KR20160137483A - See water desalination system using pressure-retarded osmosis - Google Patents

Abstract

The present invention relates to a seawater desalination system using a pressure-retarded osmosis (PRO) technique. Specifically, the seawater desalination system using a pressure-retarded osmosis technique according to an embodiment of the present invention comprises: a first pressure exchange apparatus and a second pressure exchange apparatus for increasing the pressure by receiving seawater; an SWRO facility for producing generated water in which salt is filtered via a reverse osmosis membrane by receiving the seawater with the increased pressure, and for transmitting the concentrated salt water to the second pressure exchange apparatus; a first PRO facility for performing a pressure-retarded osmosis by receiving the concentrated salt water discharged from the second pressure exchange apparatus as PRO salt water, and by receiving PRO salt water from the outside thereof; and a second PRO facility for performing a pressure-retarded osmosis by receiving the PRO salt water discharged from the first pressure exchange apparatus. According to the present invention, the seawater desalination system using a pressure-retarded osmosis technique can have higher energy efficiency.

Description

TECHNICAL FIELD [0001] The present invention relates to a seawater desalination system using pressure delayed osmosis technology,

The present invention relates to a seawater desalination system using pressure delay osmosis technology.

As demand for water for drinking or irrigation water continues to increase, the importance of seawater desalination technology is increasing. In addition, economically feasible and large-scale seawater desalination technologies are particularly important because of continued population growth and the growth of related industries.

Membrane-based desalination processes are still at a high level, although they consume less energy than thermal desalination processes, and the energy consumption rate needs to be lower than now for an environmentally and economically feasible desalination process.

Thus, several methods have been developed that include techniques for applying fluid energy generated in the forward osmosis and direct osmosis processes with low energy consumption desalination methods. Although the cleansing technology has a theoretically energyless mechanism, there is no actual application of it to the desalination process.

In order to apply continuous osmosis technology to a desalination process, a technique of extracting water from an induction solution and a recovery technique of an inducing solution are important for a continuous and practical process, but these techniques still have insufficient problems.

On the other hand, pressure-retarded osmosis (PRO) process technology is attracting attention as a technology capable of recovering or producing energy (Statkraft Osmotic Power Pilot Plant, Norway). However, in order to commercialize PRO process technology, it is required to develop innovative technology for maximum energy recovery or generation.

The driving force of the osmotic process is the difference in osmotic pressure between the two aqueous solutions facing the semi-permeable membrane. The osmotic pressure of the aqueous solution can be calculated by the Van't Hoff relation.

π = θ.v.c.R.T.

Where v is the number of ions generated during the desalination of the solute, θ is the osmotic coefficient, c is the concentration of all solutes (moles / l), R is the universal gas constant (0.083145 l.bar/moles.K) , And T is the absolute temperature (K).

The amount of water passing through the semi-permeable membrane due to the osmotic pressure difference is given by the following equation (McCutcheon and Elimelech, 2007).

Jw = A (? _{D, b} -? _{F, b} )

Here, _w is J and the water flow through a semi-transmissive film, A is a pure water permeability coefficient of the transflective film, π _{D, b} and π _{F, b} is the osmotic pressure of the bulk during each extraction and supply.

PRO is used to generate or recover energy (power) using the Gibbs free energy of mixing for the salinity difference of the two aqueous solutions (Sandler, SI, 1999, Chemical Engineering Thermodynamics, 3rd ed .; Wiley).

_{-ΔGmix = RT {[Σx i ln} (γ i x i)] M - θ A [Σx i ln (γ i x i)] A -θ B [Σx i ln (γ i x i)] B}

Where x _i is the mole fraction of species _i in solution, R is the gas constant, T is the temperature, and y is the activity coefficient of the reagent.

In the PRO system, a constant fluid pressure is applied to the high salt water solution, while the water permeates continuously from the low salt water solution, while the osmotic pressure difference between the two solutions is higher than the applied fluid pressure. The pressure of the high salt solution is preserved by the additional energy generated from the mixed Gibbs free energy while the volume flux of the solution is increased.

According to Yip and Elimelch (2012), the highest energy that can be extracted from a constant pressure PRO process is 0.75 kWh / m ³ when seawater and river are used as extraction and feed solutions, respectively. Therefore, in terms of pressure and volume, the extracted mixed Gibbs free energy may be used to generate energy for the process or to recover pressure.

