Krüger Oliver, Adam Christian
BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
Waste Manag. 2015 Nov;45:400-6. doi: 10.1016/j.wasman.2015.01.025. Epub 2015 Feb 16.
Incineration of sewage sludge is expected to increase in the future due to growing concerns about the direct use of sludge in agriculture. Sewage sludge is the pollutant sink of wastewater treatment and thus loaded with contaminants that might pose environmental hazards. Incineration degrades organic pollutants efficiently, but since the ash is currently mostly disposed of, all valuable component like phosphorus (P) and technologically relevant metals present in the sewage sludge ash (SSA) are removed from the economic cycle entirely. We conducted a complete survey of SSA from German mono-incineration facilities and determined the theoretical recovery potential of 57 elements. German SSA contains up to 19,000 t/a P which equals approximately 13% of phosphorus applied in the German agriculture in form of phosphate rock based mineral fertilizers. Thus, SSA is an important secondary resource of P. However, its P-solubility in ammonium citrate solution, an indicator for the bioavailability, is only about 26%. Treatment of SSA is recommended to enhance P bioavailability and remove heavy metals before it is applied as fertilizer. The recovery potential for technologically relevant metals is generally low, but some of these elements might be recovered efficiently in the course of P recovery exploiting synergies.
由于人们对污泥在农业中的直接使用日益担忧，预计未来污水污泥焚烧量将会增加。污水污泥是污水处理的污染物汇集处，因此含有可能造成环境危害的污染物。焚烧能有效降解有机污染物，但由于目前大部分灰分都被处理掉了，污水污泥灰（SSA）中所有有价值的成分，如磷（P）和与技术相关的金属，都完全脱离了经济循环。我们对德国单焚烧设施产生的污水污泥灰进行了全面调查，并确定了57种元素的理论回收潜力。德国的污水污泥灰每年含有多达19000吨的磷，约占德国农业以磷矿石为基础的矿物肥料形式施用的磷的13%。因此，污水污泥灰是一种重要的磷二次资源。然而，其在柠檬酸铵溶液中的磷溶解度（生物有效性的一个指标）仅约为26%。建议在将污水污泥灰用作肥料之前对其进行处理，以提高磷的生物有效性并去除重金属。与技术相关的金属的回收潜力一般较低，但其中一些元素可能在磷回收过程中通过利用协同作用而被高效回收。
