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By A. Qaredaqi, M. Mohammadi

Wet High Intensity Magnetic Separators, for short, WHIMS are used for recovery of Iron ores with low magnetic susceptibility. A Jones patent WHIMS with "grooved plates" matrix is being used in Dry Tailing processing line in Hematite Recovery Plant at Golgohar mining & Industrial Co. for recovery of Hematite. In this kind of separators Matrices are used for increasing the Magnetic field intensity and providing high magnetic field gradient. The laboratory WHIMS in Golgohar Iron Ore and Steel research Institute is capable to provide a background magnetic field strength up to 0.85 Tesla and in presence of ‚expanded metal? matrix, magnetic field intensity could increase up to 0.9 Tesla. More than 50% of feed particles in this separator were finer than 36 micron and recovery of these particles needs more magnetic field intensity. Hence, ‚Grooved Plates? matrices with Js= 2 Tesla and 3.8 mm gap were constructed. Measurements indicated that magnetic field intensity around the matrix will increase to 1.25 Tesla. Graph of Magnetic field intensity around the matrix to background magnetic field intensity was plotted and a model with Rsquare= 0.9 was offered. In addition, magnetic field gradient and magnetic force were calculated. In WHIMS with feed top size of 150 micron, the main effective forces on separation process are the magnetic force and the hydrodynamic drag force. With assuming that the particles are smooth and spherical and the flow is laminar, Recovery of fine magnetic particles is problematic in this separator because of drag force. Considering these facts and mentioned model, finest particles that are recoverable in different magnetic field intensities were calculated. Computations illustrated that with magnetic field intensity more than 0.8 Tesla, particles as fine as 4 micron are theoretically separable but it should be noted that in practice a larger attractable particle size would be expected.

Jan 1, 2014

By Y. J. Ferdosi

This paper presents the outcomes of the preliminary investigation focused on the potential usage of Electrochemical Impedance Spectroscopy (EIS) in minerals processing. Currently, Electrochemical Impedance Spectroscopy has been successfully employed in the characterization of multilayer structures formed as molecules adsorb on flat surfaces and is commonly used in bio-related research. Few studies have explored the application of EIS in minerals processing, particularly for mineral particles and flotation systems. In the first series of tests, the impedance response was investigated as a function of particle size, shape and hydrophobicity using model quartz particles. The particle size fractions and the shape were found to contribute to the impedance response. The more hydrophobic quartz particles resulted in a higher impedance values. Further tests involved pure sulfide minerals including chalcocite, bornite, chalcopyrite and pyrite. The AC impedance measurements were conducted as a function of collector (sodium ethyl xanthate) dosage. The AC Impedance data was modeled using the combination of reference circuits. It has been shown that adsorption of collector onto sulfide minerals surfaces results in a higher magnitude of impedance. Increasing the collector dosage resulted in an increase in AC impedance for chalcopyrite, while a decrease was observed for chalcocite. Significant variations in impedance were exhibited by bornite and pyrite with a gradual increase in collector dosage.

Sep 1, 2012

"Wet low intensity magnetic separation has been used for the recovery of magnetite for decades. As high-grade reserves continue to decline, low grade magnetite ores are being targeted for iron production. Low grade magnetite mineralisation is typically fine grained and requires fine to ultrafine grinding (P80 40 - 30 µm) to liberate it from, predominantly, silica/silicate gangue matrices. Grinding to such particle sizes requires high power consumption and produces excessive fines which impact negatively on wet magnetic separation and tailings dewatering. In addition, the dearth of fresh water for mineral processing in arid areas impacts negatively on the economic viability of low grade magnetite projects. These challenges have motivated innovation in dry magnetic separation technologies for the beneficiation of magnetite that can be economically applied on a large-scale. Such technology has been developed in the Cyclomag Planar magnetic separator (PMS) invented by South Australia-based Christopher Kelsey of IMPTEC P/L. The significant gangue mineralisation associated with magnetite ores in South Australia is quartz. In this study, the performance of the Cyclomag PMS on the recovery of magnetite mineral from magnetite-quartz blends was investigated. Magnetite-quartz blend were subjected to the PMS at varying control parameters - magnet discs rotation speed, inlet airflow and feeder speed. The study showed a successful dry separation of magnetic mineral from non-magnetics using the Cyclomag PMS. The PMS has potential to effectively recover magnetite mineral."

