Water treatment assembly including hyperfiltration module and pressurizable reservoir

1. A water treatment assembly comprising a spiral wound hyperfiltration membrane module connected to:

i) a feed line adapted for connection to a source of pressurized feed water,

ii) a permeate line adapted for connection to a dispenser of treated water and

iii) a concentrate line adapted for connection with a drain and including a flow restrictor wherein the flow restrictor and spiral wound hyperfiltration membrane module are selected to provide more than 50% recovery when operated at 20 gfd with 500 ppm NaHCO 3 at 25° C. and a pH 8; and

iv) a pressurizable reservoir including valves for selectively diverting flow along the feed line, through the pressurizable reservoir and returning to the feed line prior to passing through the spiral wound hyperfiltration membrane module; and wherein the pressurizable reservoir comprises:

a) re-sealable opening by which an additive may be introduced,

b) an inlet and an outlet for pressurized feed water, and

c) a path through the pressurizable reservoir that has a length between the inlet and the outlet, and wherein the length exceeds five times the path's largest open diameter.

2. The assembly of claim 1 wherein the length between the inlet and the outlet exceeds ten times the largest open diameter of the pressurizable reservoir.

3. The assembly of claim 1 wherein the pressurizable reservoir contains a cleaning agent that is an acid.

4. The assembly of claim 3 wherein the pressurizable reservoir contains vinegar.

5. The assembly of claim 1 wherein the flow restrictor is a tube of at least 0.5 m in length having a minimum diameter of at least 1 mm.

6. The assembly of claim 1 further comprising a conductivity sensor located along the concentrate line adapted to detect a change in conductivity.

7. The assembly of claim 1 further characterized by excluding pumps and storage tanks for storing treated water.