Electrochemical treatment and operating cost analysis of textile wastewater using sacrificial iron electrodes

Electrocoagulation (EC) method with iron electrode was used to treat the textile wastewater in a batch reactor. Iron electrode material was used as a sacrificial electrode in monopolar parallel mode in this study. The removal efficiencies of the wastewater by EC were affected by initial pH of the solution, current density, conductivity and time of electrolysis. Under the optimal experimental conditions (initial pH 6.9, current density of 10 mA/cm2, conductivity of 3,990 μS/cm, and electrolysis time of 10 min), the treatment of textile wastewater by the EC process led to a removal capacity of 78% of chemical oxygen demand (COD) and 92% of turbidity. The energy and electrode consumptions at the optimum conditions were calculated to be 0.7 kWh/kg COD (1.7 kWh/m3) and 0.2 kgFe/kg COD (0.5 kgFe/m3), respectively. Moreover, the operating cost was calculated as 0.2 €/kg removed COD or 0.5 €/m3 treated wastewater. Zeta potential measurement was used to determine the charge of particle formed during the EC which revealed that Fe(OH)3 might be responsible for the EC process.

Download Full-text

COD removal from leachate by electrocoagulation process: treatment with monopolar electrodes in parallel connection

Water Science & Technology ◽

10.2166/wst.2017.528 ◽

2017 ◽

Vol 77 (1) ◽

pp. 177-186 ◽

Cited By ~ 6

Author(s):

Mehtap Tanyol ◽

Aysenur Ogedey ◽

Ensar Oguz

Keyword(s):

Current Density ◽

Operating Cost ◽

Oxygen Demand ◽

Electrical Energy ◽

Cod Removal ◽

Iron Electrode ◽

Time Intervals ◽

Electrode Distance ◽

Electrocoagulation Process ◽

Monopolar Electrodes

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.

Download Full-text

Combined electrocoagulation and electro-oxidation of industrial textile wastewater treatment in a continuous multi-stage reactor

Water Science & Technology ◽

10.2166/wst.2017.415 ◽

2017 ◽

Vol 76 (9) ◽

pp. 2515-2525 ◽

Cited By ~ 6

Author(s):

Edison GilPavas ◽

Paula Arbeláez-Castaño ◽

José Medina ◽

Diego A. Acosta

Keyword(s):

Wastewater Treatment ◽

Current Density ◽

Design Of Experiment ◽

Operating Cost ◽

Oxygen Demand ◽

Textile Wastewater ◽

Fractional Factorial ◽

Multi Stage ◽

Electro Oxidation ◽

Textile Wastewater Treatment

Abstract A combined electrocoagulation (EC) and electrochemical oxidation (EO) industrial textile wastewater treatment potential is evaluated in this work. A fractional factorial design of experiment showed that EC current density, followed by pH, were the most significant factors. Conductivity and number of electrooxidation cells did not affect chemical oxygen demand degradation (DCOD). Aluminum and iron anodes performed similarly as sacrificial anodes. Current density, pH and conductivity were chosen for a Box–Behnken design of experiment to determine optimal conditions to achieve a high DCOD minimizing operating cost (OC). The optimum to achieve a 70% DCOD with an OC of USD 1.47/m3 was: pH of 4, a conductivity of 3.7 mS/cm and a current density of 4.1 mA/cm2. This study also shows the applicability of a combined EC/EO treatment process of a real complex industrial wastewater.

Download Full-text

Optimization of material and energy consumption for removal of Acid Red 14 by simultaneous electrocoagulation and electroflotation

Water Science & Technology ◽

10.2166/wst.2015.477 ◽

2015 ◽

Vol 73 (1) ◽

pp. 192-202 ◽

Cited By ~ 14

Author(s):

Amin Hooshmandfar ◽

Bita Ayati ◽

Ahmad Khodadadi Darban

Keyword(s):

