Coal Preparation

A Coal Spiral for the 2020s

The objective of this project is to develop an enhanced coal processing spiral, which incorporates learnings from recent improvements in spiral design that have been implemented in other mineral processing operations.

Baseline testing was conducted on coke and thermal coal feed types, ....  read more

Wash Plant Fines Testing Methods Enhancement

Accurately estimating the proportion of expected fine size material (typically -1 to -0.125mm) from coal borecore exploration is critical to design and operation of coal handling and preparation plants to process the coal, and in resource predictive potential and economic outcomes.

Improving flotation with a combined method

This project aimed to develop and assess a method combining the use of oscillatory air supply and acoustic sound for improving coal flotation. The approach was based on the dynamic stabilisation effect induced by exposing the froth phase to low frequency acoustic sound and the decrease in the ....  read more

Optical Profiling of Coal and Mineral Particles in the Ultrafine Circuit for Online Analysis

This project was based on adapting the Particle Profiler system for ultrafine coal streams such as flotation circuits and thickener feed. The current Profiler system captured images of particles (0.1 - 2mm) settling in water and tracks them to measure the average size and speed of each ....  read more

Full-scale Studies of Diesel Emulsification by Ultrasonication for Fine Coal Flotation

Froth flotation is widely used to recover fine coal in the industry. Diesel is commonly used to increase coal hydrophobicity for efficient coal flotation. However, the oil based collector does not self ionize and does not dissolve readily in water with some mixing required to disperse the oily ....  read more

Full Scale Trial of the REFLUX™ Flotation Cell

A 2 m diameter REFLUX Flotation Cell™ (RFC™) was installed at a Hunter Valley mine site and successfully operated during several campaigns in 2021 and 2022. The technology delivered strong performance comparable to or better than the tree flotation curve across a wide range of feed ....  read more

Measuring and Correlating CGA Data at Particle Topsize

Coal Grain Analysis (CGA) is gaining some traction as an alternative way to characterise a coal, and it is usually undertaken on a sample of 1 mm topsize, as per a conventional petrographics analysis. In prior work, samples of up to 4 mm topsize have been successfully analysed using CGA. This ....  read more

Froth flotation of 4 mm coal particles

In the Australian coal industry, flotation is used in the final stage of coal preparation, to recover fine particles with a typical top size of 0.25 mm. Particles of screen sizes between 2 mm and 0.25 mm are usually treated using gravity separators such as spirals, teeter-bed separators, or ....  read more

Development of a Model-Informed Control Strategy for Coal Flotation in a Jameson Cell

Jameson cells are often used in a coal processing plant to treat the ultrafine coal (-250μm) and reduce the ash content of the final product. However, it is not uncommon for these cells to be poorly controlled leading to unnecessary loss of combustibles to the flotation tailing stream. ....  read more

Better Classifying Cyclones

Despite classifying cyclones being important coal preparation plant workhorses that effect fine coal particle mixture component separations, project C27012 did not identify any near term potential technological improvements on the horizon.

The Rong Classifying Cyclone Concept ....  read more

Fine Coal Centrifuge Dewatering Test

Dewatering of fines is problematic due to the high surface area and the varied nature of the feeds to the various centrifugal dewatering machines. In particular, tailings containing different clay types and amounts can reduce the capacity and increase the cake moisture of the dewatering ....  read more

Developing a Frother Decision Tree for Australian Coal Flotation Plants

Methyl isobutyl carbinol (MIBC), an aliphatic alcohol frother, has been widely used in Australian coal flotation plants. However, MIBC can cause health, safety and environment problems due to its low flash point and high evaporation rate, and therefore it has been under safety alert from the ....  read more

Ultra-Low Ash Coal by 3D Binder Flotation

The objective of this project was to investigate the potential to produce a coal‐water mixture fuel, ideally less than 1 wt% ash, through liberation by grinding, followed by beneficiation via a novel agglomeration method referred to as 3D Flotation. Different levels of grinding were used ....  read more

