Modelling the transient drainage of liquid in foams

Froth flotation is the largest tonnage separation process worldwide and is used for paper deinking, water purification and, particularly, mineral separation. One of the key aspects of the performance of flotation cells is the behaviour of the liquid within the froth, as it is crucial to the purity of the product and a major influence on the overall recovery. Nonlinearities in models for liquid motion in the froth make them complex to solve and existing numerical solutions have been in two dimensions at most. In order to predict the performance of industrial flotation cell designs, a three-dimensional solution for these equations is desirable. Moreover, the understanding of the process would be enhanced if a transient model were used to predict the dynamics of foam drainage. In this work, the equations for the liquid drainage have been rearranged in order to make them analogous to a compressible version of the Navier-Stokes equations, coupled to an equation of state. A model for predicting the movement of the flowing foam has also been developed, which is able to solve for the foam velocity in two and three dimensions. This has allowed the transient behaviour of liquid in flotation foams to be modelled using Fluidity, a general purpose finite element method code that allows simulations to be carried out on unstructured adaptive meshes. This is an important feature for improving the computational cost of modelling these systems, as there are boundary layers present in the process, whose size is independent of the scale of the flotation system being modelled. These models have allowed, for the first time, to carry out numerical investigations of drainage for arbitrary flotation tank geometries in up to three dimensions, and have been verified against analytical solutions and compared to laboratory scale experiments with satisfactory agreement

Soft Computing Application in Mining, Mineral Processing and Metallurgy with an Approach to Using It in Mineral Waste Disposal

Abstract In the past two decades, the mining sector has increasingly embraced simulation and modelling techniques for decision-making processes. This adoption has facilitated enhanced process control and optimisation, enabling access to valuable data such as precise granulometry measurements, improved recovery rates, and the ability to forecast outcomes. Soft computing techniques, such as artificial neural networks and fuzzy algorithms, have emerged as viable alternatives to traditional statistical approaches, where the complex and non-linear nature of the mineral processing stages requires careful selection. This research examines the up-to-date use of soft computing techniques within the mining sector, with a specific emphasis on comminution, flotation, and pyrometallurgical and hydrometallurgical processes, and the selection of soft computing techniques and strategies for identifying key variables. From this, a soft computing approach is presented to enhance the monitoring and prediction accuracy for mineral waste disposal, specifically focusing on tailings and spent heap leaching spoils database treatment. However, the accessibility and quality of data are crucial for the long-term application of soft computing technology in the mining industry. Further research is needed to explore the full potential of soft computing techniques and to address specific challenges in mining and mineral processing.Abstract In the past two decades, the mining sector has increasingly embraced simulation and modelling techniques for decision-making processes. This adoption has facilitated enhanced process control and optimisation, enabling access to valuable data such as precise granulometry measurements, improved recovery rates, and the ability to forecast outcomes. Soft computing techniques, such as artificial neural networks and fuzzy algorithms, have emerged as viable alternatives to traditional statistical approaches, where the complex and non-linear nature of the mineral processing stages requires careful selection. This research examines the up-to-date use of soft computing techniques within the mining sector, with a specific emphasis on comminution, flotation, and pyrometallurgical and hydrometallurgical processes, and the selection of soft computing techniques and strategies for identifying key variables. From this, a soft computing approach is presented to enhance the monitoring and prediction accuracy for mineral waste disposal, specifically focusing on tailings and spent heap leaching spoils database treatment. However, the accessibility and quality of data are crucial for the long-term application of soft computing technology in the mining industry. Further research is needed to explore the full potential of soft computing techniques and to address specific challenges in mining and mineral processing

Topical scientific researches into resource-saving technologies of mineral mining and processing

