Abstract: A concentrated spent dialysate is produced for by reducing electrolytes in a spent dialysate by electrodialysis and de-watering the spent dialysate by a forward osmosis operation. A hemodialysis treatment apparatus has an ultrafiltration unit for exchange of solutes of a patient's blood plasma and a dialysate, resulting in a stream of cleaned blood for returning to the patient and a stream of spent dialysate. An electrodialysis device reduces electrolytes in the spent dialysate. A forward osmosis unit with a membrane having a feed side and a draw side that is allows only water to permeate. A stream of spent dialysate from the ultrafiltration unit is in fluid communication with the feed side and a stream of concentrated dialysate is in fluid communication with the draw side. A stream of dialysate results. Blood plasma is pumped from the patient to the ultrafiltration unit.

Abstract: A hollow fiber module includes hollow fiber cartridges. A port receives a second solution to be treated in a shell side volume and another port for discharging the treated second solution. A first end cap has an inlet for a first solution and a distributer for distributing the first solution to a first end of the hollow fiber cartridges. A second end cap has a collector for collecting the treated first solution from the second end of the hollow fiber cartridges and an outlet for the treated first solution. A first connector has an inlet for the second solution and a distributer for distributing the second solution to a port of the hollow fiber cartridges. A second connector has a collector for collecting the treated second solution from the other port of the hollow fiber cartridges and an outlet for the treated second solution.