40 results about "Pressure-retarded osmosis" patented technology

A thin film composite or TFC membrane formed by interfacial polymerization of an organic and aqueous phase on a support membrane with nanoparticles in the discrimination layer and/or the support membrane, optimized by the selection of nanoparticles for membrane flux, hydrophilicity and to minimize thickness of the support membrane while maintaining the strength and ruggedness characteristics required for forward osmosis (FO) and/or pressure retarded osmosis (PRO) so that the flux flow paths are less tortuous than conventional support membranes and thereby provide increased flux flow.

An apparatus for osmotic power generation and desalination of seawater using a salinity difference is provided.

The apparatus for osmotic power generation and desalination using a salinity difference includes: a first osmotic membrane reactor having a first salt water position space and a third salt water position space separated by a first forward osmotic membrane; a second osmotic membrane reactor having a second salt water position space and a draw solution position space separated by a second forward osmotic membrane; a high pressure pump connected between the second salt water position space and the third salt water position space and supplying salt water which has passed through the second salt water position space to the third salt water position space and pressurizing salt water, which has passed through the second salt water position space, to supply it to the third salt water position space such that pressure retarded osmosis can be made in the first osmotic membrane reactor; a desalination unit obtaining fresh water by separating a draw solute from a draw solution diluted through a transmission of water in salt water of the second salt water position space by way of the draw solution position space; and a turbine driven by flow force of salt water discharged from the third salt water position space to produce electric energy.

A method of converting thermal energy into mechanical work that uses a semi-permeable membrane to convert osmotic pressure into electrical power. A closed cycle pressure-retarded osmosis (PRO) process known as an osmotic heat engine (OHE) uses a concentrated ammonia-carbon dioxide draw solution to create high osmotic pressures which generate water flux through a semi-permeable membrane against a hydraulic pressure gradient. The depressurization of the increased draw solution volume in a turbine produces electrical power. The process is maintained in steady state operation through the separation of the diluted draw solution into a re-concentrated draw solution and deionized water working fluid, both for reuse in the osmotic heat engine.

The invention provides a brine concentration method for sea salt production and belongs to the technical field of sea salt production. The method comprises steps as follows: seawater enters a pretreatment device for removal of impurities and enters a nanofiltration device for removal of divalent ions, nanofiltration producing water enters a multi-stage high-pressure reverse osmosis device for highconcentration, and high-concentration saline water is prepared; part of high-pressure reverse osmosis producing water is subjected to low-pressure reverse osmosis for preparation of pure water, and the other part of water flows back to a seawater desalting plant. The multi-stage high-pressure reverse osmosis device is formed through series connection of high-pressure reverse osmosis membrane groups in a form of continuous section groups, producing water of each section of the high-pressure reverse osmosis membrane groups flows back for use or enters a pure water preparation process, concentrated water of each section of the high-pressure reverse osmosis membrane groups enters the downstream high-pressure reverse osmosis membrane groups, the purpose of high concentration is finally achieved through continuous series connection, and strong brine is prepared. According to the method, more efficient concentration is realized, factory brine preparation is realized, the tedding area for salt making is greatly reduced, graded reuse of producing water is realized, utilization efficiency of the producing water is improved, and treatment cost is reduced.

The invention provides a method for treating desulfurization wastewater in a power plant. The method comprises the following steps: pretreating the desulfurization wastewater to obtain primary clarified liquor; enabling the primary clarified liquor to enter a filtering device to be filtered; providing a four-compartment electrodialyzer to perform ion recombination on ions in each water flow channel unit through an electric drive effect; further enabling produced water of each water flow channel unit to pass through a nanofiltration system to perform salt separation treatment, concentrating by utilizing an electrodialysis system, and desalinating the wastewater by utilizing a reverse osmosis system. According to the method disclosed by the invention, salts in the wastewater which are easy to scale are subjected to ion recombination so as to form soluble salts which are difficult to scale, so that the problem of scale formation in subsequent electrodialysis equipment or a high-pressure reverse osmosis system is solved. Moreover, according to the nanofiltration system for concentration, the electrodialysis system or the high-pressure reverse osmosis system, the content of total soluble solids in the wastewater is 8-16%, and the recovery rate of 80-90% of the wastewater is realized.

The invention discloses a reinforced hollow fiber composite membrane and a preparation method thereof.The preparation method is characterized in that hollow fiber ultrafiltration membrane yarn with an inner separation layer is prepared with a wet spinning process, filaments are adopted for knitting or crocheting on the outer surface of the hollow fiber membrane yarn, and a reinforced hollow fiber base membrane is obtained; a polyamide desalted layer is composited in an inner cavity of a fiber tube with an interfacial polymerization method, and the reinforced hollow fiber composite membrane is obtained.Higher mechanical strength of the membrane yarn is achieved with a netted support, and thus the reinforced hollow fiber composite membrane is suitable for the reverse osmosis and pressure-retarded osmosis processes performed at high pressure.

