30 years ago decanter centrifuge was considered high tech equipment due the challenge to cast high strength rotating bowl and control of erosion from high abrasion solids. At that time decanter centrifuge could cost up to 1 million US dollars. Any enterprises which manufactured decanter centrifuge were considered high tech company.
With advancement of technology, there is no longer mysteries in decanter centrifuge, and many people take them as granted. However one need to have at least some basic knowledge about decanter centrifuge before he can understand and operate them in a proper and safe manner.
Let us have a look at rotating bowl.
First there is an inlet tube, which dumps slurry into the rotating bowl. Please note, the material inside the rotating bowl is spinning at very high speed with the rotating bowl. Once slurry from inlet tube drops down to the wall of rotating bowl. On one side the slurry will produce erosion to bowl wall, and it also damage solids settlement on bowl wall. A properly designed decanter centrifuge can minimize this disturbing effect.
Second component is screw conveyor. This device plays instrumental role for the performance of decanter centrifuge. The more effective the screw conveyor is, the more efficient the decanter centrifuge is. Therefore it is very important to have proper design of screw conveyor. Extensive industrial experience about the pitch, angle and differential speed are the foundations for successful design of screw conveyor.
Third consideration of solids discharge section. The biggest challenge here is erosion, as there is huge centrifugal force on the solids. Depending on the feature of solids, they can be very dry like powder, or they can be like paste, sticky and viscous. Discharge ports withstand tremendous erosion and all measures should be taken to protect discharge portion to maximize their service life.