scholarly journals Investigating the Electrocoagulation Treatment of Landfill Leachate by Iron/Graphite Electrodes: Process Parameters and Efficacy Assessment

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 205
Author(s):  
Tahereh Rookesh ◽  
Mohammad Reza Samaei ◽  
Saeed Yousefinejad ◽  
Hassan Hashemi ◽  
Zahra Derakhshan ◽  
...  

Electrocoagulation is a widely used method for treating leachate since it is cost effective and eco-friendly. In the present study, the electrocoagulation process was employed to remove chemical oxygen demand (COD), NH4+, total dissolved solids (TDS), total suspended solids (TSS), turbidity, and color from landfill leachate. At first, lime was used as a pretreatment, then the Fe/Gr and Ti/PbO2/steel electrodes were used, and the optimum electrode was selected. Afterwards, the effects of some variables, including pH, current density, temperature, the inter-electrode distance, and the type of electrolyte were investigated. Results showed that COD, NH4+, TSS, TDS, electrical conductivity (EC), turbidity, color, and pH of effluent pretreatment chemical reached 22,371, 385, 884, 21,820 (mg/L), 13.8 (ms/cm3), 1355 (NTU), 8500 (TCU) and 10, respectively (the removal efficiency was 0, 20.37, 32.4, 61.99, 59.18, and 56.6 percent). With the Fe/Gr electrode, the optimal condition was observed as follows: pH of 7.5, current density of 64 mA/cm2, inter-electrode distance was equal to 1.5 cm, temperature at 20 °C, and retention time 2–4 h. Overall, the electrocoagulation with the Fe/Gr electrode was a suitable technology for landfill leachate treatment due to its effectiveness for the removal of both COD and NH4+, with advantageous performance indicators.

2019 ◽  
Vol 80 (3) ◽  
pp. 458-465 ◽  
Author(s):  
Ahmed Samir Naje ◽  
Mohammed A. Ajeel ◽  
Isam Mohamad Ali ◽  
Hussein A. M. Al-Zubaidi ◽  
Peter Adeniyi Alaba

Abstract In this work, landfill leachate treatment by electrocoagulation process with a novel rotating anode reactor was studied. The influence of rotating anode speed on the removal efficiency of chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS) of raw landfill leachate was investigated. The influence of operating parameters like leachate pH, leachate temperature, current, and inter-distance between the cathode rings and anode impellers on the electrocoagulation performance were also investigated. The results revealed the optimum rotating speed is 150 rpm and increasing the rotating speed above this value led to reducing process performance. The leachate electrocoagulation treatment process favors the neutral medium and the treatment performance increases with increasing current intensity. Furthermore, the electrocoagulation treatment performance improves with increasing leachate temperature. However, the performance reduces with increasing inter-electrode distance.


2017 ◽  
Vol 76 (11) ◽  
pp. 2907-2917 ◽  
Author(s):  
Aysenur Ogedey ◽  
Mehtap Tanyol

Abstract Leachate is the most difficult wastewater to be treated due to its complex content and high pollution release. For this reason, since it is not possible to be treated with a single process, a pre-treatment is needed. In the present study, a batch electrocoagulation reactor containing aluminum and iron electrodes was used to reduce chemical oxygen demand (COD) from landfill leachate (Tunceli, Turkey). Optimization of COD elimination was carried out with response surface methodology to describe the interaction effect of four main process independent parameters (current density, inter-electrode distance, pH and time of electrolysis). The optimum current density, inter-electrode distance, pH and time of electrolysis for maximum COD removal (43%) were found to be 19.42 mA/m2, 0.96 cm, 7.23 and 67.64 min, respectively. The results shown that the electrocoagulation process can be used as a pre-treatment step for leachate.


2017 ◽  
Vol 77 (1) ◽  
pp. 177-186 ◽  
Author(s):  
Mehtap Tanyol ◽  
Aysenur Ogedey ◽  
Ensar Oguz

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.


The present research work mainly deals with the removal percentage of Color and Chemical Oxygen Demand (COD) on landfill leachate by using electrocoagulation (EC) process. An EC process was carried out with an aluminium electrode and it act as both anode and cathode. The study mainly targets the factors affecting on electrode material, electrolysis time, initial pH, applied voltage, inter-electrode distance. The experimental result reveals that there was raise in BOD/COD ratio from 0.11 to 0.66 and the maximum percentage removal achieved were COD and Color 78.4% and 77.0% respectively. The optimum inter-electrode distance 1cm with electrode surface area 35 cm2 and optimum electrolysis time of 90 min at optimum applied voltage 10V, stirring speed 250 rpm and pH is 9.3. These results showed that the EC process is appropriate and well-organized approach for the landfill leachate treatment.


