scholarly journals Treatment of vinegar industry wastewater by electrocoagulation with monopolar aluminum and iron electrodes and toxicity evaluation

2018 ◽  
Vol 78 (12) ◽  
pp. 2542-2552 ◽  
Author(s):  
Seval Yılmaz ◽  
Emine Esra Gerek ◽  
Yusuf Yavuz ◽  
Ali Savaş Koparal
Keyword(s):  
Removal Efficiency ◽  
Current Density ◽  
Oxygen Demand ◽  
Electrical Current ◽  
Cod Removal ◽  
Toxicity Tests ◽  
Polyaluminum Chloride ◽  
Chemical Complexity ◽  
Iron Electrodes ◽  
Industry Wastewater

Abstract We present electrocoagulation (EC) treatment results of vinegar industry wastewater (VIW) using parallel plate aluminum and iron electrodes, and analyze the toxicity of the treatment processes. Due to the chemical complexity of vinegar production wastewater, several parameters are expected to alter the treatment efficiency. Particularly, current density, initial pH, Na2SO4 as support electrolyte, polyaluminum chloride (PAC) and kerafloc are investigated for their effects on chemical oxygen demand (COD) removal. Following several treatment experiments with real wastewater samples, aluminum-plate electrodes were able to reach to a removal efficiency of 90.91% at pH 4, 10 mg/L PAC and an electrical current density of 20.00 mA/cm2, whereas iron-plate electrodes reached to a removal efficiency of 93.60% at pH 9, 22.50 mA/cm2 current density. Although EC processes reduce COD, the usefulness of the system may not be assessed without considering the resultant toxicity. For this purpose, microtox toxicity tests were carried out for the highest COD removal case. It was observed that the process reduces toxicity, as well as the COD. Consequently, it is concluded that EC with aluminum and iron electrodes is COD removal-wise and toxicity reduction-wise a plausible method for treatment of VIW, which has high organic pollutants.

Simultaneous decolorization of binary mixture of Reactive Yellow and Acid Violet from wastewaters by electrocoagulation

2011 ◽  
Vol 63 (8) ◽  
pp. 1644-1650 ◽  
Author(s):  
Can Serkan Keskin ◽  
Abdil Özdemir ◽  
İ. Ayhan Şengil
Keyword(s):  
Removal Efficiency ◽  
Current Density ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Time Duration ◽  
Synthetic Dye ◽  
Nacl Concentration ◽  
Optimum Ph ◽  
Dyestuff Wastewater ◽  
Acid Violet

Dyes are common pollutants in a large variety of industrial wastewaters, and the treatment of these wastes has been extensively studied by coagulation. For the removal of pollutants from the wastewaters, different techniques have been used and electrocougulation is one of the widely used methods. This process is very effective in removing organic pollutants including dyestuff wastewater. The purposes of this study were to investigate the effects of the operating parameters, such as current density, electrolyte concentration, dyestuff concentration, and pH of solution on decolorization and chemical oxygen demand (COD) removal of wastewater containing two different dyes in same solution by direct current electrocoagulation. The amount of dye removed was found by application of first derivative spectrophotometric method to the synthetic dye mixtures. In this work synthetic dye mixture which include C.I. Reactive Yellow 145 (RY145) and C.I. Acid Violet 90 (AV 90) were used for electrocougulation (EC) process with iron electrodes. In the presence of both dye molecules, the optimum pH was found to be 4, optimum NaCl concentration was 3000 mg/L and optimum current density was 5.56 mA/cm2. Under these conditions in the case of 100 mg/L−1 each dye concentration at 20°C and 3 cm interelectro distance the color removal efficiency was reached 97.7% for AV 90 and 97.1% for RY145 in 10 minutes time duration. Dye concentration dependent highest COD removal efficiency was measured as 82% around at 100 mg/L dye concentration.

scholarly journals Modeling and Optimization of COD Removal from Cold Meat Industry Wastewater by Electrocoagulation Using Computational Techniques

