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Jeehyeong Khim - One of the best experts on this subject based on the ideXlab platform.
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Effect of Ultrasound on Surfactant Aided Soil Washing for Diesel Decontamination
2020Co-Authors: Jeehyeong Khim, Qiong Yuan, Anna Hwang, In-chul ParkAbstract:There are many kinds of in-situ and ex-situ remediation technologies for Soil and ground water contamination. Soil Washing is typically used ex-situ remediation method for contaminated Soils by separating the contaminated fraction for disposal. Various researches have been undertaken to increase the effectiveness of the Soil Washing including surfactant aided method. The objective of this study is to investigate the effect of ultrasound on the surfactant aided Soil Washing. It is known that sonication can not only directly degrade the chemical itself but also enhance the transport and transfer processes[1-3]. Sonication was used for the desorption of organic [4] as well as the heavy metals [5] from the sediments. In this study, the effects of ultrasonic power on contaminant removal by Soil Washing were investigated. Test conditions involved ultrasonic power intensity at the Soil slurry phase, particle size, and initial concentration on solid phase.
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comparison of energy consumptions between ultrasonic mechanical and combined Soil Washing processes
Ultrasonics Sonochemistry, 2012Co-Authors: Muthupandian Ashokkumar, Jeehyeong KhimAbstract:Abstract Vigorous physical effects including micro-jet and micro-streaming can be induced in heterogeneous systems by acoustic cavitation. This can be useful for the removal of pollutants from contaminated Soil particles. In this study, the diesel removal efficiencies in ultrasonic, mechanical, and combined Soil Washing processes have been compared considering the electrical energy consumptions for these processes. The combined process showed synergistic effects for both removal efficiency and effective volume also has the advantage of a short operation time compared to the sequential processes. Thus the ultrasonic Soil Washing process with mechanical mixing is considered a promising technology for industrial use.
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comparison of ultrasonic and conventional mechanical Soil Washing processes for diesel contaminated sand
Industrial & Engineering Chemistry Research, 2011Co-Authors: Muthupandian Ashokkumar, Jeehyeong KhimAbstract:The effect of ultrasound on the conventional mechanical Soil-Washing process was investigated. To determine the optimal frequency for maximum efficiency, tests were conducted with aluminum foils under four frequencies including 35, 72, 110, and 170 kHz. It is known that the physical effects generated during acoustic cavitation damage the foil by causing pits and holes. The sonication at 35 kHz resulted in maximum damage to the aluminum foil as compared to that observed at other frequencies. Based on these results, 35 kHz was selected for the ultrasonic Soil-Washing processes in this study. The optimal Washing time was found to be 1 min, because there was no significant increase in the removal efficiency over 1 min for the three processes, mechanical, ultrasonic, and combined ultrasonic−mechanical. It was also found that the combined process enhanced the performance of the Soil-Washing process significantly as compared to other two processes in terms of (i) diesel removal efficiency, (ii) process time, (ii...
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effect of ultrasound on surfactant aided Soil Washing
Japanese Journal of Applied Physics, 2007Co-Authors: Seungmin Na, Anna Hwang, Yongwoon Park, Jeong Sook Ha, Jeehyeong KhimAbstract:The use of ultrasound as an enhancement mechanism in the surfactant-aided Soil-Washing process was examined by conducting desoption tests of Soils contaminated with naphthalene or diesel-oil. The experiments were conducted to elucidate the effect of ultrasound on the mass transfer from Soil to the aqueous phase using naphthalene-contaminated Soil. In addition, the use of ultrasound for the diesel-oil-contaminated Soil was investigated under a range of conditions of surfactant concentration, sonication power, duration, Soil/liquid ratio, particle size and initial diesel-oil concentration. The ultrasound used in the Soil-Washing process significantly enhanced the mass transfer rate from the solid phase to the aqueous phase. The removal efficiency of diesel-oil from the Soil phase generally increased with longer sonication time, higher power intensity, and large particle size.
