Removal of ZnO nanoparticles in simulated wastewater treatment processes and its effects on COD and NH4+-N reduction

2013 ◽  
Vol 67 (2) ◽  
pp. 254-260 ◽  
Author(s):  
Linlin Hou ◽  
Jing Xia ◽  
Kaiyang Li ◽  
Jian Chen ◽  
Xiaolei Wu ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Zno Nanoparticles ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Engineered Nanoparticles ◽  
Zno Nps ◽  
Treatment Processes ◽  
N Removal ◽  
Simulated Wastewater ◽  
High Concentrations

For many engineered nanoparticles, the primary pathway of release into the environment is via sewage and industrial wastewater discharges. In this work, the removal of uncoated ZnO nanoparticles (ZnO NPs) during simulated wastewater treatment processes and its impact on treatment performance were examined. Simulated primary clarification removed the majority (about 70%) of the dosed ZnO NPs. During simulated sequencing batch reactor (SBR) processes, ZnO NPs were completely removed in each cycle throughout the 11-day experimental duration (two cycles per day). Continuous input of ZnO NPs into the wastewater (at concentrations up to 5 mg L−1) did not reduce chemical oxygen demand (COD) removal. NH4+-N removal was reduced at a dosing concentration of 5 mg L−1 ZnO NPs per cycle. Inhibition of respiration of nitrifying microorganisms by ZnO NPs corroborated the reduction of NH4+-N removal. These results indicate that if the wastewater is treated, the release of ZnO NPs into receiving water bodies would be minimal and ZnO NPs would mainly accumulate in biosolids. Uncoated ZnO NPs in wastewater at very high concentrations may have some adverse effects on activated sludge process.

Microbiote shift in sequencing batch reactors in response to antimicrobial ZnO nanoparticles

RSC Advances ◽  
2016 ◽  
Vol 6 (111) ◽  
pp. 110108-110111 ◽  
Author(s):  
Zhenghui Liu ◽  
Huifang Zhou ◽  
Jiefeng Liu ◽  
Xudong Yin ◽  
Yufeng Mao ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Wastewater Treatment ◽  
Adverse Effects ◽  
Zno Nanoparticles ◽  
Zinc Oxide Nanoparticles ◽  
Wastewater Treatment Plants ◽  
Oxide Nanoparticles ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Zno Nps

Zinc oxide nanoparticles (ZnO NPs) have been monitored in wastewater treatment plants as their potential adverse effects on functional microorganisms have been causing increasing concern.

Incorporating sulfur reactions and interactions with iron and phosphorus into a general plant-wide model

2018 ◽  
Vol 79 (1) ◽  
pp. 26-34 ◽  
Author(s):  
Hélène Hauduc ◽  
Tanush Wadhawan ◽  
Bruce Johnson ◽  
Charles Bott ◽  
Matthew Ward ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Optimization Design ◽  
Oxygen Demand ◽  
Phosphorus Release ◽  
Sulfur Cycle ◽  
Precipitate Formation ◽  
Treatment Processes ◽  
Whole Plant ◽  
Plant Process ◽  
P Removal

Abstract Sulfur causes many adverse effects in wastewater treatment and sewer collection systems, such as corrosion, odours, increased oxygen demand, and precipitate formation. Several of these are often controlled by chemical addition, which will impact the subsequent wastewater treatment processes. Furthermore, the iron reactions, resulting from coagulant addition for chemical P removal, interact with the sulfur cycle, particularly in the digester with precipitate formation and phosphorus release. Despite its importance, there is no integrated sulfur and iron model for whole plant process optimization/design that could be readily used in practice. After a detailed literature review of chemical and biokinetic sulfur and iron reactions, a plant-wide model is upgraded with relevant reactions to predict the sulfur cycle and iron cycle in sewer collection systems, wastewater and sludge treatment. The developed model is applied on different case studies.

scholarly journals Short investigation on occurrence and removal of semivolatiles during wastewater treatment processes

