Potassium-containing feldspars provide a high potential for producing potash, a product with widespread use in agriculture. The present work assesses applying the anti-solvent crystallization method for the purification and recovery of high-purity muriate of potash (KCl) from feldspar leaching solutions. Initially, screening experiments were carried out on a synthetic leaching solution with the aim of analyzing the crystallization behavior of key components. Screening experiments were performed using five anti-solvents, namely methanol, ethanol, acetone, 2-propanol, and ethylene glycol. Acetone and 2-propanol were viable options for crystallization of potassium chloride. Then, the effects of anti-solvent ratio (O/A), time, and anti-solvent addition rate on potassium-chloride crystallization were further investigated using acetone and 2-propanol. A recovery of 83% of potassium was achieved when using acetone at the O/A of 5 with the addition rate of 10 mL/min, at room temperature with a hold time of 180 min. The optimum conditions for 2-propanol were determined to be similar, except for using a 5 mL/min addition rate for 79% recovery. The final muriate of potash products had a purity of over 99.9% using either of the anti-solvent. However, differences in morphology and crystal size of products were observed. Acetone-formed potash crystals were aggregates of cubic crystals with an average size of 3 microns, while 2-propanol-formed potash crystals were 20 microns in size as cubic particles with a hollow core. Despite having almost the same performance in potassium recovery, acetone was found to be a more feasible anti-solvent for potash recovery due to simpler downstream solvent recovery.

The global commitment to decarbonizing the transport sector has resulted in an unabated growth in the markets for electric vehicles and their batteries. Consequently, the demand for battery raw materials is continuously growing. As an illustration, to meet the net-zero emissions targets, the electric vehicle market demand for lithium, cobalt, nickel, and graphite will increase 26-times, 6-times, 12-times, and 9-times respectively between 2021 and 2050. There are diverse challenges in meeting this demand, requiring the world to embrace technological and knowledge advancements and new investments without provoking conflicts between competing goals. The uncertainties in a sustainable supply of battery minerals, environmental, social and governance complexities, and geopolitical tensions throughout the whole battery value chain have shaped the global and regional concerns over the success of transport decarbonization. Here, focusing on the entire value chain of electric vehicle batteries, the approaches adopted by regulatory agencies, governments, mining companies, vehicle and battery manufacturers, and all the other stakeholders are evaluated. Bringing together all these aspects, this literature review broadens the scope for providing multifaceted solutions necessary to optimize the goal of transport decarbonization while upholding sustainability criteria. Consolidating the previously fragmented information, a solid foundation for more in-depth research on existing difficulties encountered by governmental and industrial actors is created. The outcomes of this study may serve as a baseline to develop a framework for a climate smart and resource efficient supply of batteries considering the unique impacts of individual players.

It is well documented that the use of grinding aids (GAs) can reduce milling energy consumption. However, the impact of GAs on downstream processes must be addressed in view of complex processes such as froth flotation separation. This study investigates the effects of polyacrylic-based grinding aids (Zalta™ GR20-587: AAG) on the grinding performance and quartz flotation from magnetite. Various AAG dosages and conditions were examined. The grinding results showed lower energy consumption and a finer, more uniform product size with roughened surfaces for AAG compared to grinding without the grinding aid. Flotation tests of single pure minerals showed that AAG enhanced quartz collection with minimal effect on magnetite. Mixed mineral flotation showed that by using AAG, Fe recovery of 92.1 % and 64.5 % Fe grade could be achieved with a lower collector dosage of 100 g/t compared to 200 g/t in the absence of AAG. Zeta potentials and stability measurements showed that AAG shifts the potential, thus improving the stability and dispersion of the suspension. Adsorption tests illustrated that AAG adsorbed on both quartz and magnetite, the former having a higher capacity. FTIR indicated the physisorption interaction between AAG and the minerals. Therefore, the presence of AAG not only improved grinding efficiency but could potentially decrease the amount of collector required to achieve comparable metallurgical performance.

