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Jen-how Huang - One of the best experts on this subject based on the ideXlab platform.
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leaching characteristics of vanadium in Mine Tailings and soils near a vanadium titanomagnetite mining site
Journal of Hazardous Materials, 2014Co-Authors: Jinyang Yang, Ya Tang, Kai Yang, Ashaki A. Rouff, Evert J. Elzinga, Jen-how HuangAbstract:A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of vanadium in a Panzhihua soil and vanadium titanomagnetite Mine Tailings. Results from sequential extraction experiments indicated that the mobility of vanadium in both the soil and the Mine Tailings was low, with <1% of the total vanadium readily mobilised. Column experiments revealed that only <0.1% of vanadium in the soil and Mine tailing was leachable. The vanadium concentrations in the soil leachates did not vary considerably, but decreased with the leachate volume in the Mine tailing leachates. This suggests that there was a smaller pool of leachable vanadium in the Mine Tailings compared to that in the soil. Drought and rewetting increased the vanadium concentrations in the soil and Mine tailing leachates from 20 μg L−1 to 50–90 μg L−1, indicating the potential for high vanadium release following periods of drought. Experiments with soil columns overlain with 4, 8 and 20% volume Mine Tailings/volume soil exhibited very similar vanadium leaching behaviour. These results suggest that the transport of vanadium to the subsurface is controlled primarily by the leaching processes occurring in soils.
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Leaching characteristics of vanadium in Mine Tailings and soils near a vanadium titanomagnetite mining site.
Journal of Hazardous Materials, 2013Co-Authors: Jinyang Yang, Ya Tang, Kai Yang, Ashaki A. Rouff, Evert J. Elzinga, Jen-how HuangAbstract:A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of vanadium in a Panzhihua soil and vanadium titanomagnetite Mine Tailings. Results from sequential extraction experiments indicated that the mobility of vanadium in both the soil and the Mine Tailings was low, with
Yuehua Hu - One of the best experts on this subject based on the ideXlab platform.
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a review on in situ phytoremediation of Mine Tailings
Chemosphere, 2017Co-Authors: Li Wang, Bin Ji, Yuehua HuAbstract:Abstract Mine Tailings are detrimental to natural plant growth due to their physicochemical characteristics, such as high pH, high salinity, low water retention capacity, high heavy metal concentrations, and deficiencies in soil organic matter and fertility. Thus, the remediation of Mine Tailings has become a key issue in environmental science and engineering. Phytoremediation, an in situ cost-effective technology, is emerging as the most promising remediation method for Mine Tailings by introducing tolerant plant species. It is particularly effective in dealing with large-area Mine Tailings with shallow contamination of organic, nutrient and metal pollutants. In this review, the background, concepts and applications of phytoremediation are comprehensively discussed. Furthermore, proper amendments used to improve the physical, chemical and biological properties of Mine Tailings are systematically reviewed and compared. Emphasis is placed on the types and characteristics of tolerant plants and their role in phytoremediation. Moreover, the role of microorganisms and their mechanism in phytoremediation are also discussed in-depth.
Monica O Mendez - One of the best experts on this subject based on the ideXlab platform.