Jan 1, 2018

By Lei Pan, Roe-Hoan Yoon

"Direct force measurement for bubble-particle interaction has been difficult due to bubble deformation, which makes it difficult to know the separation distances between the two macroscopic surfaces. In the present work, we have developed a method of monitoring the deformation accurately, while directly measuring the interaction forces. In effect, we can ‘see’ bubbles interacting with mineral surfaces under different hydrodynamic and chemical conditions and determine both the hydrodynamic and surface forces involved. In the present work, a high-speed camera has been used to record the optical interference fringes of a thin liquid film (TLF) of water formed on a mineral surface. The recorded fringes are then used to reconstruct the spatiotemporal profiles, from which one can determine the hydrodynamic pressure using the Reynolds lubrications theory. From the forces directly measured in the present work and the hydrodynamic pressures obtained from the fringes, we have determined the disjoining pressure. The results show that air bubbles interacting with hydrophilic surfaces form stable TLFs with zero contact angles. The TLF formed on a hydrophobic surface thins fast, form a ‘pimpled’ film, and ruptures to form a finite contact angle. The new information obtained in the present work may be useful to better understand the role of hydrodynamic and surface forces affecting bubble-particle interactions."

Jan 1, 2014

By Sanja Miskovic, Manjunath Basavarajappa

In this study, a coupled CFD-DEM (Computational Fluid Dynamics-Discrete Element Method) approach is used to simulate two-phase, solid-liquid flow within the flotation cell. Turbulence plays a key role in flotation cells and level of turbulence is affected locally by the presence of particles. Turbulence in the flow is modelled using Reynolds Averaged Navier-Stokes (RANS) based k-e model. Using particle transport and spatial distribution, mixing mechanism for differed sized particles are analysed. By including the effects of particle-particle collision, particle rotation, and particle translation, as well as the volume occupied by the particles in the fluid, CFD-DEM approach can be used to accurately predict the motion of particles in the turbulent solid-liquid flows with strong coupling. Electrical resistance tomography (ERT) is used to investigate the effect of impeller size, shape, off-bottom clearance and impeller speed on mixing and suspension behaviour inside flotation cell. The effect of flotation impeller design, impeller size, and off-bottom clearance on flow hydrodynamics is investigated. In the case of moderate and high solids loading (> 10 %w/w), energy is dissipated through inter-particle interactions and four-way coupling becomes important (Derksen 2003). The main goal of this study is to understand the effect of particle size and concentration on flow dynamics at high Re in highly turbulent systems using advanced modelling and measurement techniques. Experimental measurements obtained by ERT) system allowed detailed mapping of temporal hold-up profiles of the dispersed phase. Impeller size and off-bottom clearance are found have significant effect on the particle suspension characteristics.

Jan 1, 2014

By M. E. Holuszko

This paper reports the results of induction time measurements carried out on the products of film flotation of galena and sphalerite particles from three different size fractions (38~75µm; 75~150µm; 150~212µm). As expected, the tailings (sinking fraction) from film flotation at any particular surface tension, had always longer induction times than the concentrates (floating fraction), for both minerals. The difference between the induction times of film flotation concentrate and tailings could be as little as 2.5 ms and 5 ms, and as large as 6 ms and 10 ms. These differences can be related to the different hydrophobic characteristics of these fractions, as expressed by (?c) and composition of the particular film flotation product. In addition, the induction times of the larger particle size fraction were shown to be longer than for the corresponding smaller particle size fraction, even though the average ?c(degree of hydro-phobicity) of these fractions appears to be very similar. Desliming, Cu activation and collector addition to the sphalerite samples was shown to decrease the induction time values significantly.

