System Analysis on Supercritical CO_2 Power Cycle with Circulating Fluidized Bed Oxy-Coal Combustion
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摘要
Supercritical carbon dioxide(S-CO_2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO_2 generated from coal combustion still discharges into the atmosphere causing a series of environment problems. In this work, an 300 MWe S-CO_2 power cycle with circulating fluidized bed(CFB) oxy-coal combustion was established including air separation unit(ASU), CFB boiler, recuperator system and carbon dioxide compression and purification unit(CPU). Based on the material and energy conservation, the cycle efficiency of S-CO_2(620°C, 25 MPa) Brayton power cycle with CFB oxy-coal combustion is evaluated compared to the oxy-coal combustion steam Rankine cycle and S-CO_2 Brayton power cycle with the 31.65 kg/s coal supply. After that, the influence of several factors, e.g., exhaust flue gas temperature, split ratio in recuperator system and the oxygen supply on the cycle efficiency was investigated and analyzed. The results show that the net efficiency of S-CO_2 power cycle with CFB oxy-coal combustion(32.67%) is much higher than the steam Rankine cycle utilizing CFB with 17.5 Mpa, 540°C steam(27.3%), and 25 Mpa, 620°C steam(30.15%) under the same exhaust flue gas temperature. In addition, lower exhaust flue gas temperature and higher split ratio are preferred to achieve higher cycle efficiency. Lower oxygen supply can reduce the energy consumption of ASU and CPU, further increasing the system net efficiency. However, the energy losses of ASU and CPU are still very large in oxy-coal combustion and need to be improved in further work.
Supercritical carbon dioxide(S-CO_2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO_2 generated from coal combustion still discharges into the atmosphere causing a series of environment problems. In this work, an 300 MWe S-CO_2 power cycle with circulating fluidized bed(CFB) oxy-coal combustion was established including air separation unit(ASU), CFB boiler, recuperator system and carbon dioxide compression and purification unit(CPU). Based on the material and energy conservation, the cycle efficiency of S-CO_2(620°C, 25 MPa) Brayton power cycle with CFB oxy-coal combustion is evaluated compared to the oxy-coal combustion steam Rankine cycle and S-CO_2 Brayton power cycle with the 31.65 kg/s coal supply. After that, the influence of several factors, e.g., exhaust flue gas temperature, split ratio in recuperator system and the oxygen supply on the cycle efficiency was investigated and analyzed. The results show that the net efficiency of S-CO_2 power cycle with CFB oxy-coal combustion(32.67%) is much higher than the steam Rankine cycle utilizing CFB with 17.5 Mpa, 540°C steam(27.3%), and 25 Mpa, 620°C steam(30.15%) under the same exhaust flue gas temperature. In addition, lower exhaust flue gas temperature and higher split ratio are preferred to achieve higher cycle efficiency. Lower oxygen supply can reduce the energy consumption of ASU and CPU, further increasing the system net efficiency. However, the energy losses of ASU and CPU are still very large in oxy-coal combustion and need to be improved in further work.
Supercritical carbon dioxide(S-CO_2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO_2 generated from coal combustion still discharges into the atmosphere causing a series of environment problems. In this work, an 300 MWe S-CO_2 power cycle with circulating fluidized bed(CFB) oxy-coal combustion was established including air separation unit(ASU), CFB boiler, recuperator system and carbon dioxide compression and purification unit(CPU). Based on the material and energy conservation, the cycle efficiency of S-CO_2(620°C, 25 MPa) Brayton power cycle with CFB oxy-coal combustion is evaluated compared to the oxy-coal combustion steam Rankine cycle and S-CO_2 Brayton power cycle with the 31.65 kg/s coal supply. After that, the influence of several factors, e.g., exhaust flue gas temperature, split ratio in recuperator system and the oxygen supply on the cycle efficiency was investigated and analyzed. The results show that the net efficiency of S-CO_2 power cycle with CFB oxy-coal combustion(32.67%) is much higher than the steam Rankine cycle utilizing CFB with 17.5 Mpa, 540°C steam(27.3%), and 25 Mpa, 620°C steam(30.15%) under the same exhaust flue gas temperature. In addition, lower exhaust flue gas temperature and higher split ratio are preferred to achieve higher cycle efficiency. Lower oxygen supply can reduce the energy consumption of ASU and CPU, further increasing the system net efficiency. However, the energy losses of ASU and CPU are still very large in oxy-coal combustion and need to be improved in further work.
