Şeyma Avcılar - TUPRAS - Izmet Refinery
Aytaç Gül - TUPRAS - Izmet Refinery
The FCC unit can serve as a lifeline when refineries have a surplus in some half-products, thanks to its robust nature and “flexible” constraints in feedstock, catalyst and operation parameters. By taking the correct measures and close monitoring, it is possible to process considerable amounts of hydrocracker bottoms when the hydrocracker unit decreases conversion due to HPNA as well as a heavy and already thermally cracked stream like HCGO when there is surplus. Inclusion of HCGO and UCO (unconverted oil) streams in FCC feedstocks provides a considerable benefit- it provides an escapeway from cutting down of capacity of the two most “valuable” units in the refinery in addition to positive effects on ‘some’ FCC operation parameters and products qualities. However, there are also disadvantages such as loss of conversion and undesired changes in product qualities. It is crucial to take into account all these cons and pros and optimize the feedstock both in terms of refinery profitability as well as unit specific constraints and reliabilities. In this presentation, the effects of processing HCGO, UCO and import HVGO on product qualities and operation parameters and the key factors to take into consideration while selecting import HVGO are discussed in detail.