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Taste and odor problem caused by 2-MIB and geosmin is one of the most common problems seen in water resources. As a result of natural and anthropogenic pollution sources, water resources are polluted, and an earthy-moldy taste and odor occurs in the water. Aquaculture production facilities are the leading anthropogenic sources that cause taste and odor formation in water resources. In this study, it is aimed to determine the best treatment methods that can be used to eliminate the taste and odor problems caused by the formation of 2-MIB and geosmin by using multi-criteria decision making (MCDM) methods in facilities operating in Turkey and where especially rainbow trout is produced. In the study, ozone-based processes, UV-based processes, activated carbon adsorption, aluminum coagulation, sand filtration, chlorination, chlorine dioxide, potassium permanganate, fenton-based processes and photo-fenton processes were used as alternative processes. The criteria chosen for the study were removal performance, reliability and durability, complexity, ease of planned maintenance, ease of construction, use of various chemicals, pre-treatment requirement, by-product formation, and suitability. Analytical hierarchy process (AHP) was used in weighting the criteria in the study, TOPSIS and VIKOR methods were used in ordering the alternatives. According to the results obtained using TOPSIS and VIKOR methods, ozone-based processes were found to be the best treatment method that can be used for the removal of taste and odor components such as 2-MIB and geosmin resulting from rainbow trout production in concrete ponds. [ABSTRACT FROM AUTHOR]

Water management, recycling, and reuse in industrial facilities is a hot topic in today's growing economy because of declining water levels, regulation pressure, and increasing cost of wastewater treatment and supply. In this study, recyclability and direct reuse of washing/bleaching wastewater from reactive dyeing of cotton fabric through advanced oxidation processes (AOPs) (O 3 , UV-O 3 , O 3 -H 2 O 2 , and O 3 -H 2 O 2 -UV) has been investigated. Dyeing trials with treated wastewater were carried out at laboratory scale and no undesirable effects on fabric dyeing quality (ΔE ≤ 1 for color variation) were found for all AOPs. The O 3 -H 2 O 2 -UV process removed COD at a higher rate (55%) than other studied AOPs while color removal was similar (>95%). In pad batch washing/rinsing, 100% water could be recycled (i.e.40% of the total water consumption at facility), reducing fresh water demand for washing operations. Despite this, energy saving, reduced salt consumption and reduction of the cycle time are in favor of recycling/reusing the washing/rinsing effluent. [ABSTRACT FROM AUTHOR]

Antibiotics are important contaminants that have become an increasingly big problem due to the discharge of the receiving environment. The presence of these organic based pollutants in influent wastewater can inhibit the biological processes and resist to degradation in wastewater treatment plants. Moreover, the consumption of agricultural products, irrigated with water containing antibiotic residues, leads to major harmful effects to the human body through the food chain. In this study; firstly, a conventional characterization was made in terms of COD, TOC, SS, color and of antibiotic residue characterization of untreated raw (influent) and biologically treated (effluent) water from domestic and industrial wastewater treatment plants located in the Meriç-Ergene Basin. After that, photocatalytic activity test was run under visible light for selected antibiotics (Erythromycin, Ciprofloxacin, Sulphametoxasol) which were detected by HPLC MS/MS in excess amount. Finally, for the photocatalytic oxidation, a new generation NFC (Nitrogen-Floride-Carbon)-doped titanium dioxide photocatalyst, which has never been studied in the literature before, was prepared according to the sol-gel method without using thermal processing. Photocatalysts were characterized by UV-vis DRS reflectance and Laser Raman Spectra measurements. All other analyzes were made according to the standard methods. Considering the conventional characterization results; investigated domestic wastewaters exhibited moderate characteristics while industrial wastewater samples had strong characteristics in terms of COD, TOC and SS pollution in accordance with the literature. By the way, contrary to expectations, antibiotic residue results have proved that the effluent wastewater contains more antibiotics than the influent. This can be explained by the fact that, some antibiotics in domestic wastewaters are probably already trapped in feces and cannot be purified by conventional systems since they are released after biological treatment, as mentioned similar studies in the literature. Moreover, by means of 7 h NFC-doped photocatalytic oxidation under visible light, beside approximately % 62 to %79 COD and 62%-86% TOC removal, %99 to %100 removal of antibiotic residue was provided. According to these results, domestic and industrial secondary treated wastewaters in Meric-Ergene Basin can be advance treated, succesfully, with NFC-doped photocatalyst to remove antibiotic residues besides conventional pollutants. This result show that Meriç-Ergene discharge criteria determined by Forest and Water Ministry of Turkey can be provided with this new type photocatalytic process and healthy reuse of this river for irrigation will be possible., (Copyright © 2018 Elsevier Ltd. All rights reserved.)