Some fleets may need to install an aftermarket diesel particulate filter (DPF) because their EPA ‘07 engines are approaching the mileage point at which they need to be replaced or cleaned. Engine and filter makers are offering a variety of options, including remanufactured DPFs and specialized DPF cleaners.
There is another compelling reason to look at aftermarket DPFs. Last December, California’s Air Resources Board (CARB) approved new regulations requiring reduced emissions of soot and, eventually, nitrogen oxides (NOx) from trucks operating in California starting in 2011. Affected vehicles include on-road heavy-duty diesel fueled vehicles with a GVWR greater than 14,000 lbs. Out-of-state trucks and buses that operate in California are also subject to the regulation, which aims to help the state’s air districts meet federal air-quality standards. To comply with the new regulation, truck operators can choose as remedies: purchasing new trucks, replacing old engines with new ones, or installing DPFs. The ruling says that nearly all vehicles must be upgraded by 2014, and engines older than 2010 models will have to be replaced between 2012 and 2022. Even though the regulation only affects operators who run trucks in California, other states often closely follow the state’s regulatory process, especially if they have “non-attainment areas” that fail to meet federally mandated standards for clean air. If your fleet plans to operate in California or in states considering similar legislation –– or if you just want to reduce emissions –– there is an array of retrofit DPF options to consider, with solutions based on application, engine age, duty cycle and installation configuration.
Reman DPFs
Recently, engine manufacturers Volvo, Mack and Detroit Diesel Corp. (DDC) announced availability of factory remanufactured DPF filters for their EPA ‘07 engines. Both Volvo Trucks North America and Mack Trucks Inc. are using a large-scale reman program that operates out of the Middletown, Pa. Remanufacturing Center (MRC). The program enables customers to simply exchange the used ceramic filter element from their DPF for a clean one when service is required, reducing service time and simplifying emissions control systems maintenance, according to the companies. The DPFs are remanufactured to more than 90% of original capacity by a process that begins by blowing air across the filters and removing contaminants via a powerful vacuum. Filter elements with a high level of oil or particulate buildup are baked in industrial ovens to further reduce accumulated material prior to the vacuum process, the remanufacturer states. If the filters are not remanufactured, the accumulation over time of ash and other material leads to decreased engine performance. “Our message to customers is that when they’re ready to change out their DPFs, we have a cost-effective solution to do that,” says Bob MacPherson, MRC’s manager of lean systems and new engine projects.
DDC has expanded its remanufacturing offerings with a new DPF cleaning process. This process was designed to recycle used DPFs and save downtime. The company’s exclusive de-ionized water technology is said to restore DPFs to approximately 95% of their original effectiveness. Since launching its DPF cleaning program, the company says it has recycled more than 7,000 filters. DDC service outlets are stocked with DPFs for a quick exchange. “When a truck enters a dealer, the old filter is removed and returned to Reman Central where it is cleaned. The truck gets another filter off the shelf that was cleaned previously at Central,” says Richard Marcis, manager of “reliabilt” product engineering for DDC. “Not only is the Detroit Diesel remanufactured DPF restored to almost-new, it saves our customers money because the remanufactured DPF is more cost effective than a new part.” It is the only system approved for warranty, Marcis adds.
DPF cleaners
Caterpillar offers a solution for fleets wanting the ability to clean DPFs in-house. The Caterpillar DPF cleaner works on an air-pulse system to force the ash out of the DPF. The cleaner is self contained and only requires a standard shop air supply of 105 PSI and standard 110 VAC electricity to operate, says Mike Powers, Caterpillar on-highway marketing manager. The DPF is removed from the vehicle and placed in the machine where a proprietary process provides the right amount of air in the proper sequence to clean the DPF. This process takes approximately 45 minutes; then the DPF is removed and reinstalled on the vehicle. Although the machine is similar to “base tools” that can clean DPFs made by other manufacturers, the one offered by Caterpillar is specifically customized with adapters and software for cleaning the company’s own DPFs.
Caterpillar recommends that C7/C9 powered trucks be cleaned every 175,000 miles or 5,000 hours and for C13/C15 engines every 250,000 miles or 5,000 hours. For most fleets this maintenance will be needed once every two or more years.
