Method for removing metal from coal tar at low pressure

Abstract

The invention discloses a method for removing metal from coal tar at low pressure, which mainly solves the problem that the content of metal in all fraction of coal tar is generally higher than 200mu g / g, which highly restricts the operational cycle of a main hydrogenation unit. The method comprises steps of firstly mixing coal tar with hydrogen; then allowing the mixture to enter a fixed bed hydrogenation reactor from the top for hydrorefining reaction, wherein the fixed bed hydrogenation reactor is at least filled with a hydrogenation protective catalyst, which comprises a first protective catalyst, a second protective catalyst and a third protective catalyst which are sequentially filled from top to bottom, the reaction pressure for hydrorefining reaction is 2.8-8.5MPa; then carrying out gas-liquid separation on effluent of the fixed bed hydrogenation reactor so as to obtain the refined coal tar containing less than 2mu g / g of total metal. According to the method, the reaction is carried out at lower operation pressure, and the refined coal tar containing less than 2mu g / g of total metal is produced through hydrogenation at low pressure.

Description

technical field [0001] The invention relates to a hydrogenation pretreatment technology for coal tar, in particular to a method for low-pressure demetallization of coal tar. Background technique [0002] Coal tar is an organic mixture mainly of aromatic hydrocarbons. It is an important by-product of coking industry and coal gasification industry. It can be processed into various chemicals and high-quality fuel oil. With the continuous in-depth development of my country's economic construction, especially the iron and steel industry, the coking industry has also developed rapidly. my country has now developed into the world's largest producer of coke and coal tar. By the end of 2012, the national coal tar production has exceeded 25 million tons per year. With the development of the coal coking industry, the production of coal tar is increasing continuously. However, the actual deep processing of coal tar is less than 8 million tons per year, which is a serious waste of resour...

AI Technical Summary

Problems solved by technology

The existing technical means is to use coal tar as raw material to produce clean fuel oil by hydrogenation process, which not only meets the requirements of the country's policies on developing new energy sources and protecting the environment, but also brings good economic benefits to enterprises. However, coal tar The metal content in the whole fraction is very high, usually higher than 200μg / g, which seriously restricts the operation cycle of the main hydrogenation unit