Date: Jan 01, 2010 Source: EPA SBIR Success Story (
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Environmental Problem:
Nitrogen oxides (NOx), which are among the primary pollutants emitted from vehicle exhaust, cause significant environmental and human health issues. Adverse respiratory effects associated with NOx include airway inflammation in healthy people and increased respiratory symptoms in individuals with asthma. NOx exposure concentrations in vehicles and near roadways are appreciably higher than in other locations and are of particular concern for susceptible individuals, including children and the elderly. Monitoring the NOx concentration in exhaust streams is critical for the reduction of NOx emissions and compliance with EPA s clean air regulations.
SBIR Technology Solution:
With support from EPAs Small Business Innovation Research Program (SBIR), Ceramatec, Inc. has developed multiple types of sensors that can monitor the NOx concentration generated by combustion in diesel engines. These devices offer fast response and high sensitivity to NOx, low cross-sensitivity to other species, such as carbon monoxide (CO) and sulfur dioxide (SO2), and can perform for extended periods in engine exhaust from mobile sources. These sensors will improve emissions monitoring and enforcement of emissions regulations for both on-road and off-road mobile sources.
Many promising emissions-reduction devices have been developed in recent years, such as NOx absorbers, selective catalytic converters (SCR), exhaust gas recirculation (EGR), and oxygen-enriched air injection (OEAI) technology. Information obtained by online NOx monitoring can be fed back into the process control system so that process variables can be optimized to re duce pollution.
Ceramatec's ceramic-based sensor successfully withstood high temperatures present in an engine exhaust stream (500-600° C). When measuring NOx concentrations, the sensor was not affected by the gas input nitric oxide (NO)/nitrogen dioxide (NO2) ratio; the sensor voltage was found to be proportional to the total NOx concentration. The sensor had no response to cross-sensitivity with carbon dioxide (CO2) and water vapor, although cross-sensitivity to up to
1,500 ppm of CO and 15 ppm of SO2 affected the baseline voltage of the sensor. The NOx sensor demonstrated sensitivity to NOx levels as low as 1 ppm. As a final step in Phase II, Ceramatec miniaturized the sensor into a smaller device that could be threaded into an exhaust port.
Commercialization Information:
In November 2009, a new company, EmiSense Technologies, LLC, was formed to commercialize this efficient, durable, and cost-effective NOx sensor. Ceramatec is providing advanced diagnostic and analytical services to EmiSense.
EmiSense is commercializing other advanced sensors, including electronic-field particulate matter (PM) sensors and oxygen or Lambda (air/fuel ratio) sensors, to promote clean emissions and help address the global challenges of fossil-fuel dependence and climate change. CoorsTek provides high-volume ceramic foundry services to the company.
EmiSense's intake high-speed oxygen sensors are used to manage exhaust gas recirculation for diesel, gasoline direct injection, homogeneous charge compression ignition, and other high-efficiency engines.
The company's engine out oxygen, NOx, and PM sensors are used for closed-loop engine controls. Its after treatment oxygen, NOx, and PM sensors are used for on-board diagnostics emissions compliance and closed-loop controls of catalysis and particulate filtering. The advantages offered by EmiSense's sensors include:
• Superior response time
• Automatic calibration for sensor drift compensation
• Simplified, low-cost controller implementation
• Simplified single-cell wideband sensors
• Detailed sensor diagnostics
• Individual-cylinder balancing
• Misfire detection
• Faster "light off" time
• Improves resistance to thermal shock
• Improved resistance to mechanical shock
Company History:
Ceramatec was founded in 1976 as a technology spin-off from the University of Utah. The company specializes in the use of ceramics to develop cutting-edge technology. In its first 25 years, Ceramatec focused on sodium-sulfur batteries and their applications in industrial environments. Since 1990, the company also has focused on fuel cells, oxygen separation, new energy, and environmental technologies.
In 2006, Ceramatec was a Utah Innovation Award Finalist for best NOx sensor. Because of the company's success, the number of Ceramatec employees has tripled during the past 7 years. CoorsTek, North America's largest supplier of technical ceramics, serving diverse industries, includes automotive, industrial and semiconductor segments, acquired Ceramatec in 2008,.
EmiSense was formed in 2009 via a merger of assets, intellectual property, product lines, trade secrets, and capital from CoorsTek, Inc. and Innovate!
Technology, Inc. Prior to this merger, the EmiSense research team developed advanced emissions sensor technology as a part of Ceramatec, a CoorsTek R&D subsidiary. The new company integrates CoorsTek intellectual property and high-volume global manufacturing capacity with Innovate's award-winning DirectDigital sensor technology and signal-processing patents.
EmiSense develops smart sensors for clean emissions. Its products are critical enablers for next generation, high-efficiency engines and generators, which help address the global challenges of fossil fuel dependence and climate change.
