太阳能驱动甲烷干重整热化学性能分析

Analysis of thermochemical performance of solar driven methane dry reforming

采用FLUENT软件耦合导热、对流、辐射以及反应动力学,建立了太阳能驱动甲烷干重整数值模型,研究了泡沫金属反应器内部甲烷干重整的热化学反应特性。计算得到了反应器内部温度场分布和各组分浓度分布,获得了进气流速和CH_(4)/CO_(2)摩尔分数比对反应物转化率、产物产率、积碳量和H_(2)/CO摩尔分数比的影响。结果表明:集中的太阳辐射在反应器前端形成一个高温核心区,重整反应在该区域最为活跃。反应物浓度沿反应器轴线方向迅速降低,产物浓度沿反应器轴线方向迅速上升。在一定范围内增大进气流速,能够提高H_(2)产率,虽然CH_(4)和CO_(2)转化率有所降低,但能有效的抑制积碳的生成,且能提高H_(2)/CO摩尔分数比。较低的CH_(4)/CO_(2)摩尔分数比能够提高CH_(4)转化率,且能有效的抑制积碳的生成,H_(2)产率在CH_(4)/CO_(2)摩尔分数比为2/3时达到最大值56%。

A numerical model of solar driven methane dry reforming was established to study the thermochemical reaction characteristics of methane dry reforming in metal foam reactor by using Fluent software combined with thermal conductivity,convection,radiation and reaction dynamics.The temperature field distribution and concentration distribution of each component in the reactor were shown,and the effects of inlet velocity and CH_(4)/CO_(2)ratio on reactant conversion,product yield,carbon deposition and H_(2)/CO ratio were obtained.The result shows that the concentrated solar radiation forms a high temperature core region at the front of the reactor,where the reforming reaction is most active.The reactant concentration decreases rapidly along the axis of the reactor,while the product concentration increases rapidly along the axis of the reactor.Increasing the inlet velocity within a certain range can improve the H_(2)yield.Although the CH_(4)and CO_(2)conversion rate decreases,it can effectively inhibit the carbon deposition and improve H_(2)/CO ratio.Lower CH_(4)/CO_(2)ratio can improve the CH_(4)conversion rate and effectively inhibit the carbon deposition.The maximum H_(2)yield reaches 56%when CH_(4)/CO_(2)ratio is 2/3.