2021 ◽  
Vol 3 (2) ◽  
pp. 130-140
Author(s):  
Maria Diana Puiu ◽  
Keyword(s):  
Wastewater Treatment ◽  
Organic Contaminants ◽  
Biological Treatment ◽  
Organic Matter Content ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Matter Content ◽  
Physical Treatment ◽  
Dissolved Air Flotation ◽  
Treatment Processes

The food industry wastewater is known to present a high organic matter content, due to specific raw materials and processing activities. Even if these compounds are not directly toxic to the environment, high concentrations in effluents could represent a source of pollution as discharges of high biological oxygen demand may impact receiving river's ecosystems. Identifying the main organic contaminants in wastewater samples represents the first step in establishing the optimum treatment method. The sample analysis for the non-target compounds through the GC-MS technique highlights, along with other analytical parameters, the efficiency of the main physical and biological treatment steps of the middle-size Wastewater Treatment Plant (WWTP). Long-chain fatty acids and their esters were the main abundant classes of non-target identified compounds. The highest intensity detection signal was reached by n-hexadecanoic acid or palmitic acid, a component of palm oil, after the physical treatment processes with dissolved air flotation, and by 1-octadecanol after biological treatment.

scholarly journals Occurrence and Removal of Veterinary Antibiotics in Livestock Wastewater Treatment Plants, South Korea

Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 720 ◽  
Author(s):  
Jin-Pil Kim ◽  
Dal Rae Jin ◽  
Wonseok Lee ◽  
Minhee Chae ◽  
Junwon Park
Keyword(s):  
Wastewater Treatment ◽  
South Korea ◽  
Removal Efficiency ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Veterinary Antibiotics ◽  
Livestock Wastewater ◽  
Treatment Processes ◽  
Removal Efficiencies ◽  
A2o Process

In this study, livestock wastewater treatment plants in South Korea were monitored to determine the characteristics of influent and effluent wastewater, containing four types of veterinary antibiotics (sulfamethazine, sulfathiazole, chlortetracycline, oxytetracycline), and the removal efficiencies of different treatment processes. Chlortetracycline had the highest average influent concentration (483.7 μg/L), followed by sulfamethazine (251.2 μg/L), sulfathiazole (230.8 μg/L) and oxytetracycline (25.7 μg/L), at five livestock wastewater treatment plants. Sulfathiazole had the highest average effluent concentration (28.2 μg/L), followed by sulfamethazine (20.8 μg/L) and chlortetracycline (11.5 μg/L), while no oxytetracycline was detected. For veterinary antibiotics in the wastewater, a removal efficiency of at least 90% was observed with five types of treatment processes, including a bio-ceramic sequencing batch reactor, liquid-phase flotation, membrane bioreactor, bioreactor plus ultrafiltration (BIOSUF) and bio best bacillus systems. Moreover, this study evaluated the removal efficiency via laboratory-scale experiments on the conventional contaminants, such as organic matter, nitrogen, phosphorus and veterinary antibiotics. This was done using the hydraulic retention time (HRT), under three temporal conditions (14 h, 18 h, 27 h), using the anaerobic–anoxic–oxic (A2O) process, in an attempt to assess the combined livestock wastewater treatment process where the livestock wastewater is treated until certain levels of water quality are achieved, and then the effluent is discharged to nearby sewage treatment plants for further treatment. The removal efficiencies of veterinary antibiotics, especially oxytetracycline and chlortetracycline, were 86.5–88.8% and 87.9–90.8%, respectively, exhibiting no significant differences under various HRT conditions. The removal efficiency of sulfamethazine was at least 20% higher at HRT = 27 h than at HRT = 14 h, indicating that sulfamethazine was efficiently removed in the A2O process with increased HRT. This study is expected to promote a comprehensive understanding of the behavior and removal of veterinary antibiotics in the livestock wastewater treatment plants of South Korea.

