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Vicente C, Silva JR, Santos AD, Silva JF, Mano JT, Castro LM. Electrocoagulation treatment of furniture industry wastewater. CHEMOSPHERE 2023; 328:138500. [PMID: 36963577 DOI: 10.1016/j.chemosphere.2023.138500] [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: 02/07/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 06/18/2023]
Abstract
Electrocoagulation was investigated as a method for treating wastewater containing polyvinyl acetate (PVAc) from the furniture industry. The study evaluated the evolution of iron concentration and passivation during the treatment process. Laboratory-scale experiments were conducted to evaluate the effects of inter-electrode distance (d), current density, and mode on treatment performance. Three values of d (0.3, 0.6, and 0.9 cm) were studied and found to have no significant effect on performance. However, lower d values resulted in reduced energy consumption due to a decrease in applied voltage. Three values of current density (132, 158, and 197 A m-2) were studied under two current modes, Direct Current (DC) and Alternating Pulsed Current (APC). The best treatment performance for DC occurred under 158 A m-2 (the treated wastewater was characterized by pH = 4.59 ± 0.02, conductivity = 996 ± 21 μS cm-1, COD = 1940 ± 55 mgO2 L-1, TSS = 105 ± 14 mg L-1, and Fe = 50.39 ± 1.87 mgFe L-1). For APC, the best performance was achieved under 197 A m-2 (the treated wastewater was characterized by pH = 6.33 ± 0.06, conductivity = 988 ± 17 μS cm-1, COD = 1942 ± 312 mgO2 L-1, TSS = 199 ± 55 mg L-1, and Fe = 44.68 ± 4.60 mgFe L-1). Despite the promising results, treatment performance was insufficient to meet the legal requirements for water discharge. APC was found to be a more economically viable approach, as it reduced anode wear, electrode passivation, and energy consumption. The quantity of iron released increased with d, and the effect of current density on iron concentration was found to be non-linear. However, applying APC reduced the iron content for all tested current densities. The tests showed that EC was effective in removing chemical oxygen demand (COD) and total suspended solids (TSS), achieving removal efficiencies above 92% and 99%, respectively. However, the studied treatment procedures were insufficient to meet the EU legal requirements for water discharge. Therefore, the obtained wastewater should undergo a post-treatment process.
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Affiliation(s)
- Carolina Vicente
- Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal
| | - João R Silva
- Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal; CIEPQPF-Chemical Engineering Processes and Forest Products Research Centre, Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Rua Sílvio Lima, 3030-790, Coimbra, Portugal
| | - Andreia D Santos
- Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal; CIEPQPF-Chemical Engineering Processes and Forest Products Research Centre, Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Rua Sílvio Lima, 3030-790, Coimbra, Portugal
| | - João F Silva
- Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal
| | - Jorge T Mano
- IKEA Industry Portugal, SA, Avenida Capital do Móvel, Nº 157, 4595-282, Penamaior, Portugal
| | - Luis M Castro
- Polytechnic of Coimbra, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal; CIEPQPF-Chemical Engineering Processes and Forest Products Research Centre, Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Rua Sílvio Lima, 3030-790, Coimbra, Portugal; SISus - Laboratory of Sustainable Industrial Systems, Coimbra Institute of Engineering, Department of Chemical and Biological Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199, Coimbra, Portugal.
