The Experts below are selected from a list of 254364 Experts worldwide ranked by ideXlab platform
V Goetz - One of the best experts on this subject based on the ideXlab platform.
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definition test and simulation of a thermochemical Storage Process adapted to solar thermal systems
Solar Energy, 2006Co-Authors: H Lahmidi, Sylvain Mauran, V GoetzAbstract:Abstract The increase in the use of solar energy closely depends on the development of efficient Storage Processes. Solid–gas sorption Processes are a promising option as they offer a high Storage capacity and their specific working mode. In this paper, the integration of a sorption Process based on the use of bromide strontium as the reactant and water as the refrigerant fluid is investigated. Combined with flat plate solar collectors and direct floor heating and cooling, the system makes it possible to provide a heating and a cooling Storage function. Experimental tests have been conducted in the temperature ranges used in the solar heating and cooling systems. A simple model is proposed which allows an estimation of the performances in line with the heat and mass transfer characteristics of the reactive solid.
Jiri Jaromir Klemes - One of the best experts on this subject based on the ideXlab platform.
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life cycle analysis of a solar thermal system with thermochemical Storage Process
Renewable Energy, 2006Co-Authors: Nur Aini Masruroh, Bo Li, Jiri Jaromir KlemesAbstract:Solar energy itself is generally considered as environmentally friendly, nevertheless it is still important to take into consideration the environmental impacts caused by production of thousands of solar thermal systems. In this work the standard LCA methodology has been extended to analyse the total environmental impacts of a new more efficient solar thermal system SOLARSTORE during its whole life cycle. This system is being developed by a 5th Framework EC project. The LCA results show that to produce 1GJ energy with SOLARSTORE system will result in global warming potential of 6.3–10kg CO2, acidification potential of 46.6–70g SO2, eutrophication of 2.1–3.1g phosphate and photochemical oxidant of 0.99–1.5g C2H4. The raw material acquisition and components manufacturing Processes contribute 99% to the total environmental impacts. In comparison with traditional heating systems, SOLARSTORE system provides a considerably better solution for reduction of negative environmental impacts by using solar energy more efficiently.
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life cycle analysis of a solar thermal system with thermochemical Storage Process
Computer-aided chemical engineering, 2003Co-Authors: Nur Aini Masruroh, Bo Li, Jiri Jaromir KlemesAbstract:A new more efficient solar heating/cooling system has been developed for houses and buildings by an EU co-financed SOLASTORE (5FW ENERGIE) project with a consortium of partners from France, Spain, Portugal and the UK. It is targeting a considerable reduction of CO2 emission by improvement of the solar energy system efficiency and the extended utilization of the solar energy using reversible chemical reactions as energy Storage. Although solar energy is considered environmentally friendly, the whole life cycle of a solar energy production has to be evaluated. The production targets for the SOLARSTORE system are potentially thousands units. This makes it very important to explore the total environmental impacts caused during its whole life cycle. This work employs Life Cycle Analysis (LCA), an ISO 14040 based technique for evaluating the total environmental impacts associated with a product, to analyse the total environmental impacts of SOLARSTORE system during its whole life cycle. The standard LCA methodology has been extended and modified to cope successfully with this task. The LCA results show the total environmental impacts to achieve 1 GJ energy by using SOLARSTORE system: global warming potential ranging in 6.3–10 kg CO2, acidification potential in 46.6–70 g SO2, eutrophication in 2.1–3.1 g phosphate and photochemical oxidant in 0.99–1.5 g C2H4. The raw material acquisition Processes contribute 99% to the total environmental impacts. A LCA based comparison has been made analysing the total environmental impacts of a traditional solar heating system, a traditional fossil fuel heating system and SOLARSTORE system. It shows that SOLARSTORE provides a better solution for reduction of negative environmental impacts by using solar energy.
Jose Nilson Bezerra Campos - One of the best experts on this subject based on the ideXlab platform.
