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

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&C₅⁺ 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&C₅⁺ 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.