Increasing the safety of coal miners

The ARC Industrial Transformation Research Hub for Nanoscience-based Construction Material Manufacturing (the NanocommHub) is a multidisciplinary research hub that aims to transform the construction materials industry. Administered by Monash University, the Nanocomm Hub has over 50 partners from Australian industry, research and higher education organisations.

Chief Investigators, Associate Professor Ting Ren and Professor Alex Remennikov, both based at the University of Wollongong node of the Hub, have been working to create a new protective system for continuous miners in underground coal mines.

The project is intended to meet new industry standards that were put in place following a 2014 New South Wales coal mining tragedy in which two miners died 500 metres underground. The men had been operating a continuous mining machine when hundreds of tonnes of coal collapsed on them. This tragedy sparked an investigation that determined that existing protective systems were inadequate, prompting tighter safety regulations.

'We wanted to design a new protective system that could be installed on continuous miners as the last line of defence after all other mitigating measures fail,' explains Associate Professor Ren. 'Our aim was to protect people working on these machines against the hazard of coal bursts while building roadways in highly stressed coal seams.'

The researchers modelled the impact of ejected coal fragments and devised formulas to predict the dynamic load and kinetic energy of flying coal and the resulting impact on continuous miners. They then developed a prototype protective system which could be readily assembled underground.

 

	The researchers have collaborated with industry partner peter holt of ironclad mining machinery to develop a system of energy absorbing panels that can be readily assembled underground to protect continuous miners from dangerous coal bursts. The system was showcased at the 2021 resource operators conference and generated significant interest in its applications.

The system they developed contained a number of energy-absorbing honeycomb panels made of very thin steel, with a height of 1.5 metres to protect the full body of a miner. A cover plate is robotically attached to the honeycomb core with several hundred welds.

Through dynamic impact testing, the team assessed the energy-absorbing capacity of the panels and found that, even with 600 kg of coal dropped from a 5-metre height at a velocity of 9 m/s, the panels could absorb a significant amount of energy without disintegration.

Having demonstrated the effectiveness of the system, the researchers are now in discussion with coal industry operators and coal industry equipment designers to generate interest in its further development and applications.