Jan 1, 2014

By L. Weitkämper

The big challenge at present and in the future is the economization of resources. This is applied for the whole industry but particularly in fields of mineral processing. The most important resources are energy and water. The shortage and price advance of energy is worldwide noticeable whereas the shortage of water is regionally limited at present. However due to the increasing world population, associated with a rising standard of living, water will become more and more important. Studies of the Unesco from 2001 indicate that the total water consumption raised seven times since the last 100 years at a growth of population of just three times. (UNESCO-Currier, 10/2001). This trend is going to be increased. While today more than 90 % of the humanity has access to clean water, in 2050 just about 50 % will be in the same situation. These figures indicate the importance of a gentle handling with the resource water. Further more the disposal of fine products, containing most of the water, is an environmental concern and in the future the mining and processing of raw materials will become important and necessary in desert, arid or permafrost areas. In these areas just efficient dry cleaning technologies will allow an economical beneficiation or better enable the processing at all. Most of the separation technologies with high throughput rates in mineral processing are based on wet processes. This applies especially for the separation of fines. Though there are some dry technologies available for the separation of coarse materials, like pneumatic gravity separation [air jigs and air tables], magnetic separation and not least sensor based sorters. Dry separation of fines is bounded mostly on cost intensive and low throughput technologies. The pneumatic separation undergoes at present a renaissance, mainly due to the development of the all air jig by the German supplier Allmineral. This newly developed sorting device yields good results in the separation of coarse to medium size material. All these facts and figures show the potential and motivation for developing an efficient dry separation device for fines. The following article delineates the development, performance and chance of a new dry separation technology for fines.

Jan 1, 2014

By Luis Bergh, Juan Yianatos, Luis Vinnett

"Process automation as an engineering discipline is more than control systems since it includes industrial instrumentation, such as sensors, transmitters and actuators, as well as control and supervision systems, collection and transmission of data and real-time software applications to supervise and control the operation of plants or industrial processes. In the last several decades, accelerated technological development has provided a variety of software and hardware tools to aid development, maintenance and continuous improvement of automated systems. These developments however seldom reach their full potential in real plants. There are many factors to be considered, among them human capital specific training and the organization model. In this paper, a methodology for training engineers in advanced control and supervision of flotation plants is presented based on study of the application of these technologies in hybrid pilot plants. Since experimentation in real plants may present undesirable risks and costs, and simulation studies are usually limited to some unrealistic conditions, a laboratory where on-line measurements of the hydrodynamic behaviour of a pilot plant is mixed with phenomenological models has been created. In this form, an environment as close as possible to a real plant can be recreated. A flotation column and a circuit of three pneumatic cells are fully instrumented and connected to a PLC and PC network. In the control room, students learn applications of classical PID control in a DCS environment, advanced predictive control, on-line process operation diagnosis, fault analysis, virtual sensors and expert-fuzzy systems. Several undergraduate and graduate courses and theses are supported by this Process Control Laboratory infrastructure. Examples of these applications are discussed."

Jan 1, 2014

By W. Pawlos

"The paper will present the methods of visual observation and recording of movement paths of coal grains of different physical properties in the paramagnetic liquid. The paths were recorded with a video camera in the working chamber by means of a specially constructed device, acting as a periscope, which were then transformed into digital images.Experimental movement paths were confronted to the paths obtained in a theoretical way by means of solving differential equations of movement. The outlet level of a grain of the same physical properties from the separator is a random variable with normal distribution which modal value is equal to the outlet level of a spherical grain, calculated from the solution of grain movement equations. At these assumptions it is possible to calculate the height of the passage from the separator working chamber to separate a given product with a given separation accuracy, measured by a probable error and to determine separation conditions."

Jan 1, 2003

By M. Niinae

Electrokinetic soil remediation by electroosmosis and ionic migration is restricted to soluble sub-stances. At a higher pH, the soil particles sorb more heavy metals, such as cadmium, than at a lower pH and the precipitation reactions of heavy metals are promoted. Both mechanisms make heavy metals immobile, rendering clean up more difficult and electrokinetic extraction inefficient. There-fore, the acidification of soils is very important to increase the clean up efficiencies of heavy metals, such as cadmium by electrokinetic method from contaminated soils. In the present study, acidification of soils and cadmium transport are predicted with a numerical method in which electrical flow is coupled with hydraulic flow, and the sorption process in the soils is induced in the model. The effects of some factors such as electrode configuration, electric field strength and electrode spacing for saturated soils are investigated using this numerical model. The results obtained this study are summarized as follows: The two-dimensional electrode configurations containing cathode surrounded by three or more anodes rapidly acidify the soils and remove cadmium from soils compared with one-dimensional electrode configuration. However, two-dimensional electrode configurations develop spots of inactive electric field between cathodes. A larger electrode spacing increases the processing time required, and it was also found that a larger electric field strength reduced the processing time required.

