scholarly journals Removal of COD from Oil Recovery Industry Wastewater by the Advanced Oxidation Processes(AOP) Based on H2O2

2013 ◽  
Vol 10 (1) ◽  
pp. 31-38 ◽  

The combinations of H2O2/Fe+2, UV/H2O2/Fe+2 and UV/H2O2 process were investigated on treatment of oil recovery industry wastewater. Treatment of oil recovery industry wastewater, a typical high pollution strength industrial wastewater (chemical oxygen deman (COD): 21000 mg l-1, biological oxygen demand (BOD): 8000 mg l-1, oil and grease:1140 mg l-1, total dissolved solids (TDS): 37000 mg l-1, total suspended solids: 2580 mg l-1), was carried out by batch oxidation processes. The optimal mass ratio for H2O2/Fe+2 yielding the highest COD removal was found to be 8.658 corresponding to 200.52 g 1-1 H2O2 and 23.16 g l-1 Fe+2 concentrations for 60 minutes reaction time. Fenton process gave a maximum COD reduction of 86% (from 21000 to 2980 mg l-1) and the combination of UV/H2O2 gave a COD reduction of 39% (from 21000 to 12730). The percentage of removal, after the total reaction time (3.5h), H2O2: 8.4 g l-1 and Fe+2: 0.05g l-1, in the photo Fenton process, corresponded to 81 % of the total initial COD (4200 mg l-1). The oxidative ability of the UV/Fe+2/H2O2 process (81%) was greater than that of the UV/H2O2 process (55%) for 80% diluted wastewater. COD removal efficiency for UV/H2O2 process (COD/H2O2=1/2 (w/w)) was 90%, 55%, and 39 when initial COD was 1050, 4200, and 21000 mg l-1, respectively, whereas COD removal was 943, 2320, and 8270 mg l-1, respectively.

2013 ◽  
Vol 69 (2) ◽  
pp. 343-349 ◽  
Author(s):  
Reza Davarnejad ◽  
Mostafa Keshavarz Moraveji ◽  
Masoud Pirhadi ◽  
Mohsen Mohammadi

The operating parameters in the electro-Fenton process were simulated using computational fluid dynamics (CFD). The effects of H2O2/Fe2+ molar ratio, current density, pH and reaction time were numerically investigated. The results were compared with the experimental data. The simulated data showed that maximum chemical oxygen demand (COD) removal was around 91.52% at pH of 3.27, H2O2/Fe2+ molar ratio of 1.16, current density of 59.29 mA/cm2 and reaction time of 41.7 min while the experimental data obtained from the literature showed a maximum COD removal (94.7%) at pH of 3, H2O2/Fe2+ molar ratio of 1, current density of 49 mA/cm2 and reaction time of 43 min.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Edris Bazrafshan ◽  
Hossein Moein ◽  
Ferdos Kord Mostafapour ◽  
Shima Nakhaie

Dairy industry wastewater is characterized by high biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and other pollution load. The purpose of this study was to investigate the effects of the operating parameters such as applied voltage, number of electrodes, and reaction time on a real dairy wastewater in the electrocoagulation process. For this purpose, aluminum electrodes were used in the presence of potassium chloride as electrolytes. It has been shown that the removal efficiency of COD, BOD5, and TSS increased with increasing the applied voltage and the reaction time. The results indicate that electrocoagulation is efficient and able to achieve 98.84% COD removal, 97.95% BOD5removal, 97.75% TSS removal, and >99.9% bacterial indicators at 60 V during 60 min. The experiments demonstrated the effectiveness of electrocoagulation techniques for the treatment of dairy wastewaters. Finally, the results demonstrated the technical feasibility of electrocoagulation process using aluminum electrodes as a reliable technique for removal of pollutants from dairy wastewaters.


Author(s):  
Vijay A. Juwar ◽  
Ajit P. Rathod

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).


