Reducing the environmental impact of blasting with new explosives
Nitrate in mines’ effluent has the potential to cause long-term environmental damage due to prolonged periods of nitrates being washed out from historical waste dumps. In particular, mines that operate in environmentally sensitive aquatic conditions are invariably concerned about the impact of nitrates and ammonia in their effluent. As a responsible steward of our environment, Orica has developed a holistic management framework and solution to reduce the risk of nitrate leaching resulting from the use of ammonium nitrate-based explosives.
Angus Melbourne, Orica Chief Technology Officer, said: “We are adopting a stronger Environmental Social and Corporate Governance (ESG) position, and one of the ways we are doing that is by focusing on the areas where we have the expertise the make the biggest impact. Given the use of ammonium nitrate bulk explosives carry with it the risk of nitrate leaching into groundwater, our teams have embarked on a project to better understand the causes and risks, and we are proud to have developed a viable solution to enable mines to conduct blast operations without having to compromise on explosive energy which has subsequent downstream cost and productivity impacts on drilling, excavation on mineral processing.”
Identifying Pathways
Orica’s approach to nitrate management includes an established framework to understand nitrate pathways in mining operations and identify the appropriate solution that will minimise nitrate risk. The Nitrate Risk Reduction framework comprises a three-pronged holistic approach that investigates the fundamental mechanisms for nitrate loss at a customer site, benchmarks existing approaches to best practices and recommends solutions to improve nitrate risk management.
James Crough, Orica President of North America, said: “Our approach is both a collaborative and holistic management system that will enable our customers to meet environmental licence limits while eradicating the need for additional materials and processes that typically impact cost, operational productivity, and have their own impacts on the ESG footprint. Our aim is to save time and resources for mining operators.”
Specially Formulated Explosives
Central to the Nitrate Risk Reduction framework is a specially formulated range of Fortis Protect bulk explosives products, developed with the firm’s emulsification technology to deliver the optimal stability and emulsion refinement characteristics into blast holes to minimise nitrate contribution to groundwater and post-blast NOx fumes. The advanced formulation, designed for use in the most arduous wet blast hole applications, is a result of combining advanced surface chemistry with increased viscosity to significantly improve resistance to dynamic water and reduce the risk of nitrate leaching from blast holes.
In addition, technological enhancements to the company’s explosives delivery fleet of MMU (Mobile Manufacturing Units) have been made to further increase the rheology of Fortis Protect products as well as improve the hole loading configuration to reduce the risk of water entrapment in the product during loading.