Process and apparatus for the maximization of middle distillates of FCC

摘要

Process and Parato to maximizing average desilados FCC are described a process apparatus for the maximization of middle distillates of FCC, said process comprising the cracking of a load 10 heavy hydrocarbons in the presence of catalyst and in the absence of hydrogen In an apparatus comprising added a first riser 21 operating in conditions of low severity.T = 460 - 520c, producing products 32 lighter separated in a separator 30, and a second riser 23 can severity, t = 550 - 620ec, said riser also acting as a catalyst cooler and producing products 42 separated in separator 40, the catalysts separated 30 and 40 being directed A rectifier 43 through a duct 44.And being injected into said riser 23 the currents 67e 68, HCO or its fractions lighter, in addition to the stream of light naphtha 64. The products 32 and 42 are respectively in the towers crumbled 60 E70. The catalyst covered with coke is regenerated in 50.The middle distillate obtained is of low aromaticity, naphtha hydrodessulfurization is high octane, and propene and ethene are obtained with higher proportions to those of conventional processes of FCC with low conversion.