FOSSIL FUELS III

Coal

Should the use of coal in America be expanded?

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0%0%

1. Yes2. No

• Formed from ancient plants.• Coal beds were prehistoric swamps.• Can be considered to be “stored” solar energy.• Photosynthesis:CO2 + H20 + solar energy carbohydrates + O2

We can also run the process backwards and burn carbs to get energy, water and carbondioxide.

• Normally when a plant dies it decomposes.• If there is not enough Oxygen, it can’t

completely decompose, thus we get a slow accumulation of energy.

• In a swamp, the bacteria that decompose the plants also use up the Oxygen.

• Coal found today formed between 1 and 440 million years ago.

• Steps to becoming coal:• Peat• Lignite• Subbituminous• Bituminous• Anthracite

• The major difference is the percentage of the coal that is Carbon. Higher Carbon concentration means better quality coal. (in general)

• Coal progresses through the stages with increase pressure and temperature.

TypeType % Carbon% Carbon Energy Content Energy Content (Btu/lb)(Btu/lb)

LigniteLignite 3030 5000-70005000-7000

SubbituminousSubbituminous 4040 8000-100008000-10000

BituminousBituminous 50-7050-70 11000-1500011000-15000

AnthraciteAnthracite 9090 1400014000

• The largest amount of US coal is Bituminous.• Approximately 1% is Anthracite. (Found in

Pennsylvania.)• Many coal veins have a high sulfur content.– Significant contributor to acid rain.– S+O2SO2

– SO2 combines with water in atmosphere to form sulfuric acid.

– Limits the use of those coals (some progress is being made in technology to use high sulfur coal)

Coal Mining

• Coal veins can be 1in to 400 ft thick.• Must be at least 2 ft thick to make mining

profitable.• Two basic ways to get to it– Tunnels (deep reserves) (40%)– Strip mining (near surface) (60%)

Tunnel MiningTunnel Mining Video

Strip Mining

Mountain Top Removalvideo

Should mountain top removal be removed?

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1. Yes2. No

US Coal Reserves by Type

Coal Reserves Sulfur Content

World Coal Reserves

TOTAL (million tonnes (teragrams)

0 50000 100000 150000 200000 250000

United States

Russia

China

India

Australia

South Africa

Ukraine

Kazakhstan

Poland

Brazil

Proved Coal Reserves (2006)

Coal Production

million tonnes0 1000 2000 3000 4000 5000 6000 7000

China

USA

India

Australia

Russia

South Africa

Germany

Indonesia

Poland

Total World

Production of Coal 2006

A thick shroud of haze lingers over China, turning the sky an opaque grey. Beijing, China's capital, is situated under the densest portion of the smog layer. The aerosol pollution can be seen blowing eastward across the Bo Hai Bay and Yellow Sea reaching as far as North and South Korea and the islands of Japan. (NASA)

Coal Consumption

Mix of Fuels in US

US Coal Production

Expected Life of Reserves0 100 200 300 400 500 600

China

USA

India

Australia

Russia

South Africa

Germany

Indonesia

Poland

Total World

Production of Coal 2006

• Estimated that we have enough reserves for 200-300 years at current production rates.

• Use may be expanded– Replace aging oil/natural gas/nuclear electric

plants– More demand for electrical energy– Alternative uses such as coal gasification.

Coal Gasification

• Coal gasification can be used to produce syngas, a mixture of carbon monoxide (CO) and hydrogen (H2) gas. This syngas can then be converted into transportation fuels like gasoline and diesel. Alternatively, the hydrogen obtained from gasification can be used for various purposes such as powering a hydrogen economy, making ammonia, or upgrading fossil fuels.

Adverse Effects of Coal• Millions of tons of waste products• Acid rain from high sulfur coal• Interference with groundwater• Impact of water use on flows of rivers and consequential impact

on other land-uses• Coal-fired power plants without effective fly ash capture are one

of the largest sources of human-caused background radiation exposure

• Coal-fired power plants shorten nearly 24,000 lives a year in the United States, including 2,800 from lung cancer[44]

• Coal is the largest contributor to the human-made increase of CO2 in the air[46]

Should the use of coal in America be expanded?

1 2

77%

23%

1. Yes2. No