This paper described the discovering process of some shortcomings of the conventional fluid catalytic cracking (FCC) process and the proposed two-stage riser (TSR) FCC process for decreasing dry gas and coke yields and increasing light oil yield, which has been successfully applied in 12 industrial units. Furthermore, the multifunctional two-stage riser (MFT) FCC process proposed on the basis of the TSR FCC process was described, which were carried out by the optimization of reaction conditions for fresh feedstock and cycle oil catalytic cracking, respectively, by the coupling of cycle oil cracking and light FCC naphtha upgrading processes in the second-stage riser, and the specially designed reactor for further reducing the olefin content of gasoline. The pilot test showed that it can further improve the product quality, increase the diesel yield, and enhance the conversion of heavy oil.

中文翻译：

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多功能两级立管流化床催化裂化工艺。

本文介绍了发现传统流化催化裂化（FCC）工艺和拟议的两级提升管（TSR）FCC工艺以减少干气和焦炭收率并提高轻油收率的不足之处的方法，该方法已成功应用于12个工业单位。此外，描述了基于TSR FCC工艺提出的多功能两级提升器（FCT）FCC工艺，其通过分别优化新鲜原料的反应条件和循环油催化裂化来进行，其通过以下步骤进行：在第二级提升管中进行循环油裂化和轻质FCC石脑油提质工艺，以及专门设计的反应器以进一步降低汽油的烯烃含量。中试表明，它可以进一步提高产品质量，提高柴油收率，