油剂逆流接触FCC提升管进料段内喷嘴射流浓度的分布

Distribution of Feed Jet Concentration in Catalyst-Feed Countercurrent Contacting Injection Zone of a FCC Riser

通过一套大型冷模实验装置,考察了油剂逆流接触FCC提升管进料段内喷嘴射流在提升管不同轴向位置截面的浓度分布。针对前人采用脉冲示踪技术计算射流浓度时未考虑颗粒相的体积问题,进行理论分析,修正并提出了新的浓度分布计算表达式,并对比考察了修正后的效果。实验结果表明,修正后的表达式提高了射流浓度计算的准确度,减小了计算误差,采用油剂逆流接触新型结构,可使喷嘴射流相对浓度分布在油剂接触区内更均匀。

The radial distribution of feed jet concentration was studied in a large-scale cold model FCC riser, where the feed jets contacted counter-currently with particle flow from riser bottom in the feedstock injection zone. When pulse tracer technique was used to measure feed jet concentration, the particle volume was not considered in the calculating expressions of previous studies. Therefore, the discrepancy between particle volume considered and unconsidered was analysed, and a new expression was proposed. The experimental results show that the revised calculation expression can improve calculation accuracy and reduce errors. Moreover, the injection structure of catalyst-feed countercurrent contacting is better in realizing more uniform distribution of feed jet concentration in the feedstock injection zone.