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In the wet flue gas desulfurization process, the oxidation and regeneration tank of the system not only carries out the task of oxidizing and regenerating the catalyst in the desulfurized rich liquid, but also serves to float sulfur bubbles. The flotation of sulfur foam in the regeneration tank involves air oxidizing hydrogen sulfide ions in the rich liquid into elemental sulfur, which then gets adsorbed on the surface of the foam, resulting in sulfur foam overflowing into the foam tank. During the production process, if abnormal phenomena such as weak bubbles or soap bubbles appear in the sulfur foam, you can refer to the following causes and corrective measures. Possible causes of the abnormal phenomenon of weak sulfur bubbles: 1. Improper treatment of coal or gas, or the presence of tar and surfactants that facilitate bubbling in the alkali source, which are carried into the desulfurization solution along with the gas, can lead to the formation of a large number of weak bubbles. 2. When adding ammonia water or alkaline solution to the system, adding a large amount of alkaline solution at once can easily cause numerous air bubbles to form in the oxidation regeneration tank. 3. When the temperature of the desulfurization liquid rises above 50°C, its viscosity and surface tension decrease, making it difficult for bubbles to form in the regeneration tank. However, if the temperature of the desulfurization liquid is too low (below 35°C), its viscosity increases, and foam forms in the oxidation regeneration tank; this foam floats on the surface of the tank in a cotton-like manner and is difficult to separate. 4. If the sulfur melting residue is returned to the system without treatment, especially when the temperature of this residue entering the system is too high, it can result in no foam being produced in the oxidation regeneration tank for two to three hours, or in a weak foam formation. Methods for dealing with the abnormal softness of sulfur foam: 1. Strengthen the pretreatment of gas to prevent substances prone to causing foaming, such as tar, dust, and other impurities in the gas, from entering the desulfurization solution. To address the issue of tar being introduced from the alkali source, the Guolitong closed-loop self-purification solution can effectively reduce the impact of foaming substances such as tar in the alkali source on desulfurization. 2. When adding alkali, it should be done in a regular and measured manner, avoiding single-large additions, in order to reduce or prevent the formation of void bubbles. 3. Adjust the desulfurization fluid cooling system in a timely manner; especially during summer, keep the temperature of the desulfurization fluid within an appropriate range to prevent it from becoming either too high or too low. 4. Before being returned to the system, the molten sulfur residue must undergo multi-stage sedimentation and cooling to a temperature of ≤40°C; during this process, a large amount of by-products in the molten sulfur residue precipitate and crystallize in the sedimentation and cooling tank. Only then can the clear liquid be returned to the system for reuse. Additionally, when the hydrogen sulfide inlet to the system is reduced, and the catalyst remains unchanged, the sulfur foam particles become smaller, which can also lead to a weak performance. Abnormal sulfur foam formation in the oxidation regeneration tank is caused by various factors; therefore, during troubleshooting, it is necessary to examine the causes from aspects such as the equipment, the process, and the use of catalysts, in order to address the root issues effectively. Coking desulfurization is more challenging to control due to the complex composition of coke oven gas; to ensure stability during production, a more specialized technical team is required to provide continuous technical support.