Environmental Engineering / Çevre Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4321
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Article Pomza ve Nsdd-pomza ile Sabit Yataklı Kolon Reaktörde Metilen Mavisi Giderimi: Deneysel ve Modelleme Çalışması(2019) Balcı, Esin; Ökten, Hatice Eser; Genişoğlu, Mesut; Recepoğlu, Yaşar Kemal; Gören, Ayşegül YağmurNano sıfır değerlikli demir (nSDD) yüksek renk konsantrasyonlarına sahip tekstil atıksularının arıtımında ekonomik ve çevre dostu bir adsorban olarak ortaya çıkmaktadır. Ancak nSDD partikülleri sulu çözeltilerde elektrostatik etkileşimler sebebiyle kolayca topaklaşmakta ve bu da arıtma veriminin düşmesine neden olmaktadır. Dolayısıyla düşük maliyetli, doğal poröz yapıda ve ortalama 2m2/gr spesifik yüzey alanına sahip pomza, nSDD topaklaşmasını önleyici bir malzeme olarak kullanılabilir. Bu çalışmada sadece pomza ve pomzanSDD (ağırlıkça 9:1) karışımının kullanıldığı kolon reaktörde 25, 50, 75 ve 100 mg/L metilen mavisi konsantrasyonları için arıtma verimleri incelenmiştir. Pomzanın ve pomza-nSDD karışımının 100 mg/L metilen mavisi deneyindeki toplam kapasiteleri sırasıyla 2,8 ve 4,2 mg/g-adsorban olarak bulunmuştur. Özellikle düşük konsantrasyonlarda, pomza-nSDD karışımının arıtma performansını önemli ölçüde arttırdığı görülmüştür. Thomas modeli deneysel verilere uygulanmış ve modelin öngörü gücünün düşük konsantrasyonda yüksekken, yüksek konsantrasyonlarda ortalama olduğu kanısına varılmıştır.Article Yüzme Havuzlarında Karbon Bazlı Dezenfeksiyon Yan Ürünlerinin Oluşumu(Dokuz Eylül Üniversitesi, 2017) Harman, B. İlker; Tanaçan, Ertaç; Genişoğlu, Mesut; Kaplan, Ş. Şule; Ateş, Nuray; Yiğit, Nevzat Ö.; Kanan, Amer A.S.Bu çalışmada ülkemiz literatüründe ilk defa yer alacak ve oldukça önemli bir konu olan yüzme havuzlarındaki dezenfeksiyon yan ürünlerinin (DYÜ) türleri, DYÜ oluşumuna etki eden faktörler ve DYÜ'lerin sağlık etkileri konusunda bir derleme yapılmıştır. İçme suyu şebekesi ve yüzme havuzlarındaki patojen mikroorganizmaların engellenebilmesi amacıyla birçok dezenfektan kullanılmaktadır. Yüzme havuzlarında genellikle klor bazlı dezenfektanlar kullanılırken, bromlu dezenfektanlar da dezenfeksiyon için tercih edilmektedir. Havuz suyundaki organik madde kaynakları; i) doldurma suyunda bulunan doğal organik maddeler (DOM) ve ii) yüzücülerden gelen organik yüklemelerdir. Yüzme havuzları özelinde yüzücülerden kaynaklı daimi organik yükleme ve sürekli dezenfeksiyon sonucu (organik maddelerin oksidantlar/dezenfektanlar ile reaksiyonu sonucunda) mutajenik ve kanserojenik olmalarından şüphelenilen DYÜ oluşumu içme sularındakine nazaran daha fazladır. Trihalometan (THM) ve haloasetik asitler (HAA), havuz suyunda en sık karşılaşılan yan ürünlerdir. THM gibi uçucu olan yan ürünler sadece yüzme suyunda değil, havada da oldukça yüksek konsantrasyonlarda bulunabilmektedir. Bu yan ürünlerin oluşum mekanizmalarının bilinmesi ve kontrol altına alınması, yüzücüler ve bilhassa havuz çalışanlarının sağlığına olan etkilerinin en aza indirilmesi bağlamında önem arz etmektedir. Oluştuktan sonra giderilmesi zor ve maliyetli olan DYÜ'lerin oluşumunda etkili öncüllerin belirlenmesi ve kontrolü ile uygun dezenfektan türünün kullanılmasıyla yüzme havuzlarındaki DYÜ oluşumları azaltılabilir.Article Citation - WoS: 26Citation - Scopus: 26Multi-Route - Multi-Pathway Exposure To Trihalomethanes and Associated Cumulative Health Risks With Response and Dose Addition(Academic Press Inc., 2019) Genişoğlu, Mesut; Ergi Kaytmaz, Ceyda; Sofuoğlu, Sait CemilCumulative health risk estimation for exposure to mixtures is a current issue, which would present a useful tool for environmental and public health management. Cumulative risks were estimated with response and dose addition methods for individual multi-route - multi-pathway exposure to trihalomethanes and associated carcinogenic toxic risks in Izmir, Turkey. Exposure