COAL
Kentucky’s Black Gold
Anatomy of Coal
• Solid formed from plants that lived between 300
– 400 million years ago.
• Mostly carbon
• Small amounts of sulfur
• Trace amounts of mercury
• Trace amounts of radioactive materials
• Burning coal releases these materials into the air;
which then are returned to the earth as
secondary pollutants when it rains.
Coal Over Geologic
Time
• Although coal has been
discovered in rocks as old as the
Precambrian Era, most coal
dates from the Devonian Period
(some 400 million years ago.
• As the geologic time scale
shows, the two major worldwide coal forming periods were
the Pennsylvanian (320 to 286
mya) and the Paleocene to Early
Eocene (66 to 52 mya).
• In the United States, eastern
coals are of Pennsylvanian age
whereas western coals are
Paleocene to Early Eocene in
age.
Formation of Coal
• The formation of coal goes in this order:
Peat.… Lignite ….. Bituminous coal….. Anthracite
• The anatomy of a coal forming swamp looks
like this:
Four “Ranks” of Coal
1) Lignite
– Lowest level (quality) of
coal
– Soft, brownish
– Can still see texture of
original wood
– Largest portion of the
world’s coal reserves
2) Sub-bituminous
– Second lowest in quality
– Gives off a little more
energy (heat) than lignite
– US reserves are mostly in
Montana, Wyoming and a
few other western states.
Ranks of Coal (cont.)
3) Bituminous
– Also called “soft coal”
– Gives off more energy
than sub-bituminous coal
– Found primarily in Ohio,
Illinois and in the
Appalachian mountain
range from Kentucky to
Pennsylvania
4) Anthracite
– Hardest coal and gives off
a great amount of heat
– US reserves are located
primarily in Pennsylvania
– Unfortunately, there is
little anthracite coal to be
mined in the US and
elsewhere in the world
Ranks of Coal and BTUs
US Coal Fields
Coal Fields of the World
Stats
• Coal reserves in the US, Russia, and China
could last hundreds to over a thousand years.
• The US has 27% of the world’s proven coal
reserves, followed by Russia (17%), and China
(13%).
• In 2005, China and the US accounted for 53%
of the global coal consumption.
Interesting Facts
• Coal is burned in power plants to produce
– 62% of the world’s electricity.
– 50% of US electricity
– 3/4th of the world’s steel
• A new coal-fired power plant goes on-line
every 2 weeks.
Other Uses of Coal
Products made from Coal
Coal Tar Products
Coke Products
insecticides
fungicides
moth balls
paint thinner
batteries
wood preservative
fuel
gas
carbon dioxide
soda water
acetylene
synthetic rubber
charcoal
briquettes
artificial silk
disinfectant
varnish
insulation
Miscellaneous
Products
carbolic acid
fire proofing
food preservatives
billiard balls
medicines
perfumes
ammonia
baking powder
rubber cement
fertilizer
paint pigments
sulfur
Coal
• Coal is the most abundant
fossil fuel, but compared to
oil and natural gas it is not
as versatile, has a high
environmental impact, and
releases much more CO2
into the troposphere
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Legislation – Reclamation Laws
Clean Air Act
Clean Water Act
National Environmental Policy Act
American Indian Religious Freedom Act of 1978
Antiquities Act of 1906
Archeological Historical Preservation Act of 1974
Bald Eagle Preservation Act of 1969
Endangered Species Act of 1963
Fish and Wildlife Coordination Act of 1934
Forest and Rangeland Resources Planning Act of 1974
Historic Preservation Act of 1966
Migratory Bird Treaty Act of 1918
Mining and Minerals Policy Act of 1970
Multiple Use-Sustained Yield /Act of 1960
National Forests Management act of 1976
National Trails System Act
Noise Control Act of 1976
Resource Conservation and Recovery Act
Safe Drinking Water Act of 1974
Soil and Water Resources Conservation Act of 1977
Wild and Scenic Rivers Act
Wilderness Act of 1964
Plus numerous state and local Acts and Laws, Procedures and Policies.
Clean Coal Technologies
• Coal benefication – term for cleaning coal
• “Scrubbers” – devices that “scrub” the sulfur
out of the gases released by coal-burning
boilers.
– Required in all power plants built after 1978.
– Most scrubbers use limestone to absorb the sulfur
gases.
Coal Cleaning Processes
1. Physical cleaning – coal is crushed and
washed; removes dirt, rocks and inorganic
sulfur and iron.
2. Chemical cleaning – coal is submerged in a
chemical bath to remove sulfur and nitrogen;
very expensive.
3. Biological cleaning – involves using bacteria,
fungi and/or enzymes that literally “eat” the
sulfur out of the coal.
Future of Coal
• Synthetic fuels (synfuels)
– liquid fuels derived
from coal.
• Coal gasification –
converts coal into
synthetic natural gas (SNG
or syngas); removes
sulfur, nitrogen and
particulates before fuel is
burned.
Advantages
• Can be transported by
pipeline
• More versatile than coal
• Burns more cleanly
Disadvantages
• Adds more carbon dioxide
to the troposphere
• Very expensive