For energy production schemes, an aquatic turbine may be used to produce power using the pressure and volumetric flux of the aqueous solution. Even though the efficiency of the latest Pelton turbines can reach 92%, the average efficiency is typically around 90%.

In the pressure recovery system, no mixed Gibbs free energy extracted from the PRO process has been applied to the pressure recovery in the desalination process. In recent reverse osmosis seawater desalination processes, pressure exchangers are applied to preliminarily pressurize seawater before returning to pressure by a brine and entering the RO process. This saves up to 60% of the energy required for preliminary pressurization of seawater for the RO process. Recent pressure exchangers, such as isobaric pressure exchangers, have efficiencies of up to 97%. Thus, in membrane-based seawater desalination technologies, pressure recovery can be a better alternative because it boasts higher efficiency than energy production.

An embodiment of the present invention is to provide a seawater desalination system using pressure-delayed osmosis technology with high energy efficiency by applying a PRO facility.

According to an aspect of the present invention, there is provided a water treatment system comprising: a first pressure exchange device for receiving seawater to increase pressure; A second pressure change device that receives at least a portion of seawater whose pressure is increased in the first pressure change device to increase the pressure; A SWRO facility for receiving seawater having a higher pressure in the first pressure exchanger and the second pressure exchanger to produce generated water filtered through a reverse osmosis membrane and delivering the concentrated brine to the second pressure exchanger; A first PRO facility in which the concentrated brine discharged from the second pressure exchange device is supplied as PRO brine, the PRO raw water is supplied from the outside, and the pressure delay osmosis process is performed; And PRO salt water which is discharged after the pressure reduction osmosis process in the first PRO facility and PRO raw water discharged after the pressure delay osmosis process in the first PRO facility, 2 PRO facility, the first pressure exchange device receives the PRO production water discharged from the second PRO facility, and transfers the pressure of the PRO production water to the seawater, and the second pressure exchange device receives the SWRO A seawater desalination system using a pressure delayed osmosis technology in which pressure of the PRO brine supplied from the facility is transferred to seawater and pressurized can be provided.

In addition, the first PRO facility and the second PRO facility may further include a PRO membrane module providing a transflective membrane for the pressure delay osmosis process, wherein the PRO membrane module comprises a PRO vessel in which at least one PRO vessel module is provided, System can be provided.

Also, a seawater desalination system using the pressure delayed osmosis technology in which the PRO brine discharged from the second half of the PRO vessel after being subjected to the pressure delay osmosis process of the first PRO facility is introduced into the second PRO facility can be provided.

Also, the PRO source water supplied from the outside is supplied to the second PRO facility, and the PRO brine discharged from the second half of the PRO vessel after passing through the pressure delay osmosis process of the first PRO facility is supplied to the second PRO facility A seawater desalination system using pressure delayed osmosis technology can be provided.

In addition, at least a part of the PRO brine introduced into the first PRO facility is transferred from the first half of the PRO vessel of the first PRO facility to the first pressure exchange device, and the pressure is transferred to the seawater. A desalination system may be provided.

Also, the PRO raw water supplied from the outside is supplied to the second PRO facility, and the PRO brine discharged from the second half of the PRO vessel after the pressure delay osmosis process of the first PRO facility is supplied to the first pressure exchange apparatus And at least a portion of the PRO brine introduced into the first PRO facility is introduced into the second PRO facility from the first half of the PRO vessel of the first PRO facility, A desalination system may be provided.

Also, a seawater desalination system using pressure delay osmosis technology in which the PRO source water supplied from the outside is supplied to the second PRO facility can be provided.

According to another aspect of the present invention, there is provided a pressure exchange apparatus comprising: a pressure exchange device for receiving a part of seawater supplied from outside to increase the pressure; A pressure regulator for increasing the pressure by supplying the rest of the seawater supplied from the outside; A SWRO facility for receiving seawater having a high pressure in the pressure exchanging device and the pressure regulating device to produce generated water filtered through a reverse osmosis membrane and delivering the concentrated brine to the pressure exchanging device; A first PRO facility in which the concentrated brine discharged from the pressure exchanger is supplied as PRO brine and the PRO source water is supplied from the outside to perform a pressure delayed osmosis process; The first PRO facility receives the PRO brine discharged through the pressure delayed osmosis process and receives the PRO raw water discharged from the first PRO facility through the pressure delayed osmosis process, PRO equipment; And an energy production device for generating available energy by receiving the PRO produced water discharged from the second PRO facility. The pressure exchange device transfers the pressure of the PRO brine supplied from the SWRO facility to seawater, A seawater desalination system using pressure delayed osmosis technology can be provided.