Quantifying the Step-Change Benefit of Reflux Flotation Cell Circuits

The objective of this project was to quantify the value proposition of applying the Reflux Flotation Cell (RFC) to identified applications, utilising a broad range of feeds supplied by producers. Laboratory scale RFCs were used to obtain the data. The potential for complete recovery of ....  read more

Reducing Diesel Consumption While Improving Fine Coal Flotation Through Controlled Diesel Emulsification in Saline Water

Diesel collector used in coal flotation is not soluble in water and therefore has a low efficiency in dispersing in coal slurry and adsorbing on coal surfaces. Previous research found that coal flotation can be significantly improved through diesel emulsification in water. However, the ....  read more

Phase Two Development of a Low Cost Online Measurement of Particle Size and Density for Diagnostics Across the Fine Coal Circuit (Particle Profiler)

This project is based around the development of a prototype system (Particle Profiler) for online analysis of coal quality in the fine circuit of a coal preparation plant (ie in the range of -2+0.125mm). The system determines the distribution of particle size and density using an optical ....  read more

Effect of Chemicals on Stabilising Tailings Disposals of Coarse and Fine Coal Rejects

The risk of potential catastrophic liquefaction failure and costs associated with tailings storage facilities  is reduced substantially by co-disposal strategies, i.e. disposing of a dried mixture of coarse and fine coal tailings rejects. This process involves dewatering of fine rejects ....  read more

Impact of Sub-optimal Performance

The inclusion of the Sub-Optimal Operation (SubO) / Health Issue (HI) is the starting point in 'The Intelligent Plant' Diagnostic System and to enter this diagnostic system from a health issue (Hid), a sub-optimal event, the linkage maps needed to be changed. The focus of this project ....  read more

Towards Better Fine Coal Classification

It is well recognised that the efficient classification of fine coal in the range of 0.04 - 0.3 mm is a key technology area to improve the efficiency of coal preparation. ACARP has invested substantially in the area of fine coal classification, and in order to maximise the benefits of past ....  read more

Adaptation of Coal Grain Analysis to Improve Flotation Yield Estimation

This project involved sampling of full-scale flotation circuits at each of six different coal preparation plants, each subject to three different reagent dose rate regimes (three sampling runs per site). Coal Grain Analysis (CGA) was undertaken on feed, concentrate and tailing for each run. ....  read more

Comprehensive Flotation Model Using CGA Particle Surface Composition

The aim of this project was to adapt existing particle based flotation circuit simulation architecture, developed by the Julius Kruttschnitt Mineral Research Centre for metalliferous flotation circuits, as a tool that can be applied in fine coal flotation to forecast the likely impact changes ....  read more

3D Flotation of Fine Particles

In this project a process for the continuous, selective agglomeration and recovery of fine coal was designed and investigated. The agglomeration was achieved using a binder consisting of a highly concentrated water in oil emulsion. The binder, which was developed in a previous ACARP project, ....  read more

Performance-Enhanced Diesel Collector for Coal Flotation

The objective of this project was to carry out coal preparation plant based trials of the performance enhanced diesel collector for increasing the combustibles recovery of both coarse and fine coal particles and/or reducing the consumption of diesel oil while maintaining good flotation ....  read more

Plant Scale Testing of Safe Aerosol Frother Addition to Reduce Residual Frother and Reagent Costs

The use of frothers in the froth flotation process is essential in achieving acceptable process performance through the formation of sufficient numbers of stable bubbles to maximise particle-bubble contact and bubble surface area to carry hydrophobic particles to product.

