Osmotic separation systems and methods
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. Enhanced efficiency may result from using low grade waste heat from industrial or commercial sources. Pre-treatment and post-treatment may also enhance the osmotically driven membrane processes.
1. A system for the processing of a solution using osmosis, the system comprising:
a forward osmosis module comprising:
a first chamber in fluid communication with a source of a first solution comprising a solvent and at least one solute;
a second chamber in fluid communication with a concentrated draw solution; and
a semi-permeable membrane coupling the first chamber and the second chamber; and
means for introducing a plurality of seeds into the first chamber, wherein the plurality of seeds cause nucleation of at least a portion of the at least one solute when the first solution is introduced into the first chamber.
2. The system of claim 1 further comprising a separation module in fluid communication with the second chamber for recovering at least one of a solvent stream and draw solutes.
3. The system of claim 2 further comprising means for recycling draw solutes into the concentrated draw solution.
4. The system of claim 1 further comprising a recovery module in fluid communication with the first chamber for recovering precipitated solutes.
5. An apparatus for the treatment of a solution using osmosis comprising:
a chamber configured for receiving a first solution comprising a solvent and at least one solute;
a membrane module disposed within the chamber and comprising a semi-permeable membrane having an exterior surface in fluid communication with the first solution and an interior surface for receiving a concentrated draw solution; and
means for introducing a plurality of seeds into the chamber, wherein the plurality of seeds cause nucleation of at least a portion of the at least one solute in the first solution in the chamber.