Grinding is the most energy-intensive step in mineral beneficiation processes. The use of grinding aids (GAs) could be an innovative solution to reduce the high energy consumption associated with size reduction. Surprisingly, little is known about the effects of GAs on downstream mineral beneficiation processes, such as flotation separation. The use of ecofriendly GAs such as polysaccharide-based materials would help multiply the reduction of environmental issues in mineral processing plants. As a practical approach, this work explored the effects of a novel polysaccharide-based grinding aid (PGA) on magnetite's grinding and its reverse flotation. Batch grinding tests indicated that PGA improved grinding performance by reducing energy consumption, narrowing particle size distribution of products, and increasing their surface area compared to grinding without PGA. Flotation tests on pure samples illustrated that PGA has beneficial effects on magnetite depression (with negligible effect on quartz floatability) through reverse flotation separation. Flotation of the artificial mixture ground sample in the presence of PGA confirmed the benefits, giving a maximum Fe recovery and grade of 84.4 and 62.5%, respectively. In the absence of starch (depressant), PGA resulted in a separation efficiency of 56.1% compared to 43.7% without PGA. The PGA adsorption mechanism was mainly via physical interaction based on UV–vis spectra, zeta potential tests, Fourier transform infrared spectroscopy (FT-IR), and stability analyses. In general, the feasibility of using PGA, a natural green polymer, was beneficial for both grinding and reverse flotation separation performance.

It is well documented that chemical additives (grinding aid “GA”) during grinding can increase mill throughput, reduce water and energy consumption, narrow the particle size distribution of products, and improve material flowability. These advantages have been linked to their effects on the rheology, although there is a gap in understanding GA effectiveness mechanism on the flow properties. The present study aims to fill this gap using different GAs (Zalta™ GR20-587, Zalta™ VM1122, and sodium hydroxide) through batch grinding experiments of magnetite ore and addressing the mechanisms of their effects on the rheology by an FT4 Powder Rheometer as a unique system. Experimental results showed that GA improved grinding efficiency (energy consumption and product fineness), which were well-correlated with basic flow energy, specific energy, aerated basic flow energy, and aerated energy. Moreover, the rheometry measurement showed strong linear correlations between basic flow energy, specific energy, and the resulting work index when GAs was considered for grinding, which confirmed the effect of GA on ground particles’ flowability. Zalta™ VM1122, a polysaccharide-based grinding aid, showed the best performance with 38.8% reduction of basic flow energy, 20.4% reduction of specific energy, 24.6% reduction of aerated basic flow energy, and 38.3% reduction of aerated energy. It also showed the strongest correlation between the grinding parameters and flow parameters (r > 0.93). The present investigation shows a strong indication that the predominant mechanism of GAs is based on the alteration of rheological properties and identify Zalta™ VM1122 as the best GA.

Mineral liberation as the main purpose of comminution in ore beneficiation is not applied in the design of comminution machines or even often neglected in designing comminution circuits. In addition, other factors critical for comminution efficiency such as fracture energy, and particle fragmentation are rarely considered. The current study investigates the combined effects of particle textural properties and process operational conditions on the fragmentation of bed particle. In particular, the influence of ore texture and loading displacement rate (as the material and machine properties) on particle specific fracture energy, breakage mode, liberation, and fragmentation was studied. The results indicate that ore textures with coarsest grain sizes and lower quantities of cleavage minerals have the least amount of fracture energy. In terms of fragmentation, a lower displacement rates results in higher quantities of the fragmented particles compared to the higher displacement rate. Among studied ore textures, two types of hematite ore textures which had the coarsest grain sizes had lower liberation in finer size fractions. Overall, the outcomes show that the displacement rate and ore texture can affect the specific fracture energy, particle fragmentation, mineral liberation, and breakage mode at different degrees.

