市政污泥干化焚烧处理技术探究

Research on Drying and Incineration Treatment Process of Municipal Sludge

市政污泥含有重金属、化学污染物、有机质以及多种病原体,常规处理方式的缺点为成本高、水资源消耗大,干化焚烧工艺经过脱水和高温焚烧两道工序,能够大幅降低污泥中污染物的含量。为了探究该工艺技术的应用方法,研究过程分别开展干化实验和焚烧实验,确定含水率、有机质含量、干化温度的合理取值范围,对焚烧残渣中的重金属元素进行分析,进而在此基础上设计出干化焚烧处理工艺系统。经过实测,锌、铅、镍、砼、总铬、六价铬的浓度分别为0.02、0.01、0.005、0.01、0.01、0.003 mg/L,远低于国家标准规定的限值,说明系统在残渣处理方面表现出较高的环保性。此外,针对烟气排放的检测结果显示:颗粒物、SO_(x)、NO_(x)、CO、二噁英的排放浓度分别为9.4、0.7、100.6、5.6、0.04 mg/Nm 3,不仅低于国家标准,同时也低于欧盟标准,达到了优异的控制效果,表明系统在烟气排放方面具有良好的环保性能。

Municipal sludge contains heavy metals,chemical pollutants,organic matter,and various pathogens.The disadvantages of conventional treatment methods are high cost and high-water resource consumption.The drying and incineration process,which involves dehydration and high-temperature incineration,can significantly reduce the content of pollutants in sludge.In order to explore the application methods of this technology,drying experiments and incineration experiments were carried out during the research process to determine the reasonable range of moisture content,organic matter content,and drying temperature.The heavy metal elements in the incineration residue were analyzed.Based on this,a drying and incineration treatment process system was designed.After actual testing,the concentrations of zinc,lead,nickel,concrete,total chromium,and hexavalent chromium were 0.02,0.01,0.005,0.01,0.01,and 0.003 mg/L,respectively,which were far below the limit values specified in national standards,indicating that the system has shown high environmental friendliness in residue treatment.In addition,the detection results for smoke emissions show that the emission concentrations of particulate matter,SO_(x),NO_(x),CO,and dioxins are 9.4,0.7,100.6,5.6,and 0.04 mg/Nm 3,respectively,which are not only lower than the national standard but also lower than the EU standard,achieving excellent control effects,indicating that the system has good environmental performance in smoke emissions.