Ecology, Environment and Conservation Paper

A SURVEY ON NUTRIENT REMOVAL IN A COMBINED WASTEWATER TREATMENT SYSTEM IN KASHAN UNIVERSITY OF MEDICAL SCIENCE, IRAN

Gholamreza Hoseindoost, Mohammad Bagher Miranzadeh, Milad Ahmadi, Vahid Hallajian, Hamid Reza Shokuhi Borj and Hosein Siaf

Abstract

Recently attention to nutrient removal in the wastewater treatment systems has increased since the entry of nutrients into the environment can cause water resources pollution and other health hazards. The purpose of this study is to investigate the efficiency of sewage infiltration system of Kashan Medical Science University in the year 90-91. This study was conducted as a descriptive-periodic study in order to investigate the efficiency of the wastewater treatment system of the Central Campus of Kashan University of Medical Science in the years 2010-2011. The samples were taken in the two seasons of winter and summer and from three zones of the wastewater treatment plant (influent wastewater, wastewater activated sludge process and wastewater maturation pond) in 12 stages of sampling and were carried out on the analysis of ammonia- N, organic nitrogen, nitrate, total nitrogen and total phosphorus. The data obtained from the study showed that removal the total efficiency of organic nitrogen, total nitrogen and total phosphorus removal in the two seasons of winter and summer had a significant difference with each other, but regarding ammonia, there was no significant difference in the percentage of removal in the two seasons above (pv>0.05). Furthermore, in the system above the efficiency of nutrient materials removal in the activated sludge process and extended aeration process was more than maturation pond which is due to the higher removal of pathogens in comparison with the nutrient removal in the maturation ponds. Regarding phosphorus, percentage of removal in the activated sludge process in summer was more than that of winter; but in the maturation pond the opposite of this has taken place which is due to more dissolution of phosphorus from the pond floor sludge and its re-entry into the wastewater in the warm seasons of the year. Based on the results obtained from this study, it could be concluded that climactic conditions have more effects on the efficiency of nutrient removal in stabilization ponds compared with the activated sludge process.