Patent ID: 7410581

Claim:
In a cross flow filtration system of a type used for carrying out reverse osmosis (RO), where such system comprises one or more treatment units each consisting of an elongate pressure vessel having a first end, a second end, a single feed inlet, at least a brine outlet, and at least two separate permanent permeate outlets such that all of the permeate produced by the system during normal operation is withdrawn from the system through the permanent permeate outlets, and also wherein the elongate pressure vessel contains a plurality of filter modules, at least two of which are interconnected in a string along an axis of said pressure vessel such that the filter modules feed a common permeate collection manifold that extends axially through the pressure vessel and through the interconnected filter modules contained within the pressure vessel whereby pressurized feed provided at the feed inlet permeates under pressure through said filter modules and into said permeate collection manifold which is in fluid communication with a permeate outlet, the improvement comprising: a treatment unit wherein a moveable flow divider in said permeate collection manifold disrupts the normal flow of permeate by establishing a fluidically separate manifold branch of the permeate collection manifold associated with each permanent permeate outlet, and further wherein said treatment unit is arranged such that at least one of said permanent permeate outlets receives permeate from at least two of said interconnected filter modules while all of the permeate produced by the system continues to be withdrawn from the system through the permanent permeate outlets.