formations of coal

Coal haves different formations. The formations are peat, ligniten bituminous, anthracite, and coke.
Coal is forn=med from the remains of swamp plant from 300-400 million years ago which dead plants and animals become buried in the swamp. Since there was no oxygen the plants didn't rot which formed a peat.

Peat is a slowly decaying plant matter found in bogs moors and muskegs.  Acidic and anaerobic conditions prevent it completely decaying. In most rural aera people of the rural Europe use peat as a heat souce which very low value compared to coal.

 Lignite which sometimes called "brown coal" are found in Alaska and some Western stateshaves low carbon concentration and low heat value.

Bituminous is the most common form of coal. The carbon value is highly variable and heat value ranges from 10,000-15,000 BTU/lb.

 

 

Anthracite is the results from the netamorphosis of bituminous coal. It is the highest carbon content and heat value. Most anthracite comes from Northeastern Pennsylvania. It haves a low smoke and high heat values makes anthracite popular for home heating in the northeastern U.S.

 

Finally coke, coke it when bituminous coal is heated to 2000 in the absence of oxygen. Water tart gas and other volatiles are driven off to leave a high carbon fuel. The by-products of coking are collected for energy production. Cike is primarily used as a heat source in the steel industry.