蒸汽加热法去除烟气白雾技术

Technology of steam heating method to removal gas fog

石灰石-石膏湿法脱硫烟囱出口形成的白雾现象,不仅影响视觉效果,还会影响污染物的扩散效果。湿法脱硫装置后的烟气具有腐蚀性强,含水量高,温度低的特点,使得蒸汽-烟气换热器腐蚀较快,体积大,蒸汽耗量大。对比了几种消除白雾的措施,从材料耐腐蚀性、换热管的形式、换热蒸汽的选用几方面对蒸汽加热技术进行研究,并在工程应用中进行验证。蒸汽-烟气换热器的换热管使用SAF2205高频焊管,将锅炉省煤器常用的H型翅片换热管应用于除白雾蒸汽换热器,并采用中低温低压饱和蒸汽提供热源,提高了换热效率,减少了蒸汽耗量,在工程应用中取得了较好的效果。加热后的烟温达到82℃,有效去除了烟囱的白雾。

The phenomenon of white mist occurs at the outlet of the chimney for limestone-gypsum wet desulfurization not only influences the visual effect, but also affects the diffusion effect of contaminants. Smokes emitted from the wet desulfurization unit were with strong corrosive, high moisture contents and low temperature properties that is easy causing the corrosion on steam-smoke heat exchanger quickly and increase the volume and high steam consumption. In this paper, a number of measures for the removal of white mist were compared, and researches were carried out on steam heating technology in service aspects of corrosion resistance of materials, types of heat exchangers and selection of steam for heat exchanging and validated in engineering application. SAF2205 high frequency welded pipe is used as a tube for steam-smoke heat exchanger proposed herein, H-shaped finned heat exchanger tubes commonly used in the coal saver for boilers are applied in steam heat exchanger for the elimination of white mist, and medium temperature. Low pressure saturated steam is used to offer heat sources to increase heat exchanger efficiency and reduce steam consumption which achieves better effects in engineering application. The temperature of heated smokes reaches 82℃, so that white mist from the chimney is removed effectively.