Abad Alberto, de Diego Luis F, García-Labiano Francisco, Izquierdo María T, Mendiara Teresa, Gayán Pilar, Adánez-Rubio Iñaki, Adánez Juan
Instituto de Carboquímica (ICB-CSIC), Miguel Luesma Castán 4, 50018 Zaragoza, Spain.
Energy Fuels. 2024 Oct 24;38(21):20681-20706. doi: 10.1021/acs.energyfuels.4c02880. eCollection 2024 Nov 7.
The unmixed combustion of biomass by chemical looping (Bio-CLC) has outstanding properties to produce energy by thermochemical conversion with CO capture at low economic and energetic costs as well as minimizing NOx emissions to the atmosphere. A detailed analysis of the experimental results during the biomass combustion in chemical looping combustion (CLC) units is useful to evaluate the Bio-CLC potential for future industrial up-scaling. This work compiles the results obtained during more than 500 h of combustion in the previous years at the Instituto de Carboquímica (ICB-CSIC). Different biomasses were burnt with several oxygen carriers in two singular CLC units. Critical key performance indicators, such as the CO capture rate and combustion efficiency, have been evaluated considering the combustion mode and the fluidization regime in the fuel reactor. Regarding the combustion mode, results by in situ gasification (G-CLC) vs chemical looping with oxygen uncoupling (CLOU) are compared. As for the fluidization regime, it was bubbling in a 0.5 kW CLC unit and circulating in a 50 kW CLC unit. A methodical comparison of the results allows us to understand the fundamentals of the processes and to evaluate the different behaviors observed in each case. The operating conditions having major effects on the Bio-CLC performance were identified, as well as the operating conditions necessary to optimize the CO capture and the combustion efficiency. In addition, other issues are evaluated, such as the fate of fuel-N in a CLC process, the presence of tar compounds in the CO stream, or the interaction of ash compounds with the oxygen carrier particles. Finally, possible future actions are discussed to improve the performance of the Bio-CLC process as well as the possible development paths of new oxygen carriers.
生物质化学链燃烧(Bio-CLC)的纯燃烧具有显著特性,能够以较低的经济和能源成本通过热化学转化生产能源并捕获二氧化碳,同时将氮氧化物排放到大气中的量降至最低。对化学链燃烧(CLC)装置中生物质燃烧实验结果进行详细分析,有助于评估Bio-CLC在未来工业扩大规模方面的潜力。这项工作汇总了过去几年在碳化学研究所(ICB-CSIC)超过500小时燃烧实验所获得的结果。在两个独特的CLC装置中,使用几种氧载体燃烧了不同的生物质。考虑到燃料反应器中的燃烧模式和流化状态,对关键性能指标,如二氧化碳捕获率和燃烧效率进行了评估。关于燃烧模式,比较了原位气化(G-CLC)与氧解耦化学链燃烧(CLOU)的结果。至于流化状态,在一个0.5千瓦的CLC装置中为鼓泡流化,在一个50千瓦的CLC装置中为循环流化。对结果进行系统比较,使我们能够理解这些过程的基本原理,并评估每种情况下观察到的不同行为。确定了对Bio-CLC性能有重大影响的操作条件,以及优化二氧化碳捕获和燃烧效率所需的操作条件。此外,还评估了其他问题,如CLC过程中燃料氮的归宿、一氧化碳流中焦油化合物的存在,或灰分化合物与氧载体颗粒的相互作用。最后,讨论了未来可能采取的行动,以提高Bio-CLC过程的性能以及新型氧载体可能的发展路径。