The continuously regenerated trap (CRT) was optimized for underground mining applications. The resulting advanced continuously regenerated trap (ACRT) trap was subject of long-term evaluation and several emissions tests. The effects of ACRT systems, with a hydrocarbon injection based NO₂ suppression system, on the aerosols and criteria gases emitted by heavy-duty diesel powered vehicle were assessed using results of measurements conducted during in-situ tests at a mine surface shop.
These measurements were carried out for torque converter/hydraulic stall, high idle, and low idle conditions. The effects of this system on particulate and gaseous emissions were quantitatively determined using measurements performed in the exhaust, both upstream and downstream of the system. The effects on number concentration and size distribution of aerosols in the diluted exhaust were assessed using measurements from a fast mobility particle size spectrometer. The results of measurements, performed in the diluted exhaust with a nanoparticle surface area monitor, were used to establish effects of this system on the surface area of particles deposited in the alveolar region of lungs. The effects on CO, CO₂, NO, and NO₂ were assessed using measurements performed directly in the exhaust, both upstream and downstream of the ACRT system, using a Fourier transform infrared (FTIR) analyzer.
For all test conditions, the ACRT system was found to be very effective in reducing number, surface area and mass of particulate emissions from the tested engine. On average, the system reduced the NO₂ emissions for torque converter/hydraulic stall and high idle conditions. The operation at low idle should be minimized and/or avoided to prevent excessive NO₂ emissions. The findings from this study should help the mining industry to better understand the benefits and challenges of using ACRT systems to control exposures of underground miners to diesel aerosols and gases.
Last Updated: 19/05/2020 01:15:06pm