The treatment of zinc-cyanide electroplating rinse water using an electrocoagulation process

2013 ◽  
Vol 68 (10) ◽  
pp. 2220-2227 ◽  
Author(s):  
Elif Senturk
Keyword(s):  
Electrode Material ◽  
Operating Time ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Operating Parameters ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Removal Efficiencies ◽  
Rinse Water ◽  
Electrode Connection

This paper investigates the treatment of zinc-cyanide electroplating rinse water using an electrocoagulation process (ECP). The effects of operating parameters such as electrode material, current density (2.5–40 A/m2), operating time (0–60 min), initial pH (5–12) and electrode connection mode (monopolar parallel (MP-P), monopolar series and bipolar series) on the ECP were evaluated to find the optimum operating conditions. At 20 A/m2, 60 min, the highest removal efficiencies were obtained with 85 and 99% for Fe and 64 and 33% for Al electrodes, for cyanide and zinc, respectively. The optimum operating conditions were found to be 30 A/m2 and 40 min, for the Fe electrode at the original pH (9.5) of the rinse water. Considering efficiency and economy, the MP-P connection mode was determined as the optimum connection mode.

scholarly journals Electrocoagulation for ammonium removal in Nam Son landfill leachate

2017 ◽  
Vol 33 (2) ◽  
Author(s):  
Thanh Son Le ◽  
Khải Cao Lê ◽  
Hà Thị Nguyễn ◽  
Linh Tuấn Đoàn ◽  
Anh Thị Đoàn
Keyword(s):  
Landfill Leachate ◽  
Operating Time ◽  
Operating Conditions ◽  
Current Intensity ◽  
Optimum Operating ◽  
Applied Current ◽  
Ammonium Removal ◽  
Treatment Performance ◽  
Iron Electrodes ◽  
Initial Ph

In this paper, an electrocoagulation reactor was set up to investigate the ammonium removal in Nam Son landfill leachate. The research focused on studying several factors that affect to the ammonium removal namely current intensity, operating time, initial pH and electrode materials. Mono-polar electrocoagulation reactor was conducted in a batch system with iron electrodes and 1.8 L leachate. The research indicated that current intensity and operating time are directly proportional with NH4+ treatment performance. When applied current increased from 1 to 4A, the NH4+ removal percentage went up from 14.03 to 24.99% after a 1 hour treatment. The effect of initial pH in range of 5 to 10 has showed that the best NH4+ treatment efficiency in neutral and mild alkaline conditions. It is noticeable that iron electrodes had higher NH4+ removal than aluminum one during nearly the first 40 min, however this trend has been reversed later with the advantage belonging to aluminum anode. The optimum operating conditions found are aluminum electrodes, applied current of 3A, electrolysis time of 60 min, raw pH of 8, resulting in NH4+ treatment performance of approximately 24%. As a result, the electrocoagulation method is not really effective in NH4+ removal and might be applied as a pre-treatment.

scholarly journals Removal of COD and BOD from biologically treated municipal wastewater by electrochemical treatment

2013 ◽  
Vol 5 (2) ◽  
pp. 475-481 ◽  
Author(s):  
Arun Kumar Sharma ◽  
A. K. Chopra
Keyword(s):  
Municipal Wastewater ◽  
Operating Cost ◽  
Operating Time ◽  
Sewage Treatment Plant ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Initial Ph ◽  
Treated Municipal Wastewater ◽  
Maximum Removal

The present investigation observed the effect of current density (CD), operating time (OT), inter electrode distance (IED), electrode area (EA), initial pH and settling time (ST) using Fe-Fe electrode combination on the removal of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) from biologically treated municipal wastewater (BTMW) of Sewage Treatment Plant (STP). The maximum removal of COD (92.35%) from BTMW was found with the optimum operating conditions of CD (2.82 A/m2), OT (40 mins.), IED (0.5 cm), EA (160 cm2), initial pH (7.5) and ST (60 min.), while the maximum removal of BOD (84.88%) was found with the ST (30 min.) at the same operating conditions. There was no need of pH adjustment of the BTMW during ET as the optimal removal efficiency was close to the pH of 7.5. Under optimal operating conditions, the operating cost was found to be 54.29 Rs./m3 / 1.08 US$/m3 in terms of the electrode consumption (78.48 x 10-5 kg Al/m3 ) and energy consumption (108.48 Kwh/m3).

scholarly journals Optimization of electrocoagulation process to treat biologically pretreated bagasse effluent

