinetic model for 30 wt % ethanolamine (MEA) as the capture solvent. The kinetic parameters of the model were regressed based on the pilot plant campaign at EnBW. The kinetic model was validated by comparing it with the measurements at the remaining pilot campaigns. The model predicted the trends of ammonia emissions and metal concentration within the same order of magnitude. This study provides a methodology to establish a quantitative approach for predicting the onset of unacceptable degradation levels which can be further used to devise counter-measure strategies such as reclaiming and metal removal.

Is Vehicle-to-Home or Vehicle-to-Grid Suitable for the EV User? : A Discussion from a One Year Intensive Monitoring

De Vroey, Laurent, Auteur; Laborelec

Published in : EVS29 Electric Vehicle Symposium & Exhibition 2016 (Session 6C: Putting V2X to Work)

Weldability assessment and high-temperature properties of advanced creep resisting austenitic steel X6CrNiNbN25-20 (DMV310N/HR3C)

Vekeman, Johan , Auteur; Huysmans, Staf, Auteur; Hautfenne, C, Auteur; Laborelec

Published in Welding in the World Vol. 60 - N. 5 (September 2016). - 1009-1019

Résumé: The modern Ultra Super Critical Power Plants (USC PP) applying the 600 °C technology require advanced stainless steels in superheater/reheater systems in order to cope with the increased steam parameters. Different grades of stainless steels have been developed by increasing Cr-contents, alloying with stabilizing and precipitating elements as well as thermomechanical heat treatments resulting in high creep rupture strengths and improved oxidation/corrosion resistance. In the context of a collaborative research project, X6CrNiNbN25-20 (DMV310N/HR3C) has been investigated. The main focus of the research project was on characterization and weldability assessment. As a result, the base metal under investigation was compared with governing code cases and specifications. Base metal chemical composition, microstructures, mechanical properties, reheat cracking sensitivity, and hot ductility as well as creep rupture strengths have been investigated. A weldability assessment, including thermal simulation and welding procedure qualifications, has been performed to establish parameter windows for similar and dissimilar welding. Dissimilar welding between grade 92 and austenitic steel tubes has been performed. The project also took the opportunity to investigate the behavior of a recently developed gas tungsten arc welding (GTAW) P87 consumable for dissimilar welding. Cross-weld creep rupture tests have been conducted for both similar and dissimilar welding, while aging tests addressed microstructural stability.

Welds in modern Grade 91/92 creep resisting steels : Common and more specific pitfalls

Huysmans, Staf, Auteur; Vanderlinden, Frédéric, Auteur; Lot, Michiel, Auteur; Laborelec

Published in : 42nd MPA-Seminar - October 4th and 5th, 2016

Résumé : The numerous forced shutdowns and unexpected damages experienced in Power Industry show that new generation materials, exposed to USC operating conditions, are not fully understood yet. Modern creep resisting steels are developed for service at high temperatures and severe operating conditions. Although weldability has been improved over the years, narrow operating windows for welding, bending, heat treatments and operational exposure persist for these materials. Non-respect of these limiting parameters ends up in premature damages or catastrophic failures. Therefore, awareness and full understanding of strengthening and failure mechanisms as well as welding metallurgy and microstructural stability are required to guarantee safe operation. As a consequence, there is a need for intensifying quality control during fabrication. On the other hand, training focusing on specific creep resisting materials fabrication issues becomes a must. In this paper a few common and more specific pitfalls are discussed and possible remedies outlined.

Technical publications 2015

An automated residential demand response pilot experiment, based on day-ahead dynamic pricing

Vanthournout, Koen, Auteur; Dupont, Benjamin, Auteur; Foubert, Wim, Auteur; Stuckens, Catherine, Auteur; Claessens, Sven, Auteur; Laborelec

in Applied Energy N. 155 (1 October 2015). - 195-203

Dynamic pricing is a popular method to realize demand response. Automated response from smart appliances reduces the comfort impact for the users and hence reduces response fatigue concerns, while improving the price response. However, real-life experience with smart appliances is typically limited to heating and cooling appliances. The Linear pilot was a residential demand response pilot with 240 Belgian families using smart dishwashers, washing machines, tumble dryers and domestic hot water buffers in various experiments. Goal was to evaluate the performance of those smart appliances in real life circumstances for various applications of demand response. The results for the day-ahead dynamic pricing experiments, conducted from September 2013 till July 2014 at 58 families, are presented. These demonstrate a significant shift of the flexible share of the electricity consumption to the lower price periods. The dishwashers outperform the other appliances. The domestic hot water buffer shows the lowest performance in terms of relative cost savings, but its much larger energy consumption translates to larger absolute savings. As the flexible share of the total consumption remains small, the non-smart share represents a financial risk for the consumer. The smart appliances were well received by the users and no response fatigue was observed. However, there was a high variation in the group of pilot participants, both in terms of energy consumption as in terms of flexibility offered.

CFD modelling of CFBC as a valuable tool for the solid fuels-fired power plants of the future

Van Dijen, Frans, Auteur; Omer, Adlan, Auteur; Laborelec

in VGB PowerTech Vol. 95 - N. 10 [25/10/2015]. - 68-72

Computational Fluid Dynamics (CFD) modelling is an important tool for the manufacturers of Circulating Fluidised Bed Combustion (CFBC) systems. The application of CFD and critical analysis of the results require much knowledge. This is illustrated by modelling the Polaniec unit, assuming different fuels, loads and injections of secondary air. In the first parts of the paper attention is paid to the importance of CFBC for the future and to fuel flexibility, which is also of growing importance. The results of the CFD modelling highlight the importance of homogeneous and symmetrical design of the CFBC. Also fuel flexibility should be considered with the design of the CFBC." [VGB]

CFD simulations of Heavy Fuel Oil or Biodiesel in a steam generator for city heating

Tap, F.A., Auteur; Tyagi, R., Auteur; Rochaya, David, Auteur; Blondeau, Julien, Auteur; Laborelec. - Cenertec, 07/04/2015.

As part of a study of the conversion of Heavy Fuel Oil (HFO) boilers to biodiesel, combustion simulations were conducted to evaluate the impact of fuel switching on the boiler operation, with particular attention to the evaluation of the heat fluxes and potential risks of DNB (Departure from Nucleate Boiling).

Two numerical analyses were performed on two nearly identical boiler systems, one fired with Heavy Fuel Oil and one fired with biodiesel. The 8 burners are arranged in two rows of 4 burners each, all with a swirling air flow in the same direction. Specific chemical kinetics for HFO and biodiesel were used and the geometry of the burners was accurately represented. Clear differences between the two types of flames are observed from the simulations, but the differences in the profiles of temperature and heat fluxes are moderate.

The main conclusions for the differences in the simulated flame topologies are:

Concerning the heat fluxes, the absolute peak flux obtained with biodiesel fuel is about 496 kW / m², against 656 kW / m² for HFO. Conservative calculations indicate that the mass as steam will not reach the critical steam as responsible for DNB. The flue gas temperatures at the inlet of superheater are substantially lower with biodiesel as compared to HFO. This has as consequence that the radiative heat transfer in the superheater section is less in the biodiesel case.

Published in : INFUB - 10th 2015 European Conference on Industrial Furnaces and Boilers

Collection and Generation of Sulfuric Acid Aerosols in a Wet Electrostatic Precipitator

Anderlohr, Christopher, Auteur; Brachert, Leonie, Auteur; Mertens, Jan, Auteur; Schaber, Karlheinz, Auteur; Laborelec. - Taylor & Francis, 21/01/2015.

Résumé : Wet electrostatic precipitators (WESPs) are considered to be a possible technology for the control of sulfuric acid mist. The performance of a lab-scale WESP was investigated as a precipitator for sulfuric acid aerosol droplets produced under controlled conditions in a pilot plant. It was found that for higher levels of residual SO2 in the flue gas, WESP collection efficiencies were greatly reduced due to aerosol formation inside the WESP. Investigations showed a strong correlation of aerosol emission from the WESP with incoming SO2 concentration and operating voltage. It is suspected that the reactive species produced in the nonthermal plasma of the corona discharge oxidize the SO2 to SO3 which forms sulfuric acid. This causes supersaturation with subsequent homogeneous nucleation and thus aerosol formation.

Published in : Aerosol Science and Technology, 49:3, 144-151

Counter-Measures for Aerosol-Based Emission [Article]

Khakharia, Purvil, Auteur; Mertens, Jan, Auteur; Brachert, Leonie, Auteur; Huizinga, Arjen, Auteur; Anderlohr, Christopher, Auteur; Schallert, Bernd, Auteur; Schaber, Karlheinz, Auteur; Goetheer, Earl, Auteur; Laborelec. - Ex Ordo, 16/06/2015.

Résumé : Aerosol based emissions in Post Combustion CO2 Capture have become a point of concern in the past few years. Several lab and pilot scale studies have focused on the quantifying these emissions, understanding the cause and subsequently proposing relevant mechanisms 1–3. Particularly, the particle number concentration is an important parameter in determining the extent of aerosol based emissions. Other factors such as particle size distribution, supersaturation, and reactivity of the amine also play an important role. Along with quantifying and understanding aerosol-based emissions, it is of greater importance to identify suitable counter-measures against it. It is known that aerosol-based emission of amine can be in the order of a gram per normal cubic meter and cannot be reduced by conventional emission countermeasures such as a general demister and a pump-around water wash. In this study, different counter-measures were tested for their ability to reduce aerosol based-emission originating from H2SO4 nuclei in the flue gas in CO2 capture mini-plant as shown in Figure 1.