Electrical Conductivity ◽

Energy Consumption ◽

Current Density ◽

Specific Energy Consumption ◽

Textile Wastewater ◽

Electrical Energy ◽

Treated Wastewater ◽

Bubble Generation ◽

Initial Ph ◽

Anode Dissolution

Decolorization of wastewater of industries which consume dye is an environmental priority. Electrocoagulation and electroflotation methods are appropriate for treatment of these wastewaters. This study investigates the effect of four parameters, electrical conductivity, current density, initial dye concentration, and initial pH, on the performance of a simultaneous electrocoagulation/electroflotation system for removal of Acid Red 14. The optimum values of these parameters were determined based on the amount of electrical energy and aluminum consumption and the best performance of coagulation and bubble generation. The optimum condition was revealed to be electrical conductivity = 1,600 μS/cm, current density = 60 mA/cm2, initial dye concentration = 185 mg/L and initial pH = 7. After less than 180 min of electrolysis, 90% dye removal was achieved with a specific energy consumption = 102 kWh/kg dyeremoved, anode dissolution = 2.09 kg Al/kg dyeremoved and sludge total suspended solids = 15,050 mg/L. Liquid chromatography–UV–mass spectroscopy analyses were conducted on samples of raw and treated wastewater. Results showed that intermediate compounds formed from the breaking of the dye molecules. The advantages of this method are a low material and energy consumption. The amount of produced sludge was low; consequently sludge disposal and management costs would be reduced. This method should be used cautiously for treatment of textile wastewater due to the formation of intermediate compounds.

Download Full-text

Electrochemical Treatment of Simulated Dye Wastewater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.555 ◽

2012 ◽

Vol 441 ◽

pp. 555-558

Author(s):

Feng Tao Chen ◽

San Chuan Yu ◽

Xing Qiong Mu ◽

Shi Shen Zhang

Keyword(s):

Current Density ◽

Oxygen Demand ◽

Electrochemical Treatment ◽

Dye Wastewater ◽

Electrolysis Time ◽

Electrochemical Degradation ◽

Mild Conditions ◽

Thermal Decomposition Method ◽

Initial Ph ◽

Effects Of Ph

The Ti/SnO2-Sb2O3/PbO2 electrodes were prepared by thermal decomposition method and its application in the electrochemical degradation of a heteropolyaromatic dye, Methylene blue (MB), contained in simulated dye wastewater were investigated under mild conditions. The effects of pH, current density and electrolysis time on de-colorization efficiency were also studied. Chemical oxygen demand (COD) was selected as another parameter to evaluate the efficiency of this degradation method on treatment of MB wastewater. The results revealed that when initial pH was 6.0, current density was 50 mA·cm2, electrolysis time was 60 min, Na2SO4 as electrolyte and its concentration was 3.0 g·dm3, the de-colorization and COD removal efficiency can reach 89.9% and 71.7%, respectively.

Download Full-text

Optimization and statistical analysis of sono-Fenton treated wastewater of food industry using reactor by response surface method

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2021-0105 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Vijay A. Juwar ◽

Ajit P. Rathod

Keyword(s):

Reaction Time ◽

Response Surface ◽

Food Industry ◽

Batch Reactor ◽

Oxygen Demand ◽

Volume Ratio ◽

Cod Removal ◽

Treated Wastewater ◽

Experimental Result ◽

Molar Ratio

Abstract The present study deals with the treatment of complex waste (WW) treated for removal of chemical oxygen demand (COD) of the food industry by a sono-Fenton process using a batch reactor. The response surface methodology (RSM) was employed to investigate the five independent variables, such as reaction time, the molar ratio of H2O2/Fe2+, volume ratio of H2O2/WW, pH of waste, and ultrasonic density on COD removal. The experimental data was optimized. The optimization yields the conditions: Reaction time of 24 min, HP:Fe molar ratio of 2.8, HP:WW volume ratio of 1.9 ml/L, pH of 3.6 and an ultrasonic density of 1.8 W/L. The predicted value of COD was 91% and the experimental result was 90%. The composite desirability value (D) of the predicted percent of COD removal at the optimized level of variables was close to one (D = 0.991).

