To be Updated with new approved abstracts

Among the many initiatives being developed to recover and reuse mineral waste at Vale mining sites, the new business solution presented here uses silica-rich tailings as a substitute for primary silica to produce engineering stone products like kitchens countertop, bathroom vanities and floor tiles in a booming, multi-billion dollar industry.
Engineering stone is an alternative to natural stone like granite. It is manufactured from approximately 93% primary silica, 7% resin, colour pigments and selected aesthetic additives, with the recipes varying depending on desired colour and aesthetic properties.
Using primary (typically white) silica allows engineering stone manufactures to produce products with a wide colour range, so when used, residual (darker) iron ore in tailings can somewhat decrease colour control. Through innovative technological advances combined with a skilled and highly motivated workforce, Vale has been able to systematically improve separation efficiency of its concentration/beneficiation processes (primarily aimed at maximizing the recovery of iron ore). Fortuitous laws governing mass balances have ensured that increased recovery of iron ore in one stream has meant an associated increase in silica content of the other stream (tailings), in some strategic process streams as high as 90-96% SiO2. Such a systematic increase in the silica content (becoming whiter) has meant an increase in the colour control Vale silica-rich tailings can deliver the industry.
Since 2014 Vale has been working closely with leaders in the engineering stone manufacturing industry to develop recipes. This collaboration is delivering engineering stone that not only meet EN 14617 industry standards for resistance to stain, strength and impact but also have colour ranges able to satisfy market needs.

Russia is one of the world leaders in coal production. In-place coal reserves of Russia account for one third of total world coal reserves and one fifth of world explored reserves. At that, some 4-5 t of overburden rock is stripped in surface mining and up to 0.2-0.3 t of mine rocks are produced in underground mining per of 1 t of mined coal. In addition, in the process of coal preparation in 2016 more than 30 mln t of solid waste were generated and on coal-fired thermal power plants 25 mln t of ash and slag waste (ASW) were produced.
Solid wastes of coal mining, preparation and burning are discharged to dumps which occupy large areas of valuable ploughlands, worsen landscape of the territory, are the sources of environmental pollution, and their storage involves relatively high capital and operational costs.
A sustainable solution of the problem of efficient use of industrial waste depends on several factors, namely, material composition of waste, its aggregative state, quantity, technological characteristics, etc.
The problem of non-waste technologies has ecological, resource saving, technological and technical, economical and organizational aspects.
The areas of efficient use, technical requirements, technical solutions and innovative trends in the processing of technogenic coal deposits have been determined based on the analysis of basic regularities of development of their physical and chemical properties, aggregative state, quantity and natural heterogeneity.

The subject of this dissertation research is the analysis of the sensitivity of the geo-mechanical stability of slopes of the surface coal mines of the main influential factors. Its main purpose is to define the interaction between the geological environment and the engineering activity. This definition should derive from defined properties and conditions of the geological environment, on one side, and the impact of the engineering activity, on the other.
It is regarded that without proper methodological approach, successful resolving of any geotechnical problem is not possible.
In general, various methods are used for slope stability analysis. They can roughly be divided into two groups, such as:
- Border balance methods and
- Numeric methods.
In general, the slope stability analysis consists of the following components:
- Safety Factor Fs ;
- Slope � Geometrical properties;
- Physical-mechanical properties of tested soil materials;
- Groundwater.
Following significant results occurred from the work on this doctoral dissertation:
- Analyzis and sensitivity evaluation of the safety factor in the change of the values of certain geo-mechanical parameters;
- Analysis of the reliability of the geo-mechanical parameters that affect the geo-mechanical stability;
- Critical review of the selection of methods for geo-mechanical stability analysis;

