基于Ca-Cu Looping的燃烧后碳捕集系统的过程模拟和分析
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摘要
新发展的基于CaO/CaCO_3-CuO/Cu颗粒体系的钙-铜循环(Ca-Culooping)利用CuO与燃料的放热反应来提供CaCO_3煅烧所需的热量,有望降低碳捕集成本和能耗.通过组织颗粒的循环方式,可以获得3种钙-铜循环模式:碳酸化-煅烧/还原-氧化-碳酸化、碳酸化-氧化-煅烧/还原-碳酸化、碳酸化/氧化-煅烧/还原-碳酸化/氧化.本文利用流程模拟软件AspenPlus对3种钙-铜循环燃烧后碳捕集系统进行过程模拟、参数优化和分析,并与常规的钙循环系统进行比较.发现碳酸化-氧化-煅烧/还原-碳酸化循环的碳酸化转化率最高,达到81.44%;钙-铜循环中煅烧反应器运行在常压、820℃,钙循环中煅烧反应器运行在常压、840℃时,可实现完全转化;钙循环对燃料和空气的需求量均低于钙-铜循环;对于钙-铜循环,3种循环模式所需铜钙比(Cu/Ca摩尔比)为5.13～5.19,比值相近.分析结果显示,损最大处发生在煅烧反应器中,基于碳酸化-氧化-煅烧/还原-碳酸化的钙-铜循环系统的效率最高,可达65.04%,与常规钙循环系统相比,效率提高了约30%.
A novel Ca-Cu looping,based on CaO/CaCO_3-CuO/Cu bi-carriers,solves this problem in a subtle way by providing the heat released from the exothermic reaction of CuO with fuel to the endothermic reaction of CaCO_3 calcination,which is expected to lower the CO2 capture cost as well as the overall energy consumption. Typically, there are three kinds of solid cycle used for Ca-Cu looping :(1) carbonation-calcination/reductionoxidation-carbonation,(2)carbonation-oxidation-calcination/reduction-carbonation,and(3)carbonation/oxidationcalcination/reduction-carbonation/oxidation. In this work,we used Aspen Plus software to conduct process simulations of these three kinds of Ca-Cu looping,with a main focus on parameter optimization and exergy analysis. The simulation results showed that the second type of Ca–Cu looping had the highest carbonation conversion of up to 81.44%. In operation conditions of 0.1 MPa,820 ℃,complete conversion can be achieved in the calciner for CaCu looping,where asoperation conditions of 0.1 MPa,840 ℃ were needed for Ca-looping. Compared with Ca-Cu looping,the fuel and air requirements were both lower in Ca-looping,and a Cu/Ca molar ratio of 5.13—5.19 was necessary in Ca-Cu looping. Our exergy analysis results indicated that the maximum exergy destruction occurs in the calciner and the second type of Ca-Cu looping had the highest exergy efficiency of up to 65.04%,which was approximately 30% higher than that of the traditional Ca-looping.
A novel Ca-Cu looping,based on CaO/CaCO_3-CuO/Cu bi-carriers,solves this problem in a subtle way by providing the heat released from the exothermic reaction of CuO with fuel to the endothermic reaction of CaCO_3 calcination,which is expected to lower the CO2 capture cost as well as the overall energy consumption. Typically, there are three kinds of solid cycle used for Ca-Cu looping :(1) carbonation-calcination/reductionoxidation-carbonation,(2)carbonation-oxidation-calcination/reduction-carbonation,and(3)carbonation/oxidationcalcination/reduction-carbonation/oxidation. In this work,we used Aspen Plus software to conduct process simulations of these three kinds of Ca-Cu looping,with a main focus on parameter optimization and exergy analysis. The simulation results showed that the second type of Ca–Cu looping had the highest carbonation conversion of up to 81.44%. In operation conditions of 0.1 MPa,820 ℃,complete conversion can be achieved in the calciner for CaCu looping,where asoperation conditions of 0.1 MPa,840 ℃ were needed for Ca-looping. Compared with Ca-Cu looping,the fuel and air requirements were both lower in Ca-looping,and a Cu/Ca molar ratio of 5.13—5.19 was necessary in Ca-Cu looping. Our exergy analysis results indicated that the maximum exergy destruction occurs in the calciner and the second type of Ca-Cu looping had the highest exergy efficiency of up to 65.04%,which was approximately 30% higher than that of the traditional Ca-looping.
