Combining The Use of Engineered and Natural Plants in Activated Sludge Systems

John Koumoukelis, Hydroflux Epco Pty Ltd

Integrated Fixed Film Activated Sludge Plants (IFAS) rely on the use of a media on which a biofilm is grown, which results in a compact footprint as a majority of the biomass is fixed to a high surface area as opposed to being suspended.

A recent development of this process has been to combine naturally occurring plants with engineered media. To put simply, a botanical garden is placed on top of the IFAS reactors, with the plant roots penetrating into the reactors. 

The interaction of enzymes and various organic acids from the plant roots to the bio-media creates a diverse biology, leading to increased process stability, less sludge production and lower energy demand when compared to conventional activated sludge plants. And the sewage treatment plant looks like a botanical garden.

Large scale installations in Europe have been in operation for 5 years. This presentation discusses the design, operating and performance data of a 500,000 and 5,500 EP treatment plant using this process.