According to an embodiment of the present invention, by providing a method of applying an osmosis process such as PRO to a desalination process such as SWRO, the energy consumption of the SWRO process can be reduced by extracting mixed Gibbs free energy according to the pressure law have.

In addition, it is possible to maximize the recovery efficiency of the energy recovered in the desalination process by connecting the PRO facilities in multiple stages.

1 is a block diagram illustrating a seawater desalination system according to a first embodiment of the present invention.
2 is a block diagram illustrating a seawater desalination system in accordance with a second embodiment of the present invention.
3 is a conceptual diagram illustrating a connection structure between the first PRO module and the second PRO module of FIG.
4 is a conceptual diagram showing the first modification of Fig.
5 is a conceptual diagram showing a second modification of Fig.
Fig. 6 is a conceptual diagram showing the third modification of Fig. 3. Fig.
7 is a conceptual diagram showing the fourth modification of Fig.
8 is a conceptual diagram showing the fifth modification of Fig.
9 is a conceptual diagram showing the sixth modification of Fig.
10 is a block diagram illustrating a seawater desalination system according to a third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a block diagram illustrating a desalination system according to a first embodiment of the present invention.

Referring to FIG. 1, the seawater desalination system 1 according to the first embodiment of the present invention performs a process of receiving seawater containing salinity and converting it into fresh water through desalination. The supplied seawater is supplied to the DAF facility 110 and the UF facility 120 for pretreatment, and pre-treatment for desalination is performed. The DAF facility 110 is a facility for performing a treatment process for separating and removing algae or light gravity particles from the raw water. The UF facility 120 is a facility for performing an ultrafiltration membrane separation process, The raw water is filtered by a method of separating according to the size of the substance in the solution to remove the impurities first. Since the DAF process and the UF process correspond to well-known technical knowledge in the art, detailed process description will be omitted.

In this embodiment, the case where the DAF process and the UF process are carried out as the process of pretreatment of the seawater for desalination is described as an example, but the present invention can be freely modified within a range not impairing the spirit of the present invention, The DAF facility 110 and the UF facility 120 may be optionally replaced, modified and omitted.

The first brine 2, from which impurities such as algae have been removed, is introduced into the first pressure exchanger 130 through the pretreatment and is received under pressure to be pressurized. The second brine 3 in which the first brine 2 is pressurized via the first pressure changer 130 is separated into the third brine 4 and the fourth brine 5 by the multiway valve, The brine 5 flows into the second pressure exchanger 140. The fourth brine 5 pressurized by the second pressure exchanger 140 can be further pressurized by the second pressure regulator 160, for example, a booster pump.

Here, a pressure exchange device refers to a device that transfers pressure from a liquid flow on a higher pressure side to a liquid flow on a lower pressure side while preventing the flow of two liquids from mixing with each other. One example of such a pressure exchange device is disclosed in Laid-Open Publication No. 2014-0092836.

The third brine 4 is pressurized in the first pressure regulating device 150 such as a high pressure pump and then merged with the fourth brine 5 boosted by the second pressure regulating device 160 so that the reverse osmosis inflow 6 to the SWRO facility 170. The SWRO facility 170 is a facility for desalinating seawater by the reverse osmosis method. The SWRO facility 170 includes a reverse osmosis membrane capable of permeating water only through the reverse osmosis inflow 6 with a physical pressure equal to or higher than osmotic pressure.

The reverse osmosis inflow (6) desalinated through the SWRO facility (170) is discharged to the outside as low-salt, potable water (9), which is treated separately for other uses such as drinking, irrigation or industrial Can be utilized.

On the other hand, in the SWRO facility 170, the generated water 9 is filtered and concentrated and the concentrated brine 10 is introduced into the second pressure exchanger 140 to transfer the pressure to the fourth brine 5. The concentrated brine 10 may be pressurized to a predetermined pressure by the third pressure regulating device 180 such as a booster pump while the pressure is transferred from the second pressure changer 140 to the fourth brine 5. The concentrated brine 10 pressurized by the third pressure regulator 180 is introduced into the PRO facility 190 containing the PRO membrane for the osmosis process as a high salinity induction solution and used in the pressure delay osmosis process, (11).

