A Competitive Study Using UV and Ozone with H2O2 in Treatment of Oily Wastewater

In this study, ultraviolet (UV), ozone techniques with hydrogen peroxide oxidant were used to treat the wastewater which is produced from South Baghdad Power Station using lab-scale system. From UV-H2O2 experiments, it was shown that the optimum exposure time was 80 min. At this time, the highest removal percentages of oil, COD, and TOC were 84.69 %, 56.33 % and 50 % respectively. Effect of pH on the contaminants removing was studied in the range of (2-12). The best oil, COD, and TOC removal percentages (69.38 %, 70 % and 52 %) using H2O2/UV were at pH=12. H2O2/ozone experiments exhibited better performance compared to the H2O2/UV experiments. The results showed that 20 min was the best exposure time with removal percentages of 89.79 %, 83.33 % and 70% for oil, COD and TOC, respectively, and the optimum value of pH was at pH=8, where the pollutants removal percentages (i.e. 74.48 %, 80 % and 73.33 % respectively for the same previous pollutants). H2O2/ozone experiments showed better removal efficiency than the H2O2/UV experiments.

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Effect of pH and hydrogen peroxide on aldehyde formation in the ozonation process

Journal of Water Supply Research and Technology—AQUA ◽

10.2166/aqua.1998.10 ◽

1998 ◽

Vol 47 (2) ◽

pp. 50-56 ◽

Cited By ~ 2

Author(s):

Jacek Nawrocki ◽

Iwona Kalkowska

Keyword(s):

Hydrogen Peroxide ◽

Effect Of Ph ◽

Ozonation Process

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The Efficacy of Whole Oyster Shells for Removing Copper, Zinc, Chromium, and Cadmium Heavy Metal Ions from Stormwater

Sustainability ◽

10.3390/su13084184 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4184

Author(s):

Zhiying Xu ◽

Caterina Valeo ◽

Angus Chu ◽

Yao Zhao

Keyword(s):

Surface Area ◽

Hexavalent Chromium ◽

Removal Efficiency ◽

Exposure Time ◽

Food Waste ◽

Positive Relationship ◽

Copper Ions ◽

Zinc Ions ◽

Cadmium Ions ◽

Initial Concentration

This research investigates the use of a common food waste product for removing four different types of metals typically found in stormwater. Whole, unprocessed oyster shells are explored for use in stormwater management infrastructure that addresses water quality concerns. The role of the shells’ surface area, exposure time, and the solution’s initial concentration on the removal efficiency were examined. Beaker scale experimental results demonstrated very good efficiency by the oyster shells for removing copper ions (80–95%), cadmium ions (50–90%), and zinc ions (30–80%) but the shells were not as effective in removing hexavalent chromium (20–60%). There was a positive relationship between initial concentration and removal efficiency for copper and zinc ions, a negative relationship for hexavalent chromium, and no relationship was found for cadmium ions. There was also a positive relationship between surface area and removal efficiency, and exposure time and removal efficiency. However, after a certain exposure time, the increase in removal efficiency was negligible and desorption was occasionally observed. A mid-scale experiment to mimic real-world conditions was conducted in which continuous inflow based on a 6-h design storm was applied to 2.7 kg of whole, unprocessed oyster shells. The shells provided an 86% and an 84% removal efficiency of cadmium and copper ions, respectively, in one day of hydraulic retention time. No removal was observed for hexavalent chromium, and zinc ion removal was only observed after initial leaching. This work has significant implications for sustainable stormwater infrastructure design using a material commonly found in municipal food waste.

