Biological Processes for Industrial Waste Water
Combined aerobic processes
The manufacture of TV tubes generates waste water contaminated with both organic and inorganic pollutants. 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.
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 removes the adapted microorganisms from the treated water. 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.