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Q Considering market shifts favouring petrochemicals (for example, chemical-grade propylene), what are the optimal unit configurations and combinations, such as FCC/hydrocracking, for increasing high-margin products while reducing low-value streams, such as high sulphur fuel oil (HSFO) and low sulphur fuel oil (LSFO)? A Arun Arora, arun.arora@lummustech.com, Daniel Gillis, Daniel.gillis@lummustech.com, Theo Maesen, tmae- sen@chevron.com , Chevron Lummus Global The optimum configuration depends on global, regional, and local economics. While finalising the optimal configuration, it is critical to consider optimum use of H2 (avoid product give - aways) and integration of similar pressure level units. The integration offers Capex and, more importantly, energy effi - ciency, which is critical going forward. The availability of online training simulators and other digital solutions (where licensor input can be integrated) is also key for large, integrated com - plexes to realise maximum value from the investment. A few selected optimum configurations are depicted below. The configuration for each refiner and objective is not limited to the following. The available technologies can be rearranged to meet the desired objectives. The key is to have experts in these technologies working together to offer optimum solutions and access to hundreds of propri - etary technologies: For maximising chemicals as objectives – either as a standalone or ‘bolt-on’ project for an existing refinery (see Figure 1 ) For existing refineries with a large coker making ‘pet - coke’, the resid upgrader can help to upgrade coke to higher value green or anode coke (see Figure 2 ) Needle coke for graphite electrodes – adding a new coker to make needle coke can offer attractive returns, especially if the right feed such as FCC slurry oil and/or coal tar is available LC-Fining with integrated HCR or HDT – a commercially proven configuration LC-Max with integrated HDT or HCR for maximum conversion
More liquid products
Lower sulphur coke
LC-Fining or RDS
Coker
Figure 2 Maximising value from coker unit configurations
RDS + FCC can be another configuration if the objective is to maximise very low sulphur fuel oil (VLSFO), but this configuration is crude slate dependent. There are alternate new schemes for the objective available if plot space is lim - ited and/or catalyst life is desired Single Regenerator Dual Catalyst (SRDC). A Nieves Álvarez, Senior Advisor in Oil Refining/ Petrochemical Technology, MERYT Catalysts & Innovation, nalverez@meryt-chemical.com The optimal reduction of HSFO and LSFO streams goes through more units than simply hydrocracking and FCC. These include completing the conversion section with coker units and possibly recycling the streams from this unit back to hydrotreatment and FCC. Additional options include high-pressure hydrotreatment of heavy fractions (upgraders), such as HDH, Husky, and slurry beds, but they are also more expensive processes in terms of Opex and Capex. Several technology companies in the market offer other processes, such as deasphalting with solvents, solvent extraction, and solvent dewashing, if refineries can process the solids generated. In the future, it seems that the use of hydrocracking, residue fluid catalytic cracking (RFCC), and coker could be advantageous if FCC CO2 emissions can be captured and converted with biohydrogen, green hydrogen towards e-fuels, olefins, and aromatics. Of course, each of these alternatives will depend on the crude oil processed in the refinery, its product market and, most importantly, the capi - tal investment the refinery is willing to make.
H
Light oil
H
Heat
Cooling
Middle oil
CRUDE OIL
Tailored separation
Trickle ow reactors
Steam cracker
CHEMICALS
Desalter
C +
Low-value streams
Liquid circulation reactors
Heavy oil
Pyrolysis fuel oil
Trickle ow reactor
VLSFO
Figure 1 Flexible configuration for maximising chemicals production
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PTQ Q2 2023
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