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Showing 5 results for Aluminum
Treatment of Synthetic Wastewater Containing Reactive Red 198 by Electrocoagulation Process
A Dalvand, A Jonidi Jafari, M Gholami, A Ameri, N.m Mahmoodi,
Volume 4, Issue 1 (5-2011)
Abstract

Background and Objectives: Discharge of textile colored wastewater industries without providing enough treatment in water bodies, is harmful for human and aquatic organisms and poses serious damages to the environment. Most of conventional wastewater treatment methods don't have enough efficiency to remove textile dyes from colored wastewater thus in this research the efficiency of electrocoagulation treatment process with aluminum electrodes for treatment of a synthetic wastewater containing C.I. Reactive Red 198 in batch reactor was studied.
Material and Methods: The experiment conducted in a Plexiglas reactor with a working volume of 2L that equipped with 4 aluminum electrodes. The effects of operating parameters such as voltage, time of reaction, initial dye concentration and interelectrode distance on the color removal efficiency, electrical energy consumption and electrode consumption were investigated.
Results: in the optimum operational condition electrocoagulation, is able to remove color and COD as high as 99.1 and 84.3% in aluminum electrode in 75 minutes at 20 volt and 2 cm interelectrode distance, respectively. Under this condition, operating cost was 2986 rails per cubic meter of treated wastewater. Increase in the interelectrode distance and initial dye concentration,lead to the decrease in efficiency of dye and COD removal.While as the voltage and time of reaction increased, energy consumption, electrode consumption, final pH and color removal, increased too.
Conclusion: electrocoagulation process by aluminum electrode is an efficient and suitable method for reactive dye removal from colored wastewater.


Survey of PAC Performance for Removal of Turbidity, COD, Coliform Bacteria, Heterotrophic Bacteria from Water of Karoon River
A Mirzaei, A Takdastan, N Alavi Bakhtiarvand,
Volume 4, Issue 3 (10-2011)
Abstract

Backgrounds and Objectives: Selection of  proper coagulants for turbidity removal and determination of effective methods to reduce coagulants dose and related costs in water treatment plants is of critical importance. The present study investigates the effect of returned sludge on improving the performance of poly-aluminum chloride (PAC) in turbidity, coliform bacteria, heterotrophic bacteria removal from drinking water during rapid mixing phase.
Materials and Methods: In order to determine the optimal returned sludge volume injected during rapid mixing with PAC for turbidity, total coliform and hetrophic bacteria, experiments were conducted based on variables such as injected silt volume (from 0 - 125 ml), and varying turbidities from 58 - 112 NTU. At the end of each JAR experiments, remaining turbidity , microbial parameters of samples were measured . Coagulant efficiency in turbidity removal and microbial parameters were determined by Covariance, Duncan analyses and graphs were drawn by MS Excel . The results statistically showed significant among variables (P<0.05).
Results: The results showed that the maximum turbidity removal efficiency of 98.92 at 30 ppm was 10 ml while the maximum turbidity removal efficiency of 98.31 at 10 ppm was 4 ml. The maximum total coliform removal efficiency  of 95.68 obtained for 10 ppm in 10 cc injected sludge volume.
Conclusion: This study shows that addition of returned sludge to flash mixing can reduce the turbidity of samples.


Performance Evaluation of Electrochemical Process using Iron and Aluminum Electrodes in Phenol  Removal from Synthetic Aqueous Environment 
Hamed Biglari, Edris Bazrafshan,
Volume 5, Issue 4 (2-2013)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Phenol is one of the most important organic chemicals presenting in water and other environments. It not only brings about hygienic problems but also results in forming 11 toxic priority pollutants in aqueous environments. Hence, the performance of electrocoagulation process using iron and aluminum sacrificial anodes was investigated for removal of phenol.
Materials and Methods: We used a glass tank in 1.56 L volume (effective volume 1 L) equipped with four iron and aluminum plate electrodes to do experiments (bipolar mode). The tank was filled with synthetic wastewater containing phenol in concentration of 5, 20, 40, and 70 mg/l and to follow the progress of the treatment, each sample was taken at 20 min intervals for up to 80 min. The percent of phenol removal was measured at pH 3, 5, 7, and 9 electrical potential range of 20, 40, and 60 volts and electrical conductivity of 1000, 1500, 2000, and 3000 µs/cm.
Results: It was found that the most effective removal capacities of phenol (95 and 98 %) could be achieved when the pH was kept 7 and 5 for iron and aluminum electrodes, reaction time  80 min, electrical conductivity 3000 µs/cm, initial concentration of phenol 5 mg/l, and electrical potential in the range of 20-60 V.
Conclusion: The method was found to be highly efficient and relatively fast compared with existing conventional techniques and also it can be concluded that the electrochemical process has the potential to be utilized for the cost-effective removal of phenol from water and wastewater.


Aluminum migration from semi-rigid packaging into foods during storage
F Ahmadi, N Rastkari, P Sadighara, Gh Jahed Khaniki,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: Aluminum (Al) is a neurotoxic agent and this element is being associated with Alzheimer disease. The use of semi-rigid packaging has been increased in recent years. In these packages, the main layer is aluminum. The purpose of this study was to determine the Al concentration in foods packaged in semi-rigid packaging in during storage time.
Materials and Methods: Al concentration of the samples (Joje kabab, khorake morgh, khoresh gheymeh, n=36) was determined at different storage times (0, 60, 120, and 180 days after packaging). Aluminum was determined by ICP-OES after wet digestion method of the samples. A two-way analysis of variance was used to analyze the results with respect to time and food factors.
Results: The effect of storage time on Al concentration was significant p˂0.001. The samples that were stored longer had significantly higher aluminum concentrations. The highest concentration was determined in Joje kabab (3.27 ±0.93 ppm( and lowest Al content was determined in khoresh gheymeh (1.04 ± 0.16 ppm). The results showed that Al concentration of the foods packaged in semi-rigid packaging increased significantly during storage.
Conclusion: Considering the present state of knowledge and the suggested provisional tolerable daily intake of 1 mg/kg body weight per day of according to World Health Organization, Al leaching from semi-rigid packages may add low doses of Al into the diet.
 

Effectiveness of chemical and electrical coagulation process in removing fluoride from the wastewater of the pre-painting unit of the automotive industry
Sakine Shekoohiyan, Mojtaba Pourakbar, Asghar Zohdi Shiran, Farshid Ghanbari, Mostafa Mahdavianpour, Ehsan Aghayani,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: The development of the automobile industry has caused various pollutants to enter the environment, one of which is fluoride. Therefore, this study aims to improve the fluoride removal from wastewater pre-paint units of the automotive industry to achieve discharge standards to surface waters.
Materials and Methods: The study is descriptive and on an applied scale, which has been carried out to compare the efficiency of the chemical coagulation process using lime and alum, as well as the electrocoagulation process using aluminum anodes in the presence of lime to remove fluoride.
Results: The results of real wastewater characteristics showed that the pH of wastewater is in the range of 6.1 to 6.3, and its fluoride concentration is in the range of 45 to 55 mg/L. The results of the experiments show that in the most optimal possible state in the chemical coagulation process, it is possible to achieve fluoride removal efficiency in the range of 76 to 81 percent. However, the removal efficiency in the electrocoagulation process using an aluminum anode at a concentration of 5 mol/L of calcium ions, and current density of 20 A/m2 after reaction time of min 20 to 99% can also be achieved.
Conclusion: Considering the high fluoride removal rate (more than 99%) in the electrocoagulation process in the presence of calcium ions, this process can be introduced as an efficient technology for fluoride removal.
 

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