2014 ◽  
Vol 79 (5) ◽  
pp. 613-626 ◽  
Author(s):  
K. Thirugnanasambandham ◽  
V. Sivakumar ◽  
Maran Prakash
Keyword(s):  
Response Surface ◽  
Three Dimensional ◽  
Oxygen Demand ◽  
Electrical Energy ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Applied Current ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Pretreated Bagasse

The main objective of the present study was to investigate the efficiency of electrocoagulation process as a post-treatment to treat biologically pretreated bagasse effluent using iron electrodes. The removal of chemical oxygen demand (COD) and total suspended solids (TSS) were studied under different operating conditions such as amount of dilution, initial pH, applied current and electrolyte dose by using response surface methodology (RSM) coupled with four-factor three-level Box-Behnken experimental design (BBD). The experimental results were analyzed by Pareto analysis of variance (ANOVA) and second order polynomial mathematical models were developed with high correlation of efficiency (R2) for COD, TSS removal and electrical energy consumption (EEC). The individual and combined effect of variables on responses was studied using three dimensional response surface plots. Under the optimum operating conditions, such as amount of dilution at 30 %, initial pH of 6.5, applied current of 8 mA cm-2 and electrolyte dose of 740 mg l-1 shows the higher removal efficiency of COD (98 %) and TSS (93 %) with EEC of 2.40 Wh, which were confirmed by validation experiments.

scholarly journals Efficiency of aluminum and iron electrodes in removal of colour, turbidity and total suspended solid from biologically treated municipal wastewater

2015 ◽  
Vol 7 (2) ◽  
pp. 799-805
Author(s):  
Arun Kumar Sharma ◽  
A.K. Chopra
Keyword(s):  
Municipal Wastewater ◽  
Operating Time ◽  
Total Suspended Solid ◽  
Suspended Solid ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Electrode Consumption ◽  
Electrode Combination ◽  
Initial Ph ◽  
Treated Municipal Wastewater

The present investigation was undertaken to observe the effect of different combinations of aluminium and iron (Al-Al, Al-Fe, Fe-Fe and Fe-Al) electrodes on the removal of colour, turbidity (TD) and total suspended solids (TSS) of biologically treated municipal wastewater ( BTMW) using applied potential (V), operating time (OT) and initial pH. The maximum removal of colour (98.7 %) and TSS (96.89 %) was found with the use of Al-Al combination with optimum operating conditions (Voltage: 40 V; OT: 40 mins.; IED: 1.0 cm; EA: 160 cm2; initial pH: 7.5 and ST: 30 mins). It was interesting to note that TD of BTMW was completely removed at these optimal operating conditions. The economic evaluation of electrode combinations was observed to be in the order of Fe-Al (1.17 US $/m3)> Al-Fe (1.11 US $/m3)> Fe-Fe (1.08 US $/m3) >Al-Al (1.01 US $/m3) in terms of energy and electrode consumption. Thus, the BTMW can be effectively treated with the Al-Al electrode combination in comparison to other electrode combinations (Al-Fe , Fe-Fe and Fe-Al).

scholarly journals Removal of arsenate by electrocoagulation reactor using aluminum ball anode electrodes

2018 ◽  
Vol 13 (4) ◽  
pp. 753-763 ◽  
Author(s):  
A. Y. Gören ◽  
M. S. Öncel ◽  
E. Demirbas ◽  
E. Şık ◽  
M. Kobya
Keyword(s):  
Removal Efficiency ◽  
Operating Time ◽  
Operating Conditions ◽  
Column Height ◽  
Quadratic Model ◽  
Optimum Operating ◽  
Airflow Rate ◽  
Statistical Experimental Design ◽  
Applied Current ◽  
Initial Ph

Abstract The aim of this research was to remove arsenate (As(V)) from groundwater using an air-injected electrocoagulation (EC) reactor with aluminum (Al) ball anodes. The effects of seven operating variables – initial pH, applied current (i), operating time (tEC), initial As(V) concentration (Co), Al ball anode diameter (dp), reactor column height (h), and airflow rate (Qair) were investigated with a Box-Behnken statistical experimental design. ANOVA results from the quadratic model equations indicated that the model fitted very well with the experimental data for the responses, which were removal efficiency, operating cost (OC), As(V) adsorption capacity, and effluent concentration (R2 ≥ 0.87). The most effective parameters were applied current, operating time, and anode height for As(V) removal efficiency in the EC reactor, while initial pH, Al anode diameter, and air flow rate had limited effect on removal. The model predicted a residual As(V) concentration below 10 μg/L under the optimum operating conditions (pH 7.03, 0.29 A, 10.5 min, dp 7.5 mm, 613.4 μg/L, h 5.1 cm, and Qair 6.4 L/min). The maximum As(V) removal efficiency and minimum OC in the EC process were almost 99% and 0.442 $/m3, respectively.

