WO2011132427A1

WO2011132427A1 - Method for fluid membrane-separation power generation and system for fluid membrane-separation power generation

Info

Publication number: WO2011132427A1
Application number: PCT/JP2011/002335
Authority: WO
Inventors: 小西貴久; 小林顕太郎; 小泓誠
Original assignee: 日東電工株式会社
Priority date: 2010-04-21
Filing date: 2011-04-21
Publication date: 2011-10-27
Also published as: JP2013146642A

Abstract

Disclosed is a method for fluid membrane-separation power generation, said method being able to obtain a sufficient amount of pure fluid and to effectively take advantage of energy generated by a fluid treatment device containing a membrane separation device that is pressurized and cross-flow. The method for fluid membrane-separation power generation is characterized by separating a pressurized supplied fluid into a permeated fluid and a concentrated fluid using a cross-flow membrane separation device, and then, in a temperature difference power generation device that uses a high temperature fluid and a low temperature fluid, generating power using the aforementioned concentrated fluid as the high temperature fluid.

Description

Fluid membrane separation power generation method and fluid membrane separation power generation system

The present invention relates to a cross-flow type membrane separation apparatus using a separation membrane such as a microfiltration membrane (MF membrane), an ultrafiltration membrane (UF membrane), a nanofiltration membrane (NF membrane), and a reverse osmosis membrane (RO membrane). The present invention relates to a fluid membrane separation power generation method and a fluid membrane separation power generation system in which a supply fluid is separated into a permeation fluid and a concentrated fluid by using a temperature difference power generation device.

When performing fluid separation, membrane separation refers to the physical and chemical properties of the membrane such as the shape and size of the pores of the membrane, the physical and chemical properties such as the molecular shape and size of the substance to be treated, and the pressure. This is a separation method performed by a combination of three elements related to driving force such as a difference. For example, separation membranes intended for water treatment use microfiltration membranes (MF membranes), ultrafiltration membranes (UF membranes), nanofiltration membranes (NF membranes), reverse osmosis membranes (depending on the type and size of the substance to be separated. (RO membrane) and the like. These separation membranes are preferably used for ultrapure water production, brine or seawater desalination, wastewater treatment, and the like. Furthermore, it can be used for advanced processing such as separation, removal and recovery of harmful components from dyeing wastewater, electrodeposition paint wastewater, sewage, etc., and concentration of active ingredients in food applications.

For example, in the case of seawater desalination, that is, seawater desalination treatment, a composite reverse osmosis membrane provided with a polyamide-based separation functional layer is generally used. This composite reverse osmosis membrane constitutes a spiral type separation membrane element, and this separation membrane element is loaded in a pressure vessel to provide a cross flow type membrane separation device. Furthermore, in a seawater desalination apparatus including such a membrane separator, attempts have been made to recover pressure energy remaining in concentrated water by a recovery apparatus and use it for driving a pump (see Patent Document 1).

Regarding temperature difference power generation, a temperature difference power generation device that uses a temperature difference between hot seawater at high temperatures in the ocean surface and cold cold seawater at deep ocean depths is known. Such a temperature difference power generation device includes an evaporator, a condenser, a turbine directly connected to the generator, a pump, and the like, and these components are connected by pipes. In the case of a closed cycle system, a working fluid such as ammonia sealed in the apparatus is sent to an evaporator in a liquid state, and heated at a temperature of a high-temperature fluid such as warm seawater to become steam. After the steam rotates the turbine and the generator to generate electric power, the steam is cooled by a low-temperature fluid such as cold seawater in a condenser and becomes liquid again. A method of generating electricity by repeating this is a temperature difference power generation method (see Patent Document 2).

In addition, as a method of desalinating seawater using a temperature difference power generation device, in an open cycle system, a part of the high-temperature fluid flowing out from the evaporator is evaporated under negative pressure conditions to obtain water vapor, and the water vapor is condensed. There has been proposed a fresh water producing method for obtaining distilled water (see Patent Document 3).

