Logo: FlexBio Technologie - Energie aus Abwasser

It is important to us that no questions remain unanswered.

Here you will find answers to the most frequently asked questions from our customers on the subject of wastewater treatment and information as well as notes on our process and technology.

About us

FlexBio Technologie GmbH was founded as a spin-off from a university. The spin-off was preceded by a research project called “FLEXBIO”. This gave the company its name. In this context, a new process was developed that enables very effective fermentation. The method can be used in particular for liquid substrates and various organically polluted wastewater. The special thing about it is that gas production and thus energy generation can take place as required.

  • The first innovation is flexibility. Flexible / changing substrate / wastewater use, flexible gas / energy production, flexible / modular construction.
  • The second innovation is the effective and efficient removal of wastewater contaminants in just a few process steps and a lasting positive energy balance.
  • The innovation was developed by the founders themselves and put into practice. The company owners are therefore direct know-how carriers.
  • The innovation has already received several awards from various institutions.
  • Another special feature is that our systems are developed, built and maintained entirely by ourselves. The core competencies remain with us and enable us to perfect the process in depth at any time.
  • Customers receive a binding performance commitment from us.
  • Before placing an order, our customers can see for themselves by carrying out on-site tests with our mobile test systems.
  • The customer receives a turnkey system.
  • Our systems have a compact and modular design.
  • Expansion is possible at any time, so that the wastewater treatment system can “grow” with the business.
  • Our systems are always developed by us for the customer exactly according to customer requirements.

In general, the FlexBio process can purify any organically polluted wastewater. The use of the process is particularly profitable in the food and beverage industry as well as in agriculture. The non-food sector such as biodiesel production and the paper industry can also benefit from the process. Numerous other applications are also possible. We would be happy to analyze your wastewater and discuss its potential with you. Contact us .

Yes, municipal wastewater can, like in any “normal” sewage treatment plant, be cleaned to direct discharge values. In addition, biogas is also produced here for energy recovery.

No, but the composition of the wastewater is very individual, so that we often recommend preliminary tests directly at the customer (on-site examination with our mobile demonstration systems) or at our technical center.

That depends heavily on the organic load. In general, up to 95% of the organic pollution is converted into biogas. A beverage manufacturer’s wastewater can deliver up to 3 m³ methane or 30 kWh of energy per cubic meter of wastewater. Up to 60 kWh of primary energy can be obtained from the same amount of wastewater from a slaughterhouse. This creates an energy surplus in the treatment process (positive energy balance). You can use the resulting biogas directly on-site and generate a large part of the energy required in operation yourself.

We also offer attractive leasing and hire-purchase options. Here is yours Financing options .

Yes it is possible. Our systems can be equipped with a photovoltaic roof and can also be installed and operated in remote areas. You gain biogas in order to cover part of your energy consumption. In addition, you can use the treated wastewater to irrigate the green spaces.

FlexBio was founded in 2014.

Biogas plants

Maximum 1 kWh / m³.

Average of 5 kWh / m³ surface water.

Yes, supply lines for heating and electricity as well as inflow and outflow lines for the water and possibly a biogas line to the container must be laid.

Usually up to 10,000 mg / l COD, although higher loads are possible.

Phosphates and nitrogen compounds can be broken down. In addition, the pH value is brought into the neutral range.

The system measures all relevant parameters and controls itself in such a way that the limit values are permanently adhered to. The water is therefore always conductive.

The containers have a modular structure and can be expanded at any time.

Yes, the container has to be serviced, for this a six-monthly maintenance by the FlexBio Service is planned.

No, the systems run fully automatically. All that is required is a daily visual inspection.

The container must stand on solid ground. Our recommendation is a strip foundation.

The systems are housed in a standard overseas container. Either 6m or 12m long. You can determine the color individually, just like buying a car.

We take care of all the necessary documents and submit them to the water authority. If a building application is required, we can also provide this.

Meat and food industry

In the case of large amounts of wastewater, the cleaning system is installed in round tanks. A container solution is only retained with special solutions.

No, the technology is characterized by very little maintenance.

Maximum 1 kWh / m³.

With cold wastewater, an average of 5 kWh / m³ is used. With a warm waste water flow (from 30 ° C) no additional heat is required.

No, the fats are converted directly into energy-rich biogas. Fats are completely broken down and no longer have to be disposed of elsewhere.

No, the anaerobic biofilm adheres to the packing and is not carried away by fats.

The system technology meets all hygiene standards.

In terms of investment costs, the cleaning system is similar to classic cleaning technologies. The running operating costs are significantly lower than with traditional methods. When using biogas, the payback period of the system is in most cases less than 3 years.

No, alcohols are organic compounds that are very easily degradable.

Industrial wastewater

Yes. However, this cleaning is not done biologically, but physically by means of adsorption with a granulate.

