In response to the complex safety and operational challenges posed by various mining applications, South African explosives and chemicals company AECI Mining Explosives has launched the Powergel X² – a specialised emulsion explosive formulated to handle reactive ground and hot-hole conditions.

Hot holes are those that have been drilled, with an in-hole ambient temperature of 40 ^oC or more. Holes in which the temperature increases by 3 ^oC or more after drilling are also considered to be hot-holes.

According to explosives manufacturers and suppliers association Australian Explosives Industry Safety Group, four main ground conditions are applicable when discussing issues of elevated temperatures and reactive ground.

Previously, the majority of mining operations would take place in areas where either reactive ground or hot-holes existed.  However, in order to extend the life of the mine, operations need to take place in areas where both conditions exist. 

The Powergel X² product was developed for the Southern Africa market to be used in the most extreme blasting conditions, where both reactive ground and hot-holes exist. It is designed to enhance safety and efficiency in surface mining operations by enabling customers to mine in previously unexploited areas.

According to AECI Mining research and technology manager for explosives, emulsifiers, coating and process additives Cheryl Kelly, AECI Mining developed a proprietary test that allows for accurate simulation of hot-hole conditions.

This was developed over several months of testing and the use of data analysis enabled further refinement of the test methodology, ultimately enabling the department to test and evaluate various emulsion explosive formulations to fully understand the impact each component of the formulation has on the behaviour at these extreme temperatures.  This work had never been performed before on this scale on non-military explosives within mining applications, Kelly notes.

The development of these tests resulted in a product which not only adds value for the customer but also – and most importantly – keeps workers safe, says AECI surface South Africa regional manager Edward Felix. Further small-scale tests were also developed and refined to complement the large-scale testing, says Kelly.

Powergel X² is designed to mitigate critical hazards while ensuring operational continuity in high-risk environments.  This is particularly vital for Africa’s mining sector, as it contends with some of the world’s most challenging geological conditions, including moisture-heavy and high-temperature settings that heighten the risk of premature detonation and other safety incidents.

Felix adds that Powergel X² has been developed with a higher safety factor to reduce these risks and improve inhibitive properties within reactive ground.

There is a strong uptake of Powergel X² among mining companies in Africa that want improved safety protocols in hazardous environments. Many operators encounter difficult hot-hole and/or reactive ground conditions, says AECI global portfolio manager Hendrik Botha.

AECI has observed enhanced performance where Powergel X² has been rolled out, especially in areas previously considered too high-risk for conventional blasting, he notes. The product’s straightforward application helps to streamline handling processes on site – a critical factor in maintaining consistent blasting schedules.

Powergel X² also has the potential to help reduce logistical complexity in remote areas. With the versatility to address reactive- and hot-ground conditions, the product reduces the need for multiple explosive types in a customer’s product basket, consequently simplifying inventory and potentially lowering blasting solution storage costs.

By offering a single solution that covers various applications, Powergel X² assists mines in managing costs and improving inventory efficiency, Felix tells Mining Weekly. This capability is particularly relevant, as African mining operations face pressure to optimise resources and reduce operational expenditures amid fluctuating commodity prices.

Southern Africa was chosen as the initial rollout region for Powergel X². This decision was influenced by a request from a key customer with operations in challenging ground conditions. The product’s resilience in high-temperature environments aligns with the operational demands of this area, where reactive ground and hot-holes are prevalent.

AECI is also positioning Powergel X² as a solution that can be adopted in other regions with similar geological challenges.

Sustainable Mining Practices

As part of AECI’s drive to align with the Sustainable Development Goals of the UN, an eco-friendly product was developed.  Powergel Eco incorporates recycled oil, aligning with Africa’s push for responsible mining and, consequently, offering a lower environmental impact compared to that of traditional explosives. This formulation is suitable for use in holes where reactive ground is not present and hole temperatures do not exceed 60 ^oC. 

“By repurposing recycled oil, AECI Mining is addressing waste management challenges and supporting the circular economy in the mining sector,” adds Botha.

The eco-variant supports a broader trend towards reducing the carbon footprint of African mining operations by lowering emissions associated with traditional explosives. AECI’s approach reflects a larger shift among customers in Africa to balance productivity with sustainability, he adds.

The company maintains collaborations with mining companies and government agencies to develop technologies that meet safety and regulatory standards. Partnerships are essential to adapt products to the specific conditions and requirements of Africa’s mining environments, notes Botha.

He adds that AECI’s approach aims to support industry standards and regulatory frameworks that prioritise safe and sustainable practices. 

“As mining companies adopt new technologies to meet complex geological and environmental challenges, our initiatives signal a shift towards safer, more efficient

and environment-conscious mining practices across the continent,” concludes Felix.