Type Of Tailings Research Articles

Use and Recovery of Extractive Waste and Tailings for Sustainable Raw Materials Supply

Extractive waste (EW), including tailings, is produced in large quantities during mining activities. In recent years, the linear economic model (“take-use-and-throw” approach) has been replaced by a circular approach, emphasizing the sustainable use and recovery of EW. The development of innovative protocols, such as Best Available Techniques (BATs), which aim at the technological and process improvement of more sustainable mining activities and at the production of renewable, highly performing green materials, has led to technological advancements, expertise in sustainability, and a reduced ecological footprint, potentially causing positive economic and social impacts and reducing environmental ones. Extractive waste and tailings, if suitably characterized, can be used to improve and make sustainable the works connected to the management of mining activities. The qualitative–quantitative characterization of EW is essential for subsequent reuse and for assessing the risk to human health and the extent of environmental impacts in the various matrices. The application areas vary according to the type of waste and mining tailings, the morphological characteristics of the deposits, and the geological, geomorphological, and logistic context of the area. Integrated protocols for sustainable EW exploitation and positive impacts on the economic, environmental, and technological/social level are analyzed. The present paper aims at providing an overview of challenges and potentialities connected to extractive waste (EW) management and potential exploitation to recover raw materials (RM), critical raw materials (CRM), and secondary raw materials (SRM).

Gold and Iron Tailings to Improve the Compressive Strength and Workability of Concrete

This scientific study aims to determine the optimal replacement percentage of mine tailings as a substitute for fine aggregate to improve both the compressive strength and the workability of the concrete, both in the case of gold mine tailings and gold mine tailings iron. It is a documentary, bibliographical and descriptive investigation that follows a deductive method with a quantitative approach. In addition, it is descriptive, correlational, and explanatory, with a descriptive level and a non-experimental, longitudinal, and retrospective design. The results indicate that the incorporation of 15% gold mining tailings increases the compressive strength by 4,44% while incorporating 12% iron mining tailings increases the resistance to compression by 7,79%. Likewise, by adding 30% gold mining tailings, a notable increase of 74,36% in tensile strength is obtained. On the other hand, when 5% gold mine tailings are added, the slump remains at 4"; however, by increasing the addition to 10%, it decreases from 2" to 1.77". In the case of tailings iron miners incorporating 30% the settlement remains at 2"; but by increasing the amount to 12%, the slump decreases from 3.32" to 1.57". Finally, the study shows that using mine tailings as a substitute for fine aggregate can significantly improve the compressive strength and workability of concrete, depending on the type of tailings and its percentage of incorporation.

Comprehensive Utilization of Tailings in Quartz Vein-Hosted Gold Deposits

The aim of this study was to develop a comprehensive technology for the utilization of tailings from quartz vein-hosted gold deposits. We investigated the recovery potential and separation process for gold, feldspar, and quartz from tailings samples collected from the Jinqu gold mine in Henan province, China. The sequence of the principal flowsheet of the comprehensive utilization of gold, feldspar, and quartz from the tailings samples was determined according to the process mineralogy and corresponding experiments. The residual gold in the tailings was extracted, and both feldspar and quartz concentrates were recovered according to the flowsheet of selective desliming, flotation of gold-bearing sulfide ore, removal of iron-containing impurities, flotation separation of feldspar, and purification of quartz. The quartz concentrate met China’s industrial standard for raw-material quartz sand for producing high-grade glass, such as cover glass for touch electronics and TFT LCD liquid crystal substrate glass. The feldspar concentrate also met China’s ceramic industry standards. The established process provides an efficient way for recovering the main valuable minerals in tailings from quartz vein-hosted gold deposits. Moreover, this study demonstrates the synthetic recovery of the same type of gold tailings.

Use of combined tools for effectiveness evaluation of tailings rehabilitated with designed Technosol.

Soil and water characteristics and biogeochemical processes can be improved by the application of an integrated technology based on circular economy: designed Technosol. The evaluation of the effectiveness of the superficial application of a designed Technosol, with andic and eutrophic properties, on the rehabilitation of sulfide tailings of a uranium mine (Fé mining area, Spain) was the aim of this study. After 20months of the Technosol application, the tailing rehabilitation status (Rehabilitated tailing) was compared to a non-rehabilitated tailing (Tailing). To assess the rehabilitation of these systems, several properties were analyzed: chemical characteristics of the materials and their leachates, soil enzymatic activities (dehydrogenase, β-glucosidase, acid phosphatase and urease), basal respiration and several plant endpoints from direct and indirect bioassays and pot experiment using Lolium perennse L. and Trifolium pratense L.. Potentially toxic concentrations of Co, Mn and Ni were identified in both available fraction and leachates, pointing out the serious environmental risk posed by the tailing. The improvement of overall physicochemical properties in the rehabilitated tailing materials (e.g., decrease of thehazardous element concentrations in leachates and available fraction, and improvement of thefertility and structure) allowed a quick plant cover with pasture species and provided a suitable habitat for active microbial community (evaluated by increasing dehydrogenase activity and basal respiration). This improvement in the rehabilitated tailing contributed to a significant decrease in the ecotoxicological risk and the spread of hazardous elements. The field application of this specific Technosol was a promising and lasting solution for rehabilitation of this type of tailings.

