烧结烟气采用湿法脱硫烟气再热问题研究

Research on gas reheating technology of sinter flue gas processed by wet desulfurization

烧结烟气经湿法脱硫处理后净烟气温度为45~55℃,净烟气中含有微量机械水和饱和水蒸气,净烟气直接送入烟囱排放,由于烟温较低烟气抬升高度有限,影响烟气中污染物的扩散净化,造成附近地区污染物聚集;净烟气经过烟囱散热,饱和水蒸气迅速凝结,形成大量烟羽(白雾)现象,造成视觉污染。本文通过利用烟气饱和温度-含湿量曲线分析,得出环境温度越低、含湿量越大、饱和烟气初始温度越高,净烟气加热温差越大;通过分析净烟气再热技术并指出各种再热技术的优缺点,为烧结烟气湿法脱硫净烟气再热改造提供技术参考。

The temperature of sintering flue gas processed by wet desulfurization is between 45 - 55℃. Purified flue gas contains small liquid water droplets and saturated steam. The gas directly discharge into the enviromnent without reheating causes low lifting height and pollutant accumulation in near area, for the low temperature of purified gas. And the heat loss by the stack wall, causes condensation of saturated water vapor rapidly, which forms a large number of plume （fog） phenomenon and causes visual pollution. In this paper, by analysing the flue gas saturation temperature-humidity curve, this reserch shows that the lower temperature and moisture content of the ambient environment, the higher temperature of initial saturated gas, and the greater temperature difference of reheating flue gas. In addition, by analysing the purified flue gas reheating technology and pointing out the advantages and disadvantages of each reheat technology, it can provide technical references for reheating sintering flue gas treated by wet desulfurization.