Veolia Water Technologies AnoxKaldnes has launched a new generation of biofilm carriers for moving bed biofilm reactors: AnoxKaldnes Z-MBBR. The new carrier is the result of two decades of development work.
Z-MBBR by AnoxKaldnes, biofilm in 3D.
A different approach to carrier development
Traditionally, carrier development has aimed for larger protected surface area, but has allowed for a more or less uncontrolled growth of the biofilm.
This lack of control of biofilm thickness is a major uncertainty for process design based on carrier surface area, and also limits the applications for which the MBBR can be a competitive solution.
Z-MBBR - The new dimension
The new carrier design is covered with a grid of defined height, allowing the biofilm to grow on the outside of the carrier in a protected environ-ment.
Due to scouring from other carriers, the biofilm cannot grow higher than the grid height, and so biofilm thickness is controlled.
Applications of Z-MBBR
As all process limitations related to uncontrolled growth of biofilm and clogging of carriers are eliminated with the Z-carriers, they are especially useful in applications where the biofilm tends to grow thick, such as nitrification at higher organic loads.
Z-carriers with different biofilm thicknesses have been evaluated for different applications, with very interesting results. As for example, extremely thin biofilms have shown to open for a new, more efficient application of mainstream ANITA Mox.