17 June 1999
DCL International, a Concord, ON, Canada, based manufacturer of engine emission controls, announced an installation of SCR (selective catalytic reduction) NOx control catalyst system on a diesel powered construction excavator. According to the company, it is the world's first installation of SCR technology on mobile off-road diesel equipment.
The SCR catalyst and control system was supplied by Siemens Westinghouse Power Corporation, Catalyst Systems Division, of Roswell, GA. Siemens has engineered SCR NOx emission control systems for large stationary electric power generation plants around the world for the last 15 years. In recent years, the SCR technology was also applied to diesel engines for marine propulsion and on-highway truck use, which necessitated some design changes and "downsizing", which was useful and transferable to this project. Siemens in Germany is also working on adapting the SCR technology, termed SINOx, to diesel cars.
The installation took place at Deer Park, TX, facility of Safety-Kleen Corporation on a large Caterpillar 225B excavator which is operated indoors. After a few start-up issues were corrected, the system has been running problem-free since November 1998. The system provides 80% NOx reduction which is guaranteed by DCL.