Table of contents Preface . 5 Malanchuk Z.R., Soroka V.S., Lahodniuk O.A., Marchuk M.M. Physical-mechanical and technological features of amber extraction in the Rivne-Volyn region of Ukraine . 6 Moshynskyi, V.S., Korniyenko V.Ya., Khrystyuk A.O., Solvar L.M. Research of energy effective parameters of the process of hydro mechanical extraction of amber from sandy deposits . 24 Mohamed Tafsir Diallo, Mamadou Oury Fatoumata Diallo Tidal Park – Modeling and Control Strategy . 38 Savina N.B., Malanchuk L.O., Ignatiuk I.Z., Moshchych S.Z. Institutional basis and trends of management of the use of the subsoil in Ukraine . 51 Dedelyanova Kr.Y. Column flotation machine – innovative aeration, vibra-tory – acoustic and technological researches . 60 Makarenko V.D., Manhura A.M., Lartseva I.I., Manhura S.I. Magnetic field on asphalt, resin, paraffin and salt deposits 79 Krzysztof Tomiczek The problem of beds stability in the conditions of undermining higher deposited beds in the context of selected analytical solutions . 95 Safonyk A.P., Koziar M.M., Martyniuk P.M., Fylypchuk V.L. Management of pollution - purification system for mining plants . 117 Marinela Panayotova, Vladko Panayotov Recent developments in the flotation of sulfide ores of base metals - bioflotation . 130 Remez N., Dychko A., Bronytskyi V., Kraychuk S. Simulation of shock waves from explosion of mixture explosive charges . 149 Melodi M.M. Akande V.O. Analysis of productivity and technical efficiency in granite aggregate production in selected quarries in south-western, Nigeria . 166 Doroshenko Ya.V., Karpash O.M., Rybitskyi I.V. Investigation of dispersed contaminates influence on the hydraulic energy consumption of elements of gas pipeline systems with complex geometry . 182 Skipochka S.I., Krukovskyi O.P., Krukovska V.V., Palamarchuk T.A. Features of methane emission in coal mines at high speed longwall face advance 208 Daouda Keita, Valery Pozdnyakov Statistical analysis of experimental data on the indices of operation of the loading units of the bauxite compa-ny of Guinea (CBG) . 226 Yevhenii Malanchuk, Sergiy Stets, Ruslan Zhomyruk, Andriy Stets Modeling of the process of mining of zeolite-smectite tuffs by hydro-well method . 244 Samusia V. I., Kyrychenko Y. О., Cheberiachko I. M., Trofymova, O. P. Development of experimental methods to study heterogenic flows in the context of hydraulic hoisting design . 260 Makarenko V.D., Kharchenko M.O., Manhura A.M., Petrash O.V. Magnetic treatment of production fluid with high content of asphalt-resin-paraffin deposits . 268 Kovshun N.E., Ignatiuk I.Z., Moshchych S.Z. Malanchuk L.O. Innovative model of development of fuel and energy complex of Ukraine 279 Bondarenko А.O., Ostapchuk O.V. Design and implementation of a jet pump dredge . 296 Sotskov V.O., Dereviahina N.I. Research of dependencies of stope stress-strain state change under various conditions of partial stowing of developed space . 305 Sakhno S., Liulchenko Y., Chyrva T., Pischikova O. Determination of bear-ing capacity and calculation of the gain of the damaged span of a railway overpass by the finite element method . 326 Melodi М.М., Ojulari M.K. Oluwafemi V.I. Economic and environmental impacts of artisanal gold mining on near-by community of Sauka-Kahuta, Nigeria . 340 Kruchkov A.I., Besarabets Y.J., Yevtieieva L.I. Energy saving modes of excavators type power shovel . 353 Hryhorash M.V., Kuzminskyi V.P., Ovchinnikova O.V., Kukhar V.Yu. Energy saving through quality of technical water: new types of mechanical screen filters for various links of water treatment . 369 Didenko M. The modeling of the interaction of rock mass and compliant lining while it is expanded . 394 Makarenko V.D., Liashenko A.V. Complex approach to research and selection of hydrocarbon solvents for asphaltene-resin-paraffin-hydrate deposits control . 408 Mykhailovska O.V., Zotsenko M.L. Investigation of the oscillations amplitudes bases and foundations of the forming machine . 417 Inkin O.V., Puhach A.M., Dereviahina N.I. Physical-chemical and technological parameters of improving profitability of underground coal burning . 42

CHARACTERIZATION AND DESULPHURIZATION OF REACTIVE MINE TAILINGS

A site-specific study is carried out to assess the suitability of froth flotation for desulphurization of reactive mine tailings with an Outokumpu flotation unit, type OK0.05 at the Musselwhite Gold Mine, Northern Ontario, Canada, to prevent acid mine drainage (AMD). Based on the data presented in this study, the maximum recovery of total sulphur was achieved when the operational parameters were set to the froth depth of 5 cm, air flow rate 125 L/min, impeller speed 1300 rpm and pulp density 35%. Another objective of this research is to develop a robust, rapid and easy digestion procedure for analysis of total sulphur in mine tailings using Inductive Coupled Plasma. It is found that the aqua regia (1 ml HNO3 + 3 ml HC1) digestion of 0.1 gm of samples for only 40 minutes of heating at 95°C produced fast, safe and accurate analytical results with a recovery of 97% for the selected reference materials

