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E Dick - One of the best experts on this subject based on the ideXlab platform.
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technological and economical analysis of water recovery in steam Injected Gas turbines
Applied Thermal Engineering, 2001Co-Authors: M De Paepe, E DickAbstract:Steam Injected Gas turbines are an interesting technology for co-generation applications. In these Gas turbines the heat of the exhaust Gases is used to produce steam. This steam is Injected in the combustion chamber, resulting in a high specific power and a high thermal efficiency. A major disadvantage of steam Injected Gas turbines is the large water consumption. Placing a condenser in the cycle makes it possible to recover all the Injected steam. An analysis is made of different types of condensers. Condensers based on finned tubes and direct-contact-condensers are considered. The dimensions of the condensers are determined for existing steam Injected Gas turbines. Furthermore, the investment costs and the exploitation costs for each type are compared.
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cycle improvements to steam Injected Gas turbines
International Journal of Energy Research, 2000Co-Authors: M De Paepe, E DickAbstract:The efficiency and specific power of the steam Injected Gas turbine is analysed by modelling the thermodynamic cycle. In this model special attention is paid to the blade cooling. The basic cycle as well as cycles with improvements such as intercooling, heat recovery by regenerator and blade cooling using steam are studied. The different cycles are compared with the combined cycle and the intercooled regenerative cycle. The conclusion is that the steam Injected cycles have high efficiency and specific power. Adding heat exchangers to the cycle is not beneficial. Using steam as coolant for the blades offers interesting perspectives. Copyright © 2000 John Wiley & Sons, Ltd.
Ali Akbar Alemrajabi - One of the best experts on this subject based on the ideXlab platform.
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exergy based performance analysis of a solid oxide fuel cell and steam Injected Gas turbine hybrid power system
International Journal of Hydrogen Energy, 2009Co-Authors: Sadegh Motahar, Ali Akbar AlemrajabiAbstract:This paper presents exergy analysis of a hybrid solid oxide fuel cell and Gas turbine (SOFC/ GT) system in comparison with retrofitted system with steam injection. It is proposed to use hot Gas turbine exhaust Gases heat in a heat recovery steam generator to produce steam and inject it into Gas turbine. Based on a steady-state model of the processes, exergy flow rates are calculated for all components and a detailed exergy analysis is performed. The components with the highest proportion of irreversibility in the hybrid systems are identified and compared. It is shown that steam injection decreases the wasted exergy from the system exhaust and boosts the exergetic efficiency by 12.11%. Also, 17.87% and 12.31% increase in exergy output and the thermal efficiency, respectively, is demonstrated. A parametric study is also performed for different values of compression pressure ratio, current density and pinch point temperature difference.
M De Paepe - One of the best experts on this subject based on the ideXlab platform.
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technological and economical analysis of water recovery in steam Injected Gas turbines
Applied Thermal Engineering, 2001Co-Authors: M De Paepe, E DickAbstract:Steam Injected Gas turbines are an interesting technology for co-generation applications. In these Gas turbines the heat of the exhaust Gases is used to produce steam. This steam is Injected in the combustion chamber, resulting in a high specific power and a high thermal efficiency. A major disadvantage of steam Injected Gas turbines is the large water consumption. Placing a condenser in the cycle makes it possible to recover all the Injected steam. An analysis is made of different types of condensers. Condensers based on finned tubes and direct-contact-condensers are considered. The dimensions of the condensers are determined for existing steam Injected Gas turbines. Furthermore, the investment costs and the exploitation costs for each type are compared.
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cycle improvements to steam Injected Gas turbines
International Journal of Energy Research, 2000Co-Authors: M De Paepe, E DickAbstract:The efficiency and specific power of the steam Injected Gas turbine is analysed by modelling the thermodynamic cycle. In this model special attention is paid to the blade cooling. The basic cycle as well as cycles with improvements such as intercooling, heat recovery by regenerator and blade cooling using steam are studied. The different cycles are compared with the combined cycle and the intercooled regenerative cycle. The conclusion is that the steam Injected cycles have high efficiency and specific power. Adding heat exchangers to the cycle is not beneficial. Using steam as coolant for the blades offers interesting perspectives. Copyright © 2000 John Wiley & Sons, Ltd.
Quoc P. Nguyen - One of the best experts on this subject based on the ideXlab platform.
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Low tension Gas flooding for secondary oil recovery in low-permeability, high-salinity reservoirs
Fuel, 2020Co-Authors: Alolika Das, Nhut M. Nguyen, Quoc P. NguyenAbstract:Abstract Low Tension Gas (LTG) flooding has been established as a successful tertiary oil recovery method for low-permeability carbonate reservoirs with high salinity and hard formation brine (~200,000 ppm and hardness 19,000 ppm). LTG flooding recovers oil using two integral mechanisms: ultra-low interfacial tension (IFT) between oil and water, and mobility control using in-situ foam generated by Injected Gas. In the present work, the scope of applicability of LTG flooding has been extended to secondary oil recovery under the same reservoir conditions. Secondary recovery using LTG flooding has been compared to conventional secondary recovery methods such as waterflooding. Oil recovery was observed to increase by 16% OOIP (Original Oil in Place) as compared to waterflooding, even in case of micellar flooding without Gas. On introducing mobility control during LTG flooding in the form of Injected Gas, the secondary oil recovery was observed to increase steadily up to 81% OOIP. Co-injecting Gas and surfactant also exhibited lower pressure drop than waterflood, thus underlining the importance and efficiency of mobility control using foam in secondary recovery. Gas injection strategy was improved in terms of Injected foam quality and onset of Gas injection. When Gas was Injected only during drive, ultimate oil recovery was reduced to 70% OOIP. Chemical injection strategy was also modified to test the impact of different in-situ salinity profiles on oil recovery.
