Blasting and mining companies should collaborate to find ways of performing blasts efficiently, says commercial explosives supplier AEL Indonesia technical manager Carlos Paz, noting that blasting projects should also be approached more innovatively to drive cost reductions.

He adds that electronic detonators play an important role in achieving cost effective, optimal blasts, right down to the correct millisecond.

“Within the drill and blast industry, explosives companies continue to develop technologies that can further increase production while reducing costs, which is a welcome approach.”

Paz says electronic detonators are helping to optimise processes along the mining chain as products such as electronic initiation systems designer DetNet’s DigiShot Plus electronic blasting system enable flexible blast designs, with electronic delays of between one millisecond and 20 seconds.

However, Paz says there is no one-size-fits-all timing when blasting, as many related factors, including the type of rock, need to be taken into consideration.

“While electronics have been on the market for some time, a small proportion of operations know how to identify the optimal delay timing.”

He says that one of the most effective ways of determining this optimal delay is by carrying out ground response and face velocity analyses to obtain data on how the rock mass responds to different parameters of drill and blast design.

Optimum timing leads to greater vibration control and fragmentation of the rock, which provides operational cost reductions, such as a reduction in fuel for vehicles needed to move the fragmented rock as well as improved efficiency of crushers and mills owing to reduced rock sizes, says Paz.

He highlights a ground response case study done by AEL Indonesia at integrated coal producer PT Bayan Resources’ Gunung Bayan Pratama coal mining operation, in Indonesia, which examined how the ground reacted to the detonation of explosives, in terms of time, through the use of high-speed cameras, laser profiling and use of AEL Indonesia’s blast design software.

“By collecting and analysing the data, AEL Indonesia recommended higher burden relief to allow enough time for the rock mass to heave and generate free face for the following rows and avoid back break. Quick intra-row delay was also suggested to avoid the loss of gasses between the stratums which were also observed in the filming,” Paz explains.

In addition, AEL Indonesia also managed to identify the optimal delay time and applied the DigiShot Plus electronic system to achieve an increase in the mine’s productivity to 10% over the target, which Paz says highlights the benefits of electronic systems.

“Given these results, in the next few years the increased use of electronics and the predictability of performance and outcomes will see greater market share growth in South Africa, Indonesia and the rest of AEL Mining Services’ markets.”

AEL Indonesia, based in Indonesia’s capital Jakarta, is a subsidiary of South Africa-based commercial explosives developer and supplier AEL Mining Services.