The Donaldson Co. Inc. offers a two-stage cleaning solution for heavy-duty diesel engine DPFs. Its DPF Pulse Cleaner uses high-volume, low-pressure pulses of air to dislodge unburned soot and ash from the particulate filter. The cleaner can accommodate DPFs from 11- to 15-in. in diameter and 13- to 20-in. long, with adapters available for other DPF sizes and shapes. The cleaning takes only 15 minutes. Extremely plugged DPFs may need to be thermally regenerated, for which Donaldson offers its Thermal Regenerator, which uses high-temperature heat to burn soot and hydrocarbons from the DPF. The highly automated process lasts seven hours. To remove ash residue, the DPF must still be pulse cleaned, however.
Donaldson is marketing these cleaning solutions to fleet service providers as well as directly to fleets. Should a fleet contract out for DPF cleaning or invest in these devices? Mid- to large-size fleets may want to consider purchasing them. “The equipment pays for itself after approximately 60 DPF cleanings,” says John Garrett, Donaldson’s sales manager, emissions.
Retrofit DPFs
OE engine makers and some aftermarket suppliers already offer a variety of solutions to make older heavy-duty diesels comply with the 2011 CARB limits. For example, PACCAR Parts dealers now offer the Engine Control Systems Purifilter, an aftermarket passively regenerating DPF approved by the CARB for installation and use in a wide variety of Class 8 truck models. It reduces particulate matter (PM) emissions by 85% and meets the new 20% NOx limit. It’s approved for use with many model-year 1993 through 2006 heavy-duty trucks, regardless of manufacturer, according to Jeff Sass, general marketing manager for PACCAR Parts. Each stainless-steel Purifilter model is available in five different inlet/outlet configurations in different sizes, depending on vehicle application, and can be mounted vertically or horizontally.
Sass adds that some local governments require compliance with current EPA standards as part of the bid process for companies that contract with them. These retrofit filters will allow older fleets to bid.
Volvo and Mack offer dealer-installed retrofit DPFs designed to work with non-EGR engines sold from 1996 to 2002. The retrofit DPF, made by Huss LLC, is integrated into existing exhaust systems, available in several sizes based upon engine displacement and horsepower, and comes with a five-year/150,000 mile warranty. This DPF uses active regeneration to clear accumulated PM from the unit’s filter element, which involves raising the heat of the DPF by injecting a small amount of diesel fuel, typically after 8 to 10 hours of truck operation. Retrofit DPFs using passive and passive/active regeneration technologies are under development for 2002-2006 EGR engines.
California-based Huss, part of the European-based Huss Group, with more than 20 years’ experience manufacturing and servicing DPF systems, also markets its own “MK” DPF system to meet CARB’s new “In-use on-road diesel vehicle regulation.” The Huss retrofit system is capable of collecting up to 99% of diesel PM emissions, exceeding the CARB requirement of 85%, says Chris McDonald, Huss’ marketing specialist.
Cummins Emissions Solutions is able to help guide fleets through prospective DPF retrofit options. Among the questions they ask a fleet to consider: What is the duty cycle of the engine, and what are the operating temperatures? How old is the engine and to what emissions standard was it built?
The percentage and type of emissions that you want (or will need) to reduce determines which aftertreatment product is best for your trucks.
Donaldson, too, has a range of retrofit emission products to help older trucks meet existing and planned CARB rules. Unless you are already familiar with CARB emissions levels, all of these details may seem a bit overwhelming, but manufacturers’ and CARB websites can help you learn more about the coming regulation and what is needed to make your vehicles comply. Funding that can help to pay for emissions reduction is available to some fleets.
“The California Air Resources Board intends to provide up to $1 billion in state money to defray the cost of buying and installing the diesel particulate filters,” PACCAR Parts’ Sass notes. “Truck operators who buy and install these diesel particulate filters now, ahead of deadlines, may be eligible for larger grants.” Even with challenged state budgets, funding is still a priority.
The not-for-profit organization Diesel Technology Forum reports that passage of the American Recovery and Reinvestment Act will make $300 million available to heavy-duty diesel vehicle and equipment owners to retrofit their fleets. Administered by the U.S. EPA, this funding for the Diesel Emissions Reduction Act of 2005 is available to government and municipal fleets. Private entities may apply, but they must qualify to partner with either a government or approved non-profit organization. The EPA’s application process is only open for a limited time, typically 30 to 45 days. Online resources to aid potential grant applicants are available at www.dieselforum.org.
