KR101594226B1 - Device for desalination of water - Google Patents

Abstract

The present invention relates to a desalination apparatus comprising a first filtration unit for transmitting seawater to a first reverse osmosis membrane to produce treated water, a second filtration unit for passing treated water discharged through the first reverse osmosis membrane through the second reverse osmosis membrane A seawater pump for supplying seawater to the first filtration unit, and a wastewater discharged from the second filtration unit without passing through the second reverse osmosis membrane, through the semipermeable membrane and passing through the semipermeable membrane And a seawater supply unit for supplying water to the first filtration unit. Thus, the electric energy required for driving the seawater pump can be reduced.

Description

{DEVICE FOR DESALINATION OF WATER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desalination apparatus, and more particularly, to a desalination apparatus capable of reducing electric energy required for driving a pump that transmits seawater to a reverse osmosis membrane to produce fresh water.

As is well known, the desalination apparatus is an apparatus for producing fresh water by removing ion components such as salt from brine.

In the desalination apparatus, an evaporation method and a reverse osmosis method are widely applied.

The reverse osmosis method is superior to the evaporation method in energy efficiency and is a desalination method widely used recently.

1 is a flow diagram showing a conventional desalination apparatus to which reverse osmosis is applied.

As shown in FIG. 1, the conventional desalination apparatus includes a filtration unit 20 having a reverse osmosis membrane 24 and transmitting seawater to the reverse osmosis membrane 24 to produce fresh water.

The filtration unit (20) has a tank (22) forming an internal space.

The inner space of the tank 22 is partitioned into a seawater space 26 and a fresh water space 28 by the reverse osmosis membrane 24.

Seawater flows into the seawater space 26.

Fresh water produced through the reverse osmosis membrane (24) is temporarily stored in the fresh water space (28) and then discharged.

The conventional desalination apparatus includes a pump 10 for supplying seawater to the seawater space 26 and for pressurizing seawater in the seawater space 26 to the reverse osmosis membrane 24.

With such a configuration, the conventional desalination apparatus is configured such that the pump 10 supplies seawater to the seawater space 26, and pressurizes the seawater in the seawater space 26 to the reverse osmosis membrane 24 by reverse osmosis do. Here, the reverse osmosis pressure refers to a pressure greater than the osmotic pressure acting on the seawater side of the seawater space 26 from the fresh water side of the fresh water space 28.

The seawater in the seawater space 26 pressurized by the reverse osmosis membrane 24 partially permeates the reverse osmosis membrane 24 leaving the ion component in the seawater space 26, do.

The wastewater discharged from the seawater space 26 to produce the fresh water is discharged to the sea S.

However, in such a conventional desalination apparatus, a considerable load is applied to supply the seawater to the filtration unit 20 by the pump 10, and a considerable amount of electric energy is consumed to drive the pump 10.

Further, the waste water discharged from the seawater space 26 is discharged into the sea S with a considerable pressure energy, resulting in waste of energy.

Accordingly, it is an object of the present invention to provide a desalination apparatus capable of reducing electric energy required for driving a pump for supplying seawater.

Another object of the present invention is to provide a desalination apparatus capable of recovering pressure energy from wastewater produced and discharged from fresh water.

In order to achieve the above-mentioned object, the present invention provides a filtration apparatus comprising: a first filtration unit having a first reverse osmosis membrane and permeating seawater to the first reverse osmosis membrane to produce treated water; A second filtration unit having a second reverse osmosis membrane and permeating the treated water discharged from the first filtration unit through the first reverse osmosis membrane to the second reverse osmosis membrane to produce fresh water; A seawater pump for supplying seawater to the first filtration unit; And a seawater supply unit having a semi-permeable membrane and configured to permeate wastewater discharged from the second filtration unit without passing through the second reverse osmosis membrane to the semipermeable membrane and supply the water having passed through the semipermeable membrane to the first filtration unit Thereby providing a desalination device.

The seawater supply unit may further include a chamber defining an inner space, and the inner space of the chamber may be partitioned into a first space and a second space by the semipermeable membrane.

