Method for producing fuel oil by hydrogenation modification of coal tar

Abstract

The invention discloses a method for producing fuel oil through hydrotreating in coal tar, which comprises the following steps: hydrotreating and feeding the coal tar to do pre-hydrotreating reaction and main-hydrotreating reaction after preprocessing coal tar, fractionating hydrogenated oil, and separating out low sulfur and low nitrogen light oil and fuel oil. The method leads a reaction condition to be softer, which inhibits and alleviates the coking process of coal tar hydrogenation material under high temperature with high efficiency, lowers bed layer temperature rising of a reactor, prolongs the service span of pre-hydrogenation catalyst, and assures the operation of longer cycle of the coal tar hydrogenation unit.

Description

1. Technical field: [0001] The invention belongs to the field of fuel chemical industry, and in particular relates to a method for producing fuel oil by hydrogenation and upgrading of coal tar. 2. Background technology: [0002] With the rapid development of the world economy, oil, as a non-renewable natural resource, is decreasing day by day, and its price is constantly rising. Although coal is also a non-renewable natural resource, the world's coal reserves are far more abundant than oil. It is the general trend to use coal as a backup or supplementary energy source for oil. [0003] The utilization of coal resources mainly includes the following types: direct coal combustion, direct coal liquefaction, coal indirect liquefaction and coal coking (including coal gasification). Coal tar is an important by-product obtained in the process of coal dry distillation and gasification, and its output accounts for about 4% of coking coal. In my country, a large part of coal tar is ...

AI Technical Summary

Problems solved by technology

[0004] The existing coal tar hydrogenation technology mainly has the following problems: a. Colloid, asphaltenes, ash and benzene insoluble matter of coal tar raw materials are high, and it is very easy to coke in heat exchangers, reactors and other equipment and pipelines during the hydrogenation process. Unable to achieve continuous industrial production; b. Large heat release during coal tar hydrogenation and upgrading, bed temperature rise is difficult to control, and temperature overshoot is prone to occur

[0005] The applicant proposed a method for producing fuel oil by hydrogenation and upgrading of coal tar in the invention patent application with application number 200610032060.7. Although the method overcomes the above disadvantages, because the coal tar raw material only removes moisture before hydrogenation , ash, and did not remove impurities such as phenols, metals and insolubles, there are still the following problems: the pre-hydrogenation catalyst deactivates quickly, and the pre-hydrogenation temperature is high, which is not conducive to efficiently slowing down and inhibiting coking in the process of coal tar hydrogenation reaction, control the heat of reaction, and realize the continuous operation of coal tar hydrogenation for a longer period