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Show the differences between baseline emissions and emissions under conditions optimized for low N O x were very small. Commercial Application of the TFS 2000™ System Regulatory agencies in the U.S. are requiring NOx emissions levels as low as 0.10 lb/106 Btu for new, pulverized coal-fired utility boilers. Compliance requires combining a low N O x firing system with an SCR reactor. The optimum "duty" split between these systems is highly dependent on coal quality, boiler and catalyst performance requirements, and life-cycle costs. When appropriate, maximum in-furnace N Ox control appears to be the most cost-effective approach to achieving very low stack N Ox emissions. Emissions performance similar to that obtained in the BSF is expected for the TFS 2000™ system on new unit applications because the boiler and firing system will be integrated and optimized. The rigorous development program that evaluated the impact of multiple design variables critical to tangentially-fired boilers provides a basis for prudent application of the system. Retrofit applications of TFS 2000™ technology must be approached with more reserve. Whereas new boilers are designed for very low emissions, existing units have fixed furnace dimensions that do not readily allow for the more conservative furnace heat liberation rates necessary for such low emissions. ABB C-E recognizes that final resolution of certain performance issues, such as boiler thermal performance, slagging and by-product emissions, requires actual field experience. As the next step in the ongoing TFS 2000™ system development program, ABB C-E plans to conduct field demonstrations. Recently, ABB Combustion Engineering Systems was awarded a contract for a new 250-MW pulverized coal-fired unit in the U.S. that will incorporate the TFS 2000™ system. Plant commissioning is scheduled for 1996. Summary The TFS 2000™ system integrates ABB C-E developments in coal pulverization technology with advanced fuel admission assemblies and in-furnace staging techniques. At the 15 M W t laboratory scale, the TFS 2000™ system has met its performance goals, using combustion techniques only, controlling N O x emissions below 0.15 lb/106 Btu (112 ppm), while holding carbon-in-flyash levels to less than 5%, and C O emissions to less than 50 ppm. These performance goals were achieved with three different Eastern U.S. bituminous coals. The results indicate that pulverized coal-fired boiler emissions can be competitive with those of other coal-based power generation options such as CFB and IGCC. 14 11-10 |