Thin-Film Filtration of Difficult-to-Filter Suspensions Using Polymeric Membranes

Fine-grained particle systems build up a highly consolidated and thin layer on the filter medium and cause a high filter cake resistance. The objective of the novel thin-film filtration process is an effective mechanical separation of these particle systems using membranes on a vacuum drum filter. The mechanical stability of the membrane is evaluated since a roller is required for the cake discharge and the filtration performance is compared with that of a commonly used filter cloth. Analyses reveal that the surface porosity is the crucial factor for the mechanical stability of the membrane. Furthermore, the filter cloth shows a higher filter media resistance than the membrane. A significant increase in the specific dry mass throughput and a particle-free filtrate could be achieved.