Spiral Concentrator
Multotec-designed spiral concentrators are used across the world in coal, gold, iron ore, mineral sands, platinum and chrome processing plants and other minerals.
As a turnkey supplier of gravity concentration equipment across the world, Multotec can deliver end-to-end spiral solutions, from process audits and test work, to complete spiral concentration plants optimised for your process. With our global branch network, we support your application with tailored field service and complete availability of spares for your plant.
We manufacture a wide range of spiral sizes and configurations that can be optimised to your application.
The benefits of the Multotec Spiral Concentrator:
- Beneficiate material between 38 and 2000 µm, depending on ore type
- Available in single, double and triple starts
- Spirals range between small diameter (+/- 560 mm) and large diameter (+/- 950 mm)
- 3 to 12 turn spirals as required by your application
- High separation efficiency reduces the number of stages on a plant, reducing overall footprint
- Sliding or auxiliary splitters can be used to achieve targeted grades and recoveries
- Auto Reject Channel® offers excellent removal of unsuitable particles
- Trough surfaces are sprayed with polyurethane to required thickness to improve the service life of the spirals
- Test work can be conducted for spiral concentrators to simulate client flowsheet
New Spirals
- Ultrafine chrome spiral
- Coarse (-3 mm) particle spiral
- Lowcut spiral (1.49) for coal application
- Large diameter cleaner and recleaner stage spiral
The Multotec Spiral Concentrators range:
Coal Spiral Concentrators
Single and double-stage spiral separators optimised for concentrating coal particles in the particle size 0.1 to 2 mm.
Mineral Spiral Concentrators
3, 5 and 12-turn spirals with various profile grades to separate high density particles in the particle size range 0.04 to 1.5 mm.
Spiral Test Units
Stand-alone, plug and play test units for heavy mineral and coal applications. Easily adapted to your process flow.
Gravity Slurry Feed Distributors
We supply a complete range of orifice and slot type slurry feed distributors for your spiral concentrator plant.
Launder Systems
We stock a complete range of launder systems for your gravity concentration plant, new or retrofit.
Spiral Accessories
We supply a complete range of feed distributors, feed boxes, launder systems, pipes, product boxes and splitters, and more.
Get in touch with your local mineral processing specialists.
Speak to our mineral processing division about your gravity concentration application.Contact us
We’ll help you lower your cost per ton targets
Our process engineers will work with you to optimise your spiral concentrator plant taking into consideration the feed grade and targeted product grade, recoveries and mass yields.
Whether for a greenfields plant, or optimisation or refurbishment of an existing plant, Multotec has the technologies and expertise to help ensure maximum gravity separation efficiency for your plant.
Spiral Separation services
Your local Multotec branch will help you with end-to-end solutions for your gravity concentration plant, from testing equipment through to field service, ongoing optimisation and any maintenance. We keep a wide range of spares and accessories for your spirals, reducing lead times to ensure maximum processing uptime.
Our gravity separation services include:
- Test work on spiral concentrators, laboratory and test plants
- Consultation on spirals, processes and your plant
- Commissioning of all spiral equipment
- Ongoing optimisation
- Design assistance to customers
Read more about Multotec field service offerings.
Spiral Separators for heavy minerals
Our gravity separators for heavy mineral applications, including iron ore, chrome, mineral sands and other high density minerals, separate particles in the size range 2 to 0.04 mm.
We have a range of spirals, from 3 to 12 turns, with high-, medium- and low-gradient profiles. Our high capacity spirals (the HX series) provide a per-start tonnage rating of 4 to 7.5 tons per hour, depending on the mineral type, and is especially suited for the treatment of low-grade ore, where large tonnages are processed.
Mineral spiral separator components include the spiral trough; sliding or auxiliary splitters; launders; distributor and piping; feed box; product box and stainless steel product splitters; and the discharge chute at the bottom of the modular housing frame. Our spiral separators have a diameter of +/- 950 mm.
Gravity Separators for coal
Our single- and double-stage spiral separators are optimised for coal particles in the size range of 1 to 0.1 mm, providing enhanced coal washing for slurries. Their compact, modular design provides flexibility when building or upgrading your plant.
Double start spirals reduce the requirements of height and floor space in a plant, and reduce capital and operating costs. The MX7 spiral separator is ideal for difficult-to-wash coals, improving the overall efficiency of tougher separation applications.
These gravity concentrators are precisely designed and built from high-quality materials that provide a long service life, lower costs of operation and low maintenance.
The science behind the spiral
Spiral concentrators are simple low energy-consuming devices used for mineral separation mainly on the basis of density or by shape. Spirals are widely used in mineral processing as a method for pre-concentration and have proven to be metallurgically efficient and cost-effective.
As the mineral stream is fed from the top of the spiral, a combination of forces act on particles as they move down the trough of the spiral circuit. These forces include gravitational forces, centrifugal force, hydrodynamic drag, and lift and friction forces. Apart from the forces acting on a spiral, the properties of the slurry flowing on a spiral including, solids concentration, feed rate and wash water also plays an important role in the separation on the spiral.
During separation, the heavy particles migrate toward the inner region of the trough, with lighter-density particles migrating to the outer edge of the trough. In a dry spiral separation, materials are sorted by shape. Rounder particles travel faster, are forced to the perimeter of the spiral, from where they can be collected separately from non-round material.
With over 45 years’ experience in mineral processing applications across the world, Multotec is a leading supplier of gravity concentration solutions that optimise your plant performance.
