Patent ID: 8759083

Claim:
A bioreactor for methanizing non-pumpable biomass having a high solids fraction, comprising: a gas-tight sealable and liquid-tight digestion tank, a biogas discharge conduit, a loading and unloading opening for filling and emptying the digestion tank with the non-pumpable biomass, a percolate drainage system in the base and/or the walls of the digestion tank, and a percolate control system connected to the percolate drainage system, the percolate control system comprises: a percolate storage, which is connected to the percolate drainage system by way of a percolate discharge conduit, a valve disposed in the percolate discharge conduit, and a percolate fill level sensor for determining the percolate liquid level in the digestion tank separately from the fill level of the non-pumpable biomass in the digestion tank, the percolate control system is configured to control a biogas generation rate by adjusting the percolate liquid level in the digestion tank.