Cleaire Advanced Emission Controls’ Long-
Mile diesel particulate filter can reduce
particulate matter by more than 85 percent. Its
low exhaust temperature requirement makes
it compatible with lighter duty cycles.
In conjunction with transporting students to and from school safely, many pupil transporters are passionate about working to ensure that the air students breathe around buses is clean.
From diesel particulate filters (DPF) to diesel oxidation catalysts to crankcase filtration systems to a hybrid system for school buses, there are numerous products available to the industry that reduce buses’ particulate matter and emissions output.
SBF spoke with officials from four companies about their products’ features and specifications.
Cleaire Advanced Emission Controls LLC
Cleaire Advanced Emission Controls offers four DPFs that can be used as a retrofit solution for school buses: the LongMile®, the Horizon®, the Vista™ and the Longview.
Kevin Harris, business development manager, says the Horizon is the most popular model, but the company believes the LongMile will soon become the more popular option.
Both DPFs have been verified by the California Air Resources Board (CARB) to reduce particulate matter by more than 85 percent, and they have a modular design that facilitates service and de-ashing.
The Horizon is an active DPF with electric heater regeneration. It is verified for use in engine model years 1960 to 2006, but it cannot be used in two-stroke engines.
The LongMile DPF is a passive system that uses an exclusive sintered metal filter. It is verified for use in engine model years 1993 to 2006.
Harris says there are several features that differentiate the LongMile from other passive DPFs.
“For passive systems, you need to have a certain exhaust temperature profile, and typically it can be 260 degrees Celsius for 25 percent of the time. With the LongMile, it’s 260 degrees Celsius for only 7 percent of the time,” he explains. “This low exhaust temperature requirement provides broader engine coverage and greater operating flexibility for the fleet.”
In addition, the LongMile’s low backpressure makes it compatible with many engine applications, especially those with exhaust gas recirculation (EGR) technology. Finally, its high ash capacity extends filter deashing/cleaning by three times compared to channel wall-flow filters.
Harris notes that a school bus equipped with a well maintained and properly working engine will enable all of the DPFs to work more effectively and reduce maintenance.
“With a poorly tuned engine, the filter is going to fill up more quickly than with a well maintained engine. This means that you’re going to have to regenerate more often or clean out the filter more often,” he says.