Quarry Southern Africa September 2018 | Page 24

TECHNOLOGY Increasingly, the danger is being taken out of modern blasting. that the technology is proven, and the advances are real and can be readily developed for various applications. “Quarries are already significant beneficiaries of these better blasting technologies, as they generally must crush all the material they blast,” says Rorke. “Fragmentation is therefore even more critical in a quarry, as over-sized material holds up the crushing process and diverts resources unnecessarily into secondary breaking.” Drilling trends “For a very long time, people in the quarry and mining industry drilled and blasted in the traditional manner — and doing so, it came with various safety issues: fly- rock, over-blast pressure, vibrations, and dust. Drill holes would be tamped down with sand to prevent it blasting into the air, says George Williams, Upat mining and export manager. “Earlier this year, we were approached by a non-explosive rock- breaking cartridge manufacturing company called Nxco Mining Technologies. They have a product size in their range called ‘Rock poppers’, which has no explosives 22 _ QUARRY SA | SEPTEMBER/OCTOBER 2018 impact above ground (that is, no shockwave, no vibrations, one hundred per cent controllable fly-rock, and no dust), but once placed in a drill hole they break up rock quite cost-effectively. They are quick and easy to use and there is also no damage to essential services, which is normally the case when using explosives in confined spaces. So it is ideal for oversize removal underground.” Traditional blasting would break rock into chunks often too big to go on the conveyor into the crusher, resulting in massive waste. Rock poppers offer a choice of various drill patterns that ensures oversize rocks are broken into smaller pieces, making for a more efficient process. “This has revolutionised rock breaking and we are forming a partnership with Nxco that will utilise these rock poppers in conjunction with the appropriate Milwaukee M18CHM drilling and breaking hammer — the two technologies effectively form a single system, drastically reducing wastage while improving safety.” You can now cheaply break up a rock without all the problems that go with the use of conventional explosives. Blasting a rock face in quarrying represents the same problems as mining: Covering the drill hole and using sand to tamp it to control the blast. “We can now drill-and-blast in a few minutes, whereas in the past they had to bring in a tipper with sand and stone, which took considerable time. With our system, you need one machine, one drill bit, and explosives with some stemming material, as opposed to the pneumatic components used traditionally,” says Williams. The system has been piloted with a major mining house, with in-house training provided by Nxco for the Nonex Rock Popper Cartridges and has been approved by the group’s Tool and Health & Safety committees and the partnership is now ready to roll out. “This partnership is how drilling, in particular, can differentiate itself from the traditional bit-and-tool approach,” adds Williams. Upat’s new partnership apart, Williams points to two other major technological directions for drilling as being: cordless tools and improvements in battery technology. Drilling is moving rapidly towards cordless drills. Williams says this