Research on HLCO entering the secondary riser of FDFCC unit to improve light aromatics production

Abstract In the context of prolific chemical raw materials, the flexible dual-riser fluid catalytic cracking (FDFCC) was put forward to increase the yield of light aromatics, in which hydrofining light cycle oil (HLCO) was processed in the second riser under high temperature. The process not only meets the increasing demand for aromatics, but also solves the problem of high aromatics content (more than 50 wt%) of FCC gasoline, which is difficult to meet increasingly stringent gasoline standards. The results of the pilot experiment showed that the optimization reaction temperature of the secondary riser of the FDFCC unit was 575 °C, and the content of aromatics in cracked gasoline reached 78 wt% or more. It should be noted that light cycle oil (LCO) should be subjected to deep hydrogenation from the perspective of increasing aromatics production.