17 October 2003
Stamford, CT-based Clean Diesel Technologies, Inc. (CDT) announced that its Platinum Plus Purifier System—a combination of a fuel additive and a diesel oxidation catalyst (DOC)—has been verified by the US Environmental Protection Agency (EPA) for retrofitting of model year 1988-1993 heavy-duty diesel engines. Emission reductions when using the Platinum Plus Purifier were verified under the Environmental Technology Verification (ETV) test protocol.
The system was verified for use with two types of fuel with different sulfur content: (1) maximum sulfur level of 500 ppm, with verified PM reduction of 41%, and (2) maximum sulfur level of 15 ppm (ultra low sulfur), which yielded a PM reduction of 50%. The system also provided reductions in CO and HC emissions, while not causing increased NO2 concentrations.
Engine dynamometer testing of the Platinum Plus Purifier System after 1,000 hours of commercial service was performed at Southwest Research Institute (SwRI) using a 1991 Cummins medium heavy-duty diesel engine typical of those used in school buses, municipal buses, delivery trucks and refuse haulers. The verification is valid for highway, medium-heavy duty, 4-cycle, model year 1988-1993, turbocharged or naturally aspirated diesel engines.
The verification follows field trials with beverage delivery trucks used in commercial service in Texas, as well as with refuse trucks in California. CDT intends to market the system for such users as local delivery fleets and school buses with older, higher polluting engines. According to CDT, the retrofit capital cost is about 20% relative to the cost of a diesel particulate filter with high platinum loading. The system would be supplied directly to end-users, while the Platinum Plus additive could be delivered pre-blended in fuel by licensed fuel suppliers, or added to fuel on-site by end-users. On-board dosing systems are still under development.
Once verified, the system is eligible for use under the EPA’s Voluntary Diesel Retrofit Program. It may be also eligible for various state and local funding programs available for reducing emissions from in-use diesel vehicles.