Effective removal of cefazolin from hospital wastewater by the electrocoagulation process

2019 ◽  
Vol 80 (12) ◽  
pp. 2422-2429 ◽  
Author(s):  
Yahya Esfandyari ◽  
Keivan Saeb ◽  
Ahmad Tavana ◽  
Aptin Rahnavard ◽  
Farid Gholamreza Fahimi

Abstract The present study evaluated the treatment of hospital wastewater by the electrocoagulation process using aluminum and iron electrodes. The effects of pH, voltage and reaction time on the removal efficiencies of the antibiotic cefazolin, chemical oxygen demand (COD) and turbidity were investigated. The results showed that by increasing reaction time and input voltage, the removal efficiency of pollutants was increased. The highest removal efficiency of cefazolin, COD, and turbidity occurred at neutral pH, which may have been related to the formation of aluminum hydroxide (Al(OH)3) flocs through the combination of aluminum released from the surface of the electrode and the hydroxide ions present in the solution. The conductivity of the treated wastewater at neutral to alkaline pH decreased compared to acidic pH, which may have been due to the adsorption of anions and cations from the solution by the Al(OH)3 flocs. The electrode and energy consumption in the present study was higher than in other studies, which may have been due to the high concentration of COD in and the turbidity of the solution.

2012 ◽  
Vol 14 (3) ◽  
pp. 66-70 ◽  
Author(s):  
Lech Smoczyński ◽  
Kamilla Teresa Muńska ◽  
Bogusław Pierożyński ◽  
Marta Kosobucka

Electrocoagulation makes an alternative method to chemical coagulation. This paper presents the results obtained during the electrocoagulation of the model wastewater using aluminum electrodes. The wastewater was treated by means of chronopotentiometric electrocoagulation process in a static system, at the constant current I = 0.3 A; therefore higher doses of electrocoagulant required longer electrocoagulation time. Changes in zeta potential, pH, turbidity, chemical oxygen demand (COD), suspended solids and total phosphorus concentrations in the treated wastewater were determined. A new method for determining the optimal dosage of the aluminum electrocoagulant was proposed through application of the third degree polynomial function rather than the parabolic equation. An increase in the electrocoagulant dose raised the share of sweep fl occulation in the studied treatment process, resulting in the effective removal over 90% of phosphorus compounds from the system.


2021 ◽  
Vol 8 (3) ◽  
pp. 237-244
Author(s):  
Abdoliman Amouei ◽  
Mehdi Pouramir ◽  
Hosseinali Asgharnia ◽  
Mahmoud Mehdinia ◽  
Mohammad Shirmardi ◽  
...  

Background: Leachate contains toxic and non-biodegradable substances that are not easily treated by conventional treatment methods. This study investigated the effect of pH, current density, and reaction time parameters on the removal of cyanide (CN- ), nitrate (NO3- ), turbidity, and chemical oxygen demand (COD) from leachate by electrocoagulation process. Methods: This study was an experimental one with direct current using four parallel bipolar aluminum electrodes with 90% purity. The length, width, and thickness of the electrodes were 5 cm, 10 cm, and 2 mm, respectively. There were 6 holes with a diameter of 0.7 cm on each of the electrodes. The samples were prepared from the old leachate of solid waste landfill in Ghaemshahr, Iran. Results: In this study, at a current density of 33 mA/cm2 and a time of 60 minutes, the optimum removal efficiency of cyanide (100 %) was obtained at pH 5.5 and pH 10. Moreover, the maximum removal of nitrate (99.65 %) and turbidity (86.41 %) were at pH 5.5 and pH 8.3, respectively and the highest removal efficiency of COD (83.14 %) was obtained at pH 10. Conclusion: The results showed that the removal of cyanide, nitrate, turbidity, and COD increases with increasing current density and reaction time. Due to the proper removal of nitrate and cyanide from leachate by electrocoagulation, nitrate and cyanide amounts were less than the allowable contamination level. Based on the results, electrocoagulation is considered an efficient and effective method for removing nitrate and cyanide from old leachate of municipal solid wastes.


2011 ◽  
Vol 6 (1) ◽  
Author(s):  
M. Behbahani ◽  
M.R. Alavi Moghaddam ◽  
M. Arami

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.


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.


