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.

This disclosure concerns a method of forming a covalent organic framework (COF) membrane, comprising forming a membrane substrate by impregnating a porous polymer with a pore-forming agent in order to form an impregnated polymer, at least partially carbonising the impregnated polymer at a temperature of about 150 C. to about 500 C. in order to form the membrane substrate, and interfacially polymerising amino monomers and acyl monomers on a surface of the membrane substrate in order to form the COF membrane. The membrane substrate is characterised by a crystallinity of about 10% to about 70% relative to the porous polymer. The disclosure also concerns the COF membrane thereof, and the use of the COF membrane in catalyst recovery.

A method and apparatus for treating a water including suspended solids and organics, the method including the method including providing a process stream including suspended solids and organics; adding a predetermined amount of at least one coagulant including at least one of a cationic polymer and nonionic polymer to the process stream to cause coagulation of contaminants including suspended solids and organics; passing the process stream with the coagulant downstream to at least one submicron filtration unit including at least one filter configured to filter particle sizes of about 1 micron or less; filtering the process stream with the at least one submicron filtration unit; and, separating a filtered and unfiltered portion of the process stream from the at least one submicron filtration unit to pass downstream respectively in a filtered and an unfiltered process stream.

An apparatus for reducing the ratio of divalent ions to a monovalent ion in an aqueous solution from a source aqueous solution that contains a higher ratio of divalent ions to the target monovalent ion. The apparatus includes an optional prefiltration portion operable to receive the source aqueous solution and produce a prefiltered aqueous solution, a first separation portion, such as a nanofiltration separation portion, operable to receive the optionally prefiltered aqueous solution and form an intermediate aqueous solution having a lower ratio of divalent ions to the target monovalent ion than the prefiltered aqueous solution; and a second separation portion, such as an ion-exchange separation portion, operable to receive the intermediate aqueous solution and form a product aqueous solution having a lower ratio of the divalent ions to the target monovalent ion than the intermediate solution.

Integrated, sequential stages of nanofiltration, forward osmosis, and reverse osmosis and related membranes provide an Integrated Osmosis structure, systems and methods. By optimally placing and using the desired characteristics of each membrane, performance and cost effectiveness not attainable individually is obtained. Integrated Osmosis systems provide high diffusive and osmotic permeability, high rejection, low power consumption, high mass transfer, and favorable Peclet number, by manipulating convection, advection and diffusion, low concentration polarization gradients, low reverse salt flux and effective restoration of performance after cleaning fouled membranes. Benefits include increased permeate recovery and decreased waste concentrate volume from reverse osmosis processes or other elevated osmotic pressure solutions. Integrated Osmosis first employs nanofiltration for selective harvesting of solutes, proffering a reduced osmotic pressure permeate. Forward osmosis dewaters the lowered osmotic pressure permeate generating a dilute draw solution which serves as feed to a reverse osmosis process. Reverse osmosis permeate provides freshwater and concentrate provides draw solution for the forward osmosis process.

Embodiments of the present disclosure provide for systems for removing contaminants from a leachate, methods of removing contaminants from a leachate, and the like.

Embodiments of the present disclosure provide for systems for removing contaminants from a leachate, methods of removing contaminants from a leachate, and the like.

A brine management system and method. The system includes one or more nanofiltration (NF) stages and one or more reverse osmosis (RO) stages. The one or more NF stages are configured to perform a diafiltration process. Each of the one or more NF stages is configured to process a NF feed and produce a NF permeate and a NF retentate. The one or more NF stages cooperatively produces a first brine output of the system. Each of the one or more RO stages is configured to process an RO feed and produce an RO permeate and an RO retentate. At least a part of the RO retentate forms a second brine output of the system. The RO feed to each of the one or more RO stages is exclusively formed from the one or more NF permeate from all of the one or more NF stages.

The present disclosure is directed to a process. In an embodiment, the process includes providing a boric acid solution composed of from 10 wt % to 25 wt % boric acid at a temperature from 60 C. to less than 100 C. to form a heated boric acid solution. The process includes first passing the heated boric acid solution through a first nanofiltration membrane at a pressure from 300 psi to 500 psi to form a first heated boron permeate and second passing the first heated boron permeate through a second nanofiltration membrane at a pressure from 300 psi to 500 psi and forming a second heated boron permeate. The second heated boron permeate is composed of at least 10 wt % boric acid, less than 5 ppm sodium, and less than 5 ppm of a component selected from calcium, lithium, sulfur, and silicon.

A method of treating biomass and ammonia-containing wastewater comprises anaerobically digesting the wastewater to produce a digestate, oxidizing dissolved sulfides in the digestate, mixing the digestate to form a mixed liquid, filtering the mixed liquid to produce a first filtrate, removing ammonia from the first filtrate to produce an ammonia-depleted filtrate, removing organic contaminants and divalent ions from the ammonia-depleted filtrate by nanofiltration to produce an organic-containing second retentate and an organic-depleted second filtrate, removing additional organic contaminants from the organic-containing second retentate by a second nanofiltration operation to produce a third filtrate and a third retentate, removing inorganic ionic species from the organic-depleted second filtrate by reverse osmosis to produce a fourth filtrate and a fourth retentate, combining the third filtrate and the fourth retentate, and removing additional inorganic ionic species from the combined third filtrate and fourth retentate by a second reverse osmosis operation.