引文
[1]Moisseytsev A.,Sienicki J.J.,Investigation of alternative layouts for the supercritical carbon dioxide Brayton cycle for a sodium-cooled fast reactor.Nuclear Engineering and Design,2009,239(7):1362-1371.
[2]Ahn Y.,Bae S.J.,Kim M.,et al.,Review of supercritical CO2 power cycle technology and current status of research and development.Nuclear Engineering and Technology,2015,47(6):647-661.
[3]Sulzer G.,Verfahren zur erzeugung von arbeit aus warme(Method for producing work from heat).Swiss Patent269599,1948.
[4]Feher E.G.,The supercritical thermodynamic power cycle.Energy Conversion,1968,8(2):85-90.
[5]Angelino G.,Carbon dioxide condensation cycles for power production.Journal of Engineering for Power1968,90(3):287-295.
[6]Dostál V.,Driscoll M.J.,Hejzlar P.,A Supercritical carbon dioxide cycle for next generation nuclear reactors.Massachusetts Institute of Technology,2004.
[7]Neises T.,Turchi C.,A comparison of supercritical carbon dioxide power cycle configurations with an emphasis on CSP applications.Energy Procedia,2014,49:1187-1196.
[8]Padilla R.V.,Benito R.G.,Stein W.,An exergy analysis of recompression supercritical CO2 cycles with and without reheating.Energy Procedia,2015,69:1181-1191.
[9]Persichilli M.,Held T.,Hostler S.,et al.,Transforming waste heat to power through development of a CO2-based-power cycle.Electric Power Expo,2011:10-12.
[10]Wright S.,Davidson C.,Scammell W.,Thermo-economic analysis of four s CO2 waste heat recovery power systems//Fifth International SCO2 Symposium,San Antonio,TX,2016,pp.:28-31.
[11]Sánchez D.,Chacartegui R.,Jiménez-Espadafor F.,et al.,A new concept for high temperature fuel cell hybrid systems using supercritical carbon dioxide.Journal of Fuel Cell Science and Technology,2009,6(2):021306.
[12]Huang Y.,Wang J.,Zang J.,Liu G.,Research activities on supercritical carbon dioxide power conversion technology in China.In:ASME,editor.ASME turbo expo 2014:turbine technical conference and exposition,Dusseldorf.DOI:10.1115/GT2014-26049.
[13]Jeong W.S.,Lee J.I.,Jeong Y.H.,Potential improvements of supercritical recompression CO2 Brayton cycle by mixing other gases for power conversion system of a SFR.Nuclear Engineering and Design,2011,241(6):2128-2137.
[14]Dostal V.,Hejzlar P.,Driscoll M.J.,High-performance supercritical carbon dioxide cycle for next-generation nuclear reactors.Nuclear Technology,2006,154(3):265-282.
[15]Mecheri M.,Le Moullec Y.,Supercritical CO2 Brayton cycles for coal-fired power plants.Energy,2016,103:758-771.
[16]White C.,Shelton W.,Dennis R.,An assessment of supercritical CO2 power cycles integrated with generic heat sources//The 4th International SymposiumSupercritical CO2 Power Cycles.2014.
[17]Dyreby J.,Klein S.,Nellis G.,et al.,Design considerations for supercritical carbon dioxide Brayton cycles with recompression.Journal of Engineering for Gas Turbines and Power,2014,136(10):101701.
