Explosives manufacturer AEL Mining Services aims to export its latest offering, the safer and more environment-friendly third-generation (3G) Shock-Tube Uni-Delay LP (long-period) detonator, into Africa, specifically focusing on Zimbabwe, Botswana and Zambia.

AEL shock tube product manager Derek Nell says conversion to safer detonators is imminent, owing to the increasingly stringent safety regu- lations in the mining industry.

He points out that this move toward safer practices motivated the redesign of the company’s older-generation Uni-Delay LP shock-tube product, called the Reefmaster, to create the 3G detonator assembly.

The unit is the first of its kind in Africa and was designed specifically for narrow reef applications.

Nell says the product has undergone rigor- ous testing and trials to ensure compliance with the required standards stipulated by regulatory bodies such as the South African Police Services Chief Inspector of Explosives and the Department of Mineral Resources.

He notes that the development of the 3G assembly was also influenced by feedback from the company’s clients and its drive to expand its existing product portfolio to provide the market with innovations to streamline operations.

“We realised that there was a need for a product that could contribute to a safer working environment while remaining reliable and robust for use in the harsh underground mining operations, where it would be exposed to friction, impact, static, heat, humidity and other corrosive elements,” he explains.

The 3G detonator is designed and manu- factured at AEL’s fully automated initiating systems plant in Modderfontein where in-process checks and systems contribute to increased reliability and consistency.

One aspect of the detonator that contributes to its user-friendliness is its bright orange connecting clip that is easily identifiable in underground situations where visibility is generally poor.

The bright orange connector block enables operators to connect the blast holes quickly and easily, followed by a coupling verification, at a glance, and rapid evacuation of the blasting area.

“The blasting area is extremely dangerous; therefore, the aim is to keep the time that explosives operators are exposed to these hazardous circumstances to a minimum,” Nell emphasises.

Further, safety improvements include improved impact resistance, a reduction of primary explosives in the 200 milliseconds out-of-hole delay detonator and a significant reduction in lead compounds.

The detonator has less than 0.5 g of lead compounds, compared with the 19 g of its predecessor. This holds significant health benefits for explosives operators, who are constantly exposed to lead particulates in the working environment.

Nell states that the reduced lead in the revised assembly also offers benefits in terms of processing ore, particularly in platinum and chrome mining operations, where the process depends on material densities for separation and flotation purposes.

“The lead in the detonator is deposited in the ore after the blast. Raw materials that contain lead complicate the separation process, as lead and some of the platinum-group metals are relatively similar in density,” he points out.

Environment

“Safety is becoming more of a focus area in the mining environment and it goes hand-in-hand with environmental issues.

“Previously, AEL sent in excess of 60 t/m of lead underground in the form of detonators. This has a devastating effect on the environment. The elimination of lead solids will relieve this negative impact significantly,” Nell highlights.

Another environmental benefit of the 3G assembly is that it comprises less than half the plastic used in the production of the previous- generation assemblies, which use a large portion of plastic in the connector block.

Further, a design aspect, called friction-fit, retains the detonator in the connector clip, reducing the amount of required plastic by more than 50%.

This also reduces plastic contaminants in the underground mining area and the blasted reef, as fewer plastic components are blown apart during blasts, thereby reducing the amount of plastic that enters the underground operation’s sludge, wastewater system and the processing plants.

The plastic shards that collect in the under- ground water sumps can have a damaging impact on the pumping equipment, as well as the environment during surface disposal.

Nell says that, although AEL’s Reefmaster shock-tube product is still widely used, AEL is committed to motivating total conversion to its improved 3G detonator assembly.

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