Different Types of Coal

Peat coal, lignite coal, Sub-Bituminous coal, Bituminous coal, Semi-Bituminous coal, Semi-Anthracite coal, Anthracite coal and Super Anthracite coal are the different types of coal.

Coal types

Peat Coal:

Peat coal contains high moisture and a small percentage of volatile matter and % of Carbon. It is Wet used in power plant. It has very less heating value of 2393 KJ/Kg.

Lignite Coal:

Lignite coal has fixed carbon moisture content 30 to 45%.
Proper storage is required to spontaneous combustion.
Used in power plants locally. It can not be transported.
woody clay like appearances. Heating value is 13800 to 17585 KJ/Kg.

Sub Bituminous coal

Sub Bituminous coal can be stored carefully.
There is no woody structure.
It is called black ignite.
Moisture content 17 to 20%.
volatile matter 35 to 45%.
Heating value 18840 t0 23000 KJ/Kg.

Bituminous coal:

Bituminous coal has Low moisture percentage.
Low or high Ash percentage
It can be a caking, cooking or free burning coal.
Heating value s 23,000 to 34750 KJ/Kg.

Semi-Bituminous coal:

Semi-bituminous coal has high fixed carbon
Volatile matter 14% to 22%.
Heating value 33,500 to 34,750 KJ/Kg.

Semi Anthracite Coal:

Semi anthracite coal is harder than Bituminous coal
Heating value 33,500 to 34,750 KJ/Kg.
Costly for power generation.

Anthracite coal:

Purest form
High carbon content.
Less heating value
Less ash
Scars
Less calorific value.

Super Anthracite coal:

Heat coal, with shining black surface
A high percentage of Carbon.
Very difficult to ignite.

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