【摘要】 对垂直立管中催化剂的流动性能进行了实验研究,测定了各种操作条件下立管中的轴向压力分布、催化剂循环速率以及附加吹气的影响. 实验结果表明,立管中的气固流动存在分别处于负压差下移下流区的“脱气段”和处于正压差下移下流区的“持气段”两种流动状态;下料阀开度对固体循环流率有明显的约束作用,且使“持气段”总压降增加较“脱气段”更为明显;对立管引入附加吹气有明显的增压作用,并使立管的压力分布有较大的改变. 根据实验结果及分析,对垂直立管的管形设计和催化剂在垂直立管中的密相输送提出了分析与建议.更多还原

【Abstract】 Experimental study was conducted on flow characteristics of catalyst in a standpipe with f108 mm4 mm and height of 10 m. The axial profile of pressure and circulating rate of catalyst in the standpipe and the influence of auxiliary air on them were measured. The experimental results show that the gas-solid flow in the standpipe is comprised of both flow status of stripping gas at the down move-flow region with negative pressure gradient and holding gas at the down move-flow region with positive pressure gradient. The restrictive effect of the open-extent of discharge valve on solid circulating rate is obvious, and the increase of overall pressure drop in the holding gas section is more notable than that in the stripping gas section. Auxiliary air to the standpipe with suitable air volume and at appropriate entry position is possessed of marked function to increase pressure, and will change the profile of pressure in the standpipe. Based on the experimental results and analysis, the idea and principle about design of standpipe shape and dense-phase transportation of catalyst in the standpipe were presented.更多还原