摘要
传质是影响Ca(OH)_(2)/CaO热化学储热体系能量存储与释放的关键因素。本文考察了3种不同粒径(100、50、25μm)的CaO颗粒团簇在水合过程中的粒径、比表面积和孔隙率等尺度效应对传质效率的影响。在水合阶段,相比于水合反应前,不同粒径CaO颗粒团簇的粒径减小、比表面积增大、孔隙率降低,原先离散的CaO颗粒由于尺度效应更易聚集成团簇,阻碍了传质效率。与初始状态(t=10 min)相比,在反应后期(t=50 min),随着水合转化率的提高,3种不同粒径(100、50、25μm)的CaO颗粒其团聚作用力分别降低了27.01%、32.62%和42.61%,气体有效扩散率分别下降了14.24%、12.40%和11.09%,表观反应速率分别降低了78.99%、76.80%和76.20%。小粒径颗粒虽然更易聚集成团簇,但是由于小粒径颗粒具有较高的气体有效扩散率,加强了反应过程中的传质效率,因此表现出更高的水合能力。本文基于随机孔隙模型修正和量化了颗粒间团聚行为与气体有效扩散率对表观反应速率的协同影响。
Mass transfer is a key factor affecting the energy storage and release in Ca(OH)_(2)/CaO thermochemical storage system.This study investigated the effects of particle size,specific surface area and porosity of three different particle sizes(100,50,25μm)on mass transfer efficiency during hydration.During the hydration stage,Compared with the initial state,the particle size of CaO particle clusters with different particle sizes decreased,the specific surface area increased,and the porosity decreased.Due to the scale effect,the originally discrete CaO particles were more likely to aggregate into clusters,which hindered the mass transfer efficiency.Compared with the initial state(t=10 min),at the late stage(t=50 min),with the increase of hydration conversion rate,the agglomeration force of three CaO particles with different particle sizes(100,50,25μm)decreased by 27.01%,32.62%and 42.61%,the effective gas diffusivity decreased by 14.24%,12.40%and 11.09%,and the hydration reaction front velocity decreased by 78.99%,76.80%and 76.20%,respectively.Although the small particle size was more likely to aggregate into clusters,it had a high effective gas diffusivity,which enhanced the mass transfer efficiency in the reaction process and showed higher hydration capacity.Based on the modified random pore model,the synergistic effects of agglomeration behavior and effective gas diffusivity on the apparent reaction rate were quantified.
作者
顾屹仕
沈中杰
袁鼎轩
程玉祥
王景效
吕凤
万大阳
高永川
段乐章
刘海峰
GU Yishi;SHEN Zhongjie;YUAN Dingxuan;CHENG Yuxiang;WANG Jingxiao;LYU Feng;WAN Dayang;GAO Yongchuan;DUAN Yuezhang;LIU Haifeng(National Energy Coal Gasification Technology Research and Development Center,East China University of Science and Technology,Shanghai 200237,China;Shanghai Coal Gasification Engineering Technology Research Center,Shanghai 200237,China;RUICHEN PETROCHEMICAL,Shanghai 200233,China;Luoyang Ruichang Environment Engineering Co.Ltd,Luoyang 471003,Henan,China)
出处
《华东理工大学学报(自然科学版)》
北大核心
2025年第1期1-9,共9页
Journal of East China University of Science and Technology
基金
CO_(2)与成型吸附材料能质传递强化技术研究(2023YFB4104003-02)。
关键词
CAO
颗粒尺度
水合反应
气体有效扩散率
团聚行为
CaO
particle scale
hydration reaction
gas effective diffusion coefficient
agglomeration behavior