Jan 1, 2014

By M. Ito

Cobalt-rich ferromanganese crust and nodule ores from seamount areas contain volcanic and sedimentary rocks as substrate or nuclei and these ores require mineral processing to remove the substrate/nuclei rock before smelting. This paper reviews the results of jig separation and air table treatment for the coarse fraction and flotation and hybrid jigging for the fine fraction. Using these techniques substrate/nuclei rock was removed from the cobalt-rich ferromanganese oxide components. The mineralogical properties and metallurgical treatment methods including hydrometallurgical treatment of low grade ore is also reviewed.

Sep 1, 2012

By Matthew Thurley

Optimisation and control of comminution, pelletization, and agglomeration processes is a complex task with large potential for gains in productivity, energy efficiency, and particle size distribution quality. One factor in realising these gains is the requirement for fully-automated online particle size distribution measurement. Moreover, online particle size distribution measurement that is based on the particles on the visible surface and can avoid or mitigate substantial errors that result from under-sizing overlapped particles and over-sizing areas of fines particles. Literature review indicates a body of substantially 2D photographic based particle size measurement systems that suffer from a large number of significant errors except in the simplest case of a monolayer of particles under good illumination with limited color variation in the material. In order to measure the visible particles on a pile there are a number of requirements including; avoiding particle delineation errors due to variation in material color and shadows, detect overlapping versus non-overlapping particles, and identify areas of fine particles as fines and not large rocks. Results are presented using a fully-automated online measurement system of crushed rock on conveyor belt using a 3D surface laser profile. The system provides continuous online measurement and results are shown on over four hours of production after the primary crusher. Size distribution results are calculated using volumetric estimation of the particles on the surface of the pile. The results show a strong capability to discriminate size variation especially in the 10% and 20% passing values. Furthermore results show that if areas of fines are misclassified as large rocks, and overlapped particles misclassified as small rocks, then a near complete loss of discrimination occurs for the P10 and P20 values which become largely constant values.

Jan 1, 2014

By Lawrence Bbosa, Aubrey Mainza, Indresan Govender

"Positron Emission Particle Tracking (PEPT) and the Discrete Element Method (DEM) are used to develop a probability based model for the power draw of a tumbling mill. Experiments are conducted using dry spherical glass bead charge in a laboratory scale tumbling mill, which is mounted with a torque transducer and tachometer to measure mill power. Particle tracking information from PEPT is used to reconstruct the motion of glass beads and infer the overall charge behavior, while DEM is employed to simulate particle motion and interaction, with collision mechanics calculated using the Hertz-Mindlin contact model. For both sets of data, the product of torque and average angular velocities in discrete cells are accumulated to obtain mill power. This method is found to be within statistical agreement with measured power for all tests. The information from both techniques is then used to develop a model for the power draw as a function of particle size, mill speed and volumetric filling. Predictions of the model match well with measured and calculated values. The model is found to predict mill power within close agreement with measurement and follows trends consistent with existing work on tumbling mill modelling."

Jan 1, 2014

By W. Z. Zu

In proved reserves of vanadium-containing titanomagnetite in Panxi, China, iron grades of ores were 50% ~ 15%. China?s metallurgical industry departments defined the iron ores containing 50% ~ 20% TFe as exploitable resources and the extreme lean iron ores containing 20% ~ 15% TFe as temporary unexploitable resources, the extreme lean ores were as waste rejected into waste dump in mining process. This paper researched process mineralogy of the extreme lean ores, adopted mineral processing technology responded to the properties of the ores to treat the ores and obtained quality vanadium-iron concentrate, titanium concentrate and sulfur concentrate, therefore successfully utilized the extreme lean ores, changed the ores from waste resources to exploitable resources.

Jan 1, 2014

By Dave Deglon

The Western Cape Mineral Processing Facility (WCMPF) is a collaborative educational initiative between the Departments of Chemical Engineering of the University of Cape Town, the University of Stellenbosch and the Cape Technikon. The WCMPF was established in 1989 with the aim of improving mineral processing education in the Western Cape. Since its inception the WCMPF has had a number of successes in this area, especially in improving the quality of mineral processing practical training. In addition, the WCMPF has played an important role in promoting liaison and interaction between tertiary educational institutions teaching mineral processing in the Western Cape. Over the past decade the WCMPF has played a key role in the education of over five hundred mineral processing graduates and diplomates. This paper presents an overview of the activities of the WCMPF and attempts to encapsulate the ‘lessons learned’ from over a decade of successful functioning as a collaborative educational initiative in mineral processing.

