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.