Yes, various impurities can be removed. Depending on the type of load, cleaning requires additional cleaning stages. We offer mechanical, chemical, physical and biological cleaning stages. These levels can be combined as required.

Yes, this wastewater can also be cleaned. However, no biogas is produced here.

Maximum 1 kWh / m³.

Cold wastewater consumes an average of 5 kWh / m³. With a warm waste water flow (from 30 ° C) no additional heat is required.

No, there is no need for pre-cleaning or the like on site. FlexBio wastewater technology offers all the necessary cleaning stages from a single source. We will create a concept for you with all the cleaning stages to be installed.

Options to install a FlexBio system:

  • New building: standalone solution
  • Conversion: parts of your old system are replaced
  • Extension: Parts are added as a supplement

Demonstration systems


Since this is a biological process, it requires an adaptation time. We also want to get meaningful results that depend on the duration of the experiment.

The mobile system is dimensioned in such a way that it can be upscaled to a larger system.

The integrated template is filled continuously, for example every hour, depending on the throughput, so the results are practical.

Depending on the quality and origin of the wastewater, approx. 500 – 4000l / day are treated.

Yes, there will be an on-site briefing for the staff. They are responsible for the regular sampling of the inlet and outlet as well as for the condition and visual inspection.

It takes about 10 minutes a day. Weekend care is not necessary.

There is a weekly analysis report. At the end of the trial period, a final report is drawn up that includes the results / evaluation and recommendation.

While the experiment is being carried out, the treatment stages are continuously monitored via remote access.

Yes, we will always have to spend a lot of time and you will gain valuable knowledge about your wastewater, even if it is not suitable for the proposed treatment.

Yes, this will be adjusted in the course of the investigation.

No, depending on the circumstances, there is only one installation of a waste water extraction point.

No special permit or construction work is required. However, you will receive a safety briefing in system operation. We will also provide you with all the information and instructions on security measures and restrictions. The AFBBM-1.MV mobile demonstration system must be operated in accordance with the operating instructions supplied

Measurement parameters and analysis data

According to the integrated measurement technology, the following parameters are continuously recorded online:

  • Volume flow of the wastewater (flow rate, volume counter)
  • Biogas volume (raw gas)
  • Gas composition: CH 4 , CO 2 , H 2 S, O 2
  • Gas temperature (for determining the standard volume)
  • Absolute pressure biogas (for determining the standard volume)
  • Process temperature (in all stages)
  • Oxygen concentration of the activation
  • pH value (in all levels)
  • Redox (in all stages)
  • Conductivity (in feed)

Samples are taken at defined (labeled) sampling points as instructed by the operating staff. In order to assess the performance of the system, measured values are regularly recorded online and offline. Offline analysis is wastewater analysis that can only be defined to a limited extent using online measurement technology. Therefore, the following measurement parameters are repeatedly recorded in laboratory analysis:

  • COD concentration in the inlet and outlet
  • Nitrogen concentration in the inlet and outlet
  • Phosphorus concentration in the inlet and outlet

Alternatively, the sample analyzes can be arranged at any recognized / accredited laboratory. If outsourced, the laboratory reports must be made available to the contractor promptly.

Samples should be sent in the prepared and prepaid shipping bags on Wednesday at the latest so that the sample arrives before the weekend. The laboratory analysis runs at our partner laboratory ( Laboratory for Environmental Analysis, HAWK University, Faculty of Resource Management).

The treatment system is a multi-stage system with an integrated anaerobic main cleaning system and a downstream activation stage with a built-in MBR system (membrane bioreactor). The anaerobic fixed bed fermenter enables an effective removal of the organic load with methane production. This combination is unique and includes all levels.

Installation site

It is set up outdoors or in a partly open, well-ventilated hall. The final installation location will be agreed with the contractor.

It is set up on a level, paved surface (asphalt or concrete).

The mobile demonstration system is spatially close to:

  • the potential wastewater withdrawal point (max. 30m),
  • Drainage for purified water (max. 20m) as well
  • Power connection: 400V, 3 Ph., CEE three-phase plug 400V / 32A (Attention: do not use a FI protection fuse); Maximum distance from the installation site 20m.
  • Minimum installation area: 9 mx 4 m.
  • Sufficient maneuvering space to park the trailer at the installation site.
  • Connection of the supply line to an on-site pressure line (max. 1 bar) with a 1 inch external thread connection with a ball valve or slide valve. The demonstration system controls a valve internally and fills an internal template under level control.
  • Alternatively, the wastewater can be taken from a receiver or a pump shaft via the supplied pipe.
  • There is also the option of integrating a submersible pump (included as an accessory), which can be connected to the mobile system and controlled via the system.

Is your question not included?

Our customer service will of course be happy to answer any further questions you may have. Alternatively, you can also use our contact form on the Contact page.