A thorough discussion on the use of leached asphalt as a feedstock for slurry bed reactors

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A magazine published an article signed by someone who advocated the idea of \"building solvent deasphalting units to produce DOA as a feedstock for slurry beds in order to solve the problem of periodic catalyst replacement in VRDS.\" Several experienced professionals in the industry teased me sarcastically, asking: By killing the chicken to get its eggs, will those eggs even be useful? I forced a wry smile and argued, \"Critical thinking is indeed something worth promoting in Mao Zedong’s thought, but it cannot overshadow the impulse of ignorance to shape history!\" To inspire slurry bed production, this post is created in a speculative manner; I am first presenting immature views for reference. Slurry-bed hydrotreatment of residue is an application of interdisciplinary science; it involves reaction control at both microscopic and macroscopic levels, as well as dispersion and transfer on the atomic and molecular scale, along with state transitions between different phases. Whether it is slurry-bed hydrotreatment of residue or direct coal liquefaction, a crucial aspect is ensuring high dispersion among the catalyst, hydrogen bubbles, the dispersed asphaltene phase, and the continuous gel phase. This is necessary to address issues such as reaction kinetic rate constants and coking resulting from bimolecular reactions during the lightening of residue. Therefore, the key to enabling the slurry bed to play its essential role and offer economic advantages lies in breaking up asphaltene clusters so that they remain highly dispersed within the reactor. Solvent deasphalting is essentially the reverse of this process; its outcome is the destruction of the efficiency of the slurry bed, a reduction in its effectiveness, losses for investors, and increased hardship for employees. Fixed-bed residue hydrogenation carries out the mission assigned to it within the overall process; however, the emergence of alternative energy sources will diminish its role in producing gasoline through combined catalytic processes. It is clear which type of reactor – fixed-bed or slurry-bed – will play a more important role in integrated refining operations in the future. The industry’s metaphor of \"killing the chicken to get the eggs\" is quite apt here. Moreover, the replacement cycle for VRDS catalysts can now approach 2 years, allowing for proper scheduling of catalyst replacements and maintenance activities without affecting operations. Additionally, there are still many unforeseen issues related to the deactivation of the post-treatment catalysts used in VRDS processing of DAO. In summary, I believe that using bitumen produced through leaching processes, which require large investments and high operating costs, as a raw material for slurry beds is an unconventional approach that is detrimental to such beds and not in anyone’s interest. It is nothing but a ridiculous industry practice based on nonsense, a tactic aimed at shifting responsibilities and deceiving oneself. Please point out any shortcomings!