Decanter Centrifuges

Solid Bowl and Screen Bowl Decanter Centrifuges. 

The two primary types of decanter centrifuge are : Solid bowl decanters and Screen bowl decanters.
For details and a video on how decanter centrifuges work please see our principle of operations page.

Used to process PVC slurry.Solid bowl decanter centrifuge.Manufactured in titanium. Casing top removed.600mm diameter decanter centrifuge.

  

 

 

 

 

The main features of the decanter centrifuge are:


For more information please see our BROCHURES and TECHNICAL INFORMATION sections.


Solid Bowl Decanter Centrifuges.

The commonest form of decanter is the bolid bowl decanter. It is used in to dewater slurries in many process applications including :

A large range of sizes, capacities and meterials of construction are available. See the size range table below for more information. Fume tight and pressure decanters are avaialbe for specialist and hazardous application.


Image750mm diameter pressure tight solid bowl decanter.

 

Screen Bowl Decanter Centrifuges. 

The screen bowl decanter centrifuge is operationally similar to the solid bowl units, but is designed to provide additional washing efficiency and enhanced moisture removal in applications where crystalline materials are involved. The screen bowl decanter operates in two stages, combining the clarification and sedimentation advantages of the solid bowl centrifuge and the de-watering benefits of an additional screen section. These centrifuges are typically used on BPA, some Minerals and Polyolefins.

ImageDecanter bowl with screen section.

 

 

 

 

 

The benefits of a screen bowl decanter include:


Decanter size range : Solid bowl and Screen bowl models.

Model :
150
225
450
550
600
750
900
1000
1200
1400
Diameter M
150
225
450
550
600
750
900
1,000
1,200
1,400
Length min M
300
700
700
1375
950
1875
1800
1500
2100
1800
Length max M
500
900
1,100
1,375
2,100
2,500
3,000
1,500
3,600
3,600
Typical Wt T
1.0
1.7
2.5
3
4.8
8
14
12
25
30
Motor min KW
5
11
15
30
30
55
60
75
110
110
Motor max KW
11
18
30
60
75
135
150
200
500
500
Types:
 
 
 
 
 
 
 
 
 
 
Solid bowl
ü
ü
ü
ü
ü
ü
ü
ü
ü
ü
Screen bowl
 
 
ü
ü
ü
ü
ü
 
ü
ü
Fume tight
ü
ü
 
ü
ü
ü
ü
ü
ü
ü
Pressure
 
 
 
 
ü
ü
ü
ü
ü
ü
Three phase
 
 
 
 
ü
ü
ü
 
 
 

Typical decanter bowl profiles.

Image

 

For more information please see our BROCHURES and TECHNICAL INFORMATION sections.

If you are considering laboratory or pilot testing to assess the performance that can be achieved with a decanter centrifuge please goto our Process Laboratory section for assistance and additional contact details.

Decanter centrifuges : Principles of operation.

The fundamental principle of a decanter centrifuge is accelerated sedimentation under gravity.

The sketch (a) below shows a simple settling tank with a continuously moving scraper removing the settled solids at the left hand end. The liquid flows over the top of the scraper blades and leaves the tank at the right hand end. According to Stoke's Law a solid particle within the tank will settle at a rate dependant on a variety of factors including the relative  density of the solids and the liquid, the size of the particle and the acceleration due to gravity.

Image

If the tank is transformed, as shown in (b), into a tapered cylinder (c) and the cylinder is then rotated at high speed about its centre line a high centrifugal 'G' force is produced on the liquid and solids. This centrifugal 'G' replaces the acceleration due to gravity in Stoke's Law and results in rapid sedimentation of those particles that are denser than the liquid. The continuously moving scraper in (a) is replaced by the helix shown in (c) which transports the solids out of the tapered end of the cylinder allowing continuous separation. The original settling tank (a) has now been transformed into a decanting centrifuge (c).

There are many variations of decanting centrifuges in use  in a wide variety of process applications; however the  basic principles outlined above apply to all types of  decanter centrifuge

Broadbent decanter centrifuge designs provide :

For more information please see our BROCHURES and TECHNICAL INFORMATION sections.