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Environmental and economic feasibility of the treatment of dairy industry wastewater by photo-Fenton and electrocoagulation process: Multicriteria optimization by desirability function. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.113820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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3
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Hendaoui K, Trabelsi-Ayadi M, Ayari F. Optimization of continuous electrocoagulation-adsorption combined process for the treatment of a textile effluent. Chin J Chem Eng 2022. [DOI: 10.1016/j.cjche.2020.10.047] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Lee H, Kim H, Jeong H. Approaches to Sustainability in Chemical Mechanical Polishing (CMP): A Review. INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING-GREEN TECHNOLOGY 2022; 9:349-367. [PMCID: PMC8617369 DOI: 10.1007/s40684-021-00406-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 09/09/2021] [Accepted: 11/06/2021] [Indexed: 06/01/2023]
Abstract
Chemical mechanical polishing (CMP) is an essential planarization process for semiconductor manufacturing. The application of CMP has been increasing in semiconductor fabrication for highly integrated devices. Recently, environmental burden caused by the CMP process was assessed because of interest in the global environment. In this study, the previously reported impacts of CMP on the environment and studies conducted on developing various methods to reduce environmental burden are reviewed. In addition to analyzing the impacts of CMP, this paper introduces a method for treating CMP wastewater and improving the material removal efficiency through the improvement of CMP consumables. Finally, the authors review research on hybridization of the CMP process and discuss the direction in which CMP technology will progress to improve sustainability in the future.
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Affiliation(s)
- Hyunseop Lee
- Department of Mechanical Engineering, Dong-A University, 37 Nakdong-daero 550beon-gil, Saha-gu, Busan, 49315 Republic of Korea
| | - Hyoungjae Kim
- Korea Institute of Industrial Technology, 42-7 Baehyang-daero 804beon-gil, Sasang-gu, Busan, 46938 Republic of Korea
| | - Haedo Jeong
- School of Mechanical Engineering, Pusan National University, 2 Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241 Republic of Korea
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Suitability of aluminum material on sugar industry wastewater with chemical and electrochemical treatment processes. INTERNATIONAL JOURNAL OF INDUSTRIAL CHEMISTRY 2019. [DOI: 10.1007/s40090-019-00196-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
AbstractAluminum is a valuable material, which can be used for water and wastewater treatment. It exists in metal as well as in salt form. The efficiency of water and wastewater treatment depends upon the technology applied to treat. Sugarcane industry is coming under those industries which have a large amount of freshwater and release large amount of effluent. The goal of this research work is to study the behavior of aluminum metal and salt for the treatment of sugar industry wastewater on chemical oxidation and electrochemical oxidation. The effect of pH, dosing, temperature and catalysis on metal and salt has been also studied with both treatment methods. The results show that maximum 90% of chemical oxygen demand and 94% of color removal can be achieved with an aluminum electrode (electrocoagulation) at optimum conditions, pH 7, current density 178 A/m2, electrode distance 20 mm, and salt solution 0.5 M NaCl. In the same way, 81% chemical oxygen demand and 85% color removal were achieved with alum for the 0.5 M lime solution, at 50 mM mass loading, 21 °C operating temperature and optimum pH of 7, respectively. The sludge generated after treatment was also analyzed with settling filtration, thermal, FTIR and SEM.
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Wiley PE, Trent JD. Clarification of algae-laden water using electrochemical processes. WATER SCIENCE & TECHNOLOGY, WATER SUPPLY 2016; 16:314-323. [PMID: 33414697 PMCID: PMC7786832 DOI: 10.2166/ws.2015.140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Algae contamination of surface water and drinking water supplies is a significant problem particularly in rural areas. A decentralized inexpensive technology that would effectively remove algae from water would be beneficial. Electrocoagulation (EC) combined with electroflotation (EF) as a single process (ECF) is a promising algae harvesting technique with no moving parts that may be powered using a modest array of photovoltaic panels if a low power system can be developed. Here, an ECF system was constructed to study the energy required to remove algae from a simulated drinking water supply. Results from 18 ECF experiments indicated a >95% improvement of water clarity measured by optical density (OD750) could be achieved with as little energy as 1.25 kWh m-3. The key was to find the ideal combination of gas bubbles produced by EF (G) and coagulant from the EC relative to the concentration of suspended solids (S). The ideal gas to solids (G/S) ratio for the ECF system ranged from 0.09 to 0.17. In solutions containing chloride (Cl-) ions ECF produced chlorine gas which is known to contribute to disinfection. Results suggest that ECF can efficiently remove algae and simultaneously contribute to disinfecting contaminated drinking water supplies.