[18]Wang X.,Wang J.,Zhao P.,et al.,Thermodynamic comparison and optimization of supercritical CO2Brayton cycles with a bottoming transcritical CO2 cycle.Journal of Energy Engineering,2015,142(3):04015028.
[19]Wang X.,Wu Y.,Wang J.,Dai Y.,Xie D.,Thermoeconomic analysis of a recompression supercritical CO2cycle combined with a transcritical CO2 cycle.In:ASMEturbo expo 2015:turbine technical conference and exposition.Montreal:American Society of Mechanical Engineers;2015.DOI:10.1115/GT2015-42033.
[20]Wang X.,Dai Y.,Exergoeconomic analysis of utilizing the transcritical CO2 cycle and the ORC for a recompression supercritical CO2 cycle waste heat recovery:A comparative study.Applied Energy,2016,170:193-207.
[21]Kosowska-Golachowska M.,Thermal analysis and kinetics of coal during oxy-fuel combustion.Journal of Thermal Science,2017,26(4):355-361.
[22]Lockwood T.,Techno-economic analysis of PC versus CFB combustion technology.IEA Clean Coal Centre,Report CCC/226,London,UK,2013.
[23]Allam R.J.,Fetvedt J.E.,Forrest B.A.,et al.,The oxy-fuel,supercritical CO2 Allam Cycle:New cycle developments to produce even lower-cost electricity from fossil fuels without atmospheric emissions//ASME Turbo Expo 2014:Turbine Technical Conference and Exposition.American Society of Mechanical Engineers,2014:V03BT36A016-V03BT36A016.DOI:10.1115/GT2014-26952.
[24]Scaccabarozzi R.,Gatti M.,Martelli E.,Thermodynamic analysis and numerical optimization of the NET Power oxy-combustion cycle.Applied Energy,2016,178:505-526.
[25]Mc Clung A.,Brun K.,Delimont J.,Comparison of supercritical carbon dioxide cycles for oxy-combustion//ASME Turbo Expo 2015:Turbine Technical Conference and Exposition.American Society of Mechanical Engineers,2015:V009T36A006-V009T36A006.DOI:10.1115/GT2015-42523.
[26]Geng C.,Shao Y.,Zhong W.,et al.,Thermodynamic analysis of supercritical CO2 power cycle with fluidized bed coal combustion.Journal of Combustion,2018,2018.DOI:10.1155/2018/6963292.
[27]Jia L.,Tan Y.,Anthony E.J.,Emissions of SO2 and NOx during oxy-fuel CFB combustion tests in a minicirculating fluidized bed combustion reactor.Energy&Fuels,2009,24(2):910-915.
[28]Wall T.,Liu Y.,Bhattacharya S.,A scoping study on OxyCFB technology as an alternative carbon capture option for Australian black and brown coals.ANLEC R&D,Monash University,2012.
[29]Shelton W.W.,Weiland N.,White C.,et al.,Oxy-coal-fired circulating fluid bed combustion with a commercial utility-size supercritical CO2 power cycle//The 5th International Symposium-Supercritical CO2 Power Cycles,San Antonio,TX.2016.
[30]Xu J.,Sun E.,Li M.,et al.,Key issues and solution strategies for supercritical carbon dioxide coal fired power plant.Energy,2018,157:227-246.
[31]Xiong J.,Zhao H.,Chen M.,et al.,Simulation study of an800 MWe oxy-combustion pulverized-coal-fired power plant.Energy&Fuels,2011,25(5):2405-2415.
[32]Tsuo Y.P.,Gidaspow D.,Computation of flow patterns in circulating fluidized beds.AIChE Journal,1990,36(6):885-896.
[33]Hong J.,Field R.,Gazzino M.,et al.,Operating pressure dependence of the pressurized oxy-fuel combustion power cycle.Energy,2010,35(12):5391-5399.
[34]Zebian H.,Gazzino M.,Mitsos A.,Multi-variable optimization of pressurized oxy-coal combustion.Energy,2012,38(1):37-57.
