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What are the optimal unit configurations and combinations (e.g., FCC/hydrocracking) for increasing high-margins products, while reducing low-value streams (e.g., HSFO & LSFO)?

Mar-2023

Answers

Marcio Wagner da Silva, Petrobras, marciows@petrobras.com.br

The response depends on the characteristics of the processed crude, especially the sulphur content and API grade.

Regulations like IMO 2020 imposed severe restrictions over the refining hardware to process high sulphur crudes and the refiners capable of adding value to heavier and sour crudes reached significant competitive advantage. The synergy between FCC and hydrocracking units gives high flexibility and maximizes the refining margins, especially considering the growing market of petrochemicals but is a capital intensive solution and can be prohibitive for low capital power players.

Refiners processing medium and low sulphur crudes can apply the combination of FCC and solvent deasphalting or delayed coking units and reach significant added value to the processed crude with less capital expense, here it's necessary to consider that the refiner will need to rely with adequate hydroprocessing capacity to treat the intermediate streams and this needs to be considered in the investment analysis.

Another point to be considered is if the refiner needs to meet the market of bottom derivatives like asphalt or fuel oil. For these players it's necessary to consider that a deep conversion refining hardware like reached with the combination of FCC and hydrocracking can led to a lack of bottom barrel streams to produce these derivatives, with consequent opportunity lose (in some cases the refining margin is attractive for bottom derivatives like asphalt) and supply shortage in the market.

Mar-2023
Mel Larson, BECHT, mlarson@becht.com

Using the premise, that a plant has no coking process. The question boils down to hydrogen addition to carbon rejection and dehydrogenation. Another way of looking is to consider the C/H ratio of the feeds to the C/H ratio of the desired products. Considering this approach, the sequence of Hydrocracking before FCC with the FCC HCO as feed to the hydrocracker maximizes the first pass for hydrogen addition before carbon rejection and dehydrogenation. The desired sequence depends upon the variables of feed quality and the optionality between diesel and gasoline on a seasonable basis while lowering the bottoms product low value FCC bottoms. Further depending upon the sulfur and catalyst content of the net FCC bottoms it may have higher value as carbon black or premium pet coke feed vs bunker fuels.

Mar-2023