Maximization of propylene in an industrial FCC unit

The FCC riser cracks gas oil into useful fuels such as gasoline, diesel and some lighter products such as ethylene and propylene, which are major building blocks for the polyethylene and polypropylene production. The production objective of the riser is usually the maximization of gasoline and diesel, but it can also be to maximize propylene. The optimization and parameter estimation of a six-lumped catalytic cracking reaction of gas oil in FCC is carried out to maximize the yield of propylene using an optimisation framework developed in gPROMS software 5.0 by optimizing mass flow rates and temperatures of catalyst and gas oil. The optimal values of 290.8?kg/s mass flow rate of catalyst and 53.4?kg/s mass flow rate of gas oil were obtained as propylene yield is maximized to give 8.95?wt%. When compared with the base case simulation value of 4.59?wt% propylene yield, the maximized propylene yield is increased by 95%.