Keeping dust down is never-ending battle for mine operators, but an Australian company is offering hope through a new weapon that is proving successful in trials.
At the Jack Hills iron ore mine in Western Australia, mine operator Crosslands has been experimenting with a dust suppressant called Soiltac®. Distributed by Yanmar Soil Australia Ltd., Soiltac® is a biodegradable liquid used to control dust and erosion. The product is diluted with water and then sprayed onto roads or stockpiles. Soiltac® works by bonding soil or aggregate particles together, so that once the water evaporates, the liquid appears transparent and gives the appearance of an untouched surface.
The usual means of dust control is to use water trucks to spray water on dusty haul roads and stockpiles, but this method employs vast amounts of water than can never be recovered.
For iron ore operations, moisture content is a critical element for transporting and shipping the ore. As the product is crushed and stockpiled, it must be wetted regularly in order to minimize dust. But too much water is not only wasteful; it can also limit the amount of ore that is loaded onto a ship, thus reducing revenues for producers, whose customers do not expect to purchase ore with excessive water content.
It is therefore critical to have a system in place that maintains proper moisture ratios.
The amount of water wasted on haul roads alone makes a compelling argument for finding an alternative dust control method. A water truck holding 15,000 litres of water, that wets a road 10 times a day, would use 150,000 litres a day, or over 54 million litres a year.
While the mining industry has applied Soiltac before, using water cannons and dribble bars, and was originally developed for the U.S. Military, the Crosslands demo marks the first time the product has been used throughout an iron ore operation.
Crosslands has been using Soiltac® since 2008 without incident, the company says, applying the product on stockpiles, crusher cone stacks, and haul roads at the Jack Hills mine located 380 kilometres northeast of Geraldton.
The mine started production in 2006, and ships over 1.5 million tonnes of iron ore per year, according to the company’s website.
Crosslands CEO Stuart Hall says that the mine’s employees, contractors and surrounding communities have all noticed a difference in dust levels from Soiltac®.
“Our road transport contractor and site personnel noticed immediate
The Jack a7improvements that have been sustained over the 12 months of operation of this system,” says Hall. “In particular we receive frequent comment from visitors to the crushing and processing area as to how low dust levels are.”
Pete Rogers, a spokesman for Yanmar Soil Australia, says that Soiltac® can be applied using a dosing system that applies a small amount onto the ore as it leaves the crushing circuit and is then stockpiled. The treated, dry ore can either be stored for extended periods of time, or transported without the need for ongoing water use.
“Applying the Soiltac® product at the crushing and stockpile stage eliminates the use of water during the entire transport and delivery process and these environmental benefits are not just for the companies, minesite personnel and surrounding communities, but also for the client who receives the raw product,” says Rogers.
Click here for full list of links:
http://go.mining.com/sep10-a7improvements