Johnson Matthey’s Stationary Emissions Control (SEC) group reports that sales of its Selective Catalytic Reduction (SCR) systems, which use their own proprietary urea (or aqueous ammonia) injection control systems, have exceeded 3.4 gigawatts (GW) of stationary engine power for applications worldwide.
Johnson Matthey has sold its SCR systems for engines ranging in size from a few hundred KW to 20+ MW. In addition, these engines have been fueled by ultra-low sulfur diesel (ULSD), natural gas, propane, digester gas, landfill gas, dual fuel, blended fuel, Biodiesel or heavy fuel oil (HFO). The SCR systems incorporate extruded, plate-type or metal monolith SCR catalysts – all manufactured by Johnson Matthey. The catalysts are designed to maximize catalyst activity and durability, while simultaneously minimizing back pressure, ammonia slip and catalyst maintenance.
Jeff Sherman, Johnson Matthey SEC LLC President, said the Johnson Matthey SCR system includes robust and durable SCR catalyst, a rugged housing design, a fully optimized mixing duct, a high uptime urea injector, and a state of the art urea dosing system / control panel. The latest generation of Johnson Matthey’s SCR system is even more compact and offers significant cost savings to our customers. In fact, when combined with Johnson Matthey’s own diesel particulate filter technology, the SCR system can be integrated into a single housing, Tier 4 engine upgrade package.
In the SCR process, exhaust gas flows through the catalyst, an integral part of the exhaust gas line, with a precisely dosed injection of urea (or ammonia). Urea serves as the ideal reducing agent since it can be shipped and stored easily and is colorless, odorless, nontoxic and bio-friendly. Both aqueous solutions of ammonia and urea have proven their suitability for the catalytic reduction of NOx in many other applications.