燃煤电厂SO_(3)在线监测烟气预处理方法

Flue gas pretreatment method for SO_(3) on-line monitoring in coal fired power plant

燃煤电厂烟气排放连续监测系统(CEMS)尚未有效的SO_(3)浓度在线监测方法,烟气SO_(3)主要包含气态SO_(3)、硫酸雾和附着在颗粒物表面的SO_(3)结晶。为了实现排放烟气SO_(3)浓度在线监测,设计了SO_(2)与SO_(3)融合检测方法,解决了SO_(3)与SO_(2)吸收光谱重合的问题,发明了烟气制冷水吸收加热后测量硫酸浓度的SO_(3)在线监测预处理方法,对预处理方法进行实验分析,制冷吸收法的SO_(2)吸收效率为60.62%。加热制冷吸收液后的体积为加热前体积一半时,加热溶液中硫酸的含量降低为加热前的92.7%,溶液中亚硫酸溶液的含量降低为加热前的21.3%,最终得到了烟气SO_(3)实时浓度计算公式。

The continuous monitoring system for flue gas emissions(CEMS)of coal-fired power plants had not yet been an effective on-line monitoring method for SO_(3) concentration.Flue gas SO_(3) mainly included gaseous SO_(3),sulfuric acid mist and SO_(3) crystals attached to the surface of particulate matter.In order to realize on-line monitoring of SO_(3) concentration in flue gas,the SO_(2) and SO_(3) fusion detection method was designed to solve the problem of the overlap of the absorption spectra of SO_(3) and SO_(2),and the measurement after the absorption and heating of the flue gas cooling water was invented.The SO_(3) on-line monitoring pretreatment method of sulfuric acid concentration,the experimental analysis of the pretreatment method,the SO_(2) absorption efficiency of the refrigeration absorption method was 60.62%.When the volume of the heated and refrigerated absorption liquid was half of the volume before heating,the content of sulfuric acid in the heated solution was reduced to 92.7%of that before heating,and the content of sulfurous acid solution in the solution was reduced to 21.3%of that before heating.Finally,the formula for calculating the real-time concentration of flue gas SO_(3) was obtained.