Wet screenings are fed into the hopper until the right amount of screenings has accumulated. If necessary, additional water is added through a valve placed on the side of the hopper. The agitator thereafter starts and helps break up organic matter with the help of created turbulence.

When the agitator stops, the gate valves on the drainage outlet of the press is opened and water is led out. Simultaneously, the transport screw in the press start and screenings are fed forward. If needed, additional wash water can be added through the wash system of the press.