Sludge Treatment
Sludge Dewatering

Secondary sludge from the treatment of wastewater can be used in a variety of ways, depending on the location of the wastewater treatment plant. Examples of use are:

For energy generation
Application as fertilizer on soil (only outside the EU)
Disposal by incineration

In order to keep the costs as low as possible in the event of disposal or to avoid unnecessary nitrogen input into the soil as well as the entry of potential heavy metals and microplastics when used as fertilizer, sludge treatment is required.

The intended use of the sludge results in the following different requirements for sludge treatment:

The activated sludge should leave the plant as stabilized as possible and odor-free
As little precipitant as possible (often polymers) should have been added to the secondary sludge during dewatering
The sewage sludge should have the highest possible degrees of drying for disposal and further treatment (22 – 30 % DS)
The sludge should have the highest possible degrees of drying for incineration (70 – 90 % dry matter)

Systems for pre-cleaning and pre-treatment

In order to bring the surplus sludge of a sewage treatment plant into exactly this condition, as required by the legal framework and your preferences, we use the following technologies, among others:

Sludge thickening (static or mechanical) via sludge discharge systems (BSK^®-Decanter) in sedimentation tanks, drum- and disc thickeners
Sludge stabilization via post-aeration or chemical addition of lime or NaOH
Sludge dewatering via high-performance centrifuges, belt filter presses and screw presses
Drying of sludge via solar and cold air systems
Sludge humification