Frother has ....  read more

Rapid Extraction of Frothers from Process Water

The purpose of this study was to address the problems associated with excess frother in the process water of coal preparation plants. The goal was to establish an approach for recovering up to 50% of the frother from the flotation tailings. The frother concentrate would then be recycled back ....  read more

Evaluation of Residual Frother Minimisation Strategies

This project was undertaken to quantify the effectiveness of a number of approaches recommended for minimising unwanted frothing caused in part by residual frother in process streams in coal preparation plants.  In order to be able to make these assessments, a rapid, portable frother ....  read more

Full Scale Gravity - Desliming Using Cascading REFLUX Classifiers

Considerable quantities of fine coal are disposed of as part of the tailings from coal preparation plants and there are also large inventories of fine coal in existing tailings dams. The recovery of such coal by flotation is not always possible or economic and the applicable size range of ....  read more

Adaptation of Coal Grain Analysis to Improve Flotation Yield Estimation

Yield estimation from resource data is notoriously difficult. Factors impacting on achieved yield include:

• CPP feed size distribution which directly affects washability distribution;
• amount and nature of dilution;
• actual flotation response (subject of this

Leveraging Detailed Maceral Component Information from CGA

Since Project C18041 was completed, the CSIRO image analysis software has been transitioned and more detailed information is able be generated by further extending and re-coding the software calculations. This allows previous images to be re-analysed to extract additional information of ....  read more

A New Approach to Coarse Flotation

There are significant coal losses in flotation due to oversize particles entering the flotation circuit, usually due to worn screens. Conventional flotation fails to recover a significant fraction of these coarse particles, typically larger than 0.5 mm. A robust plant design requires unit ....  read more

Flotation Tailings Online Measurement

Online analysers can be used to assist in improving the performance of flotation circuits. Historically several different devices have been used in this application measuring an assortment of operational performance elements with variable success. This project evaluated the capability of the ....  read more

Comparison of Column and Mechanical Flotation Technologies

Fine coal beneficiation is virtually essential for coking coals unless the raw coal is of extremely low ash value, i.e. 10%. Most steel mills seek to have no more than 12% ash in coke and therefore selectivity in beneficiation is more important for lower ash coking coals than for thermal coals ....  read more

A Pilot Scale Study of Fast Flotation

In many coal preparation plants, beneficiation of the fine coal from the cyclone overflow is deemed uneconomical hence this stream has been sent to the thickener, and then onto tailings. Our objective was to establish a low capital cost solution to generate high value product from the cyclone ....  read more

Fine Coal Agglomeration using a Novel Economic Binding Agent

In this project a novel economic binding agent was investigated for use in the agglomeration of fine coal. The novel binding agent was a high internal phase (HIP) water-in-oil emulsion and it was to substitute the pure oil traditionally used in coal agglomeration processes. The substitution was ....  read more

Coarse Particle Flotation for the Plant of the Future

At present, there is no single device for the recovery of coal from feed materials less than 2 mm in diameter. Fine particles are usually separated in two stages. Gravity separation is used for particles in the range 300 µm to 2 mm, followed by froth flotation for the fraction below 300 µm. It ....  read more

Improving Coal Flotation with Oscillatory Air Supply

This report provides detailed information on coal flotation with oscillatory air supply at laboratory scale. The oscillatory air flow was generated from steady air flow by using two different devices. The majority of the coal flotation tests were carried out for different coking coal samples ....  read more

Simultaneous Gravity Separation and Desliming of Fine Coal - A Novel Concept

The purpose of this work was to examine a novel concept for achieving simultaneous gravity separation and desliming. The novel concept was the application of the dense medium effect within an Inverted Reflux Classifier. This device, which consists of a system of inclined channels below a ....  read more

Online Particle Size Monitoring in Coal Preparation

The principle of using laser diffraction as a means of measuring a volume size distribution in slurry is well established. Laboratory devices have been in use since the 1960's for monitoring ultrafine solids in cosmetics, pharmaceuticals, paper manufacture and minerals processing.

