Document Type : Research article
Authors
1 Department of Natural Resources Isfahan University of Technology
2 MSc of Environmental pollution, Department of natural resources, Isfahan university of technology
Abstract
Background and Objectives: Today, sewage sludge disposal methods include drying, burning and application in land, but each of these methods has its own vulnerability. Sewage sludge management is difficult not only because of high levels of production, but also because of high concentrations of heavy metals and pathogens. Research has shown that the transfer of sewage sludge to organic fertilizers, including organic fertilizer, is due to its many advantages, including less heavy metals, easy to use with irrigation systems, faster absorption by plants, and increased their growth efficiency etc. which have been very much considered. The purpose of this study was to investigate the properties of sewage sludge and the liquid fertilizer produced from it.
Materials and Methods: In this study, biological sludge was transformed into liquid fertilizer using a 0.25 molar solution. Characterization of biological sludge and liquid fertilizer by conducting heavy metal concentration tests (Zn, Pb, Cd, Cr, Ni, Fe and Cu), total nitrogen, total phosphorus, soluble potassium, total sodium concentration, electrical conductivity and pH was done.
Results: The results showed that total nitrogen, soluble potassium, heavy metals concentration decreased with increasing of organic matter extraction from sludge whereas, the amount of phosphorus, total sodium content, electrical conductivity and pH increased.
Conclusion: The results of this study showed that the liquid fertilizer produced from sewage sludge due to its characteristics can be used as a soil modifier in agricultural sector.
Keywords
- Song X, Xue X, Chen D, He P, Dai X. Application of biochar from sewage sludge to plant cultivation: Influence of pyrolysis temperature and biochar-to-soil ratio on yield and heavy metal accumulation. Chemosphere. 2014;109:213-20.
- Agrafioti E, Bouras G, Kalderis D, Diamadopoulos E. Biochar production by sewage sludge pyrolysis. Journal of Analytical and Applied Pyrolysis. 2013;101:72-8.
- Norimand k, Nezhad S. Activated sludge process and its strategic foundations. Ameh Tehran. 2000;in Persian.
- Erfanmanesh M, Afuni A. Environmental pollution (water, soil and air). Arkan Danesh. 2014;in Persian.
- Udom BE, Mbagewu JSC, Adesodun Jk, Agbim NN. Distributions of zinc, copper, cadmium and lead in a tropical ultisol after long-term disposal of sewage sludge. Environment International 2004;30(4):467-70.
- Abedi MJ, Najafi P. Use of treated wastewater in agriculture. Iran: National Irrigation and Drainage Committee Of Iran; 2001.
- Low EW, Chase HA. Reducing production of excess biomass during wastewater treatment. Water research. 1999;33(5):1119-32.
- Saeidi H. Production of organic liquid fertilizer from urban sewage sludge and compost [dissertation]. Isfahan University of Technology. 2013;in Persian.
- Nouri j. Environmental Biotechnology. Jafar Nouri 1994.
- Zare M, Charm M, Moallemi N. Effect of Treated Urban Sewage Sludge on Soil Essential Nutrients, Soil Chemical Properties and Physiological Properties of Olive Tree. Journal of Agriculture Engineering. 2014;37(2). in Persian.
- Jambaldorj G, Takahashi M, Yoshikawa K, editors. Liquid fertilizer production from sewage sludge by hydrothermal treatment. Proceedings of International Symposium on EcoTopia Science; 2007.
- Sladký Z. The effect of extracted humus substances on growth of tomato plants. Biologia Plantarum. 1959;1(2):142-50.
- ASTM D, 1971-02. Standard Practices for Digestion of Water Samples for Determination of Metals by Flame Automatic Absorption, Graphite Furnace Atomic Absorption. Plasma Emission Spectroscopy, or Plasma Mass Spectrometry. 2003.
- Klute A. Methods of soil analysis, part I, physical and mineralogical methods. USA: USA: Wisconsin; 1986.
- Rezvanipur H, Dinani ZR. Chemical analysis of water and soil (with environmental and health vision). Iran, Isfahan: Isfahan University of Technology. 2014;in Persian.
- ASTM D, 4980-89. Standard test methods for screening of pH in waste. In: editor.^editors. ed. 1989.
- Li H, Jin Y, Mahar R, Wang Z, Nie Y. Effects and model of alkaline waste activated sludge treatment. Bioresource technology. 2008;99(11):5140-4.
- Lin J-G, Chang C-N, Chang S-C. Enhancement of anaerobic digestion of waste activated sludge by alkaline solubilization. Bioresource technology. 1997;62(3):85-90.
- Rajan R, Lin J-G, Ray BT. Low-level chemical pretreatment for enhanced sludge solubilization. Research Journal of the Water Pollution Control Federation. 1989:1678-83.
- Agency, USE. Background Report on Fertilizer Use, Contaminants and Regulations. Washington. DIANE 2000.
- Zhou C, Wang R, Zhang Y. Fertilizer efficiency and environmental risk of irrigating Impatiens with composting leachate in decentralized solid waste management. Waste Management. 2010;30(6):1000-5.
)