干气提浓乙烯技术在茂名石化炼油厂的工业应用

The Commercial-Scale Application of Technology for Recovering Concentrated Ethylene from Dry Gas in Refinery of SINOPEC Maoming Company

茂名石化炼油厂催化和焦化装置副产的干气含有高附加值的乙烯,如果将其回收将会产生较大的经济效益。四川天一科技股份公司与中石化燕山分公司联合开发了回收催化干气中乙烯组分的干气提浓乙烯技术,并于2004年在燕山分公司获得工业应用,取得较大效益。干气提浓乙烯技术在茂名石化炼油厂的工业应用中,变压吸附单元采用两段变压吸附+吸附剂抽真空再生技术,能提高乙烯回收率;产品精制单元采用MDEA胺液洗涤+氧化锌精脱硫技术脱除杂质H2S;采用NaOH溶液碱洗方法脱除杂质CO2;采用四川天一科技公司脱氧催化剂和脱氧技术脱除杂质O2。应用情况表明,该技术能将炼油厂干气中的C2和C2+组分有效回收,并脱除H2S、CO2、O2等杂质,为乙烯裂解装置提供合格的原料气;同时,也暴露出一些问题,如:原料气带液,吸附剂粉碎,压缩机运行周期短,富乙烯气脱氧精度不易控制等,需要在今后的研究、设计和生产中继续改进和完善。

The dry gas produced as byproduct by the catalytic and coking units in the refinery of Sinopec Maoming Company contains high-value ethylene.Recovering this ethylene will bring the company much additional revenue.Sichuan Tianyi Science and Technology Co.,Ltd and Sinopec Yanshan Company have jointly developed a concentrated ethylene recovering technology used to recover ethylene components from catalytic dry gas and put it into industrial application in Sinopec Yanshan Company in 2004.The application has produced considerable economic benefits.In the application of the dry-gas concentrated ethylene extraction technology in the refinery of Sinopec Maoming Company,the pressure swing adsorption unit uses two-stage pressure swing adsorption ＋ adsorbent vacuum regeneration technology,which can raise the recovery of ethylene.The product refining unit uses MDEA amine liquid washing ＋ zinc oxide desulfurization technology to remove impurity H2S,the NaOH solution alkali wash method to remove impurity CO2 and deoxidizing catalysts and deoxidizing technology developed by Sichuan Tianyi Science and Technology Co.,Ltd to remove impurity O2.Application results show that this technology can effectively recover the C2 and C2＋ in refinery dry gas and simultaneously remove impurities like H2S,CO2 and O2 to supply up to standard feed gas to ethylene cracking units.Some problems have also been identified in the application such as liquid-containing feed gas,smashed absorbent,short operation cycle of the compressor and unreliable control of deoxidization accuracy of ethylene-rich gas.These problems need to be overcome in future research,design and production.