The capabilities of �XRF to analyze large rock samples without any significant sample preparation has opened up new areas of research and application in the field of applied mineralogy. In this case study, we present the results of the analysis of a range of specimens from Au-epithermal deposits in Chile and New Zealand using the Bruker M4 TornadoAMICS �XRF located at Universidad Catolica del Norte, Antofagasta, Chile. The results demonstrate the ability to detect and identify the presence of Au- or Ag- bearing mineralogy whilst maintaining spatial and textural relationship information. The specimens analyzed have a gold grade of between 20 and 100 ppm with known gold and silver mineralogy dominated by native gold, electrum and acanthite with the presence of lessor concentrations of other Ag-sulfosalts. Specimens range in size from 10 to 20 cm in maximum dimension. For each specimen, a rapid (30 - 60 minutes) coarse scan at 100 to 200 �m was used to identify areas of interest which were then subsequently analysed at a higher resolution (5 to 20 �m) for longer count times per pixel (20 to 100 ms). The results were clearly able to distinguish gold and/or silver rich areas within the various specimens and highlighted the diverse range of spatial and textural conditions under which such mineralogy is formed within the vein. For example, the Au- and Ag- bearing mineralogy was commonly associated with the presence of sulphide (chalcopyrite, sphalerite, and galena) rich zones, however, in contrast there are examples where the such mineralogy occurs in areas with no sulphide mineralisation. Continued detailed analyses will provide mineralogical and elemental information which can be interpreted within a real spatial context and thus providing additional information for understanding geological processes of formation and modelling, as well as metallurgical classifications for mineral processing.

Automated Mineralogy, and specifically the SEM-EDS-AM solutions available, have played vital roles in the development and application of modern process mineralogy. Since the initial development and introduction into the market, these technologies have contributed to optimizing mineral processing plants around the world. Despite their success and undisputed value, until recently the development of these solutions, in terms of the solutions methodology and analytical capabilities, has been limited. This talk aims to introduce and outline the history of these solutions with the view to providing an insight into the current state of play and new capabilities of the solutions within automated mineralogy. This will include modern trends and case studies that show these solutions are moving towards mine sites that utilize these newly ruggedized and deployable automated mineralogy solutions to adopt an operational mineralogy approach. This will act as the background, and as an introduction, to what future developments we can expect to see in automated mineralogy, and how these developments will be critical in providing reliable and routine on-site mineralogical analysis that will be required as mines of the future looks to adopt a Mining 4.0 capability. In addition, technological developments such as the use of machine learning and widening the analytical capability with 3D data and wider analytical instrumentation. These topics will be used to outline the future roadmap of AM and how these solutions will become strategically more valuable for 4.0 mining operations.

Flotation is a conventional and most common technique for minerals beneficiation. However, its efficiency drops dramatically when floated particles size falls below 30 µm. With the depletion of rich deposits and the rising need to develop poor finely disseminated ores, which requires grinding down to particles sizes well below 30 µm, the challenge of fine particles flotation comes to the forefront. Solving this problem by increasing flotation time and bubbling rate inevitably involves increased investments and production costs, and the decrease in the concentrate quality and valuable component recovery rate. In certain cases, these considerations become critical for taking the decision on the deposit viability.
The theoretical and experimental findings show that the most effective approach to fine particles flotation challenge involves the application of fine bubbles, which are smaller than 5x(particles size). However, practically it is not feasible to generate a large amount of fine particles below 100 µm in size in conventional pneumo-mechanical flotation cells. Hence, extended research has started to design an apparatus for producing fine bubbles outside the flotation cells and introduce bubbles into a cell as air-in-water dispersion. It has been proven both theoretically and experimentally that even small volumes of fine bubbles contribute to significant increase of flotation efficiency. The method, which uses the combination of conventional coarse bubbles and fine bubbles acting actually as flotation carriers, is termed «combined microflotation».
The purpose of the present study is to establish the effectiveness of microbubbles application for beneficiation of finely dispersed (80% below 33 µm) magnetite concentrate (iron content 64.5%) by reverse flotation in pneumo-mechanical cells at actual production facilities of Poltavsky Concentrator (Gorishni Plavni, Ukraine). The industrial scale generator “SEBBA-5” (delivered by Turboflotservice Company) was used as a microbubble source. This generator produces bubbles smaller than 50 µm. The results have shown that the relative increase of the flotation rate (when the iron content in the concentrate reaches 68%) is practically in direct ratio to the volume dose of fine bubbles per feed unit weight. In particular, at the microbubble dosage of 0.005 m3/t flotation rate constant has increased by 8.7% and at the dosage 0.015 m3/t – by 25%.

Comminution circuits are historically one of the most difficult parts of a mineral processing plant to design with confidence. There is controversy in the industry as to how best to approach this subject, with many solutions requiring a level of training and expertise beyond the ability of a non-specialist engineer. This has led to a culture of experts who opine on the subject with little or no direct benefit to the design process and the plant operator. In order to change this, mineral industry owners and senior managers need to understand the fundamental challenges that a comminution circuit poses to the design process, to the operators who use the equipment, and to the owners who invest in a project. This presentation is intended to summarize these challenges in a manner which is clear and unbiased, in a format which is applicable and which offers creative and practical solutions to the mining and mineral engineering community. A proper understanding of SAG mill hardness measurement and workable operating options, reveals the rich benefits of SAG/AG milling technology which are available for every new or retrofit project.