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phytostabilization of Mine Tailings in arid and semiarid environments an emerging remediation technology
Environmental Health Perspectives, 2008Co-Authors: Monica O Mendez, Raina M MaierAbstract:Mine Tailings disposal sites from either inactive or abandoned Mine sites are prevalent in arid and semiarid regions throughout the world. Major areas include northern Mexico and the Western United States, the Pacific coast of South America (Chile and Peru), southwestern Spain, western India, South Africa, and Australia (Munshower 1994; Tordoff et al. 2000). The global impact of such Mine Tailings disposal sites is enormous, as unreclaimed mining sites generally remain unvegetated for tens to hundreds of years, and exposed Tailings can spread over tens of hectares via eolian dispersion and water erosion [Gonzalez and Gonzalez-Chavez 2006; Morris et al. 2003; Munshower 1994; U.S. Environmental Protection Agency (U.S. EPA) 2004; Warhurst 2000]. Mine Tailings, or mill Tailings, are the materials remaining after extraction and beneficiation of ores. What prevents the natural revegetation of Mine Tailings? It is generally a combination of factors beginning with metal toxicity. Tailings are characterized by elevated concentrations of metals such as arsenic, cadmium, copper, manganese, lead, and zinc (1–50 g/kg) (Boulet and Larocque 1998; Bradshaw et al. 1978; Walder and Chavez 1995). Further, Tailings contain no organic matter or macronutrients, and usually exhibit acidic pH, although some Tailings may be alkaline (Johnson and Bradshaw 1977; Krzaklewski and Pietrzykowski 2002). For these reasons, Tailings remain without normal soil structure and support a severely stressed heterotrophic microbial community (Mendez et al. 2007; Southam and Beveridge 1992). Hence, the microbial community is extremely low in species richness and carbon utilization diversity compared with uncontaminated soil (Moynahan et al. 2002). Furthermore, autotrophic iron- and sulfur-oxidizing bacteria dominate the microbial community in Mine Tailings and are associated with plant death in acidic Tailings (Schippers et al. 2000). In arid and semiarid regions, plant establishment on Mine Tailings is further impeded by a number of physicochemical factors including extreme temperatures especially at the Tailings surface, low precipitation, and high winds. These factors contribute to the development of extremely high salt concentrations ranging up to 22 dS/m due to high evaporation and low water infiltration (Munshower 1994).
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plant growth promoting bacteria for phytostabilization of Mine Tailings
Environmental Science & Technology, 2008Co-Authors: Christopher J Grandlic, Monica O Mendez, Jon Chorover, Blenda Machado, Raina M MaierAbstract:Eolian dispersion of Mine Tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to enhance the revegetation of Mine Tailings and minimize the need for compost amendment. Twenty promising PGPB isolates were used as seed inoculants in a series of greenhouse studies to exaMine revegetation of an extremely acidic, high metal content Tailings sample previously shown to require 15% compost amendment for normal plant growth. Several isolates significantly enhanced growth of two native species, quailbush and buffalo grass, in Tailings. In this study, PGPB/compost outcomes were plant specific; for quailbush, PGPB were most effective in combination with 10% compost addition while fo...
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phytoremediation of Mine Tailings in temperate and arid environments
Reviews in Environmental Science and Bio\ technology, 2008Co-Authors: Monica O Mendez, Raina Margaret MaierAbstract:Phytoremediation is an emerging technology for the remediation of Mine Tailings, a global problem for which conventional remediation technologies are costly. There are two approaches to phytoremediation of Mine Tailings, phytoextraction and phytostabilization. Phytoextraction involves translocation of heavy metals from Mine Tailings to the plant shoot biomass followed by plant harvest, while phytostabilization focuses on establishing a vegetative cap that does not shoot accumulate metals but rather immobilizes metals within the Tailings. Phytoextraction is currently limited by low rates of metal removal which is a combination of low biomass production and insufficiently high metal uptake into plant tissue. Phytostabilization is currently limited by a lack of knowledge of the minimum amendments required (e.g., compost, irrigation) to support long-term plant establishment. This review addresses both strategies within the context of two specific climate types: temperate and arid. In temperate environments, Mine Tailings are a source of metal leachates and acid Mine drainage that contaminate nearby waterways. Mine Tailings in arid regions are subject to eolian dispersion and water erosion. Examples of phytoremediation within each of these environments are discussed. Current research suggests that phytoextraction, due to high implementation costs and long time frames, will be limited to sites that have high land values and for which metal removal is required. Phytostabilization, due to lower costs and easier implementation, will be a more commonly used approach. Complete restoration of mining sites is an unlikely outcome for either approach.
