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Show THERMAL DENOX TECHNOLOGY The reduction of NOx with the THERMAL DENOx Process is predicted with a Kinetic Model of the process chemistry that has been developed and verified with measured data. The location of the Injectors in the combustion equipment is selected to optimize the reaction time and temperature for the ammonia injection for a specific piece of equipment with specific fluegas composition and NOx reduction requirements. Wall mounted injector technology was developed from empirical and theoretical research to provide optimal mixing without the maintenance associated with the older ammonia injection grid technology which is no longer used. Since the ammonia is already vaporized, no atomization is required at the nozzles. Three dimensional flow models are coupled with the kinetics to predict overall performance. EQUIPMENT CONFIGURATIONS Ammonia storage has recently become an issue at operating plants, and the THERMAL DENOx Process is equally amenable to either aqueous ammonia or anhydrous ammonia. An anhydrous ammonia vaporizer is used to maintain vapor pressure on the anhydrous storage tank, or, alternately, a once-through vaporizer is used to vaporize the aqueous solution of ammonia and water before being mixed with the carrier. The carrier is either supplied via air compressors or low pressure steam lines. Flow control valves meter carrier and ammonia flow based on feed-forward of fuel rate and/or feedback of measured NOx emission. The carrier and the vaporized ammonia is mixed prior to injection at the wall nozzles. THERMAL DENOX PROCESS APPLICATIONS EXPERIENCE: The application of the THERMAL DENOx Process has become widespread. Over 100 commercial applications of the THERMAL DENOx Process are either installed or undergoing design and construction. These applications encompass a variety of combustion equipment, including industrial and utility boilers, incinerators, and industrial furnaces. The fuels for these uni ts have included coal, petroleum coke, wood, Municipal Solid Waste (MSW), agricultural wastes, as well as gas and oil. WOOD & COAL FIRED INDUSTRIAL BOILER EXPERIENCE The THERMAL DENOX Process has been applied to a number of stoker fired boilers fueled by coal and wood. For a typical stoker boiler, injectors can be located below the bullnose before the first superheater coil. Several applications have been designed and operated on wood fired boilers of varying sizes and NOx concentrations to provide NOx reductions between 50% & 80%. The THERMAL DENOX Process has been applied to a number of circulating fluidized bed boilers firing coal or wood. Injection of ammonia typically takes place after the cyclone to avoid high solids and NH3 recirculation. Several installations of the THERMAL DEN OX Process on units of size between 280 MBTU/hour and 394 MBTU/hour have been installed and operated to produce NOx reductions between 76% and 80%. |