Understanding and optimizing the comminution process in terms of mineral liberation, fragmentation, and fracture energy are aligned with sustainable approaches and overall international goals of green solutions. This study investigates the combined effect of material properties (ore textural features) and process factors (displacement rate) on mineral liberation, fracture energy, and fragmentation. For achieving this aim, multivariate data analysis tools are used to examine the fragmentation by compression of multiple layers of iron oxide minerals in a particle bed. The results indicate that ore textural features distinctively influence particle fragmentation, mineral liberation, and fracture energy and the ore textural effects are more pronounced compared to displacement rate.

There is a lack of skilled operators for mineral processing plants in the mining sector, which might be related to the challenge of creating trainings that addresses the operator’s daily work problems. In recent years, the use of simulator-based trainings as a tool to build competence has grown in many different fields. With the help of technologies like virtual reality, these tools have been demonstrated to increase awareness and the capability of workers when compared to traditional learning methods. In this paper, a review is presented on the development and application of such technologies in simulation-based training for the training of operators of the minerals industry in the last 20 years. Proposed next steps and new technologies with the potential of improving these applications are also discussed.

Trainings play a vital role in the transference of knowledge between skilled and novice operators in the mineral industry. Evaluation is an important part of those trainings, but many trainings rely solely on the trainees’ feedback. This paper presents how technology enhancement can help produce more effective training evaluations to the mineral industry. It describes a case study involving a froth flotation simulator-based training, including details of the simulation, user interface, and the training program. The training was delivered to sixteen mining operators and evaluated by both the traditional method (trainee's feedback) and with the simulation's learning evaluation. The feedback evaluation showed a high level of satisfaction with the learning results, while the learning evaluation showed a very different training outcome, putting established evaluation methods such as Kirckpatrick's “Four levels” into question. Correlations between the learning results and the operators’ personal information such as process work, and academic experience are also presented.

Current advances and developments in automated mineralogy have made it a crucial key technology in the field of process mineralogy, allowing better understanding and connection between mineralogy and the beneficiation process. The latest developments in X‑ray micro-computed tomography (µCT) have shown a great potential to let it become the next-generation automated mineralogy technique. µCT’s main benefit lies in its capability to allow 3D monitoring of the internal structure of the ore sample at resolutions down to a few hundred nanometers, thus excluding the common stereological error in conventional 2D analysis. Driven by the technological and computational progress, µCT is constantly developing as an analysis tool and successively it will become an essential technique in the field of process mineralogy. This study aims to assess the potential application of µCT systems, for 3D ore characterization through relevant case studies. The opportunities and platforms that µCT 3D ore characterization provides for process design and simulation in mineral processing are presented.

Aktuelle Fortschritte und Entwicklungen in der automatisierten Mineralogie haben diese zu einer wesentlichen Schlüsseltechnologie im Bereich der Prozessmineralogie gemacht, die ein besseres Verständnis und eine bessere Verknüpfung zwischen Mineralogie und dem Aufbereitungsprozess ermöglicht. Neueste Entwicklungen in der Mikro-Röntgen-Computertomographie (µCT) haben gezeigt, dass sie ein großes Potenzial haben, die zukünftige automatisierte Mineralogietechnik zu werden. Der Hauptvorteil der µCT liegt in ihrer Fähigkeit, eine 3D-Verfolgung der inneren Struktur einer Erzprobe mit Auflösungen bis hinunter zu einigen hundert Nanometern zu ermöglichen, wodurch der übliche stereologische Fehler bei der konventionellen 2D-Analyse ausgeschlossen wird. Angetrieben durch den technologischen und rechnentechnischen Fortschritt entwickelt sich µCT als Analysewerkzeug ständig weiter und wird sukzessive zu einer unverzichtbaren Technik im Bereich der Prozessmineralogie. Diese Studie zielt darauf ab, die potenzielle Anwendung des µCT-Systems für die 3D-Erzcharakterisierung durch relevante Fallstudien zu beurteilen. Die Möglichkeiten und Plattformen, die die µCT 3D-Erzcharakterisierung für Prozessdesign und Simulation in der Mineralaufbereitung bietet, werden vorgestellt.