Jan 1, 2003

By Felipe Sepulveda, Edelmira Gálvez, Luis Cisternas

"In mineral processing, the recovery and/or concentration of the value components cannot occur in one operational stage, therefore requiring the use of separation circuits based on several flotation stages. The components to be separated are typically distributed at different concentrations and different particle sizes, resulting in different levels of recovery. Typically, more than one value component must be selectively removed by exploiting the differences in the components’ floatability at different pH values, pulp potential and particle size. Several methods for the design of these circuits are available in the literature, but comparatively few studies present circuit analysis tools or address the design of a multiple-product flotation circuit. In this study, global sensitivity analysis was used to analyze a flotation circuit with several products, such as copper, lead and zinc. This analysis was based on the Eureka mine concentrator plant. The analysis was performed for each of the sections of the circuit as an overall evaluation of the circuit. The Sobol’ method and the correlation method were used to evaluate the Eureka mine concentrator plant using the SimLab 2.2 software."

Jan 1, 2014

By A. Norori-McCormac

"Air recovery, the fraction of air entering a flotation cell that overflows the cell lip, is linked to flotation performance, and it has been shown through industrial testwork that operating flotation cells at air rates that yield the Peak Air Recovery (PAR) results in high mineral recovery. For operating parameters over which flotation plants have little control, such as particle size, investigating the effect on the position of PAR, and the subsequent effect on flotation performance, proves more challenging. To this end, we have developed a bench scale flotation system that runs continuously and exhibits froth behavior similar to that found industrially, allowing the study of such parameters as particle size in addition to air rate. The bench scale system comprises a 4 l baffled cylindrical flotation cell, stirred by a Rushton impeller. The concentrate is recycled back into the pulp, allowing for continuous operation. Glass beads are used as solid particles, allowing a wide range of particle sizes to be tested, with TTAB as collector and MIBC as frother. The system allows operation at air rates typical of industrial flotation systems (1 -2 cms-1 superficial gas velocity), in addition to yielding a froth that coalesces and bursts and exhibits a peak in air recovery as cell air rate in increased. Solids and water recovery is also measured. The results show that air recovery is sensitive to changes in particle size. The intermediate size distribution showed a peak in air recovery (PAR) that corresponded with the maximum solids flowrate, as found industrially. It is shown that finer particles do result in more stable froths and higher recoveries, particularly at low air rates. The effect of particle size on the position of PAR is not yet unequivocally determined from these results."

Jan 1, 2014

By A. Kamali Moaveni, A. Boehm

"The current research study addresses a physical separation process of basic oxygen furnace slag “BOF-Slag” (also called Linz-Donawitz “LD” slag) for the removal of phosphorous. In order to recycle the LD-Slag into the steelmaking process, the physical dephosphorization methods are considered. The systematic geometallurgical investigation carried out on particle classes of decreasing size, which were further subdivided into susceptibility classes, shows intimate intergrowth beyond 40 µm due to slag´s fast cooling rate. Generally, LD-slag is constituted of oxide and silicate phases, among which di-calcium silicate “C2S” dominates. About 0.5 mass% of phosphorous was detected in the LD- slag, which is exclusively situated in the lattice of the C2S. The comparatively high grinding resistance (Rittinger index 12.9 cm²/J) of the LD-slag reflects the energy demand to liberate the phosphorous carrying phase from the iron containing minerals, while separation efficiency decreases in the very fine particle size range. Hence, the conversion of the phase intergrowth pattern was considered alternatively to re-build the mineral phase structure of the material to a separable interlock pattern. Carbon dioxide, as the most convenient substance in the steelmaking plants, was applied to digest the C2S in the presence of water and to reduce the basicity of the slag slurry. As a result of C2S-CO2 chemical reaction, calcite and calcium silicate are precipitated at the surface of the oxide particles and carried between 25% and 75% of the total phosphorous, respectively. Accordingly, the mobility of the phosphorous content phase to the top of the grains serves the possibility to separate the precipitated layer by mechanical attrition process. This paper is focused on the impact of the intergrowth pattern alteration on the slag´s separability characteristics. Moreover, the operating conditions of the carbonization process, such as temperature and pressure, on the deconstruction kinetics of the C2S and the generated products will be considered. INTRODUCTION The steelmaking BOF-Slag is a stony aggregate waste from the steel manufacturing process. The investigated slag by the current research work was provided by voestalpine steelmaking plant in Linz, Austria. The current legislative situation in Austria restricts the historical application of slag as construction material, due to the high level of heavy metals content and corresponded land-filling and transportation costs of slag, therefore the demand for recycling of BOF-Slag to the steelmaking process has raised, as an alternative application. Statistically, voestalpine steelmaking plant produces about 130 kg BOF-Slag per ton of final steel product, which serves annual BOF-Slag production of 700,000 ton, approximately."

