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By Silvia França, Hudson Couto, Renata Barbosa

"The flotation process, largely used for mineral concentration processes, which is based on air bubble adhesion to the dispersed solid phase, is also being used for wastewater treatment purposes. Dissolved air flotation (DAF) is based on the separation of the solid-liquid phases with the aid of small air bubbles (10-100 µm), with high values of interfacial contact area, improving the process efficiency. In the process, the air bubbles and particles or flocs form aggregates, which rise to the surface of the flotation cell to be collected. The advantage of producing small bubbles is directly related to the fact that smaller bubbles result in greater bubble-particle interaction. Wastewater produced in alumina refinery - from the red mud filtration step - has a red colored aspect due to the presence of very fine particles of red mud and also dissolved matter that still remain in the filtrate. This wastewater might be treated, aiming to reuse the water in the refinery or discharge it properly in the environment. The aim of this study was to evaluate the DAF process efficiency for the treatment of red mud wastewater in order to decrease suspended particles and dissolved solids contents, in addition to mitigate the high causticity of this wastewater. The process efficiency was evaluated by comparing turbidity removal and total solids concentration in the treated wastewater to the feed. The influence of important variables of the DAF process as type and concentration of coagulant and flocculant were evaluated. It was possible to obtain good turbidity removal efficiencies (up to 90%) using low concentrations of coagulant (50 mg/L) and flocculant (0.5 -1.0 mg/L). In addition, for most of the experiments, the specification for effluent diposal, according to the Brazilian environmental regulation 430 (Conama, 2011): pH range 5 to 9 and turbidity < 40 NTU, was attained. These results emphasize the possibility of using the DAF as an alternative technique to settling and filtration process, that are traditionally used, for treating wastewater from the alumina industry, allowing the reuse of water in the plant or adequate discharge with less environmental impact."

Jan 1, 2014

By Tuan V. Nguyen, Kosta Simic, Louis Mittoni, Murray Rudman, Jean D. Swift, John B. Farrow, Phillip D. Fawell

"Research projects towards developing a sound understanding of the factors controlling the performance of gravity thickeners have been conducted by the AJ Parker Cooperative Research Centre for Hydrometallurgy since 1988 through AMIRA International. The current phase of this work, the three year P266D .Improving Thickener Technology. project, has 27 sponsors comprising mineral processing companies, reagent suppliers and thickener manufacturers.These projects have resulted in the development of a range of tools and techniques to address flocculation, thickening and associated dewatering issues. A number of Computational Fluid Dynamics (CFD) models have been developed to predict likely full-scale thickener performance under various process conditions, based upon a knowledge of thickener design, plant flows and assessment of the flocculation behaviour of the feed slurry. At the same time, various laboratory and plant studies have been used to quantify important thickener processes, and to provide validation of the CFD models. These numerical and experimental capabilities have been applied to various thickener issues across a broad range of mineral processing operations, leading to significant process improvements and substantial financial benefits.This paper presents an overview of the work conducted during these projects, focussing on the research tools, the nature of the information that has been gained and the implications for thickener performance."

Jan 1, 2003

By E. V. Bratygin, S. P. Elnikova

"In the article carrying out technique of experiments for estimation of power efficiency of process of crushing in cone crushers «in a layer». The conformity of the granulometric characteristics of the crushed products obtained as a result of the tests, the theoretical equations for the size characteristics, and the choice of the optimal equation for the prediction of the granulometric characteristics of the final products obtained by crushing ""in a layer"". Optimization of granulometric composition of power of crushers working ""in a layer"" is carried out with the purpose of reduction of the electric power consumption at reception of a product of required quality. As a result of the experiments, dependencies are obtained, the relevance and applicability of the crushing process ""in the layer"" for obtaining crushed stone of improved quality is proved. INTRODUCTION A number of equations have been proposed for calculating the breakage energy. These include equations by Kirpichev and Kick, Rittinger and Bond (Bogdanov, Olevsky, 1982). Another equation for calculating the specific breakage work in breakage by impact and in stratum was proposed by Devyatkin (Boiko, 2003). In these equations, the breakage energy is proportional to the particle size raised to some power. In the equation proposed by Devyatkin, the ore piece thickness or the feed average diameter is used. The relationship between energy and breakage can be expressed as an equation (Lynch, 1981; Tikhonov, no. 3, 2008) where k is a coefficient characterizing the energy parameter depending on the strength of the feed, l is size in microns. The Rittinger formula is obtained for n = 2, the Kirpichev-Kick formula for n = 1, the Bond formula for n = 1.5. For n = 3 or higher, the equation describes fine and ultrafine grinding. R. Hookey proposed a formula (Lynch, 1981, Tikhonov, no. 3, 2008), where the size exponent n is substituted by a size function In all of the above equations, a single value of the feed and product size is used; for example, in the Bond equation, size is defined as the particle size of the 20% oversize (P80 and F80). However, a single size value can represent multiple distributions, making that the Bond method inappropriate for determining the size (Lynch, 1981). Describing an equation for estimating the grinding energy will allow to design the electric drive and ore preparation circuit for the given breakage method."

