KLARO
The classic
Our two-stage, fully biological wastewater treatment plant based on the SBR process (Sequencing Batch Reactor) has been offering a reliable and efficient solution for wastewater treatment for over 20 years. Since its introduction in 2001, the KLARO system has proven itself in countless applications. With continuous further development and the addition of further modules, the KLARO wastewater treatment plant always remains at the cutting edge of technology and has developed from a typical domestic wastewater treatment plant into a versatile all-rounder. The particular advantages of this wastewater treatment plant lie in its robustness and flexibility - even for demanding operating conditions.
- From domestic wastewater treatment plants (4 PE) to small municipalities (1,500 PE)
- For the treatment of domestic, commercial or industrial wastewater
- From new systems to retrofitting existing systems
The advantages of the KLARO wastewater treatment plant
- Separation of wastewater and technology
- Air lift instead of submersible pump
- Set-up kit made of stainless steel and wastewater-resistant plastic
- With integrated sludge storage and pre-treatment
- Stable process against impact loads and underloads
- Stable cleaning performance even in winter
- High operational safety
- Sophisticated technology - in use worldwide since 2001
- Independent of container material and geometry
- Sizes for all requirements up to 1500 PE
- All drain classes, all approvals
- Wide range of process customization options via the control system
- Low sludge accumulation - no desludging during the 38-week PIA test
- Only the sludge tank needs to be emptied
- Low energy consumption due to fine-bubble ventilation
- Low maintenance and user-friendly, automatic operation
Two-stage SBR purification process:
Effective wastewater purification in four steps
1st charging phase
In the first phase, the feed phase, the raw wastewater temporarily stored in the sludge storage tank or buffer is fed into the SBR reactor. For this purpose, our systems use a specially designed air lift that only pumps solids-free water into the reactor.
Thanks to the intelligent design of the air lift, a minimum water level is ensured in the sludge tank - without any additional components such as float switches. This not only saves material, but also makes the system particularly low-maintenance and reliable.
2nd aeration phase
In the aeration phase, the wastewater is aerated and mixed at the same time using membrane aerators mounted on the floor. The compressed air required for this is generated by an external air compressor housed in a control cabinet. Aeration usually takes place intermittently, i.e. at intervals, in order to use energy efficiently.
This ventilation has two main functions:
- Oxygen supply: The microorganisms in the activated sludge receive the oxygen necessary for their metabolism. This enables them to break down pollutants efficiently.
- Intensive mixing: Direct contact between the wastewater and the bacteria is maximized, making the purification process even more effective.
3. weaning phase
During the settling phase, the system rests for about 90 minutes without aeration. During this time, the activated sludge can settle.
- A sludge layer forms at the bottom, in which the microorganisms remain.
- In the upper area, a clear water zone is formed which is almost free of solids.
4. clear water outlet
In the final phase, the purified clear water is pumped out of the SBR stage. A specially designed air lift is used here, which offers several advantages:
- Protection against activated sludge: an integrated air barrier prevents activated sludge from inadvertently entering the siphon during the aeration phase.
- Minimum water level: The design ensures that the desired minimum water level is maintained in the system - without additional components.
In addition, excess activated sludge is fed back into the sludge storage chamber with the help of another pneumatic siphon. This keeps the system efficient and functional.
Highest cleaning quality with the KLARO system - tested and proven worldwide
With the KLARO system, you can achieve excellent effluent values that meet the standards of municipal wastewater treatment plants. This is proven by independent tests and the operation of thousands of plants worldwide. Our systems are regularly maintained and tested to ensure consistently high performance.
The system has been tested several times in accordance with the EN12566-3 standard by the PIA testing institute - also in combination with additional treatment stages such as phosphorus precipitation and hygienization. Voluntary special tests, such as the underload test and the vacation home test, confirm the robustness and versatility of KLARO technology.
- Outstanding cleaning performance: Clean and safe discharge water.
- Efficient nitrification: Reliable conversion of ammonium into nitrate.
- Constant effluent values: Stable even with changing loads.
- Reliable operation: No malfunctions or frequent interventions.
- Energy-efficient: Low power consumption for maximum sustainability.
- Minimal sludge accumulation: Proven sludge disposal frequency almost zero.
Discharge values
| Waste water values | Effluent values* | Efficiency* |
| COD | 31 mg/l | 96,1 % |
| BOD5 | 4 mg/l | 98,8 % |
| NH4-N | 1.1 mg/l | 96,9 % |
| Nges | 17 mg/l | 71,5 % |
| Pges | 4.2 mg/l 0.4 mg/l* | 50.4 % 95.0 %* |
| AFS | 10 mg/l | 97,1 % |
* with P-precipitation
Drainage classes
| C | Plants with carbon capture |
| N | Plants with carbon degradation and nitrification |
| D | Plants with carbon degradation, nitrification and denitrification |
| +P | Plants with phosphate precipitation |
| +H | Plants with hygienization |
In Germany, when approving a small wastewater treatment plant, the authorities specify the required discharge class ("purification quality"), which the plant must safely achieve during operation. With the KLARO system, all discharge classes are possible - all certifications and approvals are available. This means that operators of KLARO systems are also future-proof: if requirements become more stringent, it is possible to switch to a higher discharge class.
By the way: The requirements in Austria, Switzerland and other European countries are also met.
6 months of downtime are no problem for KLARO systems!
PIA test shows that KLARO also has the right system for vacation homes!
In many regions of Europe, there are vacation homes or second homes that are rarely used or not used at all for long periods of time. For a long time, it was assumed that SBR systems were not suitable for such applications. But the KLARO system proves the opposite.
A 5 PE KLARO system in the Carat tank with phosphorus precipitation was tested by the PIA testing institute. After the system was operated under normal load, the inflow was completely stopped for 26 weeks (approx. 6 months) so that the system went into so-called vacation mode.
Despite the long period of inactivity and the extreme underload, the KLARO small wastewater treatment plant was able to achieve impressive results after restarting:
- On the very first day after the restart, the BOD5 value was well below 10 mg/l.
- The Pges. value reached a value of 0.5 mg/l after just two days.
- The AFS values were below 10 mg/l within the first three days.
The results show that KLARO small wastewater treatment plants regenerate particularly quickly and achieve excellent effluent values even under extreme conditions. This underlines the versatility and efficiency of KLARO technology, which offers reliable treatment performance even with changing loads or long downtimes.