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Affiliation(s)
- Patrick E. Wiley
- PERC Water Corporation, 959 South Coast Drive, Suite 315, Costa Mesa, CA 92626, USA
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Garg KK, Prasad B. Electrochemical treatment of benzoic acid (BA) from aqueous solution and optimization of parameters by response surface methodology (RSM). J Taiwan Inst Chem Eng 2015. [DOI: 10.1016/j.jtice.2015.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Manenti DR, Módenes AN, Soares PA, Boaventura RAR, Palácio SM, Borba FH, Espinoza-Quiñones FR, Bergamasco R, Vilar VJP. Biodegradability and toxicity assessment of a real textile wastewater effluent treated by an optimized electrocoagulation process. ENVIRONMENTAL TECHNOLOGY 2015; 36:496-506. [PMID: 25182075 DOI: 10.1080/09593330.2014.952676] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this work, the application of an iron electrode-based electrocoagulation (EC) process on the treatment of a real textile wastewater (RTW) was investigated. In order to perform an efficient integration of the EC process with a biological oxidation one, an enhancement in the biodegradability and low toxicity of final compounds was sought. Optimal values of EC reactor operation parameters (pH, current density and electrolysis time) were achieved by applying a full factorial 3(3) experimental design. Biodegradability and toxicity assays were performed on treated RTW samples obtained at the optimal values of: pH of the solution (7.0), current density (142.9 A m(-2)) and different electrolysis times. As response variables for the biodegradability and toxicity assessment, the Zahn-Wellens test (Dt), the ratio values of dissolved organic carbon (DOC) relative to low-molecular-weight carboxylates anions (LMCA) and lethal concentration 50 (LC50) were used. According to the Dt, the DOC/LMCA ratio and LC50, an electrolysis time of 15 min along with the optimal values of pH and current density were suggested as suitable for a next stage of treatment based on a biological oxidation process.
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Affiliation(s)
- Diego R Manenti
- a Postgraduate Program of Chemical Engineering , Maringá State University , Av. Colombo 5790, Maringá , PR 87020-900 , Brazil
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Coons JE, Kalb DM, Dale T, Marrone BL. Getting to low-cost algal biofuels: A monograph on conventional and cutting-edge harvesting and extraction technologies. ALGAL RES 2014. [DOI: 10.1016/j.algal.2014.08.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Gerónimo-López C, Vazquez-Arenas J, Picquart M, González I. The energetic conditions determining the active dissolution of carbon steel during electrocoagulation in sulfate media. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.05.069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Secula MS, Stan CS, Cojocaru C, Cagnon B, Cretescu I. Multi-Objective Optimization of Indigo Carmine Removal by an Electrocoagulation/GAC Coupling Process in a Batch Reactor. SEP SCI TECHNOL 2014. [DOI: 10.1080/01496395.2013.871292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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12
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Dassey AJ, Theegala CS. Reducing electrocoagulation harvesting costs for practical microalgal biodiesel production. ENVIRONMENTAL TECHNOLOGY 2014; 35:691-697. [PMID: 24645449 DOI: 10.1080/09593330.2013.842602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Electrocoagulation has shown potential to be a primary microalgae harvesting technique for biodiesel production. However, methods to reduce energy and electrode costs are still necessary for practical application. Electrocoagulation tests were conducted on Nannochloris sp. and Dunaliella sp. using perforated aluminium and iron electrodes under various charge densities. Aluminium electrodes were shown to be more efficient than iron electrodes when harvesting both algal species. Despite the lower harvesting efficiency, however, the iron electrodes were more energy and cost efficient. Operational costs of less than $0.03/L oil were achieved when harvesting Nannochloris sp. with iron electrodes at 35% harvest efficiency, whereas aluminium electrodes cost $0.75/L oil with 42% harvesting efficiency. Increasing the harvesting efficiencies for both aluminium and iron electrodes also increased the overall cost per litre of oil, therefore lower harvesting efficiencies with lower energy inputs was recommended. Also, increasing the culturing salinity to 2 ppt sodium chloride for freshwater Nannochloris sp. was determined practical to improve the electrocoagulation energy efficiency despite a 25% reduction in cell growth.