Jan 1, 2018

By William Conger, Greg Schick

Grinding media consumption is a major cost variable in industrial mineral comminution circuits. Specifically, industrial SAG media consumption results from a combination of surface abrasion wear, media breakage, surface spalling and rejection size from the mill. Three main consumption rates; weight of media consumed per time, per kWh and per weight of ore ground are defined and compared. Recent industrial data has provided an opportunity to relate consumption in terms of weight of media consumed to weight of ore ground (g/tonne) and weight of media consumed per kWh of energy consumed (g/kWh) with SAG specific grinding energy consumed (kWh/tonne). Using relationships developed from this data it is possible to project SAG media consumption in future mineral comminution circuits.

Jan 1, 2014

By V. Sheikhzadeh, M. Saghaeian, R. Hejazi, A. Abazarpoor

The research aimed to compare the chemical analysis (K, Na, Cl) of Iranian concentrate plants, which are the main source of materials corrosion in the pelletizing plants. Cl alongside alkaline elements (especially K) may cause corrosion and plug in the grate plates and other involved equipment. Therefore, it is tried in the processing plants to remove impurities from the concentrate to prevent potential problems in pelletizing and iron/steel making processes. Part of these impurities are existed in the nature of ores and others are sourced in the processing water. Various samples from the largest Iranian concentrate plants including Chadormalu, Gol-e-Gohar, Jalal-Abad and Sechahun were prepared to investigate the possibility of alkaline problems for each samples. The amount of Cl, K and Na of Chadormalu sample was obviously low and therefore no alkaline problem is expected. The Cl content of Gol-e-Gohar sample was high (980 ppm) while amount of K was less (0.008 Wt. %). Due to low content of K, most of Cl will release as Cl2 or HCl and so problems caused by KCl plugging would not be a problem. The amount of Cl in Sechahun case was nearly same as Jalal-Abad (400-600 ppm), higher than Chadormalu and less than Gol-e-Gohar samples. However, the K content was higher than all samples (0.04 Wt. %). Therefore, the amount of evaporated K would be 2-4 times more than other samples. Since the amount of Cl and K is simultaneously higher than usual iron ores, therefore alkaline problems may be a serious prevention factor for the continuous operation of this plant. In order to solve this problem some counter-measures is suggested and discussed including cleaning system, partial dust enriched with KCl removal and variation in the materials type of involved equipment.

Jan 1, 2018

By P. Condori

In spite of the importance of the slurry transport and discharge in autogenous and semiautogen-ous (AG/SAG) mills, it is evident that a more comprehensive and useful model is still required. Semi-empirical models used up to now have many limitations and cannot be used beyond the ranges in which they were developed. The breakage of particles as they are transported along a mill com-plicates the experimental analysis and the modelling of the transport process within the mill. The interaction of the grate discharge and the pulp lifters, with the added issue of backflow from the pulp chamber into the mill, makes the discharge modelling process difficult. In order to overcome these difficulties, a mechanistic approach has been applied. The general transport and discharge model was subdivided into four independent models: Flow through the charge, flow through the grate, flow in the pulp lifter, and flow-back. This paper gives an overall description of the modelling approach and discusses in particular the modelling of transport of fluids through the charge. In order to evaluate and calibrate the model, experimental work was carried out. To evaluate the gradient pressure under different conditions of charge packing and flow rate, a specialised experimental rig with a highly sensitive pressure gauge was used. Preliminary results identify the differences of the charge and grate on the restriction of flow. The existence of a dynamic voidage in our particular system was more evident and as a result, a semi-empirical correlation for the voidage was developed. In general, results show that the me-chanistic model derived from Ergun?s equation for flow through a packed bed can be satisfactorily adapted.

