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Hub AI
Coal dust AI simulator
(@Coal dust_simulator)
Hub AI
Coal dust AI simulator
(@Coal dust_simulator)
Coal dust
Coal dust is a fine-powdered form of coal which is created by the crushing, grinding, or pulverization of coal rock. Because of the brittle nature of coal, coal dust can be created by mining, transporting, or mechanically handling it.
Grinding or pulverizing coal to a dust form before combusting it improves the speed and efficiency of burning, which makes the coal easier to handle. However, coal dust is hazardous to workers if it is suspended in air outside the controlled environment of grinding and combustion equipment. It poses the acute hazard of forming an explosive mixture in air and the chronic hazard of causing pulmonary illness in people who inhale excessive quantities of it.
The distribution of the particle-size of coal dust is frequently measured in mesh. The British slang term for cheap fuel consisting of coal dust (slack) containing small lumps of coal (nuts) is nutty slack.
For use in thermal power plants, coal is ground into dust using a device called a powdered coal mill. The resulting product, called powdered coal or pulverized coal, is then generally used in a fossil fuel power plant for electricity generation. Pulverized coal is a significant dust explosion hazard, as large quantities are suspended in air for transfer from the mill to the power plant. Explosions have occurred[where?][example needed] when the flow drops and flames in the burning chamber pass back along the ductwork delivering fuel.
Coal dust is a fugitive combustible dust - a dust that is both a pollutant and combustible when dispersed into the air. Due to the small particle size and combustible nature of this dust, there is a risk of an explosion and inhalation. The control of coal dust is difficult due to the coal dust being such a fine particle, allowing it to escape and be suspended in the air for a large amount of time.
Coal dust suspended in air is explosive—coal dust has far more surface area per unit weight than lumps of coal, and is more susceptible to spontaneous combustion. However, five elements are needed for an explosion to occur: oxygen, an ignition source, coal dust, dispersion of the coal dust, and confinement of the dust. For instance, a nearly empty coal store is a greater explosion risk than a full one. This is due to the increase of space in the store for oxygen and dispersion to take place.
The worst mining accidents in history have been caused by coal dust explosions, such as the disaster at Senghenydd in South Wales in 1913 in which 439 miners died, the Courrières mine disaster in Northern France which killed 1,099 miners in 1906, the Luisenthal Mine disaster in Germany, which claimed 299 lives in 1962, and the worst: the explosion at Benxihu Colliery, China, which killed 1,549 in 1942. Such accidents were usually initiated by firedamp ignitions, the shock wave of which raised coal dust from the floor of the mine galleries to make an explosive mixture. The problem was investigated by Michael Faraday and Charles Lyell at the colliery at Haswell County Durham of 1844, but their conclusions were ignored at the time.
Inhaling coal dust can cause a number of respiratory diseases. Coal worker's pneumoconiosis, or black lung disease, affects over a tenth of veteran coal miners in the United States (minimum 25 years in the field). Chronic obstructive pulmonary disease (COPD) is another illness seen in coal miners with long term exposure to coal dust. Coal miners in Kentucky, West Virginia, and Virginia contract these particular diseases at an increased rate. This is in part due to a higher amount of silica in the coal dust that is created in Appalachia in comparison to other coal mining sites in the United States.
Coal dust
Coal dust is a fine-powdered form of coal which is created by the crushing, grinding, or pulverization of coal rock. Because of the brittle nature of coal, coal dust can be created by mining, transporting, or mechanically handling it.
Grinding or pulverizing coal to a dust form before combusting it improves the speed and efficiency of burning, which makes the coal easier to handle. However, coal dust is hazardous to workers if it is suspended in air outside the controlled environment of grinding and combustion equipment. It poses the acute hazard of forming an explosive mixture in air and the chronic hazard of causing pulmonary illness in people who inhale excessive quantities of it.
The distribution of the particle-size of coal dust is frequently measured in mesh. The British slang term for cheap fuel consisting of coal dust (slack) containing small lumps of coal (nuts) is nutty slack.
For use in thermal power plants, coal is ground into dust using a device called a powdered coal mill. The resulting product, called powdered coal or pulverized coal, is then generally used in a fossil fuel power plant for electricity generation. Pulverized coal is a significant dust explosion hazard, as large quantities are suspended in air for transfer from the mill to the power plant. Explosions have occurred[where?][example needed] when the flow drops and flames in the burning chamber pass back along the ductwork delivering fuel.
Coal dust is a fugitive combustible dust - a dust that is both a pollutant and combustible when dispersed into the air. Due to the small particle size and combustible nature of this dust, there is a risk of an explosion and inhalation. The control of coal dust is difficult due to the coal dust being such a fine particle, allowing it to escape and be suspended in the air for a large amount of time.
Coal dust suspended in air is explosive—coal dust has far more surface area per unit weight than lumps of coal, and is more susceptible to spontaneous combustion. However, five elements are needed for an explosion to occur: oxygen, an ignition source, coal dust, dispersion of the coal dust, and confinement of the dust. For instance, a nearly empty coal store is a greater explosion risk than a full one. This is due to the increase of space in the store for oxygen and dispersion to take place.
The worst mining accidents in history have been caused by coal dust explosions, such as the disaster at Senghenydd in South Wales in 1913 in which 439 miners died, the Courrières mine disaster in Northern France which killed 1,099 miners in 1906, the Luisenthal Mine disaster in Germany, which claimed 299 lives in 1962, and the worst: the explosion at Benxihu Colliery, China, which killed 1,549 in 1942. Such accidents were usually initiated by firedamp ignitions, the shock wave of which raised coal dust from the floor of the mine galleries to make an explosive mixture. The problem was investigated by Michael Faraday and Charles Lyell at the colliery at Haswell County Durham of 1844, but their conclusions were ignored at the time.
Inhaling coal dust can cause a number of respiratory diseases. Coal worker's pneumoconiosis, or black lung disease, affects over a tenth of veteran coal miners in the United States (minimum 25 years in the field). Chronic obstructive pulmonary disease (COPD) is another illness seen in coal miners with long term exposure to coal dust. Coal miners in Kentucky, West Virginia, and Virginia contract these particular diseases at an increased rate. This is in part due to a higher amount of silica in the coal dust that is created in Appalachia in comparison to other coal mining sites in the United States.