Spiral concentrators, also known as spiral separators, separate ore and the desired mineral or material that is being mined in a specific operation. Spiral concentrators are used in the beneficiation process in mineral processing plants.
Mineral beneficiation refers to the process of extracting economically essential minerals from the ore. This process falls within the mineral processing operation, which refers to the complete cycle of operation from beginning, to end. Spiral concentrators are typically used in coal, gold, iron ore, mineral sands, platinum and chrome processing applications.
Below is an iron ore flowsheet to illustrate where spiral concentration occurs in the mining process of minerals. Spiral concentration is located at the bottom left of the diagram, which only comes into play after crushing, sampling, desliming, and screening processes are completed. Download the flowsheet here.
Disclaimer: All Multotec equipment is shown in green. Variations of this block flow sheet will exist based on the mineralogy of the ore. This flowsheet and its content are the copyright of Multotec (Pty) Ltd.
Spiral concentrators play an important role in the beneficiation process. Shorten operation timelines with effective and efficient spiral concentrators from Multotec Canada!
Equipment other than spirals which can be used in the beneficiation process includes cyclones, magnetic separators, and classifiers. Multotec Canada can help you identify which equipment would be the most effective and efficient for your specific application.
Multotec Canada manufactures over 10 different types of spiral separators, offering a range of shapes, diameters, heights, starts, wash water systems, and throughput capacities in order for our clients to meet their requirements in the best way possible. View our spiral concentrator range.
A spiral concentrator, which resembles a large screw-like structure, incorporates a vertical spiral channel with an inner and outer wall. Mineral feed slurry is then introduced at the top of the spiral, the gravity concentration equipment then makes use of centrifugal force to separate materials based on their densities.
Density is related to how much mass is packed in a specific volume. For example, a block of gold has a high density as it holds a high volume of mass in a small volume. A balloon, on the other hand, that is filled with air has a low density, due to its small amount of mass in its volume.
A spiral concentrator makes use of gravitational force to separate the minerals and ore, which is dependent on the volume of mass in the material, therefore density, as explained above. For instance, dropping a block of gold will have a greater gravitational force in comparison to dropping an air-filled balloon from the same height.
Centrifugal force, which alters the direction of gravitational force, therefore pulls the heavier material towards the centre of the spiral, causing the lighter pieces of material to be forced towards the outer edge of the spiral. Gravitational force groups materials based on their masses, separating the types of material from each other. The separation of materials enables easy extraction of valuable minerals.
Different applications, however, will have different requirements. For example, coal will be the only material where the lighter material is needed or desired, other applications such as iron will require the heavier material in the separation of materials. We can meet the needs of your unique application!
Using a highly efficient spiral concentrator reduces the number of stages in a plant, reducing timelines and overall footprint. This is because mineral plants can improve their recovery rates and the removal of undesired gangue materials, all through the use of gravitational forces in spirals.
Fun Fact: Canada is the globe’s leading producer of potash and is ranked in the top five producers of aluminium, cobalt, diamonds, fluorspar, gemstones, gold, indium, niobium, palladium, platinum, tellurium, titanium concentrate and uranium.
Click on the links to get access to Multotec Canada’s mineral flow sheets for Canada’s top-mined minerals!
Multotec Canada is committed to finding new solutions to new problems across all scales. New research and development have shown that our compact, modular designs add flexibility when building or replacing spiral plants, with the distinct advantage of extending the life of your plant while reducing overall maintenance costs.
Get rid of the bulk of ore so you can shorten timelines and focus on getting the most purity in your Canadian mineral processing plant! Watch this short video on how our gravity concentration equipment can be optimised by Multotec Canada to achieve the client’s requirements, which include higher recovery rates.
Watch this video for practical examples of how Multotec can optimise your spiral separator circuits to deliver better results.
With over 50 years of experience, Multotec has become the leading supplier of gravity concentration technology solutions which aim to reduce the operating costs of mineral processing plants. Multotec Canada delivers end-to-end spiral separator solutions, from consultations, design assistance, process audits and test work, and complete spiral concentration plant optimisation, to equipment (including accessories and spares).
Multotec’s global footprint of process engineers and specialists helps you lower your cost per ton through optimised processes that are effective and efficient. Our equipment is ideal for gold, nickel, copper, coal, chrome, mineral sands, platinum, iron ore and diamond processing and beneficiation plants: accommodating popular mines in Canada!
Water is used in the spiral separators to increase fluidity, reducing the beating . Wash water is also used to address silicate challenges which make it difficult for material separation.
This is because the silicates, which refer to a particle size above 300 microns, behave like heavy material, causing it to gravitate to the centre column, where you should only have clean iron ore, therefore contaminating the stream.
Multotec Canada’s spiral separators are available in different types of wash water systems, mainly high-flow systems, and drip systems. The high-flow system handles a large volume of water, where the drip system, a Multotec-designed spiral, maximises the retention rate of water by using minimal water, therefore reducing the process’s footprint and operation costs.
Yes, our spiral concentrators can be used for dry separation. In a dry separation process, materials will be sorted by shape. Rounder particles, which travel faster, are forced to the perimeter of the spiral, enabling users to collect round particles separately from non-round material.
Factors that influence the efficiency of spiral concentrators include the flow of slurry, the concentration of solids, feed rate, and wash water. A mining spiral can additionally be paired with other technologies to enhance the grid and improve the recovery of the overall circuit.
There should be at least 1.0 SG difference in the materials being separated for good separation (mainly ranging from 20–40% solids), depending on the characteristics of the mineral being processed. The shape of the materials being separated could be optimised earlier in the mineral process.
Multotec Canada specialises in plant optimisation that helps you achieve your plants’ requirements faster and more efficiently where possible, to reduce your operational costs and improve your profitability.