In this study, the degradations of 2,3,4,5,6-pentabromotoluene (PBT), 2,3,4,5,6-pentabromoethyl benzene (PBEB), triclosan (TCS) and gemfibrozil (GFZ) in raw hospital wastewater were investigated with cerium (IV) oxide and titanium (IV) oxide nanoparticles considering the mechanisms of adsorption, photolysis, and photocatalysis with UV-C lamps. The effects of nano-CeO and nano-TiO concentrations, irradiation times, UV light powers and hospital wastewater pH on the photodegradation yields of micropollutants namely PBT, PBEB, TCS and GFZ were investigated throughout photocatalysis. The nano-TiO produced had an anatase phase with crystalline shape with a surface area of 205 m g and an average size of 11.
View Article and Find Full Text PDFBiodegradation requires identification of hydrocarbon degrading microbes and the investigation of psychrotolerant hydrocarbon degrading microbes is essential for successful biodegradation in cold seawater. In the present study, a total of 597 isolates were screened to select psychrotolerant strains and 134 isolates were established as psychrotolerant on the basis of their ability to grow at 7 °C. Hydrocarbon degradation capacities of these 134 psychrotolerant isolate were initially investigated on agar medium containing different hydrocarbons (naphthalene, n-hexadecane, mineral oil) and 47 positive isolates were grown in broth medium containing hydrocarbons at 20 °C under static culture.
View Article and Find Full Text PDFThe treatability of ciprofloxacin (CIP) antibiotic was investigated using a single aerobic, a single anaerobic, an anaerobic/aerobic sequential reactor system, a sonicator and a photocatalytic reactor with TiO2 nanoparticles in a raw hospital wastewater in Izmir, Turkey. The effects of increasing organic loading on the performance of all biological systems were investigated, while the effects of power and time on the yields of sonication and photocatalysis were determined. The maximum COD and CIP yields were 95% and 83% in anaerobic/aerobic sequential reactor system at an HRT of 10 days and at an OLR of 0.
View Article and Find Full Text PDFEnviron Technol
December 2016
Anaerobic biodegradation of mixed non-analogous two substrates was studied in a binary system with and without the primary substrate using an anaerobic multichamber bed (AMCBR). In the binary mixture, the biodegradation of less-degradable oxytetracycline (OTC) was restarted in the presence of more degradable benzo[a]pyrene (BaP) in the initial runs of the AMCBR, but enhanced biodegradation of the more recalcitrant OTC occurs in the later runs of the AMCBR due to enhanced biomass growth on dual substrates without the primary carbon source. The biodegradation yields of the OTC, BaP were discussed with sole-substrate systems and with the dual substrate system in the presence of the primary substrate.
View Article and Find Full Text PDFZirconium dioxide (zirconia, ZrO2)-doped TiO2 (TiO2/ZrO2) nanocomposite was used for the photocatalytic oxidation of pollutant parameters [COD components (CODtotal, CODdissolved and CODinert)], polyphenols (catechol, 3-hydroxybenzoic acid, tyrosol and 4-hydroxybenzoic acid) and total polyaromatic amines [aniline, 4-nitroaniline, o-toluidine and o-anisidine] from the olive mill effluent wastewaters at different operational conditions such as at different mass ratios of ZrO2 (50, 25, 14, 10 and 5 wt%) in the TiO2/ZrO2 nanocomposite, at different TiO2/ZrO2 photocatalyst concentrations (1, 4, 15 and 50 mg/L) and pH values (4.0-7.0-10.
View Article and Find Full Text PDFIn this study, the effects of some additives [manganese (III) oxide (Mn3O4), Cu(+2), Fe(0) and potassium iodate (KIO3)] and some radical scavengers [sodium carbonate (Na2CO3), perfluorohexane (C6F14) and t-butyl alcohol (C4H10O)] on the sonication of olive mill effluent wastewater (OMW) were investigated since the wastewaters of this industry are removed with low efficiencies. The maximum total phenol and total aromatic amines (TAAs) removal efficiencies were 88% and 79%, respectively, at 60°C with only 150 min sonication. The maximum phenol removal was found as 98% with 19 mg L(-1) perfluorohexane and 5 mg L(-1) Fe(0) while the maximum TAAs removal was 99% with 16 mg L(-1) KIO3.
View Article and Find Full Text PDFAn anaerobic multichamber bed reactor (AMCBR) was effective in removing both molasses-chemical oxygen demand (COD), and the antibiotic oxytetracycline (OTC). The maximum COD and OTC removals were 99% in sequential AMCBR/completely stirred tank reactor (CSTR) at an OTC concentration of 300 mg L(-1). 51%, 29% and 9% of the total volatile fatty acid (TVFA) was composed of acetic, propionic acid and butyric acids, respectively.
