Alkali activation as new option for gold mine tailings inertization

Kiventerä, Jenni; Lancellotti, Isabella; Catauro, Michelina; Poggetto, Francesco Dal; Leonelli, Cristina; Illikainen, Mirja

doi:10.1016/j.jclepro.2018.03.182

Cited by 156 publications

(61 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, after activation (P0), the increase in As solubility was very significant, surpassing not only the inert limit but also the non-hazardous limit. The difficulty in fixating As ions in aluminosilicate matrixes is well known [54,56], although this behaviour tends to improve with time [38,57]. It is related with the oxidation of the As ion, capable of assuming different oxyanoin forms, which possess very high solubility in alkaline environments but, nevertheless, are not bound to the final aluminosilicate matrix [57].…”

Section: Discussionmentioning

confidence: 99%

“…Although many of the above-mentioned studies were dealing with tailings resulting from tungsten and gold mines, several studies have also been produced targeting copper mine tailings [16,[19][20][21][22][23]. From an environmental perspective, it is important to highlight that alkaline activation has already proved to be very effective for containing and neutralising different types of wastes [24][25][26][27][28][29][30][31][32][33][34][35] and, specifically, wastes resulting from mine operations [36][37][38][39], a capacity that reinforces the potential for this technique to stabilise mine tailings.Nevertheless, a decisive breakthrough has yet to be achieved, one might say. Alkali activation for mine tailings stabilisation, for an industrial application or landfilling, is not yet a common option because of the logistical difficulties associated with the implementation of such an operation.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Recycling and Application of Mine Tailings in Alkali-Activated Cements and Mortars—Strength Development and Environmental Assessment

et al. 2020

View full text Add to dashboard Cite

Mine tailings (MT) could represent a step forward in terms of the quality of the aggregates usually used in civil engineering applications, mostly due to its high density. The Portuguese Neves Corvo copper mine, owned by the Lundin Mining Corporation, produces approximately 3 million tonnes per year. Nevertheless, it cannot be used in its original state, due to its high levels of sulphur and other metals (As, Cr, Cu, Pb, Zn). This paper focuses on the stabilisation/solidification of high-sulphur MT, without any previous thermal treatment, using alkali-activated fly ash (FA). The variables considered were the MT/FA ratio and the activator type and concentration. A fine aggregate was then added to the pastes to assess the quality of the resulting mortar. Maximum compressive strengths of 14 MPa and 24 MPa were obtained for the pastes and mortars, respectively, after curing for 24 h at 85 • C. Thermogravimetric analysis, scanning electron microscopy, X-ray energy dispersive spectroscopy, X-ray diffraction, and infrared spectroscopy were used to characterize the reaction products, and two types of leaching tests were performed to assess the environmental performance. The results showed that the strength increase is related with the formation of a N-A-S-H gel, although sodium sulphate carbonate was also developed, suggesting that the total sodium intake could be optimized without strength loss. The solubility of the analysed metals in the paste with 78% MT and 22% FA was below the threshold for non-hazardous waste. potential use of MT as a replacement for natural aggregates, which are usually obtained through an extraction process that severely affects the environment, would not only reduce the consumption of natural resources but also decrease the volume of landfilled MT. However, this waste generates acid mine drainage when exposed to oxygen and water [5], which makes it impractical as an aggregate in common applications, like embankments or roads, if not previously stabilised.Another possible use is inclusion in alkali-activated mortar and concrete, a recent research topic, with promising results in terms of mechanical and environmental performance [5,6]. Some studies focused on the use of MT as a precursor, albeit requiring a previous thermal treatment [7][8][9][10][11], while others used a different approach by considering the MT as a filler and/or coarse aggregate in composite materials, cemented by aluminosilicate gel formed from the alkali activation of fly ash, metakaolin, waste glass, or slags [11][12][13][14][15][16][17][18][19]. Although many of the above-mentioned studies were dealing with tailings resulting from tungsten and gold mines, several studies have also been produced targeting copper mine tailings [16,[19][20][21][22][23]. From an environmental perspective, it is important to highlight that alkaline activation has already proved to be very effective for containing and neutralising different types of wastes [24][25][26][27][28][29][30][31][32][33][34][35] and, specifically, wastes resulting from m...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Recycling and Application of Mine Tailings in Alkali-Activated Cements and Mortars—Strength Development and Environmental Assessment

et al. 2020

View full text Add to dashboard Cite

show abstract

“…When the amount of fly ash is fixed, the ratio of water to the mixture is greater, the strength of the grouting stones is slightly reduced within 12 hours, and the strength changes little after 1 day, indicating that the water content has a small effect on the strength of the material. e main reason was that the gels of the materials were not because of the hydration reaction of the traditional materials, but the reaction of the geopolymer under the alkali activation [17][18][19][20][21][22], which is less affected by the water content. 2 Advances in Materials Science and Engineering According to the above analysis, there are two characteristics of the new environmental protection grouting material: (1) early strength; (2) strength.…”

Section: Strengthmentioning

confidence: 99%

Development and Field Test of New Environmentally Friendly Water-Rich Sand Grout Material

