The unit converts heavy products into higher value products such as gasoline and lighter products. However, a heavy carbon product (catalyst coke) is produced during cracking. The process mainly consists of a reactor, a fractionator and a catalyst regeneration system. Fluid catalytic cracking, the catalyst is fluid and circulates around, is the most used process in the refinery complex. Correlations for yield obtained from regression of plant data using a zeolite catalyst (Fahim, Alsahhaf, & Elkilani, 2010). The correlations are shown below: Table 18: FCCCoke Product Correlations wt%= 0.05356 * CONV – 0.18598 * API + 5.966975LCO LV%= 0.0047 * CONV2 – 0.8564 * CONV + 53.576 Gases wt% = 0.0552 * CONV + 0.597Gasoline LV%= 0.7754 * CONV –