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Show busUon 2000 Program has two coinciding engineering development activities that are expected to improve environmental performance and thermal efficiency of future coal-fired power plants: The Low- Emission Boiler System (LEBS) and the High-Perfor-mance Power System (HIPPS). Babcock & Wilcox (B&W). under contract to DOE-PETC and with subcontracts to PSI PowerServe. the Massachusetts Institute of Technology (MIT), and Raytheon Engineers and Constructors (RE&C) has begun development of an advanced low emission boiler system. The work presented in this paper was conducted under the LEBS portion of the Combustion 2000 program. The LEBS workscope calls for the development of a new boiler design equipped with improved combustion and heat transfer subsystems and advanced environmental control technologies capable of achieving emissions of SOx, NOx. and particulates far below current N e w Source Performance Standards (NSPS). The LEBS will use relatively near-term developing technology to lower S02. NOx. and particulate emissions, while keeping the cost of electricity comparable to that of conventional technology. Other objectives include reducing waste generation, producing usable by-products, improving ash disposability. and increasing power plant thermal efficiency. Because more efficient plants use less fuel per unit of electricity produced, an additional benefit of higher efficiency is lower emissions (including C O J on a pound per kilowatt basis. LEBS major goals are: Q X SOx - Less than 0.20 lb/106 Btu S O z firing coal with 3 lb/106 Btu of sulfur Particulate - Less than 0.015 lb/106 Btu of fuel input n j Waste and Air Toxics - Reduced Plant Efficiency - Greater than 3 8 % Commercial Readiness - 2000 or sooner ^*r NOx - Less than 0^€Tlb/106 Btu of fuel input firing on bituminous coal Major system development efforts are required for LEBS to meet these goals. In order to be successful, all major plant subsystems must be Integrated. The new plants need to be designed from the ground up with the new technologies in mind. Therefore, to ensure expertise in a broad range of technical areas. subsystem evaluation teams were formed. These subsystems are illustrated in Figure 1 and Include: 1) N O x control. 2) SOx/Particulates/Alr Toxics/Solid Waste Control. 3) Boiler Island, and 4) Balance-of- Plant. The LEBS program will consist of four phases over 114 months.® The work completed to date under Phase I consists of a thorough assessment of potential advanced technologies and techniques for the control of emissions, and a review of boiler design options. This includes evaluation of various advanced combustion techniques and furnace designs for N O x reduction and numerous near-term advanced flue gas cleanup options for SOx. particulates, air toxics, and solid by-product reduction. EVALUATION OF SUBSYSTEM CONCEPTS The candidate screening process (Figure 2) began with the development of a "long-list" of candidate technologies for the LEBS plant subsystems. The UP^ BALANCE OF PLANT SUBSYSTEMS NOx SUBSYSTEM BOILER SUBSYSTEM Figure 1. Subsystem evaluation teams 2 Paper No. 11-13 |