JP 2000-167358 A Japanese Patent Application Laid-Open No. 07-091361 International Publication No. 2007/020707 Pamphlet

In the conventional membrane separation apparatus as described above, for example, a pressure higher than the osmotic pressure of seawater, that is, a pressure of about 5 to 7 MPa is required at the time of membrane separation by the reverse osmosis membrane method in seawater desalination. The energy required for water occupies most of the operating cost of the seawater desalination equipment, and is a factor that pushes up the water production cost. In response to this, efficiency has been studied by the method of recovering residual pressure energy as described above, but it is not sufficient because of its limitations in principle. Along with the increase, further efficiency and reduction of water production costs are required. In addition, although the seawater desalination has been studied in the temperature difference power generation device as described above, the so-called evaporation method is used, and it has been difficult to secure a sufficient amount of fresh water in the power generation device.

The present invention provides a fluid membrane separation power generation method and a fluid membrane separation power generation system capable of effectively utilizing energy generated in a fluid processing apparatus including a pressurized membrane separation apparatus and obtaining a sufficient amount of pure fluid. The purpose is to do.

According to the present invention, a pressurized supply fluid is separated into a permeation fluid and a concentrated fluid using a cross-flow type membrane separator, and then the concentrated fluid is used as a high temperature fluid in a temperature difference power generation device using a high temperature fluid and a low temperature fluid. The present invention provides a fluid membrane separation power generation method characterized by being used as a power generator.

The supply fluid before being supplied to the membrane separator is preferably used as the low-temperature fluid, and the concentrated fluid is preferably heated so that the temperature difference between the high-temperature fluid and the low-temperature fluid is 20 ° C. or more. Furthermore, it is preferable to use solar energy when heating the concentrated fluid.

The supply fluid is preferably seawater or water obtained by separating seawater, and the supply fluid is preferably pressurized at a pressure of 1 MPa to 10 MPa.

The present invention also includes a fluid processing apparatus including a pressurizing pump that pressurizes a supply fluid, and a cross-flow type membrane separator that separates the supply fluid pressurized by the pressurization pump into a permeating fluid and a concentrated fluid; A temperature difference power generation device that generates power using a temperature difference between a high temperature fluid and a low temperature fluid, wherein the concentrated fluid is directly supplied as a high temperature fluid from the fluid processing device. A fluid membrane separation power generation system is provided.

Preferably, the fluid processing device further includes a supply pump that supplies a supply fluid to the pressurizing pump, and a part of the supply fluid discharged from the supply pump is supplied to the temperature difference power generation system as a low temperature fluid. . In this case, the fluid processing apparatus further includes a storage tank that stores the supply fluid upstream of the supply pump, and the supply fluid used as the low-temperature fluid in the temperature difference power generation system may be returned to the storage tank. preferable.

Moreover, it is preferable that the fluid treatment device further includes a heating device for heating the concentrated fluid separated by the membrane separation device. In this case, the heating device is preferably a solar heating device that heats the concentrated fluid using solar energy.

In a fluid processing apparatus including a pressurization type membrane separator, heat energy is transferred from a pressurization pump to a supply fluid, so that the temperature of the supply fluid after pressurization becomes higher than the temperature of the supply fluid before pressurization. Then, by using the concentrated fluid separated from the supply fluid whose temperature has increased as a high-temperature fluid in the temperature difference power generation device, the thermal energy generated in the fluid processing device can be effectively utilized. In addition, if a membrane separator is used, a larger amount of pure fluid can be produced than the evaporation method, and a sufficient amount of pure fluid can be obtained. Furthermore, if the generated electric power is used as power for the pressure pump, the operating cost of the fluid processing apparatus can be reduced.

It is a block diagram which shows the structure of the fluid membrane separation power generation system which concerns on one Embodiment of this invention. It is a schematic block diagram which shows an example of a separation membrane element. It is a block diagram which shows the structure of the fluid membrane separation power generation system of a modification.

<Fluid membrane separation power generation method>
The fluid membrane separation power generation method of the present invention is a temperature difference power generation device that uses a high-temperature fluid and a low-temperature fluid after separating a pressurized supply fluid into a permeation fluid and a concentrated fluid using a cross-flow type membrane separation device. Electric power is generated using the concentrated fluid as a high temperature fluid. Here, the “cross-flow type membrane separation device” refers to a membrane separation device that discharges a permeated fluid and a concentrated fluid separately when supplied fluid is supplied.

