Explosibility Testing of Cotton Gin Dust

Regulations promulgated by the Occupational Safety and Health Administration (OSHA) may require more stringent housekeeping measures in cotton gins. Dust accumulation may be limited to one eighth of an inch or less in an effort to prevent dust explosions similar to those in grain elevators. A commercial laboratory performed an extensive analysis on cotton gin dust and determined the minimum explosive concentration to be 1000 g/m³.  The result will make cotton gins subject to explosible dust regulations and controls.

Tests performed at Texas A&M demonstrated that the same does not explode at any concentration.  The pneumatic conveying and dust abatement systems of a cotton gin were analyzed to determine the possibility of an explosion due to the combustion of gin dust. The mass flow rates for cottonseed, lint, gin trash, and fine dust were estimated for each stage in the ginning process where a possible deflagration could occur at the ginning rates of 20 bph, 40 bph, and 60 bph. Results from the analysis conclude that it would not be feasible for the required minimum explosive concentration to occur within the pneumatic conveying or dust abatement systems of a cotton gin.  The presence of particles larger than 125μm such as cottonseed and lint would act as inhibitors to a gin dust explosion increasing the required minimum explosive concentration.