Published in : The 8th Trondheim CCS Conference

Economic Analysis of a Micro Humid Air Turbine for Domestic Applications [Article]

/ Montero Carrero, Marina, Auteur; De Paepe, Ward, Auteur; Parente, Alessandro, Auteur; Blondeau, Julien, Auteur; Laget, Hannes, Auteur; Contino, Francesco, Auteur; Laborelec. - Elsevier, 12/01/2015.

Résumé : Micro Gas Turbines (mGT) appear as a promising technology for small-scale (up to 500 kW) Combined Heat and Power (CHP) production. However, their rather low electric efficiency limits their profitability when the heat demand decreases. Hot liquid water injection in mGTs –particularly within the micro Humid Air Turbine (mHAT) cycle– allows increasing electric efficiency by making use of the flue gas residual heat in moments of low heat demand.

Based on simulations performed on a Turbec T100 mGT –modified to operate as an mHAT– installed at the VUB, this paper presents an analysis of the economic profitability of such facility running on real network conditions. The study is performed assuming typical electricity and heat demand profiles for a domestic consumer. 25 natural gas and electricity price combinations have been taken into consideration, along with two types of domestic customers –with higher and lower heat demands. Results show that the profitability of the mHAT with respect to the equivalent CHP facility increases with higher electricity and lower natural gas prices. In particular, given a certain number of CHP running hours and a natural gas price, there is a threshold for the electricity price above which the net income of the mHAT unit is always higher than that of the corresponding CHP unit. In addition, water-cleaning costs for the mHAT case appear to constitute only 1 to 2.5% of total running costs.

Published in : Energy Procedia, Volume 61, 2014, Pages 1476-1482, ISSN 1876-6102

Environmental performance of electricity storage systems for grid applications, a life cycle approach

/ Oliveira, Luis, Auteur; Messagie, Maarten, Auteur; Mertens, Jan, Auteur; Laget, Hannes, Auteur; Coosemans, Thierry, Auteur; Van Mierlo, Joeri, Auteur; Laborelec

in Energy Conversion and Management Vol. 101 (1 September 2015). - 326–335

Résumé: In this paper, the environmental performance of electricity storage technologies for grid applications is assessed. Using a life cycle assessment methodology we analyze the impacts of the construction, disposal/end of life, and usage of each of the systems. Pumped hydro and compressed air storage are studied as mechanical storage, and advanced lead acid, sodium sulfur, lithium-ion and nickel–sodium-chloride batteries are addressed as electrochemical storage systems. Hydrogen production from electrolysis and subsequent usage in a proton exchange membrane fuel cell are also analyzed. The selected electricity storage systems mimic real world installations in terms of capacity, power rating, life time, technology and application. The functional unit is one kW h of energy delivered back to the grid, from the storage system. The environmental impacts assessed are climate change, human toxicity, particulate matter formation, and fossil resource depletion. Different electricity mixes are used in order to exemplify scenarios where the selected technologies meet specific applications. Results indicate that the performance of the storage systems is tied to the electricity feedstocks used during use stage. Renewable energy sources have lower impacts throughout the use stage of the storage technologies. Using the Belgium electricity mix of 2011 as benchmark, the sodium sulfur battery is shown to be the best performer for all the impacts analyzed. Pumped hydro storage follows in second place. Regarding infrastructure and end of life, results indicate that battery systems have higher impacts than mechanical ones because of lower number of cycles and life time energy.

Field experience with advanced condition monitoring of wind turbines

/ le Fevere de ten Hove, Olivier, Auteur; Laborelec

in VGB PowerTech Vol. 95 - N. 7 [25/07/2015]. - p. 57-63

Résumé: Condition monitoring for wind turbines must combine early warning of deviating operating behaviour, reliable fault detection, accurate fault diagnosis and the ability to handle versatile data inputs, and all this at an economically acceptable cost. Pattern recognition and intelligent data mining are a way forward to transfer the large amount of data that is continuously generated by a wind farm into actionable information, assisting the wind farm operator in the optimisation of the operation and maintenance process and in the assessment of the impact of events and actions on the remaining lifetime of the assets.

Fouling propensity of high-phosphorus solid fuels : Predictive criteria and ash deposits characterisation of sunflower hulls with P/Ca-additives in a drop tube furnace [Article]

/ De Fusco, L., Auteur; Boucquey, A., Auteur; Blondeau, Julien, Auteur; Jeanmart, H., Auteur; Contino, Francesco, Auteur; Laborelec. -

Elsevier, 22/12/2015. doi:10.1016/j.fuel.2015.12.017.

Résumé : Fouling from the processing of residual biomass fuels in combustion applications is a major concern. This paper discusses the fouling behaviour of sunflower hulls with a high phosphorus (P) content by means of a broad fuel characterisation strategy including advanced predictive indices, the fuel selective leaching, multiple deposition tests in a Drop Tube Furnace (DTF) and deposits analysis with scanning electron microscopy–energy dispersive X-rays spectroscopy (SEM–EDS). First, we summarise the P-role in the ash chemistry, with a focus on the fouling mechanisms. Second, a characterisation strategy of the ash, based on three indices, including some details from the fuel selective leaching, is proposed to describe the P-rich fuels propensity to foul. The developed approach could be used as a complement to chemical equilibrium models. Thirdly, the characterisation strategy is applied to sunflower hulls. Deposition tests in an industrial scale DTF are performed for the raw fuel, and for the fuel with phosphoric acid (H3PO4) water solution and calcium carbonate (CaCO3) as additives, to obtain different P/K and P/Ca ratios in the fuel composition. The results show that increasing the fuel P-content allows to capture the alkali metals in alkali–alkaline earths–phosphates and alkali–phosphates phases, reducing the occurrence of deposits of S- and Cl-compounds. Low melting temperature phases can be reduced enhancing the formation of coarser, high melting temperatures ash particles formed by K/Na–Ca/Mg–phosphates, by means of an optimised addition of phosphorus- and active calcium-based additives. The experimental results confirmed the added value of the high-P fuels predictive characterisation strategy.

Published in : Fuel, Volume 170, 15 April 2016, Pages 16–26

Impact of smart charging on the EV battery ageing - Discussion from a 3 years real life experience [Article]

/ De Vroey, Laurent, Auteur; Jahn, Rafael, Auteur; Omar, Noshin, Auteur; Van Mierlo, Joeri, Auteur; Laborelec. - 03/05/2015. - 8 p.

Résumé : Smart charging is related to a possible adjustment of the charging sequences with some energetic constraints. It can be defined in different ways, namely depending on the specific objectives. However, they all result in similar consequences for the charging sequences, with regard to conventional charging: potential delay, interruption(s) and power modulation of the charging cycles.

It is commonly admitted that smart charging will be necessary to face the growing deployment of EVs, namely for the local grid operators. Moreover, from the user point of view, smart charging can be seen as an additional motivation for the choice of an EV instead of a conventional car, if e.g. lower electricity tariffs are proposed for charging flexibility. In this paper, a quantitative evaluation is performed of EV battery ageing, in function of the charging conditions, with a special focus on the smart charging specificities. The study is based on real data from a three years continuous monitoring of five Peugeot iOn cars, a first of a kind campaign that was performed in Belgium in the Brussels area during the period 2011-2014. Different use profiles and charging patterns were observed. Among other elements, battery capacity and battery efficiency and their evolution in time were calculated, taking into account various factors, such as the seasonal impacts. It will first be highlighted that, whatever their charging patterns, all the considered cars are showing a significant flexibility potential, making them good candidates for smart charging. The impact of smart charging on battery ageing will then be discussed, with a focus on the charging frequency, the average state of charge and the impact of faster versus slower charge on battery capacity. This long time monitoring period allows to clearly identify the time evolution trends, leading to unique conclusions from the real life.

Published in : EVS28 International Electric Vehicle Symposium and Exhibition (2015)

Impacts of electricity mix, charging profile, and driving behavior on the emissions performance of battery electric vehicles : A Belgian case study

/ Rangaraju, Surendraprabu, Auteur; De Vroey, Laurent, Auteur; Messagie, Maarten, Auteur; Mertens, Jan, Auteur; Van Mierlo, Joeri, Auteur; Laborelec

in Applied Energy N. 148 (15 June 2015). - 496-505

Résumé: Battery Electric Vehicles (BEV) are considered to be a better alternative for conventional vehicles in the matter of carbon dioxide (CO2) emissions and urban air pollution reduction. Life Cycle Assessment (LCA) is a widely used methodology to quantify and compare the environmental impacts of vehicle technologies. In this study, we compare the life cycle environmental emissions of CO2 equivalent (CO2e), sulfur dioxide (SO2), nitrogen oxides (NOX) and particulate matters (PM) of the BEV with the petrol and diesel vehicles. Unlike many other literatures, this study uses the real-world energy consumption data for the environmental assessment. In addition, this study explores the possible impact of the short term and long term fluctuations in the electricity mix and the vehicle charging profile, on the life cycle emissions performance of BEV. The influence of charging profile on the well-to-tank (WTT) emissions (i.e. emissions associated with electricity production) of BEV is discussed by using hourly emissions and different possible peak and off-peak charging time frames. The results of this study proves off-peak charging is a better option to reduce the life cycle emissions, compared to peak charging. When a BEV is charged during off-peak hours instead of peak hours, the well-to-tank CO2, SO2, NOX and PM emissions per km can be reduced significantly. Also, this study emphasizes the importance of taking driving behaviors of users and auxiliary energy consumption into account. This aspect is analyzed by comparing the empirical energy consumption and the corresponding WTT emissions of BEV, with the New European Driving Cycle (NEDC) standard values. The results reveal that the auxiliary energy consumption is responsible for, nearly a third of the WTT emissions.

