Study of different operating parameters of fcc unit with aspen-hysys

Abstract

Fluid catalytic cracking unit (FCCU) is known as the heart of the modern refinery process. An FCC gives a product specific process eliminating undesired products to a larger extent. While it is mostly used to increase the production of gasoline, it also has the ability to give different products like propylene and butylene under different conditions. Crude oil contains hundreds of hydrocarbons from light gases to molecules boiling above 343 °C, most of the molecules being in the higher end. About 30 % of the feed to the distillation column cannot be separated into usable fractions in the market. FCC uses this as its feed, the atmospheric gas oil and vacuum gas oil. An FCC is used to produce low molecular weight compounds like gasoline from heavier molecules by the process of catalytic cracking. In this project, a basic refinery process was designed and the atmospheric gas oil from the distillation column was used as feed in the FCC unit.The plant data was referred from the plant data collected by Theologous et al. in which few changes were made in order to achieve proper simulation. A variation of certain parameters was also carried out to give a view of the effect of these parameters on the production of Naphtha, coke and the total conversion in the FCC unit. Two different catalysts were also used and product yield was noted. The effect of dual riser with respect to one riser was also carried under a specific range.