What are the types of coal
Coal is a kind of solid combustible mineral which is buried in the underground plants and has been formed by the complex biochemical and physical chemical changes.Coal is lignite, bituminous coal, anthracite, semi anthracite, etc..
Bituminous coal: generally granular and small shape, there is powder, black and shiny, delicate texture, containing more than 30% volatile, ignition temperature is not too high, is easy to ignite; carbon content and calorific value of burning high, fast ignition, long flame, there are a lot of black smoke, burning a long time; most of coal are sticky, easy slagging combustion.
Anthracite: there are two kinds of powder and small, black and shiny metal. Fewer impurities, compact, high fixed carbon content, can reach more than 80%; the content of volatile low, below 10%, burning high, fire is not easy; but high heat, slow fire burning up just when the fire is relatively large, strong firepower, short flame and smoke less, long burning time, weak bond when burning, not easy to slag. Should be mixed with appropriate amount of coal to burn, in order to reduce the fire intensity.