Removal of pharmaceutical residue in municipal wastewater by DAF (dissolved air flotation)–MBR (membrane bioreactor) and ozone oxidation

2012 ◽  
Vol 66 (12) ◽  
pp. 2546-2555 ◽  
Author(s):  
Miyoung Choi ◽  
Dong Whan Choi ◽  
Jung Yeol Lee ◽  
Young Suk Kim ◽  
Bun Su Kim ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Membrane Bioreactor ◽  
Municipal Wastewater ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Ozone Oxidation ◽  
Dissolved Air Flotation ◽  
Treatment Processes ◽  
Pharmaceutical Residue ◽  
Dissolved Air

Growing attention is given to pharmaceutical residue in the water environment. It is known that pharmaceuticals are able to survive from a series of wastewater treatment processes. Concerns regarding pharmaceutical residues are attributed to the fact that they are being detected in water and sediment environment ubiquitously. Pharmaceutical treatment using a series of wastewater treatment processes of the DAF (dissolved air flotation)–MBR (membrane bioreactor)–ozone oxidation was conducted in the study. DAF, without addition of coagulant, could remove CODcr (chemical oxygen demand by Cr) up to over 70%, BOD 73%, SS 83%, T-N 55%, NH4+ 23%, and T-P 65% in influent of municipal wastewater. Average removal rates of water quality parameters by the DAF–MBR system were very high, e.g. CODcr 95.88%, BOD5 99.66%, CODmn (chemical oxygen demand by Mn) 93.63%, T-N 69.75%, NH4-N 98.46%, T-P 78.23%, and SS 99.51%, which satisfy effluent water quality standards. Despite the high removal rate of the wastewater treatment system, pharmaceuticals were eliminated to be about 50–99% by the MBR system, depending on specific pharmaceuticals. Ibuprofen was well removed by MBR system up to over 95%, while removal rate of bezafibrate ranged between 50 and 90%. With over 5 mg/l of ozone oxidation, most pharmaceuticals which survived the DAF–MBR process were removed completely or resulted in very low survival rate within the range of few micrograms per litre. However, some pharmaceuticals such as bezafibrate and naproxen tended to be resistant to ozone oxidation.

Optimization of leachate treatment using persulfate/H2O2 based advanced oxidation process: case study: Deir El-Balah Landfill Site, Gaza Strip, Palestine

2015 ◽  
Vol 73 (1) ◽  
pp. 102-112 ◽  
Author(s):  
Ahmed H. Hilles ◽  
Salem S. Abu Amr ◽  
Rim A. Hussein ◽  
Anwar I. Arafa ◽  
Olfat D. El-Sebaie
Keyword(s):  
Reaction Time ◽  
Advanced Oxidation Process ◽  
Gaza Strip ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Leachate Treatment ◽  
Operating Variables ◽  
Treatment Processes ◽  
N Removal

The objective of this study was to investigate the performance of employing H2O2 reagent in persulfate activation to treat stabilized landfill leachate. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as persulfate and H2O2 dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following two responses proved to be significant with very low probabilities (<0.0001): chemical oxygen demand (COD) and NH3-N removal. The obtained optimum conditions included a reaction time of 116 min, 4.97 g S2O82−, 7.29 g H2O2 dosage and pH 11. The experimental results were corresponding well with predicted models (COD and NH3-N removal rates of 81% and 83%, respectively). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as persulfate only and H2O2 only, to evaluate its effectiveness. The combined method (i.e., /S2O82−/H2O2) achieved higher removal efficiencies for COD and NH3-N compared with other studied applications.

Applicability of an electrochemical Fenton-type process to actual wastewater treatment

2015 ◽  
Vol 72 (6) ◽  
pp. 850-857 ◽  
Author(s):  
Naoyuki Kishimoto ◽  
Takuya Kitamura ◽  
Yu Nakamura
Keyword(s):  
Wastewater Treatment ◽  
Chemical Oxygen Demand ◽  
Municipal Wastewater ◽  
Oxygen Demand ◽  
Metal Scrap ◽  
Yellow Colour ◽  
Type Process ◽  
Automobile Factory ◽  
High Concentrations ◽  
Electrochemical Fenton