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Sanitation of fresh green asparagus and green onions inoculated with Salmonella

Czech Journal of Food Sciences ◽

10.17221/138/2008-cjfs ◽

2009 ◽

Vol 27 (No. 6) ◽

pp. 454-462 ◽

Cited By ~ 7

Author(s):

M.A. Martínez-Téllez ◽

F.J. Rodríguez-Leyva ◽

I.E. Espinoza-Medina ◽

I. Vargas-Arispuro ◽

A.A. Gardea ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Lactic Acid ◽

Exposure Time ◽

Salmonella Enterica ◽

Fresh Produce ◽

Clean Water ◽

Effective Agent ◽

Serovar Typhimurium ◽

Postharvest Handling ◽

Green Asparagus

The absence of good agricultural and manufacturing practices in the production and postharvest handling of fresh produce, such as green asparagus or green onions increase the contamination risk by biological hazards like Salmonella. The objective of this work was to investigate the efficacy of chlorine (200 and 250 ppm), hydrogen peroxide (1.5% and 2%), and lactic acid (1.5% and 2%) sanitisers during different exposure times (40, 60, and 90 s) on the reduction of Salmonella enterica subspecie enterica serovar Typhimurium in inoculated fresh green asparagus and green onions. Washing with clean water only reduced < 1 log10 CFU/g in both vegetables. The most effective sanitiser evaluated for fresh green asparagus and green onions disinfection appeared to be 2% lactic acid reducing Salmonella growth close to 3 log10 CFU/g. Hydrogen peroxide was the least effective agent for Salmonella Typhimurium reduction. No effect was observed of the exposure time of inoculated product to sanitiser up to 90 seconds. These results confirm that lactic acid could be used as an alternative for fresh green asparagus and green onions sanitation.

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Janus amphiphilic carbon nanotubes as Pickering interfacial catalysts for the treatment of oily wastewater by selective oxidation with hydrogen peroxide

Catalysis Today ◽

10.1016/j.cattod.2019.07.012 ◽

2020 ◽

Vol 356 ◽

pp. 205-215 ◽

Cited By ~ 5

Author(s):

Jose L. Diaz de Tuesta ◽

Bruno F. Machado ◽

Philippe Serp ◽

Adrián M. T. Silva ◽

Joaquim L. Faria ◽

...

Keyword(s):

Carbon Nanotubes ◽

Hydrogen Peroxide ◽

Selective Oxidation ◽

Oily Wastewater

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Post-treatment of tannery wastewater using pilot scale horizontal subsurface flow constructed wetlands (polishing)

Water Science & Technology ◽

10.2166/wst.2017.613 ◽

2017 ◽

Vol 77 (4) ◽

pp. 988-998 ◽

Cited By ~ 2

Author(s):

Tadesse Alemu ◽

Andualem Mekonnen ◽

Seyoum Leta

Keyword(s):

Removal Efficiency ◽

Batch Reactor ◽

Subsurface Flow ◽

Oxygen Demand ◽

Pilot Scale ◽

Surface Flow ◽

Tannery Wastewater ◽

Treated Effluent ◽

Horizontal Subsurface Flow ◽

Pollutants Removal

Abstract In the present study, a pilot scale horizontal subsurface flow constructed wetland (CW) system planted with Phragmites karka; longitudinal profile was studied. The wetland was fed with tannery wastewater, pretreated in a two-stage anaerobic digester followed by a sequence batch reactor. Samples from each CW were taken and analyzed using standard methods. The removal efficiency of the CW system in terms of biological oxygen demand (BOD), chemical oxygen demand (COD), Cr and total coliforms were 91.3%, 90%, 97.3% and 99%, respectively. The removal efficiency for TN, NO3− and NH4+-N were 77.7%, 66.3% and 67.7%, respectively. Similarly, the removal efficiency of SO42−, S2− and total suspended solids (TSS) were 71.8%, 88.7% and 81.2%, respectively. The concentration of COD, BOD, TN, NO3−N, NH4+-N, SO42 and S2− in the final treated effluent were 113.2 ± 52, 56 ± 18, 49.3 ± 13, 22.75 ± 20, 17.1 ± 6.75, 88 ± 120 and 0.4 ± 0.44 mg/L, respectively. Pollutants removal was decreased in the first 12 m and increased along the CW cells. P. karka development in the first cell of CW was poor, small in size and experiencing chlorosis, but clogging was higher in this area due to high organic matter settling, causing a partial surface flow. The performance of the pilot CW as a tertiary treatment showed that the effluent meets the permissible discharge standards.

