Membrane filter unit and method for the production of the membrane filter unit
The invention relates to a membrane filter unit for liquid or gaseous media, comprising a bundle of capillary membranes which are open on at least one front surface side and which are cast in an area which is close to the end of the open membrane ends, in a sealing layer forming a hardened head part. The open membrane ends protrude on the outer side of the sealing layer. The sealing layer is arranged on a spacer element which has a layer which is penetrated by the capillary membranes and which is non-permeable in relation to the casting material which hardens in order to form the sealing layer. The invention also relates to a method for the production of a membrane filter unit.
1. Method for the production of a membrane filter unit for liquid or gaseous media, the membrane filter unit having a plurality of capillary membranes open on at least one face, which are cast into a sealing layer that has hardened to form a solid head piece, in a region close to the end, with regard to the open membrane end, whereby the open membrane ends protrude on the outside of the sealing layer, wherein the sealing layer is disposed on a spacer that has a layer that is penetrated by the capillary membranes and is impermeable for the casting material that hardens to form the sealing layer,
whereby capillary membranes are inserted into the spacer with one protruding end, which spacer has a layer that is penetrated by the capillary membranes and is impermeable for casting material,
whereby a sealing layer of viscous casting material is applied to the spacer, which material fills the free space between the capillary membranes that protrude at the top of the spacer, up to a level below the membrane ends, and hardens to form a solid head piece,
whereby the spacer comprises a perforated plate in which the openings of the perforations are stretchable to insert the capillary membranes therethrough, and
whereby a capillary membrane is inserted through each of the perforation openings.
2. Method according to claim 1 , wherein the ends of the capillary membranes that protrude above the spacer remain unclosed during application of the casting material.
3. Method according to claim 1 , wherein the casting material is fed in at the top of the spacer, next to the capillary membranes.
4. Method according to claim 1 , wherein the casting material is fed in through one or more openings of a component that accommodates the casting material.
5. Method according to claim 1 , wherein the sealing layer is applied to the spacer in several layers, whereby the lower layer, in each instance, has hardened at least partially before the next layer is applied.