The invention discloses an electroplating wastewater reverse osmosis membrane treatment method adopting an energy recovery device. Key points of the technical scheme are that: the method comprises the following steps that: electroplating wastewater sequentially passes through an ultrafiltration membrane filtering raw water tank, an ultrafiltration membrane filtering delivery pump, an ultrafiltration membrane filtering unit, a reverse osmosis raw water tank, a booster pump and a security filter, and is divided; one branch enters a reverse osmosis device after being boosted by a high pressure pump, wherein the energy recovery device for recovering the energy of high-pressure reverse osmosis concentrated water flowing out of the reverse osmosis device is connected to the reverse osmosis device; and the other branch enters the reverse osmosis device through a circulating pump after the energy is recovered by the energy recovery device, filtered water filtered by the reverse osmosis device flows into a reverse osmosis product water tank, and after filtration, the concentrated water is treated and discharged.

The invention discloses a sea water desalination device based on pressure retardation osmosis and reverse osmosis and a method thereof. The sea water desalination device comprises a concentration difference power unit, a sea water desalination unit and a pressure transfer element positioned between the concentration difference power unit and the sea water desalination unit. The concentration difference power unit comprises a hollow seal water chamber No. 1, a hollow concentrated seawater chamber adjacent to the hollow seal water chamber No. 1, and an osmotic membrane positioned between the hollow seal water chamber No. 1 and the hollow concentrated seawater chamber, and the concentration difference power unit is used for converting salinity gradient power of sea water with different concentrations into static pressure. The sea water desalination unit comprises a hollow seal water chamber No. 2, a hollow fresh water chamber adjacent to the hollow seal water chamber No. 2, and a reverse osmosis membrane positioned between the hollow seal water chamber No. 2 and the hollow fresh water chamber, and under the effect of static pressure, the reverse osmosis membrane only allows water molecules to pass through, thereby achieving sea water desalination. The pressure transfer element can move or deform, and transfers static pressure to the seal water chamber No.2 through self moving or deforming. The device has a compact structure, only uses seawater salinity gradient energy for sea water desalination, does not consume high-grade energy and is green and environmental-friendly.

Natural water evaporation is a buffered process with huge energy absorption from solar & its derivative wind energy. When large surface shallow pool filled with aqueous solution is exposed under sky, the most portion of natural energy will be spent for pulling water out of water molecules cluster, yet there is still some energy for splitting water from solutes, then the concentration increases, in turn, despite the main former energy is sacrificed, but the stronger solution can redeem most the latter energy during a process of Pressure Retarded Osmosis (PRO), via membranes separating solution & available water in situ, then the redeemed energy serves as utilizable power output, with the assistance of key units or components: the osmotic to hydraulic pressure transformer, the hydraulic oil current rectification fluidic circuit & a hydraulic motor. With minor adaptation, same mechanism can also be embodied as: mobile osmosis engine, osmosis vehicle battery, yard synergy-osmosis power system, Grid electricity and miscellaneous renewable energy to osmosis energy storage, even desert to oasis remediation with seawater intake solar-via-osmosis powerplant & parasitic freshwater factory.

The invention provides a comprehensive process method for salt production by seawater desalination and belongs to the technical field of seawater treatment. The process method comprises the followingsteps: enabling pre-treated seawater to be subjected to reverse osmosis treatment, entering a nano-filtration device after reverse osmosis concentrated water is subjected to bromine extraction and pHregulation and is added with a reducing agent, performing salt production with nano-filtration concentrated water, and enabling concentrated water obtained by the treatment of nano-filtration producedwater with a high-pressure reverse osmosis device to enter an electrodialysis device so as to obtain strong brine and performing salt production with the strong brine through a mechanical steam recompression device. By utilizing a series of technologies such as nano-filtration, high-pressure reverse osmosis, electrodialysis, a mechanical steam recompression technology, a closed circulating loop is formed through dosage, concentration and graded reuse, and further, salt production, bromine extraction, magnesium extraction, mirabilite production and the like are performed, so that the comprehensive utilization of the seawater is realized.

The invention relates to an ultrathin-film composite membrane based on a thermally rearranged poly(benzoxazole-imide) copolymer and a production method therefor and to a technique for forming a poroussupport by means of a thermally rearranged poly(benzoxazole-imide) copolymer and then producing, on the porous support, an ultrathin-film composite membrane comprising a thin-film active layer. The ultrathin-film composite membrane produced according to the invention has excellent thermal/chemical stability and mechanical physical properties, thus is not only capable of withstanding high operating pressure, but also capable of minimizing internal concentration polarization and thereby obtaining high water permeability and, as a result, high power density, and thus can be applied to a pressure-retarded osmosis or forward osmosis process. Further, said ultrathin-film composite membrane has excellent chemical/thermal stability against organic solvents, has superior organic solvent nanofiltration performance, particularly maintains nanofiltration performance stably even under a high-temperature organic solvent condition, and thus can be applied as an organic solvent nanofiltration membrane.

