Calcium looping heat storage performance and mechanical property of CaO-based pellets under fluidization

• 作者: Zhangke Ma Yingjie Li Boyu Li Zeyan Wang Tao Wang Wentao Lei
• 来源期刊: 中国化学工程学报（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: Energy Science and Technology
• 页码范围: 170-180
• 页数: 11页
• 语种: 英文

摘要

The CaO-based pellets were fabricated using extrusion-spheronization method for calcium looping ther-mochemical heat storage under the fluidization.The effects of adhesive,biomass-based pore-forming agent,binder and particle size on the heat storage performance and mechanical property of the CaO-based pellets were investigated in a bubbling fluidized bed reactor.The addition of 2％ (mass)polyvinylpyrrolidone as an adhesive not only helps granulate,but also improves the heat storage capacity of the pellets.All biomass-templated CaO-based pellets display higher heat storage capacity than biomass-free pellets,indicating that the biomass-based pore-forming agent is beneficial for heat storage under the fluidization.Especially,bagasse-templated pellets show the highest heat storage conversion of 0.61 after 10 cycles.Moreover,Al2O3 as a binder for the pellets helps obtain high mechanical strength.The CaO-based pellets doped with 10％ (mass) bagasse and 5％ (mass) Al2O3 reach the highest heat storage density of 1621 kJ·kg-1 after 30 cycles and the highest crushing strength of 4.98 N.The microstructure of the bagasse-templated pellets appears more porous than that of biomass-free pellets.The bagasse-templated CaO-based pellets doped with Al2O3 seem promising for thermochemical heat storage under the fluidization,owing to the enhanced heat storage capacity,excellent mechanical strength,and simplic-ity of the synthesis procedure.