Low-NOx burner and SNCR retrofit experience at New England Power Salem Harbor Station

Technical Report · Mon Jan 01 04:00:00 EST 1996

OSTI ID:269425

Quartucy, G ^[1]; Sload, A; Fynan, G; Afonso, R ^[2]

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1. Fossil Energy Research Corp., Laguna Hills, CA (United States)
2. New England Power Co., Westborough, MA (United States)

New England Power has recently installed Riley-Stoker low-NO{sub x} burners (LNB) and Nalco Fuel Tech urea-based selective non-catalytic NO{sub x} reduction (SNCR) systems on Units 1 and 3 at its Salem Harbor generating station. In addition, Unit 3 was also retrofit with a two-level overfire air (OFA) system. These two coal-fired units are front wall-fired with unequal burner spacing and have uncontrolled full-load NO{sub x} emissions of nominally 750 ppm (1.1 lb/MMBtu). Unit 1 is rated at 86 MW and has 12 burners, while Unit 3 is rated at 155 MW and has 16 burners. NO{sub x} reduction performance of the LNB, OFA and SNCR systems has been characterized both independently and in combination during the test programs while firing low-sulfur coals. Unit 1 tests showed that the LNBs provided NO{sub x} reductions of approximately 50 percent at loads above 60 MW using narrow angle coal spreaders. Corresponding ash carbon at these NO{sub x} levels varied between 16 and 35 percent. The SNCR system provided an additional 40 percent NO{sub x} reduction from the LNB baseline at a molar N/NO ratio of 1.2. The corresponding NH{sub 3} slip levels were less than 10 ppm. On Unit 3, LNB tests showed that NO{sub x} reductions of nominally 10 percent were achieved with the burners alone, using wide angle coal spreaders. The use of OFA, at design levels, provided additional NO{sub x} reductions ranging from 42 percent at full load to 4 percent a minimum load relative to the LNB baseline. Ash carbon levels doubled to levels above 30 percent when the OFA system was operated at design conditions at loads above 110 MW. The SNCR system provided NO{sub x} reductions of 33 percent relative to the LNB/OFA baseline of 0.55 lb/MMBtu, at a molar N/NO ratio of 1.3. Ammonia slip for these conditions was less than 5 ppm.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 269425
• Report Number(s): EPRI-TR--105978-V1; CONF-9505150--Vol.1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
AIR POLLUTION CONTROL
BURNERS
COAL
COMBUSTION
EMISSION
FOSSIL-FUEL POWER PLANTS
NITROGEN OXIDES
PERFORMANCE
RETROFITTING
SELECTIVE CATALYTIC REDUCTION