Manuel A. Rodrigo - One of the best experts on this subject based on the ideXlab platform.
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Electrolysis with diamond anodes of the effluents of a combined Soil Washing - ZVI dechlorination process
Journal of Hazardous Materials, 2019Co-Authors: C. Carvalho De Almeida, M. Muñoz-morales, Cristina Sáez, Pablo Cañizares, Carlos A. Martínez-huitle, Manuel A. RodrigoAbstract:Abstract In this work, a new Soil Washing process in which Soil-Liquid extraction technology is enhanced by adding iron particles (zero valent iron nanoparticles or granules) was investigated to remove clopyralid from spiked Soils. This novel approach can be efficiently used to extract chlorinated hydrocarbons from Soil and aims to obtain Soil-Washing wastes with low content of hazardous chlorinated species. The iron particles used were subsequently removed from the treated Soil using magnetic fields. Then, the complete mineralization of the produced Soil Washing effluents was successfully achieved by applying anodic oxidation with diamond anodes in an electrochemical flow cell. Results demonstrated that, opposite to what it was initially expected, no improvements in the efficiency of the electrochemical process were observed by adding iron particles during the Soil Washing. This behavior is explained in terms of the lower electrochemical reactivity of the dechlorinated derivatives produced. Although results are not as promising as initially expected, it does not mean a completely negative outcome for the use of ZVI during Washing, because the hazardousness of the pollutants is rapidly decreased in the initial stages of the Soil-Washing, opening the possibility for the combination of this technology with other processes, such as biological treatment.
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Improving biodegradability of Soil Washing effluents using anodic oxidation.
Bioresource Technology, 2017Co-Authors: María Belén Carboneras, Pablo Cañizares, Manuel A. Rodrigo, José Villaseñor, Francisco Jesus Fernandez-moralesAbstract:Abstract In this work, a combination of electrochemical and biological technologies is proposed to remove clopyralid from Soil Washing Effluents (SWE). Firstly, Soil Washing was carried out to extract clopyralid from Soil. After that, four different anodes—Ir-MMO, Ru-MMO, pSi-BDD and Carbon Felt (CF)—were evaluated in order to increase the biodegradability of the SWE. CF was selected because was the only one able to transform the pesticide to a more biodegradable compounds without completely mineralizing it. Finally, biological oxidation tests were performed to determine the aerobic biodegradability of the SWE generated. From the obtained results, it was observed that at the beginning of the electrolysis the toxicity slightly increased and the biodegradability decreases. However, for electric current charges over 2.5 A·h dm−3 the toxicity drastically decreased, showing an EC50 of 143 mg L−1, and the BOD5/COD ratio increased from 0.02 to 0.23.
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remediation of Soils polluted with lindane using surfactant aided Soil Washing and electrochemical oxidation
Journal of Hazardous Materials, 2017Co-Authors: M Munozmorales, Cristina Sáez, Pablo Cañizares, M Braojos, Manuel A. RodrigoAbstract:Abstract In this work the complete treatment of Soil spiked with lindane is studied using surfactant-aided Soil-Washing (SASW) to exhaust lindane from Soil and electrolysis with diamond anodes to mineralize lindane from the Soil Washing fluid (SWF) waste. Results demonstrated that this technological approach is efficient and allow to remove this hazardous pollutant from Soil. They also pointed out the significance of the ratio surfactant/Soil in the efficiency of the SASW process and in the performance of the later electrolysis used to mineralize the pollutant. Larger values of this parameter lead to effluents that undergo a very efficient treatment which allows the depletion of lindane for applied charges lower than 15 Ah L −1 and the recovery of more than 70% of the surfactant for the regeneration of the SWF.