In addition, PRO raw water 12 containing at least one of primary sewage treatment water, secondary sewage treatment water, tertiary sewage treatment water, brackish water, surface water and surface water is suitable for the pressure delayed osmosis process Water quality, water, pressure and volumetric flow rate and then supplied to the PRO facility 190.

The pretreated PRO raw water 12 is supplied as a feed solution to the PRO facility 190 and the induction solution and the feed solution introduced into the PRO facility 190 meet each other with the PRO membrane in the PRO facility 190 interposed therebetween, The salinity difference between the feed solutions causes water to flow out of the feed solution into the inductive solution, increasing the volume flow rate of the inductive solution. The specific configuration of the PRO facility 190 will be described later.

The extracted water exiting the PRO raw water 12 through the PRO membrane in the PRO facility 190 is very low in salinity and mixed Gibbs free energy is generated due to the salinity difference between the two solutions while being mixed with the PRO brine 11, The pressure of the PRO brine 11 is maintained by the mixed Gibbs free energy thus generated.

The PRO production water 13 discharged from the PRO facility 190 is increased in volume flow rate as compared to the PRO brine 11, while the pressure is relatively maintained. The PRO produced water 13 is discharged from the PRO facility 190 and then flows into the first pressure exchanger 130 and pressurizes the first brine 2 by transferring pressure to the first brine 2. After transferring the pressure to the first brine 2, the pressure of the PRO production water 13 is lowered and may be subjected to a separate treatment or process after being discharged from the first pressure exchange device 130.

On the other hand, the PRO raw water 12 loses its extracting water through the pressure delay osmosis process in the PRO facility 190, and the concentrated brackish water is transported to an external storage tank or the like as the PRO concentrated water 14 , Can be utilized through a separate post-processing or process.

According to the seawater desalination system of the present embodiment as described above, the PRO production water 13 discharged from the PRO facility 190 through the pressure delay osmosis process flows into the first pressure exchange device 130, The pressure is transferred to the first brine 2, where the energy conversion efficiency is 95% or more. Considering that the energy conversion efficiency is less than 80% when the pressure of the concentrated brine generated in the seawater desalination process is used for the production of electric energy by using an energy conversion facility such as a Peltton turbine, The effect can be greatly improved.

Meanwhile, in the case of the first embodiment described above, the PRO concentrated water 14 discharged from the PRO facility 190 is discharged to the outside of the system so that it is utilized separately. Thus, energy according to the pressure of the PRO concentrated water 14 To the outside of the system, resulting in deterioration of the energy efficiency of the entire system.

In order to solve the problems of the first embodiment, a second embodiment described later is proposed. The second embodiment to be described later differs from the first embodiment in that a PRO facility is composed of two stages, so that differences will be mainly described, and the same description and reference numerals will be used.

FIG. 2 is a block diagram showing a seawater desalination system according to a second embodiment of the present invention, and FIG. 3 is a conceptual diagram illustrating a connection structure between the first PRO module and the second PRO module of FIG.

2 and 3, the PRO facility 190 included in the seawater desalination system 1 'according to the second embodiment of the present invention includes a first PRO facility 192 and a second PRO facility 194 Stage configuration connected in series. The PRO brine 11 pressurized by the concentrated brine 10 in the third pressure regulator 180 is transferred to the first PRO facility 192 to perform the pressure delay osmosis process and the first PRO facility 192 Is supplied to the second PRO facility 194 to perform a pressure delayed osmosis process.

The PRO facility 190 includes a PRO vessel 196 in which a plurality of PRO vessels 196 are disposed in parallel and a PRO membrane module 198 disposed inside the PRO vessel 190 Is provided. The PRO vessel 196 may be configured to have a cylindrical structure having a hollow interior, for example, and a plurality of PRO vessels 196 arranged in parallel may be connected to each other through a common pipeline.

One or more PRO membrane modules 198 may be arranged in series in the respective PRO vessels 196. For example, the PRO membrane may be arranged to be spirally wound and maximized in surface area. The PRO membrane module 198 may be provided in each of the PRO vessels 196, or a plurality of the PRO membranes 198 may be provided. When a plurality of PRO membrane modules 198 are connected to the respective PRO vessels 196, the PRO membrane module 198 disposed closer to the inlet side of the PRO vessel 196 to which the inductive solution is supplied, A pressure delay osmosis process is performed in the order of the PRO membrane module 198 disposed close to the outlet side of the PRO vessel 196 to be discharged. In this specification, the inlet side of the PRO vessel 196 will be referred to as a front half portion 196a and the outlet side will be referred to as a rear half portion 196b.

