The biofilm required for the cleaning performance colonises on the floating support medium with a very large surface. Oxygen is supplied by a blower which is placed outside the plant in a control cabinet.
Benefits of fluidised bed plants:
- low sludge volume
- good cleaning performance
- good cleaning performance even with underload
- simple retrofitting possible
- maintenance required only once or twice per year
- proven system
The main advantage of a ClearFox fluidised bed procedure is the high biomass concentration (>21gTS/L) which allows for a small reactor design. This saves costs while reaching a high cleaning performance.
Wastewater cleaning with the fluidised bed process
Cleaning of the wastewater is performed in the fluidised bed or fluidised/floating bed process, comparable to the fixed-bed process. The bacteria in form of a biofilm is not growing on a fixed support medium but on a free floating support medium. The support medium is given into the tank chamber during installation so that the bacteria can colonise there.
ClearFox FBS (fluidised bed system) small sewage treatment plant with fluidised bed reactor
The FBS is a small sewage treatment plant of the latest generation, operating according to the fluidised bed process.
The natural wastewater accumulation flows freely through the plant. An integrated restriction makes sure that the flow is equalised in order to optimise the physical and biological processes.
This technology requires no rotating parts in the wastewater. Sludge is transported via a maintenance-free airlift-pump, operated with compressed air.
Plant structure with fluidised bed
The plant always includes:
- a mechanical cleaning stage
- a fluidised bed reactor
- a secondary sedimentation chamber
Mechanical cleaning stage
The mechanical cleaning stage fulfils the following tasks:
- The wastewater polluted with coarse material flows into the plant in a free gradient. The coarse material is separated in this first stage by mechanical separation (separation by gravity).
- In addition, the surplus sludge from the biological process is stored in the mechanical cleaning stage.
Fluidised bed reactor
The wastewater is ventilated intermittently in the fluidised bed reactor. An accordingly designed aeration system provides ventilation in fine bubbles. Micro organisms are thus supplied with oxygen, and the entire content of the reactor is blended. A blower is used to produce compressed air. The micro organisms are fixed on small plastic form parts.
Secondary sedimentation chamber
In the secondary sedimentation chamber, the cleaned wastewater is separated from the bio mass by sedimentation. The sedimented biomass is delivered in corresponding intervals by an airlift-pump as surplus sludge into the pre-chamber.