The wastewater discharged from the second filtration unit is temporarily stored in the first space of the seawater supply unit and the seawater supplied to the first filtration unit is temporarily stored in the second space of the seawater supply unit.

The wastewater and the seawater passing through the seawater supply unit can be configured to have opposite flow directions.

The wastewater and the seawater passing through the seawater supply unit may be configured to have the same direction of flow.

The plurality of semipermeable membranes may be detachably attached to the seawater supply unit, and the plurality of semipermeable membranes may be arranged along the direction of the wastewater and the sea water flowing through the seawater supply unit.

The seawater supply unit may be configured such that the first space is disposed above the second space.

The wastewater discharged from the seawater supply unit may be configured to flow into the interior of the seawater pump.

The desalination apparatus may further include a pretreatment unit for removing foreign matter contained in seawater flowing into the seawater pump.

The desalination apparatus may further include a pressurizing unit for pressurizing the seawater flowing into the first filtration unit using the hydraulic pressure of the wastewater discharged from the first filtration unit.

The pressurizing unit includes: a turbine rotatably installed by wastewater discharged from the first filtration unit; And a compressor rotatably connected to the turbine to press seawater flowing into the first filtration unit.

The seawater pressurized by the compressor may be configured to be introduced into the seawater supply unit.

The desalination apparatus may further comprise a treated water pump for supplying treated water discharged from the first filtration unit to the second filtration unit.

The treatment water pump may be configured to adjust the internal pressure of the seawater supply unit by regulating the pressure applied to the treatment water supplied from the first filtration unit to the second filtration unit.

As described above, according to one embodiment of the present invention, the wastewater produced and discharged can be supplied to the filtration unit through the semipermeable membrane. Thus, the electric energy required for driving the pump for supplying seawater can be reduced.

In addition, pressure energy can be recovered from the wastewater produced and discharged from fresh water.

1 is a schematic view showing a conventional desalination apparatus,
FIG. 2 is a system diagram showing a desalination apparatus according to a first embodiment of the present invention;
FIG. 3 is a system diagram showing an embodiment of the seawater supply unit of FIG. 2;
FIG. 4 is a system diagram showing another embodiment of the seawater supply unit of FIG. 2;
FIG. 5 is a system diagram showing still another embodiment of the seawater supply unit of FIG. 2;
6 is a system diagram showing a desalination apparatus according to a second embodiment of the present invention.
7 is a schematic diagram showing an embodiment of the pressure energy recovery unit of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a system diagram showing a desalination apparatus according to a first embodiment of the present invention, and FIG. 3 is a systematic diagram showing an embodiment of a seawater supply unit of FIG.

2 and 3, the desalination apparatus according to the first embodiment of the present invention includes a first reverse osmosis membrane 154, and permeates seawater to the first reverse osmosis membrane 154 to produce treated water A first filtration unit (150); A second filtration unit 170 having a second reverse osmosis membrane 174 and permeating the treated water discharged from the first filtration unit 150 to the second reverse osmosis membrane 174 to produce fresh water; A seawater pump 120 for supplying seawater to the first filtration unit 150; And a semipermeable membrane 144. The wastewater discharged from the second filtration unit 170 is passed through the semipermeable membrane 144 and the water permeated through the semipermeable membrane 144 is supplied to the first filtration unit 150 And a water supply unit 140 for supplying water.

In addition, the desalination apparatus according to the first embodiment of the present invention may further include a pretreatment unit 110 for removing foreign matter contained in seawater flowing into the seawater pump 120.

The desalination apparatus according to the first embodiment of the present invention may further include a treated water pump 160 for supplying treated water discharged from the first filtration unit 150 to the second filtration unit 170 .

The first filtration unit 150 may include a first tank 152 forming an internal space.

The internal space of the first tank 152 may be partitioned into a first space 156 and a second space 158 by the first reverse osmosis membrane 154.

The first space 156 of the first filtration unit is connected to the first reverse osmosis membrane 154 of the seawater flowing into the inlet 156a through which the seawater flows and the inlet 156a through the first space of the first filtration unit. And a discharge port 156b through which the seawater that has not passed through is discharged to the wastewater.

