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Nascimento BZ, Muniz EP, Bueno Cotta AJ, Couto Oliveira FD, Sérgio da Silva Porto P. Oily wastewater treatment by a continuous flow electrocoagulation reactor with polarity switch: Assessment of the relation between process variables and the aluminum released to the environment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119072. [PMID: 37774662 DOI: 10.1016/j.jenvman.2023.119072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/23/2023] [Accepted: 08/30/2023] [Indexed: 10/01/2023]
Abstract
Electrocoagulation with electrical polarity inversion was used to treat oil in water emulsions (145 ± 5 mg dm-3) using a cylindrical 4.8 dm3 reactor in continuous mode. The effects of spatial time and time between polarity inversion were explored using a three-level full factorial design (32), followed by Spearman correlation (ps), which has shown that the aluminum concentration in the treated effluent is not directly dependent on the mass of aluminum released by the electrodes. Nonetheless, the loss of mass of the electrodes is correlated (ps = 0.6970) to oil removal and to less electric power consumption (ps = -0.6909). Surface response analysis revealed that increasing the number of inversion cycles reduces electrode degradation. The treatment reduced the effluent's chemical oxygen demand by over 92.8%. Regarding environmental impact, there is an inverse statistical correlation between aluminum in the treated effluent and oil removal (ps = -0.7426), indicating that removing more oil with less environmental impact is possible. The better condition, considering oil removal and lower electrode consumption, was obtained with a spatial time of 36 min and a polarity inversion time of 10 s; for this condition, oil removal reached 87.0% with an energy expenditure of about 7.21 kW h.m-3.
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Affiliation(s)
- Bárbara Zon Nascimento
- Programa de Pós-graduação Em Energia, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil
| | - Eduardo Perini Muniz
- Programa de Pós-graduação Em Energia, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil; Departamento de Ciências Naturais, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil.
| | - Aloisio José Bueno Cotta
- Departamento de Ciências Naturais, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil
| | - Flavio Duarte Couto Oliveira
- Departamento de Computação e Eletrônica, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil
| | - Paulo Sérgio da Silva Porto
- Programa de Pós-graduação Em Energia, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil; Departamento de Engenharias e Tecnologia, Universidade Federal Do Espírito Santo, Rodovia Governador Mario Covas, Km 60, Bairro Litorâneo, CEP 29932-540, São Mateus, ES, Brazil
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Sanei E, Mokhtarani N. Leachate post-treatment by electrocoagulation process: Effect of polarity switching and anode-to-cathode surface area. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115733. [PMID: 35868189 DOI: 10.1016/j.jenvman.2022.115733] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/09/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
In the electrocoagulation process, passivation or corrosion of the electrodes is one of the biggest challenges that cause a drop in treatment effectiveness. In this study, the effect of polarity switching was investigated, for the first time, in an attempt to enhance electrocoagulation treatment's ability to remove chemical oxygen demand (COD) and color from pretreated landfill leachate. Moreover, the ratio of the anode to cathode surface area and rotating electrode were examined in light of experimental results. The effect of different parameters, including the stirring speed, initial leachate pH, electrical current density, anode to cathode surface area ratio, and polarity switching time on system efficiency, was evaluated using the one-factor-at-a-time (OFAT) classical method. According to the results, polarity switching resulted in an almost 18% increase in COD removal, 14% increase in color removal, 13% decrease in electrical energy consumption (EEC), 51% decrease in the specific sludge production (TSS/COD), and improved electrode performance compared to non-polarity switching mode. The findings of this research showed the highest COD and color removal efficiencies, which were 34% and 67%, respectively, in a 120 min period, a stirring speed of 135 rpm, the initial leachate pH of 9, the current density of 14.4 mA/cm2, the anode/cathode surface ratio of 0.35, and the polarity switching time of 300 s.
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Affiliation(s)
- Emad Sanei
- Civil and Environmental Engineering Faculty, Tarbiat Modares University, Tehran, 1411713116, Iran; Earth and Ecosystem Science Faculty, Central Michigan University, Mt Pleasant, 48859, Michigan, USA
| | - Nader Mokhtarani
- Civil and Environmental Engineering Faculty, Tarbiat Modares University, Tehran, 1411713116, Iran.
