Fermenter and process for the continuous, anaerobic, biological degradation of waste waters

Fermenter for the continuous, anaerobic degradation of waste waters with the production of biogas, comprising a plurality of chambers situated one after the other (seen in the flow direction of the waste water through the fermenter), which chambers are filled with the liquid to be degraded, and the liquid level decreasing from chamber to chamber. The liquid flows, or is advantageously pumped, through all the chambers. Each chamber is furnished with supports, which are colonised by the anaerobic bacterial strains, and further devices. The supports are preferably plastic material, that is polyethylene terephthalate fibre material, which has advantageously been processed to form nets or the like. The clarified water is withdrawn after the last chamber. The biogas is likewise advantageously withdrawn in the vicinity of the outflow position of the clarified waste water. The advantages of the fermenter according to the invention and of the process according to the invention for waste water purification using this fermenter are: concentration gradient (decreasing in the direction of flow), plug flow, immobilisation, uniform gas solubility in the entire fermenter because of restricted height, improved ability to monitor the entire unit, since it is a multichamber system, has a high outgassing surface area, and can be operated at 35 DEG C or 50-70 DEG C.