为了获取更高的低碳烯烃收率，开发了双催化剂催化裂化技术。该技术采用反应并联、催化剂分区再生的技术手段，同时使用Y型催化剂和ZSM-5分子筛催化剂。反应部分采用双提升管工艺，重油与轻油分别匹配不同的催化剂和工艺条件在不同的提升管内进行反应。再生部分采用分区再生、烟气串联的两段再生技术，避免2种催化剂混合，同时保证轻油裂化所需的热量。中试试验结果表明，该技术可以显著提高催化裂化装置的低碳烯烃产率。

To obtain higher yield of low-carbon olefins,a double-catalyst fluid catalytic cracking process (DCFCC) is developed.This process adopts the technical means of parallel reaction and partition regeneration of catalyst,while using Y-type and ZSM-5 molecular sieve simultaneously.The reaction part of the process adopts dual riser reactors,and heavy oil and light oil are matched with different catalysts and process conditions to react in different riser.The regeneration part of the process adopts a two-stage regeneration technology including partition regeneration and flue gas series.This process avoids the mixing of two catalysts and ensures the heat required for light oil cracking.Pilot test results show that this process can significantly increase the yield of low-carbon olefins in FCC unit.