METHODS FOR SUSTAINABLE MEMBRANE DISTILLATION CONCENTRATION OF HYPER SALINE STREAMS

摘要

A novel method of producing concentrated streams or otherwise useful hypersaline brines from a source of non-potable or otherwise impaired water is provided. The method comprises feeding the source water into the feed side of a membrane distillation unit while simultaneously feeding a distillate stream through the receiving side of the distillation unit. The feed and receiving sides are separated by a hydrophobic, microporous membrane that allows water vapor to flux through the membrane to the receiving side. As the membrane becomes clogged with particulates, the unit can be subjected to stream flow reversal and/or temperature gradient reversal in order to remove those particulates and restore previous vapor flux levels, after which previous operations can be resumed.

主权项

1. A method of concentrating water comprising:
(a) providing a membrane distillation unit comprising:
a feed side having an inlet and an outlet;a receiving side having an inlet and an outlet; and
a membrane positioned between the feed and receiving sides, said membrane being in communication with both said feed side and said receiving side; (b) passing:
a source water having a first temperature through either said feed side or said receiving side; anda distillate stream having a second temperature through the other of said feed side or said receiving side, said first temperature being higher than said second temperature, thereby creating a vapor pressure gradient across said membrane, causing a vapor flux from said source water to said distillate stream; and (c) carrying out one or more of the following:
(i) reversing said passing so that said source water having said first temperature and distillate stream having said second temperature pass through the sides other than from the sides through which they were passing prior to said reversing;(ii) ceasing the passing of said source water and causing a cooling stream to pass through the side through which the source water was passing prior to said ceasing, said cooling stream having a temperature that is lower than said distillate stream second temperature; and(iii) ceasing the passing of said distillate stream and causing a heated water stream to pass through the side through which the distillate stream was passing prior to said ceasing, said heated water stream having a temperature that is higher than said source water first temperature.