(PRO salt water 11) is brought into contact with one side of the PRO membrane module 198 and the supply solution (PRO source water 12) is brought into contact with the other side of the PRO membrane module 198, At this time, the inductive solution is simultaneously supplied through the common piping connected to the inlet sides of all of the PRO vessels 196 provided in the PRO facility 190, and simultaneously discharged through the common piping connected to the outlet sides of all of the PRO vessels 196 . The supply solution is supplied through a raw water supply port formed at one side of each PRO vessel 196 and flows through each PRO vessel 196 while pressure delay osmosis proceeds, And is discharged through a raw water outlet formed on the other side.

In this embodiment, when a plurality of cylindrical PRO vessels 196 are arranged in parallel within the PRO facility 190 and one or more PRO membrane modules 198 are connected in series within the PRO vessel 196 However, the present invention is merely an example, and the specific configuration of the PRO facility 190 in which the pressure delay osmosis process is performed can be freely modified within a range that does not impair the spirit of the present invention.

In this embodiment, the PRO facilities 190 are provided in two stages. However, this is merely an example, and the PRO facilities 190 may be provided in three or more stages in series connection.

The PRO brine 11 is supplied as the inductive solution to the front half 196a of the PRO vessel 196 of the first PRO facility 192 and the PRO raw water 12 is supplied as the feed solution to the raw water supply port of the PRO vessel 196 So that a pressure delayed osmosis can be made while contacting the PRO membrane module 198. The pressure delayed osmosis can be progressively made while the inducing solution flows from the first half 196a to the second half 196b of the PRO vessel 196 so that the concentration of the inductive solution on the first half 196a is higher than that on the second half 196b Which is higher than the concentration of the inducing solution.

The inductive solution discharged to the outlet side of the PRO vessel 196 of the first PRO facility 192 through the pressure delayed osmosis process flows into the first half 196a of the PRO vessel 196 of the second PRO facility 194, The concentrated feed solution discharged from the first PRO facility 192 through the raw water outlet is again supplied to the raw water supply port of the PRO vessel 196 of the second PRO facility 194 and the pressure delayed osmosis process is performed again.

The supply solution injected into the second PRO facility 194 is transported and stored in an external storage tank or the like or the PRO concentrated water 14 discharged after the pressure delay osmosis process proceeds secondarily, Can be utilized. In addition, the PRO production water 13 discharged from the second PRO facility 194 is used to transfer the pressure to the first brine 2, as described above, into the first pressure exchange device 130.

In the seawater desalination system 1 'according to the present embodiment as described above, since the PRO process for energy generation is performed in two stages or more, the energy recovery is performed by making full use of the salinity difference between the inductive solution and the supply solution Therefore, there is an effect that the energy recovery efficiency can be maximized.

Meanwhile, the PRO facility 190 provided in multiple stages of the seawater desalination system 1 'according to the present embodiment can be modified in various ways in the connection method. Hereinafter, these modifications will be described with reference to the drawings.

4 is a conceptual diagram showing the first modification of Fig.

4, the PRO facility 190 according to the first modification is configured such that the PRO raw water 12 is supplied to the raw water supply port of the first PRO facility 192 and the raw water supply port of the second PRO facility 194 simultaneously And the concentrated feed solution discharged from the raw water outlet at the first PRO facility 192 is also supplied to the raw water supply port of the second PRO facility 194. According to the first modification, the salinity of the supply solution supplied to the second PRO facility 194 is lower than that of the second embodiment, so that the salinity difference at the second PRO facility 194 becomes larger, thereby enhancing the osmosis efficiency .

5 is a conceptual diagram showing a second modification of Fig.

5, the PRO facility 190 of the second modification is configured such that the PRO raw water 12 is supplied simultaneously to the raw water supply port of the first PRO facility 192 and the raw water supply port of the second PRO facility 194 And the concentrated feed solution discharged from the first PRO facility 192 through the raw water outlet is configured to be discharged to the outside together with the PRO concentrated water 14 without being supplied to the second PRO facility 194. [ According to the second modified example, the salinity of the PRO concentrated water 14 discharged as compared with the first modified example is lowered. However, since the salinity of the supply solution contacting with the induction solution through the two-step process becomes constant, And the efficiency can be stably operated.