The second space 158 of the first filtration unit may have a discharge port 158b through which the treated water having passed through the first reverse osmosis membrane 154 is discharged.

The second filtration unit 170 may include a second tank 172 forming an internal space.

The inner space of the second tank 172 may be partitioned into a first space 176 and a second space 178 by the second reverse osmosis membrane 174.

The first space 176 of the second filtration unit may have an inlet 176a through which the treated water discharged from the first filtration unit 150 through the first reverse osmosis membrane 154 flows.

In addition, the first space 176 of the second filtration unit may be configured such that the treated water that has not passed through the second reverse osmosis membrane 174 among the treated water flowing into the inlet 176a of the first space of the second filtration unit, And a discharge port 176b for discharging the gas.

The second space 178 of the second filtration unit may have a discharge port 178b through which the fresh water having passed through the second reverse osmosis membrane 174 is discharged.

The seawater supply unit 140 may include a chamber 142 forming an internal space.

The inner space of the chamber 142 may be partitioned into a first space 146 and a second space 148 by the semi-

The semipermeable membrane 144 may be detachably installed in the chamber 142 by a coupling means 143 provided along the inner wall of the chamber 142.

In the first space 146 of the seawater supply unit, wastewater discharged from the second filtration unit 170 may be temporarily accommodated.

The first space 146 of the seawater supply unit may include an inlet 146a through which the wastewater discharged from the second filtration unit 170 flows.

The first space 146 of the seawater supply unit includes a discharge port 146b through which the wastewater that has not passed through the semipermeable membrane 144 is discharged from the wastewater flowing into the inlet 146a of the first space of the seawater supply unit, .

In the second space 148 of the seawater supply unit, seawater supplied to the first filtration unit 150 may be temporarily accommodated.

The second space 148 of the seawater supply unit may include an inlet 148a through which seawater discharged from the seawater pump 120 flows.

In addition, the second space 148 of the seawater supply unit is configured such that the seawater introduced into the inlet port 148a of the second space of the seawater supply unit is discharged by the water having passed through the semi- And a discharge port 148b.

Here, the water that has passed through the semipermeable membrane 144 is water contained in the wastewater temporarily stored in the first space 146 of the seawater supply unit.

The inlet 146a and the outlet 146b of the first space of the seawater supply unit may be formed on opposite sides of the direction in which the waste water flowing through the first space 146 of the seawater supply unit flows.

The inlet 148a and the outlet 148b of the second space of the seawater supply unit may be formed on opposite sides of the direction in which the sea water flowing through the second space 148 of the seawater supply unit flows.

The inlet 146a of the first space of the seawater supply unit is formed on the side opposite to the inlet 148a of the second space of the seawater supply unit with respect to the chamber 142, The second space may be formed on the same side as the discharge port 148b.

The discharge port 146b of the first space of the seawater supply unit is formed on the same side as the inlet 148a of the second space of the seawater supply unit with respect to the chamber 142, The second space may be formed on the side opposite to the discharge port 148b.

Thus, the wastewater and the seawater passing through the seawater supply unit 140 may be in opposite flow directions.

Meanwhile, the first space 146 of the seawater supply unit may be disposed above the second space 148 of the seawater supply unit.

Here, the upper side means the opposite side of gravity based on the second space 148 of the seawater supply unit.

Therefore, the first space 146 of the seawater supply unit is positioned on the opposite side of the gravity direction with respect to the semipermeable membrane 144, and the second space 148 of the seawater supply unit is positioned with respect to the semipermeable membrane 144 And may be located on the gravitational direction side.

In addition, the desalination apparatus according to the first embodiment of the present invention may have a plurality of pipes 190, 191, 192, 193, 194, 195, 196, 197, 198, have.

Hereinafter, the operation and effect of the desalination apparatus according to the first embodiment of the present invention will be described.

First, seawater introduced into the pretreatment unit 110 in the sea S can be removed by a filter (not shown) provided in the pretreatment unit 110 or the like.

The seawater discharged from the pretreatment unit 110 may be mixed with wastewater discharged from the seawater supply unit 140 as described later.

