The capacity of an activated sludge plant is dependent on the concentration of biomass and its performance is a function of the microbial population. 

Warden Biomedia plastic media provides a high surface area per unit volume of media with a low air side pressure drop.

It has been used to advantage in biological wastewater treatment processes for smaller municipal works and many industrial applications, including examples listed below.

Trickling filters (TF)

The media used in trickling filters needs a high surface area but must have a sufficiently open structure not to restrict the natural draft air flow. Traditional filters used blast furnace slag but modern plastic media like Biofil and Bioball provide a much higher surface area per unit volume of media with a low air side pressure drop. This makes these media ideal for replacing old media and uprating existing filters. Selecting the right media will also enhance nitrification by providing a protected area for the growth of nitrifying bacteria

Advantages of Warden Biomedia

  • Easy replacement of old or damaged media

  • Improved performance

  • Reduced “snails problems”

  • High resistance to erosion

Submerged Aerated Filter (SAF)

The submerged aerated filter consists of a series of cells containing buoyant media retained by a screen with air distribution fed from a blower. Because there is no limitation on air flow through the media, it is possible to use media with higher surface area per unit volume than in trickling filters.

Bioball and Biomarble media have proved highly efficient in SAFs.

The media can be selected to provide a protected area for nitrifying and denitrifying bacteria and similar species.

Advantages of Warden Biomedia

  • Buoyant media

  • High removal efficiencies

  • Maximised surface area per unit volume

  • High organic loadings

Moving Bed Biofilm Reactor (MBBR)

In moving bed biofilm reactors the buoyant media is free to move within an aerated reaction chamber.

The MBBR integrated fixed film activated sludge (IFAS) is essentially an activated sludge suspended growth process but with the biomass fixed to the media. It can perform all the same process variations such as nitrification, denitrification and biological phosphorus removal but with a higher biomass concentration which means higher organic loadings and smaller footprint.

Media can be easily retrofitted into existing activated sludge plants for flow and load uprates.

Small sized media with high surface area such as Biopipe 600, Biopipe+, Biotag, and Bioflo+, available in polypropylene or high density polyethylene, have a proven MBBR track record.

Advantages of Warden Biomedia

  • High surface area for biofilm attachment

  • Increased treatment capacity

  • Higher biomass concentration

  • Easy conversion of activated sludge to IFAS