Pilot-scale evaluation of reburning for cyclone-boiler NOx control. Final report, May 1987-April 1990

Technical Report · Sun Apr 01 04:00:00 EDT 1990

OSTI ID:6751499

Farzan, H; Maringo, G J

There are currently no commercially-demonstrated combustion modification techniques for cyclone boilers which reduce NOx emissions. The emerging reburning technology offers cyclone boiler owners a promising alternative to expensive flue gas cleanup techniques for NOx emission reduction. Reburning involves the injection of a supplemental fuel (natural gas, oil, or coal) into the main furnace in order to produce locally reducing stoichiometric conditions that convert NOx produced in the main combustion zone to molecular nitrogen, thereby reducing overall NOx emissions. The report presents the encouraging pilot-scale results obtained using natural gas, fuel oil, and pulverized coal (PC) as reburning fuels. At a reburning zone stoichiometry of 0.9, 67% NOx reduction for gas and oil reburning and 57% for coal reburning were achieved. Flue gas recirculation (FGR) was introduced at the reburn burners, and improved mixing and NOx reduction. FGR was more effective with PC reburning. Carbon monoxide (CO) emissions levels were low (less than 30 ppm) throughout the various optimum test conditions. Although the carbon content of the fly ash increased, the overall combustion efficiencies were insignificantly lower for all the reburning fuels. Furnace exit gas temperatures (FEGTs) increased by less than 50 F during reburning operation. Capital costs for reburn technology on a 200-MW cyclone-fired unit can range from about $22/kW (gas) to $41/kW (coal). Ten-year levelized incremental busbar costs were sensitive to assumed reburning fuel prices. Lower projections were 1.7 mills/kWh (coal), 2.3 mills/kWh (gas), and 3.3 mills/kWh (oil).

• Research Organization: Babcock and Wilcox Co., Alliance, OH (USA). Research and Development Div.
• OSTI ID: 6751499
• Report Number(s): PB-90-228057/XAB
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800 -- Coal
Lignite
& Peat-- Waste Management
014000 -- Coal
Lignite
& Peat-- Combustion
02 PETROLEUM
020800 -- Petroleum-- Waste Management
025000 -- Petroleum-- Combustion
03 NATURAL GAS
030700 -- Natural Gas-- Waste Management
034000 -- Natural Gas-- Combustion
20 FOSSIL-FUELED POWER PLANTS
200202* -- Fossil-Fueled Power Plants-- Waste Management-- Noxious Gas & Particulate Emissions
AEROSOL WASTES
AIR POLLUTION ABATEMENT
ASHES
BOILERS
BURNERS
CAPITALIZED COST
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL REACTIONS
COAL
COMBUSTION
COMBUSTORS
COST
CYCLONE COMBUSTORS
DOCUMENT TYPES
EFFICIENCY
ELEMENTS
ENERGY SOURCES
EQUIPMENT
FLUE GAS
FLUIDS
FLY ASH
FOSSIL FUELS
FOSSIL-FUEL POWER PLANTS
FUEL GAS
FUEL OILS
FUELS
FUNCTIONAL MODELS
GAS FUELS
GASEOUS WASTES
GASES
LIQUID FUELS
MATERIALS
MODIFICATIONS
NATURAL GAS
NITROGEN
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PETROLEUM PRODUCTS
PILOT PLANTS
POLLUTION ABATEMENT
POLLUTION CONTROL EQUIPMENT
POWER PLANTS
PROGRESS REPORT
PULVERIZED FUELS
RECYCLING
RESIDUES
STOICHIOMETRY
TEMPERATURE MEASUREMENT
THERMAL POWER PLANTS
THERMOCHEMICAL PROCESSES
WASTES