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Brewery Rittmayer Hallerndorf GmbH & Co KG

Anaerobic wastewater treatment with energy generation

The Rittmayer brewery is one of the oldest breweries in the Forchheim region. The family business was founded in 1422. The former count’s brewery was the supplier of the Harendorf hunting lodge. The brewery was even awarded a certificate by Count Kulmbach for the quality of its good beer. Master brewer Georg Rittmayer looks back with pride on the centuries-old brewing tradition and loves his craft. Under his management, the family business has developed into a small and medium-sized enterprise. The carefully selected assortment includes 20 different types of beer, three of which are seasonal. The brewery produces 30,000 hectoliters annually.

Rittmayer Logo

Initial situation

The brewery from Upper Franconia is investing in a mixing and equalization tank as well as an anaerobic FlexBio wastewater treatment plant, which will provide additional ecological support for the production processes from now on. This enables the Rittmayer brewery to pre-treat their wastewater generated in the production process to household levels, while at the same time converting the biogas produced into green electricity and heat to replace fossil fuels. In the first step, the mixing and equalization tank is used for wastewater pretreatment in the brewing process, while the FlexBio plant handles anaerobic wastewater treatment. Both elements make it possible to reduce the organic load in wastewater by around 80 percent to the level of household wastewater. At the same time, a locally operated gas storage tank is fed by the wastewater treatment plant, providing biomethane for the combined heat and power plant to generate green electricity and heat for the plant. The Rittmayer brewery is thus continuing its orientation towards a sustainable production process and is taking on a pioneering role for other breweries in the region.

Data and facts

Wastewater information

  • Pollution COD: 2,000 – 3,000 mg/l
  • Purified water (indirect line) COD: < 1,000 mg/l

Own energy generation

  • 17,000 kWh electric per year
  • 26,000 kWh thermal per year
  • Biogas production: 2.5 m³/h

Processing capacity

  • 40.000 m³ per year

CO2 saving

  • 9,000 kg per year

FlexBio wastewater treatment

  • Construction time of one month (completion 2021)
  • A FlexBio container incl. anaerobic pre-treatment, gas storage, gas treatment, combined heat and power plant and control technology (type FLEXBIO-AF-100 HC)

What our customers say

“We are very pleased to be able to further raise our environmental standards in the filling and brewing process after an extensive building permit process and a corona-related shortage of raw materials or construction materials. The aerated mixing and equalization tank from Flexbio meets the latest technical as well as the highest ecological standards. The measurement and control technology used ensures automated, process-stable wastewater pretreatment. Our parallel commissioned wastewater treatment plant supports the anaerobic wastewater pretreatment in order to biodegrade it in the best possible way. With a biogas generation system connected to this, we are able to generate our own CO2-neutral electricity with around 612,000 KW/h of gas via the wastewater treatment plant and save around 137 tons of CO2 in the process.”

Georg Rittmayer, Managing Director of the Rittmayer Hallerndorf Brewery


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