Investigation of the Efficiency of Sewage Treatment using Activated Sludge Method to Supply Water for Reuse in Agricultural Irrigation (Case Study: Kermanshah Sewage Treatment Plant)

Considering the environmental regulations on exhausting sewage from treatment plants and its application in agriculture, this research investigates the use of activated sewage efficiency in the generative sewage treatment of Kermanshah city and its application on agriculture irrigation through 2007 to 2008 using the cross-sectional method. During the course of this study, sampling was carried out from the inlet and outlet of the sewage treatment plant on a daily and weekly basis. Treatment plant efficiency was calculated through the measurements of TSS, COD, BOD5, MLVSS, SVI, and MLSS from the entrance sewage and exhausting effluent based on the latest standard methods presented in 1999. Also, indices relevant to the agricultural usability were calculated and compared with the national standards. Results showed that physical, chemical, and biological traits of sewage pollution intensity were at an average level and the treatment plant pollution efficiency was relatively acceptable. The average concentration of dissolved oxygen (mg/l), SVI, MLSS, and MLVSS in the aerated pool was compared with the environment protection standards of Iran showed that the exhausting effluent can be used in drip irrigation. Despite the appropriate control of the active-sludge process in all parts of a sewage treatment plant, results showed a lack of adequate management on its sustainable consumption such as its application in the production of agricultural fertilizers.