Measurement and Control of the Reflux Classifier

The purpose of this investigation was to establish the optimum control regime of the Reflux Classifier for coal sourced from various seams. Experiments were carried out at a CHPP in the lower Hunter Valley using an RC300 with six pressure probes installed along the vertical section and fitted ....  read more

Characterisation and Flotation of Oxidised Coals

Coal oxidation has deleterious effects on coal flotation. Using the conventional reagents suitable for floating non-oxidised coals, mild coal oxidation reduces the combustible recovery from flotation while severe oxidation makes the flotation impossible. To help the coal preparation plants to ....  read more

Full-Scale Trial of the REFLUX Classifier to at least 4mm Top-Size

Previous laboratory and pilot‐scale test work in ACARP Project C16040 (Galvin et al., 2009) had established the potential of REFLUX™ Classifiers (RC™) to beneficiate coal particles up to 4 mm in size, and even up to 8 mm in size, at separation efficiencies comparable to that ....  read more

Improving the Treatment of Clay Minerals in Coal Flotation in Saline Water

Clay minerals commonly occur in Australian coal deposits and have deleterious effects on coal flotation. Firstly, clay minerals can adsorb on coal particles as slime coatings and reduce coal surface hydrophobicity, resulting in a lower combustible recovery. In addition, clay minerals can be ....  read more

Impact of Sub Optimal Operation

The objective of this project was the 'Quantification the effects of sub-optimal operation' in a coal preparation plant. This was achieved by the analysis of particular operational issues and how they can affect the recovery of saleable coal.

Previous work in this area was ....  read more

Improved Flotation Recovery and Reduced Cost via Adjusting Frother Chemistry and Froth Behaviour

This report provides detailed information on a cyclic frother with high flash point and its coal flotation performance, two frother concentration measuring techniques, and a froth diagnostic tool.

Coal flotation tests at laboratory scale using mechanically agitated cell and Jameson ....  read more

Generalised Model of the Reflux Classifier using Computer Simulations Based on the Discrete Element Method

The aim of this project was to develop a generalised model of the Reflux Classifier (RC) utilizing a combination of a continuum approach based on the mechanisms of segregation and dispersion within the system, and a tracer particle approach based on the Discrete Element Method (DEM). The ....  read more

Enhanced Desliming using a Reflux Flotation Cell

The objective of this project was to investigate the potential to improve the desliming performance of fine coal flotation by using a Reflux Flotation Cell (RFC), and to establish increased certainty in the scalability from a laboratory scale unit to a pilot scale unit for future construction ....  read more

Improvement of Hydrodynamic Behaviours in Large Coal Flotation Cells

The performance of flotation cells can be impaired by the occurrence of unfavourable hydrodynamic behaviours, such as channel flows, pulp circulation flows, dead volumes and excessive shear stress. In ACARP project C21051, hydrodynamic behaviours in both Microcel columns and Jameson cells were ....  read more

Maximising Flotation Kinetics

Low pulp density and low grade streams in the coal and minerals industries are generally discarded to waste due to the low or negative financial return and large capital investment required. Yet, such losses to tailings dams are likely in the billions of dollars each year. The challenge facing ....  read more

Plant-based Investigations of Hydrodynamic Behaviours in Large Coal Flotation Cells

The performance of flotation cells can be impaired by the occurrence of biased feed distribution and unfavourable hydrodynamic behaviours, such as short-circuiting, pulp circulation flows, dead volumes or excessively high shear stress.

The hydrodynamics of a ....  read more

Improving The Performance Of Froth In Coal Flotation Using Saline Water

Froth stability is known to play an important role in determining mineral flotation recovery and selectivity. Overly stable froth causes high entrainment of gangue minerals in flotation and is difficult to handle in downstream processes. On the other hand, unstable froth is associated with the ....  read more

Improving The Treatment Of Clay Minerals In Coal Flotation Using Saline Water

Clay minerals present a widespread problem in the flotation of all kinds of minerals in that they can coat mineral surfaces resulting in low mineral flotation recovery, contaminate the flotation product through mechanical entrainment due to the small particle size and cause high pulp viscosity ....  read more

