供热方向及催化剂涂层厚度对微反应器中CH_4-H_2O重整反应的影响分析  

Effect Analysis of Heating Direction and Catalyst Coating Thickness on CH_4-H_2O Reforming in Microreactors

作　　者：曹军[1] 张莉[1] 徐宏[1] CAO Jun ZHANG Li XU Hong(School of Mechanical and Power Engineering ,East China University of Science and Technology, Shanghai 200221, China)

机构地区：[1]华东理工大学机械与动力工程学院,上海200237

出　　处：《石油学报（石油加工）》2017年第3期489-496,共8页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：中央高校基本科研业务费探索基金项目(WG1414044);中央高校基本科研业务费重点科研基地青年教师专项基金(WG1617011)资助

摘　　要：通过构建包含有动量、能量和质量传递以及甲烷水蒸气重整反应动力学方程的多物理场耦合数值模型,分析了催化剂壁面涂覆式微反应器CH_4-H_2O重整反应过程中逆流和顺流两种供热方式对反应通道中的温度场、浓度场以及CH_4转化率的影响,并计算了不同涂层厚度条件下的CH_4转化率及反应通道压降。结果表明,逆流供热方式下重整反应可以得到更高的CH_4转化率,但催化剂层的温度波动也比顺流供热更为明显。增大催化剂层厚度会提高CH_4的转化率,但同样会使反应通道的压降增大,然而,反应通道压降的增加值相对于重整的反应压力而言可忽略不计。此外,涂层厚度的增加还会造成催化剂层更为剧烈的温度变化。综合以上结论,从催化剂层均温性的角度考虑,涂覆式CH_4-H_2O重整微反应器对于供热方向和涂层厚度的选择需要在CH_4转化率和反应器的均温性之间做出平衡。A multi-physics-coupled numerical model, which contains the momentum, energy, mass transfer, as well as the chemical kinetic equations of CH4-H2O reforming in wall-coated microreactor has been carried out and analyzed in this paper. The effects of both counter-current flow and co-current flow of heat channel on the temperature and concentration distribution, as well as the CH4 conversion rate have been analyzed in detail; moreover, the CH4 conversion rate and pressure drop in reaction channel at different catalyst coating thicknesses were also calculated. It was found that a higher CH4 conversion rate can be obtained from the counter-current flow method for the reforming process; however, the temperature fluctuation in catalyst layer is also more significant. The conversion rate of CH4 increases with the increase of catalyst layer thickness, but an increase of pressure drop in the reaction channel also occurs. Compared with the reaction pressure, the increased pressure drop value is negligible. Furthermore, a more pronounced temperature fluctuation was also observed with higher catalyst layer thickness. In conclusion, the design of heating direction and catalyst layer thickness should be based on the careful trade-off between the CH4 conversion rate and temperature uniformity in catalyst layer for the wall-coated CH4-H2O microreactor.

关 键 词：涂覆式微反应器 CH4-H2O重整 供热方向 涂层厚度 数值分析 

分 类 号：TE65[石油与天然气工程—油气加工工程]