摘要:
According to this invention, there is provided a process and apparatus for catalytic cracking of various petroleum based heavy feed stocks in the presence of solid zeolite catalyst and high pore size acidic components for selective bottom cracking and mixtures thereof, in multiple riser type continuously circulating fluidized bed reactors operated at different severities to produce high yield of middle distillates, in the range of 50–65 wt % of fresh feed.