The seawater mixed with the seawater discharged from the preprocessing unit 110 and the wastewater discharged from the seawater supply unit 140 is pressurized by the seawater pump 120 driven by electric energy, 2 space 148. In addition,

The seawater introduced into the second space 148 of the seawater supply unit may be supplied with water from the wastewater temporarily stored in the first space 146 of the seawater supply unit to increase the flow rate.

The seawater discharged in the second space 148 of the seawater supply unit may be introduced into the first space 156 of the first filtration unit.

The seawater introduced into the first space 156 of the first filtration unit can be pressurized to the first reverse osmosis membrane 154.

The seawater pressurized to the first reverse osmosis membrane (154) may be partially produced through the first reverse osmosis membrane (154) as treated water.

Here, the ion component contained in the seawater produced by the treated water can be mainly left in the first space 156 of the first filtration unit.

The treated water produced through the first reverse osmosis membrane 154 may be temporarily stored in the second space 158 of the first filtration unit and then discharged.

The treated water discharged in the second space 158 of the first filtration unit can be pressurized by the treated water pump 160 and enter the first space 176 of the second filtration unit.

The ion concentration of the seawater that does not pass through the first ROW filter 154 can be increased by the ion component of the seawater.

The seawater having an increased ion concentration may be discharged from the first space 156 of the first filtration unit as waste water of the first filtration unit 150.

The wastewater discharged from the first space 156 of the first filtration unit can be discharged to the sea S.

The treated water flowing into the first space 176 of the second filtration unit may be produced as fresh water through a part of the second reverse osmosis membrane 174.

Here, the ion component contained in the treated water produced in the fresh water may mainly remain in the first space 176 of the second filtration unit.

The fresh water produced through the second reverse osmosis membrane 174 is temporarily stored in the second space 178 of the second filtration unit and can be discharged.

Fresh water discharged in the second space 178 of the second filtration unit may be collected in the fresh water reservoir 180.

The treatment water that can not pass through the second reverse osmosis membrane 174 can have a high ion concentration due to the ion component of the treated water becoming fresh water.

The treated water having a high ion concentration can be discharged as wastewater from the second filtration unit 170 in the first space 176 of the second filtration unit.

The wastewater discharged in the first space 176 of the second filtration unit may be introduced into the first space 146 of the seawater supply unit.

The wastewater flowing into the first space 146 of the seawater supply unit can transmit the water component contained in the wastewater through the semipermeable membrane 144 by the osmosis phenomenon.

In general, the semipermeable membrane 144 is a membrane that selectively passes a substance according to the size of the molecules. The osmotic phenomenon is concentrated at the lower concentration of the solution (the lower osmotic pressure) at the boundary of the semipermeable membrane 144 It is a phenomenon that water moves to the higher side (the side with higher osmotic pressure).

At this time, the amount of water passing through the semipermeable membrane 144 is expressed by the following equation.

Jw = A (DELTA P-DELTA P)

Here, Jw is the amount of water passing through the semipermeable membrane 144.

Further, A is an osmotic coefficient of the semipermeable membrane 144.

Also, Δp is the value obtained by subtracting the osmotic pressure at the lower concentration from the osmotic pressure at the higher concentration.

In addition, ΔP is the value obtained by subtracting the lower concentration concentration from the higher concentration water pressure.

In this embodiment, the wastewater flowing into the first space 146 of the seawater supply unit is, for example, 5,000 ppm of Total Dissolved Solide (TDS), the osmotic pressure is 3 bar, the water pressure is 12 bar Lt; / RTI >

Further, the seawater flowing into the second space 148 of the seawater supply unit may be, for example, 40,000 ppm of total charged solids, osmotic pressure of 30 bar, and water pressure of 22 bar.

Accordingly,? P may be 27 bar (= 30 bar-3 bar),? P may be 10 bar (22 bar-12 bar), and? P-? P may be 17 bar (= 27 bar-10 bar).

Therefore, by the action force of 17 bar, water can be moved from the wastewater in the first space 146 of the seawater supply unit to the seawater in the second space 148 of the seawater supply unit.

By the movement of the water, the flow rate of the seawater in the second space 148 of the seawater supply unit can be increased, and consequently the flow rate of seawater flowing into the first space 156 of the first filtration unit is increased .

