The Coking and Gasification of Coal in Coal Chemical Industry

There are many types of coal chemical equipment, which are mainly divided into two categories: dynamic and static. Among them, hydrogenation reactors, gasifiers, reduction furnaces, heat exchangers, Shengyun vessels and other pressure vessels, pipelines, valves, etc. belong to static equipment, while pumps, fans, compressors, and air separation equipment belong to dynamic equipment.

Gasifier is the most critical equipment in coal chemical industry. Most coal chemical projects need to go through the process of converting coal into syngas through gasifier. Air separation equipment is also one of the key equipment in coal chemical industry. Coal gasification and coal liquefaction both require a large amount of high-purity oxygen and have high technical barriers.

The coal produced in the world is mainly used as fuel for power stations and industrial boilers; a certain proportion is used for coal chemical industry, among which the coking and gasification of coal are the main ones.

In the 1980s, the annual output of coke in the world was about 340Mt, and the annual output of coal tar was about 16Mt (the naphthalene extracted from it was about 1Mt). Coal tar processed products are widely used in the preparation of plastics, dyes, spices, pesticides, medicines, solvents, preservatives, adhesives, rubber, carbon products, etc.

In 1981, the total production of synthetic ammonia in the world was 95.3Mt, mainly from oil and natural gas. Ammonia produced from coal only accounts for about 10%; the proportion of synthetic methanol from coal is also very small, accounting for only about 1% of the total methanol output.

American Coal Chemical Industry

In 1984, the coal used in the United States was 717.7Mt, of which 5.5% was used for coking, reaching 39.5Mt. Benzene, a by-product of coking, accounts for 9% of the total output of benzene, and vinyl acetate produced from calcium carbide acetylene accounts for 8% of its total output. In 1984, the United States built a factory to produce high calorific value city gas by gasification and remethanation of lignite. The daily processing of lignite is 22kt and the gas production is 3.89Mm. At the same time, many new process tests have been carried out in coal gasification and liquefaction.

Federal German Coal Chemical Industry

In 1984, the Federal Republic of Germany used 84.8Mt of coal (excluding lignite), coking coal accounted for 32.6%, which was 27.6Mt, and the annual output of coal tar was about 1.4Mt. The coal tar produced by the coke ovens of iron and steel enterprises across the country is concentrated in five tar processing plants for processing, and more than 500 kinds of chemicals are produced. Calcium carbide acetylene chemical industry has made great progress, and there are still improvements in technology. There are also some new developments in the research of pressurized gasification and direct liquefaction of coal.

Japan Coal Chemical Industry

In 1984, Japan shared 106.9Mt of coal. Due to its well-developed iron and steel industry, the metallurgical coke used in ironmaking and other metallurgical uses is very large. Therefore, coking coal accounts for 66%, which is 70.5Mt. Coal tar production of 2.4Mt per year provides an industrial source of all naphthalene. Vinyl acetate, which is produced from calcium carbide acetylene, accounts for 23% of its total output.

South African Coal Chemical Industry

South Africa is a region that still has indirect coal liquefaction plants in the world. There are three synthetic liquid fuel plants, SASOL-Ⅰ, SASOL-Ⅱ, and SASOL-Ⅲ. The annual coal processing is about 33Mt, and the production of gasoline, diesel, jet fuel and other oil products Millions of tons, and hundreds of thousands of by-products of gaseous hydrocarbons, ethanol, ammonia, sulfur and other chemicals.