Jan 1, 2014

By O. A. Bascur

"In recent years, metal producing companies have increased their investment in automation and technological innovation, embracing new opportunities to enable transformational change. Internet of Things (IoT) is one of many transformational initiatives, which can fundamentally revolutionize how industrial complexes operate. Whatever the issue, the answer is in the abundant and growing quantity of real time data and events collected in the grinding and flotation circuits in a mineral processing plant. Based on earlier work, today a grade recovery model permits identifying the best operating conditions in real time. We will review the strategy for increasing the value of the abundance instrumentation in current plants. An optimal Gaudin size distribution model provides augmented information from traditional sensors to find the optimal grind cut to reduce metal losses in the flotation circuits. The large amount of sensors in a flotation circuits permits to estimate the recovery and to find the optimal froth depth and aeration using an air holdup flotation model. The paper will describe the strategy of classifying data for on line generation of insights to using operational intelligence tools. We will discuss the implementation Recovery/Grind strategy with industrial examples in non-ferrous mineral processing and iron beneficiation.INTRODUCTIONThe declining supplies of high grade ores and increasing consumption of mineral and metal products have demanded higher operational efficiencies with minimum capital investments. The objective of copper flotation objectives are based on maximizing the dollars return on the concentrate produced. The economic efficiency is maximized by manipulating the circuit along the grade/recovery curve relationship. To achieve such objective improved stabilization of the grinding and flotation circuits are required (Oosthuizen, Craig, and Jamsa-Jounela, 2017)."

Jan 1, 2018

By V. Hema

Granular materials are widely used in process industries, such as chemical, pharmaceutical, cement, food, detergents, and fertilizers. Mixing, blending, calcining, reduction, heating, and granulation of these materials are frequently carried out in rotating cylinders. In all of these processes, the mixing and segregation of these granular materials is important as this controls the secondary phenomena in the rotating kiln such as heat transfer to the material. A significant amount of work is available in the literature but to date these efforts have not been able to capture the important parameters affecting the mixing and segregation in rotating kilns. In addition, the range of parameter values studied so far is rather limited. Simulations of granular materials are based on either discrete elements or continuum models. The discrete element methods (DEM) combine semi-empirical models for the inter particle interactions with the equations of motion from classical mechanics to simulate the explicit paths of all granules in a rotary kiln, thus yielding realistic predictions of the mixing process. This approach is very demanding computationally, which strongly limits the number of granules and the number of revolutions in a simulation. Continuum models dispense with the discrete particles and can therefore be scaled up more easily. But the constitutive relations that serve as the foundation for continuum modeling are difficult to come by, and often only applicable to specific systems and conditions. Here we have chosen DEM simulation for investigating the mixing and segregation behavior of granular materials in a rotating cylinder. This work is directed towards demonstrating the capability of the prediction of the mixing and segregation behavior of granular materials in a horizontal rotating cylinder through discrete element simulation. Further the effect of particle size and rotational velocity on the mixing and segregation behavior is investigated. The simulation results are quantified in terms of mixing index, mixing rate, segregation index and percolation index. Keywords: DEM simulation, granular mixing

Sep 1, 2012

By Valentin V. Shatalov, Irina V. Pastukhova, Alexander V. Kurkov

"We have developed a technology to improve the quality of low-grade concentrates containing minerals of tantalum, niobium and tin on the basis of given conception by the way of improving selectivity and using certain reagents composition. The basic collector presents a traditional or complex-forming collector used together with organic diphilic reagents – the secondary reagents regarding the basic flotation regiment, capable of forming associates with the main collector on the surface of the mineral, thus altering the interaction energy. In the given process the main collector is the fraction of hydroxamic acids C7-C9, the reagent of the secondary action – sulphosuccinamate, which added in moderate concentrations range provides for a synergistic effect.We have determined the parameters of the process stability and necessary modifying reagents for a selective recovery of tantalum, niobium and tin minerals from refractory products. Variants have been studied where the main collector and the secondary action reagent were substituted with some more efficient flotation reagents. A possibility of a more flexible reagent compounding for the process has been shown. The flotation process is highly stable regards the saline composition of the liquid phase in the pulp. It can operate under conditions of the complete water recycling with the total salt content up to 12 kg/m3, iron up to 1.2 kg/m3.The given results consider the efficiency testing of the suggested technology for the gravitation products, which were obtained from ores of various genesis and contain large quantity of the most refractory minerals, such as topaz (80%), gamet (55%), tourmaline (30%). High selectivity of the process has been registered with the metal recovery about 92-98%, which appears to be similar to hydrometallurgical operations under certain conditions."

