温度和含水率对村镇垃圾焚烧烟气中有机物排放的影响

The influence of temperature and moisture content on the release of organic pollutants in flue gas of rural solid waste (RSW) incineration

使用管式炉模拟村镇生活垃圾焚烧过程,研究不同焚烧温度和不同垃圾含水率条件下,村镇垃圾焚烧烟气中多环芳烃(PAHs)、氯苯及苯系物的生成和分布特性.结果表明,焚烧温度为550℃时,烟气中多环芳烃和氯苯的释放量最大,当温度小于550℃时,多环芳烃和氯苯的释放量随温度升高而增加,温度大于550℃时,多环芳烃和氯苯的释放量随温度升高而降低.高温焚烧不仅可以抑制烟气中多环芳烃的浓度及减少大分子量PAHs的排放,还能降低氯苯的释放量和氯代数,从而减小村镇垃圾焚烧烟气中的毒性;苯系物随着温度升高,由热解转变为高温合成,释放量也随着增加.水分对多环芳烃和氯苯有较大影响,对苯系物的影响较小.在400℃条件焚烧时,水分含量对多环芳烃总体上是促进的,而在850℃焚烧条件下则表现出抑制作用;而水分对氯苯则均表现出抑制作用,并且可以降低氯苯化合物的氯代数.

The release and distribution characteristics of polycyclic aromatic hydrocarbons(PAHs),chlorobenzene and benzene series in the flue gas of rural solid waste(RSW)incineration were studied under the different temperatures and moisture content conditions.The results showed that when the incineration temperature was less than and more than 550℃,the total release of PAHs and chlorobenzene in flue gas showed a trend of increase and decrease,respectively with increasing of the incineration.The release amount reached the maximum when the temperature rose to 550℃.High temperature incineration of RSW could not only reduce the release concentration of PAHs and the generation of PAHs with large molecular weight in flue gas,but also reduce the release amount of chlorobenzene and chlorine algebra.Thus,the toxicity of RSW incineration flue gas was effectively reduced.With the increase of temperature,the benzene series changed from pyrolysis to high-temperature synthesis,and the release amount also increased.Moisture content had a greater influence on the release of PAHs and chlorobenzene in the flue gas than the release of benzene series.When the incineration temperature was at 400℃ and 850℃,the moisture content promoted and inhibited the release of PAHs on the whole,respectively.The moisture content of RSW showed inhibitory effect on chlorobenzene,and could reduce chlorobenzene compound chlorine algebra.