Experimental study of two-stage riser FCC reactions

The concept of two-stage riser (TSR) fluid catalytic cracking (FCC) was tes ted in the laboratory. The goals were to improve product distribution and i ncrease product yield. A series of FCC runs was carried out in a pilot unit . At a similar conversion level, the results showed that the TSR FCC was be tter than the one-stage riser (OSR). The yields of gasoline and light oil i ncreased by 2-3% and 3-4%, respectively, and the gas decreased. The researc h and motor octane numbers of gasoline from the TSR FCC were higher than th ose from the OSR FCC by 2-3 and 1-2 units, respectively. Compared with the one-stage FCC, the gasoline produced from the TSR FCC contains less alkene and more iso-alkane. (C) 2001 Elsevier Science Ltd. All rights reserved.