Venkatesan Arjun K, Halden Rolf U
Center for Environmental Security, The Biodesign Institute, Global Security Initiative, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287, United States.
Center for Environmental Security, The Biodesign Institute, Global Security Initiative, Arizona State University, 781 E. Terrace Mall, Tempe, AZ 85287, United States.
Sci Total Environ. 2016 Apr 15;550:736-741. doi: 10.1016/j.scitotenv.2016.01.119. Epub 2016 Feb 2.
A model was developed to assess the impact of adding acids and bases to processed municipal sewage sludge (MSS) to mobilize contaminants, facilitating their removal from sludge by flushing prior to land application. Among 312 organic contaminants documented to occur in U.S. MSS, 71 or 23% were identified as ionizable organic contaminants (IOCs), contributing a disproportionately large fraction of 82% of the total mass of sludge-borne contaminants. Detected IOCs included 57 pharmaceuticals and personal care products, 12 perfluorinated compounds, one surfactant and one pesticide. Annually, about 2000t of IOCs were estimated to be released to U.S. soils via land-application of MSS. A partitioning model developed to assess the impact of pH on hydrophobic sorption revealed that between 36 and 85% of the mass of individual classes of IOCs potentially could be desorbed from MSS via pH adjustment and flushing. Thus, modeling results suggest that a sequential pH treatment [acidic (pH2) followed by basic (pH12) treatment] has the potential to reduce the burden of harmful IOCs in MSS applied on U.S. land by up to 40±16t annually. This approach may serve as a cost-effective treatment process that can be implemented easily in existing sludge treatment infrastructure in the U.S. and worldwide, serving to significantly improve the quality of MSS destined for land application.
开发了一种模型，以评估向处理后的城市污水污泥（MSS）中添加酸和碱以 mobilize 污染物的影响，从而便于在土地施用前通过冲洗将其从污泥中去除。在美国记录的 312 种存在于 MSS 中的有机污染物中，有 71 种或 23%被确定为可电离有机污染物（IOC），它们在污泥携带污染物总质量中所占比例高达 82%，占比极不相称。检测到的 IOC 包括 57 种药品和个人护理产品、12 种全氟化合物、1 种表面活性剂和 1 种农药。据估计，每年通过土地施用 MSS 有大约 2000 吨 IOC 释放到美国土壤中。为评估 pH 对疏水吸附的影响而开发的分配模型表明，通过调节 pH 和冲洗，单个类别的 IOC 中 36%至 85%的质量可能会从 MSS 中解吸出来。因此，模型结果表明，顺序 pH 处理（先酸性（pH2）后碱性（pH12）处理）有可能使每年施用于美国土地的 MSS 中有害 IOC 的负担减少多达 40±16 吨。这种方法可能是一种具有成本效益的处理工艺，可以在美国和全球现有的污泥处理基础设施中轻松实施，有助于显著提高用于土地施用的 MSS 的质量。