The floatability of non-magnetic (Non-Mag) & magnetic (Mag) pyrrhotite (Po) in Cu-Ni sulfide ores (chalcopyrite-pentlandite) is an important area of research that is receiving more attention as concentrators seek to remove more Po from their final Ni concentrate. Based on both lab-scale and industrial data available in the current literature, it appears both Po polymorphs exhibit different flotation responses mainly due to their surface chemical differences, which is the result of their different crystal structures. This preliminary study summarizes the bench-scale Denver cell flotation results (coarse and fines: +38 and -38um, respectively) of three Cu-Ni sulfide ore bodies containing 30%, 50%, and 95% Non-Mag Po (balance being Mag Po). The main goals were to assess whether Po type had an impact on total Po recovery and pyrrhotite-pentlandite (Po-Pn) selectivity both in the coarse and fines fractions, +38 and -38um, respectively. For the three ores (all size fractions combined), the results indicate that Non-mag Po is much more floatable than Mag Po, increasing Non-Mag Po feed content increased total Po recovery, consequently, Pn selectivity was poorer against Non-mag Po than Mag Po. Comparing coarse (+38um) and fines (-38um), Po-Pn selectivity curves showed much poorer selectivity in the fines over coarse sizes (attributed to poor floatability of fine Pn). In the fines, the preliminary results showed that Non-mag Po was more floatable and that both polymorphs followed the trend of decreasing selectivity with increasing Mag Po feed content, this warrants further investigation with cyclosized fractions. For the coarse fraction, Pn selectivity against Non-mag Po was poorer than Mag Po. The findings from this study demonstrate that there are indeed quantifiable differences in the flotation responses of the polymorphs, which are primarily the result of their unique crystal structures and therefore different surface chemistries.

Over the last years the intensive development of copper hydrometallurgy has been observed in Kazakhstan. It is based on the use of heap leaching and extraction technology for production of high purity cathode copper at high economic efficiency. In VNIItsvetmet the researches on the application of extraction technology for the processing of copper-bearing Kazakhstani raw materials have been carried out since 1997. More than 15 copper ore deposits of oxide and mixed type were tested.
In addition to the study of the material composition of ores and the set of heap leaching researches, the specialized tests on selection of the most suitable organic extractant are carried out. The results of the research are used to draw up a feasibility study, develop process procedures and implement the projects. VNIItsvetmet also provides scientific and technical support for exploitation of the developed technologies.
There are three plants for the processing of oxide copper ores based on the use of heap leaching and extraction technology, operating on the basis of our developments at the Kounrad deposit (with a production of 13,000 cathode copper per annum), Ayak-Kodzhan deposit (3,000 cathode copper per annum) and Aktogay deposit (15,000 cathode copper per annum). Three more plants with a total production of about 15 thousand cathode copper per annum are being prepared for launch in 2017-2018 at the Zhezkazgan, Ay and Almaly deposits.

Water is one of the important parameters in flotation, and represents 80–85% of the volume of mineral pulp processed in flotation circuits. Our recent studies revealed that the ground sulphide minerals in contact with water generated H2O2, but its effect on the oxidation of pulp components, and hence in deteriorating the concentrate grade and recovery in flotation, has not been explored yet. In this study, effect of two types of water on formation of H2O2, an oxidizing agent stronger than oxygen, was investigated. It was shown that process water generated more H2O2 than tab water. This trend highlights the importance of understanding the mechanism of between process water and sulfide minerals on flotation.

Recently, several studies have been carried out on the reinforcement of cementitious building materials by plant fibers, which represent an important sustainable and eco-friendly material. Hemp fibers have long been valued for their high strength and long fiber length, and used extensively in the fabrication of ropes, sails and textiles. In this paper, the influence of embedded length on the bond properties between raw untreated hemp fiber and cement mortar was investigated. Tensile tests were carried out to examine the mechanical properties of hemp fibers. Based on the results of pull-out test the key parameters of interfacial bonding including maximum pull-out load, shear strength and toughness were evaluated. It was found that the pull-out resistance for experimental material system was controlled by strong frictional effects. Rough surface of untreated hemp fiber and possible accumulation of damage fibers within the interface seem to provide a mechanical barrier at the interface, leading to a significant increase in interfacial friction during the pull-out process. Based on the findings of present study, cement composites with enhanced toughness can be produced using hemp fibers as reinforcement.