Jan 1, 2003

By J. Yianatos

The cleaning circuit operation and its effect on the plant metallurgical performance, was characterized at Los Pelambres concentrator, Chile. Experimental data from columns, scavenger and regrinding stages was evaluated. Each stage was characterized by size fractions, and the interaction between stages (columns, scavenger, regrinding) as well as the effect that circulating loads had. The approach for describing the flotation equipment operation (cells and columns) considered the collection and froth zones separately. This methodology allows for the identification of the impact that particle size distribution has on the actual collection and froth transport processes, independently. In this way the effect of regrinding on flotation recovery and grade can be related to the corresponding operating variables, e.g. pulp flowrate, air flowrate, pulp level and pulp density, among others. The effect of gangue entrainment was considered using an empirical dimensionless correlation. The interaction between the circulating load and the overall performance of cleaning circuit was evaluated. The circulating load was defined as the ratio between the solid flowrate of scavenger concentrate over rougher concentrate. It was found that the overall cleaning flotation circuit (column-scavenger) can operate at a relatively high and constant recovery for a wide range of mineral treatment. This is possible when the scavenger has the capacity for compensating the decrease in column recovery at larger circulating loads. Under the condition of high overall cleaning recovery, the rougher stage closely represents the plant recovery. However, at large mineral treatment conditions, the design characteristics (e.g. concentrate transport channel capacity and transfer boxes) as well as instrumentation, control facilities and operation, became bottle-necked. A simulator was developed using empirical models for each stage (column, scavenger and regrinding) in order to evaluate proper operational strategies for cleaning flotation circuits Keywords: flotation, cleaning, regrinding, Vertimill, simulation.

Sep 1, 2012

By J. Y. Xu

A mutant of Phanerochaete chrysosporium, which is capable of degrading lignin, was bred by ul-traviolet ray irradiation and this mutant strain shows high capability of degrading of lignite. The degradation ratio of original Yima lignite and nitric acid treated Yima lignite by this mutant are 37.6% and 51.62%respectively, whereas those by the original strain are 31.84% and 32.55% respectively. XRD and FTIR analyses of the lignite converted product show that its polymerization degree and average molecular weight are both greatly reduced. The content of the functional groups is also been altered.

Jan 1, 2014

By Carin Laubscher, Francis W. Petersen, Jaap P. Smit

Waste streams, such as acid mine drainage, are often characterised by low pH values and high concentrations of heavy metals, dissolved solids, calcium and sulphates. Although lime remediation effectively removes most of the heavy metals as hydroxides, it is less effective at lowering levels of sulphates. Various methods of removing sulphates from effluents exist, such as precipitation with lime, precipitation with barium salts, co-precipitation with calcium carbonate, reverse osmosis, and ion exchange. Mintek developed a chemical precipitation (SAVMIN) process to treat acid mine drainage, which entails the addition of lime to precipitate the metal hydroxides, and the subsequent formation (precipitation) of calcium sulphoaluminate or ettringite. The key to the viability of the new technology lies in the correct use, regeneration and recycling of Al(OH)3 used to precipitate the ettringite. The water produced by this process is suitable for disposal to watercourses or for agricultural, domestic or industrial consumption. No brines are produced as the salts are converted to solid hydroxides, gypsum and calcium carbonate. The technology has been tested on several different waters in pilot plant campaigns. Results obtained indicate that potable water can be produced (containing less than 200 mg/L sulphate and no heavy metals) as long as the monavalent ions (Na+, Cl-, etc.) are within limits.

Jan 1, 2003

By Ata Akcil, Z. B. Karshigina, Ye. G. Bochevskaya, E. A. Sargelova, Z. S. Abisheva

