Bituminous coal

Coal is a black, hard, solid sedimentary rock that was formed by carbonization of plant residues ( coalification ) and consists of more than 50 percent by weight and more than 70 percent of the volume of carbon. This is a collective term for higher quality coals. The coal is also called black gold. It is a fossil fuel and is used by combustion and the production of coke for the Stahlverhüttung mainly to generate electricity and heat generation. Residues from the combustion are used in the construction industry.

Formation

The origin of the coal lies in a geological period, about 350-250 million years ago. In the Carboniferous and Permian gediehene Urfarne, Calamites and seal and scale trees formed large swamp forests. The optimum growth conditions for the plants have led to severe over-production of biomass that was accumulating in swamps, similar to a recent peat bog. These layers were partially covered periodically by other sediments such as clays and sand, such as by river sediments. Such recurrent, cyclic sedimentation ( Zyklotheme ) are characteristic of the formation of the coal in the Upper Carboniferous and gave rise to several superimposed deposited coal seams. Through the sedimentary cover, the bottom floors were compressed and dewatered and finally emerged over millions of years it through the process of coalification, the coal. Here, the organic starting material under exclusion of air, high pressure and high temperatures was compacted and converted, and there was a strong bond of carbon, water and non-combustible inclusions in the form of ash. Therefore, coal is characterized by a black, solid matrix, can be found in the common plant fossils. The coal occurs mainly in stratabound deposits, the coal seams.

Classification

Coal are after acceptance of volatiles ( gases ) divided into:

Annealed coal or coal ausglühende was called " Zinder " ( masc of ) called ( cf. English "Cinderella" Cinderella ).

Stocks

The world's eligible at current prices and with current technology reserves were ( BGR) estimated in 2006 by the Federal Institute for Geosciences and Natural Resources to 736.1 billion tonnes of coal. Of this total, 29.0 percent ( 213.3 billion tons ) in the U.S., 22.7 percent ( 167 billion tons ) to the People's Republic of China and 13.0 percent ( 95.4 billion tons ) in India. With constant promotion ( 5.356 billion tons in 2006), the demand could be met even for about 137 years.

Of the German coal inventories were up to 2003 around 24 billion tonnes as winnable. Given a current production rate of 23.5 million tonnes ( 2006) would result in a theoretical range of over 1000 years. Owing to unfavorable geological conditions, however, only a portion of these stocks is currently internationally competitive eligible. Therefore representative of the German coal industry figured while maintaining the current production is the range of the German coal to about 400 years. However, BGR has no speculative reserves longer be detected on the grounds that it would, the recoverable at current prices and with current technology stocks in their " Energy Study 2004" by 99 percent to 183 million tonnes in 2005 to 161 million tons and in 2006 to 99 million tonnes ( theoretical range from 2006: four years) reduced.

According to the latest government decisions, the coal production in Germany until 2018 to phase out. This decision should be tested again in 2012 according to the updated cost projections, however, the Federal Government decided on 17 November 2010, this test should be deleted without compensation. In order for the European Union to come to meet, holding a subsidy on competition grounds only until 2014 admissible.

Promotion

Worldwide in 2007 about 5.523 billion tons of bituminous coal were extracted. The People's Republic of China ( 44.9 percent ) and the USA ( 17.5 percent) encourage them almost two-thirds. In Europe, the largest mining areas are located in Russia, Poland and Ukraine. Mining areas in Germany are currently the Ruhr and Ibbenbüren ( anthracite coal). In the Aachen coal mining area, the last mine was closed in 1997. In Saarland, the last mine on 29 June 2012 was shut down.

In Germany is currently mined coal still in four mines of RAG AG German coal. Of these, three in the Ruhr area and one in Münster. Following closure of the mine, the mine Saar Ibbenbüren is currently with 1545 m depth, the deepest German coal mine. The exclusive mining method is the Strebbruchbau. As mining machines of coal plow and the shearers are used. Coal from countries such as Australia, Colombia, the U.S. and South Africa can be promoted cheaper than coal from the domestic market, which is determined by both the deposits and by the wage structure of the country. Thus, the coal can there frequently in surface or by Mountaintop Removal mining are degraded, which is much cheaper than underground mining. This not only coal is converted into electricity from abroad in Germany, at present there the coal subsidy is phased out in 2018.

Source: Federal Institute for Geosciences and Natural Resources

Use

Coal is primarily used as a solid fuel to produce heat by combustion. Of carbon dioxide, water vapor and other gases, such as sulfur dioxide produced. To produce electrical energy, water vapor is generated by the heat, which in turn drives turbine. To compare how much energy can be obtained with which coal, usually one uses the standard coal. A great deal of coal is also used for the extraction of coal coke. Coke is used as fuel and as a reducing agent in iron production in blast furnaces. The coal is also used as a raw material for the chemical industry, this is particularly the accumulating during the coking of coal tar of interest; However, the coal has lost its importance as the main raw material for the chemical industry for the benefit of oil since mid-20th century.

Coal prices

The price of imported coal to German border is ( Federal Office of Economics and Export Control ) determined and published regularly by BAFA. The previous high was in the 3rd quarter of 2008 131.80 € / tce. The previous maximum results for an award of approximately 1.61 euros per kWhth cents. In comparison, a previous maximum crude oil price of 147 $ / barrel (equivalent to 82 euros), the cost per kWhth of about 5.2 euro cents. Lignite is, however, much cheaper, and costs about 40 € / tce. Reported by the power plant operators according to § 6 paragraph 2 of the Law on Financing coal coal from third countries covers and average prices to the German border for power plant coal found in the following table. For a modern coal-fired power plant as the blocks D and E of the Westfalen power plant resulting in a process efficiency of 46 % with the latest table value fuel cost of about 2 cents / kWhe.

Environmental impact

If coal burned, gives rise to various residues. Steam coal contains up to 12% non-combustible solid components, which are referred to as ash content. Together with the proportion of water to form the fiber content, which accounts for about 20%. The exhaust consists mainly of carbon dioxide, in addition of nitrogen oxides and sulfur dioxide can and trace elements and dusts contain. In modern coal-fired power plants are the fumes of sulfur dioxide in flue gas desulfurization systems, cleaned by the catalytic or non-catalytic denitrification of nitrogen oxides and by means of electrostatic precipitator dust (fly ash ). Thus, the greenhouse gas carbon dioxide remains essentially left, which is released into the atmosphere. Coal fly ash is (as well as lignite fly ash ) used as an aggregate in concrete production and inter alia used in the custody of abandoned mines as Verfüllstoff.

Through coal seam fires in near-surface coal seams occur the same exhaust as the combustion in power plants, additionally carbon monoxide due to incomplete combustion. Flözbrände have significant local impact, but can be neglected at a global scale: go to China each year about 25 million tonnes of coal by Flözbrände lost. This corresponds approximately to the German annual promotion, or 1% of China's coal annual production of about 2.5 billion tons.

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