炼油厂增产乙烯原料措施及建议

Measures and suggestion for increasing production of ethylene feedstock from refinery

关键词:  乙烯原料  PONA  BMCI值  原料优化

Key words:  ethylene feedstock  PONA  BMCI value  feedstock optimization

摘要:

分析了影响直馏石脑油和加氢尾油裂解性能的主要因素,根据进口油、玛湖油、牙哈油价格,以及石脑油馏分PONA和模拟裂解产物收率情况,增加炼油厂进口油掺炼比例、降低玛湖油和牙哈油掺炼比例,不仅有利于生产乙烯原料,也有利于提高全厂经济效益。优化催化柴油加工路线,汽柴油加氢装置不再加工催化柴油,加氢石脑油干点由190 ℃提高至230 ℃,仍是优质的乙烯原料。对蜡油加氢裂化催化剂进行更换,有效降低了尾油BMCI值,为进一步增产尾油创造了条件。新建干气低分气单元,实现炼油新区加氢干气、低分气及火炬气中轻烃的有效回收,蒸馏装置实施停运脱乙烷塔技术改造,简单高效回收C₂⁺组分。通过实施增产乙烯原料措施,乙烯原料自给率提高2.49百分点。催化和焦化干气C₂⁺组分占炼厂待回收资源的67%,且乙烯资源丰富,建议优先回收。建议当汽油过剩时,加氢轻石脑油全部用作乙烯原料；当柴油或航煤过剩时,常一线或航煤用作乙烯原料。 

Abstract:

The main influence factors of cracking performance for straight-run naphtha and hydrocracking tail oil were analyzed. Based on imported oil, Mahu oil, Yaha oil prices, as well as naphtha fraction PONA and the simulate cracking product yield, it was not only beneficial to the production of ethylene feedstock, but also to improve the economic benefit of the factory by increasing the blending proportion of imported oil in the refinery, and reducing the blending proportion of Mahu and Yaha oil. After optimizing the processing route of FCC diesel, gasoline and diesel hydrotreating unit will not process FCC diesel, the final point of hydrotreating naphtha was lifted from 190 ℃ to 230 ℃, and it was still a high-quality ethylene feedstock. The hydrocracking catalyst was replaced which effectively reduced BMCI value of tail oil and created conditions for further increase of tail oil production. A new dry gas and low division gas unit was built to realize the effective recovery of light hydrocarbons in the hydrogenated dry gas, low division gas and flare gas in the new refining area, the distillation unit implemented the transformation of shutting down deethane column to simply and efficiently recover C₂⁺ components. Through the measures of increasing the production of ethylene feedstock, the self-sufficiency rate of ethylene feedstock increased by 2.49 percentage points. The C₂⁺ components in FCC and DC dry gas accounts for 67% of the resources to be recovered in the refinery, and ethylene resources are abundant, so it is suggested to give priority to the recovery of FCC and DC dry gas; When the gasoline is surplus, the hydrogenated light naphtha is all used as ethylene feedstock, and when the diesel or kerosene is surplus, the atmospheric first line oil or kerosene is used as ethylene feedstock.