Tube-bundle clarifier

The separation of solids from liquids is carried out in water and waste water technology, e.g. by settling tanks, where solids can settle under defined conditions. Sedimentation refers to the separation of suspended solids from a liquid with the aid of gravity. The efficiency of a settling tank is characterised by the hydraulic conditions in the tank. The main criteria for this are:

• Specific surface loading
• Sludge loading
• Processing time, i.e. dwell time
• Flow velocity
• Laminar, i.e. low-turbulence flow pattern

An increase in waste water load or greater demands on the effluent quality makes the construction of larger and more efficient settling tanks a necessity. It is therefore necessary to develop more effective solutions.

A marked improvement in sedimentation of undissolved components from liquids is achieved by the installation of a tube-bundle clarifier. This enlarges the settling surfaces several times. The bundle tube constructed at a 60° angle in a cross design achieves the shortest settling routes and fastest concentration of the sediment-forming solids and flakes.

If the sedimentation and separation of undissolved components in existing settling tanks is poor (flakes output), so a substantial improvement can be achieved with the tube-bundle clarifiers.

The tube-bundle clarifiers are supplied in individual modules. Plates arranged in parallel and vertical walls form tubular channels with square cross sections. The tubular channels of two adjacent plates are positioned crosswise across from each other so that the approximately 3 m long, 0.75 m wide and 0.52 m high possess an exceptionally high rigidity despite the low weight of about 25 kg. The material used is resistant to sunlight and biological influences.

The materials conform to the German food law and may be used accordingly in the drinking water. It is installed on a supporting structure that is attached to the tank wall or to the spillways. Any necessary modifications to the sludge raking facilities are in most cases carried out without difficulty. In some cases, provision needs to be made by an additional array of guide walls for an even flow of the modules.