Integrated Wastewater Treatment Process using Mesh Filter Modules for Direct Activated Sludge Separation
Abstract
The challenges of removing contaminations from wastewater with maximum reliability and efficiency by using wastewater treatment processes, plants and systems are growing, offering good opportunities for new and advanced technologies. One such innovative wastewater treatment system is the membrane bioreactor, an activated sludge process, where the secondary settling tank is substituted by a membrane filtration unit. The main advantages are high sludge concentrations and an excellent effluent quality. The driving force for the application of membrane bioreactors is a small area requirement combined with effluent disinfection. Membrane bioreactors become a highly attractive system where stringent standards have to be met, e.g. for discharge in bathing water or for water reuse. However, membrane bioreactors still need further improvement for a wider spread application. The main hindrances are high investments for membrane modules and high costs for membrane replacement and high operation costs due to increased energy demand. The innovation of this project is to overcome these drawbacks by the substitution of membranes by a cheaper filtration technique, offering higher flux rates at lower filter pressures. As activated sludge appears in form of flocs, a coarser filter material can be used to separate activated sludge from treated wastewater. The retention of sludge flocs leads to the formation of a secondary layer on the mesh surface, which serves as the actual filter membrane. By this means, even smaller particles than suggested by the mesh size are retained. Because of its high pore size, the filter mesh resembles almost no filter resistance. Another principal problem of membranes is fouling. Persistent deposits can only be removed by intensive periodical cleaning with chemical agents. In the MESH system, the secondary layer is periodically removed and a fresh layer is built up. Thus, the problem of fouling can be largely avoided and less frequent and intensive cleaning is necessary. The expected advantages can be summarized as follows: Cheap filter material, high flux rates, low filter resistance and hence trans filter pressure, low cleaning effort. In summary this results in: High effluent quality and plant reliability at low investments and low operational costs.
Membranes Cloth filtration
Publikationen
Project staff
Werner Fuchs
Ao.Univ.Prof. Dipl.-Ing. Dr.nat.techn. Werner Fuchs
werner.fuchs@boku.ac.at
Tel: +43 1 47654-97401, 97423
Project Leader
15.07.2006 - 31.10.2008
BOKU partners
External partners
EnviCare Engineering GmbH
Dr. Bernhard Mayr
partner
Glogar Environmental Technologies
Werner Vatier
partner
Aquaplus CZ
Klara Rothscheinova
partner
Institute of Chemical Technology Prague
Prof. Pavel Hasal, Department of Chemical Engineering
partner
MEMOS Membranes Modules Systems GmbH
Dr. Berthold Günder
partner
SIDER ARC Spa
Eng. Barbara Fontana
partner
SAATI SPA
Dr. Paolo Fracas
partner
University of Milano-Bicocca
Prof. Claudia Riccardi, Dipartimento di Fisica G. Occhialini - Centro di Eccellenza PlasmaPrometeo
partner