scholarly journals Effect of some effective parameters on COD Removal from Nam Son Landfill Leachate by electrocoagulation

2017 ◽  
Vol 55 (5) ◽  
pp. 540
Author(s):  
Son Thanh Le ◽  
Khai Cao Le ◽  
Linh Tuan Doan ◽  
Anh Thi Doan
Keyword(s):  
Operating Time ◽  
Operating Conditions ◽  
Cod Removal ◽  
Current Intensity ◽  
Optimum Operating ◽  
Electrolysis Time ◽  
Leachate Treatment ◽  
Treatment Performance ◽  
Iron Electrodes ◽  
Removal Efficiencies

Leachate becomes ahead of wastewaters as being the most difficult to treat due to its complex and widely variable composition. In this research, the leachate treatment performance by electrocoagulation (EC) was studied. The samples of leachate were taken from Nam Son landfill in Hanoi. The effects of factors namely current intensity, electrolysis time, initial pH and anode materials on the EC performance were investigated via chemical oxygen demand (COD) removal efficiencies. The input leachate properties were obtained as COD, NH4+ and pH in the range of around 6247 ± 295, 1270 ± 38 mg/l and 8 ± 0.1, respectively. Mono-polar electrocoagulation unit was carried out in a batch system for leachate treatment with iron electrodes and approximately 1.8 litter of leachate. Firstly, with the increase in current (1 to 4A), the COD removal efficiencies increased from 50.00 to 78.57% (pH = 8 and operating time = 40 min). Secondly, by the increase in operating time, the treatment performance also went up significantly in first 40 min, then nearly level-off at above 73 % (pH=8, current intensity = 3A). In addition, the effect of pH in range of 5 to 10 on the electrocoagulation process was studied and showed the highest treatment efficiencies in neutral and mild alkaline medium, especially between 6 < pH < 8. Finally, the electrode materials made of iron and aluminum was investigated and the result indicated that when the iron anodes were replaced by aluminum, the COD removal efficiency experienced a considerable decline, from 70 to 37.93% (pH = 8 and operating time = 40 min). In combination of all experiments, the optimum operating conditions were achieved as iron electrodes, current intensity of 3A, electrolysis time of 40 min, the raw pH with iron electrodes, resulting the maximum COD removal efficiencies of 73.21%. As a result, the electrocoagulation can be applied to leachate pre-treatment.

scholarly journals Influence of operating conditions on the electrolytic treatment for the removal of color, TSS, hardness and alkalinity using Al-Al electrode combination

2014 ◽  
Vol 6 (1) ◽  
pp. 279-285 ◽  
Author(s):  
Arun Kumar Sharma ◽  
A. K. Chopra
Keyword(s):  
Municipal Wastewater ◽  
Operating Cost ◽  
Operating Time ◽  
Sewage Treatment Plant ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Electrode Combination ◽  
Initial Ph ◽  
Maximum Removal ◽  
Electrolytic Treatment

The present investigation observed the effect of current density (CD), operating time (OT), inter electrode distance (IED), electrode area (EA), initial pH and settling time (ST) using Al-Al electrode combination on the removal of color, total suspended solids (TSS), hardness (HR) and alkalinity (ALK) from biologically treated municipal wastewater (BTMW) of Sewage Treatment Plant (STP), Jagjeetpur, Haridwar, India. The maximum removal of color (99.86%), TSS (98.7%), HR (78.9%) and ALK (43.69 %) from BTMW was found with the optimum operating conditions of CD (2.65 A/m2), OT (40 mins.), IED (0.5 cm), EA (160 cm2), initial pH (7.5) and ST (60 min.). However, the maximum removal of ALK was found with the optimum operating conditions of CD (1.68 A/m2), OT (40 mins.), IED (1.0 cm), EA (80 cm2), initial pH (7.5) and ST (90 min.) The electrolytic treatment ( ET) brought down the concentration of HR and ALK to the desirable limit of the BIS standards of drinking water. There was no need of pH adjustment of the BTMW during ET as the optimal removal efficiency was close to the pH of 7.5. Under optimal operating conditions, the operating cost was found to be 1.01 $/m3 in terms of the electrode consumption (23.71x 10-5 kg Al/m3) and energy consumption (101.76 Kwh/m3). The study revealed that BTMW can be effectively treated with the Al-Al electrode combination for color, TSS, HR and ALK removal.

