摘要
环丁砜(C4H8SO2)是无色、溶于水、高极性和具有良好热稳定性的化学产品,其毒性很低,密度较高、比热低、沸点高。大庆石化公司化工一厂两套芳烃抽提装置均采用UOP生产技术,以环丁砜溶剂作为萃取剂,将加氢汽油中的苯、甲苯和二甲苯萃取出来,然后经过精馏,得到高纯度的苯、甲苯和二甲苯。日常生产中,在220℃以下时,环丁砜溶剂分解速度比较慢,但超过220℃时,随着温度的升高,其分解速度急剧上升,过高的温度将促使环丁砜分解生成浅黑色的聚合物(聚丁二烯和氧化铁混合物)和SO2,因此,应严格控制溶剂系统的温度和加热蒸汽的温度;有空气存在时,由于空气的氧化作用,溶剂系统中SO2的释放量要比没有空气存在时多,应做好措施防止空气进入生产系统。环丁砜溶剂在使用过程中,虽然由于产生的分解物会对生产造成一定影响,但通过对抽提系统的原料罐、溶剂罐及反洗罐加氮封及单乙醇胺加入流程的改造,可以减缓环丁砜溶剂的分解速度;对抽提工段的换热器进行更换,可以防止环丁砜分解物对换热器的腐蚀;对贫溶剂换热器的扩容及定期对抽提塔进行水洗,可以提高抽提塔的生产负荷,保证产品质量;对二甲苯塔操作参数进行调整,降低环丁砜的分解速度和对二甲苯塔加热器的腐蚀。
Sulfolane （C4H8SO2） is a colorless,water-soluble,high-polarity chemical product with good thermal stability.Its toxicity is very low,density is relatively high,specific heat is low and boiling point is high.The two aromatic extraction units in the Chemical Plant No.1 of Daqing Petrochemical Company both use UOP＇s production technology.Using sulfolane solvent as the extraction agent,the units extract the benzene,methylbenzene and dimethylbenzene in hydrogenated gasoline and rectify them to obtain high purity of benzene,methyl- benzene and dimethylbenzene.In routine production,when the temperature is lower than 220℃,sulfolane solvent decomposes at a low speed,while when the temperature exceeds 220℃ ,as the temperature rises,its decomposition speed rises sharply.High temperature will facilitate the decomposition of sulfolane into a light-black polymer（a mixture of polybutadiene and ferrous oxide） and SO2.For the above reasons,the temperatures for the solvent system and the heating steam should be strictly controlled.When the air is present,due to the oxidation of the air,more SO2 will be released from the solvent system than when no air is present.Measures should be taken to prevent the air from entering the production system.In practical use of sulfolane,although the products from the decomposition have a certain effect on production,the decomposition of sulfolane solvent can be slowed down by optimizing the nitrogen sealing for the feedstock tank ,the solvent tank and the backwashing tank of the extraction system and the mono ethanolamine filling process.Replacing the existing heat exchanger in the extraction section can prevent the corrosion of the products from the decomposition of sulfolane to the heat exchanger;expanding the capacity of the lean solvent heat exchanger and washing the extraction tower on a regular basis can raise the production load of the extraction tower and ensure product quality;adjusting the operating parameters of the dimethylbenzene tower can reduce the decomposing speed of sulfolane and the corrosion to the heat exchanger of the dimethylbenzene tower.
出处
《中外能源》
CAS
2011年第2期95-99,共5页
Sino-Global Energy
关键词
芳烃抽提装置
环丁砜
单乙醇胺
腐蚀
措施
aromatic extraction unit
sulfolane
mono ethanolamine
corrosion
measures