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modeling the yield evaporation spill in the reservoir Storage Process the regulation triangle diagram
Water Resources Management, 2010Co-Authors: Jose Nilson Bezerra CamposAbstract:From the dimensionless reservoir water budget equation, a graphical method to model the yield–spill–evaporation loss trade-off in the reservoir Storage Process was built. The reservoir inflows were transformed into three parts that sum to the total mean inflow for long-term operation: evaporation, spill and yield. A regulation triangle diagram (RTD) has been proposed to provide a better understanding of the reservoir Storage Process as a function of reservoir capacity, hydrological river regime, evaporation and reservoir morphology. The inflows were assumed to be serially uncorrelated and to originate from a Gamma probability distribution function. The diagrams were developed using the Monte Carlo method, while the graphics were developed for intermittent rivers with a coefficient of variation of annual inflows that ranges from 0.6 to 1.6. In the model, the reservoir is a single over-year system, and the values are referenced to the steady state conditions. Copyright The Author(s) 2010
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Modeling the Yield–Evaporation–Spill in the Reservoir Storage Process: The Regulation Triangle Diagram
Water Resources Management, 2010Co-Authors: Jose Nilson Bezerra CamposAbstract:From the dimensionless reservoir water budget equation, a graphical method to model the yield–spill–evaporation loss trade-off in the reservoir Storage Process was built. The reservoir inflows were transformed into three parts that sum to the total mean inflow for long-term operation: evaporation, spill and yield. A regulation triangle diagram (RTD) has been proposed to provide a better understanding of the reservoir Storage Process as a function of reservoir capacity, hydrological river regime, evaporation and reservoir morphology. The inflows were assumed to be serially uncorrelated and to originate from a Gamma probability distribution function. The diagrams were developed using the Monte Carlo method, while the graphics were developed for intermittent rivers with a coefficient of variation of annual inflows that ranges from 0.6 to 1.6. In the model, the reservoir is a single over-year system, and the values are referenced to the steady state conditions. Copyright The Author(s) 2010
Jean-françois Fourmigue - One of the best experts on this subject based on the ideXlab platform.
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A thermal energy Storage Process for large scale electric applications
Applied Thermal Engineering, 2010Co-Authors: Tristan Desrues, Jacques Ruer, Philippe Marty, Jean-françois FourmigueAbstract:A new type of thermal energy Storage Process for large scale electric applications is presented, based on a high temperature heat pump cycle which transforms electrical energy into thermal energy and stores it inside two large regenerators, followed by a thermal engine cycle which transforms the stored thermal energy back into electrical energy. The Storage principle is described, and its thermodynamic cycle is analyzed, leading to the theoretical efficiency of the Storage system. A numerical model is developed, and the results show the feasibility of the Process, even with sub-optimal parameters. Finally, key factors for improving the Process performances are identified.
D. Mangin - One of the best experts on this subject based on the ideXlab platform.
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Lithium bromide crystallization in water applied to an inter-seasonal heat Storage Process
Chemical Engineering Science, 2015Co-Authors: E. Lefebvre, L. Fan, E. Gagniere, S. Bennici, A. Auroux, D. ManginAbstract:This work is part of a larger study dedicated to an inter-seasonal heat Storage Process based on novel absorption pump operated in two half-cycles that uses LiBr/H2O as the absorbent/absorbate couple. The solar energy is stored during summer through desorption, and the heat is released during winter through absorption. A characteristic of the device is that crystallization occurs in the Storage tank as its temperature falls under 10 degrees C at the end of summer or in winter. Thus, information on the degree of hydration of the crystals at low temperature is required to optimize the Storage density. This paper aims to precisely determine the behavior of LiBr in terms of crystallization. In this study, solubility and metastable zone limit curves were assessed using an agitated and thermostated batch crystallizer. A video sensor was employed for assessment of the crystals morphology and thus, the hydrated crystalline forms present inside. The transition temperature between lithium bromide dihydrate and trihydrate was found to be equal to 3.0 degrees C. The dissolution and crystallization enthalpies were also calculated using the Van't Hoff plot, and results were found to be in good agreement with the literature data. (C) 2015 Elsevier Ltd. All rights reserved.