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Balla W, Essadki AH, Gourich B, Dassaa A, Chenik H, Azzi M. Electrocoagulation/electroflotation of reactive, disperse and mixture dyes in an external-loop airlift reactor. JOURNAL OF HAZARDOUS MATERIALS 2010; 184:710-716. [PMID: 20870356 DOI: 10.1016/j.jhazmat.2010.08.097] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 08/24/2010] [Accepted: 08/25/2010] [Indexed: 05/29/2023]
Abstract
This paper studied the efficiency of electrocoagulation/electroflotation in removing colour from synthetic and real textile wastewater by using aluminium and iron electrodes in an external-loop airlift reactor of 20 L. The disperse dye is a mixture of Yellow terasil 4G, Red terasil 343 150% and Blue terasil 3R02, the reactive dye is a mixture of Red S3B 195, Yellow SPD, Blue BRFS. For disperse dye, the removal efficiency was better using aluminium electrodes, whereas, the iron electrodes showed more efficiency for removing colour for reactive dye and mixed synthetic dye. Both for disperse, reactive and mixed dye, 40 mA cm(-2) and 20 min were respectively the optimal current density and electrolysis time. 7.5 was an optimal initial pH for both reactive and mixed synthetic dye and 6.2 was an optimal initial pH for disperse dye. The colour efficiency reached in general 90%. The results showed also that Red and Blue disappeared quickly comparatively to the Yellow component both for reactive and disperse dyes. The real textile wastewater was then used. Three effluents were also used: disperse, reactive and the mixture. The colour efficiency is between 70 and 90% and COD efficiency reached 78%. The specific electrical energy consumption per kg dye removed (E(dye)) in optimal conditions for real effluent was calculated. 170 kWh/kg(dye) was required for a reactive dye, 120 kWh/kg(dye) for disperse and 50 kWh/kg(dye) for the mixture.
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Affiliation(s)
- Wafaa Balla
- Ecole Supérieure de Technologie, Laboratoire Génie des Procédés et Environnement, B.P. 8012, Oasis, Casablanca, Morocco; Faculté des sciences Aïn Chock, Laboratoire d'Electrochimie et chimie de l'environnement, B.P. 5366, Maarif, Casablanca, Morocco
| | - A H Essadki
- Ecole Supérieure de Technologie, Laboratoire Génie des Procédés et Environnement, B.P. 8012, Oasis, Casablanca, Morocco.
