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Show initiative in late 1990, named Combustion 2000, with the intention of preserving and expanding coal as a principal fuel in the generation of electrical power. The project was designed for two stages of commercialization, the near-term Low-Emission Boiler System (LEBS) program, and for the future, the High Performance Power System (HIPPS) program. In order to maintain relevance, B& W's goals for the LEBS program have been continually refmed since the initial work began in 1992. Design performance goals began as no more than 0.21b NO/MBtu, 0.2 lb SO/MBtu and 0.015 lb particulatelMBtu with at least a 38% net plant efficiency (HHV) without increasing cost relative to a conventional NSPS plant. These goals have evolved over time to the present goals of no more than O.llb NO,fMBtu, O.llb SOfMBtu and 0.005 lb particulatelMBtu with a net plant efficiency of 42% (HHV) while reducing solid wastes and complying with anticipated air toxics regulations at or below the cost of a conventional NSPS plant. B&W is one of three industrial teams working on the LEBS program which is structured in four Phases to be executed over a seven year period. Phase I, which is completed, involved system analysis, R&D activities and component definition resulting in a preliminary commercial generating unit design. Phase II, currently underway, provides for pilot and subsystem scale testing to confirm and improve the conceptual designs developed in Phase I. In Phase ITI, designs will be developed for the construction of a Proof-of-Concept (POC) Demonstration Facility. In Phase IV the POC facility will be constructed and operated in order to prove the readiness of the technology for commercial application. In Phase I, B&W organized four teams to focus on design of the major subsystems: NOx Control, S0/particulate Control, Boiler, and Balance of Plant (BOP). As a result of those efforts, the importance of controls and sensors in achieving the integration necessary to meet the performance goals was recognized and a fifth subsystem team has been formed for that purpose. Several design options were identified and evaluated by the subsystem teams during Phase I to determine the most economical approach to meet the program goals. The resulting B&W design consists of a boiler which integrates advanced 10w-NOx combustion and limestone injection dry scrubbing (LIDS) technologies. Figure 3 shows B&W's LEBS Commercial Generating Unit (CGU) design. This paper will discuss the work performed by the NOx Control subsystem team in developing the advanced 10w-NOx control system for the LEBS plant. 3 |