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3
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Posavcic H, Halkijevic I, Vouk D, Druskovic M. Application of Box-Behnken design for circulating flow sono-electrocoagulation for oily wastewater treatment. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2022; 57:645-655. [PMID: 35838490 DOI: 10.1080/10934529.2022.2099520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
The increasing production of oily wastewater as a by-product of industry has become a major environmental problem. Therefore, this article investigates the removal of mineral oil from oily wastewater by a circulating flow sono-electrocoagulation. The Box-Behnken design was used to study the effects of characteristic electrocoagulation and ultrasonic parameters on mineral oil removal efficiency. A total of 34 different experimental setups were performed at a laboratory scale. A reduced cubic regression model with derived coefficients was developed to describe the mineral oil removal rate. The experimental results show that circulating flow sono-electrocoagulation with iron electrodes can effectively reduce mineral oil by 93.3% under the optimum conditions of 10.948 cycles, a current density of 107.12 A m-2 and a flow rate of 0.468 L s-1. The experimental observations agreed well with the modeled values, and the model was verified experimentally. Under the optimal conditions, the average operating cost was 0.77 EUR/m3.
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Affiliation(s)
- Hana Posavcic
- Water Research Department, Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
| | - Ivan Halkijevic
- Water Research Department, Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
| | - Drazen Vouk
- Water Research Department, Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
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Abstract
The growing interest in innovations regarding the treatment of oily wastewater stems from the fact that the oil industry is the largest polluter of the environment. The harm caused by this industry is seen in all countries. Companies that produce such wastewater are responsible for its treatment prior to disposal or recycling into their production processes. As oil emulsions are difficult to manage and require different types of treatment or even combined methods, a range of environmental technologies have been proposed for oil-contaminated effluents, such as gravity separation, flotation, flocculation, biological treatment, advanced oxidation processes, and membranes. Natural materials, such as biopolymers, constitute a novel, sustainable solution with considerable potential for oily effluent separation. The present review offers an overview of the treatment of oily wastewater, describing current trends and the latest applications. This review also points to further research needs and major concerns, especially with regards to sustainability, and discusses potential biotechnological applications.
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Shonza NS, Andreatta D, Muniz EP, Dalmaschio CJ, de Freitas RR, Porto PSDS. Crude oil wastewater treatment by electrocoagulation in a continuous process with polarity switch. ENVIRONMENTAL TECHNOLOGY 2022; 43:1700-1708. [PMID: 33151813 DOI: 10.1080/09593330.2020.1847205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 10/23/2020] [Indexed: 06/11/2023]
Abstract
The influence of the distance between electrodes, electrical current, and flow rate of emulsified crude oil in water effluent through an electrocoagulation reactor was studied. Power switch at an interval of 30 s was used to reduce electrode passivation. The output variables were power consumption, pH, and oil removal from effluent. There was no significant change in the output variables with the working time of the reactor. The final pH was between 7.5 and 9.5 depending on the input variables. It increases with higher electrical current and tends to decrease with increased flow rate. Increasing electrical current tends to increase while increasing either distance between electrodes or the flow rate tends to reduce oil removal. Using a 2.88 L reactor, it is possible to treat 7.12 L of effluent in one hour, removing 78% of the crude oil, keeping final pH at 8.3, and this system will have an energy consumption of 21.6 kWh.
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Affiliation(s)
- Nasibu Samson Shonza
- Programa de Pós-graduação em Energia, Universidade Federal do Espírito Santo, São Mateus, Brasil
| | - Domênico Andreatta
- Programa de Pós-graduação em Energia, Universidade Federal do Espírito Santo, São Mateus, Brasil
| | - Eduardo Perini Muniz
- Programa de Pós-graduação em Energia, Universidade Federal do Espírito Santo, São Mateus, Brasil
- Departamento de Ciências Naturais, Universidade Federal do Espírito Santo, São Mateus, Brasil
| | | | - Rodrigo Randow de Freitas
- Programa de Pós-graduação em Energia, Universidade Federal do Espírito Santo, São Mateus, Brasil
- Departamento de Engenharias e Tecnologia, Universidade Federal do Espírito Santo, São Mateus, Brasil
| | - Paulo Sérgio da Silva Porto
- Programa de Pós-graduação em Energia, Universidade Federal do Espírito Santo, São Mateus, Brasil
- Departamento de Engenharias e Tecnologia, Universidade Federal do Espírito Santo, São Mateus, Brasil
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Druskovic M, Vouk D, Posavcic H, Halkijevic I, Nad K. The application of electrochemical processes in oily wastewater treatment: a review. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2021; 56:1373-1386. [PMID: 34783645 DOI: 10.1080/10934529.2021.1999714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
Oily wastewater is becoming a concern worldwide due to its quantities and the presence of contaminants and its sustainable treatment should be cost-effective and meet all requirements so the contaminants are not transferred to the environment. The paper reviews the state-of-the-art in the oily wastewater treatment by electrochemical processes such as electrochemical advanced oxidation processes and electrocoagulation. Efficiency of oily wastewater treatment has been thoroughly investigated with its expression as a function of the main technological (process) parameters. Fe and Al electrodes, as well as their combination have proven to be very effective in oily wastewater treatment with slightly better performance of Al electrodes. Higher current densities and longer reaction times result with higher COD, TOC, turbidity, phenol and oil and grease removal efficiencies, but with resulting increase in wastewater temperature and energy consumption, so there is a strong need for the process optimization. There is a need for further research on the treatment efficiencies of different contaminants (heavy metals, total hydrocarbons, organic halogens, cyanides, etc.). A lack of research is presented on the treatment efficiency with electrodes of different materials as well as the analyses of the sludge production and its further treatment and use or disposal.