A modelling approach for the assessment of an air-dryer economic feasibility for small-scale biomass steam boilers [Article]

De Fusco, L., Auteur; Jeanmart, H., Auteur; Blondeau, Julien, Auteur; Laborelec. - Elsevier, 13/02/2015.

Résumé : Fuel drying is an energetically and economically expensive pretreatment process, which may not be worth the investment in the case of small-scale generation plants. This paper presents an investigation on the air dryer feasibility to enhance the operation of biomass steam boiler. In the proposed approach, the external drying technology using preheated air and the biomass steam production system is modelled in terms of energy and an economical analysis. A focus is given to the system size influence on the dryer economic suitability: the smallest size of the biomass combustion system for which fuel drying is a suitable solution, from the economic point of view, is computed. In the computations, the heat used for drying is assumed to be part of the cost for operating the dryer and the thermal balance of the system is assumed to be previously verified. According to the model results, if the steam production plant operational time is above 8000 h/y, wood chips drying is feasible if the system size is larger than 1.78 tdaf/h of fuel processed.

Published in : Fuel Processing Technology (In Press)

Online Corrosion Monitoring in a Postcombustion CO2 Capture Pilot Plant and its Relation to Solvent Degradation and Ammonia Emissions [Article]

/ Mertens, Jan, Auteur; De Vroey, Séverine, Auteur; Khakharia, Purvil, Auteur; Huizinga, Arjen, Auteur; Fernandez, Eva Sanchez, Auteur; Srinivasan, Sridhar, Auteur; Vlugt, Thijs J.H., Auteur; Goetheer, Earl, Auteur; Laborelec. -

American chemical Society (ACS), 20/04/2015.

Résumé : Corrosion in amine treating plants is known to cause integrity failures, plant shutdown, costly repairs, and so forth. The use of an amine treatment system for postcombustion CO2 capture brings additional challenges in terms of the flue gas quality, flue gas composition, operating conditions, scale of operation, and so forth. These differences are expected to have a significant impact on the overall well-being of the plant and the maintenance strategy over its lifetime. The degradation of solvent, by oxidative and thermal degradation pathways, leads to the formation of various degradation products which are known to be corrosive. The oxidative degradation of amine leads to the formation of ammonia which can be emitted to the atmosphere in the treated flue gas stream. This study aims at verifying the interrelation between (1) solvent degradation, (2) corrosion, and(3) NH3 emissions, based on two test campaigns of over 1500 operating hours, in a CO2 capture pilot plant. An online tool for real-time corrosion monitoring, SmartCET, is presented and compared with offline corrosion coupon. The different process and operating conditions such as the change in the flue gas composition, start-up and shutdown, and solvent replacement were correlated with the variations in the corrosion parameters (general corrosion rate, pitting factor, and corrosion mechanism indicator (CMI)), for both campaigns. The three parameters showed only a small increase for most part of both the campaigns(>75 days), and followed a similar trend. However, during both the campaigns, a rapid increase of all the three parameters was observed. In one of the campaigns, the three parameters increased by about 2 orders of magnitude in a time period of only about 20 days, which points toward an autocatalytic out of control solvent chemistry. The common characteristic before the onset of autocatalytic solvent chemistry, is the re-start-up of the pilot plant after an extended period of shutdown. On the basis of these tests, the use of an online corrosion monitoring tool will enable long-term steady state operation of a full scale postcombustion CO2 capture plant.

Published in : Industrial & Engineering Chemistry Research, 2015, 54 (19), pp 5336–5344

Results of fly ash quality for disposal options from high thermal shares up to pure biomass combustion in a pilot-scale and large scale pulverized fuel power plants [Article]

/ Fuller, A., Auteur; Carbo, M., Auteur; Maier, J., Auteur; Scheffknecht, G., Auteur; Savat, Patrick, Auteur; Laborelec.

Résumé : This work evaluated fly ash quality from combustion of high thermal shares of biomass fuels. Woody biomass was (co)combusted in an industrial scale pulverized fuel power plant, and a herbaceous biomass was co-combusted in a pilot-scale test facility. Ashes from the electrostatic precipitator were collected and evaluated for chemical compounds, leaching behavior, and mechanical properties. Results from the large-scale industrial pulverized fuel showed the ashes still had good reactivity and mechanical properties according to EN450-1, which is a good unexpected occurrence regarding strength development. Results from the pilot-scale test facility showed that a herbaceous biomass co-fired up to 50% thermal share does not seem to have any negative impact on existing fly ash utilization routes. It is concluded that co-firing clean woody biomass at a very high thermal share and co-firing a high thermal share of a herbaceous biomass with lignite would not change current utilization practices. In practice ashes from high thermal shares are not used due to safeguards in standards form a lack of experience from enough performance testing. Thus, the findings can lead to support for standards that incorporate other assessment methods for biomass fly ash utilization requirements.

Published in : Renewable energy, Vol. 75, March 2015

Sea water ingress during the commissioning of an USC power plant

/ Senécat, Anthony, Auteur; Ertryckx, Roger, Auteur; Laborelec

in VGB PowerTech Vol. 95 - N. 6 [25/06/2015]. - 69-72

Résumé: During the commissioning of an ultra supercritical coal-fired power plant an event occurred in the condenser which resulted in a serious ingress of seawater in the water-steam cycle. The plant was operated more than 10 hours with this sea water ingress leading to uncontrolled chemistry in the whole water-steam cycle, except for the steam turbine which was in bypass mode. In the aftermath of the incident, a root cause analysis was performed to determine the origin of the pollution and to understand the chemistry trends during the incident. Questions about the integrity of the boiler were raised as the incident occurred a few weeks after the thermal passivation so the protective oxide layer might have been washed out during the incident. Some tube samples were extracted for metallographic examinations.

The new 200 MWe wood-fired CFBC at Polaniec/Poland /

Van Dijen, Frans, Auteur; Gennart, Héloise, Auteur; Laborelec

in VGB PowerTech Vol. 95 - N. 1/2 [17/03/2015]. - 48-51

Note de contenu: GDF SUEZ ENERGY operates a new CFBC plant with a capacity of about 200 MWe at the Polaniec site in Poland. The main fuel is wood, especially wet wood chips. The boiler was supplied by Foster Wheeler and was connected to the exiting/upgraded steam turbines, generator and condenser. First operating experience is presented and proposals are made as regards the future and potentials of CFBC which can be further improved and advanced. Particularly existing experience is to be incorporated into new designs and constructions. Besides, new R&D projects are to be realised.

Understanding aerosol based emissions in a Post Combustion CO2 Capture process : Parameter testing and mechanisms

/ Khakharia, Purvil, Auteur; Brachert, Leonie, Auteur; Mertens, Jan, Auteur; Anderlohr, Christopher, Auteur; Huizinga, Arjen, Auteur; Fernandez, Eva Sanchez, Auteur; Schallert, Bernd, Auteur; Schaber, Karlheinz, Auteur; Vlugt, Thijs J.H., Auteur; Goetheer, Earl, Auteur; Laborelec

in International Journal of Greenhouse Gas Control N. 34 (March 2015). - 63-74

Résumé: tSolvent emissions from a Post Combustion CO2Capture (PCCC) process can lead to environmental hazards and higher operating cost. Aerosol based emissions in the order of grams per Nm3have been reported from PCCC plants. These emissions are attributed to the presence of particles such as sulphuric acid aerosol droplets in the flue gas. Recently, we confirmed the relation between particle number concentration in the inlet flue gas and aerosol based emissions of monoethanolamine (MEA) as the solvent. The operating parameters and especially the presence of CO2were found to influence the extent of aerosol based emissions. In this study, the following parametric experimental tests were performed in a mini CO2capture plant: changing the lean solvent temperature, the pH of the lean solvent, and the CO2concentration in the flue gas. Moreover, other commonly used CO2capture solvents, a mixture of 2-amino-2-methyl-propanol(AMP) with piperazine (Pz), and AMP with potassium taurate (KTau), were evaluated for their potential for aerosol formation. Increasing the temperature of the lean solvent resulted in a lowering of the amine emissions. Aerosol based emissions were observed only at a relatively high lean pH. As the CO2content of the flue gas was reduced from 12.7 to 0.7 vol.%, a maximum in the emissions was observed at 6 vol.% of CO2. Aerosol based emissions for both AMP (1500–3000 mg/Nm3) and Pz (200–400 mg/Nm3) were measured, while no aerosol based emissions were observed for AMP-Ktau as a solvent even in the presence of sulphuric acid aerosols in the flue gas. The ratio of AMP:Pz emissions was found to be much lower in the presence of aerosols (5–12) as compared to only volatile emission (∼26). This indicated that Pz has a preference to be in the aerosol phase over AMP. Three aspects were found to be important for aerosol based emissions in a CO2capture absorber: (i) the particle number concentration, (ii) the supersaturation, and (iii) the reactivity of the amine. These observations add to the existing understanding of aerosol formation and growth by heterogeneous nucleation in counter-current gas liquid absorption processes, by considering the reactivity of the components.

