Reducing Diesel Soot With an Atmospheric Plasma Metallic Filter

EPA Contract Number: 68D02050
Title: Reducing Diesel Soot With an Atmospheric Plasma Metallic Filter
Investigators: Kelly-Wintenberg, Kimberly
Small Business: Atmospheric Glow Technologies
EPA Contact: Richards, April
Phase: II
Project Period: June 1, 2002 through June 1, 2004
Project Amount: $224,580
RFA: Small Business Innovation Research (SBIR) - Phase II (2002) Recipients Lists
Research Category: Air Quality and Air Toxics , SBIR - Air Pollution , Small Business Innovation Research (SBIR)


Most buses, heavy-duty fleet vehicles, and construction and farm machinery are equipped with diesel engines. The diesel engine is an energy-efficient machine, but its exhaust emissions present a serious health and environmental problem. Drastic reductions in exhaust soot have been mandated throughout the world, including the recent U.S. Environmental Protection Agency (EPA) mandate to reduce smog-causing nitrogen oxides from these vehicles by 95 percent, and particulate matter (PM) by 90 percent. EPA proposes a PM emissions standard for new heavy-duty engines of 0.01 grams per brake-horsepower-hour in engine model year 2007. Soot emissions would be reduced by 110,000 tons each year when implemented. Current control technologies, such as catalytic converters, alternative fuels, and advanced diesel engine combustion systems are only partially effective in controlling the soot generated from diesel engines. Most of today's filter-based technologies experience high operational backpressures, causing unfavorable fuel consumption. The key to the acceptability of barrier filters for diesel exhaust is the ability of the filter to be regenerated, or cleared of trapped particles, so that the exhaust backpressure remains low.

Atmospheric Glow Technologies resolved the inadequacy of filter regeneration by developing the Regenerative Plasma Filter (RPF) System. A metallic porous filter collects 90 percent of the soot from the diesel exhaust, which subsequently is oxidized with periodic exposures of the patented One Atmosphere Uniform Glow Discharge Plasma (OAUGDP). The molecular radicals produced by the plasma oxidize the captured soot at the ambient temperature of the exhaust stream (40-150 C), providing a safe means of filter regeneration at low energy costs without the need for catalysts or fuel additives. In Phase II, a full-scale commercial prototype will treat the entire exhaust stream from a 2.0 L diesel engine. The pressure drop across the filter and the mass distribution of penetrating particles will be measured. In addition, NOx, SOx, CO, and O3 concentrations will be measured to determine if secondary pollutants are generated. In 2010, the world market for motor vehicle exhaust emissions control technologies is expected to approach $72.3 billion. Approximately 330,600 heavy-duty diesel powered vehicles is are produced each year. Initial market entry estimates 5 percent, or 16,350, of these vehicles could be fitted with the RPF System, with a 20 percent market share 5 years out.

Supplemental Keywords:

small business, SBIR, exhaust, soot, filter, diesel engine, emissions, PM, engineering, chemistry, air pollution, pollution prevention, Air, Engineering, Chemistry

Progress and Final Reports:

  • Final

  • SBIR Phase I:

    Reducing Diesel Soot With an Atmospheric Plasma Metallic Filter