Non-isothermal evolution of mechanical properties, pore structure and self-desiccation of cemented paste backfill

In the field, cemented paste backfill (CPB) structures are subjected to non-isothermal curing conditions. In this study, the non-isothermal strength, pore structure development, and self-desiccation of CPB were investigated. CPB specimens with different types of binders and tailings were prepared and cured under isothermal (room temperature: 20 °C) and field non-isothermal conditions. Unconfined compressive strength (UCS) tests, microstructural tests and analyses as well as monitoring experiments, were conducted on CPB specimens cured over various ages. The obtained results show that the non-isothermal curing condition significantly increases the strength as well as the strength increase rate of the CPB regardless of the type of binder and tailings used. Moreover, the non-isothermal condition leads to more intense self-desiccation of CPB as well as the refinement of the pore structure of CPB due to the generation of more hydration products, such as calcium–silicate–hydrate (C–S–H), in the non-isothermal CPB. It is also found that a mine cavity (stope) backfilled with CPB material made with Portland cement type I (PCI) has a significant advantage over stope backfilled with CPB made with slag/PCI (50%/50%) in terms of strength formation and enhancement of self-desiccation due the difference in the non-isothermal curing conditions. The findings of this study provide insight into the development of the mechanical and microstructure properties as well as self-desiccation of CPB structures when exposed to field thermal curing condtions, thereby contributing to the improvement of mechanical stability and economic performance of future CPB designs. The impact of non-isothermal curing conditions on CPB properties need to be considered in mine backfill design and operations.

A Deep Look into the Microbiology and Chemistry of Froth Treatment Tailings: A Review.

In Alberta’s Athabasca oil sands region (AOSR), over 1.25 billion m3 of tailings waste from the bitumen extraction process are stored in tailings ponds. Fugitive emissions associated with residual hydrocarbons in tailings ponds pose an environmental concern and include greenhouse gases (GHGs), reduced sulphur compounds (RSCs), and volatile organic compounds (VOCs). Froth treatment tailings (FTT) are a specific type of tailings waste stream from the bitumen froth treatment process that contains bioavailable diluent: either naphtha or paraffins. Tailings ponds that receive FTT are associated with the highest levels of biogenic gas production, as diverse microbial communities biodegrade the residual diluent. In this review, current literature regarding the composition, chemical analysis, and microbial degradation of FTT and its constituents is presented in order to provide a more complete understanding of the complex chemistry and biological processes related to fugitive emissions from tailings ponds receiving FTT. Characterizing the composition and biodegradation of FTT is important from an environmental perspective to better predict emissions from tailings ponds and guide tailings pond management decisions.

Upcycling of mechanically treated silicate mine tailings as alkali activated binders

Mining activity is inevitable in human societies, and thus, disposal of mining waste in a proper and effective way is crucial to preserving our environment. In this context, studies on the reuse potential for mine tailings in the construction sector are booming. However, utilizing tailings as binder material is complicated due to the high variation in mineralogical composition and the low reactivity of these materials. In this study, an attempt was made to understand the effect of mechanical treatment on silicate mine tailings in order to improve their properties for use as a sole precursor in alkali-activated binders. Two different silicate tailings from Finland were studied: one rich in tremolite, which is high in magnesium (HM tailings) and one rich in anorthite and epidote, which is high in aluminum (HA tailings). Interestingly, grinding activity performed at different durations affected the properties of the tailings with various intensities, including their mineralogical and physical properties and characteristics and, thus the reactivity of tailings. Tremolite does not respond to milling for longer durations, and layered anorthite was easily distorted by the mechanical disturbance. Irrespective of the type of tailings, the compressive strength of alkali-activated milled tailings increased with an increase in grinding time from 1 to 16 min. However, the percentage of compressive strength increase varied with the type of tailings and their mineralogy.

