Fluid treatment arrangements and methods of making fluid treatment arrangements

A fluid treatment arrangement comprising:

• first and second end pieces, the first end piece having a first surface comprising a thermoplastic;
• a fluid treatment unit positioned between the first and second end pieces, wherein the fluid treatment unit has a multilayer structure which includes a feed layer, a permeate layer, and a layer of permeable medium positioned between the feed layer and the permeate layer, the permeable medium having a feed side fluidly communicating with the feed layer and a permeate side fluidly communicating with the permeate layer, wherein the fluid treatment unit further has first and second opposite end surfaces and a thermoset which holds the layers of the multilayer structure together and which forms at least a portion of the first end surface of the fluid treatment unit;
• and
• a thermoplastic sheet overlying the first end surface of the fluid treatment unit and having first and second opposite surfaces, the thermoset directly bonding to the first surface of the thermoplastic sheet on the first end surface of the fluid treatment unit and the second surface of the thermoplastic sheet being bonded to the first thermoplastic surface of the first end piece.

A fluid treatment arrangement comprising:

• first and second end pieces;
• first and second fluid treatment units positioned between the end pieces, wherein each fluid treatment unit has a multilayer structure which includes a feed layer, a permeate layer, and a layer of permeable material positioned between the feed layer and the permeate layer, the permeable medium having a feed side fluidly communicating with the feed layer and a permeate side fluidly communicating with the permeate layer, each fluid treatment unit further having first and second opposite end surfaces and a thermoset which holds the layers of the multilayer structure together and which forms at least a portion of the first end surface of the fluid treatment unit;
• and
• first and second thermoplastic sheets positioned between the first end surfaces of the first and second fluid treatment units, each thermoplastic sheet having first and second opposite surfaces, the thermoset on the first end surface of the first fluid treatment unit directly bonding to the first surface of the first thermoplastic sheet, the thermoset on the first end surface of the second fluid treatment unit directly bonding to the first surface of the second thermoplastic sheet, and the second surfaces of the first and second thermoplastic sheets being bonded to one another.

A method of making a fluid treatment arrangement comprising:

• modifying at least a first surface of a thermoplastic sheet to enhance a bond between a thermoset and the first surface of the thermoplastic sheet;
• forming a fluid treatment unit having a multilayer structure including a feed layer, a permeate layer, and a layer of permeable medium positioned between the feed layer and the permeate layer with a feed side of the permeable medium fluidly communicating with the feed layer and a permeate side of the permeable medium fluidly communicating with the permeate layer, wherein forming the fluid treatment unit includes applying a thermoset to one or more of the feed layer, the permeable medium layer, and the permeate layer;
• and
• directly bonding the thermoset on a first end surface of the fluid treatment unit to the modified first surface of the thermoplastic sheet.