Evaluation of Magnetic Stirring and Aeration on Electrocoagulation Performance in Actual Industrial Treatment

Agitation was a significant factor in achieving the high performance of the electrocoagulation (EC) system. Three EC systems with four parellal monopolar Al electrodes were established to clarify the influence of agitation methods on pollutants removal efficiency; magnetic stirring, continuous aeration, and combination of magnetic stirring and aeration. The aim of this work was to maximize industrial wastewater treatment in a short detention time and to understand the mechanisms that occurred in different EC systems. The coolant wastewater from the aluminum product industry was represented as industrial wastewater. The hybrid stirring-aeration EC system obtained a lower COD removal compared to the stirring EC system and the aeration EC system. Although aeration can cause an increase in COD removal due to complete circulation and effective coagulant formation of Fe (OH), however, the combination of aeration and stirring negatively affected the performance of CE. The possible reason was that the excessive agitation led to a rapid mixing of the solution, and then the coagulants and pollutants obtained insufficient time to form flocs to precipitate. The best EC performance was observed in the aeration EC system, followed by the stirring EC system, control system (without agitations), and the stirring aeration EC system, respectively, in the short detention time of 15 min. Furthermore, all EC systems could achieve an excellent COD removal of 91% when the detention time was sufficient (eg, 45 min for the stirring aeration EC system). Furthermore, the decreasing number of electrodes affected the COD removal efficiency, whereas the NaCl additive was insignificantly affected.

[1]  A. Mounteer,et al.  Electrocoagulation of kraft pulp bleaching filtrates to improve biotreatability , 2021 .

[2]  T. Brányik,et al.  Electrocoagulation reduces harvesting costs for microalgae. , 2020, Bioresource technology.

[3]  W. Sunanda,et al.  Effect of electrode numbers in electrocoagulation of Batik Cual wastewater: analysis on water quality and energy used , 2020, IOP Conference Series: Earth and Environmental Science.

[4]  G. Asadollahfardi,et al.  A new combined electrocoagulation-electroflotation process for pretreatment of synthetic and real Moquette-manufacturing industry wastewater: Optimization of operating conditions , 2020 .

[5]  C. Vial,et al.  Treatment of dairy wastewater by electrocoagulation process: Advantages of combined iron/aluminum electrodes , 2020, Separation Science and Technology.

[6]  M. Suresh Kumar,et al.  Treatment of dairy industry wastewater by combined aerated electrocoagulation and phytoremediation process. , 2020, Chemosphere.

[7]  V. Preethi,et al.  Optimization of batch electrocoagulation process using Box-Behnken experimental design for the treatment of crude vegetable oil refinery wastewater , 2020, Journal of Dispersion Science and Technology.

[8]  M. Suresh Kumar,et al.  Arsenite removal from aqueous solution by aerated iron electrocoagulation process , 2019 .

[9]  A. Nakaruk,et al.  Electrocoagulation for spent coolant from machinery industry , 2018 .

[10]  A. Rahmani,et al.  New batch electro-coagulation process for treatment and recovery of high organic load and low volume egg processing industry wastewater , 2018, Process Safety and Environmental Protection.

[11]  M. Kumar,et al.  Composite wastewater treatment by aerated electrocoagulation and modified peroxi-coagulation processes. , 2018, Chemosphere.

[12]  D. Nematollahi,et al.  Combined electrocoagulation/electrooxidation process for the COD removal and recovery of tannery industry wastewater , 2018 .

[13]  Ülker Bakır Öğütveren,et al.  Electrochemical treatment of wastewaters from poultry slaughtering and processing by using iron electrodes , 2018 .

[14]  S. Chelliapan,et al.  A review of electrocoagulation technology for the treatment of textile wastewater , 2017 .

[15]  Li Yu,et al.  A review of treating oily wastewater , 2017 .

[16]  Patrick Drogui,et al.  Electrocoagulation process in water treatment: A review of electrocoagulation modeling approaches , 2017 .

[17]  G. Marfé,et al.  The evidence of toxic wastes dumping in Campania, Italy. , 2016, Critical reviews in oncology/hematology.

[18]  M. M. Emamjomeh,et al.  Electrocoagulation/Flotation of Textile Wastewater with Simultaneous Application of Aluminum and Iron as Anode , 2014, Environmental Processes.

[19]  Carmen Teodosiu,et al.  Advances in preconcentration/removal of environmentally relevant heavy metal ions from water and wastewater by sorbents based on polyurethane foam , 2014 .

[20]  E. Demirbas,et al.  Removal of arsenic from drinking water by batch and continuous electrocoagulation processes using hybrid Al‐Fe plate electrodes , 2014 .

[21]  Y. Yıldız,et al.  The effect of stirring speed and current density on removal efficiency of poultry slaughterhouse wastewater by electrocoagulation method , 2011 .

[22]  Fatih Ilhan,et al.  Treatment of leachate by electrocoagulation using aluminum and iron electrodes. , 2008, Journal of hazardous materials.

[23]  A. S. Koparal,et al.  Effect of initial pH and supporting electrolyte on the treatment of water containing high concentration of humic substances by electrocoagulation , 2008 .

[24]  N. Hilal,et al.  Treatment of waste coolants by coagulation and membrane filtration , 2004 .

[25]  F. Lapicque,et al.  An electrocoagulation unit for the purification of soluble oil wastes of high COD , 2003 .

[26]  S. Moon,et al.  A Study on Removal of Cobalt from a Primary Coolant by Continuous Electrodeionization with Various Conducting Spacers , 2003 .

[27]  A. Sancha The removal of arsenic , 2000 .

[28]  A. Rahmani,et al.  A Central Composite Design to Optimize In-Situ Electrochemically Produced Ozone for Removal of Reactive Red 198 , 2018 .