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phytostabilization potential of quailbush for Mine Tailings growth metal accumulation and microbial community changes
Journal of Environmental Quality, 2007Co-Authors: Monica O Mendez, Edward P Glenn, Raina M MaierAbstract:: Abandoned Mine Tailings sites in semiarid regions remain unvegetated for extended periods of time and are subject to eolian dispersion and water erosion. This study exaMines the potential phytostabilization of a lead-zinc Mine Tailings site using a native, drought-tolerant halophyte, quailbush [Atriplex lentiformis (Torr.) S. Wats.]. In a greenhouse study germination, growth, and metal uptake was evaluated in two compost-amended Mine Tailings samples, K4 (pH 3) and K6 (pH 6) at 75, 85, 90, 95, and 100% Mine Tailings, and two controls, off-site and compost. Microbial community changes were monitored by performing MPN analysis of iron- and sulfur-oxidizing bacteria as well as heterotrophic plate counts. Results demonstrate that germination is not a good indicator for phytostabilization since it was only inhibited in the unamended K4 treatment. Plant growth was significantly reduced in 95 and 100% Mine Tailings, while growth in 75, 85, and 90% treatments was similar to the off-site control. Quailbush accumulated elevated levels of the nutrient metals Na, K, Mn, and Zn in the shoot tissues; however, metal accumulation was generally below the domestic animal toxicity limit. Initially, autotrophic population estimates were four to six logs higher than heterotrophic counts, indicating extremely stressed conditions. However, post-harvest, heterotrophic bacterial counts increased to normal levels (approximately 10(6) CFU g-1 dry Tailings) and dominated the rhizosphere. Therefore, with compost amendment, quailbush has good potential as a native species candidate for phytostabilization of Mine Tailings in semiarid environments.
Jinyang Yang - One of the best experts on this subject based on the ideXlab platform.
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leaching characteristics of vanadium in Mine Tailings and soils near a vanadium titanomagnetite mining site
Journal of Hazardous Materials, 2014Co-Authors: Jinyang Yang, Ya Tang, Kai Yang, Ashaki A. Rouff, Evert J. Elzinga, Jen-how HuangAbstract:A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of vanadium in a Panzhihua soil and vanadium titanomagnetite Mine Tailings. Results from sequential extraction experiments indicated that the mobility of vanadium in both the soil and the Mine Tailings was low, with <1% of the total vanadium readily mobilised. Column experiments revealed that only <0.1% of vanadium in the soil and Mine tailing was leachable. The vanadium concentrations in the soil leachates did not vary considerably, but decreased with the leachate volume in the Mine tailing leachates. This suggests that there was a smaller pool of leachable vanadium in the Mine Tailings compared to that in the soil. Drought and rewetting increased the vanadium concentrations in the soil and Mine tailing leachates from 20 μg L−1 to 50–90 μg L−1, indicating the potential for high vanadium release following periods of drought. Experiments with soil columns overlain with 4, 8 and 20% volume Mine Tailings/volume soil exhibited very similar vanadium leaching behaviour. These results suggest that the transport of vanadium to the subsurface is controlled primarily by the leaching processes occurring in soils.
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Leaching characteristics of vanadium in Mine Tailings and soils near a vanadium titanomagnetite mining site.
Journal of Hazardous Materials, 2013Co-Authors: Jinyang Yang, Ya Tang, Kai Yang, Ashaki A. Rouff, Evert J. Elzinga, Jen-how HuangAbstract:A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of vanadium in a Panzhihua soil and vanadium titanomagnetite Mine Tailings. Results from sequential extraction experiments indicated that the mobility of vanadium in both the soil and the Mine Tailings was low, with
Mirja Illikainen - One of the best experts on this subject based on the ideXlab platform.
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Influence of Calcined Mine Tailings on the Properties of Alkali Activated Slag Mortars
Key Engineering Materials, 2020Co-Authors: Łukasz Kotwica, Marcin Chorembała, Ewa Kapeluszna, Jan Deja, Piotr Chęciński, Mirja Illikainen, Łukasz GołekAbstract:Influence of copper Mine Tailings on properties of soda activated ground granulated blast furnace slag mortars and pastes was investigated. Calcination of copper Mine Tailings was found to be a method of increasing their pozzolanic activity. Material calcined at 750°C possessed highest pozzolanic activity. So obtained material can be used as a partial substitution of ground granulated slag in soda activated blends. Introduction of calcined copper Mine Tailings decrease strength up to 28 days, but after 56 days strength results are similar or even higher comparing to control samples. Phase composition of hydrated material is not affected significantly by the presence of calcined copper Mine Tailings.
