The Experts below are selected from a list of 21690 Experts worldwide ranked by ideXlab platform
Maciej Cholewinski - One of the best experts on this subject based on the ideXlab platform.
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modelling of a novel power generating cycle for the utilization of the cold exergy of Liquid Natural Gas with the adjustable parameters of working fluid
Energy Conversion and Management, 2019Co-Authors: łukasz Tomkow, Maciej CholewinskiAbstract:Abstract Utilization of the cold exergy of reGasified Liquid Natural Gas (LNG) improves the overall efficiency of the product chain by regaining the part of energy used to liquefy Natural Gas (NG). The application of a standard organic Rankine cycle in the case of high-pressure LNG (complying with the requirements of the Gas delivery networks after reGasification) leads to a comparatively low power generation and a large loss of exergy. In this paper we proposed a novel multi-stage power-generating cycle using a binary working fluid. By the separation of the ethane-krypton mixture into several streams with different component ratios and mass flows it was possible to adjust the process parameters and increase the net power that can be produced per unit of destroyed exergy. Furthermore, the proper selection of parameters allowed heat capacity to be increased at any temperature region in the heat exchanger, and thus increase exergy efficiency. Factors affecting the thermodynamic behavior of the system were presented and analyzed with numerical simulations. A significant increase of total exergetic efficiency (from 10% to 19.3%) was observed when compared with previously reported results for similar operating conditions. A net power of more than 15.4 kWh/t of reGasified NG at network pressure (8.5 MPa) was obtained.
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improvement of the lng Liquid Natural Gas reGasification efficiency by utilizing the cold exergy with a coupled absorption orc organic rankine cycle
Energy, 2015Co-Authors: łukasz Tomkow, Maciej CholewinskiAbstract:Abstract ReGasification is the process of evaporating and compressing LNG (Liquid Natural Gas) so that the product meets the parameters of a local distribution network. During this process large amounts of potentially useful exergy are destroyed. There were several proposals of using this potential in practice. In this paper the methods for electric energy production using cold exergy from a LNG stream are investigated. The new improvement is proposed for an absorption power cycle by coupling it with an organic Rankine cycle. The new components for working fluid are evaluated. The proposed solution is compared to existing ones and analyzed using a computer model. A significant increase of exergetic efficiency and power output is observed when compared to previous solutions.
Tiancheng Ouyang - One of the best experts on this subject based on the ideXlab platform.
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design and optimization of combined Gasoline vapor recovery cascade power and rectisol wash for Liquid Natural Gas cold energy utilization
Energy Conversion and Management, 2020Co-Authors: Tiancheng Ouyang, Zixiang Su, Feng Wang, Jiawei Li, Haozhong HuangAbstract:Abstract The worldwide energy crisis and environmental pollution have led to an enormous demand for Liquid Natural Gas. The recovery and application of cold energy released from the Liquid Natural Gas vaporization process can play a significant role in solving these issues. In this study, a new configuration is proposed to realize the cascade utilization of cold energy, which includes five subsystems: Gasoline vapor recovery, cascade Rankine power generation, Rectisol wash, air conditioning and liquefied air energy storage. Each subsystem is validated by the published literature of experiment and simulation, and parameters that are critical to the system are studied in depth. The genetic algorithm is then used to obtain the maximum net output power, using the working fluid composition, mass flow and fraction as optimization variables. As a result, the recovery rate of oil-Gas is 95%, which meets environmental regulations for vapor recovery. When a binary zeotropic mixture (fluoromethane/carbon dioxide, 0.2247/0.7753) is selected in an actual case, the specific work and exergy efficiency of power generation are 135.16 kJ/kg and 31.57%, respectively, and 2639 kg/h of raw coal-Gas can be purified to remove carbon dioxide. Under the coordination of liquefied air energy storage system coupled with an allocation algorithm, the demands and supplies of electricity and air conditioning have been matched. Therefore, the cascade utilization model provides a novel idea for cold energy recovery in Natural Gas stations.