2020 ◽  
Vol 8 (5) ◽  
pp. 104368
Author(s):  
Neanderson Galvão ◽  
Jeanette Beber de Souza ◽  
Carlos Magno de Sousa Vidal

Author(s):  
Siti Nor Farhana Zakaria

Landfill leachate is a hazardous pollutant generated from a landfill site. Discharge of landfill leachate has caused a major contamination to the environment and detrimental to human health. This chapter introduces an alternative method to treat recalcitrant pollutant in leachate by using ozonation with catalyst. The production of hydroxyl radical in ozonation was not enough to oxidize complex molecular structure in the leachate. Theoretically, the addition of catalyst enhances the capacity of radical and accelerates the chemical reaction. The effectiveness of ozonation with Fenton (O3/Fenton), hydrogen peroxide (O3/H2O2), and zirconium tetrachloride (O3/ZrCl4) in removing pollutant such as chemical oxygen demand (COD), color, and improvement of biodegradability by using this process were also discussed in this chapter. Comparison in term of treatment cost and benefits of the application of chemical as catalyst are briefly elaborated at the end of this chapter.


2015 ◽  
Vol 26 (3) ◽  
pp. 49-53 ◽  
Author(s):  
Anna Kwarciak-Kozłowska ◽  
Aleksandra Krzywicka

Abstract The goal of this article was to compare the efficiency of Fenton and photo-Fenton reaction used for stabilised landfill leachate treatment. The mass ratio of COD:H2O2 was fixed to 1:2 for every stages. The dose of reagents (ferrous sulphate/hydrogen peroxide) was different and ranged from 0.1 to 0.5. To determine the efficiency of treatment, the BOD (biochemical oxygen demand COD (chemical oxygen demand), TOC (total organic carbon) , ammonia nitrogen and BOD/COD ratio was measured. The experiment was carried out under the following conditions: temperature was 25ºC, the initial pH was adjusted to 3.0. Every processes were lasting 60 minutes. The most appropriate dose of reagents was 0.25 (Fe2+/H2O2). It was found that the application of UV contributed to increase of COD, TOC and ammonia removal efficiencies by an average of 14%.


2018 ◽  
Vol 25 (13) ◽  
pp. 12538-12544 ◽  
Author(s):  
Osman Serdar ◽  
Nuran Cikcikoglu Yildirim ◽  
Sule Tatar ◽  
Numan Yildirim ◽  
Aysenur Ogedey

2010 ◽  
Vol 61 (5) ◽  
pp. 1257-1266 ◽  
Author(s):  
Soraya Mohajeri ◽  
Hamidi Abdul Aziz ◽  
Mohamed Hasnain Isa ◽  
Mohammad Ali Zahed ◽  
Mohammed J. K. Bashir ◽  
...  

In the present study, Electrochemical Oxidation was used to remove COD and color from semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. Experiments were conducted in a batch laboratory-scale system in the presence of NaCl as electrolyte and aluminum electrodes. Central composite design (CCD) under Response surface methodology (RSM) was applied to optimize the electrochemical oxidation process conditions using chemical oxygen demand (COD) and color removals as responses, and the electrolyte concentrations, current density and reaction time as control factors. Analysis of variance (ANOVA) showed good coefficient of determination (R2) values of >0.98, thus ensuring satisfactory fitting of the second-order regression model with the experimental data. In un-optimized condition, maximum removals for COD (48.77%) and color (58.21%) were achieved at current density 80 mA/cm2, electrolyte concentration 3,000 mg/L and reaction time 240 min. While after optimization at current density 75 mA/cm2, electrolyte concentration 2,000 mg/L and reaction time 218 min a maximum of 49.33 and 59.24% removals were observed for COD and color respectively.


Electrocoagulation (EC) process uses direct electric current source between metal electrode submerged in the effluent that results in electrode dissolution, with a suitable pH, metal ion can form a wide range of metal hydroxide and coagulated species that destabilized and dissolved contaminants absorbed. Electrocoagulation (EC) has been working for the percentage removal of BOD (Biochemical oxygen demand)/ chemical oxygen demand (COD) ratio, Color and COD on leachate in a batch Electrocoagulation reactor using stainless steel (SS) electrode. EC technology depends on so many factors such as electrode material, initial pH, applied voltage, inter-electrode distance, and electrolysis time. From the experimental work, results reveal that the maximum percentage of removal achieved were COD and Color 73.5% and 65.0% respectively and increasing BOD/COD ratio 0.11 to 0.62. The optimum inter-electrode distance 1cm with electrode surface area 35 cm2 and optimum electrolysis time of 120 min at optimum applied voltage 12V, stirring speed 250 rpm and pH 9.8. These results proved that the EC process is an appropriate and proficient approach for treating the landfill leachate.


Sign in / Sign up

Export Citation Format

Share Document