The main challenge of the proposed project is the development of a ceramic honeycomb nanofiltration membrane with strongly increased membrane area of up to 25 m². The strongly increased membrane area in comparison with existing ceramic membranes for nanofiltration in combination with a high surface to volume ratio shall be competitive with polymeric membranes in terms of economics. The nanofiltration coating will allow for instance the direct filtration of surface water for drinking water preparation by a “low volume, low energy” filtration process. The low fouling tendency of the ceramic material will lead to low operating costs and reduced membrane down time during membrane cleaning. The high mechanical stability enables high pressure back-flushing of the membranes. The high chemical and thermal stability of the membrane material allows the chemical or thermal regeneration and sterilization by aggressive chemicals or hot steam if needed. Furthermore ceramic membranes shows considerably higher permeate fluxes in comparison to polymeric membranes. In addition to the high permeability and a low fouling tendency the membranes can be operated at low transmembrane pressures and low cross flow velocities. This strategy helps to reduce operation costs and save energy (“low feed, low pressure”).The proposed project will address a crucial point in terms of a more extended use of membrane filtration technologies in water purification: the ratio between active filtration surface and module size. Besides overall ordinary requirements in membrane filtration like long term stability, appropriate membrane price, high selectivity, high flux/pressure ratio, low energy demand for cross-flow-filtration and low membrane cleaning frequency this parameter will be of vital importance for the implementation of ceramic membrane technique in a large scale.