Influence of the TS content

Research project with the Münster University of Applied Sciences

Influence of the TS content in the solid matter of pig slurry on the separation efficiency of nitrogen and phosphor as well as on methane gas production when using the Klass spiral filter

In this research project the Klass spiral filter was tested for the purpose of separating manure and fermentation residues. The main focus was on the relief of the area through a high degree of separation of nutrients, such as phosphorus and the achievable biogas yield from separated pig manure. For this purpose, a comprehensive series of studies with scientific support was carried out. In the first step, manure with different settings was separated on an agricultural pig fattening farm with the aim of a maximum phosphorus separation. In addition, fermentation tests were carried out to determine the possible biogas yield of the separated phases and compare it with the raw manure.


  • A setting could be found that provided promising nutrient separation rates.
  • It could be shown that high dry matter contents in the solid phase only make limited sense, since the electricity consumption increases with the dry matter content, while the throughput decreases. The separation efficiencies for the nutrients phosphorus, potassium and nitrogen also decrease. By means of an optimum curve, sensible and optimum settings can be found for the use of the solid phase in the biogas plant.
  • 7 to 3 parts of separated pig manure can replace one part of silage maize.
  • The advantage of the Klass spiral filter is its flexibility and the associated good adaptability to the substrate to be separated. In addition, the Klass spiral filter provides impressive parameters for throughput and power consumption.

Products used