Answers to the most important questions about KLARO small sewage treatment plants and sewage treatment technology.

If you have any further questions, please do not hesitate to contact us directly.

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1. How often must the sludge be removed from the sludge tank?

As a rule, the following applies: "De-sludge as required"!
If an increased sludge level (70%, incl. measurement of floating sludge) is measured during maintenance, sludge must be removed.


2. How long does the sludge storage tank guarantee trouble-free operation at uninterrupted full load?
a trouble-free function of the plant?

KLARO small wastewater treatment plants are designed in such a way that full functionality is guaranteed for at least 12 months during permanent full load operation and compliance with the operator and maintenance obligations. At lower loads, this period is extended accordingly. Alternatively, a tank with larger sludge storage can be selected so that sludge must be disposed of at longer intervals.


3. Does sludge have to be pumped out of the SBR reactor, to ensure the operation of the small wastewater treatment plant?

No! The automatic continuous sludge recirculation directly at the tank bottom counteracts excessive sludge accumulation in the SBR aeration tank. Fine adjustments can be made by the specialist personnel during maintenance by changing the cycle times for the sludge discharge.


4. Why does the small wastewater treatment plant work in portions although there is no float in the plant?

The max. amount of water per cycle is defined by the set running time of the compressor for the pumping process. The special design of the pneumatic siphon ensures that the water level in the buffer tank cannot fall below a minimum level. Since the suction point of the siphon is well below the lowest water level, no floating sludge can be sucked in. All this works without a flap, mechanics, electric pump or float.


5. What has to be considered if the small wastewater treatment plant is permanently operated in underload?

We recommend our KLplus control system with automatic underload detection. In case of particularly low accumulation or longer absence, water is circulated. The bacteria necessary for the purification process are thus automatically activated and kept alive.


6. What is the advantage of the vacation time setting for the small wastewater treatment plant?

You can save costs specifically at the right time. With the KLbase control system, the vacation mode is set manually; with the KLplus, this is done automatically.


7. How often and with what effort does the small wastewater treatment plant have to be maintained?

For a KLARO small wastewater treatment plant with standard mains failure detection, only two maintenances per year are required according to the building inspection approval. This mainly involves checking the function of the system, checking and, if necessary, readjusting the cycle times of the control system and taking a water sample to examine the effluent quality. The concept of the purely compressed air-driven KLARO small wastewater treatment plant is maintenance-friendly and cost-saving, since no mechanical or electrical aggregates are housed in the septic tank.


8.  How high is the energy demand of a KLARO small wastewater treatment plant? 

Compared to many other plants with SBR technology, KLARO realizes savings potentials of partly 75% by using intelligent controls and automatic underload detection. The energy consumption of just over 10 euros per year and per population equivalent makes KLARO one of the most economical small wastewater treatment plants in the world.


9. How costly is the retrofitting of a small wastewater treatment plant?

Retrofitting an existing plant requires consultation with our partners. The building fabric must be checked, and the tightness to the outside and between the chambers must be ensured. This is the only way to ensure that the legal requirements for effluent values can be met on a permanent basis.


10. If something breaks - how should the cost of a repair be estimated? 

The effort is very low! Since technology and wastewater are separated, in the event of a failure of a technical component, it usually only has to be replaced at the control cabinet. No one has to enter the pit, no cable has to be loosened, because only plug connections according to VDO/VDE are installed.



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