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Show Phase I consisted of selection of candidate technologies, creation of a preliminary 400 MWe CGU design and preparation of an RD&T Plan for Phases II and III. The Phase II work consists of: Component Optimization, POCTF Preliminary Design and Subsystem Testing. The four major Phase II activities are listed above in the ABSTRACT and are described below. (The work on in-furnace NOx reduction is the only one completed.) IN-FURNACE NOx REDUCTION Introduction: The most cost-effective method of reducing nitrogen oxide emissions when burning fossil fuels, such as coal, is through in-furnace NOx reduction processes. For the LEBS project, the DOE has specified the use of near-term technologies to provide for these overall emissions reductions. Based on technical and economic feasibility, advanced tangential firing was selected as the primary means of NO x emissions control for the ABB LEBS boiler design [1,2]. Specifically, ABB CE's TFS 2000™ firing system, which is a proven technology and commercially available, represents the technology selected as the basis for in-furnace NOx reduction. This frring system design has been demonstrated to provide NOx emissions of 0.2 poundsfMM Btu in prior laboratory and full scale, retrofit, utility boiler applications [3,4]. The objective of recent development work was to reduce this value to 0.1 IbfMM Btu. Briefly, the TFS 2000™ firing system has been developed for minimum NOx emissions from pulverized coal frred boilers accomplished by way of combustion techniques only. Specific features of this system include the use of concentric frring system (CFS) air nozzles, where the main windbox secondary air jets are introduced at a larger firing circle than the fuel jets' close-coupled overfrre air (CCOFA) for improved carbon burnout; and multi-staged separated overfrre air (SOFA) to provide for complete combustion while maintaining an optimum global stoichiometry history for NOx control. In addition, the TFS 2000™ frring system includes flame attachment coal nozzle tips for rapid fuel ignition and a pulverizer configured with a DYNAMICTM Classifier to produce fme coal to minimize carbon losses under these staged combustion conditions. Potential enhancements to the TFS 2000™ frring system focused on optimizing the introduction of the air and fuel within the primary windbox zone to provide additional horizontal and vertical staging. These enhancements were based on controlling the combustion of the coal in a more local sub-stoichiometric environment. That is, in addition to the global staging currently applied, improved NOx reduction was sought by controlling and optimizing the mixing of the fuel and air locally through vertical and horizontal staging techniques. As is the case with all infurnace NOx control processes, it is necessary to operate the system in a manner which does not decrease NOx at the expense of reduced combustion efficiency. The objective of recent developmental work on the frring system was to reduce NOx emissions levels leaving the boiler to 0.1 pounds NOxfMM Btu while maintaining carbon in ash at acceptably low levels «5%) for high sulfur, mid-western and eastern bituminous coals. The approach used in the development and evaluation of the various frring system concepts included an integrated approach of kinetic and computational modeling, small scale experimental testing in a Fundamental Scale Burner Facility (FSBF), and larger scale combustion testing in a Boiler Simulation Facility (BSF). Both modeling and experimental testing were applied to better understand the mechanisms governing in-furnace NOx reduction and to identify potential enhancements to the TFS 2000™ frring system. Results from this testing were used in the development of advanced low NOx firing systems which were evaluated in pilot scale combustion testing [5]. The pilot scale testing and evaluation of various advanced low NOx firing systems is described below. Pilot Scale Combustion Testing: Pilot scale combustion testing of in-furnace NOx control systems was performed in ABB Power Plant Laboratories' BSF. The objective of this testing was to evaluate enhancements to the existing NOx control technologies for improved NOx emissions performance, while providing the necessary information for supporting the design of the NOx control subsystem for the LEBS Proof-of-Concept Test Facility (POCTF). The BSF is a pilot scale test furnace, nominally rated at 50 MM Btulhour (5 MWe) for coal firing, that reliably duplicates the combustion characteristics of a tangentially-frred utility boiler. All major aspects of a typical tangentially-frred utility boiler are duplicated in the BSF including a v-shaped hopper for bottom ash collection, the use of multiple burner elevations, and an arch with subsequent backpass convective "superheat," "reheat," and |