The supply fluid used in the present invention is not limited as long as it can be separated into a permeated fluid and a concentrated fluid in a separation membrane included in a cross-flow type membrane separation device. It can be used for known methods such as desalination, wastewater treatment, dyeing wastewater, electrodeposition paint wastewater, sewage and other methods for separating harmful components, and concentration of active ingredients in food applications. It is preferably a fluid that continuously treats a certain amount such as domestic wastewater, agricultural water, and seawater. Among these, seawater for desalination of seawater, and water obtained by pretreating the seawater and the wastewater by sand filtration, precipitation and / or membrane separation can be preferably used.

The supply fluid is pressurized and supplied to the membrane separator. As this pressurizing method, a mechanical means such as a known pressurizing pump can be used, and the pressure applied at this time may be appropriately determined according to the performance of the supply fluid and the separation membrane, but generally 1 MPa. The pressure is preferably 10 MPa or less and more preferably 1.5 MPa to 8 MPa.

The membrane separation device generally has a configuration in which the separation membrane element is loaded in a pressure vessel that can withstand the pressurization of the supply fluid, or a configuration in which the separation membrane element is integrated with the pressure vessel. In the present invention, the separation membrane element is not particularly limited as long as it is a pressure-type and cross-flow type membrane separation device. For example, in a seawater desalination treatment, a spiral type separation membrane including a polyamide-based composite separation membrane is used. A membrane element is used.

There are an open cycle system, a closed cycle system, and a hybrid cycle system of these as the temperature difference power generation device, and an appropriate configuration among them can be used. These are commonly composed of an evaporator, a condenser, a turbine directly connected to a generator, a pump, and the like, and these components are connected by pipes. For example, in the case of a closed cycle system in which sea surface water is a high-temperature fluid and deep ocean water is a low-temperature fluid, a working fluid such as ammonia enclosed in this device is sent to the evaporator in a liquid state, and the inside of the evaporator Then, the steam is heated at the temperature of the surface water of the sea surface and becomes steam. After generating power by rotating the turbine and the generator, the steam is cooled by the condenser having the temperature of the deep sea water and becomes liquid again. Power can be generated by repeating this process. In the present invention, the concentrated fluid separated by the membrane separator is used as the high temperature fluid.

The concentrated fluid discharged from the membrane separation device and supplied to the temperature difference power generation device is appropriately heated as necessary and sent to the temperature difference power generation device as a high temperature fluid. Since such a concentrated fluid has a higher specific heat than seawater or tap water, the energy required for heating can be greatly reduced. The heating temperature of the concentrated fluid is appropriately determined according to the vaporization temperature of the working fluid and the sealing pressure, but is 15 ° C. or higher and 120 ° C. or lower. It is preferable that the temperature difference power generator operates with a high-temperature fluid of 15 ° C. or more and 50 ° C. or less. Further, the heating of the concentrated fluid is preferably performed so that the temperature difference between the high temperature fluid and the low temperature fluid is 20 ° C. or more.

The method of heating the concentrated fluid is not particularly limited, and heating power, heating wire, solar heat, etc. can be used as appropriate according to the surrounding environment and device design, but from the viewpoint of energy efficiency, sunlight, solar heat, etc. The method of heating using solar energy is preferable. As a heating method, a material having a high thermal conductivity such as a metal may be used as a supply fluid or concentrated fluid pipe, and appropriate known heating may be performed on the portion. In addition to using a transparent pipe as the pipe, a concave mirror is installed at a position symmetrical to sunlight and the fluid is heated, or one side of the transparent pipe facing the position symmetrical to sunlight is used as a mirror surface. It is also preferable to collect solar energy into a fluid and heat it. The heating position is preferably performed on the pressurized supply fluid in consideration of heat transfer from the pressurizing pump. Furthermore, it may be any of before, after and after membrane separation, and may be combined at a plurality of positions, but it is preferable to heat before and / or after membrane separation. Since it is known that when the fluid is heated before the membrane separation, the permeation performance of the separation membrane can be improved when a fluid having a temperature higher than room temperature is supplied to the separation membrane element, the permeation performance of the separation membrane can be improved. Further, since the membrane can be supplied to the membrane separation device at a constant temperature, the membrane separation performance can be easily controlled to be constant. Further, when heating is performed after membrane separation, only the concentrated fluid used as the high-temperature fluid can be efficiently heated without wasting heating energy. Therefore, it is preferable to preheat the pressurized supply fluid to about 40 ° C. or less before membrane separation and to heat to the required level after membrane separation.