Fig. 6 is a conceptual diagram showing the third modification of Fig. 3. Fig.

6, the PRO facility 190 of the third modification example is configured such that the PRO membrane module 198 disposed on the rear half 196b side of the first PRO facility 192 is connected to the PRO vessel 190 of the second PRO facility 194, A line through which the induction solution is delivered to the inlet side of the first PRO facility 192 is connected to the first pressure exchange device 130 via the PRO membrane module 198 disposed on the first half 196a side of the first PRO facility 192, The PRO line 13 is connected to the second PRO facility 194 and transferred to the first pressure exchange device 130 and the first PRO facility 192 is connected to the first PRO facility 192, And the induction solution discharged from the PRO membrane module 198 is combined and transferred to the first pressure exchange device 130. [ The inductive solution of the first PRO facility 192 delivered to the first pressure exchange device 130 and the PRO production number 13 of the second PRO facility 194 are used to transfer pressure to the first brine 2 . According to the third modification, it is possible to increase the flow rate of the salt water transferred from the first pressure exchanger 130 to the first brine 2, thereby increasing the salinity difference energy transmitted through the first pressure exchanger 130 have.

7 is a conceptual diagram showing the fourth modification of Fig.

Referring to FIG. 7, the PRO facility 190 of the fourth modified example is configured such that the supply solution discharged from the raw water outlet side of the first PRO facility 192 in the construction of the PRO facility 190 of the third modified example described above, PRO unit 194 is supplied as the supply solution of the second PRO facility 194 by merging with the PRO source water 12 to be supplied to the raw water supply port of the PRO facility 194. According to the fourth modified example, the supply solution discharged from the first PRO facility 192 is recycled once more as compared with the third modified example, thereby improving the utilization rate of the fresh water.

8 is a conceptual diagram showing the fifth modification of Fig.

8, the PRO facility 190 according to the fifth modification includes the PRO module 190 disposed on the first half of the first PRO facility 192 in the configuration of the PRO facility 190 according to the third modification described above, The PRO membrane module 198 configured to connect the lines to the first half 196a of the second PRO facility 194 and to introduce the inductive solution and to be placed on the second half 196b side of the first PRO facility 192 Is connected to the first pressure exchanger 130 so that the inductive solution in the PRO membrane module 198 disposed on the rear half 196b side of the 1 PRO facility 192 is connected to the first brine 2 As shown in FIG. According to the fifth modified example, the salinity of the inductive solution in the PRO membrane module 198 disposed on the side of the first half 196a is higher than that of the PRO membrane module 198 disposed on the second half 196b side It is possible to supply the second conductivity type solution 194 with the salinity-rich leading side portion 196a side to the second PRO facility 194, thereby improving the process efficiency of the second PRO facility 194 as compared with the third variant example There is an advantage to lose.

9 is a conceptual diagram showing the sixth modification of Fig.

Referring to Fig. 9, the PRO facility 190 of the sixth modification has a structure in which the supply solution discharged from the raw water outlet side of the first PRO facility 192 in the construction of the PRO facility 190 of the fifth modified example described above, PRO unit 194 is supplied as the supply solution of the second PRO facility 194 by merging with the PRO source water 12 to be supplied to the raw water supply port of the PRO facility 194. According to the sixth modified example, the supply solution discharged from the first PRO facility 192 is recycled one more than the fifth modified example, thereby improving the utilization rate of the fresh water.

On the other hand, the seawater desalination system 1 '' according to the third embodiment of the present invention will be described with reference to FIG. 10 is a block diagram illustrating a seawater desalination system according to a third embodiment of the present invention.

The present embodiment differs from the second embodiment in that it includes an energy generating device 132 instead of the first pressure changing device 130 as compared with the second embodiment. The description and the reference numerals will be used for the second embodiment. For reference, only one pressure exchange device is used in this embodiment, so what is described as a second pressure exchange device 140 in the second embodiment will be described as a pressure exchange device 140.

In the seawater desalination system 1 '' according to the present embodiment, the PRO production water 13 discharged from the second PRO facility is transferred to the energy generator 132 to produce available energy such as electric energy. Here, an example of the energy generator 132 is a Pelton turbine, but the spirit of the present invention is not limited thereto.

The first brine 2 supplied from the outside is directly branched into the third brine 4 and the fourth brine 5 to be introduced into the first pressure regulating device 150 and the second pressure changing device 140 .