levels were estimated for ingestion, dermal, and inhalation routes using measured tap water and bottled water THM concentrations. Drinking, showering, hand and dish washing were the considered pathways. THM concentrations in air during the showering were modeled with two-resistance theory using tap water concentration data. The estimated carcinogenic risk levels for ingestion route were in the range of safe (< 10(-6)) to low priority (< 10(-4)), for dermal route all were in the safe zone (< 10(-6)), and for inhalation route were in the range of safe to high priority (> 10(-4)) zones, indicating ingestion and inhalation routes were of similar significance ahead of dermal exposure. Cumulative carcinogenic risks of THM compounds were estimated using simple (response) addition and dose addition using cumulative relative potency factor (CRPF) methods. CRPF method estimated the risks at lower levels compared to the simple addition, which originated from the use two different risk factor values for the index chemical in the method. Cumulative chronic-toxic risks were also assessed, rendering below the threshold risk levels for all routes. This study showed that multi-route - multi-pathway exposure assessment and cumulative risk assessment should together be considered for better environmental and public health management.Article Citation - WoS: 15Citation - Scopus: 19Brominated Flame Retardants in a Computer Technical Service: Indoor Air Gas Phase, Submicron (pm1) and Coarse (pm10) Particles, Associated Inhalation Exposure, and Settled Dust(Elsevier Ltd., 2019) Genişoğlu, Mesut; Sofuoğlu, Aysun; Kurt Karakuş, Perihan Binnur; Birgül, Aşkın; Sofuoğlu, Sait CemilBrominated flame retardants (BFRs) are found in multi-media indoors, therefore, may pose serious risks to human health. This study investigated the occurrence of BFRs in particulate matter (PM1 and PM10) and gas phase by active and passive sampling, and settled dust to estimate potential exposure in a computer technical service. Polybrominated diphenyl ethers (PBDEs) and their alternatives (novel BFRs, NBFRs) were studied. PM and gas phase were collected on glass fiber filters and polyurethane foam plugs, respectively, and analyzed with a GC/MS after extraction, clean-up, and concentration. Inhalation exposure of the staff was estimated based on the measured concentrations using Monte Carlo simulation. BDE-209 was the dominating PBDE congener in all media while bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate and 1,2-bis(2,4,6-tribromophenoxy)ethane were those of NBFRs. Submicron particulate matter (PM1) BFR levels constituted about one half of the PM10-associated concentrations, while average PM10 mass concentration (69.9 μg m−3) was nine times that of PM1 (7.73 μg m−3). Calculated log10 dust-gas and PM-gas partitioning coefficients ranged from −5.03 to −2.10, −2.21 to −0.55, and −2.26 to −1.04 for settled dust, PM10, and PM1, respectively. The indoor/outdoor concentration ratios were >1 for all compounds indicating the strength of indoor sources in the service. The estimated potential inhalation exposures, for future chronic-toxic and carcinogenic risk assessments, indicated that the levels of gas-phase and PM1-associated exposures were similar at approximately one half of PM10-associated levels. Results of this study indicate that the occurrence of BFRs in all studied media should be taken into consideration for occupational health mitigation efforts.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; Balcı, Esin; Recepoğlu, Yaşar Kemal; Ökten, Hatice EserNano 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: 3Citation - Scopus: 4Use 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 EserThis 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; Balcı, Esin; Ökten, Hatice Eser; Baba, AlperGroundwater 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.