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Coke oven gas from coking plants contains large amounts of hydrogen sulfide, which can corrode equipment and pollute the environment during the production process; it also has a significant impact on subsequent processing steps. Therefore, the removal of hydrogen sulfide is an important step in the recovery of valuable products from coking enterprises. Currently, most coking plants use PDS or complexed iron catalysts to remove hydrogen sulfide in the desulfurization process. Regardless of the catalyst used, the quality of regeneration of the desulfurization solution is a key factor affecting the long-term proper operation of this process. The principle of the regeneration of complex iron catalysts for desulfurization is to utilize oxygen in the air to oxidize divalent complex iron into trivalent complex iron, thereby restoring its desulfurization capability. Most desulfurization processes in coking plants employ two-stage desulfurization with twin towers in series, and the desulfurized rich liquids cannot be mixed. Due to the high selectivity and high desulfurization efficiency of the complexed iron catalyst, the absorption load distribution in secondary desulfurization becomes uneven, as does the regeneration load. The first stage of desulfurization has a high load but insufficient regeneration, while the second stage has a low regeneration load resulting in a low equipment utilization rate. Prolonged uneven load distribution can lead to severe insufficient regeneration of the first-stage desulfurization process, rapid increase in by-products, increased density of the desulfurization solution, and higher catalyst consumption. In severe cases, it can lead to a decrease in desulfurization efficiency and blockage of the packing pipes due to the crystallization of by-products. The low regeneration load at the second desulfurization stage results in a high sulfur content in the rich liquid, which can easily cause clogging of the bottom packing. Therefore, the quality of desulfurization regeneration determines the stable operation of the desulfurization process. There are significant differences among various coking plants in terms of the equipment used for desulfurization, the processes chosen, and the subsequent uses of the gas produced; as a result, the effectiveness of desulfurization and regeneration also varies. How can the regeneration of the desulfurization fluid in the desulfurization process be optimized to meet the requirements of production? Appropriate adjustments to the desulfurization regeneration process based on actual conditions can yield good results: 1. Select and control an appropriate catalyst concentration according to the overall desulfurization load. 2. Strive to achieve a balanced regeneration load by mixing the rich liquid from the secondary desulfurization process. 3. Use the gas bypass to adjust the absorption load and regeneration load of the secondary desulfurization process. 4. For units where subsequent processes have low requirements for hydrogen sulfide, two towers can be operated in parallel to balance the desulfurization absorption load and the regeneration load. 5. Different catalyst concentrations are used to control secondary desulfurization; however, due to the influence of sulfur foam slurry, the effectiveness of this method is not particularly significant. 6. For tower regeneration, increase the amount of regenerating air as much as possible while maintaining the thickness of the sulfur foam. When using spray regeneration, it is necessary to clean the injectors regularly to prevent a decrease in air intake due to blockages; forced air supply can also be employed. Only by adapting measures to the specific conditions of each desulfurization unit, and by taking into account various aspects such as the design phase, appropriate equipment modifications, the determination of process routes and parameters, as well as daily operation management, can it be ensured that the desulfurization liquid is regenerated adequately to meet the needs of the system’s production.