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21 results on '"Vassilieva, Elvira"'

12. Heavy metals in industrial sludge: Occurrence, Leaching behavior and Environmental implications

Author

Dung, Ta Thi Thu, Vassilieva, Elvira, Golheiran, Asefeh, Phung, Nguyen Ky, Swennen, Rudy, and Cappuyns, Valérie

Subjects
leaching, sludge, speciation, heavy metals
Abstract

Industrial activities generate different types of waste, with varying chemical properties. An investigation of the detailed chemical and mineralogical characteristics of these materials may serve as a first step for selecting an appropriate treatment or safe disposal method. This study focuses on arsenic (As) and heavy metals (i.e., Cd, Co, Cu, Cr, Mo, Ni, Pb, and Zn) in three sludge samples derived from industrial wastewater treatment plants in Southern Vietnam. The emphasis is on determining the influence of changing environmental conditions on element mobilization based on a multidisciplinary approach using sample micro analysis (Field Emission Gun Electron Probe Micro Analysis (FEG-EPMA)) in combination with different types of leaching/extraction tests. ispartof: pages:107-108 ispartof: Interfaces Against Pollution -Environmental Challenges & Opportunities- Book of abstracts pages:107-108 ispartof: Interfaces Against Pollution (IAP 2016) location:Lleida (Spain) date:4 Sep - 7 Sep 2016 status: published

Published
2016

13. Solid-phase characterization of blasted copper slag in relation to the potential release of toxic elements

Author

Dung, Tran Thi Thu, Cappuyns, Valérie, Vassilieva, Elvira, Golreihan, Asefeh, Phung, Nguyen Ky, Swennen, Rudy, Malfliet, Annelies, and Pontikes, Yiannis

Abstract

After being used as an abrasive agent, copper slag is considered a solid waste in Vietnam because appropriate waste treatment techniques and effective management options are not available. This classification as solid waste is mainly due to the fact that the blasted copper slag (BCS) contain impurities of potentially toxic elements (PTEs), such as As, Cd, Co, Cr, Cu, Mo, Ni, Pb, and Zn that can be released into environment. The present study was conducted with the aim to characterize the solid phase composition of blasted copper slag (BCS) and to investigate the leaching of PTEs from BCS under influence of pH. A wide pH range (1-10) was investigated in order to assess the environmental implications of different management scenarios. Besides amorphous phases, fayalite, magnetite, maghemite, quartz and elemental copper were the main minerals identified by X-ray diffraction (XRD). Field Emission Gun Electron Probe Micro Analysis (FEG-EPMA) results indicated that BCS mainly consisted of Fe, O and Si with minor amounts of S whereas the copper bearing phase was composed of Cu, Pb, and S with small amounts of Si. This indicates that copper in BCS was present not only in metallic phases but also in association with S in the form of sulphides (sulphides of Cu, Cu-Pb, Cu-Pb-Zn). Mapping of selected areas in thin sections with wavelength dispersive spectrometry also confirmed the presence of these sulphide phases which were not detected by XRD. Among the examined PTEs, Cr was found in Fe-O rich phases, while Mo was observed in a glass inclusion. These This might explain the low leachability of these elements in neutral pH conditions. Leaching tests indicated that most of the PTEs showed a low environmental concern in the neutral-alkaline pH range due to the low concentrations in the leachate compared to EU leaching limit value for non-hazardous waste, except As which exceeded this threshold at pH 10. Moreover, in the case of acidification (e.g. as a results of co-disposal with acid waste or as a result of acid rain), special attention should be paid to Cu and Zn which exhibit an important release at pH 3-5. On the other hand, recovery of Cu by acid treatment of the slag could be considered since an extraction with HNO3 1 M during 24 h showed that 39 % of the total Cu content (or 3369 mg/kg) was released from the slag. The feasibility of Cu recovery from the slag should be further investigated. no issn ispartof: pages:155-159 ispartof: Proceedings of the fourth International Slag Valorization Symposium vol:4 pages:155-159 ispartof: Slag Valorization Symposium location:Leuven date:15 Apr - 17 Apr 2015 status: published

Published
2015

15. pH dependent leaching behavior of Zn, Cd and Pb from slags: kinetics and mineralogical control

