Definition of Screw Decanter Centrifuge
The screw decanter centrifuge is a kind of continuous and efficient separation equipment. It uses centrifugal force to separate different density media and is ideal for the separation of liquid with solid phases, and liquid phases with different specific gravity.
SeFluid’s SELW series are widely applied to concentrate, dewater and classify the suspension of solid particles. In particle size, the range is a few microns to a few millimeters. In industries, for example, chemical, pharmaceutical sewage treatment, printing and dyeing, screw decanter centrifuge is necessary.

specifica
Energia
11-37 kw
Capacità
0.5-40 m³/h
Velocità
2700-4800 rpm
Separation Factor
2100-3000
Principle of Screw Decanter Centrifuge

A screw decanter centrifuge is gradually accelerated by the frequency converter. The main and auxiliary pulley drives the machine. After that, the drum and the input shaft of the differential reaches the rated speed. Due to the action of the differential, the spiral generates a stable differential speed ahead of the drum to achieve the spiral discharge function.
When the speed becomes stable, the suspension enters the centrifuge from the high tank or feed pump. Then it is accelerated by the spiral accelerator bucket and flows via valve and feeding pipe into the drum. Under the strong centrifugal force, the solid phase particles are thrown on the settling wall. Subsequently, the particles deposit on the inner wall of the drum. Pushed by a spiral, the slag is continuously pushed to the small end of the drum. Finally, it is discharged through the solid phase collector shell from the slag outlet.
The separated liquid is further clarified by the separating vanes. Subsequently it is discharged through the overflow holes of the drum and the liquid-phase collection hood. During the entire separation process, the suspension is continuously fed. Meanwhile, the clarified liquid and slag is continuously discharged to get continuous automatic separation.
Features of Laboratory Bead Mill
1
Low moisture content of the slag.
2
Large L/D ratio (up to 4.4).
3
Small differential speed system.
4
Low noise: noise level below 65dB(A).
5
Small power consumption, energy saving, low maintenance cost.
6
With precision dynamic part and working speed balancing for smooth running.
7
High separation factor and large processing capacity.
8
Continuous processing with high automation.
R/D Ratio, Rotation Speed and Differential Speed System of Screw Decanter Centrifuge
Firstly, large L/D ratio increase the material clarification and dewatering residence time. Secondly, high rotational speed with large centrifugal force and small differential speed can reduce screw stirring of materials. These will increase dewatering residence time. As a result, these features will improve the separation effect of sludge thickening, dewatering and clarification. Compared with conventional screw decanter centrifuge, the solids and slag are drier and the separation liquid is more clarified.
Key Parts of Screw Decanter Centrifuge
Drum
Made of stainless steel, column conical structure, symmetrical distribution of adjustable liquid stopper plate; solid-phase outlet sprayed with wear-resistant alloy powder.
Spiral
Made of stainless steel material, equal pitch design, special treatment on the surface of the cylinder body, solid, wear-resistant and anti-corrosion.
Differentials
Cycloid differentials, planetary gear differentials, hydraulic motor differentials.
Motor
High quality motor is applied for our screw decanter centrifuge series.

Applications of Screw Decanter Centrifuge
1
Dewatering of oilfield drilling and mining mud.
2
Meat, vegetable processing (oil, fat, starch, soy protein).
3
Liquor and fruit juice production (wine, beer, vegetable juice, juice).
4
Sludge thickening and dewatering in urban sewage treatment plants, municipalities, water supply plants, industrial water and wastewater treatment plants.
5
Sludge dewatering in chemical, woolen, printing and dyeing, electroplating, tanning, paper making and other wastewater treatment projects.