View Article and Find Full Text PDFA laboratory-scale aerobic activated sludge reactor (AASR) system was employed to investigate the effects of SRT on the removal of three less hydrophobic and six more hydrophobic PAHs in the presence of rhamnolipid (RD), emulsan (EM) and surfactine (SR) biosurfactants. Among the biosurfactants it was found that RD exhibits a better performance than the others in the removal of PAHs. At a RD of 15 mg l(-1) aerobic treatment for 25 days SRT was enough to remove over 90% of the total PAHs, 88% of the COD originating from the inert organics (COD(inert)) and 93% of the COD originating from the inert soluble microbial products (COD(imp)).
View Article and Find Full Text PDFA sequential aerobic completely stirred tank reactor (CSTR) following the anaerobic migrating blanket reactor (AMBR) was used to treat a synthetic wastewater containing 2,4-dinitrotoluene (2,4-DNT). A Box-Wilson statistical experiment design was used to determine the effects of 2,4-DNT and the hydraulic retention times (HRTs) on 2,4-DNT and COD removal efficiencies in the AMBR reactor. The 2,4-DNT concentrations in the feed (0-280 mg/L) and the HRT (0.
View Article and Find Full Text PDFIn this study, the acute toxicities of nitrobenzene (NB) and para nitrophenol (p-NP) were investigated in a high rate sequential anaerobic migrating blanket (AMBR)/aerobic completely stirred tank reactor (CSTR) using Microtox and Daphnia magna tests. After sequential anaerobic and aerobic treatments, the inhibitions in the Microtox bacteria decreased from an initial 78.10-48.
View Article and Find Full Text PDFThe effects of increasing sonication time (60-150min), NaCl (2-18g/l), S(2)O(8)(2-) (2-10mg/l) and 1-butanol (200-600mg/l) concentrations on the destructions of seven polycyclic aromatic hydrocarbons (PAHs) and acute toxicity in a petrochemical industry wastewater in Izmir (Turkey) were investigated. The yields in more hydrophobic PAHs (DahA and BghiP) were as high as in less hydrophobic PAHs (CHR, PHE, PY, BbF and ANT) at 60 degrees C after 150min sonication. The removals in all PAHs increased from 72-78% to 97-99% as the NaCl administration was increased from 1.
View Article and Find Full Text PDFIn this study the interactions between toxicity removals and Kemicetine, COD removals, intermediate products of Kemicetine and COD components (CODs originating from slowly degradable organics, readily degradable organics, inert microbial products and from the inert compounds) were investigated in a sequential anaerobic baffled reactor (ABR)/aerobic completely stirred tank reactor (CSTR) system with a real pharmaceutical wastewater. The total COD and Kemicetine removal efficiencies were 98% and 100%, respectively, in the sequential ABR/CSTR systems. 2-Amino-1 (p-nitrophenil)-1,3 propanediol, l-p-amino phenyl, p-amino phenol and phenol were detected in the ABR as the main readily degradable inter-metabolites.
View Article and Find Full Text PDFThe removal efficiencies of 15 PAHs and some COD components (inert, readily degradable, slowly degradable and metabolic products) from a wastewater taken from a petrochemical industry treatment plant (Izmir, Turkey) have been determined using an aerobic completely stirred tank reactor (CSTR). Addition of rhamnolipid surfactant (15 mg l(-1)) increased the removal efficiencies of PAHs and soluble COD from 72% and 90% to 80% and 99%, respectively. The rhamnolipid treatment caused a significant increase of 5- and 6-ring PAH degradation.
View Article and Find Full Text PDFA laboratory scale anaerobic migrating blanket reactor (AMBR) reactor was operated at nitrobenzene (NB) loading rates increasing from 3.33 to 66.67 g NB/m(3)day and at a constant hydraulic retention time (HRT) of 6 days to observe the effects of increasing NB concentrations on chemical oxygen demand (COD), NB removal efficiencies, bicarbonate alkalinity, volatile fatty acid (VFA) accumulation and methane gas percentage.
View Article and Find Full Text PDFThe effects of increasing nitrobenzene (NB) concentrations and hydraulic retention times (HRT) on the treatment of NB were investigated in a sequential anaerobic baffled reactor (ABR)/aerobic completely stirred tank reactor (CSTR) system. In the first step of the study, the maximum COD removal efficiencies were found as 88% and 92% at NB concentrations varying between 30 mg L(-1) and 210 mg L(-1) in ABR. The minimum COD removal efficiency was 79% at a NB concentration of 700 mg L(-1).
