Abstract
The subject of this thesis is the use of Selective Noncatalytic Reduction (SNR) of nitrogen oxides from combustion by direct injection of a reductant into the post-combustion zone of the combustor. Pilot-scale experiments with either urea of ammonia as reductant are described. The use of an additive for widening the temperature window of the process has been tested. Full-scale optimization of the process with ammonia as reductant and natural gas as additive has been performed. Both ammonia and urea reductants had the same reducing effect, although the optimum temperatures were different. In the case of urea, a significant emission of N{sub 2}O was seen, maximum 82 ppm at 950 deg. C. In the case of ammonia as the main reductant, 16 additives, chosen among hydrocarbons, alcohols, and amines, has been tested for their capabilities of widening the temperature window of the process. Most of them were capable only of moving the window downwards. Natural gas, is capable of reducing the emission of unburnt ammonia, which is not seen with methane. Natural gas has effect only together with ammonia. No single effect of gas injection was seen. Injection of natural gas downstream of the ammonia injection point led to a 60-70%
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Citation Formats
Joedal, M.
SNR optimization. Optimization of selective noncatalytic reduction of nitrogen oxides from coal burning systems by direct injection of a reductant into the post-combustion zone of the combustor; SNR-optimering. Optimering af selektiv nonkatalytisk reduktion af kvaelstofoxider fra kulforbraendingsanlaeg ved brug af additiver til primaerreduktionsmidlet.
Denmark: N. p.,
1991.
Web.
Joedal, M.
SNR optimization. Optimization of selective noncatalytic reduction of nitrogen oxides from coal burning systems by direct injection of a reductant into the post-combustion zone of the combustor; SNR-optimering. Optimering af selektiv nonkatalytisk reduktion af kvaelstofoxider fra kulforbraendingsanlaeg ved brug af additiver til primaerreduktionsmidlet.
Denmark.
Joedal, M.
1991.
"SNR optimization. Optimization of selective noncatalytic reduction of nitrogen oxides from coal burning systems by direct injection of a reductant into the post-combustion zone of the combustor; SNR-optimering. Optimering af selektiv nonkatalytisk reduktion af kvaelstofoxider fra kulforbraendingsanlaeg ved brug af additiver til primaerreduktionsmidlet."
Denmark.
@misc{etde_10133748,
title = {SNR optimization. Optimization of selective noncatalytic reduction of nitrogen oxides from coal burning systems by direct injection of a reductant into the post-combustion zone of the combustor; SNR-optimering. Optimering af selektiv nonkatalytisk reduktion af kvaelstofoxider fra kulforbraendingsanlaeg ved brug af additiver til primaerreduktionsmidlet}
author = {Joedal, M}
abstractNote = {The subject of this thesis is the use of Selective Noncatalytic Reduction (SNR) of nitrogen oxides from combustion by direct injection of a reductant into the post-combustion zone of the combustor. Pilot-scale experiments with either urea of ammonia as reductant are described. The use of an additive for widening the temperature window of the process has been tested. Full-scale optimization of the process with ammonia as reductant and natural gas as additive has been performed. Both ammonia and urea reductants had the same reducing effect, although the optimum temperatures were different. In the case of urea, a significant emission of N{sub 2}O was seen, maximum 82 ppm at 950 deg. C. In the case of ammonia as the main reductant, 16 additives, chosen among hydrocarbons, alcohols, and amines, has been tested for their capabilities of widening the temperature window of the process. Most of them were capable only of moving the window downwards. Natural gas, is capable of reducing the emission of unburnt ammonia, which is not seen with methane. Natural gas has effect only together with ammonia. No single effect of gas injection was seen. Injection of natural gas downstream of the ammonia injection point led to a 60-70% reduction of ammonia slip, with no effect on the NO reduction. (AB) 101 refs.}
place = {Denmark}
year = {1991}
month = {Jul}
}
title = {SNR optimization. Optimization of selective noncatalytic reduction of nitrogen oxides from coal burning systems by direct injection of a reductant into the post-combustion zone of the combustor; SNR-optimering. Optimering af selektiv nonkatalytisk reduktion af kvaelstofoxider fra kulforbraendingsanlaeg ved brug af additiver til primaerreduktionsmidlet}
author = {Joedal, M}
abstractNote = {The subject of this thesis is the use of Selective Noncatalytic Reduction (SNR) of nitrogen oxides from combustion by direct injection of a reductant into the post-combustion zone of the combustor. Pilot-scale experiments with either urea of ammonia as reductant are described. The use of an additive for widening the temperature window of the process has been tested. Full-scale optimization of the process with ammonia as reductant and natural gas as additive has been performed. Both ammonia and urea reductants had the same reducing effect, although the optimum temperatures were different. In the case of urea, a significant emission of N{sub 2}O was seen, maximum 82 ppm at 950 deg. C. In the case of ammonia as the main reductant, 16 additives, chosen among hydrocarbons, alcohols, and amines, has been tested for their capabilities of widening the temperature window of the process. Most of them were capable only of moving the window downwards. Natural gas, is capable of reducing the emission of unburnt ammonia, which is not seen with methane. Natural gas has effect only together with ammonia. No single effect of gas injection was seen. Injection of natural gas downstream of the ammonia injection point led to a 60-70% reduction of ammonia slip, with no effect on the NO reduction. (AB) 101 refs.}
place = {Denmark}
year = {1991}
month = {Jul}
}