| | - B Gourich
- Ecole Supérieure de Technologie, Laboratoire Génie des Procédés et Environnement, B.P. 8012, Oasis, Casablanca, Morocco
| | - A Dassaa
- Faculté des sciences Aïn Chock, Laboratoire d'Electrochimie et chimie de l'environnement, B.P. 5366, Maarif, Casablanca, Morocco
| | - H Chenik
- Ecole Supérieure de Technologie, Laboratoire Génie des Procédés et Environnement, B.P. 8012, Oasis, Casablanca, Morocco; Faculté des sciences Aïn Chock, Laboratoire d'Electrochimie et chimie de l'environnement, B.P. 5366, Maarif, Casablanca, Morocco
| | - M Azzi
- Faculté des sciences Aïn Chock, Laboratoire d'Electrochimie et chimie de l'environnement, B.P. 5366, Maarif, Casablanca, Morocco
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Labanowski J, Pallier V, Feuillade-Cathalifaud G. Study of organic matter during coagulation and electrocoagulation processes: application to a stabilized landfill leachate. JOURNAL OF HAZARDOUS MATERIALS 2010; 179:166-172. [PMID: 20303652 DOI: 10.1016/j.jhazmat.2010.02.074] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 02/05/2010] [Accepted: 02/22/2010] [Indexed: 05/29/2023]
Abstract
Organic matter contained in leachates appears to be a relevant indicator of waste evolution. Among the physico-chemical treatments applied to stabilize leachates, coagulation-flocculation is considered a classical process and electrocoagulation can be developed. Electrocoagulation tests were carried out in a laboratory pilot using aluminium plates and compared to classical coagulation-flocculation with aluminium ions and to electrolysis alone. The leachate used in this study came from the landfill of Crezin (Limoges, France) and it presented low biodegradability and high concentration of macromolecules. To assess the efficiency of the chemical and electrochemical processes, we specifically studied Organic Matter (OM) by using two protocols: adsorption on XAD resins and fractionation by ultrafiltration. Biodegradable Dissolved Organic Carbon (BDOC) measurements were applied to the fractions extracted by XAD resins and were also used as an indicator of the efficiency of the treatments. Residual organic matter concentration was the same for the two processes but its composition appeared different after electrocoagulation: a higher percentage of small hydrophilic organic molecules which seemed to be less biodegradable than the initial organic matter was observed.
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Affiliation(s)
- J Labanowski
- Laboratoire de Chimie et Microbiologie de l'Eau UMR CNRS 6008, Université de Poitiers-ESIP, 40, Avenue du recteur Pineau, 86022 Poitiers Cedex, France.
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15
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Meunier N, Drogui P, Mercier G, Blais JF. Treatment of metal-loaded soil leachates by electrocoagulation. Sep Purif Technol 2009. [DOI: 10.1016/j.seppur.2009.03.040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Bukhari AA. Investigation of the electro-coagulation treatment process for the removal of total suspended solids and turbidity from municipal wastewater. BIORESOURCE TECHNOLOGY 2008; 99:914-21. [PMID: 17499502 DOI: 10.1016/j.biortech.2007.03.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 03/09/2007] [Accepted: 03/12/2007] [Indexed: 05/13/2023]
Abstract
In this work, raw municipal wastewater was electro-coagulated for the removal of total suspended solids (TSS), turbidity, and particulate BOD using stainless steel electrodes. The removal efficiency of TSS and turbidity is shown to depend on the amount of iron generated from the anode of the reactive electrode used in this study, when applying the lower currents of 0.05 A and 0.1A. For such lower currents, the results suggested that the removal is consistent with charge neutralization coagulation mechanism. When applying higher currents of 0.2 A, 0.4 A, and 0.8 A, the results suggested that the dominant removal mechanism is sweep-floc coagulation as the generated soluble ferrous ions are converted to insoluble ferric ions due to oxidation with chlorine generated during the electrochemical process at the higher currents. The highest TSS removal efficiency of 95.4% occurred at a current of 0.8A and contact time of 5 min. The effect of electro-coagulation on the removal of particulate BOD was shown to depend on the TSS removal efficiency.
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Affiliation(s)
- Alaadin A Bukhari
- Department of Civil Engineering, King Fahd University of Petroleum and Minerals, PO Box 1960, Dhahran, Saudi Arabia.
