JNTU B.Tech III MINE ENVIRONMENTAL ENGINEERING II Previous Question Paper (March - 2024 - R16)

Mine fires are generally classified into two main categories based on their origin:

1. Exogenous fires: These are fires caused by external sources of ignition, such as friction from conveyor belts, electrical short circuits, welding or cutting operations, or open flames.
2. Endogenous fires: These are fires caused by spontaneous combustion of coal or carbonaceous material within the mine, resulting from the oxidation of coal when exposed to air in goaf areas or abandoned workings.

Spontaneous combustion in mines leads to several critical adverse effects:

• Production of toxic gases: It generates hazardous gases such as carbon monoxide (CO), which is highly toxic and can lead to fatalities, and sulfur dioxide if pyritic materials are present.
• Risk of explosions: The heat generated can lead to the distillation of coal, releasing volatile hydrocarbons that, when mixed with air, create an explosive atmosphere, potentially triggering a mine-wide explosion.
• Loss of coal reserves and equipment: It causes significant loss of valuable coal resources due to oxidation and burning, and can destroy expensive mining machinery and infrastructure, leading to long-term operational shutdowns.