(Case Study of the Use of MTi Blastbag TM in a Limestone Quarry in Buenos Aires, Argentina)
Challenge
Argentina has limestone quarries, which are the primary source of raw materials for cement production. The blasting process is carried out by expert blasting service providers. The primary goal of this blasting is to achieve the desired rock fragmentation.
Blasting was carried out 100 meters away from the processing plant, with a powder factor below 150 g/t. Powder factor is defined as the ratio of the amount of explosive used to the volume of rock produced by the blasting process. Previous blasts in the same area had caused significant vibration.
The bench height is 22 meters. Drilling typically consists of 20–30 holes with a 6-meter burden and an 8-meter spacing pattern . The drill hole diameter is 6 inches, the hole depth is 23 meters, and the subdrill is 1 meter.
The blast hole is typically filled with a single column of explosives 18 meters high. However, the spacing in the blast pattern was reduced to 7 meters to address rock agglomeration. The use of two airdecks with MTi BLASTBAG ™ Aero helps reduce vibration and improve rock fragmentation.
The use of an airdeck reduced explosive consumption by 1708 kg for 21 holes.
Blasting with an air deck produced a transverse peak particle velocity (PPV) of 53.2 mm/s, slightly exceeding the 50 mm/s limit. However, vibration was significantly reduced and vibration frequency increased.
Results
The blasting service provider successfully achieved the desired blasting and fragmentation results. At the same time, they were able to reduce operational costs by reducing explosive consumption by 18%, from 951.8 kg to 781.0 kg, through the implementation of an air deck.
Although this air deck method involves the use of MTi BLASTBAG TM Aero in the blast hole, this cost reduction is largely offset by the resulting reduction in explosive consumption.
This study concluded that the use of a designed air deck significantly improved the desired blasting results. Please contact us for further information; we will be happy to answer your mining blasting needs .