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Affiliation(s)
| | - Drazen Vouk
- Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
| | - Hana Posavcic
- Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
| | - Ivan Halkijevic
- Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
| | - Karlo Nad
- Rudjer Boskovic Institute, Zagreb, Croatia
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Lu J, Zhang P, Li J. Electrocoagulation technology for water purification: An update review on reactor design and some newly concerned pollutants removal. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113259. [PMID: 34256295 DOI: 10.1016/j.jenvman.2021.113259] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/30/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Water shortage and quality deterioration are plaguing people all over the world. Providing sustainable and affordable treatment solutions to these problems is a need of the hour. Electrocoagulation (EC) technology is a burgeoning alternative for effective water treatment, which offers the virtues such as compact equipment, easy operation, and low sludge production. Compared to other water purification technologies, EC shows excellent removal efficacy for a wide range of contaminants in water and has great potential for addressing limitations of conventional water purification technologies. This review summarizes the latest development of principle, characteristics, and reactor design of EC. The design of key parameters including reactor shape, power supply type, current density, as well as electrode configuration is further elaborated. In particular, typical water treatment systems powered by renewable energy (solar photovoltaic and wind turbine systems) are proposed. Further, this review provides an overview on expanded application of EC in the removal of some newly concerned pollutants in recent years, including arsenite, perfluorinated compounds, pharmaceuticals, oil, bacteria, and viruses. The removal efficiency and mechanisms of these pollutants are also discussed. Finally, future research trend and focus are further recommended. This review can bridge the large knowledge gap for the EC application that is beneficial for environmental researchers and engineers.
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Affiliation(s)
- Jianbo Lu
- School of Civil Engineering, Yantai University, Yantai, Shandong, 264005, China.
| | - Peng Zhang
- School of Civil Engineering, Yantai University, Yantai, Shandong, 264005, China
| | - Jie Li
- School of Economics and Management, Yantai University, Yantai, Shandong, 264005, China
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Elmobarak WF, Almomani F. Functionalization of silica-coated magnetic nanoparticles as powerful demulsifier to recover oil from oil-in-water emulsion. CHEMOSPHERE 2021; 279:130360. [PMID: 33862358 DOI: 10.1016/j.chemosphere.2021.130360] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 03/02/2021] [Accepted: 03/20/2021] [Indexed: 06/12/2023]
Abstract
This study presents an innovative approach for the preparation of Fe3O4 nanoparticles covered with SiO2 shell (denoted as Fe-Si-MNP), which were used to recover oil recovery from oil-in-water emulsion (O/W-emul). The Fe-Si-MNP were prepared with differing silica layer thicknesses (5 nm [Fe-Si-1], 8 nm [Fe-Si-2], 10 nm [Fe-Si-3], and 15 nm [Fe-Si-4]) and tested for the percentage of oil separation (%Soil) under different dosages (DMNP), oil concentration (Doil), surfactant dosages (Dsur), and pH. The Fe-Si-MNP exhibited excellent %Soil, reliable stability, and high magnetization values ranging between 46.1 and 80.2 emu/g. adding a 5 nm silica layer on the surface of the Fe-Si-MNP (i.e., Fe-Si-1) protected them from oxidation conditions, extended their service life, and achieved a %Soil of ∼96.3%. The %Soil slightly decreased to ∼92% with an alkaline pH or when the thickness of the silica layer increased to ≥10 nm. The %Soil was 90.5%, 89.5%, and 87.5% for Fe-Si-2, Fe-Si-3, and Fe-Si-4, respectively. Increasing the water salinity from 0.1 to 0.5 M slightly improved the %Soil for the tests carried out with a Doil of 100 mg/L to 93.3%, 90.3%, and 86.3% for Fe-Si-2, Fe-Si-3, and FeSi-4, respectively. The highest %Soil achieved with Fe- Si-1 Fe-Si-2 and Fe-Si-3 was >95%, 95% and 92%, respectively. The Fe-Si-MNP exhibited a high recyclability for 9 cycles with the lowest %Soil ∼80%. The results suggest that the structure and properties of the Fe-Si-MNP can be manipulated to achieve a high oil recovery, easy separation, and extended service life.