The low-temperature fluid supplied to the temperature difference power generation device is not particularly limited except that it is a fluid that is not frozen and has no malfunction in flow, and preferably has a low temperature as much as possible. It is preferable to use a fluid of less than or equal to ° C. For example, a fluid other than the separation target fluid such as supply fluid to the separation membrane, river water, seawater, deep ocean water, or alcohol can be used. It is preferable to use a part of the supply fluid to the membrane, more preferably the supply fluid before pressurization.

The temperature difference between the low-temperature fluid and the high-temperature fluid is preferably 20 ° C. or higher, and preferably 25 ° C. or higher, when using a highly efficient apparatus such as a carina cycle or Uehara cycle using ammonia as the working fluid. The higher the temperature difference, the better. However, the temperature difference from the viewpoint of energy efficiency is 90 ° C. or less, preferably 50 ° C. or less.

When the supply fluid passes through the pump for pressurization, the temperature of the supply fluid rises by 2 to 3 ° C due to the transfer of thermal energy. This is because the difference in operating temperature required in the above wafer cycle is about 25 ° C., so this thermal energy is equivalent to about 10%, and this energy can be used without surplus.

Since the concentrated fluid separated by the membrane separator has a high pressure, it is preferable to recover pressure energy from the concentrated fluid using a pressure energy recovery device before being sent to the temperature difference power generation device. Examples of the pressure energy recovery device include PX series manufactured by Energy-Recovery. In the case of using the pressure energy recovery device, the pipes and devices up to the recovery device need to have a pressure resistant configuration capable of withstanding a high fluid pressure. For this reason, it is preferable that the pressure energy recovery device is provided immediately after the membrane separation device for supplying the pressurized supply fluid so that the pressure resistance configuration is minimized, and the subsequent fluid is appropriately decompressed. The pressure after depressurization at this time is not particularly limited, but is preferably about 0.1 to 2 MPa.

In addition, in the system of the temperature difference power generation device alone, a pump for flowing the high temperature fluid and the low temperature fluid is required respectively. However, according to the present invention, the fluid pressure of the membrane separation process can be used. It is possible to omit a flow pump other than the pump for flowing the working fluid in the apparatus. For example, the concentrated fluid is connected by a flow path so that the concentrated fluid flows continuously from the membrane separator of the fluid treatment device to the evaporator of the temperature difference power generator, and the pressure when the concentrated fluid is discharged from the membrane separator is used. If the concentrated fluid is supplied to the temperature difference power generation device, the pump for the high temperature fluid can be omitted. Further, when the supply fluid is used as the low temperature fluid, the pump for the low temperature fluid can be omitted. In either case, the energy saving effect is high.

The high-temperature fluid and the low-temperature fluid after being used for power generation by the temperature difference power generation device are not particularly limited, but it is preferable that the energy and fluid itself be returned to the fluid processing device and circulated. Regarding the high temperature fluid, in order to effectively use the high temperature, a method of desalination by various evaporation methods can be preferably used in combination. The low-temperature fluid is preferably returned as a supply fluid to the separation membrane element, but a method of supplying the pressure energy as a supply fluid to the pressure energy recovery device and supplying the pressure energy to the membrane separation device is preferably used. .

<Fluid membrane power generation system>
Although the specific example of the fluid membrane separation power generation system which performs the fluid membrane separation method of this invention is shown below based on FIG. 1, this invention is not limited to this.

FIG. 1 shows a fluid membrane separation system according to an embodiment of the present invention. In this fluid membrane separation system, a temperature difference power generation device 40 is provided on the downstream side of the fluid processing device 30. This will be explained step by step.