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Mouedhen G, Feki M, Wery MDP, Ayedi HF. Behavior of aluminum electrodes in electrocoagulation process. JOURNAL OF HAZARDOUS MATERIALS 2008; 150:124-35. [PMID: 17537574 DOI: 10.1016/j.jhazmat.2007.04.090] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 04/16/2007] [Accepted: 04/17/2007] [Indexed: 05/15/2023]
Abstract
In the present work, electrocoagulation process with aluminum electrodes was investigated. Different operational conditions such as composition of Na(2)SO(4) based solutions, pH and current density were examined in a systematic manner. Their influence on (i) electrode polarization phenomena, (ii) pH evolution during electrolysis and (iii) the amount of Al released (coagulant) was investigated. For this purpose, potentiodynamic tests and electrolyses using different electrochemical cell configurations were conducted. It is mainly found that (i) a minimum Cl(-) concentration of the electrolyte of about 60ppm is required to breakdown the anodic passive film and considerably reduce the cell voltage during electrolysis; (ii) the anodic dissolution efficiency is unit; (iii) the global amount of coagulant (Al(3+)) generated has two origins: electrochemical oxidation of the anode and "chemical" attack of the cathode and (iv) electrolysis with Al electrodes acts as pH neutralization of the electrolytic medium. Taking into account advantage of the pH evolution observed during electrolysis, electrocoagulation tests were performed to treat a synthetic wastewater containing heavy metallic ions (Ni(2+), Cu(2+), Zn(2+)). Removal efficiencies over 98% were reached. Furthermore, our results displayed prominently that an increase of current density notably reduces the treatment duration without inducing a strong increase of the charge loading.
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Affiliation(s)
- G Mouedhen
- Unité de Chimie Industrielle et Matériaux (UCIM), ENIS, B.P.W. Sfax, Tunisie
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Yilmaz AE, Boncukcuoğlu R, Kocakerim MM. A quantitative comparison between electrocoagulation and chemical coagulation for boron removal from boron-containing solution. JOURNAL OF HAZARDOUS MATERIALS 2007; 149:475-81. [PMID: 17524554 DOI: 10.1016/j.jhazmat.2007.04.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Revised: 04/02/2007] [Accepted: 04/05/2007] [Indexed: 05/15/2023]
Abstract
This paper provides a quantitative comparison of electrocoagulation and chemical coagulation approaches based on boron removal. Electrocoagulation process delivers the coagulant in situ as the sacrificial anode corrodes, due to a fixed current density, while the simultaneous evolution of hydrogen at the cathode allows for pollutant removal by flotation. By comparison, conventional chemical coagulation typically adds a salt of the coagulant, with settling providing the primary pollutant removal path. Chemical coagulation was carried out via jar tests using aluminum chloride. Comparison was done with the same amount of coagulant between electrocoagulation and chemical coagulation processes. Boron removal obtained was higher with electrocoagulation process. In addition, it was seen that chemical coagulation has any effect for boron removal from boron-containing solution. At optimum conditions (e.g. pH 8.0 and aluminum dose of 7.45 g/L), boron removal efficiencies for electrocoagulation and chemical coagulation were 94.0% and 24.0%, respectively.
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Affiliation(s)
- A Erdem Yilmaz
- Atatürk University, Faculty of Engineering, Department of Environmental Engineering, 25240 Erzurum, Turkey.
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Raghu S, Ahmed Basha C. Chemical or electrochemical techniques, followed by ion exchange, for recycle of textile dye wastewater. JOURNAL OF HAZARDOUS MATERIALS 2007; 149:324-30. [PMID: 17512112 DOI: 10.1016/j.jhazmat.2007.03.087] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 03/30/2007] [Accepted: 03/30/2007] [Indexed: 05/07/2023]
Abstract
This paper examines the use of chemical or electrocoagulation treatment process followed by ion-exchange process of the textile dye effluent. The dye effluent was treated using polymeric coagulant (cationic dye-fixing agent) or electrocoagulation (iron and aluminum electrode) process under various conditions such as various current densities and effect of pH. Efficiencies of COD reduction, colour removal and power consumption were studied for each process. The chemical or electrochemical treatment are indented primarily to remove colour and COD of wastewater while ion exchange is used to further improve the removal efficiency of the colour, COD, Fe concentration, conductivity, alkalinity and total dissolved solids (TDS). From the results chemical coagulation, maximum COD reduction of about 81.3% was obtained at 300 mg/l of coagulant whereas in electrocoagulation process, maximum COD removal of about 92.31% (0.25 A/dm2) was achieved with energy consumption of about 19.29 k Wh/kg of COD and 80% (1A/dm(2)) COD removal was obtained with energy consumption of about 130.095 k Wh/kg of COD at iron and aluminum electrodes, respectively. All the experimental results, throughout the present study, have indicated that chemical or electrocoagulation treatment followed by ion-exchange methods were very effective and were capable of elevating quality of the treated wastewater effluent to the reuse standard of the textile industry.