[35]Mondal S.,De S.,CO2 based power cycle with multistage compression and intercooling for low temperature waste heat recovery.Energy,2015,90:1132-1143.
[36]Hong J.,Chaudhry G.,Brisson J.G.,et al.,Analysis of oxy-fuel combustion power cycle utilizing a pressurized coal combustor.Energy,2009,34(9):1332-1340.
[2]Ahn Y.,Bae S.J.,Kim M.,et al.,Review of supercritical CO2 power cycle technology and current status of research and development.Nuclear Engineering and Technology,2015,47(6):647-661.
[3]Sulzer G.,Verfahren zur erzeugung von arbeit aus warme(Method for producing work from heat).Swiss Patent269599,1948.
[4]Feher E.G.,The supercritical thermodynamic power cycle.Energy Conversion,1968,8(2):85-90.
[5]Angelino G.,Carbon dioxide condensation cycles for power production.Journal of Engineering for Power1968,90(3):287-295.
[6]Dostál V.,Driscoll M.J.,Hejzlar P.,A Supercritical carbon dioxide cycle for next generation nuclear reactors.Massachusetts Institute of Technology,2004.
[7]Neises T.,Turchi C.,A comparison of supercritical carbon dioxide power cycle configurations with an emphasis on CSP applications.Energy Procedia,2014,49:1187-1196.
[8]Padilla R.V.,Benito R.G.,Stein W.,An exergy analysis of recompression supercritical CO2 cycles with and without reheating.Energy Procedia,2015,69:1181-1191.
[9]Persichilli M.,Held T.,Hostler S.,et al.,Transforming waste heat to power through development of a CO2-based-power cycle.Electric Power Expo,2011:10-12.
[10]Wright S.,Davidson C.,Scammell W.,Thermo-economic analysis of four s CO2 waste heat recovery power systems//Fifth International SCO2 Symposium,San Antonio,TX,2016,pp.:28-31.
[11]Sánchez D.,Chacartegui R.,Jiménez-Espadafor F.,et al.,A new concept for high temperature fuel cell hybrid systems using supercritical carbon dioxide.Journal of Fuel Cell Science and Technology,2009,6(2):021306.
[12]Huang Y.,Wang J.,Zang J.,Liu G.,Research activities on supercritical carbon dioxide power conversion technology in China.In:ASME,editor.ASME turbo expo 2014:turbine technical conference and exposition,Dusseldorf.DOI:10.1115/GT2014-26049.
[13]Jeong W.S.,Lee J.I.,Jeong Y.H.,Potential improvements of supercritical recompression CO2 Brayton cycle by mixing other gases for power conversion system of a SFR.Nuclear Engineering and Design,2011,241(6):2128-2137.
[14]Dostal V.,Hejzlar P.,Driscoll M.J.,High-performance supercritical carbon dioxide cycle for next-generation nuclear reactors.Nuclear Technology,2006,154(3):265-282.
[15]Mecheri M.,Le Moullec Y.,Supercritical CO2 Brayton cycles for coal-fired power plants.Energy,2016,103:758-771.
[16]White C.,Shelton W.,Dennis R.,An assessment of supercritical CO2 power cycles integrated with generic heat sources//The 4th International SymposiumSupercritical CO2 Power Cycles.2014.
[17]Dyreby J.,Klein S.,Nellis G.,et al.,Design considerations for supercritical carbon dioxide Brayton cycles with recompression.Journal of Engineering for Gas Turbines and Power,2014,136(10):101701.
[18]Wang X.,Wang J.,Zhao P.,et al.,Thermodynamic comparison and optimization of supercritical CO2Brayton cycles with a bottoming transcritical CO2 cycle.Journal of Energy Engineering,2015,142(3):04015028.
[19]Wang X.,Wu Y.,Wang J.,Dai Y.,Xie D.,Thermoeconomic analysis of a recompression supercritical CO2cycle combined with a transcritical CO2 cycle.In:ASMEturbo expo 2015:turbine technical conference and exposition.Montreal:American Society of Mechanical Engineers;2015.DOI:10.1115/GT2015-42033.