引文
[1]Blamey J,Anthony E J,Wang J,et al.The calcium looping cycle for large-scale CO2 capture[J].Progress in Energy and Combustion Science,2010,36(2):260-279.
[2]Dupont V,Ross A B,Knight E,et al.Production of hydrogen by unmixed steam reforming of methane[J].Chemical Engineering Science,2008,63(11):2966-2979.
[3]Shimizu T,Hirama T,Hosoda H,et al.A twin fluidbed reactor for removal of CO2 from combustion processes[J].Chemical Engineering Research&Design,1999,77(1):62-68.
[4]Fernandez J R,Abanades J C,Murillo R,et al.Conceptual design of a hydrogen production process from natural gas with CO2 capture using a Ca-Cu chemical loop[J].International Journal of Greenhouse Gas Control,2012,6:126-141.
[5]Kumar R V,Lyon R K,Cole J A.Unmixed reforming:a novel autothermal cyclic steam reforming process[C]//Advances in Hydrogen Energy.Boston:Springer,2002:31-45.
[6]Abanades J C,Murillo R,Fernandez J R,et al.New CO2 capture process for hydrogen production combining Ca and Cu chemical loops[J].Environmental Science&Technology,2010,44(17):6901-6904.
[7]Qin C L,Feng B,Yin J J,et al.Matching of kinetics of CaCO3 decomposition and CuO reduction with CH4 in Ca-Cu chemical looping[J].Chemical Engineering Journal,2015,262(1):665-675.
[8]Martinez I,Romano M C,Fernandez J R,et al.Process design of a hydrogen production plant from natural gas with CO2 capture based on a novel Ca/Cu chemical loop[J].Applied Energy,2014,114(2):192-208.
[9]Ozcan D C,Macchi A,Lu D Y,et al.Ca-Cu looping process for CO2 capture from a power plant and its comparison with Ca-looping,oxy-combustion and amine-based CO2 capture processes[J].International Journal of Greenhouse Gas Control,2015,43:198-212.
[10]Martinez I,Murillo R,Grasa G,et al.Design of a hydrogen production process for power generation based on a Ca-Cu chemical loop[J].Energy Procedia,2013,37(3):626-634.
[11]Qin C L,Yin J J,Liu W Q,et al.Behavior of CaO/CuO based composite in a combined calcium and copper chemical looping process[J].Industrial&Engineering Chemistry Research,2012,51(38):12274-12281.
[12]Martinez I,Grasa G,Murillo R,et al.Modelling the continuous calcination of CaCO3 in a Ca-looping system[J].Chemical Engineering Journal,2013,215:174-181.
[13]Abanades J C.The maximum capture efficiency of CO2using a carbonation/calcination cycle of CaO/CaCO3[J].Chemical Engineering Journal,2002,90(3):303-306.
[14]陈海平,王忠平,吴文浩,等.基于Aspen Plus的CCRs碳捕捉系统过程模拟[J].动力工程学报,2012,32(7):558-561.Chen Haiping,Wang Zhongping,Wu Wenhao,et al.Process simulation of the multiple cyclic CCRs system for CO2 capture based on Aspen Plus[J].Jourmal of Chinese Society of Power Engineering,2012,32(7):558-561(in Chinese).
[15]Forero C R,Gayan P,Garcia-Labiano F,et al.High temperature behaviour of a CuO/γ-Al2O3 oxygen carrier for chemical-looping combustion[J].International Journal of Greenhouse Gas Control,2011,5(4):659-667.
[16]Lasheras A,Strohle J,Galloy A,et al.Carbonate looping process simulation using a 1D fluidized bed model for the carbonator[J].International Journal of Greenhouse Gas Control,2011,5(4):686-693.
[17]Hawthorne C,Trossmann M,Cifre P G,et al.Simulation of the carbonate looping power cycle[J].Energy Procedia,2009,1(1):1387-1394.
[18]Charitos A,Hawthorne C,Bidwe A R,et al.Parametric investigation of the calcium looping process for CO2 capture in a 10 kWth dual fluidized bed[J].International Journal of Greenhouse Gas Control,2010,4(5):776-784.
[19]Garcia-Labiano F,de Diego L F,Adanez J,et al.Reduction and oxidation kinetics of a copper-based oxygen carrier prepared by impregnation for chemicallooping combustion[J].Industrial&Engineering Chemistry Research,2004,43(26):8168-8177.
[20]Xiong J,Zhao H B,Zheng C G.Exergy analysis of a600 MWe oxy-combustion pulverized-coal-fired power plant[J].Energy&Fuels,2011,25(8):3854-3864.
