The challenge
A deadly disease
The disease is known as coal workers pneumoconiosis (CWP), or black lung.
It’s caused by prolonged exposure to coal dust, is usually debilitating and can be fatal.
It was thought to have been eradicated in Australia by the introduction of better monitoring and mitigation strategies in coal mines.
But in recent years, dozens of cases of CWP in the Australian coal industry have emerged, making it urgent to develop better technologies and strategies to reduce the exposure levels of coal mine workers to respirable coal dust.
Reducing mine workers’ dust-exposure levels in underground coal mines remains a challenging priority for mine operators, particularly in high-production longwall faces. In many longwall faces, dust migration towards the walkway area is very high and results in high dust exposure for workers in these areas of a mine.
Our response
Attacking coal dust with science
We dedicate significant expertise and investment towards a comprehensive mine dust research program.
This includes:
- computational fluid dynamics (CFD) modelling studies to understand airflow patterns and respirable dust-concentration distribution along the longwall face
- development of dust-control strategies including novel concepts to minimise dust migration
- optimising sequencing of water sprays to minimise caving-generated dust migration into the walkway area
- investigation of the effect of air velocity and water sprays on respirable dust concentration along the longwall face
- development of field-based technologies for real-time monitoring of respirable dust exposure and end-of-shift measurement of silica content of respirable dust
- laboratory studies on dust sampling, dust characterisation including morphology and particle size distribution, and silica analysis of respirable dust, and
- development of photocatalytic technology for better control of diesel engine exhaust emissions in underground coal mines.
The results
From the lab to the longwall: coal dust mitigation
We have worked with numerous mining companies to develop effective mitigation technologies and strategies to reduce worker exposure to coal dust.
Results of CFD modelling studies provided a comprehensive understanding of the respirable dust distribution patterns on the longwall face and the impact of various dust-control strategies.
Dust-control strategies were developed to minimise workers’ exposure to intake dust sources which are now implemented at numerous mine sites.
These strategies included the installation curtains to deflect dust-laden air towards the face side and clean air towards the walkway area of the longwall face.
For shearer operators we developed a novel concept to minimise dust exposure.
Our studies showed that a better-designed shearer scrubber can capture a significant proportion of dust generated at the leading cutting drum.
This not only reduced the volume of dust but also reduced the dust roll-up towards the walkway on the longwall face.
Field observations and dust monitoring results during scrubber field trials showed a significant reduction in respirable dust concentration levels in the longwall walkway.
We also developed an optimum sequence for the operation of water sprays in caving shields to minimise caving-dust migration into the walkway area, which has been implemented at a trial mine site.
The projects have been supported and undertaken in collaboration with the Australian Coal Industry Research Program (ACARP) and individual mining companies.