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THERMODYNAMIC STUDIES OF WATER ABSORPTION OF TERNARY SYSTEMS CONTAINING ZINC BROMIDE APPLIED IN SOLAR HEAT Storage Process
2013Co-Authors: E. Lefebvre, E. Gagniere, S. Bennici, D. Mangin, A. AurouxAbstract:Thermal solar energy Storage is an interesting way of reducing gas emissions. This Storage can be achieved using water vapour absorption-desorption in binary or ternary systems with a desiccant salt like lithium bromide, lithium chloride, zinc bromide, zinc chloride, etc. As illustrated in the figure below, in summer, solar energy dehydrates a concentrated solution of salt in the generator. The water vapour is condensed and stored in the water tank. The resulting more concentrated solution is stored in a semi crystallized form in a second tank. In winter, the previous condensed water is evaporated at low temperature, using geothermal source, and absorbed by the highly concentrated salt solution in the absorber, thus generating thermal energy. A previous successful work [1] was realised using lithium bromide as absorbent. In spite of its good thermal properties, its high price prevented it from use in the industrial Process. Therefore, i n order to design the most powerful system, it is important to determine its thermal behaviour compared to LiBr. In this work, dissolution enthalpies of various anhydrous salts (LiBr, LiCl, ZnCl2, ZnBr2, KOH, NaOH, KCHO2 and KC2H3O2) were determined. The experiments were performed by titration calorimetry at 25°C. The plot of cumulated enthalpies versus coefficient a= n_salt/n_solute allowed determining the dissolution and dilution enthalpies [2]. According to this study, zinc bromide presents the highest dissolution enthalpy. Nevertheless, literature data indicates a low activity coefficient of ZnBr2 in water which implies a weak ability of water absorption. Moreover, in the binary system ZnBr2/H2O, zinc hydroxide can be created and could gravitate in pipes. In order to improve the efficiency of a system comprising ZnBr2, this salt was associated to the previously cited anhydrous salt, in water or mixed solvents such as alcohol-water. Dissolution and dilution enthalpies at various ratios of salts of this new system were determined like previously. Furthermore, measurement of the vapour pressure above concentrated solution indicated the rate of water absorption and allowed determine the most suitable system for the Process. [1] K.E. NTsoukpoe, N. Le Pierrčs, L. Luo, Energy 37 (2012) 346-358 [2] M.H. Hamedi, B. Laurent, J-P.E. Grolier, Thermochim. Acta 445 (2006) 70-74
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Study of absorption couples used in solar heat Storage Process
2013Co-Authors: E. Lefebvre, E. Gagniere, S. Bennici, D. Mangin, A. AurouxAbstract:Thermal solar energy Storage is an interesting way of reducing gas emissions. This Storage can be achieved using water vapour absorption-desorption in a binary or ternary system with a desiccant salt-like lithium bromide, lithium chloride, calcium chloride, etc. As illustrated in the figure below, in summer, solar energy dehydrates a concentrated solution of salt in the generator. The water vapour is condensed and stored in the water tank. The resulting more concentrated solution is stored in a semi crystallized form in a second tank. In winter, the previous condensed water is evaporated at low temperature, using geothermal source, and absorbed by the highly concentrated salt solution in the absorber, thus generating thermal energy. Therefore, in order to design the most adaptable system for this Process, it is important to determine its thermal behaviour. In this work, dissolution and dilution enthalpies and solubilities were studied for five anhydrous salts (lithium chloride, lithium bromide, zinc bromide, zinc chloride and sodium thiocyanate) by titration calorimetry. Experiments were carried out at different temperatures from 25°C to 40°C. On one hand, the plot of cumulated enthalpy versus coefficient ą= n_salt/n_solute allows determining the dissolution and dilution enthalpies. One the other hand, these experiments allow to calculate the salt solubility and its kinetics for each temperature. The results have been compared to theoretical data. Moreover, salt hydration characteristics were studied. Indeed, the concentrated solution is crystallized in the tank to increase the Storage density and reduce the Storage tank size. Therefore, the salt should crystallize in anhydrous or at least in monohydrated form. The five anhydrous salts were hydrated at room temperature. They were analysed using thermogravimetry (TG) and differential scanning calorimetry (DSC) to determine the transition temperature of the hydrated form and its corresponding dehydration enthalpy.
