Comparative Study of Various Thermal Boundary Conditions onFCCU Riser Reactor Wall

The performance of a fluidized bed catalytic cracking unit (FCCU) withgas oil feed in the various thermal conditions of the riser wall isinvestigated. Four different thermal boundary conditions on the riserwall, namely adiabatic (A), non-adiabatic (NA), a constant heat fluxinroduced on the wall (CFW) and isothermal wall (IW) are studied.Results show that the best operating mode for the light gas yield is thecase of CFW boundary condition and the best process performance interms of gasoline yield is corresponding to isothermal wall. In addition,the coke formation in the case of CFW boundary condition is aboutthree or more times larger than other cases while in the case of IW thiswill not increase rapidly as the CFW mode