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coal. What is coal. Coal deposits come from many epochs, but the best and most abundant are from the forests in the warm, swampy river deltas of the Carboniferous period, some 320 million years ago.
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What is coal • Coal deposits come from many epochs, but the best and most abundant are from the forests in the warm, swampy river deltas of the Carboniferous period, some 320 million years ago
Coal is our most abundant fossil fuel resource. Coal is a complex mixture of organic chemical substances containing carbon, hydrogen and oxygen in chemical combination, together with smaller amounts of nitrogen and sulfur. This organic part of coal has associated with it various amounts of moisture and minerals.
Coalification is the name given to the development of the series of substances known as peat, lignite or brown coal, sub-bituminous coal, bituminous coal, and anthracite. The degree of coalification, also called the rank of the coal, increases progressively from lignite to low rank coal, to high rank coal, to anthracite.
The carbon content increases, while the oxygen and hydrogen contents decrease throughout the series. The hardness increases, while the reactivity decreases. Different amounts of heat and pressure during the geochemical stage of coal development cause these differences in rank. It is not due to the kind of plants the coal is formed from.
Coals in the US range from lignite with approximate as-mined carbon content of 30%, volatile matter 27%, and heating value of 7,000 Btu per pound, to anthracite with an average of 85% carbon, 5% volatile matter, and heating value of 12,750 Btu per pound. Sub-bituminous and bituminous coals are intermediate between these values
Uses of coal • Most coal mined in the United States is burned to make electricity. Most people do not realize that when they use electricity, they are probably also using coal. Of the coal that is not used to make electricity, most is used to make steam for heating, as coke in steel making, or is exported. In developing countries half the world's population depends on coal for heat.
Advantages of coal • Coal is one of the most abundant sources of energy, more so than oil and natural gas • Coal is inexpensive when compared to other fossil fuels (or alternative energy sources) • Coal is versatile enough to be used for recreational activities such as BBQ’s or simply for home fires • Burning coal can produce useful by-products that can be used for other industries or products
Advantages of coal • Electricity produced from coal is reliable • Coal can be safely stored and can be drawn upon to create energy in time of emergency • Coal based power is not dependent on weather which cannot be said for alternative forms of renewable energy such as wind or solar power • Transporting coal does not require the upkeep of high-pressure pipelines and there is no requirement for extra security when transporting coal
Advantages of coal • Using coal reduces the dependence on using oil, which is often found in nations where there is unstable political regimes
Disadvantages of coal • Burning coal emits harmful waste such as carbon dioxide, sulphur dioxide, nitrogen oxides, sulphuric acids, arsenic and ash. It also emits twice as much carbon dioxide when compared with natural gas to produce the same level of heat, which increased the levels of harmful greenhouse gases emitted into the earth’s atmosphere. Carbon dioxide emissions from the burning of fossil fuels now account for about 65 per cent of the extra carbon dioxide in our atmosphere. • The burning of coal by large-scale factories to power industry has led to acid rain in some regions
Disadvantages of coal • Coal can be cleaned and/or turned into a liquid of gas but this technology has yet to be fully developed and adds to the expense of creating fuel via coal • Coal mining can scar the landscape and the equipment used for mining is large and noisy which may affect local wildlife
Disadvantages of coal • Transporting coal can be problematic because it requires an extensive transportation system and can also cause additional pollution in the form of emissions from transportation vehicles such as lorries, etc • There are limited stocks of coal remaining – they will be entirely depleted this millennium if we continue to burn coal in the future at the same rate we are today coal can be considered as a non-renewable energy source • The mining industry can cause health difficulties for miners and fatalities due to the potentially dangerous nature of the work • Burning dirty coal can create significant pollution problems
coal • Coal formation http://www.youtube.com/watch?v=MBeXRRTGjNE • How Do They Do It__ Coal Mining Video.flv http://www.youtube.com/watch?v=ylkdUuNOJzw • Take a Virtual Tour of Black Thunder Coal Mine http://www.youtube.com/watch?v=2LQwxTm94Ps