Patent ID: 8883008

Claim:
A dialyzer comprising: first and second circularly cylindrical dialyzation chambers, and an intermediate chamber interposed between said first and second dialyzation chambers, wherein, each of said dialyzation chambers has opposed first and second ends; said dialyzation chambers are disposed side by side; each of said dialyzation chambers contains a filter member that separates said dialyzation chamber into a blood compartment and a dialysate compartment, each of said compartments extending between said first and second ends; said filter member in said first chamber is made of a filter material for filtering out plasma water from blood; said filter member in said second dialyzation chamber is made of a filter material for passing dialysate from said dialysate compartment to said blood compartment; said first dialyzation chamber has, at said first end thereof, a blood inlet communicating with said blood compartment and a dialysate outlet communicating with said dialysate compartment; said second dialyzation chamber has, at said first end thereof, a blood outlet communicating with said blood compartment and a dialysate inlet communicating with said dialysate compartment; said intermediate chamber extends between said second end of said first dialyzation chamber and said second end of said second dialyzation chamber and communicates only with said blood compartments during operation of said dialyzer to perform blood dialysis; said blood and dialysate inlets and outlets are located to produce dialysate flows in counter-current to blood flows in both of said dialyzation chambers; and said first and second dialyzation chambers are constructed to provide a dialysate flow path between said dialysate compartments at said second ends of said chambers, said dialysate flow path forming a constricted passage for dialysate that produces a dialysate pressure drop between said second dialyzation chamber and said first dialyzation chamber, wherein, for performing dialysis, the only connections to said dialyzer consist of said blood inlet, said blood outlet, said dialysate inlet and said dialysate outlet; and wherein blood has a direction of flow in each of said blood compartments and said constricted passage is oriented to provide a flow path that forms and acute angle with the direction of blood flow in each of said blood compartments.