FI ELD OF THE I NVENTI ON

The invention generally relates to filtration membranes and their methods of manufacture.

BACKGROUND

Integrated permeate channel membranes have been disclosed in WO 2006 015 461 . The current invention envisages an alternative membrane and an alternative method of production. The resulting membrane can be used in assemblies used for (waste) water treatment.

SUMMARY OF THE I NVENTI ON

To such end, the invention provides a method according to claim 1 , and an integrated permeate channel membrane according to claim 12. Preferably, two fabric layers each provided with a plurality of anchor members are separately provided with membrane layers. Preferably at least a portion of the anchor members is positioned outside the membrane layer. Preferably anchor members of respective fabric layers facing each other may interact with each other (when sufficiently close), forming bonds. Separate fabric layers may thus first be provided with a membrane layer. Only subsequently, the fabric layers may be interconnected to form an I PC membrane. Optionally, two anchor members may only interact when facing each other. Optionally, two anchor members may only interact when at least one of both is first activated.

In further aspects, the invention provides a water filter module according to claim 14, and a use of the integrated permeate channel membrane according to claim 15.

DESCRI PTI ON OF FI GURES

Fig. 1 shows an embodiment of a fabric layer. Fig. 2 shows an embodiment of a fabric layer provided with anchor members. Fig. 3A shows an embodiment of a fabric layer provided with anchor members and a membrane layer, in cross-section. Fig. 3B-D show an embodiment of two such fabric layers. Fig. 3D shows an embodiment in which the fabric layers are interconnected to form an I PC membrane. Fig. 4A-E equally show embodiments of two fabric layers, according to several possible embodiments.

DETAI LED DESCRI PTI ON OF THE I NVENTI ON

The present invention concerns a method for manufacturing an I PC membrane, an I PC membrane, a water filter module, and the use of an I PC membrane.

Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

As used herein, the following terms have the following meanings:

“A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, “a compartment” refers to one or more than one compartment.

“About” as used herein referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of + /- 20% or less, preferably + /-10% or less, more preferably + /- 5% or less, even more preferably + /-1 % or less, and still more preferably + /-0.1 % or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed invention. Flowever, it is to be understood that the value to which the modifier “about” refers is itself also specifically disclosed.

“Comprise”, “comprising”, and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains” and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein. Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between sim ilar elem ents and not necessarily for describing a sequential or chronological order, unless specified. I t is to be understood that the terms so used are interchangeable under appropriate circumstances and that the em bodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein .

The recitation of num erical ranges by endpoints includes all num bers and fractions subsumed within that range, as well as the recited endpoints.

Unless otherwise defined, all terms used in disclosing the invention , including technical and scientific terms, have the m eaning as com monly understood by one of ordinary skill in the art to which this invention belongs. By m eans of further guidance, definitions for the terms used in the description are included to better appreciate the teaching of the present invention. The terms or definitions used herein are provided solely to aid in the understanding of the invention.

I n a first aspect, the invention concerns a m ethod for manufacturing an integrated perm eate channel m em brane, said m ethod com prising the steps of: providing a membrane layer to each of a first fabric layer and a second fabric layer, the fabric layers being at least partly embedded in the m em brane layers, and interconnecting said first and second fabric layers parallel to each other.

I n particular, both fabric layers are further provided with a plurality of anchor members, wherein the fabric layers are interconnected and spaced apart via anchor members of the respective fabric layers interacting with each other, form ing bonds.

Optionally, the application of the m embrane layer involves a coating of the fabric layers. Optionally, the fabric layers are coated at one side (the outer side) with the anchor m em bers (= the anchor points) out of the coated fabric layers at the opposite side (the inner side) . Optionally, on and over one single textile, a m em brane is cast that penetrates into the fabric and forms a m echanical anchorage with the fabric. This m em brane layer will leave the anchor points free extending for at least a certain distance. Preferably, at least a portion of the interconnecting members (i.e. the anchor members or anchor points) provided by the first fabric layer is interacting with at least a portion of the interconnecting members provided by the second fabric layer.

The anchor members of the two fabrics may or may not be the same. Anchor members provided by the first fabric may be of the first type, anchor members provided by the second fabric may be of a second type. Preferably, the anchor members of the first and second fabric are at least suitable for interacting or for supporting an interaction.

I n a further or alternative embodiment, said anchor members are distributed over at least an inner surface of the respective fabric layers. I n a further or alternative embodiment, said interconnecting step involves bringing the fabric layers together via their inner surfaces. I n a further or alternative embodiment, the anchor members are partly embedded in the respective membrane layers, and partly protrude from the membrane layers at said inner surfaces. I n a further or alternative embodiment, the anchor members are substantially orthogonal to the respective fabric layers. I n another embodiment, said anchor members are positioned under an angle to the respective fabric layers.

I n a further or alternative embodiment, said fabric layers comprise a woven or non- woven fabric. The textile may be a woven or non-woven textile that in the perpendicular direction has anchor points extending from the (non) woven textile surface at one side. The anchor points/members may or may not be partly formed by the textile. The anchor points/members may or may not be integrally formed by the textile. The textile material may be polyester, polypropylene, polyethylene or other weather and chemical resistant fiber. I n another or further embodiment, said textile material may include an amount of metallic fibers, composed of metal, metallic alloys, plastic-coated metal, metal-coated plastic, or fibers being covered by a metal layer. Suitable metals include silver, gold, alum inum , ...

