List of Articles بازده حذف

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  1 - Evaluation of Effective Parameters in Organic Matters Removal Efficiency of Anaerobic Baffled Reactor Employing Electrolysis Process
  Gagik Badalians Gholikandi Behnam Inanloo Beklar Maryam Amouamouha
  10.22034/jest.2020.31536.3982
  Background and Objective: Following the results of the electrolysis process application to upgrade the anaerobic baffled reactor for treating wastewater, the present study was conducted to evaluate the EABR performance efficiency, considering hydraulic retention time (H More

  Background and Objective: Following the results of the electrolysis process application to upgrade the anaerobic baffled reactor for treating wastewater, the present study was conducted to evaluate the EABR performance efficiency, considering hydraulic retention time (HRT), current density and organic loading.   Methods: In this study, a semi-industrial pilot of ABR with total volume of 72 L was studied before and after integration with an electrolysis system. The performance of the reactor was evaluated in terms of COD removal and bacterial adaption time. Findings: The findings revealed that a HRT reduction from 45 to 38 and 29 hours results in a decrease of COD removal efficiency from 77.6 to 74.9 and 72.2 % respectively. Also, a current density reduction from 3 to 2, 1, and 0.5 Mill ampere/cm2 results in a decreasing COD removal efficiency from 77.6 to 73.5, 71.2, and 70 % respectively. Moreover, an increasing organic loading from 700 to 2400 mg/L enhanced the COD removal efficiency from 77.6 to 90.2 %. Result and Discussion: The results showed that by increasing organic loading from 700 to 1000, 1500, 2000, and 2400 mg/L the necessary HRT for achieving operation stability increases from 3 to 8 days, which is less than in conventional ABR. Therefore, employing electrolysis process is a sustainable method for improving ABR performance efficiency.  Manuscript profile
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  2 - Ex-situ removal of crude oil from a contaminated soil using Sodium Dodecyl Sulfate (SDS)
  Mehdi Hosnani Hossein Amani Mohammad Reza Sarmasti Emami
  10.22034/jest.2019.14541
  Background Objective: Soil is the basic component of environment and the main source of food production and its contamination can cause pose many challenges for humans and other living organisms. Although many studies have been done separately to eliminate organic pollu More

  Background Objective: Soil is the basic component of environment and the main source of food production and its contamination can cause pose many challenges for humans and other living organisms. Although many studies have been done separately to eliminate organic pollutants such as benzene and phenolic compounds from soil, a few studies yet have been done on the removal of crude oil which contains different types of hydrocarbon compounds from the soil. The aim of this study is to determine the removal of crude oil from the soil and provide a comprehensive model. Method: In this study, the ex-situ soil washing method with surface active agent has been used to remove crude oil from soil. For this purpose, first, the soil was artificially polluted with crude oil and then the effects of various parameters such as surfactant concentration in aqueous solutions, the initial concentration of contaminant in the soil, pH, volume of detergent solution, stirring rate, duration of the process and system temperature were evaluated. Findings: The results showed the optimal conditions for the removal of crude oil were concentration of surfactant in aqueous solution of 0.5% (w/w), initial concentration of crude oil of 5% (w/w), detergent solution pH=11, detergent solution volume of 50 ml, stirring rate of 200 rpm, experiment duration of 15 m and temperature of 45 °C. In optimal condition, about 96% of crude oil was removed from the soil. Discussion and Conclusion: According to the obtained results, surfactants can be used as a proper substance to remove oil contaminants from soil with a good efficiency. Manuscript profile
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  3 - Feasibility of remediation of diesel contaminated soils using surfactants by use of experimental pilot
  Ehsan Salehian Ahmad Khodadadi Hossein Gangidoust
  Nowadays soil contamination by oil production due to leakage of fuel storage and transition hazards is an important environmental problem. Due to the additional hazard of transition to the human food chain, there is the possibility for pollution of ground water. Therefo More

  Nowadays soil contamination by oil production due to leakage of fuel storage and transition hazards is an important environmental problem. Due to the additional hazard of transition to the human food chain, there is the possibility for pollution of ground water. Therefore in situ remediation of oil contaminated soil is very important. In this investigation the effective parameters on diesel soil remediation by soil washing using SDS surfactant were investigated. For modeling of contaminated land remediation the contaminated soil columns was used. Soil columns were contaminated with diesel in amount of 10000 ppm and 20000 ppm. In this study the effect of pH, surfactant concentration in washing solution and initial contamination amount were investigated. Results showed that in all states the quantity of remediation for acidic states is very low and efficiency of remediation when using only water is (1:3) of maximum amount. For soil with initial contamination amount of 10000 ppm the maximum efficiency is for surfactant in concentration of 0.3 and pH=11 and for soil with initial contamination amount of 20000 ppm the maximum efficiency is for surfactant in concentration of 0.1 and pH=11. By increasing the amount of surfactant concentration the permeability of soil decrease and in pH=11 the amount of permeability is maximum. With increasing initial contamination quantity, the velocity of increasing of remediation and permeability decreased. Consequently in the low level of contamination the effect of washing solution pH in soil remediation is greater in comparison with high levels of contamination. Manuscript profile
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  4 - Synthesis of GO-Cu-BTC graphene oxide at the Green and in situ under solvent-free conditions by the mechanochemical methods and evaluation of kinetic and isotherm properties of cadmium removal
  hamideh hamzeh ali sara mashkouri beheshteh sohrabi nazari mohammad reza naimi jamal leila panahi
  In this research, GO-Cu-BTC nanocomposite was prepared at the green, in situ under solvent-free by using the mechanical method without purification. XRD and FESEM demonstrated the structure of nanocomposite. In order to investigate the application of the nanocomposites More

  In this research, GO-Cu-BTC nanocomposite was prepared at the green, in situ under solvent-free by using the mechanical method without purification. XRD and FESEM demonstrated the structure of nanocomposite. In order to investigate the application of the nanocomposites synthesized in green conditions, cadmium heavy metal removal was studied. Here, kinetic and isotherm studies of metal removal were performed and the concentration of cadmium ions was measured by atomic absorption spectrometry. The results showed that the adsorption capacity of the cadmium by the nanocomposite adsorbent was dependent on parameters such as pH and reaction time. Optimal conditions showed that 6 mg of nanocomposite removed 94% of water-soluble cadmium at pH 8. The results showed that the isotherm data followed the Langmuir model. In this study, it is found that GO-Cu-BTC has a high ability to adsorb cadmium and can be used as a low-cost adsorbent. Manuscript profile