Digestion Procedure and Determination of Heavy Metals in Sewage Sludge—An Analytical Problem
Digestion Procedure and Determination of Heavy Metals in Sewage Sludge—An Analytical Problem
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污泥中重金属的消化过程和测定——一个分析问题
DOI：
10.3390/su11061753
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发表时间：
2019
期刊：
影响因子：
3.9
通讯作者：
W. Wolf
中科院分区：
文献类型：
--
作者：
A. Turek;K. Wieczorek;W. Wolf
全球产生的大量污水污泥对环境构成严重威胁，需要合理处理。在农业上的应用是一种经济和相对简单的污泥管理方法，但它与金属含量的限制有关。根据欧盟的规定，镉、铜、铬、铅、镍和锌的总量必须用原子吸收光谱分析技术进行分析，这需要有效地破坏有机基质。目前使用的污泥消化方法，如果没有经过优化应用，可能会出现偏差。本工作的目的是评价生泥和稳定化污泥中有机物的破坏效率。评估了三种矿化程序，即：(A)干燥和微波消解；(B)点火和微波消解；(C)干燥和常规消解。对于基质的破坏，使用浓硝酸和HCl(3：1v/v)的混合物。用火焰原子吸收光谱法(FAAS)测定金属。没有透支金属浓度的限制。总的来说，方法(B)是最有效的。方法(A)和(B)消化后铜、镉和锌的测定结果具有可比性。方法(B)和(C)产生基质的完全分解。结果，测量精度大大提高。
Huge amounts of sewage sludge produced globally is a substantial environmental threat and require rational handling. Application in agriculture is an economical and relatively simple method of sludge management, however, it is associated with restrictions regarding metals content. According to EU regulations, the total amounts of Cd, Cu, Cr, Pb, Ni, and Zn have to be analyzed by the AAS technique requiring effective destruction of the organic matrix. Currently used methods of sewage sludge digestion may be biased when applied without optimization. The aim of the presented work was to evaluate the efficiency of the organic substances destruction in either raw or stabilized sludge. Three mineralization procedures were evaluated, namely: (A)—drying and microwave digestion; (B)—ignition and microwave digestion; (C)—drying and conventional digestion. For matrix destruction, a mixture of concentrated HNO3 and HCl (3:1 v/v) was used. Metals were determined by flame atomic absorption spectrometry (FAAS). No limits of metal concentration were overdrawn. Generally, the method (B) was the most effective. Results obtained for Cu, Cd, and Zn after digestion by method (A) and (B) were comparable. Methods (B) and (C) yield complete decomposition of the matrix. As result, the precision of measurement substantially increases.