调理剂比例对污泥蚯蚓堆肥的影响

以不同比例的牛粪作为调理剂,利用蚯蚓堆肥处理城市污泥,研究蚯蚓生长状况、产物营养物质(氮、磷、钾、有机质)和重金属(Pb、Cr、Cd、Hg、As)的变化.结果表明,试验结束后各处理蚯蚓条数差异不显著；1∶0(污泥和牛粪干重质量比,下同)处理的蚯蚓总重量和平均单条重量最大；1∶0处理的个体平均增重显著高于1∶1处理；污泥经蚯蚓堆肥后营养成分下降,牛粪营养成分增加；1∶0处理产物全氮含量显著高于1∶2处理；1∶0处理的全磷含量最高；各处理间全钾含量差异不显著.纯牛粪0∶1处理的有机质含量最高；1∶0处理的氮、磷、钾总量显著高于其他处理.污泥堆肥后Pb、Cd、Hg含量下降,而Cr、As的含量升高；牛粪堆肥后各种重金属上升,1∶2、1∶1、2∶1、1∶0处理各种重金属含量均显著高于0∶1处理；1∶2、1∶1、2∶1处理间Pb、Cr、Cd差异不显著；2∶1处理的Hg、As含量与1∶1处理差异不显著,但显著高于1∶2处理.

Effect of Conditioners Ratio on Composting of Sewage Sludge by Earthworm

The change of earthworm biomass,content of nutrients and heavy metals in compost of sewage sludge with earthworms when adding different ratio of cow dung as conditioner were studied.The results showed that the number of earthworms had no significant difference among all treatments.The total weight and average weight of earthworms was the highest when the mass ratio of sewage sludge to cow dung was 1∶0;and the average increasement of individual weight in this treatment was higher than that of 1∶1 treatment.The content of nutrients in sewage sludge decreased,while increased in cow dung when composted by earthworm.The content of total N in the 1∶0 treatment was significantly higher than that in the 1∶2 treatment;and the content of total P in the 1∶0 treatment was the highest;but the content of total K in all treatments had no significant difference.The content of organic matter in the 0∶1 treatment was the highest.The total content of N,P and K in the 1∶0 treatment was higher than that in other treatments.The contents of Pb,Cd,and Hg of sludge decreased after composting with earthworm,while the content of Cr and As increased.The content of each heavy metals of cow dung increased after composting.The content of each heavy metal of compost in 1∶2,1∶1,2∶1,and 1∶0 treatment were significantly higher than that in the 0∶1 treatment.The content of Pb,Cr,Cd of compost among 1∶2,1∶1,2∶1 treatments had no difference.The content of Hg and As between 2∶1 and 1∶1 treatments had no obvious difference,but was significantly higher than that of 1∶2 treatment.