The wastewater discharged from the first space 146 of the seawater supply unit may be mixed with the seawater discharged from the pretreatment unit 110 and may be introduced into the seawater pump 120.

The desalination apparatus of the present embodiment includes the seawater supply unit 140 so that fresh water is produced in the second filtration unit 170 and introduced into the first filtration unit 150 from the discharged wastewater Water can be moved to sea water.

Thus, the load of the seawater pump 120 for supplying seawater to the first filtration unit 150 can be reduced, and the electric energy required for driving the seawater pump 120 can be reduced.

In addition, the second filtration unit 170 can recover the pressure energy due to the osmotic pressure from the wastewater produced and discharged.

Further, in the desalination apparatus of this embodiment, the first space 146 of the seawater supply unit may be disposed above the second space 148 of the seawater supply unit.

Thereby, the water pressure of the wastewater in the first space 146 of the seawater supply unit is lower than that of the first space 146 of the seawater supply unit, It can be increased by water level and gravity.

The increase in the hydraulic pressure of the wastewater in the first space 146 of the seawater supply unit can reduce the above-mentioned? P.

The decrease of DELTA P can smooth the movement of water passing through the semipermeable membrane 144. [

The desalination apparatus of this embodiment can control the pressure applied to the treated water supplied from the first filtration unit 150 to the second filtration unit 170 by the treated water pump 160.

Accordingly, the internal pressure of the seawater supply unit 140 communicated with the first filtration unit 150 can be adjusted.

More specifically, when the pressure to be applied to the treatment water supplied from the first filtration unit 150 to the second filtration unit 170 is increased by the treatment water pump 160, the second space of the seawater supply unit 148 can be reduced.

Accordingly, the DELTA P of the seawater supply unit 140 can be reduced.

On the other hand, when the pressure applied to the treatment water supplied from the first filtration unit 150 to the second filtration unit 170 is reduced by the treatment water pump 160, the second space 148 of the seawater supply unit is reduced, Can be increased.

Accordingly, the DELTA P of the seawater supply unit 140 can be increased.

That is, the ΔP of the seawater supply unit 140 can be adjusted by adjusting the load of the process water pump 160.

Here, in the formula relating to Jw (the amount of water passing through the semi-permeable membrane), although Jw is expressed as increasing as the ΔP is smaller, there is an optimum ΔP value which is not substantially expressed in the above equation .

The optimum? P value is a value determined by the ion concentration, temperature, etc. of the wastewater and seawater passing through the seawater supply unit 140.

Accordingly, in order to smoothly move the water in the seawater supply unit 140, it is necessary to keep the ΔP at the optimum ΔP value, and the treatment water pump 160 can perform such a role.

The desalination apparatus of this embodiment can lower the ion concentration of the seawater flowing into the first filtration unit 150 by introducing the wastewater discharged from the seawater supply unit 140 into the seawater pump 120 .

Generally, in order to produce fresh water from seawater, ion components contained in seawater must be removed to a certain level or less. In the reverse osmosis method, the higher the ion concentration of seawater is, The electric energy consumed increases.

Accordingly, the desalination apparatus of the present embodiment can reduce the electric energy required for driving the seawater pump 120 by lowering the ion concentration of the seawater flowing into the first filtration unit 150 as described above.

In this case, the △ п of the seawater supply unit 140 can be reduced by lowering the ion concentration of the seawater in the second space 148 of the seawater supply unit.

The decrease of DELTA p may reduce the Jw.

When the Jw decreases, the amount of seawater flowing into the first filtration unit 150 can be reduced.

When the amount of the seawater flowing into the first filtration unit 150 decreases, the load of the seawater pump 120 can be increased.

The increase in the load of the seawater pump 120 may increase the electric energy required to drive the seawater pump 120.

However, the treatment water pump 160 can reduce the DELTA P with an optimum DELTA P value corresponding to the DELTA P reduction.

