Could next-gen surface miners change face of NZ quarrying?Sponsored
New technological innovations are having a transformational impact on quarrying around the world. One of the most groundbreaking developments has been the increased use of continuous surface mining machines to extract material without the need for drilling and blasting or ripping with excavators.
An opportunity to work smarter, not harder
In an industry as old as quarrying it’s rare to see a new technology transforming the way work is done. But continuous surface mining machines are growing in popularity among quarry operators and companies undertaking civil construction projects.
On benchtop quarries and large low-gradient civil projects, their productivity allows them to do the work of multiple excavators. They are also winning plaudits for reducing dust, noise and vibration compared to more traditional drilling and blasting techniques.
“The technology built into modern surface miners is truly impressive,” says Adrien Merceron, general manager at Marais Laying NZ, who represents the Italian manufacturer Tesmec in New Zealand.
These technologies include customised milling heads for different rock and mineral types and feature advanced automated digging and route guidance technology that allows even a novice machine operator to be highly productive with minimal training. Dust suppression hoods are available for many models and some of the top manufacturers also offer remote fault-detection and assistance for any issues.
“Surface miners are still the new kid on the block in New Zealand, but those using them are reaping the benefits and they are now widely used in many countries overseas,” Merceron says.
How surface mining transformed ops at three Palmer Resources-run Canterbury quarries
One of the earliest adopters of continuous mining machines in New Zealand is Palmer Resources. General manager Shaun Cleverley says the business was the first operator in New Zealand to use surface mining when it began trialling a cold milling machine traditionally used in roading five years ago.
The trials proved a success, resulting in a decision to purchase the 975 EVO Rock Hawg surface miner from Tesmec in 2022. It is now operating at three of the company’s Canterbury limestone quarries, replacing blasting or ripping with excavators as the method of extraction.
“The new specialised machine is more efficient on diesel than the cold milling machine, is able by quarrying right up against square rock faces to reach into square corners and even does primary processing as part of its operation,” Cleverley says.
“Blasting is fast but there’s a lot of processing to be done afterwards. With surface mining we’ve seen a 30 to 40 per cent cost reduction per bank cubic meter of limestone taken out of the ground.”
Cleverley says surface mining has meant fewer staff are required on site at any given time, leading to savings on operational costs.
Diesel consumption for the Tesmec 975 EVO is around 37 litres per hour – less than half of the 80 litres per hour used by the cold milling machine. At just 47 tonnes, it is light enough to be transported on the back of a heavy transport truck, allowing the one machine to be used across multiple quarries.
Although the machine can operate in ‘upcutting mode’, discharging excavated material onto a conveyor belt, Cleverley says his team has found ‘downcutting mode’ to be the best fit for them, with the machine leaving crushed rocks in-situ to be loaded onto trucks at a convenient time.
Surface mining is an ideal fit for limestone quarries, he says, due to the density of the rock. “In the ideal conditions at our limestone quarries, we can easily have outputs double or triple that of traditional excavator or dozer ripping.”
“There’s a band of material that surface miners are perfect for. Soft rock is all good, but excavators with rippers are alright in the environment, while harder rock with an MPa above 80 or 90 is likely to still require blasting. In the ideal conditions at our limestone quarries, we can easily produce 100 tonnes an hour.”
Merceron, says he is thrilled to see the technology gaining recognition and traction in New Zealand. “The machines have proven their worth around the world, not just in quarrying but also in civil construction. They are purpose made for quarrying but they are also used for a wide range of other purposes, from preparatory works on wind farms to groundwork for new runways at airports.”
The team has trained Tesmec technicians located in Auckland, Wellington and Christchurch to provide training on the Rock Hawg surface miner, along with maintenance, servicing of the machinery and GPS mapping of sites, Merceron says. Standard parts are kept in Auckland and Christchurch, with heavy parts available from Australia, ensuring any downtime for repairs are kept to a minimum.
Want to know more?
Interested in a continuous surface mining machine? Get in touch with Tesmec representatives in NZ today.
Our friendly team is happy to answer your questions and can perform a quarry site assessment to determine your New Zealand quarry's suitability for surface mining.
Contact us :
infomaraislayingnz@samarais.com
0800 627 247
https://www.maraislaying.co.nz/quarry-surfacemining