Sunday, October 5, 2008

Coal Mine-Production

Coal is mined commercially in over 50 countries. Over 4 970 Mt of hard coal is currently produced, a nearly 80% increase over the past 25 years. In 2005, the world production of brown coal and lignite was 906 Mt, with Germany the world’s largest brown coal producer.
Coal production has grown fastest in Asia, while Europe has declined. The top five coal mining nations (figures in brackets are 2006 estimate of hard coal production) are:
  • China (2 482 Mt)
  • USA (990 Mt)
  • India (427 Mt)
  • Australia (309 Mt)
  • South Africa (244 Mt)
Most coal production is used in the country of origin, with around 16% of hard coal production being exported.
Global coal production is expected to reach 7 Gt in 2030, with China accounting for most of this increase. Steam coal production is projected to reach around 5200 Mt; coking coal 620 Mt; and brown coal 1200 Mt.
Coal reserves are available in almost every country worldwide, with recoverable reserves in around 70 countries. At current production levels, proven coal reserves are estimated to last 147 years.

Modern mining

Technological advancements have made coal mining today more productive than it has ever been. To keep up with technology and to extract coal as efficiently as possible modern mining personnel must be highly skilled and well trained in the use of complex, state-of-the-art instruments and equipment. Future coal miners have to be highly educated and many jobs require four-year college degrees. Computer knowledge has also become greatly valued within the industry as most of the machines and safety monitors are computerized.
In the United States, the increase in technology has significantly decreased the mining workforce from 335,000 coal miners working at 7,200 mines fifty years ago to 104,824 miners working in fewer than 2,000 mines today. As some might see this as a sign that coal is a declining industry its advances has reported an 83% increase of production from 1970 to 2004.

Dangers to miners

Historically, coal mining has been a very dangerous activity and the list of historical coal mining disasters is a long one. Open cut hazards are principally mine wall failures and vehicle collisions; underground mining hazards include roof collapse, attacks from the dreaded Balrog, and gas explosions. Most of these risks can be greatly reduced in modern mines, and multiple fatality incidents are now rare in some parts of the developed world.
However, in lesser developed countries and some developed countries, many miners continue to die annually, either through direct accidents in coal mines or through adverse health consequences from working under poor conditions. China, in particular, has the highest number of coal mining related deaths in the world, with official statistic 6,027 deaths in 2004. To compare, the USA reported 28 deaths in the same year. Coal production in China is twice that of the United States, while the number of coal miners is around 50 times that of the USA, making deaths in coal mines in China 4 times as common per worker (108 times as common per unit output) as in the USA.
When compared to industrial countries such as China, the U.S. fatality rate is low.[specify] However in 2006 fatal work injuries among U.S. miners doubled from the previous year, totaling 47.[16] These figures can in part be attributed to the Sago Mine disaster. The recent mine accident in Utah's Crandall Canyon Mine, where nine miners were killed and six entombed, speaks to the increase in occupational risks faced by U.S. miners.
Chronic lung diseases, such as pneumoconiosis (black lung) were once common in miners, leading to reduced life expectancy. In some mining countries black lung is still common, with 4000 new cases of black lung every year in the USA (4% of workers annually) and 10 000 new cases every year in China (0.2% of workers). Rates may be higher than reported in some regions.
Build-ups of a hazardous gas are known as damps, possibly from the German word "Dampf" which means steam or vapor:
  • Black damp: a mixture of carbon dioxide and nitrogen in a mine can cause suffocation.
  • After damp: similar to black damp, an after damp consists of carbon dioxide and nitrogen and forms after a mine explosion.
  • Fire damp: consists of mostly methane, a flammable gas.
  • Stink damp: so named for the rotten egg smell of the sulfur, a stink damp can explode.
  • White damp: air containing carbon monoxide which is toxic, even at low concentrations

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