Dear all,

My question is related with the potential problems that could appear when the feedrate in a FCCU is reduced to the technical minimum (turn-down) or below.

– According to your experience, what is the minimum feedrate that can be processed in a FCCU? 60% of nominal feedrate or does anyone operated below this point?
– Which are the most likely limitations that could appear in this point?
1. Insufficient gas flow rate to the wet gas comppresor?
2. Insufficient pressure or delta P in feed nozzles? Problems to obtain a suitable vaporization?
3. Insufficient coke production to close heat balance?
4. Insufficient liquid-vapour traffic in the main fractionation?
5. Any other limitation?

Thank you very much for your collaboration

Best regards
Dear all,

My question is related with the potential problems that could appear when the feedrate in a FCCU is reduced to the technical minimum (turn-down) or below.

– According to your experience, what is the minimum feedrate that can be processed in a FCCU? 60% of nominal feedrate or does anyone operated below this point?
– Which are the most likely limitations that could appear in this point?
1. Insufficient gas flow rate to the wet gas comppresor?
2. Insufficient pressure or delta P in feed nozzles? Problems to obtain a suitable vaporization?
3. Insufficient coke production to close heat balance?
4. Insufficient liquid-vapour traffic in the main fractionation?
5. Any other limitation?

Thank you very much for your collaboration

Best regards