Waste Water Treatment

Biological Processes for Industrial Waste Water

Biological processes used for the treatment of industrial waste water are either aerobic (in the presence of oxygen) or anaerobic (in the absence of oxygen). Anaerobic processes entail fermentation of organic content by microorganisms, producing energy-rich biogas. No energy is required for the air supply, and also very little excess sludge is produced. However, not all organic compounds can be treated anaerobically, which is why there is often a subsequent aerobic process.

Eisenmann offers customers a truly end-to-end solution for treating biological waste water, including the Pyrobustor® for the thermal treatment of sewage sludge.

Applications of Biological Processes for the Treatment of Industrial Waste Water

Outdoor biological treatment system for industrial waste waterCombined aerobic processes

The manufacture of TV tubes generates waste water contaminated with both organic and inorganic pollu-
tants. For this application, Eisenmann designed a plant with an aerobic biological process for treating the organic pollutants and a separate, physical-chemical precipitation stage for the inorganic contaminants.

For the aerobic stage, a membrane bioreactor (MBR) under aerobic conditions with high sludge age was used. This high-performance process produces minimum excess sludge. The waste water contaminated with inorganic compounds is pre-treated by flocculation and sedimentation and the pollutants subsequently removed by detoxification, followed by precipitation. They can then be directly discharged into the river via gravel filters


Anaerobic biological process with rotating disc filtersCombined anaerobic processes

In collaboration with the Fraunhofer Institute, Eisenmann has developed a process for the anaerobic treatment of waste water. The central element is an anaerobic MBR with an Eisenmann rotating filter which completely re-
moves the adapted microorganisms from the treated wa-
ter. As a result, a large proportion of the energy contained in the waste water in the form of organic compounds can be converted to biogas, with minimum excess sludge production. Ultrafiltration reclaims the phosphate and ammonium, which are dissolved in the solids-free clarified waste water, for use as fertilizers. Furthermore, the purified water can be reused in a variety of ways.