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.