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1139 ◽  
Author(s):  
Juan Morales-Rivera ◽  
Belkis Sulbarán-Rangel ◽  
Kelly Joel Gurubel-Tun ◽  
Jorge del Real-Olvera ◽  
Virgilio Zúñiga-Grajeda
Keyword(s):  
Current Density ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Cod Removal ◽  
Computational Techniques ◽  
Meat Industry ◽  
Control Parameters ◽  
Operational Cost ◽  
Box Behnken Design ◽  
Industry Wastewater

In this paper, electrocoagulation (EC) treatment for the removal of chemical oxygen demand (COD) from cold meat industry wastewater is modeled and optimized using computational techniques. Methods such as artificial neural networks (ANNs) and response surface methodology (RSM), based on the Box–Behnken design using three levels, were employed to calculate the best control parameters for pH (5–9), current density (2–6 mA/cm2) and EC time (20–60 min). Analysis of variance (ANOVA) and 3D graphs revealed that pH and current density are the main parameters used for depicting the EC process. The developed models successfully describe the process with a correlation coefficient of R2 = 0.96 for RSM and R2 = 0.99 for ANN. The models obtained were optimized applying the moth-flame optimization (MFO) algorithm to find the best operating conditions for COD removal. ANN-MFO was used and showed superior COD removal (92.91%) under conditions of pH = 8.9, current density = 6.6 mA/cm2 and an EC time of 38.62 min. The energy consumption with these optimal conditions was 6.92 kWh/m3, with an operational cost of $3.14 (USD)/m3. These results suggest that the proposed computational model can be used to obtain more effective and economical treatments for this type of effluent.

Optimization of paper mill industry wastewater treatment by electrocoagulation and electro-Fenton processes using response surface methodology

2017 ◽  
Vol 76 (8) ◽  
pp. 2015-2031 ◽  
Author(s):  
Senem Yazici Guvenc ◽  
Hanife Sari Erkan ◽  
Gamze Varank ◽  
Mehmet Sinan Bilgili ◽  
Guleda Onkal Engin
Keyword(s):  
Response Surface Methodology ◽  
Wastewater Treatment ◽  
Response Surface ◽  
Current Density ◽  
Desirability Function ◽  
Oxygen Demand ◽  
Paper Mill ◽  
Cod Removal ◽  
Molar Ratio ◽  
Industry Wastewater

This study deals with chemical oxygen demand (COD), phenol and Ca+2 removal from paper mill industry wastewater by electrocoagulation (EC) and electro-Fenton (EF) processes. A response surface methodology (RSM) approach was employed to evaluate the effects and interactions of the process variables and to optimize the performance of both processes. Significant quadratic polynomial models were obtained (R2 = 0.959, R2 = 0.993 and R2 = 0.969 for COD, phenol and Ca+2 removal, respectively, for EC and R2 = 0.936, R2 = 0.934 and R2 = 0.890 for COD, phenol and Ca+2 removal, respectively). Numerical optimization based on desirability function was employed; in a 27.55 min trial, 34.7% of COD removal was achieved at pH 9 and current density 96 mA/cm2 for EC, whereas in a 30 min trial, 74.31% of COD removal was achieved at pH 2 and current density 96 mA/cm2 and H2O2/COD molar ratio 2.0 for EF. The operating costs were calculated to be 6.44 €/m3 for EC and 7.02 €/m3 for EF depending on energy and electrode consumption at optimum conditions. The results indicate that the RSM is suitable for the design and optimization of both of the processes. However, EF process was a more effective technology for paper mill industry wastewater treatment as compared with EC.