2015 ◽  
Vol 50 (4) ◽  
pp. 349-358
Author(s):  
Lekshmi Ashok ◽  
S. Adishkumar ◽  
J. Rajesh Banu ◽  
Ick Tae Yeom

This study evaluated a ferrioxalate-induced solar photo-Fenton process for natural rubber latex wastewater treatment. The reaction was carried out in a laboratory-scale solar photo-Fenton plug flow baffle reactor. An optimization study was performed using a central composite experimental design including the following variables: pH, initial concentrations of H2O2, Fe2+, and oxalic acid. The photocatalytic degradation efficiency was determined by the analysis of chemical oxygen demand (COD) removal. Under the optimum conditions of pH = 4, Fe2+ = 1.3 g/L, oxalic acid = 2.25 g/L, H2O2 = 82.5 g/L, and solar irradiation time of 6 hours, the COD removal efficiency was 99%. Treatment of latex wastewater by ferrioxalate-induced solar photo-Fenton process increased biodegradability ratio from 0.36 to 0.7 in 2 hours. The overall cost of ferrioxalate-induced solar photo-Fenton oxidation for the treatment of 5 m3 of latex wastewater per day was estimated to be US$85/m3.


2016 ◽  
Vol 11 (1) ◽  
pp. 86-92 ◽  
Author(s):  
M. Basitere ◽  
Y. Williams ◽  
M. S. Sheldon ◽  
S. K. O. Ntwampe ◽  
D. De Jager ◽  
...  

Generally, slaughterhouses have the largest consumption of fresh water and thus generate large quantities of high strength wastewater, which can be treated successfully using low cost biological treatment processes. In this study, the feasibility of using an expanded granular sludge bed (EGSB) anaerobic reactor coupled with anoxic and aerobic bioreactors for the treatment of poultry slaughterhouse wastewater was investigated. The poultry slaughterhouse was characterized by high chemical oxygen demand (COD), 2 to 6 g/L, with average biological oxygen demand of 2.4 g/L and average fats, oil and grease (FOG) being 0.55 g/L. A continuous EGSB anaerobic reactor was operated for 26 days at different hydraulic retention times (HRT), i.e. 7, 4, 3 days, and organic loading rates (OLR) of 0.5, 0.7 and 1.0 g COD/L.day, respectively, to assess the bioremediation of the poultry slaughterhouse wastewater. The average COD removal from the EGSB was 40%, 57% and 55% at the different OLR and HRT assessed. At high OLR of 1.0 g COD/L.day, the overall COD removal from the system (EGSB-anoxic/aerobic) averaged 65%. The system experienced periodical sludge washout during high FOG and suspended solids loading. It was concluded that the EGSB system requires a dissolved air flotation system, for FOG/suspended solid reduction, as the performance of the overall system was observed to deteriorate over time due to the presence of a high quantity of FOG including suspended solids.


2020 ◽  
Vol 81 (2) ◽  
pp. 345-357 ◽  
Author(s):  
Gamze Varank ◽  
Senem Yazici Guvenc ◽  
Ahmet Demir ◽  
Nihal Kavan ◽  
Nurten Donmez ◽  
...  

Abstract In this study, the treatment of paper industry wastewaters by the electrocoagulation (EC) process with a strong oxidant, persulfate addition, was investigated. Persulfate was activated by dissolution of Fe and Al from electrodes during the process. Central composite design method, being one of the response surface methods, was applied for the optimization of process parameters and the development of a mathematical model for chemical oxygen demand (COD) removal from paper industry wastewaters. The effects of S2O8−2/COD ratio, current, pH, and reaction time, being the variables of process, were assessed on the efficiency of contaminant removal. For COD removal in EC processes in which Fe and Al electrodes were used, the model's correlation coefficients (R2) were determined as 90.14% and 87.46%, respectively. As the result of experimental study actualized under optimum conditions determined by the model in order to obtain maximum contaminant removal, COD removal efficiencies were determined as 63.5% and 72.8% respectively for the Fe electrode (S2O8−2/COD ratio: 1.25, current: 4.14 A, pH: 6, and reaction time: 5 minutes), and the Al electrode (S2O8−2/COD ratio: 0.5, current: 4.25 A, pH: 7.25, and reaction time: 25 minutes). Electro-activated persulfate process is an appropriate treatment alternative for COD removal from paper industry wastewaters.