Phosphorus slag is one of the most large-tonnage of yellow phosphorus production waste, which for decades stored in the slag disposal, by polluting the environment and creating environmental problems in the regions. Phosphorus slags from the processing of Karatau phosphorites are a very promising source of raw materials not only for silicon compounds but also rare earth metals (REM). Among the REM, yttrium, neodymium, europium and lutetium predominate, which are relevant to high-tech industries. The report presents technological scheme of complex processing of slags of phosphoric production with obtaining of REM concentrate and precipitated silicon dioxide ("white soot"). The regime parameters of the main operations of the technology are determined: I stage- leaching of slag with nitric acid solution; extraction of the REM-containing solution with tributyl phosphate and stripping of the REM with water; settling of solution of salts of oxalic acid, calcining the precipitate to obtain a concentrate S REM oxides and II stage of leaching silicon cake to obtain "white soot". Recovery of S REM from slags of phosphoric production on various redistribution has made, %: leaching – 95.0; extraction - 90.2; extraction on the average ~ 93.2; the production of a concentrate of REM oxide is 93.9. A concentrate containing 17.3 % of REM oxides was obtained. According to X-ray analysis it contains the following phases: calcium oxide, portlandite2, gadolinium oxide and yttrium, gadolinium oxide, gadolinium oxide and cerium, neodymium oxide, neodymium oxide and cerium. Thus, the concentrate can serve as a raw material for the production of individual rare-earth metals like gadolinium, cerium, yttrium and neodymium. After performing the II stage of leaching siliceous cake with nitric acid the samples of "white soot" were obtained. Its chemical composition corresponds to the state standard and has a specific surface area equal to 180 - 200 m2/g. The technology has been tested in a large-scale laboratory scale and will solve the problem of complex processing of phosphorus raw materials and import substitution in Kazakhstan. The end-to-end recovery of S REM oxides and silicon into concentrate and product from their initial content in slags is ~ 75.0 and 98.0 %, respectively.

Jan 1, 2018

By Mario Gerards

Maturing populations create an increase in the demand for the type of non-ferrous metals, which are used in the manufacturing of electronic products. The depletion of existing high-grade deposits, make it necessary to boost the efficiency of beneficiation processes and most importantly the yield (recovery rate of the value commodities). Increasing demand now makes it worthwhile to tap into resources, which were previously considered waste, for example secondary deposits such as tailing ponds and electronic waste. In order to achieve increased yields, increasingly finer, or even ultra-fine fractions have to be treated. In most cases, mineral characteristics such as size and density call for non-mechanical, high-capacity technologies to be used. There are various technologies that allow for the separation of fines and ultra-fines. This paper outlines the dynamics and efficiency of pneumatic flotation with emphasis on its application to the recovery of non-ferrous metals, from electronic waste. The conventional agitator flotation technology of an electronic waste processing plant was not able to recover ultra-fine non-ferrous metals satisfactorily, due to losses within the tailings. Because of its adaptability and its inherent suitability for non-ferrous metals, pneumatic flotation has been incorporated to the existing process achieving excellent results. The merit of the process lies in the state of the art technology, which does not utilize compressed air and any rotating parts, which results in a reduction in wear and energy requirement, both features of this innovative technology. In addition, the use of pneumatic flotation resulted in a significant reduction in residence time, when compared to mechanical flotation. Pneumatic technology is able to influence air bubble size in a flotation cell, by changing the speed and pressure of the slurry stream. Higher slurry velocities lead to the formation of smaller air bubbles, which is required for the successful flotation of ultra-fine particles. Conversely, decreasing the slurry velocity leads to bigger air bubbles. The optimum bubble size can be created according to different feed characteristics. This is important in case of feed fluctuations.

Sep 1, 2012

By X. Y. Zeng

Most Chinese titanium bearing minerals are the composition of magnetite vanadium and ilmenite. All of such mineral processing plants use low intensity magnetic separators to recover magnetite and vanadium goes with magnetite. In the past years most of the plant tails containing about 10% TiO2 were abandoned. Now many of these plants use SLon magnetic separators to recover ilmenite in the roughing stage, which can throw away most of the gangs and slimes with very low cost. The new development of applications of SLon magnetic separators in Chinese ilmenite processing industry is introduced in the paper.

Jan 1, 2014

By M. Kargar Razi

According to the unique properties and many applications of nano gold powder, it was prepared from an acid leaching tail solution. The low value residual gold ions were existed in acid leaching tail solution in Mouteh gold mine in Iran with fellow heavy metals as pollutants (FeP2+P, Cu P2+P, and ZnP2+P). Preparation of nano gold particles is achieved by two steps. First, by addition of ammonia as separation step and second using suitable reagents for precipitation/extraction step. Conditions control includes pH, residence time, temperature, agitation, and molar ratio of reducing agents to reagents. The optimum results show that nano gold powder was prepared by temperature of 250 °C, urea to gold molar ratio of 3:1, and reduction time of 20 min. Also, heat treatment improves dispersion of nano sized gold particles. The properties of gold nano powders were evaluated by SEM, A.A, and UV- Vis spectroscopy methods. The size of prepared particles were about 80nm to 90nm.

