Fluidized-bed catalytic cracking is one of the most commonly used processes in petroleum refining to convert heavy high-boiling point components of crude oil into gasoline and distillate components.
An energy conservation measure for such a process, utilizes an axial flow compressor which furnishes air for combustion in the regenerator where the coke deposits are burned off the catalyst and also drives the catalyst through the system.
The flue gases from the regenerator are expanded in an expansion turbine which drives the compressor, whereas the excess energy is used to drive an electric generator. The exhaust gases are utilized further in a heat recovery boiler to produce process steam.
A parametric study involving variation of air pressure and expander inlet temperature using specially devised computer program, was used to analyse the performance of the proposed system. Furthermore, the system is economically evaluated and compared with the conventional cracking system using a gas turbine engine. The proposed system offers leading performance and economic advantages in comparison with the conventional one.