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China’s coal classification **standard (GB5751-86)** divides Chinese coal into 14 major categories. The properties and main uses of each category are as follows: (1) Anthracite is the type of coal with the highest degree of coalification. It has a low volatile content, the highest carbon content, strong luster, high hardness, high density, a high ignition point, no stickiness, and produces no smoke when burned. These types of coal are further divided into 3 subcategories based on their volatile matter content and uses: Anthracite No. 1, with a volatile matter content of 3.5% or less, is suitable for use as carbon materials and other high-carbon materials ； Bituminous coal No. 2, with a volatile matter yield of more than 3.5%–6.5%, is the main raw material for producing synthetic gas ； Bituminous coal No. 3 with a volatile matter yield of over 6.5% can be used as fuel for blast furnace nozzles. All three types of anthracite are good fuels for domestic use. (2) Lean coal is a type of bituminous coal with a high degree of carbonization and the lowest volatiles, being close to anthracite; it is also referred to as semi-anthracite abroad. When burned, this type of coal produces a short flame, but it has a high calorific value. It is non-caking; no gelatinous substances are formed upon heating, and it does not cinder. It is primarily used for power generation or domestic heating purposes. (3) Thin coal is a type of bituminous coal with a higher degree of carbonization and lower volatile matter; when heated, it produces only a small amount of gum, resulting in poor cohesiveness. Its properties lie between those of thin coal and lean coal, and it is mostly used as fuel for power generation or domestic use, with a small portion being utilized in the production of gas fuel. (4) Thin coal is a type of bituminous coal with a higher degree of carbonization and lower volatile matter; when heated, it can produce a certain amount of gum ； When coked from a single type of coal, it produces coke with poor fluidity, low wear resistance, and large particle size. This coke can be used as a raw material in coal blending for coking, as well as as a fuel for domestic use and power generation. (5) Coking coal: A type of bituminous coal with moderate to high degree of carbonization, which can produce gelatinous substances with good thermal stability when heated. Has moderate or high adhesiveness ； When used for coking, a single type of coal can produce coke with good fluidity, large lump size, few cracks, high strength, and excellent wear resistance; it is therefore an excellent coal for coking purposes. (6) Fat coal is a bituminous coal with moderate degree of coalification; when heated to a certain temperature, it produces a large amount of gelatinous substances, giving it strong adhesive properties that allow it to bind together some of the inert substances present in the coal ； When coking is carried out using only bituminous coal, coke with good fluidity can be produced; however, this coke has numerous transverse cracks, and the root portion of the coke features honeycomb structures. As a result, its strength and wear resistance are slightly lower than those of metallurgical coal. It is an important component in coke-making blends, but it should not be used alone. (7) Bituminous coal is a type of smoke coal with a low degree of coalification and a high volatility content; when heated, it produces a certain amount of gum, with cohesive properties ranging from weak to moderate ； When coking is carried out using a single type of coal, the resulting coke is long and fragile, with numerous longitudinal cracks; its strength and wear resistance are both poor. Coking produces large amounts of gas, tar, and other chemical products; it is often used in coal blending for coking, and it is also an excellent raw material for producing distillate gas. (8) 1/3 coking coal: It has a moderate degree of coalification, and its properties lie between those of coking coal, bituminous coal, and gas coal. It is a highly cohesive coal with moderate or high volatile matter; when used alone for coking, it produces coke of high strength, making it an excellent raw material for coking mixtures. (9) Gas-fertilizing coal is a type of bituminous coal with a degree of coalification similar to that of gas coal; it features high volatility and strong cohesion. When used alone for coking, it produces large amounts of gas and gum, but due to the excessive release of gases, it cannot yield coke with high strength. It can be used as a blending component in coking processes or as a raw material for producing dry distillation gas. (10) 1/2 medium-cohesion coal has a lower degree of coalification and a wider range of volatilities; it produces less gum when heated. It represents a transitional type of coal whose cohesion lies between that of gas coal and weak-cohesion coal. Those with slightly better cohesion can be used as raw materials for coking, while those with poorer cohesion can be used as raw materials for gasification or for combustion. China has very little coal resources of this kind. (11) Weakly caking coal: It has a low degree of coalification, a wide range of volatile matter content, and produces very little gelatinous substance when heated; it possesses only weak cohesive properties. Its maceral composition includes a large amount of fibrous and semi-fibrous macerals, and it is mainly used as raw material for gasification and as fuel. (12) Non-sticky coal: This type of coal is formed during the early stages of coal formation as a result of certain oxidation processes; it consists mainly of fibrous components, has a low degree of coalification, and lacks cohesion. It can be used as a raw material for gasification and as fuel. (13) Long-flame coal is a type of bituminous coal with a lower degree of carbonization and the highest volatility; it generally does not coking when heated. It produces a long flame when burning, making it an excellent raw material for gasification and for boilers. (14) Lignite is the type of coal with the lowest degree of coalification. It appears brown to black in color, with a dull or bituminous luster; it can be found in lump form or in a soil-like state. It contains a high amount of internal moisture as well as varying quantities of humic acid. It oxidizes easily when exposed to air, and its calorific value is low. Based on their light transmittance PM, they are further divided into two subcategories: Lignite No. 1 with a light transmittance of 30% or less, and Lignite No. 2 with a light transmittance of 30%-50%. Lignite can generally only be used as fuel, and it can also serve as a raw material for gas production.