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Hydrocyclones, otherwise referred to as cyclones, are mechanical separation devices that utilize centripetal or centrifugal forces within a vortex in order to sort particles present within a liquid suspension.
Closely related to the centrifuge device, whose separation force is achievable by rotation of the entire equipment, the hydrocyclone instead depends upon the movement of the centrifugal forces within the fluids to allow for adequate particle separation1. In 1891, E. Bretney patented the first hydrocyclone, and from this time through 1948, a large number of patents continued to be granted on this technology.
In 1939, Dutch State Mines (DSM) was the first company that utilized hydrocyclone technology as a means of both cleaning coal and dewatering sand2. Since its introduction into the marketplace, hydrocyclones continue to be used today as a means of dewatering sand, however, its applications have stretched to other industries including industrial minerals, hard rock mining, aggregates, coal and many more. With their simple design and complete lack of moving parts, hydrocyclone technology offers industries a relatively inexpensive way to separate materials safely and simply to accommodate their needs.
To achieve adequate particle separation, the liquid mixture is injected into the hydrocyclone, thereby creating a vortex that is dependent upon the specific densities of the material to send materials outward at a rate determined by decreasing levels of coarseness.
Hydrocyclones are equipped with two different exits, in which the underflow that is present at the bottom of the device is responsible for releasing the coarser fraction of particles, whereas the overflow present at the top of the device will contain the lighter, or finer, fraction of materials1. While hydrocyclones can be made up of metal, specifically steel, ceramic or plastic material, the amount of durability, specifically the heat or pressure that will be applied to the system, as well as any chance of abrasion, are factors that help industrial workers determine the type of hydrocyclone that is most appropriate for their needs.
To allow for the successful operation of the hydrocyclone, the geometry of the cyclone, which describes the shape and area of the inlet, as well as the specific characteristics of the feed stream entering the cyclone are important determining factors.
For example, in situations where oil is separated from water by use of hydrocyclone technology, the main feed characteristics are based on the concentration, size, distribution and density of the oil droplets, the density of the water, as well as the temperature and overall viscosity of the mixed sample.
Since 1978, Minco Tech Australia has been a leading Designer and Supplier of hydrocyclones for mineral processing industries across Australia.
With a specific dedication towards continuing the research and development of cyclone technology on a global level, Minco Tech offers a number of different design parameters for their cyclone technology that allow for its optimization for specific projects that involve diamonds, coal, gold and nickel3.
Similarly, McLanahan Corporation offers customers a variety of hydrocyclone devices to address their specific industrial need. The McLanahan SeparatorTM, for example, is the first ever vacuum-assisted hydrocyclone, whose unique geometry allows this product to be a standard for stock piling and inter-stage processing needs4.
The SeparatorTM is equipped with a rubber underflow regulator, as well as an overflow pipe that is fitted with an air valve to gently regulate and blend air into the generated siphon, thereby allowing for consistent underflow density to emerge regardless of the density of the applied feed.
Metso, a 150 year old industrial company that offers a number of products used for mining, recycling, oil, gas and paper purposes, has recently introduced their newest hydrocyclone technology known as the MHCTM Series. Referred to as the next generation of hydrocyclones, the MHCTM Series allows for a sharp particle with a significantly reduced potential to accumulate linear wear5.
With applications available for a full range of mineral types, the MHCTM Series device is also equipped with a precise new design for the inlet to allow for a remarkable increase in its potential unit capacity.
References and Further Reading
- “Hydrocyclone” – Revolvy
- “History of Hydrocyclones Development” – New Technologies
- “Hydrocyclones” – Minco Tech Australia
“Hydrocyclones & SeparatorsTM” – McLanahan
- “The MHCTM Series patent-pending design represents the next generation of hydrocyclones” – Metso