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Affiliation(s)
| | - Fares Almomani
- Department of Chemical Engineering, Qatar University, P. O. Box 2713, Doha, Qatar.
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Elmobarak WF, Almomani F. Application of Fe 3O 4 magnetite nanoparticles grafted in silica (SiO 2) for oil recovery from oil in water emulsions. CHEMOSPHERE 2021; 265:129054. [PMID: 33280845 DOI: 10.1016/j.chemosphere.2020.129054] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/10/2020] [Accepted: 11/17/2020] [Indexed: 05/13/2023]
Abstract
In this study, an innovative magnetic demulsifier (MD) was prepared by grafting a silica layer onto the surface of the Fe3O4 magnetic nanoparticles (MNPs) using the modified Stober process. The MD was characterized using various analytical techniques (XRD, FTIR, TGA, TEM, VSM, etc.) and employed to recover oil from O/W emulsion, which were then regenerated and recycled several times. The effects of magnetic demulsifier dosage (MDdose), the concentration of oil (Coil), pH, the concentration of the surfactant (Csur), and separation time (tsep) on the demulsification efficiency (%ηdem), and the percentage of oil recovered (%Roil) were evaluated. An excellent %ηdem ≥ 90% was achieved Coil in the range 50-2000 mg/L. Using an MDdose as low as 10 mg/L attained a %ηdem in the range of 93%-94.3% for O/W mixtures with Coil < 2000 mg/L, which slightly decreased to ∼90% for higher concentrations. The reported %Roil (p-value <0.05) was >90 ± 0.1 for tests carried out with pH ≤ 7 and Csur ≤ 0.1 g/L and declined at higher pH and Csur to % 86.5 due to the increase in emulsion stability. The developed MD exhibited high recyclability at an effective and stable %Roil and %ηdem of ∼90% and 86.4% after 9 cycles, respectively. Demulsification process best fits the combined Langmuir-Freundlich (L-F) isotherm with highest adsorption capacity (Qmax) of 186.0 ± 5 mgoil/gMD compared to 86.0 ± 5 mgoil/gMD for Fe3O4, which is 1.1 folds greater than Qmax reported in the literature for other demulsifiers.
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Affiliation(s)
| | - Fares Almomani
- Department of Chemical Engineering, Qatar University, P. O. Box 2713, Doha, Qatar.
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Woo S, Cho H, Park J, Shin Y, Hwang W. A novel approach to designing a biomimetic wettable patterned surface for highly efficient and continuous surfactant-free oil emulsion separation. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116864] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Xiong Y, Huang X, Lu B, Wu B, Lu L, Liu J, Peng K. Acceleration of floc-water separation and floc reduction with magnetic nanoparticles during demulsification of complex waste cutting emulsions. J Environ Sci (China) 2020; 89:80-89. [PMID: 31892403 DOI: 10.1016/j.jes.2019.10.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 06/10/2023]
Abstract
Waste cutting emulsions are difficult to treat efficiently owing to their complex composition and stable emulsified structure. As an important treatment method for emulsions, chemical demulsification is faced with challenges such as low flocs-water separation rates and high sludge production. Hence, in this study, Fe3O4 magnetic nanoparticles (MNPs) were used to enhance chemical demulsification performance for treating waste cutting emulsions under a magnetic field. The addition of MNPs significantly decreased the time required to attain sludge-water separation and sludge compression equilibrium, from 210 to 20 min. In addition, the volume percentage of sludge produced at the equilibrium state was reduced from 45% to 10%. This excellent flocculation-separation performance was stable over a pH range of 3-11. The magnetization of the flocculants and oil droplets to form a flocculant-MNP-oil droplet composite, and the magnetic transfer of the composite were two key processes that enhanced the separation of cutting emulsions. Specifically, the interactions among MNPs, flocculants, and oil droplets were important in the magnetization process, which was controlled by the structures and properties of the three components. Under the magnetic field, the magnetized flocculant-MNP-oil droplet composites were considerably accelerated and separated from water, and the sludge was simultaneously compressed. Thus, this study expands the applicability of magnetic separation techniques in the treatment of complex waste cutting emulsions.
