The Frequently Asked Questions section is designed to provide quick, clear answers to most frequently asked questions. As MineTerra’s products, services, and technologies continue to grow, this page serves as a central place to address common inquiries, clarify processes, and provide helpful guidance for operators, partners, and customers. Whether users are looking for technical details, support information, or general explanations, this FAQ hub makes it easy to find reliable, up‑to‑date insights without searching through multiple pages.
When there is insufficient temperature for proper passive DPF regeneration, an active DPF system can often be employed. An active DPF will artificially increase the exhaust gas temperature to a level that will oxidize soot that has accumulated in the system. There are several means of increasing the temperature, including an electrically charged heating element upstream of the DPF, boosting exhaust gas temperature, prompting soot regeneration. Some of these systems require that the operator manually start the process on a switch panel, and others start automatically as they sense that back pressure is approaching a pre-set upper limit.
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.
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.
A simple back pressure warning device or magnehelic gauge is sufficient to ensure that pre-established back pressure limits are not exceeded during daily operation.
A data log device provides duty cycle information that is needed to pre-determine if there is sufficiently high exhaust temperature and time at this high temperature, to support the proper functioning of a passive DPF system
It's not necessary to leave a data log device fixed to a machine, unless you would like to continue gathering data once the emission control device is fitted. It's typically beneficial to review temperature and backpressure data once the emission control device is fitted since you will be able to identify trends such as actual exhaust gas temperature as it relates to regeneration of the device.
Fleet managers typically leave a data log device on at least one machine (of each machine model) to evaluate the emission control system performance prior to fitting the same device on other machines of the same model in the fleet.
Portable emission test equipment is usually used to check gaseous emissions downstream from the device. Such testing is typically performed when the machine is stationary, under a "hydraulic stall" (full throttle / full load) test procedure. This emission data is usually compared to the exhaust temperature and gaseous emissions up-stream of the emission control device to determine actual percentage reduction of emission at that point in time. Back pressure at the time of emission testing (still under full load) helps to validate the selection emission control device.
MineTerra can provide retrofit diesel emission control systems for machines fitted with engines that are certified to EPA Tier 1, 2, or 3 emission levels. Engines that were manufactured prior to these emission standards produce emissions that are considerably higher in particulate matter, thus will result in rapid plugging and escalating back pressure that can damage the engines. Machines that have low duty cycle / low exhaust gas temperature can typically be fitted with a MineTerra actively regenerating filter system that will automatically increase the exhaust gas temperature and regenerate as needed. These systems, like passively regenerating systems, will reduce particulate matter (black soot) by 95 – 98%, as well as carbon monoxide and unburned hydrocarbons by high 95%+.
Please contact us for a free evaluation of your engine and fuel combination regardless of EPA Tier level and diesel fuel – biodiesel blend.
