While the obvious hazards in a coal mine such as the presence of gas, the threat of explosion, flooding, and the potential of the mine collapsing are always at the fore of every miner’s thoughts, there is another less obvious danger – coal dust.
There are a number of measures a mine can take to reduce high levels of breathable coal dust, which may lead to pneumoconiosis (black lung disease), and the CSIRO has been making strides forward in this area with the development of its coal dust scrubber technology.
Dr. Rao Balusu from CSIRO’s Exploration and Mining division told Australian Mining “dust control in mines is a major issue, this scrubber technology looks to reduce workers’ dust exposure.”
The latest technology “not only captures and cleans the air, but also modifies the air flow and dust patterns,” Balusu added.
While longwall coal mine dust scrubber systems have been tested before, they saw limited success due to a lack of understanding of the dust and airflow patterns around the sites for dust control.
Working with the Australian Coal Association Research Program (ACARP), the CSIRO has undertaken several projects based on Computational Fluid Dynamics (CFD) modelling to advance understanding if dust flow patters around longwall shearers and walkways under a variety of different conditions.
The new scrubber is a modular system consisting of an intake hood directed into the intake ventilation, with a hydraulic fan sucking the air into an impact filtration system, a discharge duct forcing the now clean air under the shearer body to the coal face.
The sprays also make an ‘air curtain’, stopping dust from entering the walkway and blowing away airborne dust, Basulu said.
The CSIRO carried out test of the scrubber at the BMA Broadmeadow mine over four cutting cycles. Results from these tests indicated that dust levels were down between 43% to 56%, falling from average concentrations of 1.35mg/m3 to 0.77mg/m 3 and 1.59mg/m3 to 0.70 mg/m3.
To date, early results have been encouraging with plans for the scrubber to be implemented at AngloCoal’s Moranbah mine as well, Balusu said.