Investigation of sewage sludge quality for land application: A case study: Two Isfahan wastewater treatment plans

Document Type : Original Article

Authors
Hamid Reza Rahmani 1
Hamed Rezaei 1
Mohammad Mehdi Amin 2
Zohreh Mazaheri Kohanestani 3
1 Soil and Water Institute of Iran, Isfahan, Iran
2 Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
3 Department of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
10.4103/2277-9183.170703
Abstract
Aims: The aim of this study was to investigate sewage sludge quality of Isfahan wastewater treatment plants (WWTPs) as a fertilizer in agricultural lands. Materials and Methods: The samples were collected seasonally from two WWTPs, including North-Isfahan and Shahin-Shahr in 2012 and 2013, seasonally and biochemical parameters were measured for each site. Results: The studied parameters were meet the Iranian standard level, including pH, nitrogen, phosphorous, potassium, calcium, total solids, organic matter, and moisture content except of magnesium. The carbon-nitrogen ratios was varied 7.41-9.45 and 8.7-9 in Shahin-Shahr and North-Isfahan WWTPs, respectively. The organic nitrogen was composed the highest percentage of the total nitrogen (about 78%) and inorganic nitrogen was in normal ranges. The electrical conductivity was varied 5-8.8 ds/m to 4.6-7.5 ds/m in Shahin-Shahr and North-Isfahan WWTPs, respectively. It may contribute to soil salinity in long term. Maximum nitrogen and phosphorous values were related to winter samples in both WWTPs. In Shahin-Shahr WWTP, minimum and maximum of potassium, calcium, and magnesium were measured in spring while they were the highest in spring in North-Isfahan WWTP. Conclusion: Application of sewage sludge of Isfahan WWTP as a fertilizer could be useful regardless to its microbial contents because it provides essential nutrients for plants growth regardless to its fecal and total coliforms.

Keywords

International Journal of Environmental Health Engineering (IJEHE)
Volume 4, November
Autumn 2015
Pages 1-6

  • Receive Date 27 January 2023