Solid bowl centrifuge FAQs
What is a solid bowl centrifuge?
A solid bowl centrifuge is a style of mineral processing centrifuge that is used in the mining industry for separation of solids and liquids. A centrifuge is employed to separate a slurry that consists of two substances with different densities by using the force resulting from continuous rotation. Solid bowl centrifuge technology can be used for cost effective solid-liquid separation in applications such as tailings dewatering and fine coal recovery.
Solid Bowl Centrifuge - Animation
How does a solid bowl centrifuge work?
The solid bowl centrifuge (SBC) consists of a horizontal centrifuge rotor with a scroll conveyor inside it which together is referred to as the rotating assembly. The assembly rotates spins around its own axis at high speed thereby generating high centrifugal force that enables separation of solids from the liquid. The slurry enters the rotor through a stationary feed tube. The separated solids are scrolled out by the conveyor in the form of a dry solids cake whereas the clear liquid (centrate) overflows the weir plates from the opposite end.
What are the benefits of solid bowl centrifuges for mine sites?
With the latest solid bowl centrifuges, mining companies see a reduction in water usage by up to 90%, as they are able to extract and re-use the process water. They are also able to dispose of the dry tailings in a similar fashion to overburden and together with coarse rejects. This increases operational efficiencies and helps companies meet sustainability targets. In many cases, dry disposal alleviates the risky and expensive practice of storing slurries in a tailings dam. Other mining companies gain additional capacity as existing TSFs are reaching capacity and new licenses are harder to come by.
Watch the webinar recording on the right on-demand to learn about the benefits of solid bowl centrifuges for tailings dewatering application in various mineral processes >>>
Today’s solid bowl centrifuges have ten times the capacity of older models, with Alfa Laval investing significantly R&D resources to engineer today’s high performance SBCs such as the Alfa Laval P3 which is fully automated requiring minimal operator intervention to meet varying feeds, has high wear protection and increased reliability.
How does solid bowl centrifuge compare to a belt-press?
The belt press achieves filtration by passing a pair of filtering cloths and belts through a system of rollers and the tailings solids are sandwiched between the two filtering cloths. It has low energy requirement and is simple to operate. However, it has a considerably large footprint and requires frequent maintenance and cleaning. For effective dewatering of tailings with fairly high clay content the belt press requires large amounts of flocculants and in combination with the large quantities of wash water required to keep the filtering cloths clean, the belt press has a very high OPEX. Since it has a limited throughput capacity (a 3m x 3m belt press can dewater 20-25 t/h solids on dry basis) the number of units needed for tailings dewatering is high resulting in high CAPEX.
Whereas, although the SBC technology has existed for several decades it is only in the past 8-10 years that design improvements made by Alfa Laval in wear protection of key components coupled with changes in its geometry and operating philosophy have enabled the SBC to be utilized to deliver high solids cake concentration, even at high flow rates. It does require moderate dosage of flocculants in some tailings dewatering applications but has the highest unit capacity per footprint. Thus the modern SBC has a relatively lower CAPEX and the OPEX is also attractive on account of its high throughput and lower lifecycle costs.
From the coal face
How to manage tailings storage facilities (TSF) is an ongoing challenge for Australia’s mining and minerals industry, from a risk mitigation and cost point of view. Alfa Laval Australia Mining Engineer, Hamid Foroush, explains how solid bowl centrifuge technology has evolved over time to provide an economically and technologically superior solution to dewater tailings and recover process water.
P3 Product details
Alfa Laval P3 solid bowl centrifuges are specifically designed to separate mining and mineral slurries, tailings and sludge into a solid phase and liquid phases. Find out more about P3 centrifuge!
Base minerals and mining
Alfa Laval has a range of equipment and the know how to help you optimise key processes in base mineral beneficiation and extraction applications.
Why Alfa Laval
A reliable partner for the Mining and Mineral Processing Industry
Alfa Laval offers customers not only solid bowl centrifuges with very large capacity (up to 80 dry tonnes per hour) specifically designed for heavy duties in mining and mineral processing. The company prides itself of a strong local heritage of over 90 years in Australia with a significant local service and support presence including a fully equipped Service Centre in Sydney and field engineers based around Australia to visit even the most remote mining sites.
Swedish headquartered Alfa Laval is a leading global manufacturer offering its expertise, products, and service to a wide range of industries in some 100 countries. The company is committed to optimizing processes, creating responsible growth, and driving progress – always going the extra mile to support customers in achieving their business goals and sustainability targets. Alfa Laval has 17,500 employees. Annual sales in 2019 were SEK 46.5 billion (approx. EUR 4.4 billion). The company is listed on Nasdaq OMX.
Alfa Laval’s innovative technologies are dedicated to purifying, refining, and reusing materials, promoting more responsible use of natural resources. They contribute to improved energy efficiency and heat recovery, better water treatment, and reduced emissions. Thereby, Alfa Laval is not only accelerating success for its customers, but also for people and the planet. Making the world better, every day. It’s all about Advancing better™.