The modern economy is highly dependent on specific raw materials, and it is envisaged that this dependency will increase in the near future. Most of them are scarce in the European Union (EU) and of poor purity, being mixed with complex and low-grade aggregates which need to be processed by means of a separation process consuming high quantities of energy and water, and even in some cases, this makes its exploitation unfeasible due to production costs. Being EU dependent on some of these materials, as identified by the European Innovation Partnership (EIP) initiative, our society is demanding more efficient extracting processes to contribute to major European independency on these Critical Raw Materials (CRMs). Tungsten and Tantalum ores are two recognized CRMs: In a market currently dominated by China and Russia production (among others), in Europe Tungsten (limited) production is mostly concentrated in UK, Spain and Portugal. On the other side, Tantalum is a key element on electronics with clear EU external production dependency, as it is naturally really scarce in Europe (only 1% of world production is concentrated in EU). Knowing this situation, OptimOre Project as a first EU project on raw materials has started a comprehensive research and development of modeling and control technologies in order to study the secure sustainable supply of raw materials (Tungsten and Tantalum) to the European economy whilst increasing benefits for society as a whole. The approach to do this was based on, using advanced sensing and industrial control, artificial intelligence techniques, aiming to increase yield in 7-12% on the current best production processes and increasing energy saving on a 5% compared to the best available techniques. This work consists of 8 partners in 4 different countries and 7 advisory board from industry.
In this paper will present industrial impact development approach in OptimOre project introducing a general techno-economic impact of this project. The number of the successful non-disclosure agreement (NDA) with different relevant companies in Europe have been discussed.

The international mineral processing community has over the years embraced various developments in technology to do with the characterization of ores and processed mineral products, particularly with respect to mineralogy and ore texture analysis, such that there is now a bewildering number of them. Some techniques produce data and information that is the same, others are very unique, and there are a few which are proving to be game-changing. This paper will attempt to summarize the main techniques that are available to the scientist and engineer alike, then discuss what they are used for, and finally how they compare to each other. Techniques currently utilized in allied earth resources industries, such as petroleum engineering, but not generally known to mining and processing engineers, will also be mentioned, along with lessons learned. These techniques, no matter which ones used, are here to stay, and a sound understanding of them is absolutely essential if one is to maximize the information gained from an ore in the pursuit of sustainable mineral processing. The paper will be of interest to experienced users of mineral-based technologies, as well as those who want to learn more about them, and is a celebration of 40 years of development.

A wide range of inorganic concentrates with different properties makes it difficult to directly apply the theory of filtration and requires the use of modeling methods.
In this regard, the development of models of filtering processes is actual.
The filtration process with the formation of compressible sediments is particularly important. This process involves the use of experimental data, as well as the development of a methodology for calculation of filtration system.
The purpose of this work is the development of mathematical models of filtration with the formation of compressible sediments using a filtration system of concentrates (e.g., liquid sulfur).
To achieve this goal, it is necessary to solve the following problems:
1. determination of the dependence of the porosity of the concentrates' sediment on the compressive stress;
2. determination of the relationship between the porosity of the sediment and its specific resistance;
3. determination of the dependence of the specific resistance of the sediment on the impurity concentration;
4. determination of the influence of filter pore sizes on the cleaning efficiency of suspended particles by filtration method;
5. development of a mathematical model of the filtration process through the membrane layer;
6. development of a mathematical model for filtration of concentrates with the formation of a compressible sediment;
7. improvement of the liquid sulfur filtration system.

This paper intends to find some alternatives to recover gold associated with oxide and sulphide ore by mixing its main component (copper sulfide) with oxide ores using for this purpose the metallurgical flotation process. The development of this research has evaluated samples of this type of ore content of 15%, 10% and 5% of oxidized ore. This way is to evaluate which of these allow us to obtain a higher gold recovery without damaging the copper grade and recovery thereof in the concentrate. To determine the mineralogical species, with which is associated the gold, and the degree of release of such species has made a study of optical microscopy of polished sections: Head, concentrate and tailings. At the end of the study better metallurgical performance 15g / t of a mixture of (formatexanthate + thionocarbamate) is obtained, achieving a 13% increase in the recovery of gold.

