轻柴油和加氢尾油共裂解降低柴汽比的技术分析

Technical analysis on co-pyrolysis of light diesel oil and HVGO to reduce the ratio of diesel to gasoline

关键词:  柴汽比  轻柴油  加氢尾油  共裂解  裂解炉标定  低碳烯烃

Key words:  ratio of diesel to gasoline  light diesel oil  HVGO  co-pyrolysis  pyrolyzer calibration  low-carbon olefins

摘要:

降低柴汽比是炼化企业满足市场需求、提质增效、可持续发展的有效措施,轻柴油与加氢尾油共裂解可作为降低柴汽比的重要途径之一。在实验室评价装置上进行轻柴油、加氢尾油的裂解性能试验,并在USC工业裂解炉上进行了不同裂解炉出口温度、混合比例的轻柴油和加氢尾油共裂解标定试验。结果 表明:裂解三烯和C₅&C⁺₅收率总计达到76%以上,轻柴油裂解低碳烯烃收率远低于加氢尾油,但高附加值的裂解C₅&C⁺₅收率高10%～15%；轻柴油和加氢尾油比为2∶5、在COT为835 ℃下共裂解,乙烯、丙烯和三烯的收率分别达到31.48%、15.29%和53.05%；而轻柴油和加氢尾油掺混比例为1∶3、在841 ℃共裂解烯烃收率更高,即轻柴油与加氢尾油共裂解降低柴汽比技术经济合理。 

Abstract:

Reducing the ratio of diesel to gasoline is an effective measure for refining chemical companies to meet market demand, improve quality, increase efficiency, and maintain sustainable development. The co-pyrolysis of light diesel oil and heavy vacuum gas oil(HVGO) can be used as one of the important ways to reduce the ratio of diesel to gasoline. The pyrolysis performance tests of light diesel oil and HVGO were performed in a laboratory pyrolysis evaluation device, and the co-pyrolysis calibration tests of light diesel oil and HVGO with different pyrolysis furnace outlet temperatures and mixing ratios were conducted in the USC industrial pyrolysis furnace. The results showed that the total product yield of low-carbon olefins and C₅ & C⁺₅ was more than 76%. Comparing with HVGO, the yield of low-carbon olefins which were pyrolyzed by light diesel oil was much lower, while the yield of high value-added pyrolysis C₅ & C⁺₅ was higher of 10% to 15%. The yields of ethylene, propylene, and triene by co-pyrolysis of light diesel oil mixed with HVGO (2∶5) were 31.48%, 15.29%, and 53.05% respectively at 835 ℃ of the pyrolysis furnace outlet temperature. The olefins yield of co-pyrolysis of light diesel oil mixed with HVGO by ratio of 1∶3 is higher at 841 ℃. In summary, it is economically reasonable by using co-pyrolysis of light diesel oil and HVGO to reduce the ratio of diesel to gasoline.