View Article and Find Full Text PDFA laboratory scale anaerobic migrating blanket reactor (AMBR) was operated at different HRTs (1-10.38 days) in order to determine the para-nitrophenol (p-NP) and COD removal kinetic constants. The reactor was fed with 40 mg L(-1)p-NP and 3000 mg L(-1) glucose-COD.
View Article and Find Full Text PDFThe effects of increasing nitrobenzene (NB) concentrations and hydraulic retention time (HRT) on the performance of anaerobic baffled reactor (ABR) and aerobic completely stirred tank reactor (CSTR) were studied. In the first step the NB concentration was increased from 30 to 700 mg/L at constant COD and flowrates. Maximum COD removal efficiencies in ABR varied between 88-92% as NB concentrations increased from 30 to 210 mg/L.
View Article and Find Full Text PDFTo gain more insight into the interactions between anaerobic bacteria and reactor performances (chemical oxygen demand-COD, 2,4 dichlorophenol-2,4 DCP removals, volatile fatty acid-VFA, and methane gas productions) and how they depended on operational conditions the microbial variations in the anaerobic granular sludge from an upflow anaerobic sludge blanket (UASB) reactor treating 2,4 DCP was studied. The study was composed of two parts. In the first part, the numbers of methanogens and acedogens in the anaerobic granular sludge were counted at different COD removal efficiencies.
View Article and Find Full Text PDFThe performance of an upflow anaerobic sludge blanket (UASB) reactor treating 2,4 dichlorophenol (2,4 DCP) was evaluated at different hydraulic retention times (HRTs) using synthetic wastewater in order to obtain the growth substrate (glucose-COD) and 2,4 DCP removal kinetics. Treatment efficiencies of the UASB reactor were investigated at different hydraulic retention times (2-20 h) corresponding to a food to mass (F/M) ratio of 1.2-1.
View Article and Find Full Text PDFThis study investigated the acute toxicity of chemical dye production industry wastewaters by traditional and enrichment toxicity tests and emphasized the importance of toxicity tests in wastewater discharge regulations. The enrichment toxicity tests are novel applications indicating whether there is potential toxicity or stimulation conditions. Different organisms were used including bacteria (floc-Zoogloea ramigera and coliform-Escherichia coli bacteria), algae (Chlorella vulgaris), fish (lepistes-Poecilia reticulate) and protozoan (Vorticella campanula) to represent four tropic levels.
View Article and Find Full Text PDFIn this study, the feasibility of the anaerobic co-digestion of a mixed industrial sludge with municipal solid wastes (MSW) was investigated in three simulated anaerobic landfilling bioreactors during a 150-day period. All of the reactors were operated with leachate recirculation. One of them was loaded only with MSW (control reactor); the second reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:1 (based on dry solid) (Run 1); the third reactor was loaded with mixed industrial sludge and MSW, the weight ratio of the MSW to mixed industrial sludge was 1:2 (based on dry solid) (Run 2).
View Article and Find Full Text PDFIn this study, the effects of COD to NO(3)-N ratio in the feed on PO(4)-P removal was investigated. Maximum PO(4)-P uptake was obtained in the anoxic reactor when the COD to NO(3)-N ratios were between 2 and 3.75.
View Article and Find Full Text PDFThis study investigated the effects of alkalinity on the anaerobic treatment of the organic solid wastes collected from the kitchen of Engineering Faculty in Dokuz Eylul University, Izmir, Turkey and the leachate characteristics treated in three simulated landfill anaerobic bioreactors. All of the reactors were operated with leachate recirculation. One reactor was operated without alkalinity addition.
View Article and Find Full Text PDFJ Environ Sci Health A Tox Hazard Subst Environ Eng
January 2005
In this study, the effects of intermittent aeration on the anaerobic treatment of domestic solid waste and leachate characteristics were investigated in three simulated landfill anaerobic bioreactors. All of the reactors were operated with leachate recirculation and recirculation rate was 300 mL/d. All the reactors were loaded with solid waste having different operational mode.
View Article and Find Full Text PDFAn Upflow Anaerobic Sludge Blanket Reactor/Continuous Stirred Tank Reactor was used sequentially to decolorize and mineralize C.I. Direct Black 38 azo dye (3200 mg/L) in a synthetic wastewater containing glucose as co-substrate.
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