Wetsus, Centre of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911MA Leeuwarden, The Netherlands; Sub-department Environmental Technology, Wageningen University, P.O. Box 17, 6700AA Wageningen, The Netherlands.
Wetsus, Centre of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911MA Leeuwarden, The Netherlands.
J Hazard Mater. 2014 Jun 15;274:229-36. doi: 10.1016/j.jhazmat.2014.04.018. Epub 2014 Apr 23.
Heavy metal content of sewage sludge is currently the most significant factor limiting its reuse in agriculture within the European Union. In the Netherlands most of the produced sewage sludge is incinerated, mineralizing the organic carbon into the atmosphere rather than returning it back to the soil. Source-separation of black water (toilet water) excludes external heavy metal inputs, such as industrial effluents and surface run-offs, producing sludge with reduced heavy metal content that is a more favorable source for resource recovery. The results presented in this paper show that feces is the main contributor to the heavy metal loading of vacuum collected black water (52-84%), while in sewage the contribution of feces is less than 10%. To distinguish black water from sewage in the sludge reuse regulation, a control parameter should be implemented, such as the Hg and Pb content that is significantly higher in sewage sludge compared to black water sludge (from 50- to 200-fold). The heavy metals in feces and urine are primarily from dietary sources, and promotion of the soil application of black water sludge over livestock manure and artificial fertilizers could further reduce the heavy metal content in the soil/food cycle.
污水污泥中的重金属含量目前是限制其在欧盟农业中再利用的最主要因素。在荷兰，大部分产生的污水污泥都被焚烧，将有机碳矿化到大气中，而不是将其返回土壤。黑水（厕所水）的源头分离排除了外部重金属的输入，如工业废水和地表径流，产生的污泥重金属含量较低，是资源回收的更有利来源。本文的研究结果表明，粪便对真空收集的黑水（52-84%）中的重金属负荷的贡献最大，而在污水中，粪便的贡献小于 10%。为了在污泥再利用法规中将黑水与污水区分开来，应该实施一个控制参数，如汞（Hg）和铅（Pb）的含量，与污水污泥相比，其在黑水污泥中的含量要高得多（50 到 200 倍）。粪便和尿液中的重金属主要来自饮食来源，推广将黑水污泥施用于土壤，而不是牲畜粪便和人工肥料，可以进一步降低土壤/食物链中的重金属含量。