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UV assisted electrochemical technologies for the removal of oxyfluorfen from Soil Washing wastes
Chemical Engineering Journal, 2017Co-Authors: E.v. Dos Santos, Pablo Cañizares, Carlos A. Martínez-huitle, C. Sáez, Manuel A. RodrigoAbstract:Abstract In this work, it is studied the treatment of Soil polluted with oxyfluorfen by Surfactant-Aided Soil-Washing (SASW) and after that, photo-electrolysis was used for the treatment of the Soil-Washing fluid produced. This liquid waste is characterized by the high concentration of micelles of pesticide and surfactant (sodium dodecyl sulfate, SDS), whose initial size depends on the ratio Soil-surfactant used in the Soil Washing treatment. The waste treatment is studied in terms of the decrease in size of the particles and the depletion of the pollutants. Results clearly demonstrate that photo-electrolysis with diamond electrodes is a very effective treatment technology with results that overcome those obtained by single photolysis and/or single electrolysis with diamond electrodes. The greater improvements attained by combining UV irradiation to the electrolysis were observed in the removal of the pesticide while the removal of the surfactant was little affected. Electrolysis does not only deplete the complete concentration of pesticide but it also shows to be very efficient in the depletion of the surfactant, preventing its potential recycle. The significant concentration of sulfate released during the attack to the surfactant and the effect of the peroxosulfate anions that are formed from the anodic oxidation of that anion, explain the improved performance of the technology in the treatment of Washing fluids with higher concentrations of SDS.
Jeffrey H Harwell - One of the best experts on this subject based on the ideXlab platform.
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surfactant selection for enhancing ex situ Soil Washing
Water Research, 1999Co-Authors: S Deshpande, Borjier Shiau, D Wade, David A Sabatini, Jeffrey H HarwellAbstract:Ex situ Soil Washing is commonly used for treating contaminated Soils by separating the most contaminated fraction of the Soil for disposal. Surfactant-enhanced Soil Washing is being considered with increasing frequency to actually achieve Soil-contaminant separation. In this research eight anionic and nonionic surfactants were evaluated for the enhanced Soil Washing of three different Soils contaminated with petroleum hydrocarbons. Enhanced Soil Washing occurred at surfactant concentrations below and above the CMC indicating the occurrence of both Soil rollup and solubilization mechanisms. In certain cases the lower CMC of nonionic surfactants made them attractive candidates while in other cases the lower sorption and higher solubilization potential of select anionic surfactants made them the preferred choice. Surfactant-induced foaming and turbidity are operating considerations that can also impact surfactant selection. When selecting a surfactant for a given Soil-contaminants system we thus recommend evaluating both anionic and nonionic surfactants at concentrations below and above their CMC, and we suggest that the methodology we describe in this paper is a good approach for making the final surfactant selection.
Raffaele Marotta - One of the best experts on this subject based on the ideXlab platform.
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Solar photocatalytic processes for treatment of Soil Washing wastewater
Chemical Engineering Journal, 2017Co-Authors: Luca Onotri, Marco Race, Marco Guida, Laura Clarizia, Michela Alfè, Roberto Andreozzi, Raffaele MarottaAbstract:Abstract In the present work the use of a sequence of two solar photocatalytic processes was investigated for the removal of copper, iron, zinc and ethylenediaminedisuccinic acid (EDDS), used as chelating agent, from real Soil Washing effluents. Removal efficiencies of 93.5% (copper), 99.6% (iron), 99.4% (zinc), 97.2% (EDDS) and 80.7% (TOC) were achieved through outdoor solar photocatalytic treatments using parabolic trough collectors and carried out in Naples (Italy, N 40°50′, E 14°12′) in the period June–July 2015. These removal efficiencies were achieved for an incident UVA solar energy per unit volume ( Q j,n ) of 580 kJ·L −1 , calculated by taking into account the irradiated surface area of the photoreactor estimated in the present work (9.79 × 10 −2 m 2 ) and the solar irradiance measurements collected during the experiments. The results suggest that the two-step solar process adopted can be proposed as a useful solution to the problem of heavy metals and chelating organic agents removals from Soil Washing. The ecotoxicological assessment, using different living organisms ( Daphnia magna , Vibrio fischeri , Pseudokirchneriella subcapitata , Lepidium sativum and Caenorhabditis elegans ), showed a noticeable decrease of the ecotoxicity of the Soil Washing effluents after the two-step photocatalytic process.