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Treatment of local scrubber wastewater for semiconductor by using photo-catalytic ozonation

Water Science & Technology ◽

10.2166/wst.2009.274 ◽

2009 ◽

Vol 59 (11) ◽

pp. 2281-2286 ◽

Cited By ~ 2

Author(s):

Chung-Yi Chou ◽

Chien-Pin Huang ◽

Neng-Chou Shang ◽

Yue-Hwa Yu

Keyword(s):

Ion Exchange ◽

Removal Efficiency ◽

Removal Rate ◽

Catalytic Ozonation ◽

Acidic Condition ◽

Buffer Solution ◽

Toc Removal ◽

Pre Treatment ◽

Alkaline Buffer Solution

This study investigates the oxidation of local scrubber wastewater (LSW) from semiconductor manufacture by using ozonation, catalytic ozonation (ozone/Al2O3 and ozone/TiO2–Al2O3), and photo-catalytic ozonation (UV/TiO2–Al2O3, ozone/UV and ozone/UV/TiO2–Al2O3). The results show that catalyst Al2O3 and TiO2–Al2O3 promotes the TOC removal under the condition of neutral or alkaline buffer solution during catalytic ozonation of LSW. The Al2O3 induces highest promotion in TOC removal efficiency, which is higher than ozone alone by 26% TOC removal under alkaline buffer solution. However, TiO2–Al2O3 and Al2O3 cannot display the promotion in TOC removal under acidic condition. In addition, a pre-treatment of anion ion-exchange is employed and the result indicates that decreasing the anion ions concentration before AOPs can imply higher TOC removal during AOPs of LSW. In this study, ozone/UV under raw LSW acidic condition and ozone/Al2O3 under alkaline buffer solution present 95% and 88% TOC removal rate respectively and show the higher TOC removal efficiency than other AOPs. Therefore, these two kinds of AOP can serve as the very viable AOP methods in the LSW reclamation for semiconductor.

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Treatment of oilfield wastewater by combined process of micro-electrolysis, Fenton oxidation and coagulation

Water Science & Technology ◽

10.2166/wst.2017.486 ◽

2017 ◽

Vol 76 (12) ◽

pp. 3278-3288 ◽

Cited By ~ 3

Author(s):

Zhenchao Zhang

Keyword(s):

Reaction Time ◽

Removal Efficiency ◽

Treatment Process ◽

Cod Removal ◽

Fenton Oxidation ◽

Oily Wastewater ◽

Optimum Conditions ◽

Combined Process ◽

Cod Removal Efficiency ◽

Optimized Conditions

Abstract In this study, a combined process was developed that included micro-electrolysis, Fenton oxidation and coagulation to treat oilfield fracturing wastewater. Micro-electrolysis and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance organic components gradability, respectively. Orthogonal experiment were employed to investigate the influence factors of micro-electrolysis and Fenton oxidation on COD removal efficiency. For micro-electrolysis, the optimum conditions were: pH, 3; iron-carbon dosage, 50 mg/L; mass ratio of iron-carbon, 2:3; reaction time, 60 min. For Fenton oxidation, a total reaction time of 90 min, a H2O2 dosage of 12 mg/L, with a H2O2/Fe2+ mole ratio of 30, pH of 3 were selected to achieve optimum oxidation. The optimum conditions in coagulation process: pH, cationic polyacrylamide dosage, mixing speed and time is 4.3, 2 mg/L, 150 rpm and 30 s, respectively. In the continuous treatment process under optimized conditions, the COD of oily wastewater fell 56.95%, 46.23%, 30.67%, respectively, from last stage and the total COD removal efficiency reached 83.94% (from 4,314 to 693 mg/L). In the overall treatment process under optimized conditions, the COD of oily wastewater was reduced from 4,314 to 637 mg/L, and the COD removal efficiency reached 85.23%. The contribution of each stage is 68.45% (micro-electrolysis), 24.07% (Fenton oxidation), 7.48% (coagulation), respectively. Micro-electrolysis is the uppermost influencing process on COD removal. Compared with the COD removal efficiency of three processes on raw wastewater under optimized conditions: the COD removal efficiency of single micro-electrolysis, single Fenton oxidation, single coagulation is 58.34%, 44.88% and 39.72%, respectively. Experiments proved the effect of combined process is marvelous and the overall water quality of the final effluent could meet the class III national wastewater discharge standard of petrochemical industry of China (GB8978-1996).

