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Experiences from the biogas plant

The AU Foulum biogas plant was commissioned in the autumn of 2007 and after a short running-in period, the plant was soon in full production.

The feedstock for the plant consists of a mixture of crops and animal manure with the addition of vegetable glycerol from the production of biodiesel.

The addition of glycerol has gradually been increased, and the plan is  to substitute this raw material with for example meadow grasses from landscape conservation.

 

Raw materials 2010:

  • Maize and grass silage: 8 t/day
  • Straw bedding and fodder remains: 6 t/day
  • Mixed slurry: 63 t/day
  • Vegetable glycerol: 2,7 t/day

 

Gas Production
The gas production has increased steadily since the start-up and the daily production is currently 4800 m3. This converts to approx. 10 Mwh electricity and 14 Mwh heat per day.

The actual biogas production is generally at or slightly above what can theoretically be expected with the biomass used, which indicates that the process is efficient and stable.

The fat content in the form of volatile fatty acids (VFA) is regularly monitored and the level is low and stable, which again bespeaks a robust and stable process.