Compact Systems

«A thousand systems installed and over 30 years experience.»

The Bio Spiral Compact Sewage Treatment Plants consist of a buffer tank, cup lift, rotating bio-solids plates and post clarification filters. In the system biodegradation of organic matter in the wastewater is carried out by micro-organisms growing on the plates. Solids are removed in the clarifier and the filter stage.

The plants can be built in sizes from 10-400 PE in steel tanks or for installation in concrete tanks.

Areas of Application

  • Smaller municipalities and hamlets
  • Holiday settlements
  • Hotels and Inns
  • Mountain huts
  • Motorway service stations
  • Industry and Commerce

Special Advantages

  • High process stability
  • Low space requirement
  • Minimal power requirements
  • Compact design
  • Simple and robust machine technology
  • Low operating costs
  • High operational reliability
  • Insensitive to shock loads due to its continuous recirculation and equalization tanks
  • Filtration of the effluent to tertiary standards


The mechanically treated wastewater flows into the buffer area of the plant from which the wastewater is continuously fed into the biological stage. Biological treatment consists of a rotating biological contactor and a cloth filter. Growing on the immersion elements, biomass is brought alternately in contact with air and waste water, the bio-mass then consuming and removing the contaminants. The resulting biological sludge is separated from the treated wastewater in the filter and returned to the pre-treatment.


These systems have an integrated buffer tank with cup lift for continuous feed. The rotating biological contactors have diameters of 1.2 or 2.0 m and up to 60% immersion. They rotate around there own axis, driven by a gear motor. One or two downstream pile cloth media filters are driven by the shaft of the rotating biological contactor. All functional units are mounted in steel tanks or concrete.