The Three Main Types Of Coal in Our Country

 The Chinese National Standard for Coal Classification GB/T5751-2009 categorizes coal in China into three major types: anthracite, bituminous coal, and lignite, with a total of 29 subcategories.

 The classification of coal is based on the degree of coalification, dry ash-free volatile matter, and other indicators. The specific categories are as follows:

 Brown coal: Brown coal is the lowest grade of coal in terms of coalification, typically appearing brown in color with a dull luster, and contains a high level of inherent moisture and varying amounts of humic acid. According to the dry ash-free volatile matter Vdaf = 10% as the dividing value between bituminous coal and anthracite, coal with a value less than this is classified as anthracite, and coal with a value greater than this is classified as bituminous coal. Brown coal is divided into 2 subcategories.

 Bituminous coal: Bituminous coal is coal with a degree of coalification higher than that of lignite but lower than that of anthracite. Its characteristic is a wide range of volatile matter yield, ranging from non-caking to strong caking when used for coking alone, and it produces smoke when burned. Bituminous coal is divided into 12 coal categories and 24 subcategories.

 Anthracite: Anthracite is a highly carbonized coal with low volatile matter, high density, high ignition point, and no caking properties; it generally does not produce smoke when burned. Anthracite coal is divided into 3 subcategories.