Sludge Mixing

A high ratio of back mixing is essential. Mixing incoming sludge with dry sludge results in a higher dry solid content of a less sticky nature.

Vadeb Drying Principle

The Vadeb® drying principle eliminates potential hazards, like odour nuisance and overheating. Read more about our advanced drum drying technology.

Back Mixing » avoid fouling

The back mixing process avoids possible fouling of sludge cake with a sticky nature (sludge cake with a dry solids content of 40-50%) inside the rotating drum.

More about backmixing in drying systems

Backmixing is a process where the sludge cake is mixed with already dried material and dried fines to form a non sticky mixture with approx. 65% DS. It is necessary to overcome the sticky phase inside the drum and to process the dry fines into a dust-free granule.

The back mixing unit consists of:

  • A wet cake dosage bin
  • Dry-sludge dosage bin
  • Paddle or high speed plough mixer
schematic overview DDD sludge drying system
Example layout Direct Drum drying (click to enlarge).
Example layout Indirect Drum drying (click to enlarge).

Main design principles of a Vadeb Drying System (sludge):