Mechanisms of nitrous oxide formation in coal flames

Journal Article · Fri Sep 01 04:00:00 EDT 1989 · Combustion and Flame; (USA)

DOI:https://doi.org/10.1016/0010-2180(89)90142-9· OSTI ID:5532401

Kramlich, J C; Cole, J A; McCarthy, J M; Lanier, W S ^[1]; McSorley, J A ^[2]

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1. Energy and Environmental Research Corp., Irvine, CA (USA)
2. Air and Engineering Research Lab., U.S. Environmental Protection Agency, Research Triangle Park, NC (US)

Significant nitrous oxide (N/sub 2/O) emissions have been observed from coal and oil burning power plants, but not from industrial gas flames, even when they are doped with an equivalent amount of fuel nitrogen. The unknown mechanism by which this N/sub 2/O forms has considerable importance in determining the influence of common and advanced nitrogen oxide (NO/sub x/) control strategies on N/sub 2/O. The present study uses both detailed kinetic modeling and plug-flow simulator experiments to investigate this mechanism. Kinetic modeling suggests that net N/sub 2/O is unlikely to form within flame zones because of its rapid removal by N/sub 2/O + H {yields}N/sub 2/ + OH. Also reduction of nitric oxide (NO) on coal char can be a significant N/sub 2/O source only if the rates are many times their published values. However, both kinetic modeling and experiments show that if HCN appears in the gas phase between 1150 and 1500 K it will be partially converted to N/sub 2/O. The source of HCN may be either direct devolatilization, or a char gasification reaction. This suggests that the N/sub 2/O that appears in coal flames may originate from the homogeneous reaction of devolatilized char nitrogen in the fuel-lean postflame region.

• OSTI ID: 5532401
• Journal Information: Combustion and Flame; (USA), Journal Name: Combustion and Flame; (USA) Vol. 77:3; ISSN CBFMA; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

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014000 -- Coal
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& Peat-- Combustion
20 FOSSIL-FUELED POWER PLANTS
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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800 -- Combustion
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500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION CONTROL
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHARS
CHEMICAL REACTION KINETICS
COAL
COMBUSTION KINETICS
CONTROL
EMISSION
ENERGY SOURCES
ENVIRONMENTAL EFFECTS
FLAMES
FLUIDS
FOSSIL FUELS
FOSSIL-FUEL POWER PLANTS
FUELS
GASES
KINETICS
MATERIALS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NITROUS OXIDE
OXIDES
OXYGEN COMPOUNDS
PETROLEUM
POLLUTION CONTROL
POWER PLANTS
PYROLYSIS PRODUCTS
REACTION KINETICS
THERMAL POWER PLANTS