The applicability of an electrochemical Fenton-type process (EF-HOCl-ReFe) to the treatment of three actual wastewaters, namely wastewater from an automobile factory (automobile wastewater), metal scrap-cleansing wastewater, and municipal wastewater, is discussed in this research. The EF-HOCl-ReFe successfully removed the chemical oxygen demand (COD) from automobile wastewater pre-treated by a coagulation process without any inhibition. The apparent current efficiency reached 86%, 46% of which was ascribed to the electrochemical Fenton-type mechanism. The metal scrap-cleansing wastewater had a yellow colour and high concentrations of COD (6550 mg/L) and Cl− (1560 mM). The EF-HOCl-ReFe could achieve almost complete COD removal and decolourization after 48 h of treatment, although a temporary intensification of colour was observed before the decolourization. The EF-HOCl-ReFe was also effective in the removal of 1,4-dioxane from municipal wastewater pre-treated by activated sludge and coagulation processes, which were unable to remove 1,4-dioxane. The 1,4-dioxane removal efficiency after 30 min of treatment reached 68.5%. Thus, the EF-HOCl-ReFe was applicable to the treatment of these actual wastewaters.

scholarly journals Swine wastewater treatment by combined process of iron carbon microelectrolysis-physical adsorption-microalgae cultivation

2021 ◽  
Author(s):  
Wenjin Zhang ◽  
Rongbin Xia ◽  
Hao Wang ◽  
Shihua Pu ◽  
Dongmei Jiang ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Physical Adsorption ◽  
Oxygen Demand ◽  
Dry Weight ◽  
Swine Wastewater ◽  
Combined Treatments ◽  
Microalgae Cultivation ◽  
Integrated Method ◽  
N Removal ◽  
Maximum Cell

Abstract Combined treatments were designed based on iron-carbon micro-electrolysis treatment (ICME), physical adsorption (PA) with zeolite (Z) or vermiculite (V) and microalgae cultivation (MC, C. vulgaris) for removing pollutants from swine wastewater (SW), herein are ICME + MC (IM), ICME + Z + MC (IZM) and ICME + V + MC (IVM). Results showed that the minimum total nitrogen (TN) of 43.66 mg L−1, NH4+-N of 1.33 mg−1 and total phosphorus (TP) of 0.14 mg−1 were obtained by IVM, while the minimum chemical oxygen demand (COD) was 105 mg−1 via IM. During the process of combined treatments, ICME contributed most to the removal of TN (84.52% by IZM), TP (97.78% by IVM and IZM) and COD (62.44% by IVM), and maximum NH4+-N removal (55.64%) was obtained by MC procedure in IM process. Vermiculite performed better than zeolite during all the combined treatments. Besides, the maximum cell dry weight (CDW, 0.74 g−1) of C. vulgaris was obtained by IM on day 13. The results provide an efficient integrated method for swine wastewater treatment.

scholarly journals Development of a cost-effective wastewater treatment process: combination of different process

2021 ◽  
Vol 233 ◽  
pp. 01106
Author(s):  
Song Du ◽  
Wenbiao Jin
Keyword(s):  
Wastewater Treatment ◽  
Catalytic Oxidation ◽  
Treatment Process ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Cost Effective ◽  
Fenton Oxidation ◽  
Wastewater Treatment Process ◽  
Combination Process ◽  
Electro Catalytic Oxidation

Caprolactam wastewater produced by the production process of caprolactam is characterized by a very high toxicity and chemical oxygen demand (COD) values, having potential harm to the environment if treated improperly. However, these characteristics make caprolactam wastewaters difficult to treat using traditional methods. So the aim of this work was to develop a cost-effective caprolactam wastewater treatment process. Fenton oxidation, sequencing batch reactor activated sludge process (SBR) and electro-catalytic oxidation were proposed to treat caprolactam wastewater in the laboratory scale, and the treatment effects were investigated. Compared with Fenton oxidation, SBR and electro-catalytic oxidation can treat caprolactam wastewater at a lower cost and more efficiently. The pilot test results indicate that the COD can be decreased to less than 1000 mg/L by the combination process, and when the COD removal rates maintain 90%, the cost of caprolactam wastewater treatment is below 6 yuan/m3. The combination process showed better economic benefit.

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