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Affiliation(s)
- Yongjiao Xiong
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Xiangfeng Huang
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Bin Lu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Baoqiang Wu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Lijun Lu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Jia Liu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China
| | - Kaiming Peng
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China.
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Priya M, Jeyanthi J. Removal of COD, oil and grease from automobile wash water effluent using electrocoagulation technique. Microchem J 2019. [DOI: 10.1016/j.microc.2019.104070] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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13
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Facile development of poly(tetrafluoride ethylene-r-vinylpyrrolidone) modified PVDF membrane with comprehensive antifouling property for highly-efficient challenging oil-in-water emulsions separation. J Memb Sci 2019. [DOI: 10.1016/j.memsci.2019.04.071] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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14
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Optimization of an integrated electrocoagulation/sedimentation unit for purification of polymer-flooding sewage. J Electroanal Chem (Lausanne) 2019. [DOI: 10.1016/j.jelechem.2019.04.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Jiang WM, Chen YM, Chen MC, Liu XL, Liu Y, Wang T, Yang J. Removal of emulsified oil from polymer-flooding sewage by an integrated apparatus including EC and separation process. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.09.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Genc A, Goc S. Electroflotation of oily wastewater using stainless steel sponge electrodes. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 78:1481-1488. [PMID: 30427788 DOI: 10.2166/wst.2018.422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this study, emulsified oil removals have been studied electrochemically by using stainless steel sponge electrode beds. A first-order electroflotation model was developed and the model estimation were consistent with the experimental results. It was found out that the mean electroflotation rate constant was mainly a function of the voltage applied to the electrode beds. In addition, the properties of intermediate materials (electrical conductivity) placed between the anode and cathode electrode beds strongly affected removal yields. For the initial concentration of 57,150 mg/L, the chemical oxygen demand (COD) removal was obtained as 85% under the conditions of voltage gradient 15 V. The experiments were also performed by varying the electrode bed lengths. Even though higher oil yields were obtained at 27 cm bed length, similar oil yields were also obtained at 18 cm bed length, especially after 60 min, with less energy consumption. Therefore, the optimum electrode bed length was concluded to be 18 cm.
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Affiliation(s)
- A Genc
- Department of Environmental Engineering, Bulent Ecevit University, 67100 Zonguldak, Turkey E-mail:
| | - S Goc
- Department of Environmental Engineering, Bulent Ecevit University, 67100 Zonguldak, Turkey E-mail:
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Liu Y, Yang J, Jiang W, Chen Y, Yang C, Wang T, Li Y. Experimental studies on the enhanced performance of lightweight oil recovery using a combined electrocoagulation and magnetic field processes. CHEMOSPHERE 2018; 205:601-609. [PMID: 29715674 DOI: 10.1016/j.chemosphere.2018.04.113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
On marine oil spill, inflammable lightweight oil has characteristics of explosion risk and contamination of marine enviroment, therefore treatment of stable emulsion with micron oil droplets is urgent. This study aimed to propose a combined electrocoagulation and magnetic field processes to enhance performance of lightweight oil recovery with lower energy consumption. The effects of current density, electrolysis time, strength and direction of magnetic field on the overall treatment efficiency of the reactor were explored. Furthermore, the comparison between coupling device and only electrocoagulation through tracking oil removal in nine regions between the electrodes. The results were shown that the permanent magnets applied was found to enhance demulsification process within electrocoagulation reactor. For a given current density of 60 A m-2 at 16 min, Lorentz force downward was proved to promote the sedimentation of coagulants. As the magnetic field strength increases from 20 to 60 mT, oil removal efficiency was observed to increase and then decrease, and simultaneously energy consumption reduced and then present constantly. The results were found that the magnetic field strength of 40 mT was optimal within electrocoagulation reactor, which can not only diminishe difference of mass transfer rate along the height of vertical plate but also consume lowest energy.
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Affiliation(s)
- Yang Liu
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Jie Yang
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Wenming Jiang
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Yimei Chen
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Chaojiang Yang
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Tianyu Wang
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
| | - Yuxing Li
- College of Pipeline and Civil Engineering, Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, China University of Petroleum, Qingdao, Shandong, China.
