不同生态床对剩余污泥脱水和稳定化的影响  

Dewatering and Stability of Thickened Municipal Sludge Treated in Different Ecological Wetland Beds

作　　者：侯霜[1] 李子富[1,2] 张扬[1] 

机构地区：[1]北京科技大学土木与环境工程学院环境工程专业,北京100083 [2]北京市工业典型污染物资源化处理重点实验室,北京100083

出　　处：《环境科学研究》2015年第4期589-595,共7页Research of Environmental Sciences

基　　金：中央高校基本科研业务费专项资金(FRF-1C-11-001);昆明市科技计划项目(2012-01-10-A-G-01-0001)

摘　　要：对比分析传统干化床、芦苇生态床及芦苇-蚯蚓复合生态床3种处理方式对城镇污水处理厂剩余污泥的处理效果.结果表明:传统干化床处理简单易行、成本低,但脱水效率低,处理15 d后污泥含水率仍在79.8%左右.芦苇生态床较传统干化床具有明显优势,其处置后污泥含水率可降至67.8%,但其对有机质、TN、TP的去除效果不明显.芦苇-蚯蚓复合生态床对污泥脱水效果最佳:1污泥含水率由原来的95.1%降至44.4%,体积明显减少,达到了污泥减量化的目标;2扫描电镜试验显示,处理后污泥具有孔隙及片状结构,有利于水分散失;3污泥中w(有机质)、w(TN)、w(TP)分别降低了14.5%、20.3%和13.2%左右.热重分析发现,污泥中不稳定化合物含量有所降低.经芦苇-蚯蚓复合生态床处理后,Cu、Ni、Zn、Cr残渣态所占比例分别由原污泥的3.2%、23.7%、15.2%、55.8%增至73.3%、43.1%、78.3%和78.6%,大幅降低了重金属的迁移风险,并且污泥红外图谱显示─COOH和酰胺明显增多,有利于重金属的稳定.综上,复合生态床可有效实现污泥减量,并且降低了二次污染的风险.The effects of sludge ecological treatment were investigated, and the treatment efficiencies of the traditional drying bed, reed bed and reed and earthworm integrated wetland system were compared. The results showed that the traditional drying bed was easy to operate and relatively inexpensive, but its sludge dewatering efficiency was low. The moisture content of sludge was 79.8% after 15 days. The reed bed was superior to the traditional drying bed. The moisture content of the sludge in the reed bed decreased to 67.8% , but the removal rates of organic matter, total nitrogen and phosphorus were insignificant. The reed and earthworm integrated wetland system had obvious effects on sludge dewatering. The moisture content of sludge decreased from 95.1% to 44.4%, and the volume apparently decreased. Electron microscopy demonstrated that the sludge treated by the integrated wetland system had interspaces and lamellar structures, benefitting air and moisture loss. Thus, the reduction targets were achieved. The organic matter, total nitrogen and phosphorus were reduced by 14.5% , 20.3% and 13.2% , respectively. Thermo gravimetric analysis showed that the volatile compound content in the sludge bed decreased. The residue ratios of Cu, Ni, Zn and Cr in the sludge increased from 3.2% , 23.7% , 15.2% and 55.8% to 73.3% , 43.1% , 78.3% and 78.6% , respectively; thus the heavy metal contents in sludge were stabilized. Infrared spectroscopy showed that the sludge treated by the integrated wetland system had more -COOH and amide, which catalyzed the stabilization of heavy metals. Therefore, the reed and earthworm integrated wetland system effectively enhanced sludge stabilization and reduced secondary

关 键 词：芦苇-蚯蚓复合生态床 污泥脱水 污泥稳定化 

分 类 号：X705[环境科学与工程—环境工程]