نوع مقاله : مقاله پژوهشی
نویسندگان
1 استادیار /دانشکده مهندسی عمران. دانشگاه صنعتی اصفهان
2 دانشآموخته ارشد مهندسی /عمران مهندسی محیط زیست .دانشگاه خوارزمی تهران
3 دانشگاه آزاد اسلامی/ واحد تهران جنوب، باشگاه پژوهشگران جوان و نخبگان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
According to the rapid population growth and increasing need for clean and reliable water, wastewater treatment plants play an important role in providing a reliable source of water. In this regard, the reliability of a wastewater treatment plant is a critical issue while the effluent is reused or discharged to water resources. Main factors that affect the performance of a wastewater treatment plant are the variability of the influent, inherent variability in the treatment processes, deficiencies in design and mechanical equipments and operational failures. Thus, meeting established reuse and discharge criteria would require assessment of plant reliability. Amongst many techniques developed in system reliability analysis, Fault Tree Analysis (FTA) is one of the popular and efficient methods. FTA is a top down, deductive failure analysis in which an undesired state of a system, including failure to achieve system goals, is analyzed. The case study in this article is West Town wastewater treatment plant in Tehran which is a conventional activated sludge process and the effluent is used in irrigation of downstream green areas. The FTA components in this study include the violation of BOD from the standard limit for irrigation as the top event and cases such as operator fault, malfunction of the equipments and failure in the plant design as the basic events. The probabilities of basic events were determined based on available data and the experts’ and operators’ opinions and the probability of the top event was calculated. According to the obtained results, the probability of effluent BOD violation is estimated about 29% in which human error specially operator’s fault has the highest share in its occurance. Subsequently the mechanical, climate (influent wastewater quantity and quality) and factors related to collection network are placed in the following order. In this regard, to increase the reliability and management of the risk, some measures with the priority of focusing on reduction of human faults and incresing the level of supervision and inspection was recommended
کلیدواژهها [English]