Dust reduction achieved at Centennial Coal’s Mandalong Mine

In its longwall coal mine near Morisset, NSW, Centennial Coal sought to reduce significant dust emissions around its underground bin.

At full production, the company’s Mandalong Mine produces 5.5 million tonnes of coal each year from its underground Newcastle coalfields. At the point where the coal drops from the crusher to the underground bin, a substantial dust problem was being experienced.

“Centennial Coal had tried a number of approaches to remedy their dust problem,” said Graeme Cooper, Managing Director of Tecpro Australia. “When these didn’t prove as effective as they wanted, they contacted Dr Ting Ren from the University of Wollongong for advice.”

Dr Ren and his team conducted CFD modelling to identify the source and direction of the airflow that was carrying the dust. Having previously collaborated with Tecpro Australia in developing dust suppression solutions in other mining environments, he also suggested that Centennial Coal contact Cooper for his recommendations.

“I visited the site and reviewed the results of Dr Ren’s CFD modelling,” said Cooper. “In partnership with Ben Cruickshank, from Centennial Coal’s engineering team, and Dr Ren, we discussed the best approach to suppressing dust in the vicinity.”

Arising from these discussions, Cooper and the team at Tecpro custom designed a dust suppression solution.

“With the information we had from the CFD modelling, we developed detailed drawings indicating the best positioning of hose and droppers to combat the dust,” he said. “Following this we were able to select the best spray nozzles to best suit the particular requirements for this application. Our system works by directing a fine curtain of water droplets inwards from the rim towards the crusher in the centre and has the effect of containing and suppressing the dust being generated. Aided by gravity, the dust particles fall into the bin instead of remaining airborne.”

Following installation by Centennial Coal, Coal Services Health measured the impact of the system, but at the time of testing, only half of the nozzles were in operation. Nevertheless, dust emissions had reduced by 68%.

“We are confident that now all of the nozzles are operating, the dust suppression system will be reducing the dust by more than 90%,” said Cooper.

The improvements in air quality achieved through the installation of the dust suppression solution have helped Centennial Coal continue its ongoing program of improving environmental safety.