A Residue FCC (RFCC) unit expands the versatility and profitability of an FCC to crack a wider variety of feedstock:
++ Traditional FCC feedstocks
++ Deeply Deasphalted Oil
++ Atmospheric Residue
++ Vacuum Residue
The quality of the feed is the main determinant of the yields and product properties. The yield of valuable gasoline and LPG products in the unit will be mainly influenced by the hydrogen content of the feed. Feed contaminants such as sulfur, nitrogen, Conradson Carbon Residue (ConC) and metals also impact the yield and/or product quality. As a result it is often advantageous to either partially or fully hydrotreat the feedstock to improve the hydrogen content and reduce the level of contaminants. The entire system needs to be designed to work in concert to meet the desired performance objectives:
· Maximum Distillate (low severity)
· Maximum Gasoline
· Maximum Gasoline x Octane or "Octane-Barrels"
· Maximum LPG and Gasoline or "High Propylene"
· Maximum Propylene
· Maximum Distillate & LPG