Jan 1, 2018

By S. Narra, M. Nelles, I. Eickhoff, S. Teitge

"The aim of the research is to develop a holistic process flow for the recycling of glass fibres from glass reinforced plastics (GRP) and carbon fibres from carbon fibre reinforced plastics (CFRP), wherein the dissolution of the fibre epoxy resin matrix, separation of fibre fractions and their renewed material use is intended. In clear distinction to the previous research and development projects, the aim here is to recycle complex composite structures such as dismantled/disused wind turbine rotor blades and end-of-life composite wastes. In the course of the study, mechanical, hydrothermal and thermal processes and their combined procedures will be developed. As the fibre length is a decisive quality criterion in the recycling of composite materials, the further focus of the study will be the development of upstream and downstream material processing, in which the fibres are retained in their original form. The evaluation of the recycled fibres obtained is based on the elemental composition, measurement and morphological evaluation of individual filaments by scanning electron microscope (SEM), micro tensile tests on single fibres and their comparison to virgin fibres. The resulting process water is analysed by gas chromatography and mass spectroscopy (GC-MS) and a potential recirculation is determined. In cooperation with companies from the composite processing industry as well as recycling companies, a return of the recycled fibres to the known manufacturing process will be examined and an energetic and economic evaluation of the overall process will be carried out. Ambitious aim of the study is to achieve an actual recycling instead of the present downcycling or the energetic utilization. INTRODUCTION As global warming increases, so does the awareness of consumption and production of energy. To counteract the effects of global warming, renewable energy has been increasingly used during the last two decades, not only in Germany, but worldwide. Both, hydropower and wind energy, hereby play a fundamental role. After the end of their useful life of 20 to 30 years, the wind turbines (WTs) are being dismantled. Due to their foundations and tower segments, their recycling rate hereby exceeds 90% by mass. So far, the resulting rotor blade waste played a minor role accounting for only 2 - 3 weight-% of the total plant. Rotor blades of modern wind turbines are made of glass and carbon fibers, which are embedded in an epoxy or polyester resin matrix, balsa wood, PU or PET foams as fillers as well as various paints and coatings. These wastes currently end up in waste incineration or are sold to non-European countries."

Jan 1, 2018

By M. Rudolph, D. H. Hoang, N. Kupka

"Froth flotation has been subjected to modelling since the 1930s and there is a large variety of approaches that intend to portray the entire process. Among these, three fundamental models could be considered exhaustive: the Pyke model [1], the Yoon model [2] and the Schwarz and Koh model [3]. The first model makes use of the generalized Sutherland equation collision model, the Dobby-Finch attachment model and its own stability model, the second model considers an extended DLVO approach for the attachment and stability whereas the third model makes use of computational fluid dynamics. Using a scheelite ore as a test case, a specific batch flotation test was repeated ten times and analyzed for chemical assays, mineralogical studies and froth properties. The detailed data are used to feed the three flotation models aforementioned in order to compare the outcomes of the three approaches, their capacity to reflect reality and to predict it. This article intends to pave the path towards reliable process models incorporating in depth mineralogy information, e.g. surface liberation, particle size and particle shape. KEYWORDS Froth flotation fundamental models, scheelite, automated mineralogy, critical assessment. INTRODUCTION In mineral processing, only three approaches aiming at describing froth flotation fundamentally could be considered exhaustive: Pyke’s collision and sliding approach [1], Yoon’s kinetic approach [2] and Schwarz and Koh’s approach [3]. The models will hereafter be referred to as Pyke model, Yoon model and Schwarz and Koh model. The first model makes use of the generalized Sutherland equation collision model, the Dobby-Finch attachment model and its own stability model, the second model considers an extended DLVO approach for the attachment and stability whereas the third model makes use of computational fluid dynamics. All three approaches rely on the widely accepted idea that flotation is a kinetic reaction dependent on a flotation rate constant kp, as expressed in Eq. [4]:"

Jan 1, 2018