PBS decanter centrifuges can be used for a wide range of applications: from separation of municipal and industrial sludge, through food and chemical industries up to agriculture. Based on specific requirements for separation of solid and suspended particles from liquids, 4 models of decanter centrifuges are offered, which can be also connected in parallel.

Overview of technical parameters

Type DO250 DO250 twin-engined* DO301 DO520
Screw diameter (mm) 250 250 300 500
Motor (kW) 12 2x 11 1x 18.5 and 1x 5.5 1x 33 and 1x 7.5
Operating energy consumption (kW) 7 8,5 13 19
Maximum speed (rpm) 4100 4100 4000 2800
Weight (kg) 910 1010 926 2240
Flow rate (m3/hour) 1 - 4 1 - 4 2 - 6 10 - 15
Number of equivalent residents 2 500 - 12 000 2 500 - 12 000 10 000 - 20 000 15 000 - 50 000
Dimensions LxWxH (mm) 2375 x 600 x 870 2500 x 830 x 1000 2437 x 767 x 636 3366 x 1048 x 956

* This centrifuge is used in the mobile decanter MODO250

Technical description

Main parts of the centrifuge are two coaxial, conical/cylindrical bowls having the same sense of rotation but different speeds. On the inner bowl a screw is welded. The outer bowl is screenless.
Both the bowls are supported by rolling bearings in bearing pedestals, which are mounted on a base frame welded from rolled sections.
Both the bowls are driven by an electric motor via a special gearbox providing different speeds of the bowls or by three-phase motors for the bowl and the screw controlled by frequency converters. Rotating components of the centrifuge are protected by guards during operation. The device includes a switchboard where control and protection elements are located. 

Description of decanter centrifuge function

Sludge enters the rotating bowl of the centrifuge through a fixed feed tube. By the effect of centrifugal force it is forced onto the jacket of the outer bowl, where particles of higher density are separated and settle on the wall of the bowl. Thanks to the differential speed between the screw and the outer bowl, these particles are transported by the screw to the conical part of the outer bowl, where there are lifted above the liquid level and dewatered by effect of centrifugal force.  Dewatered sediment is delivered by the screw to the discharge holes, through which it falls into the hopper, and further into the space under the centrifuge, from where it is transported by an appropriate equipment to stated place. The clarified liquid (filtrate) flows through the control caps in the end of the bowl into a collector. The collector is usually connected to a piping system.