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Affiliation(s)
- S Raghu
- Central Electrochemical Research Institute, Karaikudi 630 006, Tamilnadu, India
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Yildiz YS, Koparal AS, Irdemez S, Keskinler B. Electrocoagulation of synthetically prepared waters containing high concentration of NOM using iron cast electrodes. JOURNAL OF HAZARDOUS MATERIALS 2007; 139:373-80. [PMID: 16863679 DOI: 10.1016/j.jhazmat.2006.06.044] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2006] [Revised: 06/13/2006] [Accepted: 06/14/2006] [Indexed: 05/11/2023]
Abstract
The aim of this investigation is to evaluate the treatability of synthetically prepared water with high concentration of humic substances by electrocoagulation in batch mode using iron cast electrodes. Effects of applied potential, initial humic substance concentration and supporting electrolyte type on humic substance removal efficiency were investigated. NaNO3, Na2SO4 and NaCl were used as supporting electrolyte. Among these supporting electrolytes, Na2SO4 and NaCl have provided high removal efficiencies, whereas in the experiments using NaNO3 as supporting electrolyte have been observed no flock formation. The highest removal rate is obtainable with NaCl as supporting electrolyte. Removal efficiencies for initial humic substance concentration of 500 mg L-1 with NaCl and Na2SO4 equal to 97.95% for 35 min and 92.69% for 70 min, respectively. This behavior of the system has been derived from oxidation products, available in the bulk solution, of chloride ions. When NaCl is used as supporting electrolyte, there is an advantage of providing the disinfection of water, but humic substances and chloride ions are available in the bulk solution with risk of formation undesirable organo-chlorine compounds, so the Na2SO4 is the most favorable supporting electrolyte.
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Affiliation(s)
- Yalçin Sevki Yildiz
- Department of Environmental Engineering, Atatürk University, 25240 Erzurum, Turkey.
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İrdemez Ş, Demircioğlu N, Yıldız YŞ, Bingül Z. The effects of current density and phosphate concentration on phosphate removal from wastewater by electrocoagulation using aluminum and iron plate electrodes. Sep Purif Technol 2006. [DOI: 10.1016/j.seppur.2006.04.008] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bayramoglu M, Kobya M, Eyvaz M, Senturk E. Technical and economic analysis of electrocoagulation for the treatment of poultry slaughterhouse wastewater. Sep Purif Technol 2006. [DOI: 10.1016/j.seppur.2006.03.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Mahesh S, Prasad B, Mall ID, Mishra IM. Electrochemical Degradation of Pulp and Paper Mill Wastewater. Part 1. COD and Color Removal. Ind Eng Chem Res 2006. [DOI: 10.1021/ie0514096] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Mahesh
- Department of Chemical Engineering, Indian Institute of Technology, Roorkee, Roorkee−247 667, Uttaranchal, India
| | - B. Prasad
- Department of Chemical Engineering, Indian Institute of Technology, Roorkee, Roorkee−247 667, Uttaranchal, India
| | - I. D. Mall
- Department of Chemical Engineering, Indian Institute of Technology, Roorkee, Roorkee−247 667, Uttaranchal, India
| | - I. M. Mishra
- Department of Chemical Engineering, Indian Institute of Technology, Roorkee, Roorkee−247 667, Uttaranchal, India
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Cañizares P, Carmona M, Lobato J, Martínez F, Rodrigo MA. Electrodissolution of Aluminum Electrodes in Electrocoagulation Processes. Ind Eng Chem Res 2005. [DOI: 10.1021/ie048858a] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- P. Cañizares
- Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M. Carmona
- Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - J. Lobato
- Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - F. Martínez
- Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M. A. Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
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Holt PK, Barton GW, Mitchell CA. The future for electrocoagulation as a localised water treatment technology. CHEMOSPHERE 2005; 59:355-367. [PMID: 15763088 DOI: 10.1016/j.chemosphere.2004.10.023] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2004] [Revised: 10/15/2004] [Accepted: 10/19/2004] [Indexed: 05/24/2023]
