Patent ID: 11890578
Assignee: THE UNIVERSITY OF BIRMINGHAM
Field: Chemical engineering (Chemistry)
Classification: CPC B  C  F  Y | IPC B  C  F

Claim 0:
1. A desalination system comprising:
a partitioned container housing a movable partition partitioning the container into an upstream compartment and a downstream compartment each of variable volume, the partitioned container having a first inlet port at an upstream end of the container, a second inlet port at a downstream end of the container and an outlet port at the downstream end of the container;
a membrane container housing a cross-flow semipermeable membrane dividing the membrane container into a saline compartment and a desalinated compartment, the saline compartment comprising first and second cross-flow ports, the desalinated compartment comprising a desalinated water outlet port;
a feed pump connected to feed a supply of saline water to the first inlet port;
a recharge pump having an inlet connected to the second cross-flow port and an outlet connected to the second inlet port to feed saline water into the downstream compartment;
a main valve connected between the outlet port and the first cross-flow port;
a bypass valve connected on one side to the inlet port and on another side to the second cross-flow port and the inlet of the recharge pump;
a purge valve connected on one side to the first cross-flow port and the main valve and on another side to a purge port; and
a controller connected and configured to operate the desalination system, the controller configured to:
in a first pressurisation stage, close the bypass valve and purge valve, open the main valve and operate the feed pump to provide a supply of saline water to the upstream compartment of the partitioned container, causing the partition to move and thereby flowing saline water from the downstream compartment into the saline compartment of the membrane container, thereby causing desalinated water to exit from the desalinated compartment of the membrane container via the desalinated water outlet port; and
in a second recharge stage, open the bypass valve and purge valve, close the main valve and operate the recharge pump and feed pump to feed saline water to the second inlet of the partitioned container and into the saline compartment of the membrane container via the second cross-flow port to cause saline water to flow out through the purge port via the first cross-flow port.