The Control of Diesel Particulates in Underground Coal Mines

The aims of the research for this thesis were fourfold, all of which focused at reducing employee exposure to diesel particulate in underground coal mines. The four aims were to: a) Develop a method to test disposable diesel exhaust filters and if possible improve their performance b) Investigate the relationship between maintenance and diesel particulate generation c) Highlight the benefits of newer design engines in emission reduction d) Review the research of the Tower Colliery Research group as their findings have been the basis for the development of control technologies for diesel particulate in NSW underground coal mines. Methods used to achieve these aims involved: a) The construction of a test rig to measure the efficiency and backpressure of new and used disposable filters b) The testing of the in service fleet at four of BHP Billiton Illawarra Coal mines using an R&P Series 5100 diesel analysis system mounted in a trailer c) Comparison of a newer design engine with three current vehicles under mining conditions d) A detailed statistical review of all available data from the Tower Colliery Research group. Key outcomes from research conducted for this thesis are: a) The filtration efficiency and backpressure of disposable diesel exhaust filters used by BHP Billiton Illawarra Coal have been improved. These improvements, together with changes to work practices, generate potential cost savings of $395,000 per annum while affording increased protection to equipment operators. b) Seven engines with unacceptable raw exhaust elemental carbon emissions were identified in a fleet of 66 tested. Some faults identified as causing these elevated emission levels were- blocked exhaust flame traps (scrubber tanks), incorrectly set tappets and worn injectors. c) Testing of a prototype 4WD fire protected vehicle powered by an "over the road" engine as against three current vehicles, highlighted reductions in atmospheric elemental carbon concentrations of 67 90%. Significant reductions in raw exhaust elemental carbon levels were also observed. d) A statistical review of data produced by the Tower Colliery Diesel Research group identified elevated exposures within mine transportation roadways. This outcome is significant as much research within the mining industry has focused on other areas in the belief that high air quantities in transportation roadways would limit exposures. This does not appear to be the case. The project has had a number of positive outcomes, all of which have assisted in the reduction of equipment operators to excessive levels of diesel particulate