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Impacts of Changing Operational Parameters of In Situ Chemical Oxidation (ISCO) on Removal of Aged PAHs from Soil

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2012-0223 ◽

2012 ◽

Vol 15 (2) ◽

Cited By ~ 1

Author(s):

Paula Cajal-Mariñosa ◽

Ruth G. de la Calle ◽

F. Javier Rivas ◽

Tuula Tuhkanen

Keyword(s):

Hydrogen Peroxide ◽

Removal Efficiency ◽

Contaminated Soil ◽

Chemical Oxidation ◽

Contaminant Removal ◽

Operational Parameters ◽

In Situ Chemical Oxidation ◽

Different Types ◽

Wood Impregnation

AbstractThe removal efficiency of two different types of peroxide addition, catalyzed hydrogen peroxide (CHP) and sodium percarbonate (SPC) were compared on a highly PAH-contaminated soil from a wood impregnation site. In an attempt to simulate real in situ reagents delivery, experiments have been carried out in acrylic columns. The main parameters affecting contaminant removal were the reagent’s temperature and the total addition of peroxide (g

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Analysis of Plasma-activated Medium (PAM) in aqueous solution by an Atmospheric Pressure Plasma Jet (APPJ)

MATEC Web of Conferences ◽

10.1051/matecconf/201819702013 ◽

2018 ◽

Vol 197 ◽

pp. 02013 ◽

Cited By ~ 1

Author(s):

Andi Wibowo Kinandana ◽

Sumariyah Sumariyah ◽

Muhammad Nur

Keyword(s):

Hydrogen Peroxide ◽

Species Composition ◽

Exposure Time ◽

Atmospheric Pressure ◽

Atmospheric Pressure Plasma ◽

Plasma Jet ◽

Reactive Species ◽

Atmospheric Pressure Plasma Jet ◽

Liquid Media ◽

Pressure Plasma

Plasma-activated medium (PAM) has been produced by exposing a liquid media to Argon plasma jet. The jet plasma exposure to liquid media has produced reactive Oxygen species (ROS) in liquid phase. This study aims to determine the number of reactive species in plasma-activated medium. An atmospheric pressure plasma jet (APPJ) was generated with a dielectric barrier discharge (DBD) column by AC high voltage. Some parameters varied including exposure time; i.e. 5, 10, 15, 20, 25, and 30 min; and the distance between reactor and active media; i.e. 1, 2 and 3 cm. Some analysis conducted including variation of exposure times, the distances of reactor to PAM which affect produced concentration, and the reactive species composition in plasma-activated medium. In addition, temperature characteristics, pH levels, dissolved ozone and dissolved hydrogen peroxide concentrations were also observed in this study. The results showed that increased exposure time resulted in decreased pH, increased temperature and increased concentrations of ozone and hydrogen peroxide. The maximum reactive species composition was obtained at the distance between reactor and plasma-activated medium of 2 cm. Maximum reactive species composition obtained in this study has temperature of 29-30 Celsius degrees; pH 3.5; dissolved ozone 2.97 ppm; and Hydrogen Peroxide 215 ppm.

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