Author

Cappuyns, Valérie, Alian, Vajiheh, Vassilieva, Elvira, and Swennen, Rudy

Subjects
XRD, pHstat, mining, heavy metals, environmental impact, slag
Abstract

From the Middle Ages until the beginning of the 20th century, extensive Zn-Pb mining and smelting was carried out in East-Belgium. By lack of waste treatment techniques and sustainable management practices, metal-bearing slags and unprocessed waste were dumped in huge tailings, which still represent an important source of contamination. A chemical and mineralogical characterization of different types of mining waste originating from the former Pb-Zn mining industry was performed in order to gain a better understanding of the slag properties, with special attention to heavy metal release under varying pH conditions, and to bring this in relation to different management scenarios. ispartof: Waste and Biomass Valorization vol:5 issue:3 pages:355-368 status: published

Published
2014

16. INVESTIGATION OF POTENTIAL LEACHABILITY OF ARSENIC AND HEAVY METALS FROM BLASTED COPPER SLAG AND CONTAMINATED MARINE SEDIMENTS BY SINGLE EXTRACTIONS IN SOUTH OF VAN PHONG BAY – VIETNAM

Author

Dung, Tran Thi Thu, Cappuyns, Valérie, Swennen, Rudy, Vassilieva, Elvira, and Phung, Nguyen Ky

Subjects
leaching, sediments, copper slag
Abstract

Copper slag is widely used as abrasive material for removing rust and marine deposits from ships to prepare the surface before painting. Development of shipping industry has raised an environmental concern related to the release of heavy metal from blasted copper slag in Vietnam. This study was conducted to investigate the characteristics of the blasted copper slag (BCS) and potentially contaminated sediment samples collected nearby the shipyard in south of Van Phong bay (south-central of Vietnam). Single extractions (with CaCl2, (NH4)2EDTA, CH3COOH and NaCl) were performed to examine under which conditions As and heavy metals (HMs) may leach from the BCS and sediment. The BCS samples were mainly composed of Fe, Ca, Al and Si (percentage levels). Furthermore, BCS contained significant amounts of Cu, Zn (8416 and 8439 mg/kg respectively) and Mo, Pb, As, Cr (2399, 853, 798 and 566mg/kg respectively). Results from the single extractions suggest that As and HMs in both sediments and BCS showed a low actual mobility and were not easily mobilized by sea water and/or organic complexion. Acidification had a more pronounced effect on As and HM release both in sediments and BCS ispartof: pages:299-308 ispartof: Proceeding of the international conference on “Bien Dong 2012" pages:299-308 ispartof: international conference on “Bien Dong 2012” location:Nha Trang date:12 Sep - 14 Sep 2012 status: published

Published
2013

17. Release of Potentially Toxic Elements From Industrial Sludge: Implications for Land Disposal.

Author

Dung, Tran Thi Thu, Cappuyns, Valérie, Vassilieva, Elvira, Golreihan, Asefeh, Phung, Nguyen Ky, and Swennen, Rudy

Subjects
SEWAGE sludge, SEWAGE disposal, SLUDGE composting, INDUSTRIAL contamination, FACTORY sanitation
Abstract

In recent years, rapid industrial development has led to an increase in various types of industrial waste generation in Vietnam. Potentially toxic elements (PTEs) can contaminate water resources when waste is not properly treated and/or stored in confined disposal facilities. This study characterizes the occurrence and leaching behavior of PTEs from industrial sludge under the influence of oxidation and pH with implications for open dump disposal. Environmental issues related to possible management options are also addressed. Sludge samples from industrial parks at Binh Duong and Dong Nai, Southern Vietnam, were oxidized under atmospheric conditions. The results indicate that Fe and Mn (both samples) and Cu, Ni, and Zn (Binh Duong sample) may pose a potential threat to the water quality for sludge dumped near water bodies. Therefore, we recommend avoiding uncontrolled upland disposal of such sludge. Some preliminary treatment to immobilize PTEs should be applied to the sludge originating from Binh Duong prior to upland disposal. A recovery of Ni and Zn from this sludge could be considered. For the less contaminated sludge from Dong Nai, beneficial use, such as land application for agricultural purposes, is a possible option. [ABSTRACT FROM AUTHOR]

Published
2015
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18. Insights into solid phase characteristics and release of heavy metals and arsenic from industrial sludge via combined chemical, mineralogical, and microanalysis.

