High-performance digestion for sewage sludges

The digestion of sewage sludge resulting from the treatment of municipal or industrial waste water does not only stabilize the sludge and minimize odours, but also reduces the amount of residues by decomposing organic parts. Thus, disposal costs are considerably reduced.

SBS offers an effective high-performance digestion for the treatment of sewage sludge. The system uses a special plug-flow tank equipped with levels of perforated plates. After the thickened sewage sludge has been tempered it is fed to the slim, tall fermenter (height/diameter ∼2.5 m) and mixed by means of an external pump.

The SBS high-performance digestion is designed as either one-stage mesophilic or two-stage mesophilic/thermophilic depending on the throughput of sewage sludge and the desired degree of decomposition. In addition, the high-performance fermenter can be used as a highly-loaded upstream treatment stage to improve the efficiency of existing digestion plants.

The digestion plant can be supplemented with a microfiltration plant to separate filtrate during the digestion process. This further enhances the degree of decomposition in the system.

Due to the special process design, the SBS high-performance digestion has considerable advantages compared with conventional digestion towers:

  • Treatment times are considerably reduced: 5 12 days instead of 20 30 days.
  • This means smaller fermenter volumes.
  • High decomposition performance and biogas production.
  • Excellent drainage of the sewage sludge is possible.
  • Low power consumption due to impulse mixing system.
  • No problems with foam.
  • Lower space requirement, ideal for retrofitting sewage treatment plants.

Operation and maintenance of the digestion plant are nevertheless simple.

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