亚临界水解法处理城市污泥及其栽培试验

摘要

Municipal sludge rich in organic matter, is a kind of important resources. For a long time, due to the lack of efficient processing methods, large quantity of municipal sludges were treated by incineration and landfill. The resources were wasted and the environments were polluted. In this work, municipal sludge samples were collected from Beijing and Tianjin treatment plants. And the samples were treated with sub-critical water pyrolysis technology. Test results showed that the treated municipal sludge was powder, no odor, organic matter content up to 80％, heavy metals well below the national restrictive standards, toxic and harmful substances were not detected. The treated municipal sludge is ideal raw material for the production of organic fertilizer, bio-organic fertilizer and agricultural microbial agents. Further cultivation experiment showed that treated municipal sludge with half dose of chemical fertilizer could save chemical fertilizer, improve the quality of chinese cabbage, and improve soil fertility than single application of chemical fertilizer.%城市生活污泥富含有机质,是一类重要资源.长期以来,由于缺乏高效处理加工技术手段,大量城市污泥被焚烧、填埋,既浪费了资源,又污染环境.本文采集了北京市和天津市污水处理厂的代表性污泥样品,并采用亚临界水解技术进行了处理.研究结果表明,亚临界水解法较好地解决了城市污泥胶粘难以干燥和恶臭问题,保存了污泥中的有机质,同时消除了污泥中的病原,降低了重金属汞含量,是一项处理城市污泥的理想方法;城市污泥水解产物有机物含量高达80%,重金属含量远低于国家限制性标准,未检出有机污染物,蛔虫卵死亡率100%,未检出粪大肠菌群,是生产有机肥料、生物有机肥和农用微生物菌剂的理想原料;栽培试验表明,城市污泥热解产物配施半量化肥比单施全量化肥,可以节省化肥,提高小白菜品质,提高土壤肥力.