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This post was last edited by zhuheqing on 2024-6-28 09:06. Abroad, the hydroprocessing units for slurry-bed residue generally adopt a design in which one tubular reactor corresponds to one thermal hydrocracker. With the stable operation of industrial plants in China, the development of technologies related to hydrocracker internals, improved capabilities in manufacturing forged and welded high-pressure equipment, and the successful application of advanced control systems, it has become possible to optimize the selection of thermal hydrocracking solutions. The reasons are as follows: First, the purpose of the slurry-bed thermal hydrocracker is to achieve rapid initial separation of gas, liquid, and solid phases; its main function is to reduce the amount of slurry mist in the gas stream, as well as the presence of coke and metals, thereby preventing blockages in the tubes of the hydrogen heat exchange system； At the same time, it controls the short residence time of the slurry, stops the reaction by hydrogen saturation, and reduces the exothermic polymerization of the slurry as well as bottom coking; therefore, the design features a large gas-phase volume with low flow velocity, along with a low liquid level in the liquid phase and a conical shape. II. Unlike trickle-bed hydrogenation, the slurry-bed thermal cracking gas phase includes an oil washing system that cleans the \"dirty\" oil while recovering light hydrocarbons and light oils and transferring them to the atmospheric pressure system. This process design employs high-flow-rate threaded locking rings for hydrogen-hydrogen heat exchange, thereby creating the prerequisites for optimizing the thermal cracking process. III. Can the design of one high-temperature separator per reactor being in one-to-one correspondence be optimized to “two reactors and one high-temperature separator”? After consulting on the manufacturing capabilities of One Heavy and professional CFD simulations for flow fields, it has been determined that the two 5m-diameter High-Temperature Hydrogenation reactors can fully accommodate a High-Temperature Hydrogenation unit with a symmetric tangent arrangement and a diameter of up to 6m. This optimization facilitates greater stability in the gas separation flow field as well as a shorter residence time for the slurry. The foaming situation in the upper part of the reactors can be assessed based on density, temperature rise, and the horizontal temperature of the overflow line; the difference in load between the two tangent arrangements depends entirely on the feed at the bottom of the reactors, as well as the amounts of primary and secondary hydrogen and the initial reaction temperature. IV. The use of specialized heat-high-pressure internal components can reduce the diameter and height of the heat-high-pressure unit; optimization is possible at least on the basis of a conservative theoretical diameter of 5m for an existing gas flow rate of 3.2m. When the LL liquid level plus the volume at the cone bottom meet the safety requirements specified in the design guidelines, optimizing the distance from the feed liquid inlet to the liquid surface under HH conditions can reduce the height of the liquid phase. V. Combining high-temperature processes can reduce the need for high-pressure slurry pipelines at the bottom, high-pressure valves and control valve assemblies, slurry valves, as well as nuclear level density meters. It also alleviates the problem of a dense arrangement of components within the reaction framework, increases the flow velocity in the slurry pipelines, reduces the number of slurry valve channels and associated stress levels. In this way, space is saved, operation becomes safer and more convenient, and significant investment savings are achieved. 6. The integrated, serialized, and standardized design of the \"two reactions and one high-temperature separation\" system enables the standardization of reactors with capacities of 2 million tons per year, 4 million tons per year, and 6 million tons per year, as well as of high-temperature separation units, slurry valves, high-pressure control valves, hydrogen valves, and hydrogen furnaces for heat transfer. This facilitates the design, manufacturing, and installation processes for such projects, as well as model design, modular installation, and factory-based production.