Technical Publications 2014

Multiscale Technique for Biomass Particle Combustion : Integration of a 2D particle combustion module in ANSYS Workbench

Blondeau, Julien, Auteur; Boland, A., Auteur; Boucquey, A., Auteur;

Laborelec. - 19/03/2014. Published in : Modeling Combustion and Reacting Flows - A joint ANSYS & Dacolt Seminar

Two years behind the wheel of electric vehicles: a unique monitoring experience in Belgium

De Vroey, Laurent, Auteur; Laborelec in Revue E tijdschrift Vol. 129 - N. 4 (octobre/oktober - novembre/november - décembre/.december 2013). - 11-14

The first new generation electric cars were introduced in Belgium by the end of 2010. Laborelec and Electrabel have implemented and in-depth monitoring in the first available Peugeot iOn cars, with a technical support from the Vrije Universiteit Brussel. Battery current, voltage and state-of-charge are monitor, as well as odometer data, instant speed, GPS coordinates and ambient temperature. The tests were started in June 2011 and are still running. This initiative is the first of its kind in Belgium.

Different driving styles, trip profiles, type and intensity of use were observed, leading to different energy patterns. Seasonal impacts on battery efficiency and auxiliary consumption are taken into account. This gives valuable information that cannot be obtained from theoretical, e.g. NEDC (New European Driving Cycle) measuring conditions.

In this paper, some key figures are given to get an insight on the users' and cars' behavior. Feedback elements from the users are given after two years of use. 

The hourly life cycle carbon footprint of electricity generation in Belgium, bringing a temporal resolution in life cycle assessment

Messagie, Maarten, Auteur; Mertens, Jan, Auteur; Oliveira, Luis, Auteur; Rangaraju, Surendraprabu, Auteur; Sanfelix, Javier, Auteur; Coosemans, Thierry, Auteur; Van Mierlo, Joeri, Auteur; Macharis, Cathy, Auteur; Laborelec in Applied Energy N. 134 (1 December 2014). - 469-476

In the booming research on the environmental footprint of, for example, electrical vehicles, heat pumps and other (smart) electricity consuming appliances, there is a clear need to know the hourly CO2 content of one kW h of electricity. Since the CO2 footprint of electricity can vary every hour; the footprint of for example an electric vehicle is influenced by the time when the vehicle is charged. With the availability of the hourly CO2 content of one kW h, a decision support tool is provided to fully exploit the advantages of a future smart grid. In this paper, the GWP (Global Warming Potential) per kW h for each hour of the year is calculated for Belgium using a Life Cycle Assessment (LCA) approach. This enables evaluating the influence of the electricity demand on the greenhouse gas emissions. Because of the LCA approach, the CO2 equivalent content does not only reflect activities related to the production of the electricity within a power plant, but includes carbon emissions related to the building of the infrastructure and the fuel supply chain. The considered feedstocks are nuclear combustible, oil, coal, natural gas, biowaste, blast furnace gas, and wood. Furthermore, renewable electricity production technologies like photovoltaic cells, hydro installations and wind turbines are covered by the research. The production of the wind turbines and solar panels is more carbon intensive (expressed per generated kW h of electricity) than the production of other conventional power plants, due to the lower electricity output. The overall average GWP per kW h is 0.184 kg CO2eq/kW h. Throughout the 2011 this value ranges from a minimum of 0.102 kg CO2eq/kW h to a maximum of 0.262 kg CO2eq/kW h depending on the timing. 

ELPI+ measurements of aerosol growth in an amine absorption column

Mertens, Jan, Auteur; Brachert, Leonie, Auteur; Desagher, Dominique, Auteur; Thielens, Marie-Laure, Auteur; Khakharia, Purvil, Auteur; Goetheer, Earl, Auteur; Schaber, Karlheinz, Auteur; Laborelec in International Journal of Greenhouse Gas Control N. 23 (April 2014). - 44-50

Recently, studies have appeared pointing out that aerosols can dominate the total amine emission fromamine based PCCC pilot plant scale installations. For the design of countermeasure types (upstream ordownstream of the PCCC installation), it is crucial to have an idea of the aerosol size distribution andnumbers entering or leaving the absorber. This study is the first to present this kind of data and shouldserve future installations when designing aerosol emission countermeasures. H2SO4aerosols entering the absorber are observed to be extremely small 

A Norm Behavior Based Deterministic Methodology for Demand Response Base Lines

Vanthournout, Koen, Auteur; Foubert, Wim, Auteur; Stuckens, Catherine, Auteur; Robben, Bert, Auteur; Premereur, Geert, Auteur; Laborelec. - [S.l.] : Power Systems Computation Conference (PSCC), 18/08/2014. 18th Power Systems Computation Conference (18/08/2014)

A Norm Behavior Based Deterministic Methodology for Demand Response Base Lines

One of the keystones required to bring demand response from academia and pilots to the industry and the market, is a reliable demand response base line methodology to measure the performance of the DR resources and for DR billing settlement. However, most base line methodologies proposed in the literature use statistical analysis of historic consumption data when no demand response is active. The availability of such data drops as demand response is more continuously used.

We propose and define a base line methodology that builds on a norm behavior convention, where this norm behavior can be derived from the status and configuration data of the flexible devices, rather than from historic measurements. This is illustrated for postponable and buffered appliances.

Norm behavior base lines can also be used for interfacing between aggregator and user of the flexibility. This has been deployed in the Linear residential demand response pilot to realize intraday balancing. The first results show that the base line methodology operates as expected. They also show the asymmetry of the flexibility offered by postponable non-interruptable white good appliances.

Water footprinting of electricity generated by combined cycle gas turbines using different cooling technologies

Mertens, Jan, Auteur; Prieur-Vernat, Anne, Auteur; Corbisier, Dominique, Auteur; Favrot, Elsa, Auteur; Boon, Gustaaf, Auteur; Laborelec in Journal of Cleaner Production Vol. 86 (January 2015). - 201-208

Efforts undertaken for reducing environmental impacts of energy production have been primarily focused on carbon reduction while the fact that energy production also requires water has been largely overlooked. During the last decade, and despite the fact that global warming still remains today the focus of many environmental evaluations, water scarcity issues have increasingly received attention. Despite the fact that recently, an increasing demand for large industrial companies to calculate and report on their water footprint exists, water resources have only recently been addressed in life cycle assessment (LCA) and their assessment still lacks wide application. The paper presents a practitioner's experience with respect to the application of three recently developed water footprinting methodologies that are considered as current-state-of-the-art. The methods are applied with as objective the estimation of the water footprint of combined cycle gas turbines with different cooling technologies. The study reveals that absolute values of water footprints (Leq. kWh 1) are very different among methods and therefore results are not directly comparable in terms of their absolute results. In contrast, ranking among power plants agree for the different methods when large differences in water consumption/impact exist. However, the ranking may differ between different methods when differences are small. It therefore remains impossible to select one method as the preferred method to use. This study therefore serves as support to the recently emerging working groups (eg. WULCA) that aim at harmonizing the different existing methodologies. 

Weldability assessment and high temperature properties of advanced creep resisting austenitic steel DMV304HCu

Vekeman, Johan , Auteur; Huysmans, Staf, Auteur; De Bruycker, Evy, Auteur; Laborelec in Welding in the World Vol. 58 - N. 6 (November 2014). - 873-882

The modern (USC PP) applying the 600 °C technology require advanced austenitic stainless steels in superheater/reheater systems in order to cope with the increased steam parameters. Different grades of austenitic stainless steels have been developed by increasing Cr contents, alloying with stabilizing and precipitating elements as well as thermomechanical heat treatments resulting in high creep rupture strengths and improved oxidation/corrosion resistance. In the context of a collaborative research project, DMV304HCu (X10CrNiCuNb18-9-3) has been selected. The main focus of the research project was on characterization and weldability assessment. As a result, the base metal under investigation was compared with governing code cases and specifications. Base metal chemical composition, microstructures, mechanical properties, reheat cracking sensitivity, hot ductility as well as creep rupture strengths have been investigated. Aweldability assessment, including thermal simulation and welding procedure qualifications, has been performed to establish parameter windows for similar and dissimilar welding. Dissimilar welding between Grade 92 and austenitic stainless steel tubes has been performed. The project also took the opportunity to investigate the behavior of a recently developed gas tungsten arc welding (GTAW) P87 consumable for dissimilar welding. Cross-weld creep rupture testing has been conducted for both similar and dissimilar welding, and aging tests addressed microstructural stability. 

