Under certain temperature and pressure conditions, the coal is thermally processed with a gasifying agent to convert the coal into a combustible gas. At present, there are four types of industrialized gasification: fixed bed gasification (including atmospheric pressure, pressurization, solid-state ash discharge and liquid ash discharge), fluidized bed gasification (normal pressure and pressure), and entrained flow gasification ( Atmospheric pressure and pressure) and molten bed gasification (normal pressure). Classification according to different gasification media, including the following: (1) The gas produced by the fixed-bed coal gasifier with air gas as the gasification medium has a low calorific value. Water gas: A technique in which water vapor is added to an air blast to produce a mixed producer gas to supply a raw material gas for producing ammonia and methanol. (2) Coal hydrogenation In order to increase the methane content in the gas, hydrogen gas is used as a gasification medium under pressurized conditions, which strengthens the gasification furnace production capacity and simplifies the gas purification step. 2. Liquefaction Coal conversion technology for producing clean liquid fuels and chemical raw materials from solid coal. Can be divided into direct liquefaction, indirect liquefaction two categories. Several methods have been developed for direct liquefaction. The well-known processes include solvent refined oil method (SRC-1, SRC-2), hydrogen supply solvent method (EOS), and hydrogen coal method. Indirect liquefaction includes the Mobil process, which converts methanol to high-quality gasoline, and the one- and two-stage process technologies for synthesizing gasoline from syngas. Liquefaction technology is still in the research and experimental stage in China. 3. Coking Using coal as raw material, coke is produced by high-temperature dry distillation, coal gas and coal tar are obtained at the same time, and coal conversion technology of other chemical products is recovered. The main products of coking coke for blast furnace ironmaking, can also be used for casting non-ferrous metal smelting, preparation of calcium carbide, carbon disulfide, elemental phosphorus. The second product is coal tar, which is a raw material for the pharmaceutical, dye and explosive industries after separation and purification by the industrial sector. Coke oven gas and chemical products such as ammonia, benzene, sulfur and thiocyanate are products in the gas purification process. The purified gas is meso-heat value gas, and the calorific value is about 17 500 MJ/m3. Gas 300-400m3 is a gaseous fuel for the steel industry. It can also produce hydrogen and methane after separation. Nissan Turbocharger Core,Nissan Turbocharger Cartridge,Nissan Chra,Nissan Core Assembly Fengcheng Fire Turbocharger Manufacturing Co; Ltd. , https://www.fireturbolader.com
Coal conversion technology
Gasification