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Tanyol M, Ogedey A, Oguz E. COD removal from leachate by electrocoagulation process: treatment with monopolar electrodes in parallel connection. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 77:177-186. [PMID: 29339616 DOI: 10.2166/wst.2017.528] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This study examines the removal of chemical oxygen demand (COD) from landfill leachate generated from the municipal landfill site of Bingol, Turkey. The effect of parameters such as current density, pH, and inter-electrode distance during the electrocoagulation (EC) process on COD removal of the process was investigated. Moreover, for COD removal, the energy consumption and operating costs were calculated for iron electrode under the EC conditions. COD removal efficiency was 72.13% at the current density of 16 mA m-2, pH of 8.05, and the inter-electrode distance of 9 mm at the detention time of 60 min with iron electrode and the COD concentration was reduced from 6,100 mg L-1 to 1,700 mg L-1 by EC. The highest value of the electrical energy and electrode consumptions per kg of COD in the optimum conditions were determined as 0.055 kWh kg-1 COD and 3.43 kg kg-1 COD and the highest operating cost value was found to be 1.41 US$ kg-1 COD for 0-60 min time intervals.
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Affiliation(s)
- Mehtap Tanyol
- Department of Environmental Engineering, Munzur University, Tunceli, Turkey
| | - Aysenur Ogedey
- Department of Environmental Engineering, Munzur University, Tunceli, Turkey
| | - Ensar Oguz
- Department of Environmental Engineering, Ataturk University, Erzurum, Turkey E-mail:
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19
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Separation of emulsified crude oil in saline water by dissolved air flotation with micro and nanobubbles. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.06.007] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Jiang W, Chen M, Yang J, Deng Z, Liu Y, Bian J, Du S, Hou D. Dynamic experimental study of a new electrocoagulation apparatus with settlement scheme for the removal process in oilfield. J Electroanal Chem (Lausanne) 2017. [DOI: 10.1016/j.jelechem.2017.07.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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21
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Liu Y, Jiang WM, Yang J, Li YX, Chen MC, Li JN. Experimental study on evaluation and optimization of tilt angle of parallel-plate electrodes using electrocoagulation device for oily water demulsification. CHEMOSPHERE 2017; 181:142-149. [PMID: 28437739 DOI: 10.1016/j.chemosphere.2017.03.141] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/22/2017] [Accepted: 03/25/2017] [Indexed: 06/07/2023]
Abstract
Tilt angle of parallel-plate electrodes (APE) is very important as it improves the economy of diffusion controlled Electrocoagulation (EC) processes. This study aimed to evaluate and optimize APE of a self-made EC device including integrally rotary electrodes, at a fixed current density of 120 Am-2. The APEs investigated in this study were selected at 0°, 30°, 45°, 60°, 90°, and a special value (α(d)) which was defined as a special orientation of electrode when the upper end of anode and the lower end of cathode is in a line vertical to the bottom of reactor. Experiments were conducted to determine the optimum APE for demulsification process using four evaluation indexes, as: oil removal efficiency in the center between electrodes; energy consumption and Al consumption, and besides, a novel universal evaluation index named as evenness index of oil removal efficiency employed to fully reflect distribution characteristics of demulsification efficiency. At a given plate spacing of 4 cm, the optimal APE was found to be α(d) because of its potential of enhancing the mass transfer process within whole EC reactor without addition, external mechanical stirring energy, and finally the four evaluation indexed are 97.07%, 0.11 g Al g-1 oil, 2.99 kwhkg-1 oil, 99.97% and 99.97%, respectively.
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Affiliation(s)
- Yang Liu
- Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology, Qingdao 266580, China; College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, China
| | - Wen-Ming Jiang
- Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology, Qingdao 266580, China; College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, China.