Provided are thin film composite membrane structures comprising: a selective membrane layer for ion rejection attached to a support layer, the support layer comprising a multi-zone microfiltration membrane comprising: a porous support material; and at least two microfiltration zones, where a first zone comprises a first membrane and a second zone that is attached to the first zone and that coats at least a portion of the porous support material. Thin film composite membrane structures may be provided in reverse osmosis systems or nanofiltration systems. Also, thin film composite membrane structures may be provided in direct osmotic concentration systems, forward osmosis systems, or pressure retarded osmosis systems.

Spiral wound membrane rolls and modules and methods for making such membrane rolls and modules are described, along with water extraction or water filtrations systems comprising the spiral wound membrane rolls and modules and the use thereof in a forward osmosis process, an assisted forward osmosis process or a pressure retarded osmosis process.

A method of operating a pressure-retarded osmosis plant, the plant comprising at least one osmosis element having a semi-permeable membrane, the semi-permeable membrane defining a feed side and a permeate side of the osmosis element, the method comprising, in a first mode of operation, supplying a feed stream having a relatively high concentration of solute to the feed side, supplying a permeate stream having a relatively low concentration of solute to an inlet of the permeate side, and receiving a feed outlet stream from the feed side wherein permeate has passed through the semi-permeable membrane from the permeate side to the feed side, in a second mode of operation, supplying a backwash stream having a relatively low concentration to the feed side of the osmosis element such that water passes through the semi-permeable membrane, and receiving a permeate outlet stream from an outlet of the permeate side, the method further comprising alternately performing the first mode of operation, to perform a production step, and performing the second mode of operation, to reduce fouling of the semi-permeable membrane.

The invention discloses a method and a device for removing pollutants in water by freezing precipitation and pressure reverse osmosis. On the basis of a freezing purification principle and a pressurereverse osmosis principle of precipitating the pollutants by water freezing in the sewage freezing process, proper freezing temperature is selected and proper freezing rate is controlled by adopting atop-bottom one-way freezing mode according to the freezing precipitation characteristic of the pollutants; the pollutants are gradually removed by freezing from top to bottom, and finally bottom residual high-concentration pollutants are centrally and chemically treated, so that adverse influence of high cost, secondary pollution hazards and the like of a current chemical treatment mode is avoided. The technology fully utilizes the function of precipitating impurities by water freezing and phase change, and cooling energy only needs to be inputted into a solution. The method and the device have the advantages of high purification degree, no pollution, simplicity and convenience in operation, high cost performance and the like.

Provided are a porous outflow pipe and an osmosis module comprising same. A porous outflow pipe for forward osmosis or pressure-retarded osmosis, according to one embodiment of the present invention, comprises: a hollow pipe provided with a plurality of first through-holes and second through-holes in the lengthwise direction through which a fluid flows in and out; a bypass pipe arranged concentrically inside the hollow pipe in the lengthwise direction; and a partitioning plate formed along the circumference of the bypass pipe, for preventing mixing of a fluid introduced through the front end side of the hollow pipe and a fluid introduced through the second through-holes.

The invention belongs to the field of osmotic power generation equipment, and specifically discloses a pressure-delayed osmotic power generation system, aiming to solve the problems of large pressure fluctuations and high energy consumption of the existing PRO power generation system. The pressure-delayed osmotic power generation system includes an osmosis device, a dilute solution pool, a concentration device and a power generation device, and also includes a voltage stabilizing device and a water storage device. The water storage device can be used to store concentrated solution and recover pressure energy. By installing the pressure stabilizing device of the present invention between the concentrated solution side and the water storage device, not only can the system pressure be kept stable during the power generation process, but also system pressure fluctuations can be reduced. , and it is beneficial to achieve and maintain the optimal back pressure in the power generation system, which can reduce the use of stabilizing pumps and booster pumps in the power generation system, significantly reduce the system's own energy consumption, and thus increase the power generation of the system.

The invention relates to a method for preparing a pressure retarded osmosis membrane modified by a zwitterionic random copolymer. The method comprises the steps that methyl-2-[methyl-(4-pyridine)dithiocarbonate]propionate is used as a chain transfer agent, azobisisobutyronitrile is used as an initiator, N-vinylimidazole and an N-vinylphthalimide monomer containing an amino protecting group are subjected to random copolymerization; a poly N-vinylimidazole chain segment is subjected to quaternization under the action of propane sultone and 4-bromobutyric acid separately; under the action of hydrazine hydrate, a poly(N-vinylphthalimide)chain segment is subjected to amino deprotection to obtain a zwitterionic polymer; and the zwitterionic polymer is prepared into an aqueous solution to be grafted and modified on a porous support layer of an osmosis composite membrane. A comonomer used in the method is simple and easy to obtain, the random copolymer is convenient to synthesize, the condition is mild, and realization is easy; the chemical stability and water solubility of a graft polymer are improved, and the cost is greatly reduced; and excellent anti-protein and microbial adhesion areachieved.