Abstract
Electrocoagulation is an electrochemical method of treating polluted water whereby sacrificial anodes corrode to release active coagulant precursors (usually aluminium or iron cations) into solution. Accompanying electrolytic reactions evolve gas (usually as hydrogen bubbles) at the cathode. Electrocoagulation has a long history as a water treatment technology having been employed to remove a wide range of pollutants. However electrocoagulation has never become accepted as a 'mainstream' water treatment technology. The lack of a systematic approach to electrocoagulation reactor design/operation and the issue of electrode reliability (particularly passivation of the electrodes over time) have limited its implementation. However recent technical improvements combined with a growing need for small-scale decentralised water treatment facilities have led to a re-evaluation of electrocoagulation. Starting with a review of electrocoagulation reactor design/operation, this article examines and identifies a conceptual framework for electrocoagulation that focuses on the interactions between electrochemistry, coagulation and flotation. In addition detailed experimental data are provided from a batch reactor system removing suspended solids together with a mathematical analysis based on the 'white water' model for the dissolved air flotation process. Current density is identified as the key operational parameter influencing which pollutant removal mechanism dominates. The conclusion is drawn that electrocoagulation has a future as a decentralised water treatment technology. A conceptual framework is presented for future research directed towards a more mechanistic understanding of the process.
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Affiliation(s)
- Peter K Holt
- Department of Chemical Engineering, University of Sydney, NSW 2006, Sydney, Australia.
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Bayramoglu M, Kobya M, Can OT, Sozbir M. Operating cost analysis of electrocoagulation of textile dye wastewater. Sep Purif Technol 2004. [DOI: 10.1016/j.seppur.2003.09.002] [Citation(s) in RCA: 287] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Can OT, Bayramoglu M, Kobya M. Decolorization of Reactive Dye Solutions by Electrocoagulation Using Aluminum Electrodes. Ind Eng Chem Res 2003. [DOI: 10.1021/ie020951g] [Citation(s) in RCA: 210] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- O. T. Can
- Engineering Faculty, Department of Environmental Engineering, Gebze Institute of Technology, 41400 Gebze, Turkey
| | - M. Bayramoglu
- Engineering Faculty, Department of Environmental Engineering, Gebze Institute of Technology, 41400 Gebze, Turkey
| | - M. Kobya
- Engineering Faculty, Department of Environmental Engineering, Gebze Institute of Technology, 41400 Gebze, Turkey
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Calvo LS, Leclerc JP, Tanguy G, Cames MC, Paternotte G, Valentin G, Rostan A, Lapicque F. An electrocoagulation unit for the purification of soluble oil wastes of high COD. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/ep.670220117] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mollah MY, Schennach R, Parga JR, Cocke DL. Electrocoagulation (EC)--science and applications. JOURNAL OF HAZARDOUS MATERIALS 2001; 84:29-41. [PMID: 11376882 DOI: 10.1016/s0304-3894(01)00176-5] [Citation(s) in RCA: 423] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Although electrocoagulation is an evolving technology that is being effectively applied today for wastewater treatment, the paucity of scientific understanding of the complex chemical and physical processes involved is limiting future design and hindering progress. The objective of this review through a survey of the literature is to bring the chemistry and physical processes involved into perspective and to focus attention on those areas critically needing research.
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Affiliation(s)
- M Y Mollah
- Gill Chair of Chemistry & Chemical Engineering, Lamar University, Beaumont, TX 77710, USA
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