| | - Jie Yang
- Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology, Qingdao 266580, China; College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, China
| | - Yu-Xing Li
- Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology, Qingdao 266580, China; College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, China
| | - Ming-Can Chen
- Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety, Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology, Qingdao 266580, China; College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, China
| | - Jian-Na Li
- Thermal Energy Engineering, Xi'an Jiaotong University, Xi'an 710049, China
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22
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Liu Y, Li Y, Jiang W, Chen M, Yang J, Li J. Quantitative analysis on removal path of emulsified oil in the reactor of EC. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.01.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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23
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Genc A, Eryilmaz C. Dependency of removal efficiency on electrode arrangements in the treatment of oily wastewaters by electrocoagulation. SEP SCI TECHNOL 2017. [DOI: 10.1080/01496395.2017.1295997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Lee MJ, Ong CS, Lau WJ, Ng BC, Ismail AF, Lai SO. Degradation of PVDF-based composite membrane and its impacts on membrane intrinsic and separation properties. JOURNAL OF POLYMER ENGINEERING 2016. [DOI: 10.1515/polyeng-2015-0064] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
In this work, an attempt was made to evaluate the effects of ultraviolet (UV) irradiation period on the intrinsic and separation properties of composite membrane composed of organic polyvinylidene fluoride and inorganic titanium dioxide (TiO2) nanoparticles by exposing the membrane to UV-A light for up to 250 h. The changes on membrane structural morphologies and chemical characteristics upon UV exposure were studied by field-emission scanning electron microscope and Fourier transform infrared, respectively. It was observed that some cracks and fractures were formed on the membrane outer surface when it was exposed to 120-h UV light. Further increase in UV irradiation time to 250 h had caused membrane structure to collapse, turning it into powder form. Filtration experiments showed that the permeate flux of irradiated membrane was significantly increased from 10.89 L/m2 h to 21.84 L/m2 h (>100% flux increment) while oil rejection decreased with increasing UV exposure time from 0 h to 120 h. Furthermore, the mechanical strength and thermal stability of irradiated membrane were also reported to decrease with increasing UV exposure time, suggesting the negative impacts of UV light on the membrane overall stability. This research is of particular importance to evaluate the suitability and sustainability of polymeric membrane, which is widely considered as the host for photocatalyts and used for wastewater treatment process under UV irradiation.
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25
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Saththasivam J, Loganathan K, Sarp S. An overview of oil-water separation using gas flotation systems. CHEMOSPHERE 2016; 144:671-680. [PMID: 26408973 DOI: 10.1016/j.chemosphere.2015.08.087] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 08/31/2015] [Indexed: 06/05/2023]
Abstract
Oil concentration levels in municipal waste water effluent streams are stringently regulated in most parts of the world. Apart from municipal waste, stricter oil/grease discharge limits are also enforced in oil and gas sectors as large volumes of produced water is being discharged to open ocean. One of the feasible, practical and established methods to remove oil substances from waste water sources is by gas flotation. In this overview, gas flotation technologies, namely dissolved and induced flotation systems, are discussed. Physico-chemical interaction between oil-water-gas during flotation is also summarized. In addition to a brief review on design advancements in flotation systems, enhancement of flotation efficiency by using pre-treatment methods, particularly coagulation-flocculation, is also presented.
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Affiliation(s)
- Jayaprakash Saththasivam
- Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Kavithaa Loganathan
- Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Sarper Sarp
- Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar.
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26
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Fadali O, Ebrahiem E, Gamil AE, Altaher H. Investigation of the Electrocoagulation Treatment Technique for the Separation of Oil from Wastewater. ACTA ACUST UNITED AC 2015. [DOI: 10.3923/jest.2016.62.74] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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27
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da Costa Marques MR, de Souza PSA, Rigo MM, Cerqueira AA, de Paiva JL, Merçon F, Perez DV. Effects of untreated and treated oilfield-produced water on seed germination, seedling development, and biomass production of sunflower (Helianthus annuus L.). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:15985-15993. [PMID: 26059762 DOI: 10.1007/s11356-015-4820-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 06/01/2015] [Indexed: 06/04/2023]
Abstract
This study aims to evaluate possible toxic effects of oil and other contaminants from oilfield-produced water from oil exploration and production, on seed germination, and seedling development of sunflower (Helianthus annuus L.). In comparison, as treated by electroflocculation, oilfield-produced water, with lower oil and organic matter content, was also used. Electroflocculation treatment of oilfield-produced water achieved significant removals of chemical oxygen demand (COD) (94 %), oil and grease (O&G) (96 %), color (97 %), and turbidity (99 %). Different O&G, COD, and salt levels of untreated and treated oilfield-produced water did not influence germination process and seedling biomass production. Normal seedlings percentage and vigor tended to decrease more intensely in O&G and COD levels, higher than 337.5 mg L(-1) and 1321 mg O2 L(-1), respectively, using untreated oilfield-produced water. These results indicate that this industrial effluent must be treated, in order to not affect adversely seedling development. This way, electroflocculation treatment appears as an interesting alternative to removing oil and soluble organic matter in excess from oilfield-produced water improving sunflower's seedling development and providing a friendly environmental destination for this wastewater, reducing its potential to harm water resources, soil, and biota.
