摘要
对国内炼油厂MTBE总硫含量偏高的原因进行了分析。指出液化石油气脱硫醇过程中产生的RSSR(二硫化物)液滴直径小、与碱液的密度差小,且碱液的黏度较高,这些因素使RSSR无法仅靠重力作用从碱液中脱除,在碱液循环过程中又被反抽提至液化石油气中,造成液化石油气总硫含量超标。另外,MTBE装置催化剂的磺酸基团脱落也会造成MTBE产品硫含量升高,但增加量一般不会超过10μg/g。采用在二硫化物分离罐中增设促进RSSR聚集的内构件等措施可强化碱液与RSSR的分离。当对MTBE硫含量提出更高要求时,可采用分馏的方法将MTBE原料中的硫化物除去。国内已在研究用吸附法脱除MTBE原料中RSSR,但目前处于起步阶段。
The causes of higher total sulfur in MTBE product in domestic refineries were analyzed.It was pointed out that,in LPG sweetening process,the liquid droplet diameter of generated RSSR（bisulfide） was small,the density difference between RSSR and alkaline was also small,and the viscosity of alkaline was high.All of these made it difficult for RSSR to be separated from alkaline merely by gravity.Meanwhile,RSSR was anti-extracted from alkaline to LPG,causing LPG total sulfur content exceeding standard specification.Moreover,the falling off of sulfonic acid radical in catalyst of MTBE unit also led to build-up of sulfur in MTBE product,but the increase would not generally exceed 10 μg/g.The installation of internals which could help bisulfide accumulation in bisulfide separation drum would intensify the separation of RSSR from alkaline.If stricter requirement for sulfur content of MTBE was a necessity,distillation approach could be applied to remove sulfides from MTBE.In China,research efforts are being made to remove RSSR from MTBE by absorption process,but it is in the preliminary stage.
出处
《炼油技术与工程》
CAS
2011年第12期14-18,共5页
Petroleum Refinery Engineering