Treatment of dairy wastewaters by electrocoagulation using iron electrodesTraitement des eaux résiduaires d'une laiterie par électrocoagulation avec des électrodes de fer

2014 ◽  
Vol 50 (2) ◽  
pp. 198-209 ◽  
Author(s):  
Malika Aoudjehane ◽  
Mohamed Elghazali Benatallah
Keyword(s):  
Electrical Conductivity ◽  
Removal Efficiency ◽  
Current Density ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Electrolysis Time ◽  
Electrode Consumption ◽  
Treatment Conditions ◽  
Consumption Energy ◽  
Optimal Efficiency

A procedure of electrocoagulation (EC) using iron electrodes has been used for the treatment of the wastewaters produced by the Beni-Tamou dairy in Algeria. The effect of the operating conditions, such as the current intensity, the electrolysis time, the pH of the solution and the electrical conductivity, on the removal efficiency of chemical oxygen demand (COD) and the total suspended solids (TSS) has been studied. An inter-electrode distance of 1 cm has been maintained constant during the tests. It has been found that an increase in electrolysis time and current density improved the treatment significantly, albeit with a greater consumption of energy as well as an increased electrode consumption. The results of the electrocoagulation treatment under various operating conditions show that the optimal efficiency has been obtained under the following conditions: 60 minutes of electrolysis, a current density of 200 A/m2, a pH 8, an electrical conductivity of 4.72 mS/cm and a consumption energy of 13.57 kWh/m3. Under these conditions, the removal efficiency for the COD and TSS parameters is 93.26 and 99.3%, respectively. The optimal treatment conditions of dairy wastewaters have resulted in final COD and TSS concentrations of 41.5 and 27 mg/L, respectively, values that are conform to industrial liquid effluents discharge norms.

COD removal efficiency and mechanism of HMBR in high volumetric loading for ship domestic sewage treatment

2016 ◽  
Vol 74 (7) ◽  
pp. 1509-1517 ◽  
Author(s):  
Linan Zhu ◽  
Hailing He ◽  
Chunli Wang
Keyword(s):  
Removal Efficiency ◽  
Removal Rate ◽  
Sewage Treatment ◽  
Oxygen Demand ◽  
Domestic Sewage ◽  
Cod Removal ◽  
Aeration Tank ◽  
Remarkable Effect ◽  
Cod Removal Efficiency ◽  
Volumetric Loading

The hybrid membrane bioreactor (HMBR) has been applied in ship domestic sewage treatment under high volumetric loading for ship space saving. The mechanism and influence factors on the efficiency, including hydraulic retention time (HRT), dissolved oxygen (DO) of chemical oxygen demand (COD) removal were investigated. The HMBR's average COD removal rate was up to 95.13% on volumetric loading of 2.4 kgCOD/(m3•d) and the COD concentration in the effluent was 48.5 mg/L, far below the International Maritime Organization (IMO) discharge standard of 125 mg/L. DO had a more remarkable effect on the COD removal efficiency than HRT. In addition, HMBR revealed an excellent capability of resisting organics loading impact. Within the range of volumetric loading of 0.72 to 4.8 kg COD/(m3•d), the effluent COD concentration satisfied the discharge requirement of IMO. It was found that the organics degradation in the aeration tank followed the first-order reaction, with obtained kinetic parameters of vmax (2.79 d−1) and Ks (395 mg/L). The original finding of this study had shown the effectiveness of HMBR in organic contaminant degradation at high substrate concentration, which can be used as guidance in the full scale of the design, operation and maintenance of ship domestic sewage treatment devices.

Removal of phenol from steel wastewater by combined electrocoagulation with photo-Fenton

2018 ◽  
Vol 78 (6) ◽  
pp. 1260-1267 ◽  
Author(s):  
Mohammad Malakootian ◽  
Mohammad Reza Heidari
Keyword(s):  
Reaction Time ◽  
Removal Efficiency ◽  
Current Density ◽  
Steel Industry ◽  
High Efficiency ◽  
Oxygen Demand ◽  
Optimal Conditions ◽  
Suitable Alternative ◽  
Steel Mills ◽  
Real Wastewater

