Page 26 - Fluid Catalytic Cracking Handbook
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10 Fluid Catalytic Cracking Handbook
Figure 1-7. A two-stage cyclone system. (Courtesy of Bill Dougherty, BP Oil
Refinery, Marcus Hook, Pa.)
It is important to separate catalyst and vapors as soon as they enter
the reactor. Otherwise, the extended contact time of the vapors with
the catalyst in the reactor housing will allow for non-selective catalytic
recracking of some of the desirable products. The extended residence
time also promotes thermal cracking of the desirable products.