Thus, it is possible to suppress an increase in electric energy required for driving the seawater pump 120 due to the decrease of DELTA P, by adjusting the DELTA P of the treated water pump 160. [

Meanwhile, in the desalination apparatus of the present embodiment, the wastewater and the seawater passing through the seawater supply unit 140 may flow in opposite directions.

As a result, the osmosis phenomenon can be uniformly generated in the entire permeation region of the semipermeable membrane 144.

In general, the permeability of the semipermeable membrane 144 decreases as the osmosis phenomenon continues, and the semipermeable membrane 144 having a lowered permeation efficiency is replaced with a new semipermeable membrane.

The desalination apparatus of this embodiment can be replaced with a new semipermeable membrane after uniformly using the entire permeable region of the semipermeable membrane 144.

More specifically, referring to FIG. 3, the following will be described.

First, in the case of this embodiment, the wastewater passing through the seawater supply unit 140 can be increased in ion concentration (osmotic pressure) as it flows from upstream (right side in the figure) to downstream (left side in the figure).

Further, the seawater passing through the seawater supply unit 140 may flow from the upstream (left side in the figure) to the downstream (right side in the figure), and the ion concentration (osmotic pressure) may be lowered.

That is, the ion concentration (osmotic pressure) of the wastewater becomes lower as it goes from the wastewater to the upstream side of the wastewater and from the upstream side of the wastewater (left side in the drawing) to the downstream side of the wastewater The ionic concentration (osmotic pressure) of the solution can also be lowered.

Accordingly, the concentration difference (osmotic pressure difference) of the wastewater and the seawater can be uniformly maintained in the entire permeation region of the semipermeable membrane 144.

In addition, osmosis phenomenon occurs uniformly in the entire permeation region of the semipermeable membrane 144, and the permeation efficiency can be lowered evenly.

The semipermeable membrane 144 having a uniform transmission efficiency lowered over the entire transmission region can be replaced if the transmission efficiency is lowered to a certain level.

Therefore, in the desalination apparatus of the present embodiment, since the permeation efficiency of the semipermeable membrane 144 is uniformly lowered in the entire permeation region, the wastewater and seawater flow in the same direction and the load is concentrated on the downstream side, Unlike the desalination apparatus to be replaced, waste is not generated.

Here, there may be another embodiment related to the replacement of the semipermeable membrane 144.

4 is a schematic diagram showing another embodiment of the seawater supply unit.

The seawater supply unit 240 shown in Fig. 4 can be configured such that the wastewater and seawater passing through the seawater supply unit 240 flow in the same direction.

The seawater supply unit 240 may include, for example, wastewater passing through the seawater supply unit 240 and a plurality of semipermeable membranes 244a, 244b, 244c, and 244d arranged along the sea water flow direction.

In this embodiment, the number of the semipermeable membranes 244 is four, but the number thereof can be appropriately adjusted.

The semipermeable membranes 244a, 244b, 244c, and 244d may be detached from the seawater supply unit 240.

In this case, the wastewater can flow from upstream (left side in the figure) to downstream (right side in the figure), and ion concentration (osmotic pressure) can be increased.

Further, the seawater may flow from the upstream (left side in the drawing) to the downstream (right side in the drawing), and the ion concentration (osmotic pressure) may be lowered.

That is, the concentration difference (osmotic pressure difference) between the wastewater and the seawater can be increased from the upstream side (left side in the drawing) to the downstream side (right side in the drawing) of the wastewater and the seawater.

Thus, the load is concentrated on the semipermeable membrane disposed on the downstream side (the right side in the drawing) of the wastewater and the seawater, and the permeation efficiency can be drastically reduced.

However, in this embodiment, the semipermeable membranes 244a, 244b, 244c, and 244d are provided in the small transmissive regions and only the semipermeable membranes having reduced transmission efficiency can be replaced by dividing the entire transmissive region into a plurality of small transmissive regions , Waste can be reduced as compared with the case where a semipermeable membrane having a size corresponding to the entire transmission region is provided.

5 is a schematic diagram showing another embodiment of the seawater supply unit.

As shown in FIG. 5, in the present embodiment, a plurality of the seawater supply units 240 may be provided, and the plurality of seawater supply units 24 may be provided in multiple stages in series and in parallel.

