| چکیده انگلیسی مقاله |
Background and Objective: Sewage sludge, a byproduct of wastewater treatment plants, is rich in organic matter and nutrients. With appropriate treatment, sludge can be utilized as a fertilizer for agriculture and soil amendment. This study aimed to evaluate the microbial quality of wastewater treatment plants in Tehran.
Materials and Methods: This study was conducted during the winter of 2018. A total of 25 samples were collected from the dewatering tank and sludge storage areas. Fecal coliform counts were determined using EPA Method 1681, while Salmonella and parasite egg counts were assessed using EPA Methods 1682 and 1992, respectively.
Results: In the dewatered sludge, fecal coliform levels ranged from a minimum of 67 MPN/g.TS on the first day to a maximum of 18,518 MPN/g.TS on the third day. Salmonella levels measured on the fifth, eighth, and tenth days were 0.55, 0.32, and 0.66 MPN/4g.TS, respectively. Parasite egg counts recorded on the second, ninth, and tenth days were 4 OVA/4g.TS. In the stored sludge, regardless of depth or geographic location of the disposal land, fecal coliform counts during retention times of 2, 3, 4, 5, 6, 7, 8, and 9 years were 10, 186, 480, 30, 27, 29032, 2, and 11 MPN/g.TS, respectively. Salmonella and parasite eggs were not detected in the stored sludge.
Conclusion: The findings indicate that, in the sludge storage unit compared to the sludge dewatering unit, achieving Class A standards for sludge is feasible through continuous quality monitoring.
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| نویسندگان مقاله |
مریم غنی | Maryam Ghani
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی تهران، تهران، ایران
معصومه عسکری | Masoomeh Askari
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی تهران، تهران، ایران
بابک محمودی | Babak Mahmoudi
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی تهران، تهران، ایران
نجات موسوی پور | Nejat Mousavipour
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی تهران، تهران، ایران
رضا براتی رشوانلو | Reza Barati Rashvanlou
Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran AND Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
مرکز تحقیقات فناوری بهداشت محیط، دانشگاه علوم پزشکی ایران، تهران، ایران و گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی ایران، تهران، ایران
شاهرخ نظم آرا | Shahrokh Nazmara
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Solid Waste Research (CSWR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran
گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی تهران، تهران، ایران و مرکز تحقیقات مواد زائد جامد، پژوهشکده محیط زیست، دانشگاه علوم پزشکی تهران، تهران، ایران
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