1. Peat: A brown deposit resembling soil, formed by the partial
decomposition of vegetable matter in the wet acidic conditions.
Lignite:A soft brownish coal showing traces of plant structure,
intermediate between bituminous coal and peat.
Lignite is high in volatile matter and ash content and low in fixed carbon.
Its calorific value is about 3190 to 3850 kcal/kg.
2. Sub- Bituminous coal: Its known as brown coal also contain
woody materials.
Its caloric value is 4675 to 5775 kcal/kg.
Bituminous coal: This coal is dark gray to black , shiny , hard,
britle ,and denser than lignite and sub – bituminous coal.
3. Anthracite coal: This is hardest of all coal and has black color and
dull to brilliant or sub- metallic lusture .
Coal: A combustible black or dark brown rock consisting chiefly of
carbonized plant matter, found mainly in underground seams and used
as fuel.
6. Volume conversion from peat to coal:
By the time a layer of it has been converted to bituminous coal , it
thickness has been reduced by 90 % ( 100 meter of peat will be reduced
to 10 meter of bituminous coal) and the proportion of carbon raised by
60 to 80 percent.
Due to the increase of carbon percentage the heat generating capacity
of coal increases with higher ranks.
8. Barapukuria coal field : Barapukuria coal mine is an
underground coal mine at Barapukuria in the Dinajpur
District in Bangladesh.
Mining method: Under ground coal mining method.( long wall
mining method )
Coal finding sequence : Gondwana Sequence
9. Coal Reserved:
The barapukuria coal deposit has a proved area of approximately 5.25 sq
km . The reserve coal of barapukuria 390 million ton.
The contract and construction:
In 1994, the Bangladesh government entered into a contract, with the
chines operator CMC ( china national machinery import and export
corporation) for the development of barapukuria underground coal
mine.
10. Seam of barapukuria coal field: There are seven seam of
barapukuria coal field –
11. The mining area and long wall coal faces:
The barapukuria coal field divided into three units :
A northern area ( 271 hectare)
A central area ( 300 hectare )
And a southern area ( 81 hectare )
Coal faces were designed for under ground mining only in the central
area of the coal field.
12. Production and Uses:
The small scale production of coal from the mine started from april 2002
with the extraction of coal for making roadway through the coal seam.
By june 2005, a total of about 91,000+87,000 tons of coal was
produced.
Total production from first seam ( 2005 – 2011) = 3.65 million ton
13. Environmental effect – Land subsidence:
o Major impact on agricultural land with high density population.
o Water and air pollution.
o Toxic released ( dust, gas, drainage).
