The device for biological purification of sewage includes three parts:

• Mechanical purification.
• Biological purification:

  а) anaerobic bioreactor of cylinder in shape with assembled grates inside of it where is located a adsorbent (nozzle) in the form of mineral pieces for immobilization of microorganisms;

  б) direct – flow bioreactor for after purification with metallic gutter divided inside with vertical  partitions on the section filled as in the first bioreactor with 20-50 mm by magnitude pieces of mineral. The anaerobic stage of purification is carried out in the fist bioreactor, in the second bioreactor there are foreseen aerobic and anaerobic stages.

• Sediment processing: functioning of electric field, settler.

To   release purified water from the microorganisms of biomass by the way of sedimentation tank or first of electric field on the adsorbent (nozzle)  for increasing its adsorption capacity with the subsequent switching off the electric field and releasing a large amount of microorganisms biomass in the form of pasty mass which id easily washing away by the stream of liquid and settling down. Due to repetitive switching-on the current, biomass separates from liquid immediately. Due to repetitive switching-on the current, biomass separates from liquid immediately. So the same adsorbent (nozzle) may be used without regeneration during many years.