2018 ◽  
Vol 78 (12) ◽  
pp. 2542-2552 ◽  
Author(s):  
Seval Yılmaz ◽  
Emine Esra Gerek ◽  
Yusuf Yavuz ◽  
Ali Savaş Koparal

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.


Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4436 ◽  
Author(s):  
Zhiyong Yang ◽  
Penglei Wang ◽  
Yagang Zhang ◽  
Xingjie Zan ◽  
Wenjuan Zhu ◽  
...  

Polymerization mother liquid (PML) is one of the main sources of wastewater in the chlor-alkali industry. The effective degradation of the PML produced in PVC polymerization using three or five ozone reactors in tandem was designed with a focus on improving the ozonation efficiency. The ozonation efficiency of the tandem reactors for the degradation of PML, along with the effect of ozone concentration, the number of reactors utilized in series, and the reaction time on the chemical oxygen demand (COD) removal were investigated in detail. The results showed that the COD removal increased as the ozone concentration was increased from 10.6 to 60 mg·L−1, achieving 66.4% COD removal at ozone concentration of 80.6 mg·L−1. However, when the ozone concentration was increased from 60 mg·L−1 to 80 mg·L−1, the COD removal only increased very little. The COD decreased with increasing ozone concentration. During the initial degradation period, the degradation rate was the highest at both low and high ozone concentrations. The degradation rate decreased with reaction time. The rate at a low ozone concentration decreased more significantly than at high ozone concentration. Although high ozone concentration is desirable for COD removal and degradation rate, the utilization efficiency of ozone decreased with increasing ozone concentration. The ozone utilization efficiency of the five-reactor device was three times higher than that of three tandem reactors, demonstrating that ozonation utilization efficiency can be improved by increasing the number of tandem reactors. Ozonation in tandem reactors is a promising approach for PML treatment.


2011 ◽  
Vol 64 (12) ◽  
pp. 2433-2438 ◽  
Author(s):  
B. Manu ◽  
S. Mahamood

For the treatment of paracetamol in water, the UV-C Fenton oxidation process and classic Fenton oxidation have been found to be the most effective. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by the Fenton process. Influent pH 3, initial H2O2 dosage 60 mg/L, [H2O2]/[Fe2+] ratio 60 : 1 are the optimum conditions observed for 20 mg/L initial paracetamol concentration. At the optimum conditions, for 20 mg/L of initial paracetamol concentration, 82% paracetamol reduction and 68% COD removal by Fenton oxidation, and 91% paracetamol reduction and 82% COD removal by UV-C Fenton process are observed in a 120 min reaction time. By HPLC analysis, 100% removal of paracetamol is observed at the above optimum conditions for the Fenton process in 240 min and for the UV-C photo-Fenton process in 120 min. The methods are effective and they may be used in the paracetamol industry.


Author(s):  
Reza Davarnejad ◽  
Seyed Amir Mohajerani

Abstract The edible plant oil production factories consume high amounts of water and contaminate the water resources. This type of wastewater consists of high chemical oxygen demand (COD) which should properly be treated by an efficient technique. Furthermore, it is containing some chemicals obtained from several sources such as H3PO4 (from hydration section), NaOH (from neutralization section) and citric acid (from nickel removal section). The conventional techniques cannot efficiently treat it which is full of COD. Therefore, the electro-Fenton process as a rapid, compact and efficient one has been encouraged to be applied. For this purpose, 47 experiments were designed and carried out using iron electrodes to evaluate the effects of five significant independent variables such as reaction time (min), pH, current density (mA/cm2), volume ratio of H2O2/wastewater (ml/l) and H2O2/Fe2+ molar ratio on the COD removal. Response surface methodology (RSM) was employed to assess individual and interactive effects of the parameters. The optimum conditions were experimentally obtained at reaction time of 87.33 min, pH of 3.03, current density of 57 mA/cm2, H2O2/wastewater volume ratio of 2.13 ml/l and H2O2/Fe2+ molar ratio of 3.61 for COD removal of 62.94 %.


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