lignite
Lignite is a low-calorie coal that is imperfectly developed in the state between anthracite and peat. Russia, the United States, Canada, India, Australia and some countries in Europe are mining, which as a power plant fuel applications are more widely in Greece, accounting for 50% of the total fuel plant in Germany, in the United States Accounting for 25%. The world's total reserves of 4 trillion tons of lignite, accounting for 40% of the world's total coal reserves of weak. Lignite color is dark brown, carbon content of 25-35%, moisture content of up to 66%, ash content of 6% -19%. The calorific value of 10-20 kJ / kg lignite contains high volatility, so it is easier to liquefied or gasified. But because it contains more water, and easy to spontaneous combustion, will increase the cost of transportation and storage, so very few in the market circulation. Usually in the vicinity of the construction of power plants in the immediate vicinity of the mine, direct fuel consumption. Lignite power plants have more pollutant emissions than ordinary coal-fired power plants, especially with open-air mines, often causing environmentalists and politicians to disagree. The coal age of lignite is younger than that of ordinary coal and is generally present in the stratigraphic strata. Generally divided into two kinds - wood coal and real lignite. ...