In most cases, dust explosions are first initiated by methane explosions. The pressure wave or wind forces created by a small methane explosion can scour the mine entry, blowing coal dust up into the air.
Why is coal dust explosive?
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. As a result, a nearly empty coal store is a greater explosion risk than a full one.
How do you stop coal dust explosions?
Coal dust explosions in underground coal mines are prevented by generous application of rock dust (usually limestone). If an explosion should occur, the rock dust disperses, mixes with the coal dust and prevents flame propagation by acting as a thermal inhibitor or heat sink.
Does coal explode?
Mine explosions can also be triggered when fine particles of coal dust come into contact with a source of heat. While methane is easier to ignite, the explosion pressure and heat value of methane is not as high as coal dust. In most cases, dust explosions are first caused by methane explosions, said Luo.
Is coal dust bad?
1. Exposure to coal mine dust causes various pulmonary diseases, including coal workers’ pneumoconiosis (CWP) and chronic obstructive pulmonary disease (COPD). 2. Coal miners are also exposed to crystalline silica dust, which causes silicosis, COPD, and other diseases.
Can you burn coal dust?
The dust, can be, laid on a fire, once it has been burning for a while. A little at a time, can keep the fire burning, without having to keep putting lumps on.
What disease do coal miners get?
The two main types of pneumoconioses that affect miners are coal workers’ pneumoconiosis (CWP), commonly called black lung, and silicosis. CWP is associated with coal mining, but silicosis can affect workers in many types of mines and quarries, including coal mines.
Why there is much more mine dust than normal dust?
Dusts have a very large surface area compared to their mass. … This greatly-increased surface area allows the material to burn much faster, and the extremely small mass of each particle allows them to catch on fire with much less energy than the bulk material, as there is no heat loss to conduction within the material.
Which gas causes explosion in coal mine?
There are two main types of coalmine explosions: methane and coal dust. Methane explosions occur when a buildup of methane gas contacts a heat source and there is not enough air to dilute the gas level below its explosion point.
How does removing the overburden during coal extraction affect the environment?
Strip mining eliminates existing vegetation and alters the soil profile, or the natural soil layers. Mining disturbs and may even destroy the beneficial micro-organisms in the topsoil. Soil also may be damaged if reclamation operations mix the topsoil with subsoils, diluting matter in the surface soil.
What is left after coal?
Coal ash is the powdery substance that remains after burning coal. … The sludge, which is created from solutions sprayed inside exhaust stacks to capture the harmful chemicals that cause acid rain, sulfur dioxide and nitrogen oxide, falls to the bottom.
What is Coal made of?
Coal is formed when dead plant matter submerged in swamp environments is subjected to the geological forces of heat and pressure over hundreds of millions of years. Over time, the plant matter transforms from moist, low-carbon peat, to coal, an energy- and carbon-dense black or brownish-black sedimentary rock.
How do you bind coal dust?
Charcoal is a material without plasticity, and charcoal dust cannot hold shape without adding a binding material. The best binder has proven to be starch. Any starch will do, but cassava is preferred. Cassava starch is preferred because cassava tuber and chips are very cheap.
How does Black Lung kill you?
Black lung leads to poor health, permanent disability, and death. Because black lung damages the lungs, it causes the heart to work much harder. As a result, a miner with black lung may die from respiratory failure or heart failure.
Is Black Lung curable?
There is no cure for black lung disease – we can only treat symptoms. Medications, such as inhaled steroids, can help patients breathe more easily. More severe cases can require oxygen and possibly lung transplants.
Is Coal bad for your lungs?
In addition, respirable crystalline silica in coal ash can also lodge in the lungs and cause silicosis or scarring of lung tissue, which can result in disabling and sometimes fatal lung disease and cancer.