The AnoxKaldnes™ Hybas™ hybrid process combines AnoxKaldnes™ MBBR biofilm technology and an activated sludge process in the same tank. The Hybas™ hybrid process is especially suitable for nitrogen removal from municipal wastewater but can also be used for some industrial applications.

Features and benefits

  • Compact solution requiring little process volume.
  • Reduction of organic material and nitrogen.
  • Upgrading of existing activated sludge systems to comprise nitrogen removal or to improve the capacity of the existing nitrogen removal process.
  • Increased nitrification capacity to the aerated activated sludge volume with use of carriers.
  • Less sensitive to temperature variation.

High denitrification with reduced suspended sludge age

Thanks to the biofilm solution, the long suspended sludge age normally needed to achieve nitrification in the activated sludge (AS) can be reduced. A reduction of the sludge concentration in the AS will also lead to less sludge load on the secondary clarifiers.

Another benefit is that a short sludge age will often reduce the risk of growth of filamentous bacteria and generally, the biological activity is higher in an AS process with low sludge age than in one with a high sludge age.

Design factors

The following elements are necessary design factors, which have to be considered to create a well working Hybas™ system.

  • Media type
  • Aeration system
  • Dissolved oxygen concentration
  • Effluent NH3-N concentration
  • Basin configuration
  • Hydraulic profiles through the basin

Related product

AnoxKaldnes™ MBBR