A Step Change in Fine Coal Beneficiation - Inverse Flotation

The objective of this study was to establish a major step change in the technology used by the coal preparation industry to beneficiate fine particles, especially particles smaller than 0.200 mm. We use the term “Inverse Flotation” to describe the new method of fine coal beneficiation. ....  read more

Small Diameter Cyclones for Desliming

In the Hunter Valley (HV), coal preparation plants often discard ultrafines < 125 micron because of the high clay and high ash content. Recovery of the coal that is currently lost in this fraction can potentially increase plant yield by 1 to 2 %. The use of small diameter hydrocyclones (100 ....  read more

Improved Flotation Recovery Via Hydrophobicity Adjustment-Extension

The main goal of this project was to examine the effectiveness of using new generation reagents for maximising the recovery of product specification coal during coal flotation. Previous work had indicated that coarse-sized inertite, inertinite-rich and vitrinite-rich composite particles are ....  read more

Application of Computational Fluid Dynamics Modelling to Coal Flotation

The work is an extension of a previous ACARP project C17038 in using the latest advances in computational fluid dynamics (CFD) to improve understanding of the hydrodynamics in coal flotation, and to improve the design and operation of the Microcel columns and Jameson Cells in existing ....  read more

Flotation Performance Monitoring By Acoustic Emissions

This project has provided proof-of-concept for monitoring of washery Jameson cell and Microcel column process state by passive acoustic emission (AE) methodology. Successful trials of an AE monitoring system developed at CSIRO were undertaken on a Jameson cell at Mt Thorley-Warkworth washery ....  read more

Baleen Filter Application

Every year millions of tons of good quality ultrafine coal are discarded along with the high ash slimes material onto tailings dams throughout Australia's coal mining regions. With Baleen Filter's new micro-screening technology, originally developed for the water treatment industry, ....  read more

Evaluation Of Eucalyptus Oils As Reagents In Coal Flotation

ACARP Project C16044 investigated the use of eucalyptus oils as both frother and collector in coal flotation. The application of eucalyptus oils as reagents in froth flotation dates back to the beginning of the process itself. It was realised early on that natural oils are complex mixtures of ....  read more

Improving Coal Flotation Recovery Using Computational Fluid Dynamics

This work involves using the latest advances in computational fluid dynamics (CFD) to increase understanding of the hydrodynamics in coal flotation and to identify any opportunities to improve design and operation of both the Microcel column and Jameson cell. The CSIRO CFD model incorporates ....  read more

Extending The Size Range Of The Reflux Classifier

A comprehensive study examining the potential of the Reflux Classifier to be applied to the beneficiation of coarser coal up to 8 mm in size was undertaken. It was established in this study that the Reflux Classifier can be operated successfully using a feed with an upper size of 4 mm and also ....  read more

0.100 - 0.200mm Cuts with Sieve Bends

The pilot scale performances of a 0.150mm aperture conventional and a 0.150mm aperture pressure sieve bend were assessed.   The slimes contamination level of the pressure sieve bend product was around ½ of that of the conventional unit.  This, however, was achieved at reduced ....  read more

Improved Flotation Recovery Via Hydrophobicity Adjustment

The main goal of this project was to examine a new approach to maximising the recovery of product specification coal during coal flotation using new generation reagents complemented by the use of the Coal Grain Analysis tool. The Coal Grain Analysis tool, developed by CSIRO, was used to ....  read more

Improved Efficiency of Fine Coal Classification

A proprietary water injector (WI) was installed and tested on a 1000 mm diameter hydrocyclone (classifying cyclone) at Rix's Creek Coal Preparation Plant in the Hunter Valley, NSW.

Water injection rates of up to 60% of the cyclone underflow water flow rate were evaluated.

Ultimate Froth Flotation Performance Test

This report describes the development of a new reliable method for determining the ultimate flotation response for 0 to 500 µm higher rank coals.  The method evolved from continuous development of laboratory flotation tests that were then compared to the “Standard” methods. By ....  read more

Improving the Monitoring and Control of Flotation Systems: Stages 1 and 2

The overall objective of this project was to develop an effective and inexpensive on-line monitoring system for the improved monitoring and control of fine coal flotation processes.

