利用硫酸根自由基处理剩余污泥

摘要

The disintegration of excess sludge with sulfate free radical produced by heat-activated potassium persulfate was studied. The changes of the sludge's nature before and after the treatment were investigated. The results indicated that the sludge dissolution ratio displayed a linear decrease with the increase of reaction time. Elevated temperature can improve the efficiency of heat-activated potassium persulfate and the rnsludge disintegration rate. In the following operation condition, reaction temperature of 90℃ , heating time of 90 min and the K2S2O8 dosage of 0. 5 g per gram SS, the sludge dissolution ratio was 16.9%. In this operation, more microbial extracellular polymeric substances (EPS) were decomposed, rnand more intracellular material was released to the liquid phase. The concentration of SCOD was increased to 719 mg/L, which is 435 mg/L by single heating treatment; the concentration of TN, TP was increased by 46% and 60% respectively. Part of organic nitrogen was mineralized by oxidants to NH+4-N, whose concentration was increased from 15. 0 to 27. 8 mg/L.%利用K2S2O8热活化产生具有强氧化性的硫酸根自由基破解剩余污泥,与单独加热相比,考察了处理前后污泥性质的变化.实验结果表明,随着反应时间的增加,污泥分解率呈线性上升趋势,升高温度可提高K2S2O8热活化的效率,增加污泥的破解率.当反应温度90℃、加热时间90 min、每克悬浮固体(SS)中K2S2O8投加量为0.5g时,污泥分解率达16.9％;微生物胞外聚合物(EPS)被分解、胞内物质释放到液相中,使污泥上清液中SCOD由单独加热时的435 mg/L增至719 mg/L;融胞释放的TN、TP质量浓度比单独加热处理分别增加了46％和60％;在高温及氧化剂的作用下,部分有机氮被转化成NH4+-N,使污泥上清液中的NH4+-N质量浓度由15.0 mg/L增至27.8 mg/L.