Abstract Phenol and its derivatives are available in various industries such as refineries, coking plants, steel mills, drugs, pesticides, paints, plastics, explosives and herbicides industries. This substance is carcinogenic and highly toxic to humans. The purpose of the study was to investigate the removal of phenol from wastewater of the steel industry using the electrocoagulation–photo-Fenton (EC-PF) process. Phenol and chemical oxygen demand (COD) removal efficiency were investigated using the parameters pH, Fe2+/H2O2, reaction time and current density. The highest removal efficiency rates of phenol and COD were 100 and 98%, respectively, for real wastewater under optimal conditions of pH = 4, current density = 1.5 mA/cm2, Fe2+/H2O2 = 1.5 and reaction time of 25 min. Combination of the two effective methods for the removal of phenol and COD, photocatalytic electrocoagulation photo-Fenton process is a suitable alternative for the removal of organic pollutants in industry wastewater because of the low consumption of chemicals, absence of sludge and other side products, and its high efficiency.

Biological wastewater treatment for removal of polymeric resins in UASB reactor: influence of oxygen

2008 ◽  
Vol 57 (7) ◽  
pp. 1047-1052 ◽  
Author(s):  
U. Durán ◽  
O. Monroy ◽  
J. Gómez ◽  
F. Ramírez
Keyword(s):  
Acrylic Acid ◽  
Vinyl Acetate ◽  
Removal Efficiency ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Uasb Reactor ◽  
Cod Removal Efficiency ◽  
Consumption Rates ◽  
Polymeric Resins

The biological elimination of polymeric resins compounds (PRC) such as acrylic acid and their esters, vinyl acetate and styrene under methanogenic and oxygen-limited methanogenesis conditions was evaluated. Two UASB reactors (A and B) were used and the removal of the organic matter was studied in four stages. Reactor A was used as methanogenic control during the study. Initially both reactors were operated under methanogenic conditions. From the second stage reactor B was fed with 0.6 and 1 mg/L·d of oxygen (O2). Reactor A had diminution in chemical oxygen demand (COD) removal efficiency from 75±4% to 37±5%, by the increase of PRC loading rate from 750 to 1125 mg COD/L·d. In this reactor there was no styrene elimination. In reactor B the COD removal efficiency was between 73±5% and 80±2%, even with the addition of O2 and increase of the PRC loading rate, owing to oxygen being used in the partial oxidation of these compounds. In this reactor the yields were modified from 0.56 to 0.40 for CH4 and from 0.31 to 0.60 for CO2. The O2 in low concentrations increased 40.7% the consumption rates of acrylic acid, methyl acrylate and vinyl acetate, allowing styrene consumption with a rate of 0.103 g/L·d. Batch cultures demonstrated that under methanogenic and oxygen-limited methanogenesis conditions, the glucose was not used as an electron acceptor in the elimination of PRC.

scholarly journals Innovative Effluent Capture and Evacuation Device that Increases COD Removal Efficiency in Subsurface Flow Wetlands

Processes ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 418 ◽  
Author(s):  
Pedro Cisterna-Osorio ◽  
Verónica Lazcano-Castro ◽  
Gisela Silva-Vasquez ◽  
Mauricio Llanos-Baeza ◽  
Ignacio Fuentes-Ortega
Keyword(s):  
Chemical Oxygen Demand ◽  
Removal Efficiency ◽  
Subsurface Flow ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Cod Removal ◽  
Discharge Device ◽  
The Impact ◽  
Real Scale ◽  
Conventional Device

The objective of this work is to evaluate the impact of innovative modifications made to conventional effluent capture and discharge devices used in subsurface flow wetlands (SSFW). The main modifications that have been developed extend the influence of the capture and discharge device in such a way that the SSFW width and height are fully covered. This improved innovative device was applied and evaluated in two subsurface flow wetlands, one on a pilot scale and one on a real scale. To evaluate the impact of the innovative device with respect to the conventional one in the operational functioning of subsurface flow wetlands, the elimination of chemical oxygen demand (COD) was measured and compared. The results show that for the innovative device, the COD removal was 10% higher than for the conventional device, confirming the validity and effectiveness of the modifications implemented in the effluent capture and discharge devices used in SSFW.