(Remaining) Lifetime Assessment of Power Plant Parts to Safely Exploit their Full Lifetime Potential and Reduce OPEX

Dutoit, Michael, Auteur; Thielemans, Fabien, Auteur; Degive, Xavier, Auteur; Laborelec. - 2014. POWERGEN Middle East 2014 (12/10/2014)

High reliability and profitability are two important aspects of the current power plants in the Middle East. At the same time, newer power plant technologies put higher demands on the different power plant parts. So (remaining) lifetime assessment of different components plays a crucial role in today’s power plant management. In particular, lifetime assessment makes sense for most parts being operated at high temperature, where creep damage accumulates, like boiler tubing and gas and steam turbine blading. A high-quality lifetime analysis helps power plant owners to make decisions concerning life extension or repair of theoretically end-of-life components. It also plays an important role in planning maintenance intervals and in root cause failure analyses. As materials and/or parts geometry become more and more sophisticated, the understanding of materials degradation and the implementation of advanced testing techniques becomes of the utmost importance in lifetime analysis. A combination of theoretical considerations, calculations and material testing is often necessary. With this paper, GDF Suez Laborelec discusses some important lifetime assessment considerations, and the advanced methodologies (e.g. parametric model-based creep data processing) and testing technologies (e.g. miniature creep testing) that can be used to deal with them. The considerations are illustrated with real case studies, like the lifetime extension of E-class gas turbine blading and the premature lifetime exhaustion of T91 boiler tubes. 

Led-verlichting en kwaliteit

Van Heur, Rob, Auteur;
 Laborelec in LED Magazine Vol. 2 - N. 4 (December 2014). - 44

Evaluation of the DMX process for industrial pilot demonstration - methodology and results

Raynal, Ludovic, Auteur; Briot, Patrick, Auteur; Dreillard, Matthieu, Auteur; Broutin, Paul, Auteur; Mangiaracina, Angela, Auteur; Salghetti Drioli, Benedetta, Auteur; Politi, Monia, Auteur; La Marca, Cristiana, Auteur; Mertens, Jan, Auteur; Thielens, Marie-Laure, Auteur; Laborie, Géraldine, Auteur; Normand, Laurent, Auteur; Laborelec.

The SP3 Subproject of the OCTAVIUS EU FP7 project was dedicated to the demonstration of the DMX CO2 capture process,developed by IFP Energies nouvelles (IFPEN) and licensed by PROSERNAT, on the 3.5 MWe equivalent industrial pilot of ENEL at Brindisi. The DMX process is based on the particular property of demixing solvents to form, for specific CO2 loadings and temperature conditions, two immiscible liquid phases. The light phase being almost free of CO2, only the high capacity heavy phase is sent to the stripper, which makes possible energy savings but also requires an adapted process flow scheme and extra equipment. Prior to launch the corresponding retrofit and perform the pilot tests, two conditions were settled. First, a quantitative evaluation of the process must show a significant interest in comparison with the benchmark MEA 30wt.%. To evaluate this first conditions, 24 criteria were considered. Second, an acceptable cost for the retrofit of the existing industrial pilot, determined from a Front End Engineering and Design (FEED) study must be obtained. Most of this paper deals with the evaluation of these two conditions which ended in November 2013 and a small section is dedicated to the FEED study. It is shown that most of the parameters considered for the process evaluation are in good agreement with the initial targets. The proposed evaluation methodology could be used for any new process prior to demonstration.

Published in : Energy Procedia 63 (2014) 6298 - 6309 - ELSEVIER

Predicting Aerosol Based Emissions in a Post Combustion CO2 Capture Process Using an Aspen Plus Model

Khakharia, Purvil, Auteur; Mertens, Jan, Auteur; Vlugt, Thijs J.H., Auteur; Goetheer, Earl, Auteur; Laborelec. - [S.l.] : Elsevier, 01/12/2014. - 911 – 925. Industrial scale implementation of post combustion CO2 capture (PCCC) can be hindered by solvent emissions due to its impact on the environment and the operating costs. The issue of aerosol based emissions has only been recently reported for a PCCC process and very little fundamental knowledge is available in the scientific community on this topic. Therefore, it is important to understand the mechanism of aerosol formation and growth so that appropriate countermeasures can be applied in reducing the total emissions. In this study, a simplified methodology is presented for predicting aerosol based emissions from a CO2 capture

column of a PCCC process. The basis of this methodology is to split the counter-current gas-liquid interaction from the cocurrent gas-aerosol interaction. The absorption column is discretised into multiple alternating gas-liquid and gas-aerosol sections in Aspen Plus with an assumption that aerosols behave as a continuous phase rather droplets. The degree of supersaturation, which is important for aerosol formation and growth, is calculated along the column. The effect of the changes in parameters of the PCCC plant, such as the CO2 content of the inlet flue gas, the lean solvent temperature and the lean solvent loading on aerosol based emissions are investigated. The aerosol based emissions follows the trend of the supersaturation ratio in the absorber column.

Published in : Energy Procedia 63 ( 2014 ) 911 – 925 - ELSEVIER

Predicting amine mist formation based on aerosol number concentration and size measurements in flue gas

Mertens, Jan, Auteur; Brachert, Leonie, Auteur; Desagher, Dominique, Auteur; Schallert, Bernd, Auteur; Khakharia, Purvil, Auteur; Goetheer, Earl, Auteur

Amine based solvent used for CO2 capture can be lost during the process due to: degradation, vaporization, mechanical losses and aerosol (mist) formation. Only recently, studies have appeared pointing out that aerosols can dominate the total amine emission at pilot plant scale behind coal fired power plants. Future full scale amine scrubber installations will be imposed emission limit values (ELV) for a number of components including NH3 and the amine itself. Most likely these ELV will be expressed as maximum concentrations tolerated in the CO2 poor flue gas leaving the stack so it is important to prevent or cure amine aerosol emission. The study presents a novel combination of two existing measurement techniques, that measure: (i) amine emissions from the top of the absorber using FTIR and (ii) PSD of the incoming flue gas using the ELPI+. The study is the first to show how combining these two measurement techniques allows to predict the presence or absence of mist formation. This hypothesis is based on information obtained during several measurement campaigns on different pilot plants.

Language : English Keywords : amine emission;aerosol;mist;Fourier Transformed Infra Red (FTIR);Electrical Low Pressure Impactor (ELPI)

Published in : Energy Procedia 63 ( 2014 ) 893 – 901 - ELSEVIER

A wet electrostatic precipitator (WESP) as countermeasure to mistformation in amine based carbon capture

Mertens, Jan, Auteur; Anderlohr, Christopher, Auteur; Rogiers, Pieter, Auteur; Brachert, Leonie, Auteur; Khakharia, Purvil, Auteur

in International Journal of Greenhouse Gas Control N. 31 (December 2014). - 175–181

This study is to our knowledge the first to evaluate the potential of a wet electrostatic precipitator (WESP)to prevent aerosol formation issues inside amine based carbon capture installations. A WESP is a suitableoption since this study proves that it is very efficient for the removal of the mist precursors inside the fluegas to be treated. Although a significant capital investment cost may be involved, energy requirements (i.e.low pressure drop), maintenance and therefore operational costs are expected to be very low. However,it is shown here that the WESP must be installed at the right location, i.e. the flue gas to be treated mustcontain no or very low levels of SO2. The reason is that the WESP’s aerosol removal efficiency decreasesstrongly in the presence of SO2gas and in a certain range also with increasing voltages. This limits thepositive effect that the WESP has on reducing the MEA emissions from the absorber since a large numberof mist formation precursors remain in the flue gas. In the presence of SO2, a WESP can actually produceH2SO4aerosols. It is shown that these newly created aerosols are very small (low nanometre range).This information is very important for future pilot and demo amine carbon capture installations thinkingof implementing a WESP as countermeasure to aerosol formation issues. It implies that no or very lowlevels of SO2should still be present in the flue gas before entering the WESP. Since most of the aminecarbon capture installations have a pre-scrubber (usually using NaOH to remove residual SO2in the flueleaving the power plant’s FGD) in front of their amine absorber, the WESP must be installed behind thispre-scrubber and not in front of it.

Language : English Keywords : Wet electrostatic precipitator;Monoethanolamine;Emission measurement;Aerosols;Mist;Post combustion carbon capture

Phenomenology of Hydrogen Flaking in Nuclear Reactor Pressure Vessels

De Bruycker, Evy, Auteur; De Vroey, Séverine, Auteur; Stubbe, Jacqueline, Auteur; Huysmans, Staf, Auteur; Laborelec. - [S.l.] : Federal Institute for Materials Research and Testing (BAM), 01/06/2014. - pp. 439-444.

Recently, the problem of hydrogen flaking resurfaced, when internal defects were detected in the reactor pressure vessels of two Belgian nuclear power plants. These defects turned out to be hydrogen flakes formed during the fabrication of these pressure vessels. The goal of this publication is to provide important insights into the phenomenon of hydrogen flaking, the different parameters that play a role in the mechanism, as well as the typical morphology and location of these flakes. Therefore an extensive literature study was combined with a detailed metallurgical characterization of a significant number of flakes. Hydrogen flaking is a fabrication problem, which is strongly linked with segregation phenomena. A combination of a sufficient amount of hydrogen, stresses and a sensitive microstructure causes hydrogen flaking. For these reasons hydrogen flakes inside large reactor pressure vessels are found in the so-called ghost lines, which originate from segregation processes during casting.

Language : English Published in : Materials Testing, Vol. 56 - N. 6

HV/MV transformer peak load forecasting for the application demand response at an industrial site, a case study in the Netherlands

Van Lumig, Michiel, Auteur; Didden, Marcel, Auteur; Haut, Bertrand, Auteur; Luijten, Jos, Auteur; Veldman, Else, Auteur; Laborelec. - Belgium : CIRED, 11/06/2014.

