Situations in Which You Would Require a Hydrocyclone
Hydrocyclones are devices used to separate particles or molecules suspended in liquids based on their size, shape and density using centrifugal force. They’re widely used in industries like mining, quarrying, food and beverage, recycling, wastewater treatment, and oil and gas to classify, separate or dewater materials efficiently without the need for moving parts or complex machinery.
Hydrocyclones are particularly suited to wastewater treatment because they’re ideal for separating solids from liquids without the use of chemicals or filters that to block easily. They are often used as a pre-treatment to optimise final sanitisation in clean water supply applications, or to remove contaminants in waste water to protect the environment. As the size and design of hydrocyclones can be altered in so many ways, they’re also useful devices for many different applications involving separation of fluid mixtures.
How Do Hydrocyclones Work?
A hydrocyclone is made up of a conical-shaped body with one inlet and two outlets – one for heavier, denser materials and one for light materials. Slurry enters the hydrocyclone through the inlet at high velocity at a tangent to create a spinning motion. An air inlet in the base draws a vortex of air up through the central core that forms. Denser particles move out towards the edge via centrifugal force, sink to the bottom and exit through the lower outlet. Lighter particles and water move upwards and out through the high outlet.
When Would You Employ a Hydrocylcone?
Here are some common examples where hydrocylone use is beneficial:
- Sand and fine grit removal – Hydrocyclones are an excellent option for removing grit and fine solids (<200 microns) from wastewater before secondary treatment. By removing heavy, non-organic solids from water as it enters the facility (the headworks), subsequent treatment of the remaining lighter, bio-solids is more efficient. Hydrocyclones are configured to “cut” a particular size and mass of particle, known as the “d50”. While most of the particles sink and exit at the bottom, particles finer than the “cut point” will tend to rise and exit with the water. The result is clearer water and ‘thickened’ slurry, making both easier to further refine and process.
- Protecting your equipment – A hydrocyclone is a cost-effective addition when you want to protect your downstream equipment from abrasive particles and heavier solids in wastewater. By removing these particles early on, it reduces blockages, and wear and tear on pumps etc.
- Ensuring water quality – Maintaining water quality is important not just for public health but for the environment too. Using a hydrocyclone to remove grit and sand enables other treatments such as sanitisation, flotation, flocculation, settlement clarification, and bio treatments to work effectively. During dredging or construction site dewatering, they can keep returned water clarity where it should be and streamline operations at volume, as they’re designed to operate continuously
- Pre and post-treatment processes – A hydrocyclone can help reduce the accumulation of impurities on filter surface membranes. Deciding where this occurs – pre-, mid- or post-process – depends on whether you want to produce high dry matter (remove more water, potentially with more fines content), or retain the maximum amount of solid fines (such as precious metals extraction). Hydrocyclones are also good for pre-screening coarser particles before the water flows through a finer membrane to stop it blocking up or for fine particle removal post-sieving/screening.
- Wastewater and industrial wastewater treatment – They’re ideal for removing solids from sewage before it is sent for treatment. They can also separate suspended solids from industrial wastewater ensuring only high clarity water is discharged into the environment.
- Mineral processing – A hydrocyclone is adept at separating valuable minerals from ores and tailings.
Benefits of Hydrocyclones
One of the main advantages of hydrocyclones is the lack of moving parts which means lower maintenance and costs. Separation quality is maintained by keeping the pump feed pressure and flow rate correct. Similarly, their compact and simple design means they’re ideal for scenarios where space is at a premium such as in mines.
Unlike using large settlement tanks that require a long retention time, hydrocyclones can process high flow volumes, saving time and space.
They’re highly efficient at separating materials ranging in different densities and sizes and because of this attribute, combined with the ability to handle different flow rates, they’re scalable too.
Hydrocyclones are versatile, cost-effective tools, ultimately designed to improve operational efficiencies across a range of industries. By using centrifugal force for separation, they provide a reliable way for separating challenging mixed fluids and suspended solids.
Wondering if a hydrocyclone could benefit your process and lower your costs? Check out our range of hydrocyclones and speak to our hydro-process experts for application-specific advice.
