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Show INTRODUCTION N e\~ England Power Service Company (N EP SCo) and Riley Stoker Corporation (Riley) are ev al ua t i ng advan ced oil and gas burners at New England Powe r Company's Salem Harbor, Unit 4 (Salem Harbor) and Brayton Po i nt , Unit 4 (Brayton Point). These units were designed for cyc l ing operat i on, but are currently operated in a base load mode. The Ri ley, wall-fired units are capable of producing 3,260,000 lb/hr of steam at 955°F with reheat, generating 450 MWe. Figure 1 shows a cross section view of the units as designed. Salem Harbor operates near 10% excess air and has a boiler efficiency about 87%. Brayton Point can operate with 15% fl ue gas recirculation (FGR) for NOx emission control. Excess air is boosted to 15% during FGR operation. Currently both units are equipped with Rodenhuis & Verloop TTL7 (200 x 106 Btu/hr) burners. The burners were designed prior to 1970 and are pre-NSPS(A) technology. Salem Harbor is not currently subject to NOx regulations. Brayton Point, designed in 1969, is restricted to 0.3 lb/106 Btu (234 ppm) NOx emissions. Biased firing and FGR enable Brayton Point to accomplish this. Both units are limited to 0.05 lb/106 Btu particulate emissions and are equipped with electrostatic precipitators for particulate control. Performance goals for the new burners include 0.3 lb/106 Btu of NOx at 5% excess air while maintaining unburned carbon in the flyash to less than 20%. This will reduce total particulate emissions and improves precipitator performance. Fly ash at Salem Harbor currently contains approximately 30% carbon in the flyash. (A)1970 new source performance standards for NOx emission control. (B) All emissions are corrected to 3% O2• AFRC89 2 |