Author

Dung, Tran, Golreihan, Asefeh, Vassilieva, Elvira, Phung, Nguyen, Cappuyns, Valérie, and Swennen, Rudy

Subjects
HEAVY metals, MICROCHEMISTRY, SEWAGE, POLLUTION, ENVIRONMENTAL sciences
Abstract

This study investigates the solid phase characteristics and release of heavy metals (i.e., Cd, Co, Cu, Cr, Mo, Ni, Pb, and Zn) and arsenic (As) from sludge samples derived from industrial wastewater treatment plants. The emphasis is determining the influence of acidification on element mobilization based on a multidisciplinary approach that combines cascade and pH leaching tests with solid phase characterization through X-ray diffraction (XRD), field emission gun electron probe micro analysis (FEG-EPMA), and thermodynamic modeling (Visual MinteQ 3.0). Solid phase characterization and thermodynamic modeling results allow prediction of Ni and Zn leachabilities. FEG-EPMA is useful for direct solid phase characterization because it provides information on additional phases including specific element associations that cannot be detected by XRD analysis. Cascade and pH leaching test results indicate that disposal of improperly treated sludges at landfills may lead to extreme environmental risks due to high leachable concentrations of Zn, Ni, Cu, Cr, and Pb. However, high leachabilities under acid conditions of Ni and Zn as observed from pH leaching test results may provide a potential opportunity for acid extraction recovery of Ni and Zn from such sludges. [ABSTRACT FROM AUTHOR]

Published
2015
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19. Assessment on Pollution by Heavy Metals and Arsenic Based on Surficial and Core Sediments in the Cam River Mouth, Haiphong Province, Vietnam.

Author

Ho, HuuHieu, Swennen, Rudy, Cappuyns, Valérie, Vassilieva, Elvira, Neyens, Gerda, Rajabali, Mustafa, and Van Tran, Tan

Subjects
HEAVY metal toxicology, ARSENIC, SOIL composition, SEDIMENTS, WATER supply
Abstract

The Cam River mouth (Haiphong Province) is one of the main river mouths of the Red River System, which is one of the most important water resources in Northern Vietnam. Over the past 50 years, the strong socio-economic development in the area has caused a considerable contamination with heavy metals (Co, Cr, Cu, Mn, Ni, Pb, and Zn) and arsenic. In this study, the vertical and horizontal distributions of heavy metals and arsenic in sediments from the Cam River mouth were investigated. In addition, the history, origin, and degree of contamination were assessed. Normalized (with respect to Al) heavy metal and arsenic concentrations in sediment cores and absolute dates obtained from the137Cs analysis were used to reconstruct the pollution history of the river mouth. As, Cu, Mn, Pb, and Zn concentrations increase rapidly by approximately two times or more from 1954 to 1975, and then remain nearly unchanged from 1975 until 2008, whereas Co, Cr, and Ni concentrations slightly increase from 1954 until 2008. In addition, background values for heavy metals and arsenic have also been determined with regard to the period before 1954. In the study area, Co, Cr, Cu, Ni, Mn, and Zn are evaluated as minorly enriched, whereas As and Pb are classified as moderately enriched. Generally, the anthropogenic activities in the Haiphong harbor and industrial zone locally contribute to the contamination by heavy metals and arsenic in the Cam River mouth. [ABSTRACT FROM PUBLISHER]

Published
2013
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21. Origin of the saline paleofluids in fault-damage zones of the Jabal Qusaybah Anticline (Adam Foothills, Oman): Constraints from fluid inclusions geochemistry.

Author

Mozafari, Mahtab, Swennen, Rudy, Muchez, Philippe, Vassilieva, Elvira, Balsamo, Fabrizio, Storti, Fabrizio, Pironon, Jacques, and Taberner, Conxita

Subjects
*FLUID inclusions, *CENOZOIC stratigraphic geology, *CALCITE analysis, *GEOCHEMISTRY
Abstract

The Jabal Qusaybah Anticline, in north Oman, is affected by syn-folding strike-slip and extensional fault zones developed during foreland deformation ahead of the Northern Oman Mountains thrust wedge, in Cenozoic times. Migration of fluids in fault-damage zones is recorded in complex calcite vein networks. By employing the microthermometric and compositional microanalysis of the fluid inclusions (crush-leach), two distinct generations of veins have been studied. The aim was to determine the source of elevated salinity in fluids involved in their cementation and explain their compositional evolution through fluid-rock interactions. The ionic ratios (Na/Br and Cl/Br) obtained from crush-leach analysis give supporting evidence that the elevated salinity of fluid inclusions in both vein groups originated from an evaporated seawater beyond the onset of halite precipitation (residual brines). The results reveal a gradual increase in salinity of the fluids, F/Cl molar ratios, as well as Li/Cl molar ratios. These results imply the progressively increasing contribution of evaporitic residual brines and fluids that interacted with, or were derived from siliciclastic rocks. We suggest that the most likely origin of the former fluids is provided by residual brines associated with precipitation of the Ara evaporites (Cambrian). The regional driving mechanism for such a significant fluid migration is believed to be compaction-driven upward flow that was channeled into faults and fractures during major deformational events. [ABSTRACT FROM AUTHOR]

Published
2017
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