Utilization of digital twin in model-based control of flotation cells

Optimization of flotation plants has become an important field of research as the demand for minerals is growing rapidly. The goal of the optimization is to reach the maximum recovery while keeping the grade of the product within limits. The trend in optimization controllers is moving towards model-based control as the long delays and time constants make it hard for other type of control laws to operate while getting the response models for the controllers requires long tests at the plant. In this thesis, a flotation model is created with HSC tool by Outotec and it was fitted according to real plant data. The model is then tested as a tool for producing the response models for the grade-recovery optimizer by making steps to froth speed models which are operated by controlling the air flowrates of the cells. Results showed that the model produced dynamics that were close to those of the real plant but estimation of the plant gain proved to be difficult with the available plant data. The gain is mostly affected by the relations between mineral kinetics, the change in air flowrate during the step and the cell by cell recovery. The results show that it is possible to use HSC to produce a priori model, but the gain of the response would have to be fitted with the traditional plant tests. Getting the model to produce correct gain would require more analysis points with more analyzed elements which would make kinetics fitting possible.Vaahdotusrikastuksen optimoinnin merkitys on kasvanut, koska mineraalien tarve on kasvanut voimakkaasti. Optimoinnin tavoitteena on saavuttaa mahdollisimman korkea saanti pitäen mineraalipitoisuus sille asetettujen rajojen sisällä. Optimoinnin trendi on suuntautumassa mallipohjaisiin säätöihin sillä pitkät viiveet sekä aikavakiot tekevät prosessista vaikeasti säädettävän muille säätöratkaisuille, mutta mallien aikaansaaminen kuitenkin vaatii pitkiä testejä laitoksella. Tässä tutkielmassa tehtiin vaahdotusrikastuksen malli HSC-sovelluksella ja se sovitettiin saatavilla olevaan laitosdataan. Mallin soveltuvuutta pitoisuussaanti optimoijan tarvitsemien vastemallien tuottamiseen testattiin tekemällä askelmaisia muutoksia vaahdon nopeusmalliin, joka sääti rikastuskennojen ilmansyöttöä. Tuloksista selvisi, että malli tuotti laitosdataa vastaavat dynamiikat, mutta vahvistus oli vaikea saada oikeaksi. Vasteen vahvistukseen vaikuttaa voimakkaasti mineraalien kinetiikkojen suhde, vaadittava ilmavirtauksen muutos askeleen aikana sekä kennokohtaiset saannit. Tuloksien pohjalta HSC:llä on mahdollista tuottaa a priori mallit vasteille, jotka kuitenkin vaatisivat vahvistuksien sovituksen laitoksella. Vahvistuksen oikeaksi saaminen vaatisi lisää analyysipisteitä sekä enemmän analysoitavia elementtejä, jolloin kineettisten vakioiden sovitus olisi mahdollista

INVESTIGATION OF THE STABILITY OF LIQUID AND AIR FILMS BY SYNCHRONIZED TRI-WAVELENGTH REFLECTION INTERFEROMETRY MICROSCOPE

Liquid films are widely involved in many processes, such as froth flotation, oil extraction, foam/bubble stabilization, etc. In the meantime, air films are commonly seen in diverse fields like dust control, ink print, coating industry, and so on. Stabilities of these liquid/air films are of great importance to improve the processes. As more and more researchers are paying increasing attention to liquid/air films, tremendous efforts have been made to explore the properties of the films. On the one hand, some theoretical models have also been well developed in recent decades. State-of-the-art technologies, such as AFM, SFA, and RICM, have also been employed to visualize the films in either a direct or indirect manner. However, due to the limitations of the techniques, it is still challenging to fully uncover the mechanisms of the film stabilities. A new and powerful methodology to characterize the film properties has been a top priority. In this work, a novel technique, namely Synchronized Tri-wavelength Reflection Interferometry Microscope (STRIM), was developed in our lab. It allows the accurate measurement of a separation distance within a range of few nanometers to micrometers. Based on the previous RICM, STRIM employs two additional light sources and achieves the determination of the absolute distance. The accuracy of the film thickness measurements was found to be within 1 nm over a range of 0-200 nm and within 3 nm over the range of 200–1000 nm. By recording the thinning process of films, STRIM is able to reconstruct the spatiotemporal profiles, which contain massive information. First, the conditions under which the films are stable or unstable are the urges to figure out for industrial applications. Besides, the films\u27 stabilities are closely related to the interfacial properties, and thus they can be alternative indicators of some essential properties, such as hydrophobicity. Additionally, the interactions and surface forces across the films between involved surfaces can be calculated by the dynamic film thinning kinetics, unraveling the underlying mechanisms for the processes of interest. Furthermore, other approaches, including AFM, contact angle measurement, and flotation, are also referred to in this work and confirm the drawn conclusions. The STRIM can investigate both the liquid and air films with the flexibility of controlling the involved objects like the surfaces with adjustable hydrophobicity and media with designed properties. This newly-developed equipment has the potential to be extensively used within the colloid and interfacial science and engineering areas

