Centrifuge Repair, Centrifuge Rental, Centrifuge Sales, Centrifuge Parts, Used Centrifuges, Centrifugal Liquid Solid Separation Alternatives

• What Is The Liquid / Solid Separation Process?
• How Does a Centrifuge Work?
• What is the Centrifuge Process?
• How Do I Choose A Centrifuge?
• How Do I Know What Type Of Centrifuge To Choose?
• What Are The Applications For A Centrifuge?
• What Are The Advantages Of Using A Centrifuge Over Other Methods?

What Is The Liquid / Solid Separation Process?

There are three basic processes used for the separation of suspended solids from a liquid media:

• Sedimentation
• Filtration
• Centrifugation

Sedimentation allows solid particles, which are heavier than the liquid media, to separate and sink to the bottom of a container under the influence of gravity.

Filtration incorporates the use of a filter media by virtue of its degree of porosity and regulates what may pass through it. Since the filter media collects suspended solids, the material progressively builds up and will eventually impair performance and require removal, cleaning, and / or replacement.

Multiply the power of gravitational force by more than 2,000 times.

Centrifugation is a highly accelerated form of sedimentation. This rapid form of sedimentation is attained by introducing centrifugal force to the liquid / solid media generating a force that can be over 2.000 times more powerful than gravity itself. This method is fast and eliminates the need for filter media. US Centrifuge Systems's complete range of liquid / solid separating centrifuges are designed to separate suspended solids heavier than the liquid media without the use of consumable filter media.

How Does A Centrifuge Work?

A centrifuge works by spinning a vessel containing the material to be separated at high speed. It is very much like the rides at the fairground that rotate. You have to lean towards the center to overcome the force caused by the rotation. In fact, some rides are designed specifically to press your body against a back support. The centrifuge spins at very high speeds and pushes the 'heavy phase', usually the solids, to the outside of the vessel, just as you would see in the clear flask standing on the bench top.

What Is The Centrifuge Process?

If you take a sample of the liquid / solid mixture in a clear flask and you observe that there is a separation of the two phases with time, the separation is caused by the force of gravity. The centrifuge process speeds up the process by increasing the force of gravity 1000 to 4000 times, depending on the equipment. The result is that a process that can take 1-12 hours in a flask is achieved in seconds using centrifugation.

How Do I Choose a Centrifuge?

Because there are such a variety of both standard and unique applications, choosing the correct centrifuge is often more of an art than an exact science. Determining the correct machine style and model size requires a thorough understanding of the application and very often sample testing. The more a customer knows about their process and the results desired, the more helpful it is. And when a customer calls or e-mails, we would initially focus on determining the following:

• Description of the liquid phase and the solid phase
• Total liquid volume of the system and amount of available process time and / or required process flow rate
• Quality of required liquid phase / phases - targeted concentration of impurities
• Amount of solids that need to be removed from the given liquid volume
• Targeted dryness of the solids
• What the customer wants to achieve

From this simple calculation we can often quickly determine which style of liquid / solid separation is most applicable for the application. A further simple lab centrifuge test determines the most appropriate type of centrifuge, whether it fits the customers thinking, and if it is within the expected customer budget.

How Do I Know What Type Of Centrifuge To Choose?

Once you have seen that we can separate the solids and the liquid using centrifugal force, you can rely on our expertise to guide you. A lot depends on the volume and type of solids that are produced by the separation and the 'G' force required to make that separation. Our range of equipment includes continuous and automated batch centrifuges and we will help you select the most cost effective installation to achieve your desired result.

What Are The Applications For A Centrifuge?

In general:

• Separation of solids that are heavier than the liquid and settle with time
• Classifications of solids of different size in a slurry
• Separation of immiscible liquids that have different densities

These general concepts are applied to specific process requirements:

• Dewatering of a solid
• Clarification of a liquid
• Recovery of a product
• Thickening of a slurry
• Classification of a slurry
• Purification
• Concentration

You will find these duties in all industries and in the wastewater treatment from all industries. It is a simple process to determine the effect and cost of centrifugation.

What Are The Advantages Of Using A Centrifuge Over Other Methods?

Depending on the nature of the application, centrifuges often offer numerous advantages over traditional methods of solids dewatering and liquid filtration / fluid clarification.

• No consumable filter media or pre-coat is required
• Chemical addition is not always a requirement
• Will not blind-off or clog-up
• Maintains full system flow rates
• Automatic continuous and semi batch self-cleaning centrifuges available
• No human contact with the waste material, which can be discharged directly into a waste drum, hopper, bin, or roll-off container
• Separates suspended down to 2-micron in size
• Centrifuge generate a relatively moisture free cake for disposal or reclaiming
• Centrifuges are effective on low solid volume applications

Common centrifuge alternatives include:

• Filter Press
• Belt Filter Press
• Bag Filter
• Membrane Filter

The centrifuge is often considered an effective alternative to the filter press and is desirable because the centrifuge features an automated self-cleaning cycle that does not require constant labor and maintenance to maintain operation.

The centrifuge is often considered as a more economical and effective alternative to the belt filter press and is desirable because the centrifuge is often less expensive to purchase when through put capacities are compared, the centrifuge requires less labor and maintenance, and unlike a belt filter press the centrifuge can provide suitable results without polymer addition in some applications.

Although typically more expensive, the centrifuge is often considered as an effective alternative to bag filter systems and is desirable because the centrifuge does not require consumable filter bags nor does it require the manual handling of sloppy wet filter bags. Plus the centrifuge will not blind-off when filtering gelatinous materials from the liquid media. With an automated self-cleaning centrifuge the separated sludge cake is discharged directly into a waste drum or hopper for disposal and requires no direct human contact with the sludge.

The centrifuge is often not considered as an effective alternative to membrane filtration but rather a helpful addition as a pre-filter. By centrifuging the liquid media and separating a large percentage of the small particles, fouling of the membrane is reduced and a higher membrane flux rate can be maintained over a longer period of time. The centrifuge can even be applied to the membrane concentrate.