CIRED workshop 2014: Challenges of Implementing Active Distribution System Management (11/06/2014)

Research to use Demand Response (DR) for reducing the load of grid assets. To implement DR, knowledge is needed of the congestion and of DR possibilities. This paper describes a method to forecast the load and peak moments of a HV/MV transformer. With this forecast will be evaluated how DR can help to reduce the load of the HV/MV transformer in case of potential overloading.

Language : English

Technical Publications 2013

Comparison of Gamma-Radiation Induced Attenuation in Al-Doped, P-Doped and Ge-Doped Fibres for Dosimetry

Alexey V. Faustov; A. Gusarov; Marc Wuilpart; Patrice Megret; Andrei A. Fotiadi; Leonid B. Liokumovich; I. O. Zolotovskiy; Alexandr L. Tomashuk; Tanguy de Schoutheete

Nuclear Science, IEEE Transactions on , vol.60, no.4, pp.2511,2517, Aug. 2013

Abstract: We have investigated radiation induced absorption in Al-doped, P-doped and Ge-doped optical fibres under Co source gamma-radiation up to a total dose of 71 kGy at two temperatures 30 and 80 C. The Al-doped and P-doped fibres demonstrated high radiation sensitivity required for the optical fibre dosimetry. The RIA response to temperature increase from 30 to 80 C depended on the dopant. In Al-doped fibres the absorption level decreased by 25% whereas in P-doped fibres it increased by at least 10%. For comparison we also tested standard telecom-grade Ge-doped fibres. Such fibres demonstrated a monotonous rise of the RIA during the whole irradiation with a small decrease of sensitivity at the higher temperature

Detection and monitoring of shorted field windings in a large 4-pole generator rotor through vibration analysis : a case study

Koenraad De Bauw; Mirza Osmanovic; Kris Matthys

SIRM 2013 - 10th International Conference on Vibrations in Rotating Machines, Berlin, Germany, 27. February 2013

Abstract: Laborelec is responsible for the follow-up of the vibration behaviour of a fleet of more than 100 shaft lines within the power generation division of GDF-Suez. Based on an experience of more than 20 years with continuous vibration monitoring in a close partnership with the power plants, Laborelec has been able to build up expertise in the analysis and solution of vibration problems on large turbomachinery. This paper describes a case study of increased vibrations of a 1000 MW generator with a 4-pole rotor in a nuclear power plant, due to shorted field windings in the rotor. Conventional detection methods for shorted field windings could not be easily applied for this unit. A comprehensive analysis of the vibration behaviour and an access to the complete history of the rotor’s operation and maintenance made it possible to identify the presence of shorted rotor field windings as the main cause of the increased vibrations. In order to maintain a reliable operation of the unit until the next opportunity to exchange the rotor, a detailed monitoring program was set up and measures were taken to reduce the vibrations on the unit and its peripheral equipment to acceptable levels. These measures included a field balancing correction, supported by a rotor dynamic analysis of the shaft train. The rotor will be exchanged at its next overhaul opportunity. The detailed analysis and monitoring enabled the owner to plan the rotor exchange well in advance and thus to reduce the related costs of the intervention.

Investigation of aerosol based emission of MEA due to sulphuric acid aerosol and soot in a Post Combustion CO2 Capture process

Purvil Khakharia; Leonie Brachert; Jan Mertens; Arjen Huizinga; Bernd Schallert; Karlheinz Schaber; Thijs J.H. Vlugt; Earl Goetheer,

International Journal of Greenhouse Gas Control, Volume 19, November 2013, Pages 138-144

Abstract: The prevention of emissions of amine species is of high importance for the overall sustainability and performance of Post Combustion CO2 Capture facilities. There is a clear understanding of amine emissions based on volatility in the treated flue gas. Emission via aerosols from Post Combustion CO2 Capture facilities has only been pointed out recently. Thus, there is little knowledge about emission via aerosols in contrast to emission based on volatility. It has been found that flue gas quality plays an important role for emissions caused by aerosols formation. In this work, we study the experimental assessment of the impact of flue gas quality on the level of monoethanolamine (MEA) emission via aerosols. In a dedicated test rig, effects of the flue gas components such as sulphuric acid aerosols and extremely fine particles like soot has been studied. An aerosol generator capable of producing controlled amounts of soot and dosing sulphuric acid aerosol to a mobile CO2 capture mini-plant was used as a test equipment for this study. Soot particle number concentration were in the range of 104–106 per cm3. The particle number concentration for different amount of H2SO4 aerosols were in the order of 108 per cm3. Amine emissions up to 4.3 ppmv (12 mg/N m3 for MEA) is considered to be as an upper limit for the design of a Post Combustion CO2 Capture plant. MEA emissions in the presence of soot particles were in the range of 100–200 mg/N m3 which is 2–4 times higher than baseline vapour based emissions of about 45 mg/N m3. The expected particle size of H2SO4 aerosols is well below 100 nm, while the corresponding mass concentration range is between 1 and 5 mg/m3. The MEA emissions observed due to H2SO4 aerosols were in the range of 600–1100 mg/N m3. Moreover, parametric tests have shown that besides flue gas quality, the absorber temperature profile and the presence of CO2 in the flue gas are pre-requisite for aerosol emissions. It is evident that the observed level of emissions in this study are unacceptable. Therefore, it is imperative that fundamental know-how about aerosol formation and reduction is generated in order to design appropriate counter measures.

Remote distributed optical fibre dose measuring of high gamma-irradiation with highly sensitive Al- and P-doped fibres

Alexey V. Faustov; A. Gusarov; Marc Wuilpart; Andrei A. Fotiadi; Leonid B. Liokumovich; I. O. Zolotovskiy; Alexandr L. Tomashuk; Tanguy de Schoutheete; Patrice Megret

Part of Proceedings of SPIE Vol. 8774 Optical Sensors 2013 (15-17 April 2013) ; paper 8774-2, Session 1

Abstract: We present our results on measuring distributed Radiation-Induced Attenuation (RIA) by means of a commercially available Optical Frequency Domain Reflectometry (OFDR) system. We chose four different highly gamma-radiation sensitive fibres, two of which were doped with Al and two with P. The dose rate during irradiation was about 560Gy/h. The irradiation were conducted at two temperatures of 30°C and 80°C. The irradiation at different temperature were needed for taking into account temperature dependence of the annealing speed of RIA. The RIA measurements were taken by means of two techniques. First one consisted in the spatially integrated spectral transmission detection using an Optical Spectra Analyser (OSA) and the second was based on distributed RIA measuring by means of the OFDR. All four fibres demonstrated a high saturation-like increase of RIA with the dose up to several tens of decibels per meter detected by OSA. In case of OFDR measurements the change of the attenuation in an optical fibre resulted in a change of the slope of the corresponding Rayleigh backscattering trace which was clearly observed during the experiments. The RIA dependences measured with the OFDR were in a reasonable agreement with the measurements obtained with OSA. This allows us to use the dependences of RIA on absorption dose obtained by means of OSA for the distributed dose measuring based on the OFDR technique. We also irradiated different lengths of one of the P-doped fibers to see if it influences accuracy of the distributed dose detection. The results of the presented experiments are noteworthy since they are considered to be a basis for a dose estimation model based on RIA in which temperature oscillations are taken into account.

Small ring testing of a creep resistant material

Christopher J. Hyde; T. H. Hyde; W. Sun; Steve NARDONE; Evy De Bruycker

Materials Science and Engineering: A, Volume 586, 1 December 2013, Pages 358–366

Abstract: Many components in conventional and nuclear power plant, aero-engines, chemical plant etc., operate at temperatures which are high enough for creep to occur. These include steam pipes, pipe branches, gas and steam turbine blades, etc. The manufacture of such components may also require welds to be part of them. In most cases, only nominal operating conditions (i.e. pressure, temperatures, system load, etc.) are known and hence precise life predictions for these components are not possible. Also, the proportion of life consumed will vary from position to position within a component. Hence, non-destructive techniques are adopted to assist in making decisions on whether to repair, continue operating or replace certain components. One such approach is to test a small sample removed from the component to make small creep test specimens which can be tested to give information on the remaining creep life of the component. When such a small sample cannot be removed from the operating component, e.g. in the case of small components, the component can be taken out of operation in order to make small creep test specimens, the results from which can then be used to assist with making decisions regarding similar or future components. This paper presents a small creep test specimen which can be used for the testing of particularly strong and creep resistant materials, such as nickel-based superalloys.

The challenge of measuring sulfuric acid aerosols : Number concentration and size evaluation using a condensation particle counter (CPC) and an electrical low pressure impactor (ELPI+)

Leonie Brachert; Jan Mertens; Purvil Khakharia; Karlheinz Schaber

Journal of Aerosol Science, volume 67 (2014), pp. 21–27

Abstract: In this study, two different methods for the measurement of the sulfuric acid aerosol which is formed in wet flue gas cleaning processes have been investigated. The condensation particle counter (UFCPC, PALAS GmbH) provides information about the number concentration. With the electrical low pressure impactor (ELPI+, Dekati Ltd.) also the size evaluation is possible. Both measurement methods reveal number concentrations above 108 cm−3 under well controlled conditions in a pilot plant and the good conformance of the both methods is shown. With the ELPI+ the effect of dilution on the size of the volatile aerosol can be observed. The predicted trend of an existing simulation tool can be verified: the higher the sulfuric acid concentration, the larger are the droplet sizes. The number concentration, however, doesn´t change considerably when altering the sulfuric acid concentration.

