Alternative explosives on the way
AN alternative to ammonium nitrate- based commercial explosives in mining is a step closer, according to Mining3, following a recent detonation performance test of a non- toxic post- blast substitute explosive.
Mining3 had been working with the University of Queensland’s School of Mechanical and Mining Engineering to test the explosive formulation, which replaced the nitrogen component with hydrogen peroxide as the main oxidising agent.
While the ammonium nitrate formulation was considered highly effective, the explosives didn’t always detonate efficiently, which could cause nitrogen oxide fumes to be produced, posing serious health and environmental risks.
By comparison, hydrogen peroxide was a simple compound predominantly made up of water, meaning it was not harmful.
Mining3’ s hydrogen- based gel alternative would be reliant on mechanical sensitisation and influenced by the diameter of the void spaces.
Using the two new physical sensitisation materials based on glass and polystyrene in its formula, Mining3 conducted a series of detonation tests in December 2018, before announcing its results on 24 January.
According to Mining3, the tests delivered improved explosive performance, reliability and product stability.
Mining3 explosives research chemist Andrew Kettle said the researchers had a renewed confidence in the robustness and performance of alternative explosives, superseding chemical gassing techniques.
“We also had the opportunity to manufacture prototype cartridges for packaging the explosive, in preparation for underground mine- site trials proposed for 2019,” Dr Kettle said.
Surface applications would also be trialled in 2019.