EDITED Sources of heat, gas and dust in mines (copy)

SOURCES OF HEAT IN

UNDERGROUND MINES

1. Geothermal Heat

2. Auto-compression of Air

3. Rock Heat

4. Machinery and Equipment

5. Blasting Operations

6. Human Metabolism

Geothermal Heat

Heat from the Earth’s interior.

Auto-compression of Air

As air flows downward, it is compressed by increasing air pressure, raising its temperature.

Rock Heat

Hot surrounding rock transfers heat to ventilating air through conduction and convection.

Machinery and Equipment

Diesel engines, drills, loaders, pumps, and compressors release mechanical and exhaust heat

Blasting Operations

Explosives release large amounts of heat instantly.

Human Metabolism

Miners generate body heat during physical work.

SOURCESOF GASES IN

UNDERGROUND MINES

Blasting Gases

Diesel Exhaust

Strata Gases

Oxidation of Minerals

Spontaneous Combustion

Decomposition of Organic Matter

SOURCES OF DUST IN

UNDERGROUND MINES

Drilling Operations

Blasting

Loading and Hauling

Crushing and Screening

Ore Passes and Chutes

Roadways and Traffic

Blasting Gases

Carbon monoxide (CO)

Nitrogen oxides (NO, NO₂)

Diesel Exhaust

CO, NOx, SO₂, and unburned hydrocarbons.

Strata Gases

Methane (CH₄) in coal mines

Hydrogen sulfide (H₂S) in sulfide deposits

Carbon dioxide (CO₂) from oxidation processes

Oxidation of Minerals

Oxidation of sulfide ores consumes oxygen and produces gases.

Spontaneous Combustion

Coal or sulfide materials generate CO and heat.

Decomposition of Organic Matter

Produces methane and CO₂ in some mines.

 Drilling Operations

Major source of fine respirable dust.

 Blasting

Produces fine rock dust suspended in air.

Loading and Hauling

Fragmented rock creates dust during handling and transport.

Crushing and Screening

Mechanical breakage of ore generates large dust volumes.

 Ore Passes and Chutes

Falling material produces airborne dust.

 Roadways and Traffic

Vehicle movement resuspends settled dust.