Safety in quarrying is priority No. 1, and it must be prioritized while achieving efficient and effective production.
Accomplishing these objectives can depend on your selection of explosive material for initial rock breakage and removal. Optimized blasting helps achieve ideal rock breakage levels without incurring additional rock crushing costs, enabling operators to achieve cost optimizations throughout their operations.
More importantly, effective and reliable blasting activity enables mining operators to best protect their workforces and the surrounding community.
While ammonium nitrate-fuel oil (ANFO) has been widely used as a bulk explosive in mining and quarrying applications under favorable conditions, other proven alternative options are available that can deliver higher levels of performance. Specifically, emulsion explosives, which take a different physical form than typical ANFO, have shown to deliver water resistance, burning efficiency and safety.
Safety and efficiency
Of course, it’s helpful to understand the basic structure of emulsion explosives and how they contribute to effective blasting.
Emulsion explosives can be broken down into four basic components: ammonium nitrate, water, fuel and the emulsifier. Ammonium nitrate is dissolved in the water; the diesel fuel and the emulsifier coat the water and ammonia nitrate droplets.
Emulsifiers ensure all elements remain mixed and stable for the specified blasting application. The higher quality the emulsifier, the more efficient and stable the emulsion is, enabling the finished emulsion explosive to deliver several end-use performance benefits, including:
■ Effective explosions that help mine operators achieve highly effective rock breakage and mineral retrieval. This can help minimize costs associated with post-blast processes like crushing and material handling. Also, optimized detonations enable tailored blast energy to enhance yield rates.
■ Improved detonation and reaction performance to help avoid toxic NOx emissions that can become detrimental to both the surrounding community, wildlife and the mining operation’s good reputation and back pocket.
■ High levels of product consistency for optimal reliability and repeatable performance that mining operations can depend on.
■ Long-term stability for guaranteed performance every blast. High-performance emulsifiers enable the explosive to remain effectively stable, reducing the risk of crystallization, which leads to performance and safety issues.
Continued innovation
The emulsifier is the only true enabler of the benefits described in this article, but it is important to remember that not all emulsifiers are created equal.
Lesser-quality emulsifiers will not be able to provide the same level of consistency or effectiveness as higher-quality counterparts, and they can lead to inconsistent or less effective explosions.
An extensive range of custom-formulated emulsifiers has been developed to enable efficient uphole blasting underground, improve performance in challenging hot-hole or reactive-ground conditions, and allow the use of low-quality or contaminated oxidizer sources or high levels of used oil. In addition, crosslinker technology to efficiently thicken emulsion explosives and an additive system that enhances the fuel retention of ANFO are examples of non-emulsifier technologies developed to benefit the industry.
It is vital to be educated about high-performance emulsion explosive technologies to promote greater efficiency, effectiveness and safety on the job. Ultimately, service providers should look to partner with tech suppliers who can assist with close product development, research and technical support, as well as compliance with evolving standards and restrictions.
Optimal emulsifier technology is essential in today’s marketplace. Operations depend on it.
Kent Stephens, senior technical manager for specialty emulsifiers, and Shaun Carney, technology development manager for specialty emulsifiers, are with The Lubrizol Corporation.
Related: Explosives engineer details how blasting ‘sets the tone’
