Fine bituminous coal dust is highly explosive when suspended in air. In a typical coal dust explosion, the dust is scoured by a small methane gas explosion, which also provides the initiating flame. … If the initiating explosion is strong enough, even wet coal dust can explode.
What causes coal dust explosions?
Coal mine explosions are generally caused by either methane or coal dust. … Explosions happen when the methane comes in contact with a heat source. The combustion process causes air inside the mine to expand which can create a shock wave. The most common method to control methane levels in coal mines is ventilation.
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 dust explode?
Dust explosions occur when combustible dusts build up in the air and combust rapidly, causing a strong pressure wave to form. They are a deadly hazard in a variety of workplaces, from grain silos to plastics factories. A dust explosion requires several factors to be present at once.
How bad is breathing in coal dust?
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.
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 is there a danger of explosions in coal mines?
There is an increased risk of explosion in enclosed places like coal mines because flammable or combustible materials may become ignited by pressure that have built up inside the mines. Apart from this risk, the mines giving way or collapsing remain possible that could result in several fatalities and injuries.
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.
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.
How explosive is flour dust?
So, can flour explode? As astonishing as it may sound, the fact is that flour dust is more explosive than gunpowder and 35 times more combustible than coal dust. However, it is not explosive in small, non-dispersed quantities.
How do you know if dust is combustible?
OSHA defines combustible dust as “a solid material composed of distinct particles or pieces, regardless of size, shape, or chemical composition, which presents a fire or deflagration hazard when suspended in air or some other oxidizing medium over a range of concentrations.”1 мая 2014 г.
Is Salt a combustible dust?
Supervisors should be notified if proper precautions have not been taken to protect workers from combustible dust hazards. Certain materials in their pure chemical state will not form combustible dust, including cement, gypsum, limestone, sand and salt.
How do I clear my lungs of dust?
Ways to clear the lungs
- Steam therapy. Steam therapy, or steam inhalation, involves inhaling water vapor to open the airways and help the lungs drain mucus. …
- Controlled coughing. …
- Drain mucus from the lungs. …
- Exercise. …
- Green tea. …
- Anti-inflammatory foods. …
- Chest percussion.
How can I clean my lungs?
8 Ways to Cleanse Your Lungs
- Get an air purifier.
- Change air filters.
- Avoid artificial scents.
- Go outdoors.
- Try breathing exercises.
- Practice percussion.
- Change your diet.
- Get more aerobic exercise.
28 мая 2020 г.
Does dust come out of your lungs?
All of these airways are lined by cells. The mucus they produce catches most of the dust particles. Tiny hairs called cilia, covering the walls of the air tubes, move the mucus upward and out into the throat, where it is either coughed up and spat out, or swallowed.