- Author
-
Nagy, J.
|
Portman, W. M.
- Title
- Explosibility of Coal Dust in an Atmosphere Containing a Low Percentage of Methane.
- Coporate
- Bureau of Mines, Pittsburgh, PA
- Report
-
Report of Investigations 5815,
1961,
20 p.
- Keywords
-
coal dusts
|
methane
|
explosions
|
coal mines
|
safety
|
pressure
|
pressure rise
- Identifiers
- pressures and rates of pressure rise from explosion of the coal dust-methane mixtures; effect of initial pressure on explosion pressure and rate of pressure rise; effect of convection currents on explosion pressure and rate of pressure rise; effect of methane on the minimum dust explosive concentration
- Abstract
- The effect of low percentages of methane (0 to 5 pct.) in an air atmosphere on spark initiated explosions of coal dust was investigated. With low dust concentrations (0.1 to 0.4 oz./cu. ft.), small amounts of methane increase the explosion pressure; with larger dust concentrations (0.5 to 2.0 oz./cu. ft.), small amounts of methane decrease the explosion pressure. The rate of pressure rise of a coal dust explosion increases with increase in methane concentration; about 3 to 4 pct. further addition of methane yields a decrease in the rate of pressure rise. Convection currents created by the air or gas blast used to disperse dust produce an increase in explosion pressure and rate of pressure rise. The minimum explosive concentration of the coal dust decreases about linearly as the concentration of methane increases from 0 to 5 pct. The explosion pressure increases linearly as the initial pressure within the chamber increases. Similarities between coal dust and methane explosions are indicated.