24 May 2006
Japan’s Mitsui announced the introduction of urea quality sensor technology in the US market. The sensor has been designed to monitor the quality of urea solutions used in selective catalytic reduction (SCR) systems for NOx emission control from diesel engines. The sensor technology will be marketed in the USA by Mitsui Mining & Smelting Co. of Hoosick Falls, NY.
The sensor is a second-generation technology, currently being tested. The first generation sensor was introduced last year on heavy-duty trucks fitted with urea-SCR systems in Japan. While ensuring that a specific quality of urea is delivered into the exhaust gas stream, the sensor also has the ability to act as a multifunction sensor, said Mitsui.
Urea-SCR technology will likely be used in North America to comply with the US EPA 2010 emission standards for heavy-duty truck and bus engines. However, compliance issues exist with the SCR technology. If the engine was operated without urea solution in the onboard urea tank, excessive NOx emissions would occur. Using a urea quality sensor, the SCR system can be designed to prevent the possibility that the urea tank is filled with other fluids, e.g., with tap water, instead of the urea solution.