Download Full-text

Decontamination of synthetic textile wastewater by electrochemical processes: energetic and toxicological evaluation

Water Science & Technology ◽

10.2166/wst.2012.431 ◽

2012 ◽

Vol 66 (12) ◽

pp. 2586-2596 ◽

Cited By ~ 1

Author(s):

Y. Mountassir ◽

A. Benyaich ◽

M. Rezrazi ◽

P. Berçot ◽

L. Gebrati

Keyword(s):

Current Density ◽

Organic Contaminants ◽

Operating Time ◽

Oxygen Demand ◽

Textile Wastewater ◽

Toxicological Evaluation ◽

Textile Materials ◽

Titanium Electrode ◽

Electrochemical Processes ◽

Influence Of Ph

The treatment of a synthetic textile wastewater, prepared with several compounds used in the finishing of textile materials, was comparatively studied by electrochemical methods such as electrooxidation (EO) (titanium electrode) and electrocoagulation (EC) (with aluminum and iron electrodes). The influence of pH, current density and operating time on the treatment was assessed by the parameters used to measure the level of organic contaminants in the wastewater; i.e. color, toxicity and chemical oxygen demand (COD). The experimental results showed that an effective electrochemical oxidation was achieved in which the wastewater was decolorized and 92% of COD was completely eliminated. In particular, the mineralization took place by indirect oxidation, mediated by active chlorine, and the treatment efficiency was enhanced by the addition of NaCl to the wastewater and by increasing the applied current density. The toxicity, still higher than the toxicity of the raw effluent, indicated a presence of toxic products after EO. Good results were obtained with the Al and Fe electrodes, mainly with respect to the removal of color and toxicity. EC is more economical than EO and the toxicity evaluation with the Daphnia magna test shows a significant reduction after EC.

Download Full-text

Combined Electrocoagulation and Chemical Coagulation in Treating Brewery Wastewater

Water ◽

10.3390/w12030726 ◽

2020 ◽

Vol 12 (3) ◽

pp. 726 ◽

Cited By ~ 2

Author(s):

Kimberly Swain ◽

Bassim Abbassi ◽

Chris Kinsley

Keyword(s):

Energy Consumption ◽

Nutrient Removal ◽

Operating Cost ◽

Research Work ◽

Oxygen Demand ◽

High Strength ◽

Brewery Wastewater ◽

Chemical Coagulation ◽

Electrode Consumption ◽

Initial Ph

Significant over-strength discharge fees are often imposed on breweries for the disposal of high-strength effluent to sanitary sewers. In this research work, the removal performances of electrocoagulation (EC) compared with operating electrocoagulation and chemical coagulation in sequence (EC-CC) or vice-versa (CC-EC) was examined to determine the capability of treatment in reducing the strength of the wastewater. Optimal operating parameters regarding electrolysis time, initial pH, and applied power were determined in conjunction with nutrient removal performance, electrode consumption and energy usage. Combined EC-CC treatment has been demonstrated to be economically feasible for brewery wastewater applications from an energy consumption perspective due to the efficiency of nutrient removal and the reduction of sewer discharge costs. Treatment by EC-CC at 5 W for 20 min using aluminum electrodes resulted in enhanced and consistent removal efficiencies of 26%, 74%, 76%, and 85% for chemical oxygen demand (COD), reactive phosphorous (RP), total phosphorous (TP) and total suspended solids (TSS), respectively. Energy consumption was the main contributor to operating cost. By considering potential recovered over-strength discharge fees (ODF), EC-CC treatment is economically feasible and beneficial in a brewery wastewater application. The results demonstrated the effectiveness of the CC-EC process to remove phosphorous, organics and solids from brewery wastewater at lower power supply, so that the recovered ODF cost for CC-EC at 5 W-EC is 23% higher than at 10 W-EC.

Download Full-text

Study on Anodic Oxidation parameters for removal of pesticide Imidacloprid on a modified tantalum surface by lead dioxide film

Global NEST Journal ◽

10.30955/gnj.003119 ◽

2020 ◽

Keyword(s):

Current Density ◽

Crop Production ◽

Ph Value ◽

Lead Dioxide ◽

Oxygen Demand ◽

Electrochemical Process ◽

Order Kinetic ◽

Initial Ph ◽

Transport Control ◽

Dioxide Film

The commercial imidacloprid (IMD) insecticide [1-(6-chloro-3-pyridinyl) methyl-4,5-dihydro-N-nitro-1H-imidazole-2-amine] is widely used for the enhancement of crop production, but the intensive use of this insecticide has caused serious environmental problems. This work presents an electrochemical process for the removal of this insecticide using galvanostatic electrolysis at modified tantalum surface by lead dioxide film anode (Ta(PbO2)) anode. The electrolytic process was monitored by chemical oxygen demand (COD). The influence of operating parameters, such as current density, initial concentration of IMD, temperature and initial pH value was investigated. The COD decay follows a pseudo first-order kinetic and the process was under mass transport control. COD removal reach 97% when using an apparent current density of 100 mA cm−2, initial COD of 953 mg L−1 and at 25 °C after 4.5 h electrolysis time.

