Separation techniques

Research project with the Münster University of Applied Sciences

Separation techniques: Key for processing digestate and slurry

In this research project, various possible process techniques were investigated with regard to the separation of liquid manure for direct use in biogas plants with regard to continuous operation, the recording of separation performance and the influence of liquid manure ageing on nutrient separation.

Results

  • Separation with the Klass spiral filter generates electricity costs of approx. 0.40 €/t per slurry used
  • Throughputs of approx. 400 kg/h are achievable for fermentation residues. Here approx. 55 % phosphorus can be separated and a solid with approx. 18 % dry matter can be achieved
  • Throughputs of approx. 600 kg/h can be achieved for cattle manure. Here approx. 50 % phosphorus can be separated and a solid with approx. 17 % DM can be achieved
  • Specific nutrient separation is more difficult to achieve with cattle manure
  • Throughputs of up to 2,000 kg/h can be achieved for pig manure. Here approx. 19 % phosphorus can be separated and a solid with approx. 20 % dry matter can be achieved
  • Phosphorus separation increases with slurry age and almost reaches the separation efficiency of a centrifuge with small size and power consumption (max. 2.5 kWh/t raw slurry)

Products used