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Submitted Chris Haslego, Nov 21 2011 11:21 AM | Last updated Nov 21 2011 01:29 PM

Category:	Refining
Question:	What is a good source of information about catalyst cooler operation, reliability and design for fluidized catalytic crackers.
Keywords:	fcc,catalyst,cooler,design,revamp
Answer:	UOP, Kellogg Brown and Root (KBR) and Stone and Webster all have catalyst cooler designs that are in commercial operation (the Stone and Webster Design was actually developed by the Bejing Design Institute in China). Each can probably supply you with contacts at refineries using their designs. All three cooler designs use essentially the same basic principles, but the hardware differs from licensor to licensor. From this standpoint, each design has both positive and negative aspects, and these differences must be weighed against your particular unit and needs. All three designs remove heat from a dense bed of catalyst located in the cooler vessel. Heat removal is through the generation of steam in tubes submerged in the dense bed. Hot catalyst enters the cooler from the regenerator bed. In most designs, cooled catalyst is returned to the regenerator using a standpipe and possibly a lift line. UOP also offers a "backmixed" design that does not require catalyst return lines (catalyst circulation to and from the cooler is controlled by fluidization air). Compared to flow through coolers, back mixed coolers have lower heat transfer rates. These dense bed coolers are considerably more reliable than older dilute phase coolers where the catalyst is blown through the tubes using air.