Zhang Xin-rong - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic analysis of a novel pumped thermal energy storage system utilizing ambient thermal energy and LNG cold energy
ENERGY CONVERSION AND MANAGEMENT, 2017Co-Authors: Wang Guan-bang, Zhang Xin-rongAbstract:Pumped thermal energy storage (PTES) has become a hot topic on large scale energy storage technology because of the independence on geological conditions and fossil fuels. However, few of the PTES systems have higher round trip efficiencies compared with that of pumped hydro storage except for systems utilizing external heat sources. Furthermore, the used external heat sources are not available everywhere and much additional cost is required for the system integration. As an accessible and cheap heat source, ambient thermal energy is employed in the newly proposed PTES system. LNG (Liquid Natural Gas) cold energy is also used as the heat sink based on possible combination with the Natural Gas distribution system in the practical operation. The charge process is based on transcritical CO2 heat pump cycle, while cascade design of transcritical CO2 Rankine cycle and subcritical NH3 Rankine cycle is employed in the discharge process. A thermodynamic model is established for energy and exergy analysis as well as the system evaluation. The analysis and evaluation of the optimized baseline case obtained by Genetic Algorithm are then carried out. In addition, the sensitivity of system performance to different variable parameters is also analyzed. Based on the analysis of optimized baseline case, the round trip efficiency can reach 139%. If for 1 MW net power output, both of the mass flow rates of CO2 and NH3 are 7.4 kg/s with LNG mass flow rate of 14.8 kg/s. Because of much higher round trip efficiency compared with other large scale energy storage systems, the proposed system is promising for future development and applications. (C) 2017 Elsevier Ltd. All rights reserved.National Key Research and Development Program [2016YFD0400106]; Beijing Engineering Research Center of City HeatSCI(E)ARTICLE1248-126414
Haozhong Huang - One of the best experts on this subject based on the ideXlab platform.
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design and optimization of combined Gasoline vapor recovery cascade power and rectisol wash for Liquid Natural Gas cold energy utilization
Energy Conversion and Management, 2020Co-Authors: Tiancheng Ouyang, Zixiang Su, Feng Wang, Jiawei Li, Haozhong HuangAbstract:Abstract The worldwide energy crisis and environmental pollution have led to an enormous demand for Liquid Natural Gas. The recovery and application of cold energy released from the Liquid Natural Gas vaporization process can play a significant role in solving these issues. In this study, a new configuration is proposed to realize the cascade utilization of cold energy, which includes five subsystems: Gasoline vapor recovery, cascade Rankine power generation, Rectisol wash, air conditioning and liquefied air energy storage. Each subsystem is validated by the published literature of experiment and simulation, and parameters that are critical to the system are studied in depth. The genetic algorithm is then used to obtain the maximum net output power, using the working fluid composition, mass flow and fraction as optimization variables. As a result, the recovery rate of oil-Gas is 95%, which meets environmental regulations for vapor recovery. When a binary zeotropic mixture (fluoromethane/carbon dioxide, 0.2247/0.7753) is selected in an actual case, the specific work and exergy efficiency of power generation are 135.16 kJ/kg and 31.57%, respectively, and 2639 kg/h of raw coal-Gas can be purified to remove carbon dioxide. Under the coordination of liquefied air energy storage system coupled with an allocation algorithm, the demands and supplies of electricity and air conditioning have been matched. Therefore, the cascade utilization model provides a novel idea for cold energy recovery in Natural Gas stations.
Michel Feidt - One of the best experts on this subject based on the ideXlab platform.
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Process development and thermodynamic analysis of a novel power generation plant driven by geothermal energy with liquefied Natural Gas as its heat sink
Applied Thermal Engineering, 2018Co-Authors: Mirhadi S. Sadaghiani, M. H. Ahmadi, Fathollah Pourfayaz, Mehdi Mehrpooya, Michel FeidtAbstract:ORC and Kalina cycles can produce power from low-temperature heat sources. There is, also, a great potential in Liquid Natural Gas Gasification units to generate power derived from cold energy within these streams. This work proposes a new power generation plant to convert the trapped energies of geothermal hot water and Liquid Natural Gas streams to useful power. The combined power plant consists of 7 units, which each unit includes three discrete cycles of Kalina and two Organic Rankine power generation cycles to produce power from its heat sources. Geothermal hot water is supplied at 163 °C and pressure of 7 bar with a mass-flow of 39 kg/s from a geothermal well, and moreover, Natural Gas is supplied at −162 °C and pressure of 10 bar with a mass-flow of 8 kg/s to each unit of the power plant as a cold source. Energy and exergy analyses have been employed to evaluate the performance of the proposed plant. The energy analysis shows that each unit of the proposed plant could produce 1924 kW net power and the energy efficiency of each unit is 13.25%. On the other hand, the exergy analysis reveals that the exergy efficiency of each unit of the proposed plant is 26.13%, while each unit could recover 57% exergy of the LNG stream. Considering the results of the energy and exergy analyses along with sensitivity analysis, the system is amended to maximize the exergy efficiency, which after implementing modifications, the exergy efficiency of the system increases to 32.15%. Also, the net power output of each unit increases to 2485 kW after modifications.