催化裂解过程中空速和剂油比对液化气生成的影响

摘要

在小型固定流化床装置上,以减压蜡油为原料,采用含Y型分子筛和择形分子筛两种活性组分的催化剂,考察了进料空速和剂油比对液化气产率和组成的影响.结果表明:降低进料空速和增大剂油比都能够提高重油转化率和液化气产率,但两者对液化气组成的影响却截然不同；降低空速导致液化气丙烯含量提高,而增大剂油比却导致液化气丙烯含量降低；降低进料空速有利于催化剂中择形分子筛内的化学反应,增大剂油比则有利于催化剂中Y型分子筛内的化学反应.%The effect of catalyst to oil (C/O) ratio and weight hourly space velocity (WHSV) on the yield and compositions of LPG was investigated using a laboratory fixed-fluidized bed (FFB) unit, VGO feedstock, a catalyst containing zeolite Y and shape-selective zeolite. Test results show that with the decrease of WHSV and the increase of C/O ratio, both the LPG yield and heavy oil conversion enhance, but their effects on the compositions of LPG are distinct. With the decrease of WHSV the propylene content of LPG increases; contrarily, with the increase of C/O ratio, the propylene content of LPG decreases, the reason of which is discussed as well. It is found that the decrease of WHSV favors chemical reactions happened in the shape-selective zeolite, and with the increase of C/O ratio, reactions took place in zeolite Y are benefited.