CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
J Environ Manage. 2019 Nov 1;249:109427. doi: 10.1016/j.jenvman.2019.109427. Epub 2019 Aug 24.
Industrialization and accelerated population growth have created a huge amount of sewage sludge. Many studies have reported the sewage sludge as a sink of major and trace elements, but less is known about their geochemical fractionations. In order to assess the mobility, the distribution, bioavailability, and toxicity of those elements in sludge, we collected the sewage sludge samples from all the seven wastewater treatment plants in Xiamen City, China. Results revealed a strong spatial variation and the occurrence of 48 elements with concentrations ranging from 1.00×10 mg kg (Re) to 9.03×10 g kg (Fe) on the basis of dry sludge weight. Sequential extraction procedure showed that residual and oxidizable fractions were the main geochemical fractions of most studied elements. However, Ca, Mn, Sr, and Ni were mainly bound to acid-exchangeable fractions, while Fe, Zn, Cd, Cr, Co, and V were mainly distributed in the reducible fractions. The contamination factor and risk assessment code indicated that Ni, Cu, Zn, Cd, Cr, Co, Sr, Ca, Mn, Mo, Re, and W were highly mobile with less retention time and exerted high environmental risks through sludge land application. The sludge disposal strategy should consider not only the total concentrations of a broad range of elements but also their bioavailability.
工业化和人口的快速增长产生了大量的污水污泥。许多研究报告指出，污水污泥是主要和微量元素的汇，但对于它们的地球化学分馏知之甚少。为了评估污泥中这些元素的迁移性、分布、生物可利用性和毒性，我们采集了中国厦门市所有 7 个污水处理厂的污水污泥样品。结果表明，基于干污泥重量，存在很强的空间变异性，并且有 48 种元素的浓度范围从 1.00×10 mg kg（Re）到 9.03×10 g kg（Fe）。连续提取程序表明，残渣和可氧化部分是大多数研究元素的主要地球化学部分。然而，Ca、Mn、Sr 和 Ni 主要与可交换酸部分结合，而 Fe、Zn、Cd、Cr、Co 和 V 主要分布在可还原部分。污染因子和风险评估代码表明，Ni、Cu、Zn、Cd、Cr、Co、Sr、Ca、Mn、Mo、Re 和 W 具有较高的迁移性，保留时间较短，通过污泥土地应用对环境造成高风险。污泥处置策略不仅应考虑各种元素的总浓度，还应考虑其生物可利用性。
