The points to watch for all biorotors or biodiscs are :
- prolonged stoppages (power cut for example)
- the media clogging
- the mechanical sturdiness of the construction
- greasing the bearings
The pamco biorotor responds to these points in the following way :
Prolonged stoppages
In the event of a prolonged stoppage the biofilm that is above the water dries out and creates an imbalance in the weight on the biorotor. When re-starting the biorotor, the torque imbalance (drift) can be too great and can lead to mechanical breakdowns.
pamco solutions :
- a torque measurement system is installed to stop the equipment on a torque threshold that is too high
- after a too long a stoppage, the tanks are drained (fixed pump, manual or automatic valve, etc…)
- use of a variable speed drive for a slow restart of the machine after a stoppage
Media clogging
Some poorly designed biorotors insufficiently protected against floating matter or sized too ‘tight’ can become clogged with waste or with excessive growth of the biomass.
pamco solutions :

- the sludge decantation and digestion tank is always a large size
- a floater barrier is fitted at the output of the sludge decantation and digestion tank
- avoids disturbing the settling area of the sludge decantation and digestion tank with the rise of gas fermentation bubbles
- avoids a too great a pollutant load at the 1st stage level of the pamco biorotor
- arranges the media around the axis in such a way that the troughs emerge from the water surface perpendicularly when the media leaves the water. This allows the water and the biofilm to drain, and a cleaning of the biofilm.
With all these precautions there is no risk of clogging, even with a cellular-type media.
Mechanical sturdiness of the construction

At the core of a biological reactor is the biorotor, it is important that this mainly mechanical equipment is as sturdy and long-lasting as possible.
pamco solutions :
- the pamco biorotor is a proven, simple mechanical design that is robust.
- the pamco biorotor has been in production for more than 30 years and over the years improvements have been made to its construction/assembly method and in the choice of its component materials.
- in the standard version, the materials used are :
- central tubular shaft in ST37 mild steel with a 300 µm epoxy coating. The shaft is not submerged in the effluent
- full shaft ends in ST57.2 steel, with no coating
- cellular-type media (various densities) in polypropylene (PP)
- stainless steel framework fixing media to the shaft
- safety taken a great deal into account in sizing, especially the central shaft
- very strict manufacturing monitoring and control
Without a doubt, pamco biorotors are the most industrial and the most sturdily built biorotors on the market.
Greasing bearing
Regular greasing of the bearings is necessary for a good lubrication of the central shaft ends.
pamco solutions :
- because a tubular central shaft is used, only 2 support points, therefore 2 bearings, are needed, even for very long biorotors (over 10 m)
- therefore there are no intermediate bearings between 2 levels that are difficult to access
- automatic greasing systems supplied (cartridges ideally)
- greasing the bearings and all running maintenance operations are done from the exterior, without having to go inside the biological reactor, and so without risk to the operator.