Wang

Liu

Zhang

2019

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

e water-rich sand layer is a common source for underground engineering disasters. Considering the poor performance, high cost, and serious environmental pollution of conventional grouting materials, based on the requirements of environmental grouting treatment, a new type of environmental water-rich sand grouting material was proposed, which was mainly based on fly ash and cement and supplemented by water glass. e performance of the slurry was studied. e parameters such as the initial set time, the ratio of stone, and the compressive strength of the material under different water contents and fly ash contents were determined by experiments. e new grouting material was obtained with rapid setting, early strength, high ratio of stone formation, and strength, which were less affected by water content. e successful application of the new environmental grouting material in the Qingdao Metro not only ensures the safety of the project but also meets the requirements of environmental protection. It also verifies the scientificity of the material and will be useful for the innovation of the water-rich sand grouting material.

show abstract

“…Also, there are emerging innovative strategies able to immobilize the remain contents of toxic metals in construction materials production, such as alkali activation (Kiventerä et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

“…Also, since ChCl:MA is less viscous, it may have facilitated the movement of species between compartments, improving the migration ratios.These results proved the feasibility of coupling DES and ED to isolate As and W from mining residues in the anode compartment, from where they can be recovered. At the same time, the treated mining residues in the cathode compartment may be further used in construction materials, replacing conventional raw materials with economic and environmental benefits.Although the final residue is still not free of pollutants, leaching phenomena of harmful elements may be avoided with the studied treatment since the elements can be encapsulated.Also, there are emerging innovative strategies able to immobilize the remain contents of toxic metals in construction materials production, such as alkali activation (Kiventerä et al, 2018).…”

mentioning

confidence: 99%

Electrodialytic removal of tungsten and arsenic from secondary mine resources — Deep eutectic solvents enhancement

Almeida

Craveiro

Faria

et al. 2020

Science of The Total Environment

View full text Add to dashboard Cite

Please cite this article as: J. Almeida, R. Craveiro, P. Faria, et al., Electrodialytic removal of tungsten and arsenic from secondary mine resources -Deep eutectic solvents enhancement, Science of the Total Environment (2018), https://doi..pt (A. B. Ribeiro) HIGHLIGHTS  Proof of concept in coupling DES + ED for As and W removal from mining residues  Best As and W extraction achieved with ChCl:MA (1:2) and ChCl:OA (1:1)  DES and electrical current use improved extraction for As (22 %) and W (11 %)  From total As and W extracted, electromigration achieved 82 % for As and 77 % for W Journal Pre-proof J o u r n a l P r e -p r o o f 2 ABSTRACTTungsten is a critical raw material for European and U.S. economies. Tungsten mine residues, usually considered an environmental burden due to e.g. arsenic content, are also secondary tungsten resources. The electrodialytic (ED) process and deep eutectic solvents (DES) have been successfully and independently applied for the extraction of metals from different complex environmental matrices. In this study a proof of concept demonstrates that coupling DES in a two-compartment ED set-up enhances the removal and separation of arsenic and tungsten from Panasqueira mine secondary resources. Choline chloride with malonic acid (1:2), and choline chloride with oxalic acid (1:1) were the DES that in batch extracted the average maximum contents of arsenic (16 %) and tungsten (9 %) from the residues. However, when ED was operated at a current intensity of 100 mA for 4 days, the extraction yields increased 22 % for arsenic and 11 % for tungsten, comparing to the tests with no current.From the total arsenic and tungsten extracted, 82 % and 77 % respectively were successfully removed from the matrix compartment, as they electromigrated to the anolyte compartment, from where these elements can be further separated. This achievement potentiates circular economy, as the final treated residue could be incorporated in construction materials production, mitigating current environmental problems in both mining and construction sectors. KeywordsCritical raw material, harmful compound, secondary resource, electro-based technology, choline chloride/malonic acid, choline chloride/oxalic acid Abbreviations Journal Pre-proof J o u r n a l P r e -p r o o f 3 "W" -Tungsten; "As" -Arsenic; "ED" -Electrodialytic; "DES" -Deep Eutectic Solvents; "ChCl:OA" -Choline Chloride/ Oxalic Acid; "ChCl:MA" -Choline Chloride/ Malonic Acid; "ChCl:LA" -Choline Chloride/ Latic Acid; "PA:U" -Propionic Acid/ Urea the individuals exposed (Coelho et al., 2014).The electrodialytic (ED) process is a treatment technology, that has been studied over the last three decades, to remove heavy metals from several environmental matrices: (1) soil (Ribeiro Journal Pre-proof W that electromigrated into the anode compartment (anolyte) were determined according to Eq. 3 (in section 2.3.3) and presented in Table 6. The high migration percentages were obtained with ChCl:MA at 100 mA for As (82.3 ± 1.3 %) and 50 mA for W (76.5 ± 8.6 %).This ...

show abstract

Alkali activation as new option for gold mine tailings inertization

Cited by 156 publications

References 42 publications

Recycling and Application of Mine Tailings in Alkali-Activated Cements and Mortars—Strength Development and Environmental Assessment

Recycling and Application of Mine Tailings in Alkali-Activated Cements and Mortars—Strength Development and Environmental Assessment

Development and Field Test of New Environmentally Friendly Water-Rich Sand Grout Material

Electrodialytic removal of tungsten and arsenic from secondary mine resources — Deep eutectic solvents enhancement

Contact Info

Product

Resources

About