Abwasserverband Zirl und Umgebung

Biogas

Project Name: Abwasserverband Zirl und Umgebung
(click to open fact sheet and detailed project description)

Project Description:

The wastewater treatment plant in Zirl is designed for 61,500 population equivalent and has an anaerobic digester with 1,350 m3. In Austria on average wastewater treatment plants can cover 43% of their energy demand by anaerobic digestion of sewage sludge.

By using organic waste as co-substrate the plant in Zirl reached to cover the whole electricity demand. They use co-substrates like faulty batches, expired bread, grease separation material and coffee grounds from Nespresso-taps. From a Truck-Load with 23 tons of Nespresso-taps biogas with an energy equivalent of 23.500 liters of fuel oil can be produced. All in all approximately 3,000 tons/year of organic waste is used as substrate additionally to the arising sewage sludge. The waste like Nespresso-taps is pre-treated by a private waste management company using a hammer mill.

The wastewater association in Zirl is cooperating with different partners from industry and science to further optimize the use of digester volume of wastewater treatment plants.

Technology at a glance

  • Biogas production: 700.000 m3 / year
  • Installed power: 175 kWel
  • Digester: 1x 1.350 m3
  • Substrates: expired food, faulty batches, grease separation material, coffee grounds, …
  • Input waste/substrate: 3.000 t/year (68% sewage sludge, 32% organic waste)
  • Operating hours: 8.000 h/year

External link to further information: www.avzirl.at

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