Abstract: A process for separating solvent from a feed solution, said process comprising: contacting a feed solution comprising solutes dissolved in a solvent with one side of a nanofiltration membrane, applying hydraulic pressure to the feed solution, such that solvent and some of the dissolved salts from the feed solution flow through the nanofiltration membrane to provide a permeate solution on the permeate-side of the nanofiltration membrane and a concentrated solution on the retentate-side of the nanofiltration membrane; contacting the permeate solution from the nanofiltration membrane with one side of a reverse osmosis membrane and applying hydraulic pressure to the permeate solution, such that solvent from the permeate solution flows through the reverse osmosis membrane to leave a concentrated solution on the retentate-side of the reverse osmosis membrane, using the concentrated solution from the retentate-side of the reverse osmosis membrane as at least part of the feed solution to the nanofiltration membrane;

Abstract: A process for separating solvent from a feed solution, said process comprising: contacting a feed solution comprising solutes dissolved in a solvent with one side of a nanofiltration membrane, applying hydraulic pressure to the feed solution, such that solvent and some of the dissolved salts from the feed solution flow through the nanofiltration membrane to provide a permeate solution on the permeate-side of the nanofiltration membrane and a concentrated solution on the retentate-side of the nanofiltration membrane; contacting the permeate solution from the nanofiltration membrane with one side of a reverse osmosis membrane and applying hydraulic pressure to the permeate solution, such that solvent from the permeate solution flows through the reverse osmosis membrane to leave a concentrated solution on the retentate-side of the reverse osmosis membrane, using the concentrated solution from the retentate-side of the reverse osmosis membrane as at least part of the feed solution to the nanofiltration membrane;

Abstract: A process for separating solvent from a feed solution, said process comprising contacting the feed solution with one side of a semi-permeable membrane, applying hydraulic pressure to the feed solution, such that solvent from the feed solution flows through the membrane by reverse osmosis to provide a permeate solution on the permeate-side of the membrane, separating solvent from the permeate solution to provide a stream comprising the solvent and a residual solution having an increased osmotic pressure than the permeate solution, and recycling the residual solution to the permeate-side of the semi-permeable membrane, whereby the osmotic pressure on the permeate-side of the semi-permeable membrane is lower than the osmotic pressure of the feed solution.

Abstract: A process for separating solvent from a feed solution, said process comprising: contacting a feed solution comprising solutes dissolved in a solvent with one side of a nanofiltration membrane, applying hydraulic pressure to the feed solution, such that solvent and some of the dissolved salts from the feed solution flow through the nanofiltration membrane to provide a permeate solution on the permeate-side of the nanofiltration membrane and a concentrated solution on the retentate-side of the nanofiltration membrane; contacting the permeate solution from the nanofiltration membrane with one side of a reverse osmosis membrane and applying hydraulic pressure to the permeate solution, such that solvent from the permeate solution flows through the reverse osmosis membrane to leave a concentrated solution on the retentate-side of the reverse osmosis membrane, using the concentrated solution from the retentate-side of the reverse osmosis membrane as at least part of the feed solution tothe nanofiltration membrane;wi