Bir Evsel Atıksu Arıtma Tesisinde İşletme Maliyetlerinin İncelenmesi

Abstract

Amaç: Son yıllarda gelişen teknoloji ve ekonomi koşulları sayesinde kentsel atıksu arıtma tesisi AAT inşaatları hızlanmıştır. Atıksu arıtma tesislerinin planlanmasında genellikle atıksu özellikleri ve arıtma gereksinimleri dikkate alınmaktadır. Ancak, arıtma tesisinin sürdürülebilirliği için en az yatırım maliyeti kadar işletme maliyetleri de önem arz etmektedir. Arıtma ünitelerinde işletme sırasında kullanılan ekipmanın performansı ve atık su arıtma tesislerinin başarısı ve sürdürülebilirliği için atık su özellikleri oldukça önemlidir. Bu çalışmada, 108.000 nüfuslu yerleşim için tasarlamış ileri bir biyolojik arıtma olarak tasarlanan kentsel atıksu arıtma tesisinin işletme maliyetlerinin ayrıntılı incelenmesi ve gerçek işletme verilerinin belirlenmesi amaçlanmıştır.Yöntem: Söz konusu arıtma tesisinin işletme maliyet analizinde elektrik tüketimi, kullanılan kimyasal ajan, personel sayısı, bakım-onarım ve tesisin her birimindeki diğer giderler dikkate alınmıştır. İlk olarak, her arıtma ünitesinin bireysel işletme maliyetleri çalışma koşullarına ve ekipman özelliklerine göre hesaplanmıştır. Ardından toplam işletme maliyetleri günlük, aylık ve yıllık olarak belirlenmiştir. Then, total operating costs were determined daily, monthly and yearly. According to determined operating costs, treatment costs both per volume and pollution load of wastewater were calculated. Lastly, these data were compared with the previous studies.Results: The total operating costs of the plant have been calculated as about 592 740 $/year. The electricity requirement is 42% of the total operating costs. The highest operating cost in the plant is at the activated sludge unit and calculated as 223 437 $/year. It is determined that total energy requirements are 0.88 kWh, 58.75 kWh and 2.22 kWh for per m3 wastewater, per person, and per kg COD Chemical Oxygen Demand , respectively.Conclusion: The operating costs and total costs calculated in this study are compatible with the costs obtained from previous studies. Generally, it may be said that operating costs in the WWTP are most affected by electricity and staff expenses. Since this study was conducted on a medium-sized WWTP, the energy costs of the equipment in the activated sludge unit have a higher percentage than other expenses

Keywords

• İşletme maliyetleri, kentsel atıksu arıtma tesisi, atıksu arıtma tesisleri için enerji ihtiyacı

Investigation of Operating Costs at an Urban Wastewater Treatment Plant

Abstract

Objective: In recent years, thanks to improving technology and economic conditions urban wastewater treatment plant WWTP constructions have accelerated. Wastewater characteristics and treatment requirements usually are taken into account for the planning of wastewater treatment plants. But, operation costs also are important as the least investment costs for the sustainability of the treatment plant. The performance of equipment used in the treatment units during the operation is important as well as the wastewater characteristics for the accomplishment and sustainability of wastewater treatment plants designed. In this study, it has been aimed investigation as detailed of operation costs of an urban wastewater treatment plant that is designed as an advanced biological treatment for a settlement of 108.000 populations, and determination of real operation data.Methods: Electricity consumption, the chemical agent used, staff number, maintenance-repair, and other expenses at each unit of the plant have been considered at the operation cost analysis of the aforementioned plant. Firstly, the individual operating costs of each treatment unit were calculated according to its running conditions and equipment properties. Then, total operating costs were determined daily, monthly and yearly. According to determined operating costs, treatment costs both per volume and pollution load of wastewater were calculated. Lastly, these data were compared with the previous studies.Results: The total operating costs of the plant have been calculated as about 592 740 $/year. The electricity requirement is 42% of the total operating costs. The highest operating cost in the plant is at the activated sludge unit and calculated as 223 437 $/year. It is determined that total energy requirements are 0.88 kWh, 58.75 kWh and 2.22 kWh for per m3 wastewater, per person, and per kg COD Chemical Oxygen Demand , respectively.Conclusion: The operating costs and total costs calculated in this study are compatible with the costs obtained from previous studies. Generally, it may be said that operating costs in the WWTP are most affected by electricity and staff expenses. Since this study was conducted on a medium-sized WWTP, the energy costs of the equipment in the activated sludge unit have a higher percentage than other expenses

Keywords

• Operating costs, urban wastewater treatment plant, energy requirement for WWTPs

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