In wastewater sludge handling, a centrifuge is a mechanical device use for dewatering sludge by applying centrifugal force. It is a widely use method for separating solids from liquids in various industries, including wastewater treatment plants.

System Components

Bowl or Drum: The rotating component where the sludge is place. It is usually cylindrical in shape and has perform walls or filter media to allow liquid drainage.
Screw Conveyor: It helps in conveying and compacting the sludge against the bowl walls. As the drum rotates, the screw conveyor moves the sludge towards the discharge end.
Drive System: Provides the power to rotate the bowl or drum at high speeds.
Differential Speed Control: Some centrifuges have the ability to control the speed difference between the drum and the screw conveyor. 

Process Description

A centrifuge operates by rotating a bowl or drum at high speeds, creating centrifugal force that pushes the sludge against the walls of the drum. The centrifugal force causes the solid particles in the sludge to settle and compact against the drum wall, while the liquid phase (centrate) is force to move towards the center and is discharge.

As the sludge is fed into the centrifuge, the rotating drum creates a high centrifugal force that separates the solids from the liquid. The dewater solids accumulate near the bowl wall, forming a cake, while the clarifie liquid is force to move towards the center of the drum and is discharg through appropriate outlets. 

Significance & Advantages

Centrifuges are known for their high dewatering efficiency and ability to handle a wide range of sludge types, including municipal wastewater sludge, industrial sludge, and biological sludge. They are particularly useful when dealing with sludges with high water content.

Centrifuges can achieve significant reductions in the moisture content of the sludge, resulting in a more concentrate and easier-to-handle product. The dewater sludge cake produce by centrifuges can be further processed or dispose of, depending on the specific requirements and regulations.