重油催化裂化装置汽提段及汽提工艺研究进展

重油催化裂化装置沉降器内汽提段的作用越来越受到重视，因为高效的汽提段可以降低焦炭的产率。国内外对汽提段的挡板型式、挡板倾角、裙板结构、蒸汽喷嘴分布等进行了改进，设计了预汽提及多段汽提，增加水蒸气和催化剂的接触面积。考察了汽提温度、时间、水蒸气量等汽提工艺条件对汽提效率的影响，认为汽提段存在重油液相分的化学反应，应对重油催化裂化汽提段结构和汽提工艺进行优化，以提高汽提效率，减少装置结焦。

Development of the Stripper and the Stripping Techniques of RFCC Units

The performances of RFCCU stripers became more and more concerned because a stripper with high efficiency could reduce the coke yield of RFCC process. So, much modification has been made to the baffle, the baffle obliquity, the baffle skirts as well as the steam nozzle distribution domestically and abroad. New pre-stripping and multi-stage stripping have been adapted so as to intensify the contact between catalyst and steam. Some literatures have investigated the effects of operation conditions such as temperature, resident time, stripping steam flux on the stripping efficiency. They concluded that optimization should be made to the structure and the operation conditions of strippers so as to raise the stripping efficiency and reduce the coke yield because of the existence of chemical reactions of liquid heavy fractions within the strippers.