Treatment method of ethylene tar

Abstract

The invention discloses a treatment method of ethylene tar. The method consists of: fractionating ethylene tar into light fraction and heavy fraction, mixing the heavy fraction with a conventional coking raw material, conducting delayed coking to obtain coker gasoline, coker diesel oil and coker gas oil, mixing the coker diesel oil with the ethylene tar light fraction, performing rectification / crystallization purification to obtain naphthalene, mixing the naphthalene removed oil, naphthalene after-cut oil, with the coker gasoline and the coker gas oil, taking the obtained mixture as a hydrotreating raw material, leaving the material to undergo a hydrofining reaction, separating gasoline fraction I, subjecting the obtained fraction heavier than gasoline to hydrocracking so as to obtain gasoline fraction II and a diesel oil product, and mixing the gasoline fraction II with the gasoline fraction I so as to obtain a final gasoline product. Directed at the characteristics of high content of aromatic hydrocarbon, colloid, carbon residue and asphaltene in ethylene tar, the method provided in the invention fractionates the ethylene tar into light fraction and heavy fraction, and adopts different processing processes, thus increasing the added value of ethylene tar. While generating the chemical raw material naphthalene, the method also improves the product quality of light fuel oil, and also enables the equipment to run smoothly for a long period.

Description

technical field [0001] The invention relates to a method for producing clean fuel oil from ethylene tar, in particular to a combined process of delayed coking and hydrogenation for blending ethylene tar. Background technique [0002] The increasing shortage of world oil resources and the increasing price make it necessary for refineries to reduce emissions and increase efficiency. Ethylene tar is currently mainly sold as heavy fuel oil or carbon black raw materials, with low added value. [0003] Ethylene tar is a high-temperature condensation product of ethylene cracking raw materials and products in the steam cracking process. Its initial boiling point is 170-260°C, and its final boiling point is >600°C, generally 600-700°C. It belongs to the heavy fraction range. Ethylene tar is mainly a mixture of double-ring or more fused-ring aromatics, with an aromatic content of more than 90% and a density (20°C) greater than 1.0 g / cm 3 , Low content of impurities such as sulfur ...

AI Technical Summary

Problems solved by technology

This method only utilizes a small proportion of light fractions in ethylene tar, and more than 80% of the ethylene tar fraction has not been effectively treated; at the same time, the hydrorefining conditions it provides cannot handle ethylene with a boiling point higher than 280 ° C. tar fraction

[0006] There are reports on delayed coking of vacuum residue blended with ethylene tar: CN101608132A, "Response Surface Analysis Method Optimizing the Delayed Coking Research of Blending Ethylene Cracking Tar" (see "Petroleum Refining and Chemical Industry" 2009 No. 8 P5- P8. "Research on Blending Daqing Pyrolysis Tar in Delayed Coking Unit" (see "Petroleum Refining and Chemical Industry" 2007, No. 12 P20-P22), "Influence of Blending Ethylene Cracking Heavy Oil on Delayed Coking" (see "Petrochemical Technology and Application" 2010 No. 1 P44-P49) and "Vacuum Residue Blending Ethylene Heavy Tar Cocoking Test" (see "Journal of Maoming University" 2008 No. 1 P7-P9, etc. These studies are all ethylene The whole distillate of tar is blended with vacuum residue as raw material for delayed coking, which will make the yield of liquid and light fuel oil products lower, and the quality of the resulting liquid products—coker gasoline, diesel oil and wax oil remains the same. Poor, needs further processing

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