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 world-wide 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

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.

1) Lignite

– Lowest level (quality) of coal

– Soft, brownish

– Can still see texture of original wood

– Largest portion of the world’s coal reserves

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 ProductsMiscellaneous

Products insecticides fuel carbolic acidfungicides gas fire proofingmoth balls carbon dioxide food preservatives

paint thinner soda water billiard ballsbatteries acetylene medicines

wood preservative synthetic rubber perfumes

disinfectantcharcoal

briquettes ammonia

varnish artificial silk baking powder

insulationrubber cement

fertilizerpaint pigments

sulfurTNT explosive

linoleumsugar substitute

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

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