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TumbleOx Bioreactor

The TumbleOx™ Bioreactor utilizes an attached growth non-activated sludge process designed to provide biological treatment of BOD and ammonia. TumbleOx is a simple, easy to operate, and energy efficient method of achieving organics (BOD) removal and conversion of ammonia to nitrate.

TumbleOx Nitrification Reactor media TumbleOx Bioreactor tank with three drums TumbleOx Bioreactor media

The TumbleOx Bioreactor utilizes media stored in a rotating mesh drum which is partially submerged in the wastewater. The drum rotates, creating energy to mix the tank and ensuring thorough contact of the ammonia with the bacteria attached to the media. The media is shaped to create a bailing effect which cups and lifts the wastewater above the surface as the drum rotates. The wastewater is dumped from the media above the water surface, allowing oxygen to be dissolved into the wastewater as it falls back to the water surface. This continual movement of the media in and out of submergence creates a high level of dissolved oxygen in the tank which is necessary to remove BOD and convert ammonia to nitrate. Dissolved oxygen levels are typically maintained above 3.0 mg/L without the use of blowers or aeration systems. The small horsepower drive unit on each drum allows aeration and mixing to be achieved very efficiently with minimal power costs.

The constant movement and contact of the media pieces within the drum prevent excessive buildup of biomass on the media.  A thin, healthy layer of bacteria is maintained on the media surface for optimum process performance.

TumbleOx Features & Benefits

Parkson TumbleOx media
  • Utilizes a non-activated sludge, fixed film attached growth process to achieve biological treatment.
  • TumbleOx media is uniquely designed to provide a large surface area for bacterial growth. Low effluent BOD and ammonia values are achieved in a small volume. 
  • Tumbling action of the media dissolves high levels of oxygen into the wastewater without using blowers and aeration grids. Dissolved oxygen levels are typically >3.0 mg/L.
  • Attached growth media is housed within a rotating mesh drum to prevent washout.  Drum rotational speed is field adjustable to optimize performance.
  • Lower sludge yield versus activated sludge processes utilizing suspended growth.
  • Multiple drum configuration available to meet project requirements.

TumbleOx Bioreactors are Ideal for:

TumbleOx Bioreactor tank with three drums
  • Effluent polishing
  • Industrial pre-treatment
  • Small industrial and municipal biological treatment
  • Enhanced nitrification of lagoon effluent
  • BOD and ammonia removal in sludge dewatering return flows 

TumbleOx Bioreactors can be purchased individually for installation within site built tanks, or as three (3) drum pre-packaged units with tank. The pre-packaged units are completely factory assembled so site installation consists only of connecting inlet and outlet piping, and terminating field electrical wiring at one common control box.  Tank covers and splash guards are available add-ons.

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Features & Benefits


Attached growth media
allows biomass to be concentrated within a small area, allowing treatment to occur in a small volume

Improved function

Unique media design
accomplishes mixing and aeration without the use of blowers and aeration grids; D.O. levels are typically >3.0 mg/L

Improved function

Rotating drum concept
ensures thorough contact of wastewater with bacteria growing on the media; Constant tumbling of media controls biofilm thickness for optimum process performance

Low Power

Energy efficient design
with mixing and aeration provided by a single 1.0 HP drive unit on each drum

Reduced Maintenance

Fast and easy installation
with pre-packaged units which are factory installed

Reduced Maintenance

Plug and play design
with single inlet and outlet flow connections and one electrical termination

Provide various options

Design flexibility
with drums configured to best meet project treatment objectives


TumbleOx Nitrification Reactor media
TumbleOx Bioreactor media
TumbleOx Bioreactor with three drums
Parkson TumbleOx Bioreactor tank with three drums