Coal mining is the extraction or removal of coal from the earth by mining. When coal is used for fuel in power generation it is referred to as steaming or thermal coal. Coal that is used to create coke for steel manufacturing is referred to as coking or metallurgical coal. There are two basic methods of mining a coal reserve: surface mining and deep underground mining. The choice of mining method depends primarily on depth of burial and thickness of the coal seam. Seams relatively close to the surface, at depths less than approximately 180 feet (55 m), are usually surface mined. Coal is mined commercially in over 50 countries. Over 7,036 Mt/yr of hard coal is currently produced, a substantial increase over the past 25 years. The world coal deposits are seen in the picture below:
Most of the open pit coal mines are found in the black areas in the map above. The biggest open pit coal mine is the Correjon coal mine near Hato Nuevo In columbia. The output of the mine in 2004 was 24.9 million tons (compared to total global hard coal production of 4,600 million tons). Cerrejón contributes about half of Colombia's coal exports of 52 million tons, with Colombia ranked sixth among major coal exporting nations. The deepest and largest open coal mine in Europe and second largest in the world is the Korkinsk open pit coal mine in Russia. Miles of rails, hundreds of electro trains and giant excavators work in this place.
Not very far from this mine is the 3rd largest coal mine in Kazachstan near Ekibastuz.
All of the Ekibastuz pits were developed for the sole purpose of supplying coal to the Urals and Siberia and with a view to burning it in Kazakhstan to supply electric power to Russia.
Another mine which is also considered one of the biggest in the world is the Hambach mine in West Germany. The hambach mine near the village of Hambach is the biggest Lignite coal mine in Germany. Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad, is the lowest rank of coal and used almost exclusively as fuel for steam-electric power generation. It is brownish-black and has a high inherent moisture content, sometimes as high as 66%, and very high ash (50%) content compared with bituminous coal. It is also a heterogeneous mixture of compounds for which no single structural formula will suffice. To uncover the 2.4 billion tons of brown coal (lignite) found at Hambach, five years were required to remove a 200-m-thick layer of waste sand and to redeposit it off site. The mine currently yields 30 million tons of lignite annually, with annual capacity scheduled to increase to 40 million tons in coming years. The Mine area is over 100 square miles of which 60 are being or have been mined.
Proven reserves will be mined out by 2040 and the resulting crater will be turned into Europe’s 2nd largest lak. The mine also Operates 7 Bucket Wheel Excavators which stands 310 feet tall and are 700 feet long:
Open pit coal mines which also belong to the worlds biggest are: The Black thunder coal mine in Wright in the USA, The Belchatow coal mine in Poland near Belchatow, and the open pit coal mine of Fushun in China.
Tuesday, January 20, 2009