Texas has proposed retrofitting as many as 60,000 diesel engines with NOx control technology as part of its plan to meet federal ozone standards. The city of Houston alone has 2,700 pieces of diesel-powered equipment with its contractors operating an estimated 5,500 additional engines.
In more than a dozen engine tests and two field trials with heavy-duty diesel engine manufacturers, Clean Diesel Technologies' ARIS system has already demonstrated NOx reductions of 70% 85% in mobile transient and steady state tests.
The plans for Texas are similar to those for California, where reductions in both NOx and particulate are being targeted.
Diesel particulate filters and urea-based SCR technologies can be used together to reduce NOx and particulates by more than 85%, says the company.