In this case, the concentration difference (osmotic pressure difference) between the wastewater and the seawater passing through the plurality of seawater supply units 240 decreases from the upstream side (left side in the figure) to the downstream side Can be large.

In the present embodiment, the plurality of seawater supply units 240 are arranged in a multi-stage in series and in parallel along the flow direction of the wastewater and the seawater, so that the load can be dispersed.

Further, the semipermeable membrane (not shown) provided on the downstream side (right side in the drawing) of the seawater supply unit 240 can be made of a material which is relatively expensive and has a high permeation efficiency.

On the other hand, a semipermeable membrane (not shown) provided on the upstream side (left side in the drawing) of the seawater supply unit 240 can be made of a material having a relatively low cost and a low permeation efficiency.

Thus, in this embodiment, the semipermeable membrane replacement cost can be reduced by dispersing the load and installing the semipermeable membrane having a relatively low load with a low-cost material.

FIG. 6 is a system diagram showing a desalination apparatus according to a second embodiment of the present invention, and FIG. 7 is a system diagram showing an embodiment of the pressure energy recovery unit of FIG.

Hereinafter, a desalination apparatus according to a second embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG.

The same reference numerals are given to the same and corresponding portions as those of the above-described embodiment and the drawings, and redundant explanations of some components may be omitted.

5 and 6, the desalination apparatus according to the second embodiment of the present invention includes a first reverse osmosis membrane 154, and permeates seawater to the first reverse osmosis membrane 154 to produce treated water A first filtration unit (150); A second filtration unit 170 having a second reverse osmosis membrane 174 and permeating the treated water discharged from the first filtration unit 150 to the second reverse osmosis membrane 174 to produce fresh water; A seawater pump 120 for supplying seawater to the first filtration unit 150; And a second filtration unit 170. The first filtration unit 150 is provided with a semipermeable membrane 144, and the wastewater discharged from the second filtration unit 170 is transmitted to the semipermeable membrane 144, and the water permeated through the semipermeable membrane 144 is supplied to the first filtration unit 150 A seawater supply unit 140; And a pressurizing unit 330 for pressurizing the seawater flowing into the first filtration unit 150 using the hydraulic pressure of the wastewater discharged from the first filtration unit 150.

The pressurizing unit 330 may include a turbine 332 rotatably installed by the wastewater discharged from the first filtration unit 150.

The pressurizing unit 330 is coupled to the rotating shaft 334 of the turbine 332 and is rotated by the rotation of the turbine 332 to pressurize the seawater flowing into the first filtration unit 150, A compressor 336 may be provided.

The desalination apparatus according to the second embodiment of the present invention further includes a plurality of pressurizing units 330 for communicating the pressurizing unit 330 with the first filtration unit 150, the seawater pump 120, Piping 392a, 392b, 397a, 397b.

Hereinafter, the operation and effect of the desalination apparatus according to the second embodiment of the present invention will be described.

The operation effect of the desalination apparatus according to the second embodiment of the present invention may be different from that of the first embodiment only by the operation effect of the pressurization unit 330. [

That is, the wastewater discharged from the first filtration unit 150 may flow into the turbine 332.

The wastewater flowing into the turbine 332 may rotate the turbine 332.

The turbine 332 is rotated and the discharged wastewater can be discharged to the sea S.

By the rotation of the turbine 332, the compressor 336 can be rotated.

Accordingly, the seawater discharged from the seawater pump 120 and introduced into the compressor 336 can be further pressurized by the rotation of the compressor 336.

The seawater pressurized and discharged from the compressor 336 may be introduced into the first space 156 of the first filtration unit through the second space 148 of the seawater supply unit.

The desalination apparatus of the present embodiment includes the pressurizing unit 330 so that the seawater flowing into the first filtration unit 150 can be discharged by using the water pressure of the wastewater discharged from the first filtration unit 150 It is possible to pressurize.

In addition, the desalination apparatus of the present embodiment includes the seawater supply unit 140, so that fresh water is produced in the second filtration unit 170 and flows into the first filtration unit 150 from the discharged wastewater Water can be moved to sea water.

