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Wet desulfurization is the method most commonly used for desulfuring coke oven gas. Whenever summer arrives and temperatures rise, it becomes very difficult to operate the desulfurization system; the efficiency of desulfurization declines, and the hydrogen sulfide level at the output of the system exceeds acceptable limits. This affects subsequent production processes, particularly the effectiveness of flue gas desulfurization, and in some cases, excessive sulfur dioxide levels in the flue gas may force a reduction in production capacity. The desulfurization reaction of coke oven gas is an exothermic process; in high-temperature environments, if no effective cooling measures are taken, the desulfurization efficiency will decline for both complexed iron catalysts and PDS catalysts as the temperature of the desulfurization liquid rises. In terms of desulfurization efficiency alone, complexed iron desulfurization requires a lower temperature; it is not necessary to keep the temperature below 35°C as in PDS desulfurization. However, regardless of the desulfurization technology used, a high temperature of the desulfurization liquid accelerates the formation of by-products salts. Additionally, excessively high temperatures affect the morphology of sulfur foam, which is detrimental to the formation and flotation separation of sulfur particles. For complexed iron desulfurization, the temperature of the gas entering the desulfurization tower is generally controlled to be below 30°C, with a maximum of 35°C. The temperature of the desulfurization solution should be 5–8°C higher than that of the gas to maintain water balance within the desulfurization system. However, it is preferable that the temperature of the desulfurization solution does not exceed 42°C; under no circumstances should it go above 45°C. Otherwise, both the desulfurization efficiency and the effectiveness in suppressing the formation of by-products will be severely affected. A coking plant in Xuzhou has two production lines. The desulfurization systems maintain a high efficiency in non-summer periods, with the hydrogen sulfide levels at the system outlet remaining below 20 mg/m³. During the hot summer months, the hydrogen sulfide level at the outlet of the desulfurization system in Workshop 1 remains below 20 mg/m³, whereas the levels in the desulfurization system of Workshop 2 exceed the allowed limits significantly. Both systems employ a complexed iron catalyst for desulfurization. The coal blending raw materials, proportions, and equipment configurations are identical in both systems. The only difference is that in Workshop 1, the temperature of the desulfurization solution is kept below 40°C; whereas in Workshop 2, due to equipment limitations, the temperature of the desulfurization solution remains at around 48°C, sometimes exceeding 50°C. This ultimately results in a serious exceedance of hydrogen sulfide levels at the system outlet. At the same time, the amount of by-product salt in Workshop 2 keeps increasing and cannot be effectively controlled. It is evident how much the temperature of the desulfurization liquid affects the desulfurization process. Therefore, before the arrival of the hot summer season, it is necessary to make advance arrangements to inspect or replace the factory’s refrigeration systems, the pre-cooling towers used in the desulfurization process (pre-cooling fluid heat exchangers, nozzles inside the towers), as well as the heat exchangers for the desulfurization fluid. This ensures that these heat exchange devices can effectively reduce temperatures, allowing the temperature of the gas entering the desulfurization tower and the temperature of the desulfurization fluid to remain within the appropriate operational ranges during the hot season. Only in this way can the desulfurization process proceed smoothly, thereby ensuring normal operation of the coke ovens.