Sludge Characterization of an Industrial Wastewater Treatment Plant, Iran

Background and purpose: Disposing sludge from industrial wastewater treatment plants (IWWTPs) is a serious issue because it can affect human and animals health, and also environmental quality. In this study, sludge from an IWWTP was analyzed regarding its physicochemical characteristics and disposal options. Materials and Methods: Grab sampling was used to collect 12 sludge samples biweekly (May-October 2012). One sample T-test was applied to analyze the obtained data. Canadian Soil Quality Guidelines (CSQG) and New Jersey Department of Environmental Protection Soil Cleanup Criteria (NJDEPSCC) were used to discuss the generated sludge disposal fate. Results: The results show that the order of the studied metals in the sludge was as: Fe>Al>Zn>Cr>Pb>Ni>Cd>Co>Cu>Mn>As>Hg. It was found that the generated sludge compared with CSQG is not suitable for residential/parkland, agricultural, commercial and industrial applications. But compared with NJDEPSCC, the studied sludge was suitable for residential and non-residential applications. Conclusion: According to NJDEPSCC, the studied sludge has the potential to be used for residential and non-residential purposes.