Improving the fluid catalytic cracking unit in term of energy consumption, a simulation study

Fluid catalytic cracking (FCC) process is a unit that converts heavy distillates like gas oil or residues to gasoline and middle distillates using cracking catalyst. Increased global focus on reducing energy consumption and emissions are working together to make FCC unit power recovery more attractive. The flue gas temperature from the FCC unit was about 700-750oC and it holds a lot amount of energy. The heat recovery steam generated (HRSG) was used to recover the heat of fluegas to generate a steam and electricity. Aspen HYSYS (version 7.0) software was used to calculate the energy that will be recovered. From the simulation, besides from the based case, four adjustment of the parameter was made which is the steam pressure requirement, flowrate of feedwater, outlet steam turbine pressure and the efficiency of the steam turbine. The result was obtained by all that adjustment as shown in Section 4.1. For the based case of this study, the required steam pressure, temperature and mass flow was 600psig, 500oC and 45000kg/hr meanwhile for the fluegas was 34psig, 715oC and 241800kg/hr. The electric power generated was 1.46MW. For the adjustment of parameters, it is to know the amount of the electricity at a difference condition. As a conclusion, the objective of this study was achieved by improving the FCC unit in term of energy recovery