Coal Flashcards
have a brief understanding of most of the content, have an outline of what everything is
Bituminous coal
- dense black and solid
- bright bands of lustre
- 78 - 91% carbon content
- 1.5 - 7% water content
- used for gas making, steam rising and coke making
sub-bituminous coal
- dull black and waxy
- 71 - 77% carbon content
- 10% moisture content
- valuable fuel
coal grades
- peat
- brown coal (lignite)
- black coal (sub bituminous, bituminous and anthracite)
how does coal form
- formed in stagnant swamps with little oxygen
- plant material being partially decayed by defferent bacteria and evenually forming peat
attitude considerations
over 50% support banning new mines - urban residents being more likely along with regional and rural Australians. others thinks its good for Australia’s economy and way of life
underground mining (two main ways)
vertical hole called a shaft being sunk down or sloping tunnel driven from the surface
open-cut mining (procedure)
rocks and soil is broken down with explosives and removed with large mechanical excavators or trucks and shovels. coal is drilled into when exposed and fractured and mined in strips
open-cut mining (benefits)
- employed when coal is closer to the surface
- more economical then underground
- lower accident rates
- less exposure to coal dust
brown coal (lignite)
- formed from peat after exposed to heat and pressure
- dries out and crumbles when exposed to air
- 60% moisture (high)
- high oxygen content
- low heating value
coal extraction process (two main methods)
underground mining and open cut mining
environmental considerations
- removal of massive amounts of top soil leading to erosion, loss of habitat and population
- causes acid mine drainage into ground and water
- release chemicals into environment
underground mining (method 2)
longwall system - two main tunnels cutting into coal seams joined by a 3rd
underground mining (method 1)
room and pillar system - electronically powered machine extracting coal from face and gathered by steel arm into shuttle cars
black coal (+ three distinguish ranks)
formed after greater heat and pressure applied for longer - sub bituminous, bituminous and anthracite
peat
- first stage of coal formation
- develops from partially decomposed plant remains
- either spongy and light brown or dense and black
- 90% water content (reduced to 30% before being burnt)