KERUSAKAN LAHAN AKIBAT KEGIATAN PENAMBANGAN EMAS TANPA IZIN DISEKITAR SUNGAI SINGINGI KABUPATEN KUANTAN SINGINGI

Indonesia is one of the countries that has the potential of natural resources other than agriculture, namely mining, especially gold. Gold mining without permits is one of the mining activities which results in a decrease in the quality of the surrounding environment, especially land. The purpose of this study was to look at the land damage that occurred as a result of unlicensed gold mining activities around the Singingi River in the massive Kuantan Singingi Regency in the past two decades. The method used in the analysis is the scoring and overlay method, the data used are Landsat 5 TM and Landsat 8 OLI which are processed using the supervised cllasification method and digitized on screen. Furthermore, as comparative data, surveys and interviews are carried out and utilizing high resolution image data from SPOT images and google earth. The results of this study were found that there was a change in land use from other land uses into unlicensed gold mining land covering an area of 2,680.03 Ha from 2006 to 2018. Then a land damage map with three parameters was produced, namely vegetation density, mine life and type of tailings . Land with a high level of damage covering 699.34 ha, moderate damage 1,501.04 and low damage 479.65. The largest area of land damage occurs in Sungai Paku Village and the smallest village is Pulau Padang.

Mine tailing extraction indexes and model using remote-sensing images in southeast Hubei Province

Southeast Hubei province is an important iron–copper production base in China, which has produced a large number of mine tailings from mining activities. Although they contain a certain amount of iron or copper as secondary mineral resources, the mine tailings and related acid wastewater can lead to environmental pollution through sand blowing or seepage. For effective resource utilization and environmentally conscious development, rapid evaluations of the spatial distribution, type, and age of mine tailings are of national importance. Using spectral features, which are determined by the structure and composition of tailings, we develop an all-band tailing index, a modified normalized difference tailing index (MNTI), and a normalized difference tailings index for Fe-bearing minerals (NDTIFe). The all-band tailings index reflect the micro-structure and overall high reflectivity of mine tailings by comprehensively utilizing information from each band of Landsat 8 data. The MNTI and NDTIFe provide enhanced tailings composition information from the perspective of anion (carbanion and hydroxy) and cation (mainly ferric ion) contents, respectively. A tailing extraction model (TEM) is built using these three indexes to extract mine tailing information in Huangshi city. The TEM proposed in this paper can successfully and rapidly extract mine tailings information with an extraction precision of 84% in the research area.

Preparation and characterization of Portland cement clinker from iron ore tailings

We report a type of high-magnesium and low-silicon iron ore tailings (IOT) utilized as a raw material replacing clay to produce cement clinkers by conventional sintering process. Properties of the cement clinkers sintered at 1420 °C with different IOT addition, from 0 to 20 wt%, were investigated. The chemical and mineralogical analysis, and microscopic examination showed that IOT addition, up to 10 wt%, has little effect on formation of mineralogical phases. Furthermore, physico-mechanical tests showed the IOT addition within 10 wt% did not negatively affect the quality of the produced cement clinkers, on the contrary, could produce better quality clinkers than without IOT. These findings suggest that the high-magnesium and low-silicon IOT has a huge potential as cement raw materials instead of partial natural resources.

Experimental research on the rheological properties of tailings and its effect factors.

The rheological properties of tailings from gold, copper, and iron ore have been studied in this paper, using a self-developed large-scale type coaxial cylinder rheometer. The effect factors of the rheological properties of tailings, namely mineral types, particle size, plasma concentration, and the shear rate, and the influence they have on the viscosity and yield stress have also been studied. The test results showed that the viscosity of the tailings initially decreased with time and then became stable, while the yield stress initially increased with time and then tended to become stable. Three types of tailings all had a similar change trend with only small differences in value. The differences resulted from the varying mineral constituents of the tailings. The viscosity and the yield stress of the tailings increased as the concentration increased. As the shear rate decreased, the viscosity increased, but the yield stress also decreased. The change in magnitude of the yield stress increased as the concentration increased. It was also found that a larger particle size resulted in a higher viscosity and yield stress, the rise of which became more obvious at higher concentrations. The results were fitted using the exponential function of the Bingham model, and it was found that the coefficients of A1 and A2 changed significantly with the concentration, which indicated that A1 and A2 were largely influenced by other factors, and not only by the plasma concentration and particle diameter decisions. However, these functions of the Bingham model and the other coefficients of B1 and B2 were nearly constant. The three types of tailings also had a similar change trend for the fitted coefficients. There were some differences between the values associated with the type of tailings. For the same kind of tailings, the values of B1 and B2 were only slightly affected by other factors, while they were mainly influenced by the plasma concentration. The results of this research have provided the basic material for a stability study of a tailings dam and the analysis of movement law.