Froth flotation characterization and processing plant design for the platiniferous and auriferous marine sediments of Southwestern Alaska

Thesis (M.S.) University of Alaska Fairbanks, 2007The purpose of this study was to characterize, and investigate the beneficiation of, the platiniferous and auriferous marine sediments of Southwestern Alaska, located near Platinum, Alaska. The majority of placer gold particles are contained in the 50 x 150 mesh size fraction, while the platinum is finer, residing in the 100 x 200 mesh size fraction. Liberated placer gold and placer platinum group metals (PGM) particles are visible to the naked eye and readily observed under a binocular microscope. Preliminary, qualitative microprobe analysis of PGM grains from the flotation concentrate showed grains of nearly pure iridium, isoferroplatinum and Pt-Rh-Ir-Fe-S-As mineralogy. Froth flotation showed that placer gold responded very well to all the collectors used, with gold recoveries of 82.7-99.8%. Flotation of platinum responded well to only potassium amyl xanthate, with a recovery of 80.4%. Results of low intensity magnetic separation showed that virtually all the liberated gold and platinum reported to the non magnetic product. A flowsheet, with estimated capital and operating costs, was developed to process 1500 tph of marine placer feed. Annualized costs per ton to process marine sediments were estimated to be $2.40 to$3.72 depending upon plant availability, 90% to 50%, respectively.1. Introduction and research objectives -- 2. Description of Goodnews Bay platinum deposit -- 3. Literature review -- 4. Sample collection and preparation -- 5. Description of metallurgical test work -- 6. Results and discussion -- 7. Metallurgical flowsheet design and cost estimation -- 8. Summary and conclusions -- References

Development and intensification of a foam flotation system in harvesting microalgae for biofuel

PhD ThesisDue to their photosynthetic efficiency, microalgae tend to have high lipid content and growth rates, hence their importance to the biofuel sector. However, the viability of microalgae-derived biofuel is hindered by high capital and/or operating costs required for cultivation, harvesting, and drying. Harvesting the microalgae cells represents a substantial process cost, accounting for an estimated 30% of the total cost of production particularly because of the low concentration of microalgal biomass relative to water in the algae culture. Foam flotation can be utilised as an energy-efficient harvesting and enriching technique for microalgae biomass with the potential to significantly reduce the production cost of algal fuel. In this thesis, foam flotation was used for the first time in a continuous mode to harvest freshwater and marine microalgae species in an attempt to overcome the trade-off between recovery efficiency and enrichment in batch and semi-batch foam flotation. The influences of cell surface characteristics on flotation performance were investigated by quantifying hydrophobicity, zeta potential, and contact angle. Fractional factorial and response surface designs of experiment were used to determine the best operating conditions to achieve an effective combination of a high recovery efficiency (for greater biomass removal from the growth medium) and concentration factor (to lower downstream dewatering and drying costs). Tubular setups of different smooth-successive contraction and expansion ratios (foam riser) were used for the first time to enhance foam drainage. A recovery efficiency of 91% was obtained for Chlorella vulgaris with a concentration factor of 722. Foam flotation demonstrated a much lower power consumption (0.052 kWh m-3 of algae culture) in comparison to other flotation techniques including dissolved air flotation and electro-flotation. The algal biomass harvested by foam flotation was processed directly using hydrothermal liquefaction (HTL) without extra stages for dewatering and drying or intermediate storage. Thus, it can offer precise investigations on the process feasibility and it also represents a more realistic scenario for the application of HTL. The fate of surfactant in harvested microalgae and its effects on the HTL product yield and distribution were also investigated. HTL of C. vulgaris recovered by foam flotation demonstrated that the surfactant had additional benefits on HTL product yield, distribution, and composition. Overall, foam flotation is an effective, rapid, low cost, media (and arguably species) independent, scalable harvesting system which is able to operate continuously. Foam flotation also delivers algal biomass having additional advantages for biofuel productionHigher Committee for Education Development in Iraq (HCED)