声学技术在炉内NO_x消减中的应用研究

发布时间：2018-05-05 20:17

本文选题：声学测温 + NO_x消减　；参考：《华北电力大学(北京)》2014年硕士论文

【摘要】：近年来,随着国内经济的快速发展,氮氧化物(NOx)的排放量迅速增加,严重污染了生态环境,已成为制约社会经济发展的重要因素之一。火电厂因其NOx排放量大且相对集中、较其他分散源容易控制,成为国家控制NOx排放的首选目标,因此脱硝成为火电企业“十二五”期间必须完成好的节能减排任务。本文从燃煤锅炉NOx控制消减的角度出发,基于本课题组声学技术的特色优势,一方面将声学测温技术与炉内SNCR脱硝系统相结合,选取实例在fluent模拟的基础上,采取合适的声学测温装置布置,进行最优温度窗口的确定以及SNCR喷氨的设计,基于声学测温的炉膛SNCR脱硝的喷氨设计综合考虑了温度窗口和炉膛结构因素,设计方案合理且可行,在提高脱硝效率,减少氨逃逸等问题上具有积极的作用,为SNCR的优化提供了切实可行的方案；另一方面自行设计搭建煤粉燃烧实验台,对声波助燃现象,声波降低NOx生成的影响效果进行了理论论述和实验研究,着重探究了不同声波频率,声压值对NOx生成的影响规律,实验结果证明了声波对煤粉燃烧的促进作用,同时煤粉在声场下的燃烧可以一定程度的降低NOx的生成,作用最明显的区域在风粉混合燃烧段。在实验条件下,相对低频(200Hz)的和高声压(120dB)的声波,对NOx的降低效果更突出。此次实验可以为理论的验证起到参考作用,为实际的燃烧进行一定的指导。
[Abstract]:In recent years, with the rapid development of domestic economy, the emission of no _ x has increased rapidly, which has seriously polluted the ecological environment, and has become one of the important factors restricting the development of social economy. Because the NOx emission of thermal power plant is large and relatively concentrated, it is easier to control than other dispersive sources, so denitrification has become the first choice of the state to control NOx emissions, so denitrification has become a good task of energy saving and emission reduction for thermal power enterprises during the 12th Five-Year Plan period. In this paper, from the point of view of NOx control and subtraction of coal-fired boiler, based on the characteristic advantages of acoustics technology in our group, on the one hand, the acoustical temperature measurement technology is combined with SNCR denitrification system in furnace, and an example is selected on the basis of fluent simulation. The optimum temperature window and the design of SNCR ammonia injection are determined by adopting the appropriate arrangement of acoustic temperature measuring device. The ammonia injection design of SNCR denitrification in furnace based on acoustic temperature measurement takes into account the temperature window and furnace structure factors. The design scheme is reasonable and feasible, which plays an active role in improving denitrification efficiency and reducing ammonia escape, which provides a feasible scheme for the optimization of SNCR. On the other hand, the experimental bench of pulverized coal combustion is designed and built by ourselves to support the phenomenon of acoustic wave combustion. In this paper, the influence of acoustic wave on the formation of NOx is discussed theoretically and experimentally. The influence of different frequency and pressure of sound wave on the formation of NOx is discussed. The experimental results show that the effect of acoustic wave on the combustion of pulverized coal is promoted. At the same time, the combustion of pulverized coal in the sound field can reduce the formation of NOx to a certain extent, the most obvious role of the area in the air-powder combustion section. Under the experimental conditions, the reduction of NOx by the acoustic waves of relative low frequency (200Hz) and hypersonic pressure (120dB) is more prominent. This experiment can serve as a reference for theoretical verification and guide the actual combustion.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：X773

【参考文献】