[2]Dupont V,Ross A B,Knight E,et al.Production of hydrogen by unmixed steam reforming of methane[J].Chemical Engineering Science,2008,63(11):2966-2979.
[3]Shimizu T,Hirama T,Hosoda H,et al.A twin fluidbed reactor for removal of CO2 from combustion processes[J].Chemical Engineering Research&Design,1999,77(1):62-68.
[4]Fernandez J R,Abanades J C,Murillo R,et al.Conceptual design of a hydrogen production process from natural gas with CO2 capture using a Ca-Cu chemical loop[J].International Journal of Greenhouse Gas Control,2012,6:126-141.
[5]Kumar R V,Lyon R K,Cole J A.Unmixed reforming:a novel autothermal cyclic steam reforming process[C]//Advances in Hydrogen Energy.Boston:Springer,2002:31-45.
[6]Abanades J C,Murillo R,Fernandez J R,et al.New CO2 capture process for hydrogen production combining Ca and Cu chemical loops[J].Environmental Science&Technology,2010,44(17):6901-6904.
[7]Qin C L,Feng B,Yin J J,et al.Matching of kinetics of CaCO3 decomposition and CuO reduction with CH4 in Ca-Cu chemical looping[J].Chemical Engineering Journal,2015,262(1):665-675.
[8]Martinez I,Romano M C,Fernandez J R,et al.Process design of a hydrogen production plant from natural gas with CO2 capture based on a novel Ca/Cu chemical loop[J].Applied Energy,2014,114(2):192-208.
[9]Ozcan D C,Macchi A,Lu D Y,et al.Ca-Cu looping process for CO2 capture from a power plant and its comparison with Ca-looping,oxy-combustion and amine-based CO2 capture processes[J].International Journal of Greenhouse Gas Control,2015,43:198-212.
[10]Martinez I,Murillo R,Grasa G,et al.Design of a hydrogen production process for power generation based on a Ca-Cu chemical loop[J].Energy Procedia,2013,37(3):626-634.
[11]Qin C L,Yin J J,Liu W Q,et al.Behavior of CaO/CuO based composite in a combined calcium and copper chemical looping process[J].Industrial&Engineering Chemistry Research,2012,51(38):12274-12281.
[12]Martinez I,Grasa G,Murillo R,et al.Modelling the continuous calcination of CaCO3 in a Ca-looping system[J].Chemical Engineering Journal,2013,215:174-181.
[13]Abanades J C.The maximum capture efficiency of CO2using a carbonation/calcination cycle of CaO/CaCO3[J].Chemical Engineering Journal,2002,90(3):303-306.
[14]陈海平,王忠平,吴文浩,等.基于Aspen Plus的CCRs碳捕捉系统过程模拟[J].动力工程学报,2012,32(7):558-561.Chen Haiping,Wang Zhongping,Wu Wenhao,et al.Process simulation of the multiple cyclic CCRs system for CO2 capture based on Aspen Plus[J].Jourmal of Chinese Society of Power Engineering,2012,32(7):558-561(in Chinese).
[15]Forero C R,Gayan P,Garcia-Labiano F,et al.High temperature behaviour of a CuO/γ-Al2O3 oxygen carrier for chemical-looping combustion[J].International Journal of Greenhouse Gas Control,2011,5(4):659-667.
[16]Lasheras A,Strohle J,Galloy A,et al.Carbonate looping process simulation using a 1D fluidized bed model for the carbonator[J].International Journal of Greenhouse Gas Control,2011,5(4):686-693.
[17]Hawthorne C,Trossmann M,Cifre P G,et al.Simulation of the carbonate looping power cycle[J].Energy Procedia,2009,1(1):1387-1394.
[18]Charitos A,Hawthorne C,Bidwe A R,et al.Parametric investigation of the calcium looping process for CO2 capture in a 10 kWth dual fluidized bed[J].International Journal of Greenhouse Gas Control,2010,4(5):776-784.
[19]Garcia-Labiano F,de Diego L F,Adanez J,et al.Reduction and oxidation kinetics of a copper-based oxygen carrier prepared by impregnation for chemicallooping combustion[J].Industrial&Engineering Chemistry Research,2004,43(26):8168-8177.
[20]Xiong J,Zhao H B,Zheng C G.Exergy analysis of a600 MWe oxy-combustion pulverized-coal-fired power plant[J].Energy&Fuels,2011,25(8):3854-3864.