A new moving bed biofilm reactor has been developed in Norway. The biomass is attached to carrier elements that move freely along with the water in the reactor. It is demonstrated in the paper that this results in a very compact reactor and a very efficient biomass. Experiences from pilot and full-scale testing of the reactor in municipal and industrial wastewater treatment applications are presented and discussed.

A novel moving bed biofilm reactor has been developed, where the biofilm grows on small, free floating plastic elements with a large surface area and a density slightly less than 1.0 g/cm³. The specific biofilm surface area can be regulated as required, up to a maximum of approximately 400 m²/m³. The ability to remove organic matter from concentrated industrial effluents was tested in an aerobic pilot-plant with two moving bed biofilm reactors in series and a specific biofilm surface area of 276 m²/m³. Treating dairy wastewater, the pilot-plant showed 85% and 60% COD removal at volumetric organic loading rates of 500 g COD/m³h and 900 g COD/m³h respectively. Based on the test results, the moving bed biofilm reactors should be very suitable for treatment of food industry effluents.