2017 ◽  
Vol 76 (4) ◽  
pp. 776-784 ◽  
Author(s):  
Mijia Zhu ◽  
Jun Yao ◽  
Zhonghai Qin ◽  
Luning Lian ◽  
Chi Zhang

Wastewater produced from polymer flooding in oil production features high viscosity and chemical oxygen demand because of the residue of high-concentration polymer hydrolysed polyacrylamide (HPAM). In this study, steel slag, a waste from steel manufacturing, was studied as a low-cost adsorbent for HPAM in wastewater. Optimisation of HPAM adsorption by steel slag was performed with a central composite design under response surface methodology (RSM). Results showed that the maximum removal efficiency of 89.31% was obtained at an adsorbent dosage of 105.2 g/L, contact time of 95.4 min and pH of 5.6. These data were strongly correlated with the experimental values of the RSM model. Single and interactive effect analysis showed that HPAM removal efficiency increased with increasing adsorbent dosage and contact time. Efficiency increased when pH was increased from 2.6 to 5.6 and subsequently decreased from 5.6 to 9.3. It was observed that removal efficiency significantly increased (from 0% to 86.1%) at the initial stage (from 0 min to 60 min) and increased gradually after 60 min with an adsorbent dosage of 105.2 g/L, pH of 5.6. The adsorption kinetics was well correlated with the pseudo-second-order equation. Removal of HPAM from the studied water samples indicated that steel slag can be utilised for the pre-treatment of polymer-flooding wastewater.


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).


2018 ◽  
Vol 78 (6) ◽  
pp. 1260-1267 ◽  
Author(s):  
Mohammad Malakootian ◽  
Mohammad Reza Heidari

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.


2020 ◽  
Vol 82 (9) ◽  
pp. 1795-1807 ◽  
Author(s):  
Dejun Bian ◽  
Zebing Nie ◽  
Fan Wang ◽  
Shengshu Ai ◽  
Suiyi Zhu ◽  
...  

Abstract A micro-pressure swirl reactor (MPSR) was developed for carbon and nitrogen removal of wastewater, in which dissolved oxygen (DO) gradient and internal circulation could be created by setting the aerators along one side of the reactor, and micro-pressure could be realized by sealing most of the top cap and increasing the outlet water level. In this study, velocity and DO distribution in the reactor was measured, removal performance treating high-concentration wastewater was investigated, and the main functional microorganisms were analyzed. The experiment results indicated that there was stable swirl flow and spatial DO gradient in MPSR. Operated in sequencing batch reactor mode, distinct biological environments spatially and temporally were created. Under the average influent condition of chemical oxygen demand (COD) concentration of 2,884 mg/L and total nitrogen (TN) of 184 mg/L, COD removal efficiency and removal loading was 98% and 1.8 kgCOD/(m3·d) respectively, and TN removal efficiency and removal loading reached up to 90% and 0.11 kgTN/(m3·d) respectively. With efficient utilization of DO and simpler configuration for simultaneous nitrification and denitrification, the MPSR has the potential of treating high-concentration wastewater at lower cost.


2011 ◽  
Vol 1 (3) ◽  
pp. 179-184 ◽  
Author(s):  
Beenish Saba ◽  
Tariq Mahmood ◽  
Bushra Zaman ◽  
Imran Hashmi

Reclaimed wastewater reuse for irrigation to crop plants is evaluated in a laboratory-scale experiment to assess growth and water saving potential from natural resources. A prototype laboratory-scale treatment plant was established for this purpose with suspended and attached growth configurations. Chakwal wheat variety was selected to examine growth parameters. The removal of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were evaluated to check the quality of treated water. It was found that a suspended growth sequencing batch bioreactor (SGSBBR) achieved 97% ± 2 removal efficiency over a 4 h hydraulic retention time (HRT). For an attached growth sequencing batch bioreactor (AGSBBR) results showed 98% ± 2 removal efficiencies with polyurethane. TN and TP removal efficiency was 58.7 ± 3% and 64 ± 4.8% in SGSBBR, 53 ± 0.17% and 67 ± 2.7% in polyurethane. AGSBBR enhanced performance with AGSBBR may be due to enforced anoxic/aerobic conditions in the inner layers of biofilm formed on biocarriers which facilitate the required metabolic conditions for treating high strength wastewater. Plant growth was visibly greater in SGSBBR treated wastewater than AGSBBR because of less nutrient removal.


2020 ◽  
Vol 20 (3) ◽  
pp. 536
Author(s):  
Nurulhuda Amri ◽  
Ahmad Zuhairi Abdullah ◽  
Suzylawati Ismail

This work compares commercial aluminium electrode for use in the treatment of wastewater by electrocoagulation process against waste aluminium cans electrode. The applicability of the waste aluminium cans electrode was tested for decolorization of Acid Red 18 dye as a model pollutant. The batch electrocoagulation process using both types of electrode was conducted at a current density of 25 mA/cm2, a pH of 3, an initial concentration of 100 mg/L and 25 min of reaction time. The elemental composition and surface morphology of both electrode materials and the sludge produced were analyzed using SEM-EDX to establish the correlation between the properties and characteristics of both electrode materials with their dye removal performance. The results demonstrated that waste aluminium cans performed better than commercial aluminium electrode with a removal efficiency of 100% in 25 min of reaction time. This was due to the higher Al dissolution of waste aluminium cans electrode that contributed to the larger amount of Al3+ released into the solution to consequently form more flocs to remove the dye molecules. In conclusion, the proposed waste aluminium electrode was considered as efficient and cost-effective and had the potential to replace the conventional ones in treating colored industrial wastewater using electrocoagulation process.


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