Q & A > Question Details
In a two stage hydrocracker how can the selectivity for middle distillates can be improved at constant overall conversion?
14/07/2010 A: Prashant Parihar, BPCL, pariharprashant@bharatpetroleum.in
Manipulating the recycle cut point (RCP) in two stage hydrocracker is a good alternative for increasing selectivity for mid distillates. By increasing the recycle cut point, more distillate products can be recovered in the fractionator and less unconverted oil is sent to the second stage for further conversion. This results in reduced overall cracking to naphtha as well as a reduction in light ends as only unconverted part of feed sees second stage catalyst.
23/02/2010 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
There are catalysts formulated for gasoline operation, others for maximum diesel range product, and others for yielding both gasoline and diesel in an optimized manner. Other than using the best catalyst for the operating objective, I know of no other "handle".