放射性废物蒸汽重整垂直管内流场反应耦合数值模拟研究

Numerical Simulation Study on the Flow Field-reaction Coupled Characteristics of Radioactive Waste Steam Reforming Vertical Tubes

近年来,蒸汽重整技术在放射性有机废物处理方面得到了越来越多的关注。蒸汽重整的矿化还原反应炉主要采用流化床结构。其反应器内部的流场呈现多维耦合的特性,针对反应器内部多维耦合流场进行分析是优化反应器结构、确定反应参数的必要步骤。建立了包含气固两相流及树脂热解反应的耦合模型;并以小型蒸汽重整垂直管反应器为研究对象,对垂直管的表观气速及垂直管结构、垂直管内多维耦合流场进行了分析,确定了垂直管反应器的最佳结构参数及含固率分布。计算结果表明,扩径比为1∶2时,垂直管内的反应状态最佳。热态下固含率在提升管变径段内有所下降,但颗粒流型基本保持不变。

In recent years, steam reforming technology has received more and more attention in the treatment of radioactive organic waste. The steam reforming of the mineralized reduction reaction reactor is mainly with the fluid- ized bed structure. The flow field in the reactor is multi-dimensional coupling. The analysis of the multi dimensional coupled flow field in the reactor is a necessary step to optimize the structure of the reactor and to determine the re- action parameters. A coupled model of gas solid two phase flow and resin pyrolysis was established, and the vertical tube reactor was studied. The optimum structural parameters and the distribution of solid fraction were deter- mined. The calculation results show that the best expanding ratio is 1：2. In the hot model, solid content is lower in the expansion section, riser, but the particle flow pattern remained unchanged.