Chemical assays have long been the benchmark technique to value prospects and mines from early stage exploration all the way through to metallurgical accounting. However, while the mines are looking at extracting metals, it is the minerals that dictate where the metals are located. This can also be extended to deleterious elements and problematic minerals for the processing circuit. Minerals, not elements, control processing behavior, therefore early and appropriate characterization in the mining lifecycle will add significant value to an operation.
The potential for process mineralogy to play a major role in process improvement is well recognized but has historically been limited in its practical application due to issues including expense, long turn-around time and data complexity. Recent technological advances have started to change this, making such information accessible and usable by minerals engineers in the field or on site. Automated Mineralogy (AM) is one of the primary tools used in such work, and ZEISS MinSCAN is the first truly ruggedized system that can be deployed on site. Based on technology used by the military in field operations, the instrument is designed to operate in environments not typically associated with such tools and can provide data such as bulk mineralogy, element assay and deportment, liberation, and association rapidly and easily.
Mine sites can now produce data, almost real time, to monitor the plant performance. There is also a growing demand to implement this solution at an earlier prefeasibility stage, to feed into geometallurigcal modeling to reduce risk in earlier prediction and decision. This data offers a common language and dataset that can be used by all stakeholders in the mine development from exploration geologists through to metallurgists.
This paper outlines the technological innovations of the AM solutions, the ruggedized developments and how they can be successfully employed to mine site operations.

The modern best practice of process mineralogy has developed over the last three decades into an effective business machine by integrating the disciplines of sampling, mineralogy and mineral processing to design and arrange a mineral processing flowsheet more optimally. Together with the advances made in mineralogical instrument design, leading to programmable automated platforms such as Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN), or Mineral Liberation Analyser (MLA), supporting methodology in sampling based on the models of Pierre Gy, 1979, such as Statistical Benchmark Surveying, and in flotation testing such as High-Confidence Flotation Testing (HCFT), have greatly enhanced the ability of this integrated system to deliver sound, quantitative process implications for practical use to improve the performance of the mineral processing flowsheet. The selection and training of these teams has also proved to be a very influential factor in this outcome. It is the cross-training and interaction between these disciplines that delivers a synergy to the overall flowsheet development effort. Several case studies will be discussed, as well as the existing modern structure of the best practice.

The Nechalacho deposit, located in the Northwest Territories, Canada, is a heavy rare earth element (REE) deposit. Of the various REE-bearing minerals in the deposit, zircon is of significant importance, due to its elevated heavy rare earth element (HREE) content. Previous studies investigating the use of gravity and magnetic separation in the processing of this ore showed that coarse particles following grinding were enriched in zircon, suggesting the potential for selective comminution. The current work investigates the possibility to selectively comminute gangue minerals and concentrate REE-bearing zircon into coarser size fractions. The ore was ground wet in a laboratory ball mill for various lengths of time (0, 10, 20, 30, and 40 min). The grind size which resulted in the greatest grinding characteristics (upgrading, recovery, liberation) for zircon was then processed by dense medium separation (DMS) to determine further upgrading could be achieved by gravity separation. ICP-MS was used to determine the distribution of zirconium and REEs, and QEMSCAN, to identify mineral phases, mineral liberation and the distribution of minerals for both the comminution study and the DMS test work.

Trepca mine in Stantrg (Kosovo) is a lead, zinc and silver mine.This mine is using fly-ash as a back-fill material since 2010. This material is transported by special trucks from the lignite-fired power stations in central part of Kosova � Obiliq. As the discharged fly ash is a serious environmental problem, it was very important to use this material for back fill in the underground mines, although the considerable amount of ash is available to the cement producers in the region. Using fly ash in the underground mines as a hydraulic filling is very important to increase the safety of mining facilities and setting conditions for the working efficiency of the mining method. Although prior to the use of fly ash in the mines, there were a series of laboratory examinations and reviews on the physical model, after a certain period of time we face with the problem of the layer in the tubes for the vertical transport of the fly-ash. This layer becomes so thick that the tubes have been blocked and it was necessary to replace them. Replacing the tubes was an additional problem, both for the production and for the maintenance. In this paper is presented practical solution how to avoid creation of the layer in the tubes for the vertical transportation of fly-ash in the underground lead and zinc mines in Kosovo.