Hydrogenation issue
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What are the advantages of using a thermal hydrocracking process in hydrogenation units, and what are the advantages of using a cold hydrocracking process? What scale of processing volume is suitable for using the thermal high-temperature separation process?
Reply 1# hjdform: A value of over 1.8 million is appropriate; it offers high thermal efficiency and helps save energy, but it requires a lot of hydrogen and thus imposes high demands on the material quality. A value below 1.8 million is not suitable.
The low-temperature heat utilized by us is 1 million tons
Generally, the reaction section of a hydrocracking unit can be divided into a cold high-pressure fractionation process and a hot high-pressure fractionation process. The main difference between the cold and hot high-pressure processes is that the hot separation process requires the installation of a hot high-pressure separator and related equipment. Factors to consider in the reaction section include the purity of recycled hydrogen under the two process scenarios, the amount of dissolved hydrogen, changes in the load on the heating furnace, as well as the resulting changes in the specifications of key equipment, investment costs, and operating expenses. The reaction effluent from the cold separation process is cooled to an appropriate temperature, typically 40–60°C. The cold separation process can enhance the ability of the produced oil to absorb conventional gas components C1, C2, C3, and C4 by controlling the separation temperature; moreover, the low temperature of the produced oil results in a low solubility for hydrogen, thereby improving the purity of the recycled hydrogen. However, this process results in a significant loss of thermal energy from the reaction effluents. The thermal separation process can improve the thermal energy utilization rate of the reaction effluent stream, reduce the cooling load on the reaction effluents, and decrease the area required for cooling heat exchange equipment. Importantly, it prevents the deposition and clogging of polycyclic aromatic hydrocarbons in the air cooler tubes; however, it does reduce the hydrogen concentration in the circulating hydrogen. If low-pressure hydrogen recovery is available, use high-pressure heat more often.
Learning about the process flow of *hydrogenation units currently