OSMOTIC SEPARATION SYSTEMS AND METHODS

摘要

Separation processes using osmotically driven membrane systems are disclosed generally involving the extraction of solvent from a first solution to concentrate solute by using a second concentrated solution to draw the solvent from the first solution across a semi-permeable membrane.

主权项

1. A system for osmotic extraction of a solvent from a first solution, comprising:
a forward osmosis unit comprising:
a first chamber having an inlet fluidly coupled to a source of the first solution;a second chamber having an inlet fluidly coupled to a source of a concentrated draw solution; anda semi-permeable membrane system separating the first chamber from the second chamber and configured for osmotically separating the solvent from the first solution, thereby forming a second solution in the first chamber and a dilute draw solution in the second chamber; a reverse osmosis unit fluidly coupled to an outlet of the second chamber of the forward osmosis unit and comprising:
a first chamber in fluid communication with the second chamber of the forward osmosis unit and configured for receiving the dilute draw solution under pressure;a semi-permeable membrane coupled to the first chamber; anda second chamber coupled to the semi-permeable membrane and configured for receiving a solvent fluxed through the membrane, thereby leaving a less dilute draw solution in the first chamber of the reverse osmosis unit; and a separation system in fluid communication with the forward osmosis unit and the reverse osmosis unit and configured to separate the dilute or less dilute draw solution into the concentrated draw solution and a solvent stream, the separation system comprising:
an inlet fluidly coupled to an outlet of the first chamber of the reverse osmosis unit for receiving the less dilute draw solution therefrom; andan outlet fluidly coupled to the second chamber of the forward osmosis unit for introducing the concentrated draw solution to the forward osmosis unit.