scholarly journals Batch Electrocoagulation Treatment of Peat Water in Sarawak with Galvanized Iron Electrodes

2020 ◽  
Vol 997 ◽  
pp. 127-138
Author(s):  
Nazzeri Abdul Rahman ◽  
Nur Afifah Tomiran ◽  
Aiman Hakim Hashim
Keyword(s):  
Organic Carbon ◽  
Total Organic Carbon ◽  
Humic Acids ◽  
Current Density ◽  
Treatment Time ◽  
Oxygen Demand ◽  
Experimental Tests ◽  
Iron Electrodes ◽  
Filtration System ◽  
Standard Limit

Peat water is an abundant water resource in Sarawak where some of the coastal areas in Sarawak still utilize peat water for domestic usage. Peat water contains natural organic matters especially humic substances which include humic acids. Humic acids contribute to the brown color of peat water and can cause diseases such as stomach cancer, blackfoot disease and etc. if consumed by human. Electrocoagulation is an alternative to conventional water treatment methods which have the advantages of being environmental friendly, minimal sludge production and no addition of chemical substances. The aims of this study are to fabricate a desktop scale electrocoagulation system with galvanised iron electrodes and to investigate the effects of the operating parameters such as inter-electrode distance, applied current density, number of electrodes, and treatment time on peat water in the system. The performance of batch electrocoagulation system in term of their removal efficiency of several parameters such as total organic carbon (TOC), chemical oxygen demand (COD), color and turbidity are evaluated. Through experimental tests conducted, this system successfully removes 98.44% of COD, 92.02% of TOC, 97.92% of turbidity and 99.91% of color by using galvanized iron as an electrode at current density of 25 A/m2in 30 minutes with 10 galvanized iron electrodes. Despite the fact that there is a small amount of iron ions and zinc ions remained in the treated peat water which are 0.001mg/l and 0.0442mg/l respectively, these concentrations are far below the standard limits imposed by Malaysia Ministry of Health (MOH). Generally, all the parameters studied meet the standard limit imposed by MOH except for total organic carbon. This is particularly due to the improper filtration system adopted in this study. The total operating costs for 252 in 30 minutes treatment time of 10 electrode plates is RM 8.75 per . Overall, the study have successfully designed a batch electrocoagulation system to treat peat water by using galvanized iron for domestic usage.

scholarly journals Energy capture and nutrients removal enhancement through a stacked constructed wetland incorporated with microbial fuel cell

2017 ◽  
Vol 76 (1) ◽  
pp. 28-34 ◽  
Author(s):  
Lei Xu ◽  
Yaqian Zhao ◽  
Tongyue Wang ◽  
Ranbin Liu ◽  
Fei Gao
Keyword(s):  
Fuel Cell ◽  
Microbial Fuel Cell ◽  
Removal Efficiency ◽  
Oxygen Demand ◽  
Open Circuit ◽  
Cod Removal ◽  
Electrical Performance ◽  
Electricity Production ◽  
Performance Reduction ◽  
Tiered System

To improve the sustainability of constructed wetlands (CWs), a novel tiered wetland system integrated with a microbial fuel cell (MFC) was developed in this study. Compared to the single stage CW, chemical oxygen demand (COD) removal efficiency was improved from 83.2% to 88.7%. More significantly, this tiered system significantly enhanced total nitrogen removal efficiency (an increase from 53.1% to 75.4%). In terms of MFC integration, a gradually decreased performance in electricity production was observed during its 3 months of operation (the voltage dropped from nearly 600 mV to less than 300 mV), which resulted in a reduction of power density from around 2 W/m3 to less than 0.5 W/m3. The deterioration in performance of the air-cathode is the main reason behind this, since the electrode potential of the cathode under open circuit reduced from 348.5 mV to 49.5 mV while the anode potential kept constant at around −400 mV. However, in spite of its electrical performance reduction, it was proved that MFC integration enhanced COD removal and the nitrification process. Further work is needed to improve the stability and feasibility of this new system.

Sign in / Sign up

Export Citation Format

Share Document