What is fire stopping in mines?
Stoppings or partitions are used in underground mines to separate ventilation airways and ensure that ventilating air goes to the places needed and in the quantities required. These need to be solid and airtight.
What are the preventive measures of coal mining?
3. Methods of preventing and controlling coal seam fire
- 3.1. Detection of fires.
- 3.2. Direct extinguishment of coal seam fire.
- 3.3. Block ventilation leakage.
- 3.4. Injection of inert gases and foams.
- 3.5. Pressure adjustment with positive pressure in part of coal mine.
What are the 3 types of underground coal mines?
There are three major types of underground coal mining: longwall mining, room-and-pillar mining, and retreat mining.
How long do coal miners stay underground?
Miners usually work shifts, and they can be on for 10 days in a row. Some head down before sunrise and return anywhere from seven to 12 hours later.
What is the common cause of fire in coal mine?
The auto oxidation of coal ultimately leads to spontaneous combustion which is the major root cause for the disastrous of coal mine in leading and coal producing countries like USA, China, Australia, India and Germany. It is a slow process and the heat evolved is carried away by air.
How do you stop a mine fire?
Mine fires should be sealed when progress can not be made by fighting them by direct attack, or when other conditions, such as inaccessibility and dangerous conditions, make sealing necessary. In sealing a fire area in metal mines the seals should be placed as close to the fire as possible.
Which factor explains why coal dust is explosive?
Coal dusts are fine powdered form of coal, which are formed by crushing, grinding, or pulverizing of coal. They can be created during mining, transportation, or by mechanically handling coal because of its brittle nature. The surface area of the coal dust explains why it is explosive.
How deep do coal mines go?
Coal that occurs at depths of 55 to 90 m (180 to 300 ft) are usually deep mined, but in some cases surface mining techniques can be used. For example, some western U.S. coal that occur at depths in excess of 60 m (200 ft) are mined by the open pit methods, due to thickness of the seam 20–25 metres (60–90 feet).
What are two methods of coal mining?
Surface mining and deep underground mining are the two basic methods adopted for mining coal. burial, density of the overburden and thickness of the coal seam. occurs at depths of 50 to 100 m are usually deep mined, but in some cases surface mining techniques can be used.
Why we should not sleep in a closed room with burning coal?
Incomplete combustion of coal releases many poisonous gases like carbon monoxide in the environment. This carbon monoxide gas is fatal to health, can lead to coma and even death of the persons sleeping in that room.
What are the risks of underground coal mines?
This is MDG 3 main fans, booster fans and auxiliary fans in underground coal mines Ventilation is a primary risk control. Failure of any ventilation fan presents a major risk factor in the underground environment. At times, ventilation plant may be exposed to high levels of methane and potentially explosive atmospheres.
What are the requirements for sealing abandoned mines?
It includes requirements for seal strength, design, construction, maintenance and repair of seals and monitoring and control of atmospheres behind seals in order to reduce the risk of explosions in abandoned areas of underground mines. It also addresses the level of overpressure for new seals.
How are doors used in underground coal mines?
Sometime doors are used in place of stoppings to allow passage of equipment or personnel where required. Where air routes have to cross, a section of roof or floor is removed and an artificial tunnel constructed to carry return air over (most commonly) or under the intake air.
How to prevent an explosion in a coal mine?
Applying directed water sprays behind the cutting bit to cool and limit the size of the hot streak can prevent these frictional ignitions. How Big is the Problem? From 1986 to 2010, there were 10 multiple fatality explosions in underground coal mines in the U.S.