Patent ID: 8043512

Claim:
A fluid treatment arrangement comprising a core assembly having a longitudinal axis; a fluid treatment pack including a fluid treatment medium having a feed surface and an opposite permeate surface, a feed region extending along the feed surface of the fluid treatment medium, and a permeate region extending along the permeate surface of the fluid treatment medium, wherein the fluid treatment pack is spirally wound around the core assembly and includes a plurality of windings of the feed region, a plurality of windings of the permeate region, and a plurality of windings of the fluid treatment medium, each winding of the fluid treatment medium being positioned between a winding of the feed region and a winding of the permeate region, wherein the spirally wound fluid treatment pack has a plurality of axially adjacent sections, the feed region of one section fluidly communicating with the feed region of an adjacent section and the permeate region of the section being fluidly isolated from the permeate region of the adjacent section, and wherein each section of the spirally wound fluid treatment pack has a permeate port extending generally radially through the plurality of windings of the feed region, the plurality of windings of the fluid treatment medium, and the plurality of windings of the permeate region, each permeate port fluidly communicating with the windings of the permeate region and being fluidly isolated from the windings of the feed region; and one or more control mechanisms, a control mechanism being fluidly coupled to the permeate region of at least one section of the spirally wound fluid treatment pack to control a flow parameter in the permeate region of that section.