超临界水氧化后生活垃圾中元素的迁移规律

Elemental Migration Mechanism of Domestic Waste Treated by Supercritical Water Oxidation

采用超临界水氧化处理垃圾的方式,对生活垃圾中C、N、S元素的迁移规律进行了研究.结果表明：随着温度的升高,气相产物碳收率增加,固相产物碳收率降低,液相产物碳收率基本稳定;NO、NO2、NH3及HCN产气氮收率均接近0,有一部分N元素转化为N2O气体;有5%-30%的硫元素以硫酸盐的形式存在于液相中,几乎不产生SO2、SO3气体.同时,添加活性炭既能促进氧化反应又可降低N2O气体的生成.

Domestic waste was treated by supercritical water oxidation （SCWO） and elemental migration mechanisms of carbon, nitrogen and sulfur were investigated. Results show carbonous yield increases in gas productions, decreases in solid residues and keeps stable in liquid products with increasing temperature. Nitrous yields of NO, NO2, NH3 and HCN are close to zero, and a part of nitrogen is converted into nitrous oxide. 5 %-30% of sulfur is kept in liquid phase as a form of sulfate, and emissions of SO2 and SO3 approximate to zero. Experiments find that activated carbon additive can not only enhance oxidation but also reduce N2O yield.