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Utilization of sulphidic Mine Tailings in alkali-activated materials
MATEC Web of Conferences, 2019Co-Authors: Jenni Kiventerä, Jan Deja, Juho Yliniemi, Lukasz Golek, Victor M. Ferreira, Mirja IllikainenAbstract:Disposal of Mine Tailings is one of the most important environmental issues during the mining lifetime. Especially sulphidic Tailings can cause environmental and ecological risks because of their tendency to oxidize in the presence of water or air. Because of small particle size and harmful chemical properties, utilization possibilities of sulphidic Mine Tailings are limited. The aim of the present study was to develop technologies to utilize sulphidic Mine Tailings in alkali activated materials. Alkali-activated materials also known as geopolymers are nanosized zeolite type or slightly amorphous materials comparable to traditional Portland cement concrete, which can physically encapsulate or chemically stabilize the hazardous elements such as heavy metals into the 3D structure. Mine tailing based geopolymer aggregates were successfully produced from sulphidic Mine Tailings with good physical properties. The geopolymer aggregates performed as a concrete aggregate comparable to commercial lightweight aggregates. In addition, geopolymer mortars were prepared from Mine Tailings. In mortar application, there is a need to add some co-binder such as blast furnace slag in order to achieve high strength for the material. The Mine tailing based geopolymer structure has an ability to stabilize a large number of cationic species into the structure while some anionic species were not able to immobilize by alkaline activation.
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alkali activation as new option for gold Mine Tailings inertization
Journal of Cleaner Production, 2018Co-Authors: Jenni Kiventerä, Isabella Lancellotti, Michelina Catauro, Francesco Dal Poggetto, Cristina Leonelli, Mirja IllikainenAbstract:Abstract The mining industry produces a huge quantity of sulphidic Mine Tailings, which cause several short- and long-term environmental problems when disposed by landfilling in impounding lakes. The possibility of immobilizing several heavy metals from gold Mine Tailings by reactive geopolymerization technique has been investigated in the present study. The chemical stability of geopolymers synthetized by the alkali activation of metakaolin and blast furnace slag and the addition of 40–50 wt% gold Mine Tailings is demonstrated. The geopolymers were cured at room temperature, and the effects of different Si/Al and Na/Al molar ratios and curing times were investigated. The inertization effectiveness was evaluated by means of leaching tests carried out according to standard EN 12457 after 7 and 28 days and after 18 months. The samples were immersed into the water for 1 day, and the leachable metals in the test solution were deterMined by ICP-OES. The results show that various elements (Cr, Cu, Ni, Zn and Mn) from gold Mine Tailings are able to immobilize almost completely by alkali activation with proper co-binder material. The immobilization efficiency were highly improved with longer curing period also for the problematic elements As, V, Sb and B.
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recycling Mine Tailings in chemically bonded ceramics a review
Journal of Cleaner Production, 2018Co-Authors: Paivo Kinnunen, Arnold Ismailov, Soili Solismaa, Harisankar Sreenivasan, Marjaliisa Raisanen, Erkki Levanen, Mirja IllikainenAbstract:Abstract Mine Tailings account for most of the environmental incidents related to the extractive industry, with risks increasing due to steadily rising tonnage of low-grade ore and extreme weather events. Recycling of Tailings in raw-material-intensive applications presents an interesting alternative to costly Tailings management with associated restoration efforts. Chemically bonded ceramics may offer a route to upgrading Mine Tailings into raw materials for ceramics. In this review such chemically bonded ceramic methods that may be used to recycle Mine Tailings as raw materials, are reviewed while focusing in particular on two methods: 1) geopolymerization/alkali activation and 2) chemically bonded phosphate ceramics. The aim of the review is not to give exhaustive review on the wide topic, but to scope the required boundary conditions that need to be met for such utilization. According to the findings, alkali activation has been studied for 28 separate silicate Minerals in the scientific literature, and presents a viable method, which is already in commercial use in calcium-rich cement-like binder applications. Phosphate bonding literature is more focused on phosphate containing Minerals and waste encapsulation. Very little work has been done on low-calcium Tailings utilization with either technology, and more knowledge is needed on the effect of different pre-treatment methods to increase reactivity of Mine Tailings in chemically bonded ceramics.