Q & A > Question Details
Anyone suggest me about increasing Propylene production in FCC without affecting stripper dp. In our refinery 2 Reactors or working in poly Propylene unit (PPU) for poly Propylene production and feed sent from FCC to PPU. Now 3 rd Reactor is commissioned in PPU but not any changes in FCC for increase Propylene production. So kindly suggest me which type of changes is required in FCC technology or process data's to increase Propylene production.
 
Answers
13/08/2018 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
ZSM-5 gets the biggest change in propylene yield but it will have a dilution effect on catalyst activity, which will increase catalyst circulation. If you are stripper limited, you may also need to increase the catlyst activity to help get catalyst circulation rate back down. This can be accomplished by either increasing the fresh catalyst activity or by increasing the fresh catalyst make up rate.
10/08/2018 A: Sridhar Balakrishnan, Bharat Oman Refineries Limited , laksrid@yahoo.com
One of the ways would be increase the paraffinicity of the feedstock to FCC.
07/08/2018 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
I am assuming that you are referring to the spent catalyst stripper and not the stripper column. I am also assuming that the stripper dP is limiting the ability to maintain reactor/regenerator dP and that any increase in cat/oil ratio increases that dP. Reducing stripping steam would be a bad idea unless it is higher than needed. Increasing riser outlet temperature would increase cat/oil ratio, thus not good. You can focus on new catalyst formulations and mixes for increasing propylene yield.
07/08/2018 A: Saugata Palit, Johnson Matthey, saugata.palit@gmail.com
The easiest way to boost C3= yield from FCC is to use ZSM-5 additive.