Comparison of various membrane types and module configurations in the treatment of natural water by means of low-pressure membrane methods

For the treatment of potable water, membrane methods are being introduced currently, in particular microfiltration (MF) or ultrafiltration (UF). UF and MF membranes constitute an effective barrier for suspensions, bacteria, viruses and other microorganisms, and therefore they are taken into consideration as clarification and disinfection stages of water treatment within a single operation. There are other advantages involving the application of membrane techniques for water treatment, such as: production of water having invariable quality, much smaller quantities of chemical substances added in the process and lower consumption of energy. The paper presents the results of research investigations on the application of polymeric and ceramic MF and UF membranes of different configuration (flat, tubular-multichannel and capillary systems) for the removal of impurities from ground waters. Ultrafiltration polymeric flat membranes were made of polyacrylonitrile and polysulfone, whereas the capillary MF module was made of polypropylene (Euro-Sep, Warsaw). UF and MF ceramic membranes based on zirconium oxide were provided by the French firm Tech-Sep. The effectiveness of membrane water treatment has been evaluated based on the volume of water flux (permeate) as well as on microbiological and physicochemical analysis of raw water and permeate.