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Affiliation(s)
- Mônica Regina da Costa Marques
- Environmental Technology Laboratory, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Paulo Sérgio Alves de Souza
- Environmental Technology Laboratory, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Michelle Machado Rigo
- Environmental Technology Laboratory, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Alexandre Andrade Cerqueira
- Environmental Technology Laboratory, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Julieta L de Paiva
- Environmental Technology Laboratory, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Fábio Merçon
- Department of Biochemical Process Technology, Institute of Chemistry, State University of Rio de Janeiro, 20550-900, Rio de Janeiro, RJ, Brazil.
| | - Daniel Vidal Perez
- Brazilian Agricultural Research Corporation, 22460-000, Rio de Janeiro, RJ, Brazil.
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Kuokkanen V, Kuokkanen T, Rämö J, Lassi U. Electrocoagulation treatment of peat bog drainage water containing humic substances. WATER RESEARCH 2015; 79:79-87. [PMID: 25973580 DOI: 10.1016/j.watres.2015.04.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 04/13/2015] [Accepted: 04/17/2015] [Indexed: 06/04/2023]
Abstract
Electrocoagulation (EC) treatment of 100 mg/L synthetic wastewater (SWW) containing humic acids was optimized (achieving 90% CODMn and 80% DOC removal efficiencies), after which real peat bog drainage waters (PBDWs) from three northern Finnish peat bogs were also treated. High pollutant removal efficiencies were achieved: Ptot, TS, and color could be removed completely, while Ntot, CODMn, and DOC/TOC removal efficiencies were in the range of 33-41%, 75-90%, and 62-75%, respectively. Al and Fe performed similarly as the anode material. Large scale experiments (1 m(3)) using cold (T = 10-11 °C) PBDWs were also conducted successfully, with optimal treatment times of 60-120 min (applying current densities of 60-75 A/m(2)). Residual values of Al and Fe (complete removal) were lower than their initial values in the EC-treated PBDWs. Electricity consumption and operational costs in optimum conditions were found to be low and similar for all the waters studied: 0.94 kWh/m(3) and 0.15 €/m(3) for SWW and 0.35-0.70 kWh/m(3) and 0.06-0.12 €/m(3) for the PBDWs (large-scale). Thus, e.g. solar cells could be considered as a power source for this EC application. In conclusion, EC treatment of PBDW containing humic substances was shown to be feasible.
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Affiliation(s)
- V Kuokkanen
- University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland
| | - T Kuokkanen
- University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland.
| | - J Rämö
- University of Oulu, Thule Institute, Cewic, P.O. Box 4300, 90014 Oulu, Finland
| | - U Lassi
- University of Oulu, Research Unit of Sustainable Chemistry, P.O. Box 3000, 90014 Oulu, Finland; University of Jyvaskyla, Kokkola University Consortium Chydenius, P. O. Box 567, FI-67701 Kokkola, Finland
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30
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Karhu M, Kuokkanen T, Rämö J, Mikola M, Tanskanen J. Performance of a commercial industrial-scale UF-based process for treatment of oily wastewaters. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2013; 128:413-420. [PMID: 23792818 DOI: 10.1016/j.jenvman.2013.05.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 05/08/2013] [Accepted: 05/25/2013] [Indexed: 06/02/2023]
Abstract
An evaluation was made of the performance of a commercial industrial-scale ultrafiltration (UF)-based process for treatment of highly concentrated oily wastewaters. Wastewater samples were gathered from two plants treating industrial wastewaters in 2008, and in 2011 (only from one of the plants), from three points of a UF-based treatment train. The wastewater samples were analyzed by measuring the BOD7, COD, TOC and total surface charge (TSC). The inorganic content and zeta potentials of the samples were analyzed and GC-FID/MS analyses were performed. The removal performances of BOD7, COD, TOC and TSC in 2008 and 2011 for both plants were very high. Initial concentrations of contaminants in 2011 were lower than in 2008, therefore the COD and TSC reductions were also lower in 2011 than three years before. Regardless of the high performance of UF-based processes in both plants, at times the residual concentrations were considerable. This could be explained by the high initial concentrations and also by the presence of the dissolved compounds that were characterized. Linear correlation was observed between COD and TOC, and between COD and TSC. The correlation between COD and TSC could be utilized for process control purposes.
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Affiliation(s)
- M Karhu
- Chemical Process Engineering Laboratory, Department of Process and Environmental Engineering, University of Oulu, P.O. Box 4300, 90014 Oulu, Finland.
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Kuokkanen V, Kuokkanen T, Rämö J, Lassi U. Recent Applications of Electrocoagulation in Treatment of Water and Wastewater—A Review. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/gsc.2013.32013] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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