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experimental study of injection strategy for low tension Gas flooding in low permeability high salinity carbonate reservoirs
Journal of Petroleum Science and Engineering, 2020Co-Authors: Alolika Das, Rouhi Farajzadeh, S Vincentbonnieu, Nhut Nguyen, Jeffrey G Southwick, S Khaburi, Al A Kindi, Quoc P. NguyenAbstract:Abstract Previous experimental studies have proven that Low-Tension-Gas (LTG) flooding can be a suitable enhanced oil recovery (EOR) method for low-permeability carbonate reservoirs with high salinity and hard formation brine. LTG flooding was observed to improve oil recovery by combining two effects: a reduction of the interfacial tension (IFT) between oil and water and mobility control through the formation of in-situ foam with an Injected Gas. However, the high cost of chemicals and/or the limited supply of Gas could make this process economically challenging. In this study, the primary goal was to reduce the amount of Injected Gas and surfactant to make the LTG process more economically feasible. A low-permeable ( 200,000 ppm and hardness 19,000 ppm) and temperature 69 °C was the target reservoir of this study. Effect of varying the concentration and pore volumes of the ultra-low IFT inducing surfactant slug Injected on oil recovery was studied. Nitrogen Gas was co-Injected during selected time periods throughout the entire surfactant injection in order to identify the significance of mobility control during the crucial phases of the LTG flooding. The coreflood results emphasized the significance of the injection of Gas, even at lower foam quality, for the maintenance of mobility control. Ultimate oil recovery of over 60% (residual oil post waterflood) was achieved, even after reducing the surfactant concentration by 75% and inducing a different in-situ salinity profile as compared to earlier studies. An innovative method for measuring surfactant adsorption using Liquid Chromatography and Mass Spectrometry (LC-MS) was developed, which could provide individual surfactant transport data for each of the three classes of surfactants used.
Noam Lior - One of the best experts on this subject based on the ideXlab platform.
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fuel allocation in a combined steam Injected Gas turbine and thermal seawater desalination system
Desalination, 2007Co-Authors: Yongqing Wang, Noam LiorAbstract:Fuel allocation in a combined steam-Injected Gas turbine (STIG) power generation and multi-effect thermal vapor compression (METVC) desalination system is studied, using seven methods: (1) Products Energy Method, (2) Products Exergy Method, (3) Power-Generation-Favored Method, (4) Heat-Production-Favored Method, (5) Basic Exergetic Cost Theory, (6) Functional Approach and (7) Splitting Factor Method. The latter three are thermoeconomics-based. Two sample cases are calculated. The methods and results are compared and discussed. The main conclusions are: it is important to carefully choose suitable methods to perform fuel allocation in a dual purpose desalination systems (here a combined STIG-METVC system) since different methods produce very different results; The results obtained from Methods (1) and (5) are unreasonable, and those from Methods (3) and (4) set the range within which the fuel allocation values must reside; Although thermoeconomic methodologies are considered to be the most rational for cost attribution of multi-product systems, false results could be reached if they are not suitably used; When sufficient information is unavailable for performing a thermoeconomic analysis, Method (2) can be taken as an approximation for fuel allocation, as well as for the distribution of fuel cost and combustion pollutant emission, between power and water in a STIG-METVC system. A recommended fuel allocation analysis procedure, based on this study and with some generality for other Gas-turbine power plant dual purpose thermal desalination systems, was outlined.
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performance analysis of combined humidified Gas turbine power generation and multi effect thermal vapor compression desalination systems part 1 the desalination unit and its combination with a steam Injected Gas turbine power system
Desalination, 2006Co-Authors: Yongqing Wang, Noam LiorAbstract:Abstract Humidified Gas turbines (HGT) have been identified as a promising way of producing power. The use of the steam-Injected Gas turbine (STIG) HGT cycle in a combined power and water desalination system was analyzed using energy and exergy performance criteria. A brief description and rationale of the background of HGT cycles and dual-purpose power and water systems is given. A thermal desalination unit was modeled and analyzed, and the results led to the selection of a multi-effect thermal vapor compression (METVC) unit for producing fresh water from seawater for both general use and humidification; then the performance of a STIG-based combined system was investigated. The analysis performed improved the understanding of the combined STIG power and water desalination process and of ways to improve and optimize it. Some specific conclusions are that: (1) a METVC desalination system is preferred to a multieffect evaporation one when the pressure of the motive steam is high enough, >∼3 bar, to run a steam jet ejector; (2) the steam injection rate in the STIG cycle has a strong effect on water and power production, offering good flexibility for design and operation; (3) higher pressure ratios and higher steam injection rates in the STIG cycle increase power generation, but decrease water production rates, and higher turbine inlet temperatures increased both power and water production; (4) a distinct water production gain can be obtained by recovering the stack Gas energy. The results indicate that such dual-purpose systems have good synergy, not only in fuel utilization, but also in operation and design flexibility.