Elsevier

Pedosphere

Volume 16, Issue 6, December 2006, Pages 756-761
Pedosphere

Extractable Fractions of Metals in Sewage Sludges from Five Typical Urban Wastewater Treatment Plants of China1

https://doi.org/10.1016/S1002-0160(06)60111-2Get rights and content

ABSTRACT

Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR (Community Bureau of Reference) sequential extraction procedure. The sludges contained considerable amounts of organic matter (31.8%-48.0%), total N (16.3–26.4 g kg−1) and total P (15.1–23.9 g kg−1), indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China's control standards for pollutants in sludges from agricultural use (GB 4284–1984). The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples reflected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.

References (24)

  • S. Bao et al.

    Soil and Agricultural Chemistry Analysis

    (2000)
  • S. Dudka et al.

    Accumulation of potentially toxic elements in plants and their transfer to human food chain

    J. Environ. Sci. Health

    (1999)
  • Cited by (13)

    • Chapter 4 Inorganic and Organic Constituents and Contaminants of Biosolids. Implications for Land Application

      2009, Advances in Agronomy
      Citation Excerpt :

      The amounts present in fractions (i) and (ii) are considered “available” and those in (iii) and (iv) “unavailable.” This method has been extensively used for characterization of biosolids (Alonso et al., 2006, 2009; Alvarez et al., 2002; Fuentes et al., 2004, 2008; Perez-Cid et al., 1999; Scancar et al., 2000; Solis et al., 2002; Sprynskyy et al., 2007; Wang et al., 2005, 2006a,b). To generalize from the results of these studies, Cu is typically found to be concentrated (about 80% of total Cu content) in the oxidizable fraction bound to organic matter.

    • The Effect of Liming and Sewage Sludge Application on Heavy Metal Speciation in Soil

      2017, Bulletin of Environmental Contamination and Toxicology
    View all citing articles on Scopus
    1

    Project supported by the National Key Basic Research Support Foundation of China (No. 2002CB412303) and the Natural Science Foundation of Jiangsu Province (No. KB2004115).

    View full text