STR Fluidized Bed Backmix

Related topics heat transfer. Section 3.4, dryers. Section 5.6 and size enlargement, Section 9.4. 

Phases GcS, GrS, LcS, GLcS Residence time for gas = seconds for solids = minutes to hours. Primarily for highly exothermic, very fast reactions where the need is for uniform, closely controlled temperature need fast reaction that occurs at the bottom of the bed. Not good if we have consecutive reactions to produce the product (because of backmixing). Relatively inflexible. Preferred over PFTR for strongly exothermic or endo reactions. Easier than fixed bed for catalyst regeneration, excellent heat transfer for high exothermic reactions lower pore diffii-sional resistance because of smaller diameter catalyst particles. Select if catalyst life is 3 month. Catalyst must withstand attrition. 

Gas with catalytic solid Solid residence time, 300-15 000 s gas residence time, 

Gas with inert soUd gasification or incineration use for homogeneous exothermic reactions where we need to control the heat release or for the creation of biogas from biomaterial (such as bagasse) in a fluidized bed of sand or incineration of wet sludge, again in a fluidized bed of sand. 

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