Membrane bag and method of producing same

摘要

The present invention is related to a method of manufacturing a membrane bag, comprising the steps of: (i) providing a spacer fabric with a first (11) and a second (12) layer of fabric spaced apart and tied together by monofilament thread (15) and comprising first regions (42) and second regions (41) in which the fabric has a larger meshes than in the first regions, and wherein each of the first regions are delimited fully around by the second regions, (ii) coating the first and the second layer with a membrane dope (43) wherein, in the first regions, the dope at least partially embeds the first and the second layer and leaves a space (23) between the first layer and the second layer free from membrane dope and the dope fills the spacer fabric in the second regions (41,44) and (iii) forming the membrane. A membrane bag comprises a volume for permeate collection, and is characterised in that said volume is completely enclosed in membrane substance.