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Photocatalytic processes assisted by artificial solar light for Soil Washing effluent treatment.
Environmental Science and Pollution Research, 2016Co-Authors: Suéllen Satyro, Marco Race, Raffaele Marotta, Márcia Dezotti, Marco Guida, Laura ClariziaAbstract:Contaminated Soil has become a growing issue in recent years. The most common technique used to remove contaminants (such as metals) from the Soil is the Soil Washing process. However, this process produces a final effluent containing chelating agents (i.e., ethylenediaminedisuccinic acid, also known as EDDS) and extracted metals (i.e., Cu, Fe, and Zn) at concentrations higher than discharge limits allowed by the Italian and Brazilian environmental law. Therefore, it is necessary to develop further treatments before its proper disposal or reuse. In the present study, Soil Washing tests were carried out through two sequential paths. Moreover, different artificial sunlight-driven photocatalytic treatments were used to remove Cu, Zn, Fe, and EDDS from Soil Washing effluents. Metal concentrations after the additional treatment were within the Brazilian and Italian regulatory limits for discharging in public sewers. The combined TiO2-photocatalytic processes applied were enough to decontaminate the effluents, allowing their reuse in Soil Washing treatment. Ecotoxicological assessment using different living organisms was carried out to assess the impact of the proposed two-step photocatalytic process on the effluent ecotoxicity.
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simultaneous removal of heavy metals from field polluted Soils and treatment of Soil Washing effluents through combined adsorption and artificial sunlight driven photocatalytic processes
Chemical Engineering Journal, 2016Co-Authors: Suéllen Satyro, Marco Race, Marco Guida, Francesco Di Natale, Alessandro Erto, Raffaele MarottaAbstract:This paper proposes a process for reducing the content of copper and zinc in polluted Soils and a combined photocatalytic-physical process for the treatment of the Soil Washing effluents. For this purpose, real Soil samples were taken from the “Land of Fires”, a region in Southern Italy which is known for its high incidence of cancer mortality. Ethylenediamine-N,N′-disuccinic acid (EDDS) was used to extract the heavy metals from the contaminated Soil. The Soil Washing effluents were treated through a sequence of photocatalytic and adsorption processes to lower the concentration values of metals (Cu, Zn, Fe and Mn) below the limits of national legislation for discharge in municipal sewers and to remove the EDDS from the Soil Washing solutions. Ecotoxicological tests, using different living organisms (Daphnia magna, Vibrio fischeri, Pseudokirchneriella subcapitata and Lepidium sativum), were performed on the Soil Washing effluents before and after the treatments to assess the effects of the proposed combined process on the ecotoxicity of the Soil Washing solutions.
Kwaihing Chan - One of the best experts on this subject based on the ideXlab platform.
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the mechanism of the surfactant aided Soil Washing system for hydrophobic and partial hydrophobic organics
Science of The Total Environment, 2003Co-Authors: Kwaihing ChanAbstract:A surfactant-aided Soil Washing mechanism is proposed in this study by examining nine common organic contaminants, which were divided into two groups, hydrophobic compounds and partial hydrophobic compounds, depending on the respective Soil partitioning of contaminants, Koc. The presence of a free non-aqueous phase liquid in the Soil Washing system is critical to determine the Soil Washing performance curves. A mathematical model is proposed to describe Soil-Washing performance at various surfactant concentrations. The resulting slopes and intercepts from the model for the performance prediction are linearly related to Koc. In addition, a transition zone between the hydrophobic and partial hydrophobic compounds was observed, and has been used in verifying the proposed mechanism successfully by overdosing and underdosing the contaminants in the system.
