WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394

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Author: search.filters.author.Uzal, NigmetWoS Q: search.filters.wosQuartile.Q2

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Now showing 1 - 5 of 5
  • Article
    Citation - WoS: 29
    Citation - Scopus: 32
    Wind Farm Site Selection Using GIS-Based Multicriteria Analysis With Life Cycle Assessment Integration
    (Springer Heidelberg, 2024-01-19) Demir, Abdullah; Dincer, Ali Ersin; Ciftci, Cihan; Gulcimen, Sedat; Uzal, Nigmet; Yilmaz, Kutay
    The sustainability of wind power plants depends on the selection of suitable installation locations, which should consider not only economic and technical factors including manufacturing and raw materials, but also issues pertaining to the environment. In the present study, a novel methodology is proposed to determine the suitable locations for wind turbine farms by analyzing from the environmental perspective. In the methodology, the life cycle assessment (LCA) of wind turbines is incorporated into the decision process. The criteria are ranked using analytical hierarchy process (AHP). The study area is chosen as the western region of Turkiye. The obtained suitability map reveals that wind speed is not the sole criterion for selecting a site for wind turbine farms; other factors, such as bird migration paths, distance from urban areas and land use, are also crucial. The results also reveal that constructing wind power plants in the vicinity of Izmir, canakkale, Istanbul, and Balikesir in Turkiye can lead to a reduction in emissions. Izmir and its surrounding area show the best environmental performance with the lowest CO2 per kilowatt-hour (7.14 g CO2 eq/kWh), to install a wind turbine due to its proximity to the harbor and steel factory across the study area. canakkale and the northwest region of Turkiye, despite having high wind speeds, are less environmentally favorable than Izmir, Balikesir, and Istanbul. The findings of LCA reveal that the nacelle and rotor components of the wind turbine contribute significantly (43-97%) to the environmental impact categories studied, while the tower component (0-36%) also has an impact.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Surface Coating of Polyamide Reverse Osmosis Membranes With Zwitterionic 3-(3,4 (l-DOPA) for Forward Osmosis
    (Wiley, 2019-03-27) Saki, Seda; Uzal, Nigmet
    To overcome low permeability and fouling problems of membranes used in FO processes, modification is needed to improve the hydrophilicity, permeability and selectivity of membranes. In this work, thin film composite (TFC) commercial polyamide RO membranes (BW30-LE, SW30-HR, AG and AC) were functionalized with zwitterionicl-DOPA. The effect ofl-DOPA on the morphology of membranes was determined via SEM, FT-IR, AFM and contact angle analysis. Thel-DOPA modified BW30-LE membrane showed excellent properties with 46 degrees contact angle and 3.8 L/m(2)hbar water permeability and 0.83 L/m(2)h salt permeability. Although,l-DOPA modified BW30-LE membrane had the highest water flux and hydrophilicity,l-DOPA modified SW30-HR membrane showed higher FO flux with 9.38 L/m(2)h than BW 30 membrane with 3.5 L/m(2)h at 50 g/L NaCl draw solution. Introducing hydroxyl and carboxyl ionic groups on the membrane surface withl-DOPA coating enhanced the FO performance and water permeability which provide a new insight in FO applications.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    Robust Multicriteria Sustainability Assessment in Urban Transportation
    (ASCE-Amer Soc Civil Engineers, 2023-06) Gulcimen, Sedat; Aydogan, Emel Kizilkaya; Uzal, Nigmet
    Developing methodologies to facilitate the planning of sustainable transport systems for decision makers (DMs) is becoming more critical. This study proposed a methodological framework for sustainable urban transportation to make decisions during urban transportation's design and planning stages. Urban transportation alternatives were evaluated by sustainability indicators that considered a triple bottom line approach's environmental, economic, and social aspects. To choose the best alternative sustainable transportation scenarios, two multicriteria decision-making (MCDM) methods, for example, a hesitant fuzzy analytical hierarchy process (HF-AHP) and multiple attribute utility model (MAUT), were integrated. First, eight sustainable transportation indicators that considered data availability from the transport sector were selected. The weights of the selected indicators were calculated using an HF-AHP. These indicators included carbon dioxide (CO2) emissions, energy consumption, depletion of nonrenewable resources, operational and maintenance costs, fuel