Jan 1, 2014

By Juan Pablo Segovia, Alonso Pereira, Fernando Concha, Daniel Sbarbaro, Samuel Vergara

A robust theory of sedimentation-consolidation evolved and was accepted by researchers worldwide in the last two decades of the 20th century. This theory provides a reliable method of thickener design, simulation and control. However, a process model, simple or sophisticated, empirical or phenomenological, is useful only if it is possible to determine, in an objective way, its experimental parameters. Although it is important for a mineral processing plant to perform periodical laboratory test to determine thickening parameters, and in this way adjust the operation, not always these tests represent the behavior of the material in the process. It is important to be able to determine these parameters directly in the thickeners. Research workers at the University of Concepción developed new instrumentation, algorithms and software for the determination of thickening parameters. In this paper, two new instruments for the on-line determination of the settling velocity and the compressibility of the sediment are presented and results of tests in a major mineral processing plant in Chile are described.

Jan 1, 2014

By N. Naudé

The theory on particles displacement subjected to upwards and settling movements in water, using a water pulse, is described in literature, but very little experimental data is available to verify these theoretical ideas. The aim of this research work was to visualize the displacement of solid particles in a mixture of water and solid particles created with the aid of water pulses in the Mineral Density Separator. From the literature it is known that lighter particles are subjected to higher levels of displacement than heavier particles, and when the particles then settled down, layers of material are formed ac-cording to the densities of the material. By removing the individual material layers, the materials can then be separated according to their densities. During this study the individual material layers were investigated regarding the density and size distribution in that specific density layer. It is important for this project to have a statistical prediction of the ?real? flow of the particles with different density and size distribution, inside the Mineral Density Separator. The information gathered during this study will be used to show the correlation between a two dimensional model of the particle flow and that of the real three dimensional flow inside the Mineral Density Separator.

Jan 1, 2014

By I. N. Gridasov, T. V. Ignatova, E. V. Shelepov

"Mikhailovskoye Deposit is comprised of oxidized ferruginous quartzites among other minerals with the former widely spread across the ore field and mined along with unoxidized ferruginous quartzites. PJSC Mikhailovsky GOK strategic development is aimed at iron ore product output expansion. The most critical item of the strategic development road map is process design for separation and concentration of hematite contained in oxidized ferruginous quartzites mined as the by-product in the open pit. Laboratory and semi-industrial tests run to design cost-effective, reliable and environmentally friendly process for Mikhailovskoye deposit oxide quartzites processing included the following processes: - pilot tests of reverse anionic flotation which produced concentrate with Fe60.1-62.9% total iron content and 66-69%Fe recovery rate; - combined magnetic separation and flotation (Marubeni Company, 1982) including slime removal, reverse anionic and cationic flotation and high gradient magnetic separation resulting in 48.9% yield, Fe55-57.5%, up to Fe60.5% hematite concentration ( Fe64.1% being the best result achieved),76.2% recovery. - magnetic separation and flotation, including separation in low gradient (1400 Oe) and high gradient (up to 17000-18000 Oe) magnetic field. The results of these pilots tests were the following: 57-59%Fe concentrate, 70%Fe recovery (Mekhanobrchermet, MGOK, 1982-1988): - magnetic roasting in pilot plant of TSGOK (Krivoy Rog) which produced 61.1%Fe concentrate with 81.5% recovery. Major disadvantage of the method is high generation of dust equal to 20% of the initial feed. Based on third-party studies flotation of oxidized ferruginous quartzites process embracing best processing methods was designed by Metalloinvest Management Company LLC and PJSC Mikhailovsky GOK engineers. This paper discusses analysis of studies aimed at intensification of separation processes with application of mechanical slurry agitation (MSA), addition of alkali (NaOH) and elutriation of initial feed. The paper also provides a design solution to implement a lab-scale MSA plant. It includes feasibility evaluation of MSA inclusion in flotation of oxidized ferruginous quartzites process to enable higher yield and hematite recovery in resultant concentrate. Outcomes of the discussed work have significant value for prospective engineering of OFQ concentration process."

Jan 1, 2018

By Xiaodong Jia, Williams. Richard A.

This paper describes the recent developments, arising from research at Leeds, in the computer modelling of packing of complex shaped particles and prediction of physical properties of the structures represented by the packing. The computer model DigiPac, is capable of packing particles of any shapes and sizes in a container of arbitrary geometry. The ability to predict packing structure of real particle shapes and to compute directly some structure-dependent physical properties (such as liquid permeability, mechanical strength/ stability, compaction and sintering, dissolution and leaching, etc.) is obviously highly desirable and has significant potential in industrial applications. Examples are presented relating to the packing of granular materials.

Jan 1, 2003