I n another embodiment, said fabric layers are made of a 3D printed material wherein the anchor points are part of the 3D printed material or added afterwards.

Said fabric layers may be gamma irradiated to reduce the bioburden. Said fabric layers may have pores or openings. The pore size of said pores or openings is preferably comprised between...

I n a further or alternative embodiment, the respective anchor members each comprise an interaction portion by means of which said anchor members interact chem ically, physically and/or mechanically.

The bonding between the anchor points can be any chem ical bond: electrostatic, covalent, hydrogen bonding, van der Waals bonding or melted together, sealed by sealants as there are polyurethane, epoxy, methyl methacrylate or even UV or heat curing adhesives. I n particular, said interaction may comprise a chem ical bond (e.g. an electrostatic bond, a covalent bond, a hydrogen bond, a Van der Waals bond) . Additionally or alternatively, said interaction may comprise a physical bond (e.g. melted or glued together) . Additionally, said interaction may comprise a mechanical bond (e.g. via a hook-and-loop-type fastener) .

I n a possible embodiment, the bonding is strong enough to form a stable backflushable/backwashable/backpulsable I PC membrane sandwich with a back wash pressure resistance of > 150 mbar, preferably between 500 and 3000 mbar.

I n a further or alternative embodiment, said method further comprises the step of activating at least a part of said interaction portions chem ically, physically and/or mechanically. Activation may be performed selectively. That is, some of the anchor members are activated, but not all. Selective “activation” to the anchor points prior, during or after the membrane casting is part of this invention as well. Physical activation may for instance involve magnetizing at least a part of the interaction portions. Chemical activation may for instance involve exciting some of the substances present in the interaction portions. Activation (e.g. electrostatically charging or magnetizing some of the anchor members) may be performed prior, during, or after applying the membrane layers to the fabric layers.

I n a further or alternative embodiment, said interaction portions have an increased surface area. Said anchor members may have all sorts of shapes and forms suited to be used in the framework of the current invention. I n a further or alternative embodiment, said anchor members comprise a substantially T-shaped cross-section. I n a further or alternative embodiment, said interaction portions interact to form an interaction layer of increased density, interposed between first and second permeate channels. I n a second aspect, the invention concerns an integrated permeate channel membrane, comprising: first and second fabric layers, which fabric layers are mutually parallel layers that are interconnected and spaced apart, membrane layers provided to each of said fabric layers, the fabric layers being at least partially embedded in the membrane layers, and a permeate channel interposed between said two membrane layers.

I n particular, the fabric layers are each provided with a plurality of anchor members, wherein the fabric layers are interconnected and spaced apart via anchor members of the respective layers that interact or have interacted with each other, form ing bonds. Optionally, said integrated permeate channel membrane is obtainable via the method according to the first aspect of the invention. Method of first aspect is preferably suitable for manufacturing the integrated permeate channel membrane of the second aspects. Corresponding features and advantages may or may not apply.

I n a further aspect, the invention concerns a water filter module comprising a plurality of such integrated permeate channel membranes. Applications for the membranes according to the invention are numerous and include MBR, microfiltration, ultrafiltration, membrane distillation, pervaporation, vapour permeation, gas separation, supported liquid membranes and pertraction. I n a preferred aspect, the invention concerns the use of such integrated permeate channel membranes, for the treatment of (waste) water.

The invention is further described by the following non-limiting examples which further illustrate the invention, and are not intended to, nor should they be interpreted to, lim it the scope of the invention.

Fig. 1 shows an embodiment of a fabric layer. The fabric layer may comprise a woven or 3D printed textile. Fig. 2 shows an embodiment of a fabric layer provided with anchor members (i.e. anchor points). Fig. 3A shows an embodiment of a fabric layer provided with anchor members and a membrane layer, in cross-section. The membrane layer is casted on and over the textile. Fig. 3B shows how two these coated textiles with the anchor points directed to one another can be assembled. Fig. 3C shows how at least some of the anchor points will form a bond. I n Fig. 3D, a sandwich structure with an open integrated permeate channel (I PC) in the center is obtained.

Fig. 4A-E equally show embodiments of two fabric layers, according to several possible embodiments. The anchor points can have all sorts of shapes (including T shapes) and forms, can have a large density protruding through the textile (after coating) of the membrane surface. Densities can be as high as 100% in the center (that is, at the level of their interacting portions). Optionally, where an interaction layer of increased density up to 100% is formed by the interaction portions, two integrated permeate channels are formed at either side. See Fig. 4E. In all other cases one open permeate channel is formed.

The anchor points may be activated on one side (Fig. 4C) or on both sides (Fig. 4B) to form a bond. The figures further show an I PC sandwich structure with the anchor points that are bond together with a high anchored points density in the center (Fig. 4D) and with a 100% anchored points density in the center (Fig. 4E).

The purpose of the I PC structure is to be a permeable substrate, membrane which has a certain porosity and has pores from the micrometer range to the nanometer range.

The numbered elements on the figures are:

1 Fabric layer

2 Anchor member

2’ Activated anchor member

3 Membrane layer

4 Bond

5 Permeate channel

6 Interaction portion 6’ Activated interaction portion

7 I nteraction layer

The present invention is in no way limited to the embodiments described in the examples and/or shown in the figures.