A method for catalytic diesel hydrogenation conversion to aromatics

Abstract

The invention discloses a method for producing aromatics by catalytic diesel hydrogenation conversion, which comprises the following steps: (1) high aromatics catalytic diesel oil is mixed with circulating hydrogen and enters I hydrorefining reaction zone for reaction; (2) the product obtained in step (1) Oil and circulating hydrogen are mixed into II hydrofinishing reaction zone for further reaction, the reaction temperature is 30~120℃ higher than I hydrofinishing reaction zone, and the liquid hourly volume space velocity is 0.2~1.5h lower than I hydrofining reaction zone ‑1 ; (3) The generated oil obtained in step (2) is mixed with circulating hydrogen into the hydrocracking reaction zone for hydrocarbon hydroconversion reaction; (4) The generated oil obtained in step (3) is passed through a separation and fractionation system to obtain gas, light Naphtha, heavy naphtha, diesel fraction, part of the diesel is recycled back to the II hydrorefining reaction zone, and part of the diesel is sent out of the unit; (5) The heavy naphtha fraction obtained in step (4) enters the aromatics extraction system to obtain aromatics products. The method provides a coupled hydrocracking-aromatics extraction process for processing catalytic diesel raw materials, which can effectively increase the production of aromatics.

Description

technical field [0001] The invention relates to the field of petroleum refining. Specifically, it relates to a method for producing aromatics from catalytic diesel oil by coupling hydrocracking-aromatics extraction process. Background technique [0002] Catalytic cracking is currently the most important secondary processing process in the petroleum refining industry, and it is also the core process of lightening heavy oil. As the world's oil becomes increasingly heavy, the processing capacity of the FCC unit is also continuously improved. Using various heavy oils as raw materials, high-octane gasoline, the main product, is obtained through catalytic cracking reactions, and a large amount of sulfur, nitrogen, and aromatics are produced at the same time. Catalytic diesel oil with high content, low cetane number or cetane index, and extremely poor stability. Moreover, the requirements of environmental protection regulations are becoming more and more stringent, and the indica...

AI Technical Summary

Problems solved by technology

On the basis of systematically grasping the influence of operating conditions such as reaction pressure and reaction temperature on aromatics saturation, two different hydrofining reaction zones are set up to solve the problem of single-ring aromatics selection in the conventional hydrofining process of high-aromatic diesel feedstock sex problem

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