Causes of abnormal sulfur foam flotation and treatment measures

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During the production process, abnormal phenomena may occur with the sulfur foam generated in the regeneration tank or high tower. It is manifested by abnormal conditions such as a low amount of sulfur foam, no foam, weak foam, and frothy foam. Next, we will explore the causes of abnormal sulfur foam flotation and the corresponding treatment measures. I. Analysis of the causes of sulfur foam abnormalities 1. Due to improper pretreatment of gas, substances prone to foaming such as tar, dust, and other impurities contained in the gas are carried into the desulfurization solution, which can result in either no sulfur foam in the oxidation regeneration tank or the formation of a large number of weak bubbles. 2. 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 solution is too low (below 35°C), its viscosity increases, and foam forms in the oxidation and regeneration tank; this foam floats on the surface of the tank and is difficult to separate. 3. 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 not only causes bubble formation and abnormal bubbling in the oxidation regeneration tank but also increases the amount of by-products in the desulfurization system. 4. When the ammonia water condensed in the ammonia vaporization tower is directly introduced into the reaction tank or the desulfurization tower, it may cause the foam to become weaker. Additionally, if the ammonia gas or ammonia water from the ammonia vaporization tower enters the pre-cooling tower, it can also lead to weakened foam. 5. Excessive control of the liquid level in the regeneration tower results in an insufficient thickness of the foam layer, making it easy for the foam to be blown away and leading to a surface free of foam. II. Handling of sulfur foam abnormalities 1. Strengthen the pretreatment of gas to prevent substances prone to foaming, such as tar, dust, and other impurities in the gas, from entering the desulfurization solution. 2. Strengthen the control of desulfurization temperature. 3. The residue remaining after sulfur melting needs to be settled or filtered, and then cooled before being returned to the system. It should not be returned in large quantities at once; rather, it needs to be added to the system in controlled amounts on a continuous basis. In addition, it is also necessary to strengthen the control of the sulfur melting or sulfur recovery system, to increase the concentration of the sulfur foam liquid in the sulfur melting vessel as much as possible and reduce the amount of residual liquid. 4. Ammonia vapor from ammonia water should not be returned directly to the desulfurization system; it is better to send it back to the previous processing stage, where it can be treated before being carried along with the gas. 5. The liquid level in the regeneration tower should not be controlled at too high a level; this is done to increase the residence time of bubbles in the solution, thereby giving the bubble surfaces more opportunities to adhere to more elemental sulfur particles and helping to maintain a stable thickness of the sulfur foam layer on the surface of the tank. 6. For devices that use jet regeneration, it is necessary to regularly check the amount of air drawn in by the injector as well as any changes in the sulfur foam on the surface of the tank. Blockages within the nozzles and throat sections should be identified and removed promptly, so as to ensure an optimal level of oxygen absorption by the self-priming injector and to maintain a stable blowing intensity in the oxidation regeneration tank. In summary, the abnormal formation of sulfur foam in the oxidation regeneration tank is caused by various factors. Therefore, when addressing this issue, it is necessary to investigate the causes from aspects such as the equipment, the processing procedures, and the use of catalysts, so as to find appropriate solutions and resolve the underlying problem.