MODELING OF FLOW AND HEAT-TRANSFER IN FLUIDIZED CATALYTIC CRACKING RISER-TYPE REACTORS

This paper presents a three-dimensional, two-phase flow and heat-transfer analysis of particles conveyed by gases in vertical pipes. This type of flow is found in many engineering applications and used in the riser reactor section of a Fluidized bed Catalytic Cracker (FCC). The phases involved are gas and catalyst particles. The analysis involves the formulation and the simultaneous solution of the differential equations describing the above processes. The solution of the relevant equations is effected by an efficient finite-difference procedure. It is concluded that effects of gas-injection geometry on flow field and temperature distribution inside the reactor can be predicted realistically. This work is a necessary background for the simulation of a catalytic cracking reaction, which takes place in a riser-type reactor.