Alfa Laval decanter centrifuges provide exceptional performance when separating solids from 1 or 2 liquid phases in one single continuous process. The units are designed to handle a wide range of particles with diameters from 5 mm to a few microns. With their high efficiency, continuous operation, low capital cost/capacity ratio, low maintenance costs and low energy consumption, the decanter centrifuges are ideal to use in a range of duties including process, food and waste applications.
Make a difference to your business and the environment
- High-performance separation, resulting in high-value products and low waste management costs
- Low energy consumption and carbon footprints
- Low maintenance costs thanks to high-grade machine materials
- Low capital cost/capacity ratio
What is a decanter centrifuge
In essence, a centrifuge is a settling tank whose base is wrapped around a centre line. Rotating this entire unit rapidly means that the effect of gravity is replaced by a controllable centrifugal force that can have an effect up to 10,000 times greater.
This force is then used to separate liquids from other liquids and solids efficiently and with great accuracy, and in a manner that is easy to control.
There are several different basic types of centrifuge normally used in industrial separation. Decanter centrifuges are generally used for greater solids concentrations with larger particle sizes. Disc stack separators, on the other hand, are ideal for a wide range of separation tasks that involve lower solids concentrations and smaller particle and droplet sizes.
Choose decanter according to your industry/application
Oil & Gas decanters
Palm oil decanters
How does a decanter centrifuge work?
What happens during solid-liquid separation using our decanter centrifuge? Subject to centrifugal forces, the denser solid particles are pressed outwards against a rotating bowl wall, while the less dense liquid phase forms a concentric inner layer in a decanter centrifuge. Different dam plates are used to vary the depth of the liquid – the so-called pond – as required. The sediment formed by the solid particles is continuously removed by the screw conveyor, which rotates at a different speed than the bowl. As a result, the solids are gradually “ploughed” out of the pond and up the conical “beach”.
The centrifugal force compacts the solids and expels the surplus liquid. The dried solids then discharge from the bowl. The clarified liquid phase or phases overflow the dam plates situated at the opposite end of the bowl. Baffles within the centrifuge casing direct the separated phases into the correct flow path and prevent any risk of cross-contamination.
The speed of the screw conveyor may be automatically adjusted by use of the variable frequency drive (VFD) in order to adjust to variation in the solids load.
When to use decanter centrifuges
Separating solids from liquids plays a key role in countless industrial processes. Traditionally, many businesses use a clarifier or settling tank, in which particles, sediment and solids gradually fall to the bottom due to the force of gravity. However, such clarification is an extremely slow process with not so controllable results.
To accelerating the process, decanter centrifuge operation makes use of centrifugal force – the effect can be up to 4,000 times greater compared to using gravitational forces. Solid-liquid separation can also be easily controlled by adjusting the speed of rotation.
Why Alfa Laval?
Global industry leader
Founded in 1883, Alfa Laval has led the way in centrifugal separation technology with continuous breakthroughs, and our high-performance decanter centrifuge is one of them. We have had practical experience with the design and manufacture of decanter centrifuges since the 50s. Today, with facilities all over the world, Alfa Laval is in a position to provide customers with superior products, superior service and superior results at any location.
Advanced material and technology
Alfa Laval uses high-grade stainless steel for all parts that come into contact with the process, in order to avoid any risk of the corrosion associated with the use of carbon steel.
Rotating components of Alfa Laval decanter centrifuges exposed to high stress are machined from high-strength centrifugally cast stainless steel. This ensures castings with a uniform grain structure free from flaws and defects as well as a completely weld-free finished component. The results are maximum strength, unparalleled reliability and a long service life.
All wear-prone areas of Alfa Laval centrifuges – the feed zone, solids discharge output zone, bowl and scroll – are protected by abrasion resistant material, selected to match the pattern of wear in each particular industrial process.
Continual refinement of the seal technology used in Alfa Laval decanter centrifuges is ensured by our technological resources. This is an area where Alfa Laval expertise and experience also make a key difference.
Alfa Laval has full control over the entire supply chain, which means that we can provide customers with response times, availability and lead times that are second to none.
Our worldwide service capabilities and vast experience with the contract maintenance and service of decanter centrifuges ensure that any service work required involves the absolute minimum of disturbance to operations.
For customized service solutions, our performance agreement can be tailored to your specific needs, with the aim to maximize your performance and reduce your operating costs.
Australia's largest centrifuge service centre
Alfa Laval's major service centre in Huntingwood, NSW offers major refurbishment of centrifuges, dynamic balancing of centrifuge bowls, centrifuge conveyor repairs & balancing, gearbox repairs & servicing, assembly, spare parts warehousing and many more specialist services by highly skilled engineers and technicians. Alfa Laval also has minor service centres in WA and QLD as well as a large team of field service engineers around Australia for onsite support and repairs.