Mineralogical Features of Chalcopyrite and Sphalerite in Copper–Pyrite Ore Tailings in the Light of Prospects for the Purposeful Formation of Man-Made Deposits

The purposeful formation of man-made deposits is connected with the creation of such conditions under which a waste material acquires preset process properties while stored. This will enable future environmental clean processing of waste. Aiming to determine general mechanisms of formation of process properties in copper-pyrite ore tailings, the comprehensive analysis of mineralogical composition of tailings from three concentration plants processing ore from six large copper-pyrite deposits in the South Ural was performed. The crystal-chemical formulas of the basic ore minerals are studied and systematized. The morphological varieties of ore minerals are identified. It is found that even in case of deposits of the same genetic type, processing regimes and parameters of current mill tailings depend on the initial mineralogical features of waste based on which man-made deposits are formed. These features have influence on the mechanisms and stages of the secondary minerogenesis in the man-made deposits.

MODEL SPASIAL KERUSAKAN LAHAN DAN PENCEMARAN AIR AKIBAT KEGIATAN PERTAMBANGAN EMAS TANPA IZIN DI DAERAH ALIRAN SUNGAI RAYA, KALIMANTAN BARAT

<p>Illegal gold mining activities create mine pits, taillings, stressed vegetation and unvegetated land. The aims of this study were to identify and to develop spatial model of land degradation and water pollution caused by illegal gold mining activities in Raya watershed, West Kalimantan. The spatial land degradation model was developed by multiplication the score of mine age and type of mine tailings, while the scores for water pollution was based on the results of spatial distribution analysis of the water’s total dissolved solids (TDS) and Hg concentration levels in Lake Serantangan. Vegetations of the degraded area showed nutrient deficiency and toxicity symptoms. Based on the NDVI (normalized difference vegetation index), the degraded area generated a value range of 0.1-0.6. Mine land in the study area were classified as rather degraded (29.33%), degraded (28.70%), and severe degraded (41.97% of the total 4,551 ha area). While, 65.87% or 83 ha of the Lake Serantangan area was classified as severely polluted based on the water’s concentration of Hg and TDS. The accuracy of the spatial model developed was 88.30 and 82.57% for land degradation and water pollution, respectively.</p><p><br />Keywords: Illegal gold mining, land degradation, spatial model, water pollution</p>

Recycling and utilisation of industrial solid waste: an explorative study on gold deposit tailings of ductile shear zone type in China.

Tailings are solid waste arising from mineral processing. This type of waste can cause severe damage to the environment during stockpiling as a result of the leaching of something harmful into the ecosystem. Gold deposit of ductile shear zone type is an important type of gold deposit, and the recycling of its tailings has been challenging researchers for a long time. In this article, the characteristics of this type of tailings were systematically studied by using modern technical means. Considering the characteristics of the tailings, clay was selected to make up for the shortcomings of the tailings and improve their performance. Water and raw materials were mixed to produce green bodies, which are subsequently sintered into ceramic bodies at 980 °C~1020 °C (sintering temperature). The results showed that some new kinds of mineral phases, such as mullite, anorthite and orthoclase, appear in ceramic bodies. Furthermore, the ceramic bodies have a surface hardness of 5 to 6 (Mohs scale), and their water absorption and modulus of rupture can meet some technical requirements of ceramic materials described in ISO 13006-2012 and GB 5001-1985. These gold mine tailings can be made into ceramic tiles, domestic ceramic bodies, and other kinds of ceramic bodies for commercial and industrial purposes after further improvements.

Uranium Mobility in Waste Materials Generated by Uranium Mining and Hydrometallurgy: Implications for its In-Situ Immobilization

Six uranium tailings samples from the shallow depth of two large-scale uranium tailings ponds in South China, which were affected by pedogenesis, were analyzed to determine the occurrence modes of uranium. The results demonstrated that an average of nearly 80% of the uranium in the samples was mobile and potentially mobile, indicating that this type of uranium tailings could significantly threaten their ambient environment when their contents of uranium were relatively high. In this sense, the possibility of the in-situ immobilization of active uranium in the uranium tailings was discussed. The experimental data indicated that the active uranium could be immobilized through its reaction with phosphate, which was theoretically feasible and promising in curbing uranium pollution.

The Release Mechanism of Heavy Metals from Sulfide Tailings

The sulfide tailings is the main type of non-ferrous metals mine tailings, in which the sulfides could react with air, rain water and microorganism, etc. and then release some ions through a series of complex chemical interactions. The heavy metal ions leaching from tailings will cause serious pollution to the environment of mine region. The release mechanisms and effect factors of heavy metals ions from sulfide tailings are summarized in this paper.

