KLARO underload

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KLARO wastewater treatment systems are tested for underload


Even with low water consumption KLARO wastewater treatment plants ensure highest performance.

The treated waste water is leaded directly into the nature, therefore the stability of a small wastewater treatment plant’s effluent classes is very important. Alternating loading of the plant (by force of personal, time of day, day of week, seasonal circumstances) can shake this stability – but not with KLARO small wastewater treatment plants.

Underload detection and recirculation


The "KLplus" control mechanism checks the fill level in the first chamber every 6 hours with an integrated pressure sensor. In the event of little or no inflow or low level, a purification cycle is not operated, but the system is merely marginally aerated. So electricity is saved and yet the batteries are preserved. The plant´s lifespan is independently adapted to the actual volume of wastewater with the automatic underload detection.

If no purification cycle has been operated three times in succession (i.e. a total break of 18 hours), the mechanism activates the surplus sludge lifter and transports water from the SBR chamber back into the 1st chamber. The duration and quantity is adjustable. Through this recirculation the first chamber fills and a normal purification cycle is started afterwards. Consequently, the batteries are provided with "fodder" once a day.

Examples of application:

  • Long-term under-occupancy (single family house)
  • Very low water consumption
  • Weekend houses
  • Holiday homes
  • Restaurants

Multiple lines


In extreme cases the plants are installed redundantly with multiple lines. The tanks are then set up in such a way that the biological cleaning takes place in two separate SB reactors. In low-season the SBR tank remains shut down. This is re-commissioned when the high-season begins. Activated sludge is then fed through from the operational tank to the tank that was previously shut down. Therefore, it is 100% operational immediately.

Examples of application:

  • Camping
  • Hotels

"Additional feeding"


Feeding a highly concentrated nutrient solution to the bioreactor is additionally possible with only sporadic or seasonal volume of wastewater. The consumption of the agent is minimal. Moreover, this is completely harmless, cost-effective and easy to handle. An adequate quantity of activated sludge, which furthermore features excellent settling properties, can be kept available with this agent.

One is independent from volume of wastewater with this method. Consequently, a KLARO plant can also be employed in cases in which one merely considered a pit without outlet to be possible.
We already have several years of experience with the “additional feeding method”, and we will gladly demonstrate various reference objects to you in this connection.

Examples of application:

  • Holiday homes
  • Garden allotments
  • Underload in connection with increased requirements