硫磺回收装置烟气二氧化硫排放影响因素分析及对策

Influence factors and countermeasures of sulfur dioxide emission in flue gas of sulfur recovery unit

分析了中国石油兰州石化公司3万t/a硫磺回收装置烟气二氧化硫(SO2)排放浓度超标的原因,并采取了相应的改造措施。结果表明,气体精制氧化尾气硫化物含量高,系统燃料气硫含量高,集中溶剂再生贫液质量差是造成烟气SO2排放浓度超标的主要原因。通过采取将气体精制氧化尾气由硫磺尾气焚烧炉焚烧改至酸性气燃烧炉进行焚烧,脱硫后净化干气取代系统燃料气作尾气焚烧炉燃料,尾气处理溶剂由集中再生改为独立再生等措施,使烟气SO2排放浓度由大于600 mg/m3下降至不超过80 mg/m3。

The reasons for exceeding standard of sulfur dioxide concentration in flue gas emission of 30 kt/a sulfur recovery unit of Lanzhou Petrochemical Company,PetroChina were analyzed,and corresponding revamping measures were adopted.The results showed that high sulfide content in oxidation exhaust gas of gas purification unit,high sulfide content in fuel gas and poor quality of regenerated lean solution were the main factors which caused the excess emission of sulfur dioxide.By adopting the revamping measures,such as burning the oxidation exaust gas in sour gas burner instead of in sulfur recovery flue gas burner,replacing the present fuel gas with desulfurized dry gas,changing central regeneration of absorption solvent to individual regeneration,the sulfur dioxide concentration in flue gas emission decreased from more than 600 mg/m3 to less than 80 mg/m3.