Research on Application of Iron Tailings on Road Base

In order to make good use of waste iron tailings considering energy conservation and environment protection, a new research on the use of tailings in road base has been carried out in this study. A type of iron tailings stabilized with cement made of appropriate amount of cement was firstly selected as the semi-rigid base material. After the mix proportion design based on material characteristics, compaction tests, unconfined compression tests and economic analysis were conducted on the mixture. It shows that iron tailings stabilized with cement with a more than 15% cement content meets the test requirements well and can be applied on the base and subbase course of low-grade highway. Helping to save road materials and reduce project costs, the study has a promising application prospect.

Adsorptive removal of phosphate from aqueous solutions using lead–zinc tailings

This study explored the feasibility of utilizing lead-zinc tailings for phosphate removal in laboratory experiments. The adsorption isotherm, kinetics and pH effect were examined in batch experiments. The Freundlich and Langmuir isotherm models were used for data fitting. The adsorption kinetics can be best described by the simple Elovich equation. The phosphate adsorption tends to decrease with the increase of pH, from 0.37 mg P/g at pH 2.05 to 0.12 mg P/g at pH 7.01, and tends to increase from 0.12 mg P/g at pH 7.01 to 0.64 mg P/g at pH 12.52. The actual phosphate removal on the tailings could be a consequence of adsorption and precipitation reactions with Fe, Al and Ca. Due to their low cost, this type of tailings has the potential to be utilized for cost-effective removal of phosphate from wastewater.

Hydraulic conductivity and consolidation response of mixtures of mine waste rock and tailings

Hydraulic conductivity and consolidation behaviour are examined for an alternative mine waste disposal technique. One type of waste rock, one type of tailings, and mixtures of the same waste rock and tailings were tested in bench-scale and column studies. Specimens 150 mm in diameter were tested for hydraulic conductivity by falling-head method alternated with one-dimensional consolidation, specimens 300 mm in diameter were tested for one-dimensional consolidation response, and specimens 1 m in diameter were tested for self-weight consolidation behaviour in 6 m high columns. Deformation of mixtures under one-dimensional loading was similar to that of waste rock alone and much less than that of tailings alone. Hydraulic conductivity of mixtures was similar to that of tailings alone and independent of specimen diameter. Mixture behaviour was attributed to a homogeneous structure including waste rock in particle-to-particle contact and a continuous, saturated matrix of tailings. The results indicate that mixing waste rock and tailings can produce dense deposits with values of hydraulic conductivity that are orders of magnitude lower than those of waste rock alone, thereby limiting fluxes through the waste and the associated potential for acid rock drainage. Mixture deposits will also have less consolidation-related settlement than tailings, thus improving stability and aiding reclamation.

Mineralogical and geochemical alteration of Hitura sulphide mine tailings with emphasis on nickel mobility and retention

Weathering of Hitura (W Finland) nickel sulphide mine tailings and release of heavy metals into pore water was studied with mineralogical (optical and electron microscopy, X-ray diffraction) and geochemical methods (selective extractions). Tailings were composed largely of serpentine, micas and amphiboles with only minor carbonates and sulphides. Sulphides, especially pyrrhotite, have oxidized intensively in the shallow tailings in 10–15 years, but a majority of the tailings have remained unchanged. Oxidation has resulted in depletion of carbonates, slightly decreased pH, and heavy metal (Ni, Zn) release in pore water as well as in the precipitation of secondary Fe precipitates. Nevertheless, in the middle of the tailings area, where the oxidation front moves primarily downward, released heavy metals have been adsorbed and immobilized with these precipitates deeper in the oxidation zone. In contrast to what was seen in pore water pH, but in accordance with static tests of the previous studies, the neutralisation potential ratio (NPR) calculated based on the mineralogical composition and the total sulphur content suggested that tailings are ‘not potentially acid mine drainage (AMD) generating’. However, the calculated buffering capacity of the tailings resulted largely from the abundant serpentine because of the low carbonate content. Despite its slow weathering rate, serpentine may buffer the acidity to some extent through ion exchange processes in fine ground tailings. Nevertheless, in practice, acid production capacity of the tailings depends primarily on the balance between Ca–Mg carbonates and iron sulphides. NPR calculation based on carbonate and sulphur contents suggested, that the Hitura tailings are ‘likely AMD generating’. The study shows that sulphide oxidation can be significant in mobilisation of heavy metals even in apparently non-acid producing, low sulphide tailings. Therefore, prevention of oxygen diffusion into tailings is also essential in this type of sulphide tailings.