[20]Wang X.,Dai Y.,Exergoeconomic analysis of utilizing the transcritical CO2 cycle and the ORC for a recompression supercritical CO2 cycle waste heat recovery:A comparative study.Applied Energy,2016,170:193-207.
[21]Kosowska-Golachowska M.,Thermal analysis and kinetics of coal during oxy-fuel combustion.Journal of Thermal Science,2017,26(4):355-361.
[22]Lockwood T.,Techno-economic analysis of PC versus CFB combustion technology.IEA Clean Coal Centre,Report CCC/226,London,UK,2013.
[23]Allam R.J.,Fetvedt J.E.,Forrest B.A.,et al.,The oxy-fuel,supercritical CO2 Allam Cycle:New cycle developments to produce even lower-cost electricity from fossil fuels without atmospheric emissions//ASME Turbo Expo 2014:Turbine Technical Conference and Exposition.American Society of Mechanical Engineers,2014:V03BT36A016-V03BT36A016.DOI:10.1115/GT2014-26952.
[24]Scaccabarozzi R.,Gatti M.,Martelli E.,Thermodynamic analysis and numerical optimization of the NET Power oxy-combustion cycle.Applied Energy,2016,178:505-526.
[25]Mc Clung A.,Brun K.,Delimont J.,Comparison of supercritical carbon dioxide cycles for oxy-combustion//ASME Turbo Expo 2015:Turbine Technical Conference and Exposition.American Society of Mechanical Engineers,2015:V009T36A006-V009T36A006.DOI:10.1115/GT2015-42523.
[26]Geng C.,Shao Y.,Zhong W.,et al.,Thermodynamic analysis of supercritical CO2 power cycle with fluidized bed coal combustion.Journal of Combustion,2018,2018.DOI:10.1155/2018/6963292.
[27]Jia L.,Tan Y.,Anthony E.J.,Emissions of SO2 and NOx during oxy-fuel CFB combustion tests in a minicirculating fluidized bed combustion reactor.Energy&Fuels,2009,24(2):910-915.
[28]Wall T.,Liu Y.,Bhattacharya S.,A scoping study on OxyCFB technology as an alternative carbon capture option for Australian black and brown coals.ANLEC R&D,Monash University,2012.
[29]Shelton W.W.,Weiland N.,White C.,et al.,Oxy-coal-fired circulating fluid bed combustion with a commercial utility-size supercritical CO2 power cycle//The 5th International Symposium-Supercritical CO2 Power Cycles,San Antonio,TX.2016.
[30]Xu J.,Sun E.,Li M.,et al.,Key issues and solution strategies for supercritical carbon dioxide coal fired power plant.Energy,2018,157:227-246.
[31]Xiong J.,Zhao H.,Chen M.,et al.,Simulation study of an800 MWe oxy-combustion pulverized-coal-fired power plant.Energy&Fuels,2011,25(5):2405-2415.
[32]Tsuo Y.P.,Gidaspow D.,Computation of flow patterns in circulating fluidized beds.AIChE Journal,1990,36(6):885-896.
[33]Hong J.,Field R.,Gazzino M.,et al.,Operating pressure dependence of the pressurized oxy-fuel combustion power cycle.Energy,2010,35(12):5391-5399.
[34]Zebian H.,Gazzino M.,Mitsos A.,Multi-variable optimization of pressurized oxy-coal combustion.Energy,2012,38(1):37-57.
[35]Mondal S.,De S.,CO2 based power cycle with multistage compression and intercooling for low temperature waste heat recovery.Energy,2015,90:1132-1143.
[36]Hong J.,Chaudhry G.,Brisson J.G.,et al.,Analysis of oxy-fuel combustion power cycle utilizing a pressurized coal combustor.Energy,2009,34(9):1332-1340.