At the request of iron-ore supplier to the steel industry Kumba Iron Ore, explosives company AEL fired a calcrete blast comprising 2 686 holes, in July, in the newly opened Klipbankfontein pit at the Kolomela iron-ore mine, in the Northern Cape.
“There was a tight deadline as the blast had to be completed in five days or the mine would have run out of loading material,” says the company.
This would have cost millions. However, eager to take on the challenge, AEL employee Dawid Muller and his crew worked on the blast in temperatures ranging from 32 °C to 36 °C.
A few mechanical breakdowns on the delivery vehicles hampered progress, but AEL notes that the team’s determination kept the project running.
“They managed to load an average of about 670 holes a day over four days. The fifth day was used for final connections and testing,” says AEL.
The sheer size of the blast posed some risk. However, the methodical approach adopted by Muller, which helped him to fire several large DigiShot Plus blasts in the past, reduced the additional risk.
DigiShot Plus is an easy-to-use, reliable electronic initiating system used primarily in surface blasting applications. The DigiShot Plus system includes wireless remote blasting capability.
Because of
the size of the blast cutoffs, AEL used DigiShot Plus in a shallow waste blast, a method that could not be risked when using shocktube alternatives.
AEL has been conducting trials at Kolomela since October 2012, having been involved in the blast operations at the iron-ore mine, regularly firing DigiShot Plus blasts in more than 1 000 holes.
Further, a combined blast comprising 2 276 holes was fired three weeks before the Klipbank-fontein pit project.
AEL reports that DigiShot Plus has regu-larly outperformed competitor products and has become the electronic detonator of choice employed in critical blasts.
“The product performed well, leaving Kumba Iron Ore very satisfied,” says AEL, adding that the ease with which the blast was completed is indicative of a successful service offering.