The Influence of Allocation on the Carbon Footprint of Electricity Production from Waste Gas, a Case Study for Blast Furnace Gas

Maarten Messagie; Fayçal Boureima; Jan Mertens; Javier Sanfelix; Cathy Macharis; Joeri Van Mierlo

Energies 2013, 6, pp. 1217-1232

Abstract: Producing electricity from waste gas is an after treatment for waste gas while recovering the energy content. This paper addresses the methodology to calculate the effect that waste gas energy recovery has on lowering the impact of climate change. Greenhouse gases are emitted while burning the waste gas. However, a thorough study should include the production of the feedstock as well as the production of the infrastructure. A framework is developed to calculate the environmental impact of electricity production from waste gas with a life cycle approach. The present paper has a twofold purpose: to assess the climate change impact of generating electricity with blast furnace gas (BFG) as a waste gas from the steel industry; and to establish a sensitivity assessment of the environmental implications of different allocation rules.

Understanding ethanolamine (MEA) and ammonia emissions from amine based post combustion carbon capture : Lessons learned from field tests

Jan Mertens; Hélène Lepaumier; Dominique Desagher; Marie-Laure Thielens

International Journal of Greenhouse Gas Control, Volume 13, March 2013, pp. 72-77

Abstract: The study discusses the origin and driving factors of the ammonia (NH3) and ethanolamine (MEA) emissions from post combustion carbon capture (PCCC) pilot installations. The objective of this research is not presenting PCCC emission values as such but presenting the current understanding of the different emission processes based on pilot plant FTIR measurements. NH3 is being continuously produced as a result of the oxidative degradation of MEA. The study shows that its emission level is closely correlated to the solvent metal ion concentration. A good solvent chemistry in which metal ion concentrations are kept low is required to minimise NH3 emissions. The fluctuating behaviour of the MEA emissions is found to be related to mist (aerosol) formation phenomena. Whether and to what extent mist is formed depends to a large extent on the flue gas composition upstream the CO2 capture plant and on the carbon capture pilot plant's design and operating conditions. Preliminary tests suggest that a single water wash is efficient for the removal of gaseous MEA emissions but may not be suitable for the removal of the submicron mist emissions.

Water availability footprint of electricity production

Anne Prieur-Vernat; Jan Mertens

Life Cycle Management conference

Abstract: Accounting for impacts on water resources due to power production is needed to have a complete view of its environmental performance. As part of the periodically updated Life Cycle Assessment on the electricity produced by its power plants, GDF SUEZ has assessed the water availability footprint of its 2011 electricity production with the method developed by Boulay et al. in 2011. The purpose of this study is to analyze the impact associated to water use for electricity production, including both water used at the power plant and water used for the supply of fuels. Data collected for the environmental reporting of all GDF SUEZ power plants have been used and the water use is detailed by source (surface or ground water) and by use within the power plant (cooling or industrial). The actual yearly average efficiency of each power plant as well as the location of the power plants is considered into the modeling. Around 400 production sites are included in the modeling, located in 36 different countries around the world. Background data have been taken from the Waterdatabase developed by Quantis International. The outcomes of the study show that background processes (supply chains of the fuel used and infrastructures to a lesser extent) have an important contribution to the water availability footprint: whereas they represent 30% of the total freshwater consumed per kWh produced, their contribution reaches 44% of the water availability footprint. This study also demonstrate that impacts related to water use are highly sensitive to the electricity generation technology, but for a given technology, the results show an important variation of water availability footprint with the regional distribution: as an example, the specific fresh water consumption for the production of one kWh electricity in GDF SUEZ combined cycle gas turbines (CCGT) in Benelux & Germany is three times lower than for CCGT in North America, but their impact is two and a half time higher, due to local conditions. Those results are an interesting basis that can be used to define action plans at the Group level towards a better management of local water resources and of the water and energy nexus.

Technical Publications 2012


Understanding ethanolamine (MEA) and ammonia emissions from amine based post combustion carbon capture: Lessons learned from field tests

Jan Mertens, Helene Lepaumier, Dominique Desagher, Marie-Laure Thielens

International Journal of Greenhouse Gas Control, Volume 13, March 2013, Pages 72-77, ISSN 1750-5836, 10.1016/j.ijggc.2012.12.013.

Abstract: The study discusses the origin and driving factors of the ammonia (NH3) and ethanolamine (MEA) emissions from post combustion carbon capture (PCCC) pilot installations. The objective of this research is not presenting PCCC emission values as such but presenting the current understanding of the different emission processes based on pilot plant FTIR measurements. NH3 is being continuously produced as a result of the oxidative degradation of MEA. The study shows that its emission level is closely correlated to the solvent metal ion concentration. A good solvent chemistry in which metal ion concentrations are kept low is required to minimise NH3 emissions. The fluctuating behaviour of the MEA emissions is found to be related to mist (aerosol) formation phenomena. Whether and to what extent mist is formed depends to a large extent on the flue gas composition upstream the CO2 capture plant and on the carbon capture pilot plant's design and operating conditions. Preliminary tests suggest that a single water wash is efficient for the removal of gaseous MEA emissions but may not be suitable for the removal of the submicron mist emissions.

Keywords: Ethanolamine; Ammonia; Gaseous emission measurement; Aerosols; Mist; Post combustion carbon capture; Fourier Transform Infra Red (FTIR)

Het gebruik van flexibiliteit om de energierekening van bedrijven te reduceren

Marcel Didden, Laborelec

Gestion de l’énergie et efficacité énergétique : exemples pratiques d’applications dans l’industrie, les bâtiments et le résidentiel. | Energiebeheer en energie‐efficiëntie: praktische voorbeelden van toepassingen in de industrie, in gebouwen en privéwoningen (23 avril 2013 | 23 april 2013)

The Smart Home Energy Lab: the residential customer stands up!

Rafael Jahn, Laborelec

Gestion de l’énergie et efficacité énergétique : exemples pratiques d’applications dans l’industrie, les bâtiments et le résidentiel. | Energiebeheer en energie‐efficiëntie: praktische voorbeelden van toepassingen in de industrie, in gebouwen en privéwoningen (23 avril 2013 | 23 april 2013)

Measurement of the force induced by thermal expansion of conductor of MV cables and impact on MV joints

B Hennuy, Laborelec, Linkebeek, Belgium, F Steennis, Kema, Arnhem, Netherlands, B Aerns, T van Rijn, Liander, Arnhem, Netherlands, P Oosterlee, Delta Netwerkbedrijf, Middelburg, Netherlands, P Leemans, Eandis, Melle, Belgium , P Soepboer, Enexis, Rosmalen, Netherlands, R Meier, Lovink, Terborg, Netherlands, E de Ridder, Nexans, Erembodegem, Belgium, H Grandjean, Ores, Louvain-La-Neuve, Belgium, M Van Den Berg, Sibelga, Brussels, Belgium, P Buys, Stedin, Rotterdam, Netherlands, L Bokma, Westland Infra, Poeldijk, Netherlands

CIRED 2013 (10-13 June 2013), paper 0128 (session 1)

Partial discharge monitoring on MV switchgear

M De Witte, Y Tits, M Arens, Laborelec, Linkebeek, Belgium, A François, Ores, Wallonia, Belgium, M Van Den Berg, Sibelga, Brussels, Belgium, J Van Slycken, Eandis, Flanders, Belgium

CIRED 2013 (10-13 June 2013), paper 0393 (session 1)

Lack of standardization concerning interfaces between network equipments

Y L Tits, M Arens, Laborelec, Linkebeek, Belgium, A François, Ores, Louvain la Neuve, Belgium, W De Maesschalck, Eandis, Melle, Belgium, M Van Den Berg, Sibelga, Brussels, Belgium

CIRED 2013 (10-13 June 2013), paper 0541 (session 1)

Ageing and improvement of LV underground extruded cables systems

Q De Clerck, B Hennuy, Laborelec, Linkebeek, Belgium, P Leemans, Eandis, Melle, Belgium, M Van Den Berg, J Dept, Sibelga, Brussel, Belgium, H Grandjean, Ores, Marche-En-Famenne, Belgium

CIRED 2013 (10-13 June 2013), paper 0581 (session 1)

Influence of the surroundings and mainly of the soil on MV cable systems

M Burceanu, B Hennuy, Q De Clerck, Laborelec, Linkebeek, Belgium, H Grandjean, ORES, Marche-En-Famenne, Belgium, M Van Den Berg, Sibelga, Bruxelles, Belgium, K Daems, P Leemans, Eandis, Melle, Belgium

CIRED 2013 (10-13 June 2013), paper 0651 (session 1)

Conductivity and quality of semi-conductive materials in MV cable accessories

N Quiévy, J Girboux, Q De Clerck, B Hennuy, Laborelec, Linkebeek, Belgium, P Leemans, Eandis, Melle, Belgium, M Van Den Berg, Sibelga, Brussels, Belgium, H Grandjean, ORES, Marche-En-Famenne, Belgium

CIRED 2013 (10-13 June 2013), paper 1341 (session 1)