According to the seawater desalination system 1 '' according to the present embodiment having the above-described configuration, it is possible to convert the energy contained in the PRO production water 13 discharged in the pressure delay osmosis process into available energy such as electric energy It is possible to produce the available energy with the desalination process. However, as described above, there is a disadvantage in that the energy efficiency can be somewhat lower than that of the second embodiment.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. For example, a person skilled in the art can change the material, size and the like of each constituent element depending on the application field or can combine or substitute the embodiments in a form not clearly disclosed in the embodiments of the present invention, Of the range. Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, and that such modified embodiments are included in the technical idea described in the claims of the present invention.

1, 1 ', 1'': Seawater desalination system 110: DAF facility
120: UF facility 130: first pressure exchange device
140: second pressure exchanger 150: first pressure regulator
160: second pressure regulator 170: SWRO facility
180: third pressure regulator 190: PRO equipment
192: first PRO facility 194: second PRO facility
196: PRO Bessel 198: PRO membrane module

Claims (8)

A first pressure exchange device for receiving seawater to increase the pressure;
A second pressure change device that receives at least a portion of seawater whose pressure is increased in the first pressure change device to increase the pressure;
A SWRO facility for receiving seawater having a higher pressure in the first pressure exchanger and the second pressure exchanger to produce generated water filtered through a reverse osmosis membrane and delivering the concentrated brine to the second pressure exchanger;
A first PRO facility in which the concentrated brine discharged from the second pressure exchange device is supplied as PRO brine, the PRO raw water is supplied from the outside, and the pressure delay osmosis process is performed; And
The first PRO facility receives the PRO brine discharged through the pressure delayed osmosis process and receives the PRO raw water discharged from the first PRO facility through the pressure delayed osmosis process, PRO equipment,
The first pressure exchange device receives the PRO produced water discharged from the second PRO facility, transfers the pressure of the PRO produced water to seawater,
And the second pressure exchange device transfers the pressure of the PRO brine supplied from the SWRO facility to the seawater to pressurize the seawater desalination system. The method according to claim 1,
The first PRO facility and the second PRO facility,
A seawater desalination system using pressure delayed osmosis technology wherein the PRO membrane module providing a transflective membrane for a pressure delayed osmosis process comprises a PRO vessel provided within at least one of the interior. 3. The method of claim 2,
And the PRO brine discharged from the second half of the PRO vessel after passing through the pressure delay osmosis process of the first PRO facility is input to the second PRO facility. 3. The method of claim 2,
The PRO source water supplied from the outside is supplied to the second PRO facility,
And the PRO brine discharged from the second half of the PRO vessel after passing through the pressure delay osmosis process of the first PRO facility is input to the second PRO facility. 5. The method of claim 4,
Wherein at least a portion of the PRO brine introduced into the first PRO facility is transferred from the first half of the PRO vessel of the first PRO facility to the first pressure exchange device to deliver pressure to the seawater, . 3. The method of claim 2,
The PRO source water supplied from the outside is supplied to the second PRO facility,
After passing through the pressure delay osmosis process of the first PRO facility, the PRO brine discharged from the second half of the PRO vessel is transferred to the first pressure exchange apparatus to transfer pressure to the seawater,
Wherein at least a portion of the PRO brine introduced into the first PRO facility is introduced into the second PRO facility from the first half of the PRO vessel of the first PRO facility. 6. The method according to any one of claims 3 and 5,
Wherein the PRO source supplied from the outside is supplied to the second PRO facility. A pressure exchange device for receiving a portion of seawater supplied from outside to increase the pressure;
A pressure regulator for increasing the pressure by supplying the rest of the seawater supplied from the outside;
A SWRO facility for receiving seawater having a high pressure in the pressure exchanging device and the pressure regulating device to produce generated water filtered through a reverse osmosis membrane and delivering the concentrated brine to the pressure exchanging device;
A first PRO facility in which the concentrated brine discharged from the pressure exchanger is supplied as PRO brine and the PRO source water is supplied from the outside to perform a pressure delayed osmosis process;
The first PRO facility receives the PRO brine discharged through the pressure delayed osmosis process and receives the PRO raw water discharged from the first PRO facility through the pressure delayed osmosis process, PRO equipment; And
And an energy production device for receiving the PRO produced water discharged from the second PRO facility to produce available energy,
Wherein the pressure swinging device transfers pressure of the PRO brine supplied from the SWRO facility to seawater to pressurize the seawater desalination system.

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