Environmental Engineering / Çevre Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/4321

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  • Article
    Citation - Scopus: 5
    Effect of Covid-19 Pandemic on Ambient Air Quality and Excess Risk of Particulate Matter in Turkey
    (2021) Gören, Ayşegül Yağmur; Genişoğlu, Mesut; Genişoğlu, Mesut; Sofuoğlu, Sait Cemil; Gören, Ayşegül Yağmur; Sofuoğlu, Sait Cemil; Ökten, Hatice Eser; 03.07. Department of Environmental Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    The COVID-19 pandemic, which has reached 4 million global cases as of March 10, 2020, has become a worldwide problem. Turkey is one of the most affected (9th in the world) country with 139 771 cases. An intermittent curfew policy that differ for three age groups, and an intercity travel ban varying within the country have been implemented. The effects of changes in social life and industrial activity in terms of environmental pollution are not yet known. The short-term effects on PM2.5, PM10, SO2, NO2, NO, NOx, O3 and CO concentrations measured at 51 air quality measurement stations (AQMS) in 11 cities in March – April period of 2020 were statistically compared with that of the previous year. While PM2.5 (9/14 AQMS) and PM10 (29/35 AQMS) concentrations were not significantly affected, NO (12/24 AQMS), NO2 (20/29 AQMS), NOX (17/25 AQMS) concentrations were decreased, SO2 concentrations at half of the AQMSs (11/25) did not show a significant change. There were stations at which higher pollutant concentrations were measured in the study period in 2020 compared to that of 2019. Excess risks associated with PM2.5 and PM10 were estimated to be variable, albeit with a small difference. In conclusion, the heterogeneous actions taken in response to the COVID-19 pandemic resulted in mixed effects on ambient air quality.
  • Article
    Methylene Blue Removal of Fixed-Bed Column Reactor With Pumice and Nzvi-Pumice: Experimental and Modeling Study
    (Süleyman Demirel Üniversitesi, 2019) Genişoğlu, Mesut; Gören, Ayşegül Yağmur; Gören, Ayşegül Yağmur; Recepoğlu, Yaşar Kemal; Ökten, Hatice Eser; Genişoğlu, Mesut; Recepoğlu, Yaşar Kemal; Ökten, Hatice Eser; 03.07. Department of Environmental Engineering; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Nano zero-valent iron (nZVI) emerges as a low cost and eco-friendly adsorbent to treat textile wastewater, which is rich in dye content. However nZVI particles can easily agglomerate in aqueous environment due to electrostatic interaction, decreasing their treatment efficiency. Therefore pumice, a low-cost and naturally found porous material with lower specific surface area (2m2/gr), can be used as support material to reduce agglomeration of nZVI. Treatment efficiencies of pumice/nZVI packing (10:0 and 9:1 (w/w)) in column reactor for specified initial methylene blue concentrations (25, 50, 75 and 100 mg/L) were investigated in this study. Adsorption capacities of the adsorbents were calculated as 2.8 and 4.2 mg/g-adsorbent, respectively at 100 mg/L initial methylene blue concentration. Mixed bed column performed significantly better than its pumice-only counterpart for low initial concentrations. Thomas adsorption model was applied to experimental results with a moderate to high predictive power.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Use of Nano Zero-Valent Iron Coated Coffee Grounds for Removal of Zn(ii) and Ni(ii) From Aqueous Solutions
    (Desalination Publications, 2019) Gören, Ayşegül Yağmur; Genişoğlu, Mesut; Ökten, Hatice Eser; Genişoğlu, Mesut; Gören, Ayşegül Yağmur; 03.07. Department of Environmental Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    This research investigates the adsorption capacity of a novel composite material, namely nano zero-valent iron coated coffee grounds (nZVI-CG), for removal of zinc (Zn) and nickel (Ni). nZVI particles were synthesized and immobilized to the surface of waste coffee grounds (CG) using the ultrasonic-assisted liquid phase method. Characterization of synthesized nZVI-CG composite and bare CG showed that nZVI coating has increased the surface area significantly. Batch tests were conducted to examine the effects of pH, reaction time and initial metal concentrations on Zn2+ and Ni2+ removal. At an initial metal concentration of 10 mg-Ni/L and 10 mg-Zn/L, nZVI-CG removal rates for Zn2+ and Ni2+ were observed as 98.89% and 97.29%, respectively; while removal rates of bare CG have remained at 51% (Zn2+) and 48.1% (Ni2+). Moreover, acidic conditions were observed to deteriorate Ni2+ and Zn2+ adsorption since most functional groups of the metals were protonated. Increasing initial nickel and zinc concentrations decreased removal rates. While the model fittings improved with increasing pH, in the case of nZVI-CG, Langmuir isotherm gave the best fits for Ni2+ and Zn2+ at pH 5 and 7. Also, our experimental results followed the pseudo-second-order kinetic model, regardless of the used adsorbent. Consequently, our results showed that nZVI-CG composite material is a promising alternative adsorbent for pilot scale metal removal/recovery applications.
  • Conference Object
    Groundwater Pollution by Nitrate From Agricultural Fertilizers: the Case of Menemen Basin (aegean Region, Turkey)
    (İZSU, 2017) Gören, Ayşegül Yağmur; Genişoğlu, Mesut; Ökten, Hatice Eser; Ökten, Hatice Eser; Baba, Alper; Baba, Alper; Gören, Ayşegül Yağmur; Genişoğlu, Mesut; 03.07. Department of Environmental Engineering; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Groundwater is an essential drinking water source in Menemen sub­basin of İzmir city, Turkey. The aim of this study was to investigate the groundwater contamination by nitrates of agricultural lands. For this purpose, we evaluated variations of groundwater pH, redox potential, electrical conductivity (EC), major anions (NO3, Cl, SO4, HCO3 and CO3) and cations (Na, K, Ca and Mg). A statistical correlation procedure and piper diagram for hydrogeochemistry of groundwater were also applied. Nitrate levels were found to be higher around agricultural areas. Also EC values and Cl­ were measured to be higher as proximity to coastal areas increased, indicating seawater intrusion. Agricultural activities and excessive freshwater withdrawal were shown to impair groundwater quality and quantity at Menemen sub­basin.