STAGE ONE REPORT

The specific aims of stage 1 are to investigate how the electrical ....  read more

Screening and Magnetic Separations for Fine Coal Dense Medium Plants

Since the early 1990s, there has been considerable development of the technology and equipment available for coal preparation which potentially can overcome the serious limitations identified in fine coal Dense Medium Cyclone (DMC) circuits. These limitations were poor size classification and ....  read more

Improved Classification Accuracy at 100 - 350 Microns

The pilot scale performance of the following different screen types has been assessed:

• A Derrick Stack Sizer™ ; Tested by Derrick Corporation in Buffalo, New York State
• A Kroosh high frequency screen; Tested by ACIRL Maitland, New South

Design and Operating Data for Fines Treatment

This project has generated a large quantity of detailed process efficiency information, on a size-by-size basis, for modern fine coal processing equipment.

This project is complemented by data from a parallel ACARP project (C12050) relating to detailed performance information ....  read more

Integrated Processes for Fine Coal Treatment

The construction and operation of an 80m3/hr flotation demonstration plant is described. The hypothesis that coal particles as coarse as 2mm can be effectively treated by froth flotation has been demonstrated on a plant scale. Excellent yields and combustible recoveries were achieved by ....  read more

Flotation Diagnostics by Coal Grain Analysis

In coal flotation, particles of different components of the coal such as maceral groups and mineral matter and their associations have differing hydrophobic characteristics and therefore different flotation responses. By using a new coal grain analysis method for characterising ....  read more

Improving the Recovery of Coarse Coal Particles in a Jameson Cell

The ACARP funding allowed the design of a production sized Jameson Cell test rig with internal sampling arrangements and for investigations into combustibles recovery under different Jameson Cell operating conditions.

Reduction in downcomer turbulence through operation with ....  read more

Scale-Up of Coal Flotation Using Picobubbles

The use of cavitation to enhance the flotation of minerals and coal has been studied over a number of years. Nicol et al. (1986) reported that the use of a superimposed acoustic field nucleated precipitation of extremely small air bubbles (picobubbles) on the surface ....  read more

480mm JKCC Study at Dartbrook CHPP and in the JKMRC Pilot Plant

A 480mm-diameter novel classifying cyclone, known as the JKCC, was tested at Dartbrook Coal Handling and Preparation Plant (CHPP) to assess its performance in an industrial environment. The JKCC was installed in a primary CC bank and operated together with other 480mm commercial CCs. The ....  read more

Investigation of the Reflux Classifier for Density and Size Separations from Pilot to Full-Scale

The Reflux Classifier is a new device for separating particles on the basis of either density or size. Water flows up through a distributor plate at the base, suspending particles within the vessel. A set of parallel inclined plates amplifies the segregation rates of the particles, ....  read more

Development of a New Method to Determine the Ultimate Flotation Response Curve of a Coal

The objective of this project was to develop a new test to determine the ultimate flotation response curve. The current method for doing so is known as a Tree Analysis Test and is covered by Australian Standard 4156.2.2 - 1998(1).

The effect of collector concentration, frother ....  read more

Aerosol Frother Addition in Coal Flotation

A frother is traditionally added to the flotation feed slurry prior to the introduction of air. There is the possibility of the frother being added to the gas-phase as an aerosol rather than via direct addition to the slurry. This is an approach which has received very little attention in ....  read more

Enhanced Coal Flotation using Picobubbles

The objective of this project was to provide a simple retrofittable device to enhance the flotation behaviour of poorly floating coals. A device capable of inducing cavitation in flotation feed generates very small "picobubbles" on the surface of coal particles, which have a greater affinity ....  read more

Small Coal Washability by Water Fluidisation

Galvin and Pratten (1999) have previously reported the technique of utilizing the density segregation effect of a narrow size range of particles in a fluidised bed to determine  ....  read more

Optimisation of Fine Coal Flotation

This project's objective was to assess the applicability of the flotation rate constant-bubble surface area flux (k-Sb) relationship to describe coal flotation, and its use as a means of characterising and optimising fine coal flotation (irrespective of cell technology).