Thus, the load of the seawater pump 120 for supplying seawater to the first filtration unit 150 can be reduced, and the electric energy required for driving the seawater pump 120 can be reduced.

In addition, the first filtration unit 150 can produce the treated water and recover the pressure energy due to the water pressure from the discharged wastewater.

In addition, the second filtration unit 170 can recover the pressure energy due to the osmotic pressure from the wastewater produced and discharged.

In order to avoid duplication, detailed description is omitted.

The foregoing has been shown and described with respect to specific embodiments of the invention. However, the present invention may be embodied in various forms without departing from the spirit or essential characteristics thereof, so that the above-described embodiments should not be limited by the details of the detailed description.

Further, even when the embodiments not listed in the detailed description have been described, it should be interpreted broadly within the scope of the technical idea defined in the appended claims. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

10: Pump 20: Filtration unit
22: tank 24: reverse osmosis membrane
26: Seawater space 28: Fresh water space
30: Fresh water reservoir 110: Pretreatment unit
120: Seawater pump 140: Seawater supply unit
142: chamber 143: engaging means
144: Semipermeable membrane 146: First space of the sea water supply unit
148: second space of the sea water supply unit 150: first filtration unit
152: first tank 154: first reverse osmosis membrane
156: first space 158 of the first filtration unit 158: second space of the first filtration unit
160: Process water pump 170: Second filtration unit
172: second tank 174: second reverse osmosis membrane
176: first space of the second filtration unit 178: second space of the second filtration unit
180: Freshwater reservoir 240: Seawater supply unit
242: chamber 243: engaging means
244a, 244b, 244c, 244d: Semipermeable membrane 246: First space of the sea water supply unit
248: second space of seawater supply unit 330:
332: turbo 334: rotating shaft
336: Compressor S: Sea

Claims (14)

A first filtration unit having a first reverse osmosis membrane and transmitting seawater to the first reverse osmosis membrane to produce treated water;
A second filtration unit having a second reverse osmosis membrane and permeating the treated water discharged from the first filtration unit through the first reverse osmosis membrane to the second reverse osmosis membrane to produce fresh water;
A seawater pump for supplying seawater to the first filtration unit; And
And a seawater supply unit provided with a semipermeable membrane and transmitting wastewater discharged from the second filtration unit without passing through the second reverse osmosis membrane to the semipermeable membrane and supplying water permeated through the semipermeable membrane to the first filtration unit In addition,
Wherein the seawater supply unit includes a chamber defining an inner space, wherein an inner space of the chamber is partitioned into a first space and a second space by the semipermeable membrane, and the second space of the seawater supply unit is divided into a first space and a second space, And the seawater supplied to the first filtration unit is temporarily housed in the second space of the seawater supply unit and the first space is disposed on the upper side of the second space,
A turbine rotatably installed by hydraulic pressure of wastewater discharged from the first filtration unit; And a compressor rotatably connected to the turbine to press seawater flowing into the first filtration unit. delete delete The method according to claim 1,
Wherein the wastewater and the seawater passing through the seawater supply unit are opposite in flow direction. The method according to claim 1,
Wherein the wastewater and the seawater passing through the seawater supply unit have the same flow directions. 6. The method of claim 5,
A plurality of semipermeable membranes are provided,
Wherein each of the semipermeable membranes is detachably attached to the seawater supply unit,
Wherein the plurality of semipermeable membranes are arranged along the direction of the wastewater and the sea water flowing through the seawater supply unit. delete The method according to claim 1,
Wherein the wastewater discharged from the first space of the seawater supply unit flows into the interior of the seawater pump. The method according to claim 1,
And a pretreatment unit for removing foreign matter contained in seawater flowing into the seawater pump. delete delete The method according to claim 1,
Wherein the seawater pressurized by the compressor is introduced into the seawater supply unit. The method according to claim 1,
And a treatment water pump for supplying treatment water discharged from the first filtration unit to the second filtration unit. 14. The method of claim 13,
Wherein the treatment water pump adjusts the internal pressure of the seawater supply unit by regulating the pressure applied to the treatment water supplied from the first filtration unit to the second filtration unit.

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