Effects of operational parameters on defluoridation efficiency using electrocoagulation process

2011 ◽  
Vol 6 (1) ◽  
Author(s):  
M. Behbahani ◽  
M.R. Alavi Moghaddam ◽  
M. Arami
Keyword(s):  
Reaction Time ◽  
Anode Material ◽  
Removal Efficiency ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Operational Parameters ◽  
Applied Current ◽  
Initial Ph ◽  
Electrocoagulation Process ◽  
Electrode Connection

The aim of this study is to examine the effect of operational parameters on fluoride removal using electrocoagulation method. For this purpose, various operational parameters including initial pH, initial fluoride concentration, applied current, reaction time, electrode connection mode, anode material, electrolyte salt, electrolyte concentration, number of electrodes and interelectrode distance were investigated. The highest defluoridation efficiency achieved at initial pH 6. In the case of initial fluoride concentration, maximum removal efficiency (98.5%) obtained at concentration of 25mg/l. The increase of applied current and reaction time improved defluoridation efficiency up to 99%. The difference of fluoride removal efficiencies between monopolar and bipolar series and monopolar parallel were significant, especially at reaction time of 5 min. When aluminum used as anode material, higher removal efficiency (98.5%) achieved compared to that of iron anode (67.7%). The best electrolyte salt was NaCl with the maximum defluoridation efficiency of 98.5% compared to KNO3 and Na2SO4. The increase of NaCl had no effect on defluoridation efficiency. Number of electrodes had little effect on the amounts of Al3+ ions released in the solution and as a result defluoridation efficiency. Almost the same fluoride removal efficiency obtained for different interelectrode distances.

Electrochemical treatment of Baker's yeast wastewater containing melanoidin: optimization through response surface methodology

2012 ◽  
Vol 65 (12) ◽  
pp. 2183-2190 ◽  
Author(s):  
E. Gengec ◽  
M. Kobya ◽  
E. Demirbas ◽  
A. Akyol ◽  
K. Oktor
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Current Density ◽  
Baker’S Yeast ◽  
Optimum Operating ◽  
Operating Parameters ◽  
Baker's Yeast ◽  
Toc Removal ◽  
Removal Efficiencies ◽  
Yeast Wastewater

Effluents from Baker's yeast production plant contain a high percentage of color and a large amount of organic load. In the present study, Baker's yeast wastewater (BYW) is treated with the electrocoagulation (EC) process using Al electrodes. Operating parameters (pH, current density, color intensity and operating time) are optimized by response surface methodology (RSM). Quadratic models are developed for the responses which are removal efficiencies of color, chemical oxygen demand (COD) and total organic carbon (TOC) and operating cost (OC). Optimum operating parameters and responses are determined as initial pH 5.2, current density of 61.3 A/m2 and operation time of 33 min, and 71% of color, 24% of COD, 24% of TOC removal efficiencies and OC of 0.869 €/m3, respectively. The quadratic model fits for all responses very well with R2 (&gt;0.95). This paper clearly shows that RSM is able to optimize the operating parameters to maximize the color, COD and TOC removal efficiencies and minimize the OC.

scholarly journals Fixed bed utilization for the isolation of xylene vapor: Kinetics and optimization using response surface methodology and artificial neural network

2020 ◽  
Vol 26 (2) ◽  
pp. 200105-0
Author(s):  
Kaushal Naresh Gupta ◽  
Rahul Kumar
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Flow Rate ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Operating Parameters ◽  
Bed Height ◽  
Artificial Neural

This paper discusses the isolation of xylene vapor through adsorption using granular activated carbon as an adsorbent. The operating parameters investigated were bed height, inlet xylene concentration and flow rate, their influence on the percentage utilization of the adsorbent bed up to the breakthrough was found out. Mathematical modeling of experimental data was then performed by employing a response surface methodology (RSM) technique to obtain a set of optimum operating conditions to achieve maximum percentage utilization of bed till breakthrough. A fairly high value of R2 (0.993) asserted the proposed polynomial equation’s validity. ANOVA results indicated the model to be highly significant with respect to operating parameters studied. A maximum of 76.1% utilization of adsorbent bed was found out at a bed height of 0.025 m, inlet xylene concentration of 6,200 ppm and a gas flow rate of 25 mL.min-1. Furthermore, the artificial neural network (ANN) was also employed to compute the percentage utilization of the adsorbent bed. A comparison between RSM and ANN divulged the performance of the latter (R2 = 0.99907) to be slightly better. Out of various kinetic models studied, the Yoon-Nelson model established its appropriateness in anticipating the breakthrough curves.

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