Site work was ....  read more

Turboflotation Scale-Up - Stage 2

The overall objective of the TurboFlotation project was the development of an inexpensive compact process based on centrifugally enhanced flotation, capable of reducing the material residence time by an order of magnitude. The project was conducted jointly by the CSIRO Energy Technology Coal ....  read more

Froth Washing in Mechanical Cells

The objectives of this project were:

• To demonstrate the effectiveness of froth washing on full-scale conventional flotation cells.
• To develop design parameters for installation to any mechanical flotation bank.

Froth washing is used in mineral flotation ....  read more

Floating Larger Particles - Stage 1

This project is aimed at the development of methods and equipment for the recovery of coal particles by flotation, focussing on sizes up to 1 mm, with possible extension to a top size of 2 mm.

The project is based on the idea that the best way to process a flotation feed containing a ....  read more

Investigation into the Performance of Large Diameter Classifying Cyclones

Thisproject conducted an evaluation of the improvement in the sizeseparation step between 0.1 and 0.4mm, using a 1m diameter classifyingcyclone. This has potential advantages over traditional designs,in reduced capital and maintenance costs, simpler plant layout,and elimination of ....  read more

On-Line Vision Based Instrument to Measure Coal Flotation Froth Properties

Researchers have developed an on-line, vision-based prototype instrument to measure coal flotation froth properties.

Traditionally, optimal metallurgical performance in coal flotation circuits has been difficult to achieve due to the wide variety of ....  read more

Improved Measure of Ultimate Flotation Performance

This project was concerned with the development and validation of an improved laboratory flotation test designed to "fingerprint" the ultimate flotation performance that can be achieved for a particular coal feed. It is important to note that the aim was to measure a ....  read more

Potential for Reagent Consumption Reduction and Flotation Yield Enhancement Through In-Situ Picobubble Generation

Evidence is presented which illustrates that subjecting coal flotation feed to ultrasonic radiation can result in yield improvements of the order of 15%. The effect is most marked with coals containing large amounts of material in the - 0.05 mm size range. This type of size ....  read more

Evaluation of Residual Frother from Column Flotation Circuits

The major objectives of this project were to develop a technique for measurement of residual frother in plant streams and to determine the mechanisms by which residual frother is adsorbed and transported through the plant circuits.

The current trend in coal flotation is towards ....  read more

Development of Automatic Control Techniques for New Flotation Technologies

The primary objective of this project was to develop practical process control procedures to automate and optimise the new flotation technologies using currently available equipment.

This was achieved by fulfilling a series of secondary objectives, which included a study of ....  read more

Fine Coal Classification

This project formed part of a major program under the CMTE, with the overall objective of enhancing coal recovery by developing new or improved technology for fine coal  ....  read more

Turboflotation

Froth flotation is currently the most widely used method for fine particle processing but the capital and operating costs are high. This is mainly due to the use of the force of  ....  read more

Coal Flotation in a Centrifugal Machine

The aims of the project were:

• to develop a new type of flotation machine for the beneficiation of fine coal particles
• to test and demonstrate the machine by applying it to the flotation of coal in selected operating preparation plants

Coal Flotation Technical Review

In a simplistic view, the conerstone of the emerging new flotation technology is the fineness of air bubbles. In contrast with the mechanically agitated cells new technology may be termed collectively as 'microbubble flotation'.

Amongst the ....  read more

Cyclo-Flotation for Fine and Ultrafine Coal Cleaning

This project has established the potential of an advanced flotation process unit for cleaning fine and ultrafine coal, based on the superimposition of the centrifugal flow characteristics of the hydrocyclone on the flotation process. The sub-processes  ....  read more