MineTerra will closely evaluate your specific application, be it underground mining or diesel locomotive, and tailor a solution that will utilize the most advanced chemistry available today. At the heart of these solutions, we use exclusively Corning advanced ceramic cores, on which application specific cutting-edge catalyst coatings are applied. We leave the metal fabrication portion of the products to skilled close tolerance metal fabrication partners who select the best stainless-steel materials known to withstand oxidation and impact in the harsh underground mining arena. For those machines that we have yet to complete a DPF housing design, MineTerra will send a CAD designer for on-site dimensional take off, with design completion within several weeks.

Where there’s a need to carefully evaluate the duty cycle of a customer’s machine or entire fleet, we connect customers with independent emission control test specialists. From their careful tailpipe emission sampling and detailed reporting, we determine which catalyst coating will provide the best combination of low temperature regeneration and low tailpipe NO2 emissions. In the process of doing so, our products reduce carbon monoxide and un-burned hydrocarbons by 95%+, and particulate matter by 95 – 98%. By installing a simple backpressure monitoring device, the operator stays informed as to where they are regarding recommended upper limits of backpressure and can therefore schedule DPF cleaning before exceeding their backpressure limit.

Our approach to each diesel emission reduction opportunity is to first consider use of a passively regenerating DPF. These products do an outstanding job at reducing particulate matter as well as gaseous emissions, so long as they meet duty cycle related temperature criteria. When a machine does not have sufficient exhaust gas temperature to operate with a passive DPF (as pre-determined by operation with a data log device fitted to their vehicle), there are several viable options that will provide outstanding emission reduction performance as well. These systems are considered “active” DPFs, which increase the exhaust gas temperature by several different means. Such systems are costlier and more complex compared to passive systems, but will provide necessary emission reductions, allowing the machine to continue to operate. MineTerra has such systems available and will carefully consider all contributing factors as with passive DPFs and guide the customer to the best available solution.

To ensure logical selection of an emission control system, it’s necessary to carefully monitor the actual machine’s duty cycle and corresponding temperature profile. Such monitoring is typically done by fitting the subject machine with a data logging device. Such devices are easy to install and will record the exhaust gas temperature over numerous days operation. The data is then downloaded and used to generate a profile that indicates a ratio of time / temperature. This ratio is needed to determine viability of a passive DPF. Testing of gaseous emissions at the tailpipe allows us to make an educated selection from the numerous DPF coatings in our MineTerra toolbox.

All DPFs need to be accompanied by a back-pressure monitoring device. This is critical to ensure that the engine in a DPF fitted machine does not experience an episode of excess back pressure due to lack of proper regeneration. Excess idling, lightly loaded operation, change in diesel fuel chemistry (varying concentration of bio-diesel blends), and significant decrease in ambient air temperature to mention a few, can cause a DPF to overload with soot, increasing the back pressure to unacceptable levels.

Passive DPF (diesel particulate filter) technology provides the biggest bang for the buck, so long as the machine exhaust gas temperature is sufficient for proper passive regeneration.

During normal operation, a DPF will accumulate soot (partially burned fuel) until the exhaust gas temperature reaches a sufficiently high temperature at which time the soot oxidizes in the filter. When this occurs, gaseous emissions in the exhaust stream continue to be reduced by 95%+. A catalytic coating applied to the surface of a passive DPF will lower the temperature at which soot will regenerate, reducing overall soot build up in the filter.

Our passive DPFs have been proven many times to provide the best combination of low temperature regeneration while minimizing harmful tailpipe NO2 emissions. NOx (oxides of nitrogen) are generated in the engine's combustion chamber and passed into the exhaust system. When passing through the DPF, part of the total NOx is converted to NO2 (nitrogen dioxide) which helps oxidize the soot in the filter. In knowing what concentration of NO2 in the exhaust stream best oxidizes the soot, we're able to reduce the burden on temperature alone for oxidizing the soot. Most passive DPFs rely on NO2 to assist with regeneration, but other manufacturers are not able to determine the right concentration, either falling short with higher regeneration temperatures, or exceeding a typical industry target of less than 50 ppm NO2 emissions at the tailpipe. MineTerra's DPF coating providers have done exhaustive research to arrive at the best concentration, adjusting each coating to accommodate the different diesel-based fuels used in mining.

The chemistry of the catalyst coating is key. It's a matter of knowing the variables that affect conversion of the NO portion of NOx into NO2 and controlling those variables accordingly. Our advanced catalyst coating partners have proven to be the most effective at controlling these variables, thus providing the best available combination of low temperature regeneration and low NO2 tailpipe emissions across the full spectrum of diesel-based mining fuels.