Development and evaluation of fume free explosives for underground blasting applications

The Challenge

Conventional Ammonium Nitrate (AN)-based explosives represent a substantial source of nitrate release into the environment, and produce undesirable exhaust gases including nitrogen dioxide (NO2), nitric oxide (NO) and carbon monoxide. These pose a substantial hazard to mine workers, particularly in enclosed underground environments.

Hydrogen Peroxide (H2O2)-based explosives could reduce or eliminate these negative effects, but their performance in a mining environment is unproven.

Key Findings

H2O2-based explosive hydrogel proved capable of being loaded and fired in an underground environment and produced detonation and blast performance comparable to AN-based products in early field trials.

The breakdown products of H2O2-based hydrogels are oxygen gas and water vapour. Their use eliminates the release of potentially hazardous NOx and nitrate compounds produced by conventional AN-based explosives.

H2O2 hydrogels also produced lower carbon monoxide (CO) output than conventional AN-based equivalents. The reduced levels of this dangerous gas would reduce corresponding safety concerns and assist miners with operational planning.

Benefit to WA

Adoption of H2O2-based explosive gels will help improve worker safety and lower the cost of mine development in WA’s underground mining industry, especially where H2O2 is already utilised on-site.

Adoption of H2O2-based explosives would also reduce the environmental impact of mining operations in WA through the elimination of nitrate release in blasting and resulting waste products.

Keywords: NOx, fume-free, explosives, hydrogen peroxide, underground mining