Grantee Research Project Results

Final Report: A New NOx, HC, and Small Particle Filter With a Regeneration-In-Place Capability for Stationary Diesel Engine Applications

EPA Contract Number: 68D00280
Title: A New NOx, HC, and Small Particle Filter With a Regeneration-In-Place Capability for Stationary Diesel Engine Applications
Investigators: Nelson, Sid
Small Business: Sorbent Technologies Corporation
EPA Contact: Richards, April
Phase: II
Project Period: September 1, 2000 through September 1, 2002
Project Amount: $225,000
RFA: Small Business Innovation Research (SBIR) - Phase II (2000) Recipients Lists
Research Category: Air Quality and Air Toxics , SBIR - Air Pollution , Small Business Innovation Research (SBIR)

Description:

Diesel engines are used extensively today as power sources in small- and medium-sized applications. They will continue to be used extensively in the future because of their low cost and high efficiency. The environmental benefits of using modern diesel engines for power generation include low carbon dioxide and hydrocarbon emissions. Unfortunately, diesel engines produce large amounts of nitrogen oxides (NOx) and particulate matter.

A new technology, the NOx and Small-Particle Filter, was developed by Sorbent Technologies Corporation specifically for controlling NOx, volatile organic compounds, and particulate emissions. It is the result of 7 years of research and development and successful demonstrations. Originally, the technology was developed for controlling pollution from jet engine test cells. The goal of this project was to improve and adapt the new technology to operate on stationary diesel engine exhaust gases.

This project successfully demonstrated the feasibility of adapting the NOx and Small-Particle Filter as an easily retrofittable, cost-effective NOx control technology for heavy-duty diesel engines. The technology utilizes a special carbon-based sulfur-tolerant, high-capacity, NOx -selective sorbent material to adsorb the pollutants out of the exhaust gas stream and then directs a concentrated NOx stream to a NOx decomposition system that converts the pollutant into nitrogen and oxygen.

Because the filter adsorbs NO at low-temperatures, the unit can be retrofitted at the very end of the diesel exhaust train. A catalytic particulate trap installed somewhere upstream of the NOx filter protects the filter while significantly reducing the diesel particulate emissions. This simple, innovative scheme uses no consumables and little energy from outside. It can be applied generically to any new or retrofitted NOx emission source.

The work described in this report was performed by Sorbent Technologies Corporation, the technology developer, as well as The Pennsylvania State University's Energy Institute, as a subcontractor-primarily for testing the new technology on engines at the Institute’s Diesel Combustion and Emission Laboratory.

Summary/Accomplishments (Outputs/Outcomes):

• The carbon-based NOx filtration material can be made into monolithic cartridges for space-efficient utilization with high NOx removal efficiency, reasonable pressure drops, and reasonable structural strength.

• These NOx filter cartridges effectively adsorb NOx from actual diesel exhaust gases when the gas temperature is dropped to about 130°F and desorb the NOx when the material temperature is above 230°F. This phenomenon occurs regardless of whether the NOx is in the form of NO or NO2.

• Components of the NOx filtration system can be miniaturized to the extent that they can be packaged on a small skid for easy installation.

• Electric resistance (Joule) heating of the sorbent beds is the most effective method for directly heating the solid sorbent material when it is formed into a monolithic cartridge.

• Consistently greater than 80 percent NOx conversion can be achieved in the decomposition system.

Conclusions:

The technology was successfully demonstrated as an integrated system at a commercial scale for stationary diesel engines. Up to 80 percent NOx removal and decomposition and 95 percent particulate removal were achieved. The next step in commercializing the technology is to build several prototype systems and operate them in different commercial applications.

Supplemental Keywords:

NOx, hydrocarbon, small particulate filter, regeneration-in-place capability, stationary diesel engine applications, sorbent, smog, ozone, PM, particulate emissions, air pollution, stationary sources, small business, SBIR., RFA, Scientific Discipline, Air, Toxics, Waste, Ecosystem Protection/Environmental Exposure & Risk, Sustainable Industry/Business, particulate matter, Chemical Engineering, air toxics, Environmental Chemistry, Ecosystem/Assessment/Indicators, Ecosystem Protection, Sustainable Environment, Chemistry, HAPS, VOCs, Technology for Sustainable Environment, Ecological Effects - Environmental Exposure & Risk, Incineration/Combustion, Engineering, Engineering, Chemistry, & Physics, Environmental Engineering, Ecological Indicators, Nox, particulates, Nitrogen Oxides, combustion systems, hydrocarbon, diesel engines, Sulfur dioxide, small particle filter, SO2, combustion technology, hydrocarbons, regenerable filter system, nitrogen oxides (Nox), Volatile Organic Compounds (VOCs)

SBIR Phase I:

A New NOx, HC, and Small Particle Filter With a Regeneration-In-Place Capability for Stationary Diesel-Engine Applications  | Final Report