Comparative study of different MF and UF membranes for drinking water production

To evaluate the performance of several different MF and UF membranes for the filtration of reservoir water for drinking water production, membrane performance in combination with powdered activated carbon was studied in comparative pilot tests. The tests showed that the dosing of powdered activated carbon into the feed water of the membranes had no significant effect on the hydraulic behaviour of the membranes. Hollow-fibre ultrafiltration membranes, with a filtration direction from the inside to the outside of the fibre, could be used, without problems, in a dead-end filtration mode with concentrations up to 15 mg/l of powdered activated carbon in the feed water. Ultrafiltration and microfiltration membranes showed a similar performance in removing microorganisms and turbidity fi om the water. All membranes tested, produced water of a high quality which met the German Standard for drinking water. Modules with damaged membranes were identified by particle counts and pressure hold tests. Parallel to the detected membrane failure, higher values of micro-organisms in the product water were observed, confirming the measured particle counts.