Bilgehan Nas
Selçuk University
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Featured researches published by Bilgehan Nas.
Waste Management | 2010
Sehnaz Sener; Erhan Sener; Bilgehan Nas; Remzi Karagüzel
Landfills are the most common method for the disposal of municipal solid waste (MSW) in Turkey. However, determining the location of landfill sites is a difficult and complex process because it must combine social, environmental and technical parameters. Additionally, it depends on several criteria and regulations. The main objective of this study was to select of a landfill site for the Lake Beyşehir catchment area. The Beyşehir Lake is the largest freshwater lake and drinking water reservoir in Turkey, but there is no controlled landfill site in the region. Therefore, the landfill site should be determined such that the lake is protected. To determine the most suitable landfill site, an analytical hierarchy process (AHP) was combined with a geographic information system (GIS) to examine several criteria, such as geology/hydrogeology, land use, slope, height, aspect and distance from settlements, surface waters, roads, and protected areas (ecologic, scientific or historic). Each criterion was evaluated with the aid of AHP and mapped by GIS. Data were assorted into four suitability classes within the study area, i.e., high, moderate, low and very low suitability areas, which represented 3.24%, 7.55%, 12.70% and 2.81%, of the study area, respectively. Additionally, 73.70% was determined to be completely unsuitable for a landfill site. As a result, two candidate landfill sites are suggested and discussed. The final decision for landfill site selection will require more detailed field studies.
Environmental Monitoring and Assessment | 2010
Bilgehan Nas; Tayfun Cay; Fatih Iscan; Ali Berktay
Landfill is a common solution for the final disposal of municipal solid waste (MSW) in Turkey. Landfill siting is an extremely difficult task to accomplish because the site selection process depends on different factors and regulations. To ensure that an appropriate site is chosen, a systematic process should be developed and followed. Unsuccessful landfill siting is typically the result of strong public opposition. In this study, candidate sites for an appropriate landfill area in Cumra County of Konya City are determined by using the integration of geographic information systems (GIS) and multi-criteria evaluation (MCE). ArcGIS 9.0 software and its extensions were used as the GIS tool since it is able to perform suitability analysis using MCE analysis. To identify appropriate landfill areas in the Cumra district, eight input map layers including proximity to municipal and local wells and irrigational canals, distance from transportation routes and rails, distance from archaeological sites, distance from urban areas, land use/land cover, and land slope are used in constraint mapping. A final map was generated which identifies regions showing suitability for the location of the landfill site. According to the map, 6.8% of the study area is most suitable, 15.7% is suitable, 10.4% is moderately suitable, 25.8% is poorly suitable, and 41.3% is unsuitable. At the end of the analyses, three candidate sites are determined. The selection of the final MSW landfill site, however, requires further field research.
Environmental Technology | 2010
Tuba Yilmaz; Ahmet Aygün; Ali Berktay; Bilgehan Nas
Landfill is a common solution for the final disposal of municipal solid waste in Turkey. In recent years, studies of landfill leachate treatment by Fenton process have indicated that these methods can effectively reduce concentrations of organic contaminants and colour. The aim of this study is to investigate the removal efficiencies of colour and organic matter as COD from young municipal landfill leachate and the effect of operating conditions such as initial pH and Fenton’s reagent dosage. Leachate was collected from municipal sanitary landfill located in city of Konya, Turkey. The main characteristics of the leachate were: pH = 7.25, colour = 3510 ptCo, COD = 38200 mgL−1, BOD5 = 22000 mgL−1, ratio of BOD5/COD was 0.58 and alkalinity as CaCO3 = 10250 mgL−1. It is observed that presenting a high value of COD and BOD5 and the rate of BOD5/COD values indicate that the leachate can be defined as young. The treatment of the leachate by Fenton process was carried out in a batch reactor. Under the optimal operation conditions (initial pH = 3, 2000 mgL−1 Fe2+ and 5000 mgL−1 H2O2), 55.9% of the initial COD and 89.4% colour were removed.
Energy Exploration & Exploitation | 2004
Ali Berktay; Ayhan Demirbas; Saim Koçak; Bilgehan Nas
Electricity is a basic part of nature and it is one of the most widely used forms of energy. Electricity, which is a secondary energy source, can be generated from the conversion of other sources of energy, such as coal, natural gas, oil, nuclear power and renewable resources. Electricity prices have a deep impact on the competitiveness of a countrys industry. Some electricity losses may occur during the process of transmission and distribution from generators to consumers. Generally there are two types of losses, one is technical losses which cover transmission losses and the other is non-technical losses including distribution losses and the incidence of illegal usage. The aim of this paper is to present the electricity usage and prices and is also to focus on the electricity losses occur both technical and non-technical means. An “electricity losses map” was produced to illustrate the electricity losses. For this purpose, a vector-based Geographic Information System (GIS) software package Arc GIS 8.3 was employed to map the data. The rate of losses within the electricity provided to the national network was about 19% in Turkey. The incidence of illegal usage and hence the rate of non-technical losses could be reduced dramatically through establishing regular action.
Energy Exploration & Exploitation | 2006
Ali Berktay; Bilgehan Nas; Ayhan Demirbas
Konya basin is the largest closed basin in Anatolia. Konya plain project (KOP: Konya Ovasi Projeleri in Turkish) is a comprehensive group of projects, which includes construction of dams, hydroelectric power plants, and irrigation systems as well as providing developments in agricultural infrastructure, transportation industry, water supply, water budged, environmental impacts and in other issues. The KOP is described as being the second big project for the purpose of irrigation after South Eastern Project in Turkey. The KOP comprises 47,720 km2 of area spread over four river basins in Konya closed basin. The KOP consists of 12 projects including nine big scale water projects, two water supply projects, energy projects, and a number of small scale surface, and ground water irrigation projects. The KOP area covers the 73% of the total area that can be irrigated in Konya closed basin. Presently, 308,073 ha of land are irrigated by 12 individual projects in the KOP. In order to reach up to 617,923 ha irrigated area, much effort has been done in the all projects.
Desalination and Water Treatment | 2014
Ahmet Aygün; Bilgehan Nas; Ali Berktay; Havva Ates
AbstractThe operational performance of the sequencing batch reactor (SBR) and sequencing batch biofilm reactor (SBBR) for treating the university campus wastewater was evaluated. The effects of power failure on performance of processes were investigated by comparing chemical oxygen demand (COD) and total suspended solids (TSS) removal, sludge settling properties and microorganism’s morphological properties by using SEM photos. The experiments were carried out at four 2-L reactors made from plexiglas. Three in four reactors were operated as SBBR. SBBRs were filled with the kaldnes biomedia K1 to 40, 50 and 60% of the volume of empty reactor. SBR and SBBRs were operated at 6/24 h cycling periods on a day that consisted of wastewater fill (30 min), reaction (4 h), settling (1 h) and draw (30 min), summed up to 6 h with the hydraulic residence time of 7.5 h. The effect of filling ratio on SBBR performance was also determined. In normal operation, average COD removal rates were calculated as 86, 88.5, 90.6 and...
Environmental Monitoring and Assessment | 2010
Bilgehan Nas; Ali Berktay
Journal of Environmental Management | 2006
Bilgehan Nas; Ali Berktay
Environmental Monitoring and Assessment | 2009
Bilgehan Nas; Hakan Karabörk; Semih Ekercin; Ali Berktay
Archive | 2011
Sehnaz Sener; Erhan Sener; Bilgehan Nas