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.
What gas is responsible for most of the explosion in coal mines?
What causes explosions in coal mines?
Coal mine explosions are generally caused by either methane or coal dust. Methane gas is a byproduct of coal. It can build up over time in coal mines when there are not enough other types of gases to dilute it to prevent an explosion. … Explosions happen when the methane comes in contact with a heat source.
What gases are present in coal mines?
Methane gas accumulates in “pockets” of the coal and adjacent strata naturally over millions of years and can be released as the coal is mined. As the pockets are penetrated by the mining machinery the gas seeps into the pit where explosive mixtures of methane can form.
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.
Why is coal dust more dangerous than coal?
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.
What is the average lifespan of a coal miner?
The average life expectancy in the coal mines for those starting work at 15 y was found to be 58.91 y and 49.23 y for surface and underground workers respectively. In the coloured/metal mines they were 60.24 y and 56.55 y respectively.
How often do coal miners die?
The yearly average in coal mining decreased to 30 fatalities from 2001-2005, though 60 to 70 miners still die each year in the U.S. coal and non-coal mining industry.
How do coal miners die?
Pneumoconioses (meaning dusty lung) can cause impairment, disability and premature death. The two main types of pneumoconioses that affect miners are coal workers’ pneumoconiosis (CWP), commonly called black lung, and silicosis.
Which gas is the most dangerous?
Which gas is not found in coal?
Coal gas contains a mixture of calorific gases including hydrogen, carbon monoxide, methane, ethylene and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen.
Which gas is known as fire damp?
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.
Why is methane explosive?
Methane explosions occur in mines when a buildup of methane gas, a byproduct of coal, comes into contact with a heat source, and there is not enough air to dilute the gas to levels below its explosion point, said Yi Luo, an associate professor of mining engineering at West Virginia University.
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.