Speakers at a technical summit hosted by blasting solutions and mining chemicals company BME illustrated how “clean technology” can help mining companies across Africa meet tougher environmental laws while keeping costs down.

Held at the Council for Scientific and Industrial Research’s Pretoria-based Inter-national Convention Centre, last month, the event sought to renew focus on driving value through innovation, safety, sustainability and responsible mining.

BME global manager strategic partnerships Dr Rakhi Pathak and Hypex Bio CEO Thomas Gustavsson presented different paths to “greener blasting”, with both aiming to show how mining sustainability could be turned into operational value.

BME has long focused on extracting value from what was once considered waste – a consideration highlighted by Pathak, who explained that BME’s manufacture of emulsions from large volumes of used oil is refined to remove impurities before its reuse in emulsions as a core raw material.

The refined oil is blended with emulsifiers, fuels and a dual-salt nitrate solution to create the final product, which is a bulk emulsion explosive that can be pumped at a mine site and charged into blast holes.

“BME uses this emulsion for mechanised and bulk blasting, where it improves fragmentation and lowers nitrogen oxides [NOx],” she said.

However, every batch of used oil differs in quality, resulting in thorough testing of every load in the laboratory before production.

“This careful control ensures consistent product performance and supports a circular-economy approach that reduces hazardous waste while keeping operations efficient,” said Pathak.

Further, product design must match on-the-ground conditions at African mines. This is a challenge, as emulsions using used oil and water, stabilised with emulsifiers, mean that raw-material quality and phased ratios determine the stability and shelf life of the product.

Emissions Tackling

BME’s dual-salt approach also targets harmful emissions, with Pathak noting that BME’s dual-salt emulsions are manufactured at relatively lower temperatures and chemically possess an improved oxygen balance ratio leading to lower NOx fumes.

“This results in less formation of nitrogen oxides after blasting. Dual-salt emulsions offer superior oxygen-balanced blasting solutions,” she said, adding that technical choice is especially valuable in regions where post-blast fumes and nitrate leaching draw scrutiny from regulators and nearby communities.

Case studies helped to prove the concept, with a two-year supply project of 4 000 t of emulsion resulting in the product’s enduring 1 700 km of road travel and sea transport to a remote site.

“The product maintained stability through multiple pumping cycles and wide temperature variations. These operational results show how the right chemistry reduces logistics risk and downtime for African mines that often work under harsh and variable conditions,” added Pathak.