Download Full-text

Application of Doehlert design for optimization of the electroflotation method for the treatment of wastewater from poultry slaughtering and processing

Research Society and Development ◽

10.33448/rsd-v9i12.10556 ◽

2020 ◽

Vol 9 (12) ◽

pp. e11491210556

Author(s):

Mariana Lopes Bastos ◽

Joel Marques da Silva ◽

Silvânio Silvério Lopes da Costa ◽

Joel Alonso Palomino-Romero

Keyword(s):

Current Density ◽

Treatment Time ◽

Operating Cost ◽

Oxygen Demand ◽

Operating Conditions ◽

Optimum Process ◽

Process Conditions ◽

Doehlert Design ◽

Density Treatment ◽

Suitable Process

In this work, an electroflotation (EF) method for the treatment of poultry slaughterhouse effluent was proposed, and its efficiency in reducing chemical oxygen demand (COD) was investigated. The following operating conditions were optimized through Doehlert design: [Al2(SO4)3], pH, treatment time, and current density. Treatment of the effluent was carried out in a reactor with TiO2–RuO2 (anode) and iron (cathode) electrodes. The optimum process conditions were obtained with a pH 9, current density of 60 A m–2, electrolysis time of 80 min, and [Al2(SO4)3] of 1.8 mg L–1. Under these operating conditions, turbidity, COD, and biochemical oxygen demand (BOD) removal efficiencies of 93.1%, 80.7%, and 89.7%, respectively, were obtained. The operating cost of the process was calculated at 0.9 USD per m³. The EF method combined with chemical coagulation was shown to be a suitable process for the treatment of effluent from the slaughter and processing of poultry.

Download Full-text

Electrooxidation of simulated wastewater containing pharmaceutical amoxicillin on thermally prepared IrO2/Ti

Mediterranean Journal of Chemistry ◽

10.13171/mjc02104071566ftaa ◽

2021 ◽

Vol 11 (2) ◽

pp. 172

Author(s):

Thiery Auguste Foffié Appia ◽

Lassiné Ouattara

Keyword(s):

Cyclic Voltammetry ◽

Reduction Rate ◽

Oxygen Demand ◽

Inorganic Ions ◽

Iridium Oxide ◽

Chloride Ions ◽

Preparative Electrolysis ◽

Experimental Conditions ◽

Cod Reduction ◽

Initial Ph

The electrooxidation of amoxicillin (AMX) on the iridium oxide electrode thermally prepared (400°C) has been investigated by cyclic voltammetry and preparative electrolysis. Physical characterization by Scanning Electron Microscopy (SEM) showed that the IrO2 electrode has a rough surface with pores' presence. In cyclic voltammetry, the oxidation of AMX occurs directly at the anode's surface or via the higher degree oxide of iridium oxide (IrO3). It is noted that the oxidation process of AMX can be controlled by diffusion combined with the phenomenon of adsorption. In preparative electrolysis, the effect of several parameters has been investigated. These are the current density, the support medium, the initial pH. The findings obtained show a weak degradation of amoxicillin. The Chemical Oxygen Demand (COD) reduction rate is less than 11% under our experimental conditions, indicating that the IrO2 electrode leads to the parent compound's conversion. Also, the degradation of the organic compound is favored in a very acidic medium.Furthermore, the effect of inorganic ions such as SO42-, PO43-, NO3-, Cl- was evaluated. Investigations show that these ions' effects are diverse, with COD reduction rates ranging from 2.47%; 2.68%; 7.7%; 16.41%, and 71.65%, respectively, in the absence and the presence of SO42-, PO43-, NO3-, Cl- ions. SO42- have virtually no effect on enhancing the degradation of amoxicillin. PO43- ions provide a slight improvement in amoxicillin degradation. As for nitrate ions, their influence is 2.31 times that of phosphate ions. Chloride ions improve the performance of the electrooxidation of amoxicillin on IrO2 very significantly. The presence of chloride ions makes it possible to go from 2928.35 (absence of inorganic ions) to 33.19 kWh per Kg of COD. This represents an energy gain of over 98%.

Download Full-text