684 / 2019-04-30 11:47:15

Study on Influencing Factors of NOx Reduction by Pyrolysis Gas in Fluidized Combustion

Denitrification, Pyrolysis Gas, Additive, Fluidized Bed

全体主题 > 环境保护

As the operational load of fluidized bed boilers varies greatly, and the selective non-catalytic reduction denitrification technology is limited by the reaction temperature window and is faced with the problems of low reaction rate and high ammonia escape rate, coal pyrolysis gas was used to reduce NOx into N2 in a circulating fluidized bed system this work. The influences of ammonia/nitrogen molar ratio (NSR), reaction residence time, and additive concentration on the denitrification reduction reaction were studied through experiments and elemental reaction simulation calculation. The results show that the concentration of pyrolysis gas has a weak synergistic effect with the residence time, and forms a strong synergistic effect with the NSR. As the concentration of pyrolysis gas increases, the effect of NSR on the reduction reaction gradually strengthens, and the ammonia agent required to achieve the same denitration efficiency can be reduced. Although pyrolysis gas cannot completely replace ammonia reductant in terms of NOx removal rate, the presence of pyrolysis gas can speed up the reaction rate and shorten the reaction residence time within a certain range, and at the same time allow the appropriate reduction of NSR and reduce the ammonia escape.