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Showing 1 to 20 of 60 for “"ozonation"”.
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Kinetics and Speciation of Brominated Disinfection by -Products During Ozonation
… 3 x 105 to 1.0 x 106 M-1 •s-1. Although preozonation tended to reduce it, the fast reaction component for HOBr remained even after ozonation. A chemical quenching method using 2-chlorophenol revealed that bromination is a dominant reaction pathway during the reaction between NOM and HOBr.
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Ozonation Systems as a Non-Chemical Alternative for Stored Grain Protection
… scale-up demonstrations using a fixed bed ozonation system and developing a semi-continuous counterflow and a continuous flow ozonation treatment system. The objectives of this research were to determine the efficacy of ozonation to control insect pests without affecting end-use quality; to …
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Evaluation of Bromate Formation and Control using Preformed Monochloramine in Ozonation for Indirect Potable Reuse
… products and endocrine disrupting compounds. Ozonation also increases the biodegradability of recalcitrant organic compounds and inactivates disease-causing microbes. However, bromate, a regulated possible human carcinogen can form when bromide is present due to natural or industrial sources. …
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Catalytic Ozonation of Emerging Pollutants in Water in the Presence of MCM-41 and Fe-MCM-41
… and oxalic acid (OA)) in water in a catalytic ozonation process was investigated in this thesis. This study particularly addresses the preparation of modified catalysts, the role of pH and water matrices on the performance and stability of the catalysts, reaction pathways, and kinetics of the …
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Efficacy of Catalytic Ozonation Advanced Oxidation Processes Compared to Traditional Ozone-Based Advanced Oxidation Processes for Degradation of Recalcitrant Compounds
<p>This study reviews catalytic ozonation AOPs and traditional ozone-based AOPs to compare their efficiency for degradation of ozone-recalcitrant compounds. With the world’s population increasing and water becoming a scarce resource, it is important to improve current water recycling methods. …
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Assessing Biofiltration without Ozonation for Removal of Trihalomethane Precursors in Drinking Water at the Beaver Water District Drinking Water Treatment Plant
<p>Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and …
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Balancing Bromate Formation, Organics Oxidation, and Pathogen Inactivation: The Impact of Bromate Suppression Techniques on Ozonation System Performance in Reuse Waters
Ozonation is an integral process in ozone-biofiltration treatment systems and is beginning to be widely adopted worldwide for water reuse applications. Ozone is effective for pathogenic inactivation and organics oxidation: both increasing assimilable organic carbon for biofiltration and eliminating …
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Effect of Ozone and Ultraviolet Irradiation Treatments on Listeria monocytogenes Populations in Chill Brines
… were conducted to optimize parameters for the ozonation of "fresh" and "spent" brines. These include diffuser design, comparison of kit to standard methods to measure residual ozone, studying the effect of ozone on uridine absorbance and determining presence of residual listericidal activity …
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Disinfection of wastewater for reuse using microchannel plasma ozone generator
… (QMRA) was used to compare microplasma ozonation versus chlorination to disinfect wastewater for landscape irrigational reuse. L. pneumophila, Giardia, and Cryptosporidium parvum were selected as the pathogens. Microplasma-based ozonation was significantly more competitive in …
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Treatability of Dissolved Organic Nitrogen in Truckee Meadows Water Reclamation Facility Using Coagulation or Ozone Treatment
… identify if biological processes downstream of ozonation could remove DON effectively. Ozone oxidation experiments were performed on both filter effluent and final effluent samples. Ozonation alone was able to decrease DON levels; however, the total nitrogen level did not decrease since nitrate …
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The removal of color and DOC from segregated dye waste streams using ozone and Fenton's reagent followed by biotreatment
… chosen for study: molecular ozone, base-promoted ozonation, and Fenton’s reagent (Fe²⁺ and H₂O₂). The ADMI color value of the solutions was used as the primary parameter for color comparison and dissolved organic carbon (DOC) removal was the measure of the effect of biodegradation. Three different …
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Impact of Ozonation on System Performance and Growth Characteristics of Hybrid Striped Bass (Morone chrysops (f) x Morone saxatilis (m)) Reared in Recirculating Aquaculture Systems
… received 25% more freshwater during the trial. Ozonation increased nitrification efficiency which resulted in a 25% reduction in residual ammonia measured per kilogram of feed delivered. Biologically degradable organics (CBOD5) were lowered 45% under ozonation when adjusted for daily feed input. …
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Evaluation of aflatoxin-related products from ozonated corn
This study assessed the efficacy of the ozonation process in degrading aflatoxin in corn, and investigated the chemical reaction between aflatoxin and gaseous ozone. Ozonation (12-13 wt%) totally degraded aflatoxin B1 in a model system. Conversion of aflatoxin into polar compounds was observed …
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Evaluation of ozone treatment, pilot-scale wastewater treatment plant, and nitrogen budget for Blue Ridge Aquaculture
… the need for biological treatment following ozonation. Next, I evaluated a pilot station treatment train including sedimentation, microscreen filtration, fluidized bed denitrification, ozonation, aerobic biological oxidation in a trickling filter, and jar-test chemical flocculation. …
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Application of Ozone in Dissolved Air Flotation (DAF) for Enhanced Removal of TOC and Suspended Solids in Pulp and Paper Wastewaters
… treatment. This thesis studied the effect pre-ozonation has on the DAF process in treating pulp and paper mill secondary effluent. Wastewaters from three mills with different initial water quality parameters were used, especially chemical oxygen demand (COD), turbidity, and color. The most …
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Ozone treatment of a selected textile dyeing and finishing wastewater
… original color of the wastewater was removed by ozonation. COD removals ranging from 20 to 30 percent were also measured. In addition, significant increases in the amounts of suspended solids and turbidity were noted to occur with increased ozonation.
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Investigation of Bromate Formation during Ozone-Biofiltration Treatment Processes for Potable Reuse Application
… non-membrane based alternative technology to RO, ozonation followed by biological activated carbon (BAC) or ozone/BAC is an effective treatment technology for eliminating organic matter from a variety of wastewater effluent streams through oxidation, biological and physical filtration. …
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Ozone-bromide-NOM interactions in water treatment
Ozonation (O$\sb3$) of waters containing bromide (Br$\sp{-}$) results in Br$\sp{-}$ oxidation to first hypobromite ion (OBr$\sp{-}$) and its conjugate acid (HOBr), and eventually bromate (BrO$\sb{3\sp{-}}$), a suspected carcinogen. Natural organic matter (NOM) reads with HOBr/OBr$\sp{-}$ to form …
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Identification and quantification of natural organic matter in the Windhoek operating company water treatment plant in Windhoek, Namibia
… ranging between 2.88 and 4.80 Lmg-1m-1 before ozonation, while these values were less than 2.38 Lmg-1m-1 after ozonation. From these values, it could be concluded that the NOM fractions at the WINGOC treatment plant contained complex mixtures of humic- and non-humic substances with varying …
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An investigation of the effects of ozone in a recirculating aquacultural production system
… system on a commercial scale was investigated. ozonation was responsible for statistically significant differences in all test parameters, including: heterotrophic plate count, total coliforms, fecal coliforms, total solids, and total volatile solids. Results indicated ozone had a significantly …
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