Ping Chen , Cheng Gong , Mingyan Gu , Kun Luo , Jianren Fan
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引用次数: 0
Abstract
Ammonia-coal co-combustion can significantly reduce CO2 emissions from pulverized coal boiler. However, since ammonia is a blended high-nitrogen fuel, an inevitably increases the risk of high NOx emissions. Therefore, in-depth research on the transformation path of fuel-N during ammonia-coal co-combustion is the key to achieving low-nitrogen combustion. Since naturally occurring minerals in coal impact the migration and transformation of fuel-N, we report an experimental study coupled with quantum chemistry calculations to study the generation of nitrogen oxides during ammonia-coal co-combustion, in the presence of the inherent mineral Fe. The experimental results showed that under all the temperatures and ammonia co-firing ratios studied in this work, ammonia-coupled Fe-impregnated pulverized coal inhibited NO generation compared to coal without Fe impregnation. Theoretical calculations provided the possible existing forms of Fe in this system, and revealed the molecular pathways for the oxidation of ammonia-N to the nitrogen-containing intermediates of HNO and NCO, as influenced by the presence of mineral Fe. It was found that with impregnated Fe, the activation energy of the rate-determining step for the oxidation of fuel-N was about 30–40 kJ/mol higher than that without Fe impregnation; thus, Fe reduced the oxidation rate of fuel-N. The theoretical calculations elaborated the mechanism of the inhibited generation of nitrogen oxides with mineral Fe. The results indicated the enhancement of binding energy between nitrogen products and the surface of coal char.
期刊介绍:
The mission of the journal is to publish high quality work from experimental, theoretical, and computational investigations on the fundamentals of combustion phenomena and closely allied matters. While submissions in all pertinent areas are welcomed, past and recent focus of the journal has been on:
Development and validation of reaction kinetics, reduction of reaction mechanisms and modeling of combustion systems, including:
Conventional, alternative and surrogate fuels;
Pollutants;
Particulate and aerosol formation and abatement;
Heterogeneous processes.
Experimental, theoretical, and computational studies of laminar and turbulent combustion phenomena, including:
Premixed and non-premixed flames;
Ignition and extinction phenomena;
Flame propagation;
Flame structure;
Instabilities and swirl;
Flame spread;
Multi-phase reactants.
Advances in diagnostic and computational methods in combustion, including:
Measurement and simulation of scalar and vector properties;
Novel techniques;
State-of-the art applications.
Fundamental investigations of combustion technologies and systems, including:
Internal combustion engines;
Gas turbines;
Small- and large-scale stationary combustion and power generation;
Catalytic combustion;
Combustion synthesis;
Combustion under extreme conditions;
New concepts.