I would like to ask for ways to reduce the formation of sulfates in the process of converting sulfur recovery waste gas into sodium sulfite
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Experts: I am a production manager involved in the process of producing sodium sulfite through alkaline absorption of exhaust gases from sulfur recovery (Claus) processes. After years of optimization, the sodium sulfite production unit in my company operates very stably, with waste emissions meeting regulatory standards. The sodium sulfite produced has an excellent crystal structure and high brightness. However, the concentration of sodium sulfite in the product is between 90% and 93%; analysis shows that the remaining component is mainly sodium sulfate. Does any expert have a way to reduce the formation of sodium sulfate? I would appreciate your advice. Thank you.
If oxygen is isolated, then sodium sulfate won’t be formed, right? 1. The oxygen content in the exhaust gases should be as low as possible ； 2. Deoxygenation of the absorption liquid.
1: Add antioxidant to the absorption circulating fluid； 2: Mainly, the ratio of sulfur dioxide to sulfur trioxide in the exhaust gases is not high. The alkali absorption method absorbs sulfur dioxide, as well as sulfur trioxide; some acid mist is also absorbed. This results in a low sodium suboxide content. To increase the sodium suboxide content, some of the gas from the absorption tower can be replenished.
Before producing sodium sulfite, substandard sodium sulfite is used as a deoxygenation scrubber for sulfur dioxide gas; taking advantage of the easy oxidizability of the sodium sulfite aqueous solution, oxygen in the gas is removed, after which sodium sulfite or sodium metabisulfite is produced.
SO2 can be returned to the system in a renewable manner
Hello, we can discuss this. The considerations should mainly focus on air leakage from the equipment itself, the oxygen content limits in the exhaust gases, concentration and crystallization, as well as centrifugal drying. If those measures still don’t work, introducing antioxidants may be necessary; however, the antioxidants available on the market are not cost-effective. If it’s convenient for you, please provide the detailed parameters.