沼气中CO_(2)的甲烷化反应及反应器研究  

Study on the methanation of CO_(2) in biogas and its reactor design

作　　者：章寒冰 叶吉超 胡鑫威 张磊 王立娜 王鸿 孙小毛 付鑫 刘长军[4] ZHANG Han-bing;YE Ji-chao;HU Xin-wei;ZHANG Lei;WANG Li-na;WANG Hong;SUN Xiao-mao;FU Xin;LIU Chang-jun(Lishui Power Supply Company,State Grid Zhejiang Electric Power Co.Ltd.,Lishui 323000,China;Jinyun Power Supply Company,State Grid Zhejiang Electric Power Co.Ltd.,Lishui 323000,China;Sichuan Energy Internet Research Institute,Tsinghua University,Chengdu 610042,China;School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]国网浙江省电力有限公司丽水供电公司,浙江丽水323000 [2]国网浙江省电力有限公司缙云县供电公司,浙江丽水321400 [3]清华四川能源互联网研究院,四川成都610042 [4]四川大学化学工程学院,四川成都610065

出　　处：《化学研究与应用》2023年第4期914-919,共6页Chemical Research and Application

基　　金：国网浙江省电力有限公司2021年科技项目(5211LS21N005)。

摘　　要：本文采用计算流体力学方法建立了以沼气为原料气的CO_(2)甲烷化反应器模型,通过多物理场耦合求解获得了不同反应条件下甲烷化反应器内的温度分布和反应速率等数据,考察了反应温度、压力、流速等对甲烷化反应的影响。研究结果表明,提高反应温度和压力有利于提高CO_(2)甲烷化反应速率和生产效率,但在相同装填量的催化剂床层CO_(2)的出口转化率降低。以Al_(2)O_(3)为载体的Ni催化剂,在床层直径小于25 mm时,恒壁温条件下床层内外温差为3.1℃。综合热力学和动力学两方面的影响,以沼气为原料的CO_(2)甲烷化反应温度应以300~400℃为宜。在300℃,1.0 MPa的反应条件下,反应停留时间大于257.6 s可达到高于98%的CO_(2)转化率。Fixed-bed methanation reactor models of different size were purposed.The temperature distribution and the reaction rate distribution inside each of the catalyst beds were simulated by simultaneous solving the coupled multiphysics of the fluid flow,heat transfer and mass transfer.The effects of the reaction temperature,inlet flowrate and outlet pressure on the conversion of CO_(2) in a biogas were studied.It is found that the elevation of the reaction temperature and pressure favors enhancing the methanation rate and increasing the productivity of the reactor.However,the CO_(2) conversion is lower at the outlet at higher reaction pressure for a given catalyst bed.For Ni/Al_(2)O_(3) catalyst,the maximum temperature difference in the cross section of the reactor is within 3.1℃for reactors with a diameter less than 25 mm.The optimal reaction temperature for the methanation of CO_(2) in a biogas is in the range of 300~400℃in order to achieve high conversion at relatively higher productivity.98%CO_(2) conversion can be achieved with a residence time of 257.6 s at 300℃and 1.0 MPa conditions.

关 键 词：甲烷化反应 反应器 CFD 多物理场 

分 类 号：TE644[石油与天然气工程—油气加工工程] TQ110[化学工程—无机化工]