Evaluation of Potentially Harmful Substances in Dried Sludge of Isfahan Wastewater Treatment Plants

Document Type : Research Paper

Authors

1 Assoc.Prof. School of Public Health, Isfahan University

2 Assist.Prof. School of Public Health, Isfahan University

3 M.Sc. School of Public Health, Isfahan University

Abstract

Wastewater sludge is categorized as hazardous waste material which must be stabilized and treated before disposal and reuse. Final disposal of sludge from treatment facilities usually involves some form of land disposal. However, sludge contains different type of pathogens and heavy metals which can causes pollution of surface and ground waters, soils and spread diseases if there is human exposure to the sludge. In this respect, U.S.EPA presented requirements for using and disposing of sludge.
Thus, taking into account the potential risks caused by presence of heavy metals in sludge and for the control of processes of sludge treatment and disposal and also protect of environmental health and enhauncement of public health level, specially for farmers and consumers of raw crops, needs sampling and characterization of sludge. In the present research concentration of 11 heavy metals and potentially toxic elements in dried sludge of Isfahan South and North and Shahinshahr wastewater treatment plants were determined using standard methods. Samples have been taken from dried sludge of treatment plants, and been measured after being prepared through atomic absorption apparatus and were compared with EPA enacted standards in regulation 40 CFR part 503. As well, fertilizer value parameters of sludge were measured and were compared with standards and guidelines. The results showed that the average concentration of above elements in all three treatment plants, not exceeded from EPA standards, however, regarding the accumulative property of these elements and lack of necessary protective effects of EPA standards, in using these sludges in the agricultural soils, the necessary caution and care should be taken, in other uses of sludges, however, there is no limitation.

References

1- اسدی، س.ر.، (1374)."بررسی شاخص‌های مهندسی بهداشتی کاربرد پساب و لجن حاصل از تصفیه فاضلاب خانگی در مصارف کشاورزی"، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات.
2- ترکیان، ا.، (1372)."راهنمای آزمایش‌های آب و فاضلاب"، انتشارات دانشگاه علوم پزشکی اصفهان.
3- زرین‌کفش، م.، (1367). "خاکشناسی کاربردی"، انتشارات دانشگاه تهران.
4- گودینی. ح.، (1373). "بررسی اثرات هوادهی، کمپوست کردن، رطوبت و زمان بر روند تثبیت و کیفیت کمپوست زباله‌های شهری"، دانشگاه علوم پزشکی اصفهان.
5- معقول. ن.، (1373). "بررسی مشکلات هضم بی‌هوازی لجن در تصفیه‌خانه فاضلاب شهری اصفهان"، دانشگاه آزاد اسلامی واحد تحصیلات تکمیلی و تحقیقات عالی.
6- منزوی. م.، (1366). "فاضلاب شهری، تصفیه فاضلاب"، چاپ دوم، مؤسسه انتشارات و چاپ دانشگاه تهران.
7- مؤسسه تحقیقات کشاورزی و منابع طبیعی، (1366). "شرح روش‌های تجزیه شیمیایی خاک"، نشریه شماره 893.
8- Hong, R., T., (1993). "The Practical Handbook of Compost Engineering", Lews.
9- Lannelli, M., (1971). "Sludge Treatment and Disposal", Water Services Journal.
10- Lenores, C., (1977). "Standard Method for the Examination of Water and Wastewater", AWWA. A.A.P.HA, AWWA.
11- Metcalf and Eddy, (1991). "Wastewater Engineering Treatment, Disposal, Reuse", McGraw-Hill Book Co., Newyork.
12- Pescod, M.B., (1992). "Wastewater Treatment and Use in Agriculture", F.A.O. of the United Nations, Rome.
13- Carbitts, R., (1989). "Standard Handbook of Environmental Engineering", McGraw-Hill Publishing Co.
14- U.S. EPA, (1992). "Environmental Regulations Technology : Control of Patogens and Vector Attrition in Sewage Sludge", EPA/G25/R-92/03.
15- U.S.EPA., (1983). "Process Design Manual for Land Application of Municipal Sludge", EPA-625/1-83-0/6.
16- U.S.EPA, (1979). "Process Design Manual for Sludge Treatment and Disposal", EPA 625/1-79-Oll.
17- U.S.EPA, (1977). "Process Design Manual Wastewater Treatment Facilities for Sewere Small Communities".
18- U.S.EPA, (1977). "Process Design Manual for Land Treatment of Municipal Wastewater".
19- U.S.EPA, (1974). "Process Design Manual for Sludge Treatment and Disposal".
Journal of Water and Wastewater; Ab va Fazilab ( in persian )
Volume 15, Issue 1 - Serial Number 1
Serial number: 49
May and June 2004
Pages 34-42

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