Thermal behavior of connectors in joints

P Leemans, K Daems, Eandis, Melle, Belgium, H Grandjean, Ores, Aye, Belgium, M Van Den Berg, Sibelga, Brussels, Belgium, Q De Clerck, B Hennuy, Laborelec, Linkebeek, Belgium

CIRED 2013 (10-13 June 2013), paper 1377 (session 1)

Thermal behaviour of cables installed via directional drilling

K Daems, P Leemans, Eandis, Melle, Belgium, Q Declerck, M Burceanu, B Hennuy, Laborelec, Linkebeek, Belgium, H Grandjean, Ores, Aye, Belgium, M Van den Berg, Sibelga, Bruxelles, Belgium

CIRED 2013 (10-13 June 2013), paper 1411 (session 1)

PLC noise and impedance measurements on loads and in the distribution grid

R Jahn, S Uytterhoeven, D Lemmens, W Foubert, Laborelec, Linkebeek, Belgium

CIRED 2013 (10-13 June 2013), paper 1435 (session 2)

An advanced measurement method for power flow in medium voltage grids

S Uytterhoeven, S Doucement, M Dascotte, Laborelec, Brussels, Belgium

CIRED 2013 (10-13 June 2013), paper 0502 (session 3)

Living lab ‘Rotterdam tests electric driving' (focus on the monitoring of the impact on the electricity grid)

H Fidder, Stedin, Rotterdam, Netherlands, S Neuray, Eneco, Rotterdam, Netherlands, J Streng, City of Rotterdam, Rotterdam, Netherlands, R Jahn, M V Luming, Laborelec, Linkebeek, Belgium,

CIRED 2013 (10-13 June 2013), paper 1456 (session 5)

Modelling unsteady flow of a lean partially premixed flame on a dry low NOx combustion system

Salvatore Matarazzo, Hannes Laget, Evert Vanderhaegen and J.B.W. Kok

ASME Turbo Expo conference (June 2013), paper GT2013-94969

Water availability footprint of electricity production

Anne Prieur-Vernat, Jan Mertens

Life Cycle Management conference 2013

Accounting for impacts on water resources due to power production is needed to have a complete view of its environmental performance. As part of the periodically updated Life Cycle Assessment on the electricity produced by its power plants, GDF SUEZ has assessed the water availability footprint of its 2011 electricity production with the method developed by Boulay et al. in 2011. The purpose of this study is to analyze the impact associated to water use for electricity production, including both water used at the power plant and water used for the supply of fuels.

Data collected for the environmental reporting of all GDF SUEZ power plants have been used and the water use is detailed by source (surface or ground water) and by use within the power plant (cooling or industrial). The actual yearly average efficiency of each power plant as well as the location of the power plants is considered into the modeling. Around 400 production sites are included in the modeling, located in 36 different countries around the world. Background data have been taken from the Waterdatabase developed by Quantis International. The outcomes of the study show that background processes (supply chains of the fuel used and infrastructures to a lesser extent) have an important contribution to the water availability footprint: whereas they represent 30% of the total freshwater consumed per kWh produced, their contribution reaches 44% of the water availability footprint.

This study also demonstrate that impacts related to water use are highly sensitive to the electricity generation technology, but for a given technology, the results show an important variation of water availability footprint with the regional distribution: as an example, the specific fresh water consumption for the production of one kWh electricity in GDF SUEZ combined cycle gas turbines (CCGT) in Benelux & Germany is three times lower than for CCGT in North America, but their impact is two and a half time higher, due to local conditions. Those results are an interesting basis that can be used to define action plans at the Group level towards a better management of local water resources and of the water and energy nexus.

Detection and monitoring of shorted field windings in a large 4-pole generator rotor through vibration analysis: a case study

Ir. Koenraad De Bauw, Ir. Mirza Osmanovic, Ir. Kris Matthys

SIRM 2013 - 10th International Conference on Vibrations in Rotating Machines, Berlin, Germany, 25. – 27. February 2013

Laborelec is responsible for the follow-up of the vibration behaviour of a fleet of more than 100 shaft lines within the power generation division of GDF-Suez. Based on an experience of more than 20 years with continuous vibration monitoring in a close partnership with the power plants, Laborelec has been able to build up expertise in the analysis and solution of vibration problems on large turbomachinery. This paper describes a case study of increased vibrations of a 1000 MW generator with a 4-pole rotor in a nuclear power plant, due to shorted field windings in the rotor. Conventional detection methods for shorted field windings could not be easily applied for this unit. A comprehensive analysis of the vibration behaviour and an access to the complete history of the rotor’s operation and maintenance made it possible to identify the presence of shorted rotor field windings as the main cause of the increased vibrations. In order to maintain a reliable operation of the unit until the next opportunity to exchange the rotor, a detailed monitoring program was set up and measures were taken to reduce the vibrations on the unit and its peripheral equipment to acceptable levels. These measures included a field balancing correction, supported by a rotor dynamic analysis of the shaft train. The rotor will be exchanged at its next overhaul opportunity. The detailed analysis and monitoring enabled the owner to plan the rotor exchange well in advance and thus to reduce the related costs of the intervention.

Technical publications 2011

3 kHz Accelerated Growth of Water Trees in Medium Voltage Extruded Cables B. Hennuy, Q. De Clerck, Laborelec, Belgium 8th International Conference on Insulated Power Cables, Jicable, 19-23 June 2011, Versailles (France) A Power Line Communication measuring toolbox for the distribution grid R. Jahn, D. Lemmens, S. Uytterhoeven, Laborelec, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 1172 Applicability of methanol as new marker for paper degradation in power transformers A. Schaut, S. Autru, S. Eeckhoudt, Laborelec, Belgium IEEE Transactions on Dielectrics and Electrical Insulation, Volume 18, Issue 2, April 2011, pages 533 – 540 Automated Equilibrium Tension Lysimeters for Measuring Water Fluxes through a Layered, Volcanic Vadose Profile in New Zealand G.F. Barkle, Aqualinc Research Limited, New Zealand Th. Wöhling, R. Stenger, B. Moorhead, A. Wall, J. Clague, Lincoln Environmental Research, New Zealand J. Mertens, Laborelec, Belgium Vadose Zone Journal, May 2011 v. 10 no. 2, pages 747-759 Ecodesign in de tertiaire verlichting M. Vanden Bosch, Laborelec, Belgium Revue E (Société Royale Belge des Electriciens), 2011, Vol. 127, N° 2, pages 16-21 Failure analysis of a third stage gas turbine blade S. Barella, M. Boniardi, S. Cincera, P. Pellin, Politecnico di Milano (Italy) X. Degive, S. Gijbels, Laborelec, Belgium Engineering Failure Analysis, Volume 18, Issue 1, January 2011, pages 386–393 Harmonic behaviour of two commercial PV converters under distorted voltages M. De Witte, Y. Pankow, Laborelec, Belgium F. Colas, L2EP, France 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 1130 Impact of Variable Length Codes on the Interleaving Gain of Turbo Systems: The Concept of Bounded Spectrum X. Jaspar, Graduate Student Member, IEEE L. Vandendorpe, Fellow, IEEE IEEE Transactions on Communications, July 2011, Volume 59, Issue 7, pages 1796 – 1806 Incompatibility between MV Switchgear conform the international standards and their use in DNO's substations M. Arens, Y. Tits, Laborelec, Belgium J. Marginet, Eandis, Belgium A. François, Ores, Belgium M. van den Berg, Sibelga, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 0950 Life time estimation of SF6 MV switchgear according to on-site conditions on DNO's distribution networks Y. Tits, G. Delouvroy, Laborelec, Belgium J. Marginet, Eandis, Belgium A. François, Ores, Belgium M. van den Berg, Sibelga, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 0971 Microstructure of two centrifugal cast high speed steels for hot strip mills applications V. Vitry, F. Delaunois, Service de Métallurgie, Université de Mons, Belgium S. Nardone, Laborelec, Belgium J.-P. Breyer, M. Sinnaeve, Marichal Ketin, Belgium Materials and Design 34, Volume 32, Issue 1, January 2011, pages 372–378 Modelling of the heat transfer in a gas turbine liner combustor S. Matarazzo, H. Laget, Laborelec, Belgium 7th Mediterranean Combustion Symposium, 11-15 September 2011, Cagliari (Italy) New test results with 3khz accelerated growth of water trees in medium voltage cables B. Hennuy, Q. De Clerck, Laborelec, Belgium J. Marginet, P. Leemans, Eandis, Belgium D. Tenret, A. François, ORES, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 0679 Non-destructive DP analysis of kraft paper from shell-type power transformers P. Baird, H. Herman, G. Stevens, GnoSys UK Ltd, United Kingdom A. Schaut, Laborelec, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 1030 On-line monitoring and controlling emissions in amine post combustion carbon capture: A field test J. Mertens, M.-L. Thielens, Laborelec, Belgium J. Knudsen, J. Andersen, DONG Energy, Denmark International Journal of Greenhouse Gas Control, Volume 6, January 2012, Pages 2–11 The use of smart meters to improve customer load models F. Provoost, Alliander, the Netherlands M. Van Lumig, Laborelec, Belgium 21st International Conference on Electricity Distribution, CIRED 2011, 6-9-June 2011, Frankfurt (Germany), Paper 0799 ...