A kinetic study of NO formation during oxy-fuel combustion of pyridine

The article considers the role and place of water and water vapor in combustion processes with the purpose of reduction the effluents of nitrogen oxides and carbon oxide. We have carried out the complex of theoretical and computational researches on reduction of harmful nitrogen and carbon oxides by gas fuel combustion in dependence on humidity of atmospheric air by two approaches: CFD modeling with attraction of DRM 19 chemical kinetics mechanism of combustion for 19 components along with Bowman’s mechanism used as “postprocessor” to determine the [NO] concentration; different thermodynamic models of predicting the nitrogen oxides NO formation. The numerical simulation of the transport processes for momentum, mass and heat being solved simultaneously in the united equations’ system with the chemical kinetics equations in frame of GRI methane combustion mechanism and NO formation calculated afterwards as “postprocessor” allow calculating the absolute actual [CO] and [NO] concentrations in dependence on combustion operative conditions and on design of furnace facilities. Prediction in frame of thermodynamic equilibrium state for combustion products ensures only evaluation of the relative value of [NO] concentration by wet combustion the gas with humid air regarding that in case of dry air – oxidant. We have developed the methodology and have revealed the results of numerical simulation of impact of the relative humidity of atmospheric air on harmful gases formation. Range of relative air humidity under calculations of atmospheric air under impact on [NO] and [CO] concentrations at the furnace chamber exit makes φ = 0 – 100%. The results of CFD modeling have been verified both by author’s experimental data and due comparing with the trends stated in world literature. We have carried out the complex of the experimental investigations regarding atmospheric air humidification impact on flame structure and environmental characteristics at natural gas combustion with premixed flame formation in open air. The article also proposes the methodology for evaluation of the nitrogen oxides formation in dependence on moisture content of burning mixture. The results of measurements have been used for verification the calculation data. Coincidence of relative change the NO (NOx) yield due humidification the combustion air revealed by means of CFD prediction has confirmed the qualitative and the quantitative correspondence of physical and chemical kinetics mechanisms and the CFD modeling procedures with the processes to be studied. A sharp, more than an order of reduction in NO emissions and simultaneously approximately a two-fold decrease in the CO concentration during combustion of the methane-air mixture under conditions of humidification of the combustion air to a saturation state at a temperature of 325 K.

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Low Heating Value Fuel Combustion: Flamelet Combustion and NO Formation Models

Journal of Propulsion and Power ◽

10.2514/1.8914 ◽

2006 ◽

Vol 22 (1) ◽

pp. 136-144

Author(s):

Takahisa Yamamoto ◽

Tomohiko Furuhata

Keyword(s):

Fuel Combustion ◽

Heating Value ◽

No Formation

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Oxy-fuel combustion of millimeter-sized coal char: Particle temperatures and NO formation

Fuel ◽

10.1016/j.fuel.2013.01.017 ◽

2013 ◽

Vol 106 ◽

pp. 72-78 ◽

Cited By ~ 16

Author(s):

Jacob Brix ◽

Leyre Gómez Navascués ◽

Joachim Bachmann Nielsen ◽

Peter Løvengreen Bonnek ◽

Henning Engelbrecht Larsen ◽

...

Keyword(s):

Fuel Combustion ◽

Coal Char ◽

No Formation ◽

Char Particle

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Highly Time-Resolved Imaging of Combustion and Pyrolysis Product Concentrations in Solid Fuel Combustion: NO Formation in a Burning Cigarette

Analytical Chemistry ◽

10.1021/ac503512a ◽

2015 ◽

Vol 87 (3) ◽

pp. 1711-1717 ◽

Cited By ~ 10

Author(s):

Ralf Zimmermann ◽

Romy Hertz-Schünemann ◽

Sven Ehlert ◽

Chuan Liu ◽

Kevin McAdam ◽

...

Keyword(s):

Solid Fuel ◽

Pyrolysis Product ◽

Fuel Combustion ◽

Time Resolved ◽

No Formation ◽

Solid Fuel Combustion ◽

Time Resolved Imaging

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Reduction behavior of Tin-containing phase in Tin-bearing iron concentrates under CO-CO2 mixed gases

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb181121025y ◽

2019 ◽

Vol 55 (2) ◽

pp. 177-185 ◽

Cited By ~ 1

Author(s):

Y. Yu ◽

H.-J. Li ◽

L. Li

Keyword(s):

Activation Energy ◽

Chemical Analysis ◽

Kinetic Study ◽

Reduction Behavior ◽

No Formation ◽

Roasting Temperature ◽

The One ◽

Mixed Gases

The main purpose of this study was to ascertain the reduction behavior of tin phase (SnO2) in tin-bearing iron concentrates at the respective temperature of 1273 and 1373 K in diverse CO-CO2 mixed gases using chemical analysis, XRD, and SEMEDS analysis. The results show that the reduction behavior of SnO2 depends on the roasting temperature and CO content. At 1273 K, the SnO2 will be reduced to Sn (l) with the CO content being higher than 17.26 vol%, and there is no formation of SnO(s). With the temperature increased to 1373 K, the SnO2 is reduced stepwise in the order to form SnO2 ? SnO (l) ? Sn(l) with CO content over 15.75 vol%. The kinetic study shows that activation energy of the reaction SnO2(s)+CO(g)=Sn(l)+ CO2(g) is 144.75 kJ/mol at 1073-1223 K, being far lower than the one in the reduction of SnO2(s) into SnO(g) at 1273-1323 K, which leads to a conclusion that the tin in tin-bearing iron concentrates could be removed effectively after the Sn(l) sulfurated into SnS at relatively lower temperatures (1073-1223 K) using the sulfidation roasting method.

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