and taxes, the number of fatalities or injuries, and motor vehicles for public transport per 10,000 population. Finally, sensitivity analysis was applied to validate the robustness. Based on HF-AHP results, the number of fatalities or injuries was the most significant among the eight indicators, with a 0.158 normalized weight (N-i). The results of this integrated methodology highlighted that Alternative 11, which was dominated by low-motorized vehicles (low-MVs), was the best sustainable alternative and Alternative 1 was the worst sustainable alternative, which was dominated by high-MVs with 0.69 and 0.27 total utility values, respectively. Low-motorized urban transportation alternatives showed higher sustainable performances than the motorized and high-motorized alternatives. This study proposed a novel and robust methodology for decisions on sustainable urban transportation projects and renovating current urban transportation systems.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Pre-Concentration of Municipal Wastewater Using Flocculation-Assisted Direct Ceramic Microfiltration Process: Optimization of Operational Conditions
    (Springer int Publ Ag, 2022-10) Ozcan, Ozlem; Sahinkaya, Erkan; Uzal, Nigmet
    Direct ceramic microfiltration (DCMF) is an effective technology to pre-concentrate organic matter (OM) for the subsequent anaerobic energy-recovering processes and a fast, cost-effective, easy treatment process for municipal wastewater. The major problem in DCMF is the rapid fouling of the membrane. In this study, to maximize OM recovery rates and prevent membrane fouling, the DCMF process was alternately paired with dosing of a cationic polyacrylamide (PAM) flocculant and chemically enhanced primary sedimentation (CEPS). The DCMF process tested in three stages: (i) optimization of flocculant concentration (0.5, 1, 1.5, and 2 mg/L PAM) and dosing point, (ii) optimization of operational conditions (pH, filtration/backwash duration, flux, and recovery rate) to control membrane fouling, and (iii) long-term operation of the DCMF process. The influence of PAM dosage points on DCMF fouling behavior was explored, and system operating parameters in terms of OM recovery and TMP change were optimized. The CEPS + DCMF setup was discovered to be a potential option for overcoming fouling. The highest chemical oxygen demand (COD) was 520 +/- 20 mg/L in the concentrated wastewater using CEPS + DCMF experiments for 0.5 mg/L PAM. The highest OM pre-concentration was achieved at 90% recovery rate. After the optimization, COD concentration in the concentrate of the DCMF process reached 822 mg/L for the long-term (20 days) operation. The net potential energy production was calculated as 0.28 kWh/m(3) considering the theoretical COD of 1432 mg/L in the concentrate stream. As a novel approach, the CEPS + DCMF process can be used in place of conventional municipal wastewater treatment processes due to its acceptable OM removal performance, simple operation, small footprint, and potential energy generation.
  • Article
    Citation - WoS: 46
    Citation - Scopus: 52
    Life Cycle Assessment of Lightweight Concrete Containing Recycled Plastics and Fly Ash
    (Taylor & Francis Ltd, 2020-06-05) Ersan, Yusuf Cagatay; Gulcimen, Sedat; Imis, Tuba Nur; Saygin, Osman; Uzal, Nigmet
    Researchers put significant effort to decrease the environmental impact of concrete by using industrial by-products as an alternative binder. However, the considerable environmental impact still exists due to the consumption of natural resources as aggregates. Natural aggregates are the most used resources by volume in the construction sector. Therefore, it is necessary to investigate by-products as an alternative to natural aggregates as well. This study presents the environmental impact of lightweight concrete (LWC) produced by replacing natural aggregates with recycled waste plastic (polyethylene) (RWP) and partially replacing Portland cement with Class F fly ash (FA). Life Cycle Assessment (LCA) was performed to compare a conventional LWC, containing pumice as natural aggregate and Portland cement as a binder, with green LWC, containing 30% RWP as pumice replacement and 20% FA as cement replacement. These scenarios were evaluated in terms of global warming potential, abiotic depletion, ozone layer depletion, terrestrial ecotoxicity, photochemical oxidation, acidification and eutrophication. LCA was coupled with mechanical tests at 7 days and 28 days. RWPs were found to be an environment-friendly replacement material for natural lightweight aggregates with an overall decrease in all CML-IA impacts except eutrophication. Tested green mix design also provided sufficient strength for nonstructural applications.