气体流动条件下钴基催化剂固定床的传热

Heat Transfer in a Fixed Bed of Cobalt-based Catalyst with Flowing Gas

在气体流量4～8Nm3/h、气体分布器进口温度190～210℃、加热管壁温约240℃的条件下,对气体流动时活性组分呈蛋壳型分布的钴基催化剂固定床的传热进行了实验研究,建立了二维拟均相传热模型,利用正交配置法和Levenberg-Marquardt法对其求解,得到了钴基催化剂床层径向有效导热系数及壁给热系数的关联式,并将传热参数与由气体处于静态时固定床的有效导热系数计算而得的固定床传热参数值进行了比较,在气体入口温度范围内考察了其对固定床传热参数的影响.结果表明,实验所得传热参数与文献值的最大偏差绝对值均在15%以内.

An experimental study was conducted on the heat transfer in a fixed bed packed with cobalt-based catalyst when the gas was flowing in conditions of 240 ℃ wall temperature,190～210 ℃ gas distributor inlet temperature and 4～8 Nm3/h gas flow.A two-dimensional pseudo-homogeneous phase model was adapted to describe the heat transfer behavior in the bed.The radial effective thermal conductivity and the wall heat transfer coefficient were obtained by using the orthogonal collocation method and Levenberg-Marquardt method.The heat transfer parameters were correlated as a function of Reynolds number.The obtained correlations were applied to the comparison of heat transfer parameters based on the stagnant effective thermal conductivity.Meanwhile,the effect of gas inlet temperature range on the heat parameters was also investigated.The results showed that the maximum error between the transfer parameters obtained from experiment and the literature values was less than 15%.