(Fluid treatment device)
The fluid processing apparatus 30 of this embodiment desalinates seawater. Specifically, the fluid processing apparatus 30 includes a cross-flow type membrane separation apparatus 10. On the line leading seawater to the membrane separation device 10, the water intake pump 1, the sand filtration device 2, the ultrafiltration membrane (UF membrane) pretreatment device 3, the UF filtration water tank (into the storage tank of the present invention) in order from the upstream side. 5), a supply pump 6, and a high-pressure pump 9 (corresponding to the pressurizing pump of the present invention) 9 are provided. The membrane separation device 10 separates the high-pressure supply water 102 supplied from the high-pressure pump 9 into permeated water 103 and concentrated water 104. A pressure energy recovery device 21, a solar heating device 11, and an electric boiler (second heating device) 12 are provided in this order from the upstream side on a line that guides the concentrated water 104 from the membrane separation device 10.

In this embodiment, a reverse osmosis membrane (RO membrane) separation device in which a spiral type separation membrane element including a polyamide composite separation membrane is loaded in a pressure vessel is used as the membrane separation device 10. As shown in FIG. 2, the spiral separation membrane element is formed around a central tube (water collecting tube) 51 in a state where a separation membrane 52, a supply-side flow passage material 54 and a permeation-side flow passage material 53 are laminated. It is wound in a spiral shape and fixed with an end member or an exterior material. At this time, each side of the separation membrane 52 is bonded as necessary, and the supply water 102 and the permeated water 103 are not mixed.

Examples of the polyamide composite separation membrane include a porous support provided with a separation functional layer made of a polyamide polymer.

The porous support is not particularly limited as long as it can form a separation functional layer, and a porous support made of polysulfone on a substrate such as a nonwoven fabric or a woven fabric is preferably used. In addition, a porous film such as polyimide, polyvinylidene fluoride, and epoxy can be used alone. At this time, the average pore diameter of the surface on which the separation functional layer of the porous support is provided is about 0.01 μm to 1 μm, and the thickness of the porous support is about 10 to 150 μm.

The polyamide-based separation functional layer can be formed using a known method. For example, an aqueous solution coating layer containing a polyfunctional amine component is formed on a porous support, and a polyfunctional acid halide component is formed there. The polyamide-based separation functional layer can be formed by contacting a solution containing. The contact time is usually 5 seconds to 5 minutes, and after the excess solution is removed, condensation polymerization is performed at the interface generated by the contact. Further, it is preferable to dry in air at 15 ° C. to 35 ° C. for about 1 to 10 minutes, and after the drying, the membrane surface is washed with deionized water.

Examples of the polyfunctional amine component include aromatic, aliphatic, or alicyclic polyfunctional amines. Moreover, these polyfunctional amine components may be used alone or as a mixture. As the polyfunctional acid halide component, aromatic, aliphatic, or alicyclic polyfunctional acid halides can be used. These polyfunctional acid halide components may be used alone or as a mixture.

Next, the operation of the fluid processing apparatus 30 will be described.

The fluid treatment device 30 first takes raw seawater (raw water) 101 from the intake pump 1 and stores it in the UF membrane filtration water tank 5 via the sand filtration device 2 and the ultrafiltration membrane (UF membrane) pretreatment device 3. At this time, for example, about 1 ppm of sodium hypochlorite is added from the drug injection device 4 for the purpose of suppressing the growth of microorganisms and sterilization. Thereafter, the water stored in the UF membrane filtration water tank 5 is supplied by the supply pump 6 at a pressure of, for example, about 0.5 MPa and supplied to the high-pressure pump 9. At that time, in order to suppress the chemical degradation of the RO membrane by sodium hypochlorite injected by the drug injection device 4, for example, 3 ppm of sodium bisulfite as a reducing agent is added from the drug injection device 7, and further hardly soluble salts. In order to suppress the generation of (scale), for example, 3 ppm of a scale inhibitor (Permatreat PC191 manufactured by Nalco) is injected from the drug injection device 8. The supply water, which was 20 ° C. at this time, is introduced to the membrane separation device 10 at a water temperature of 23 ° C. by being pressurized to, for example, about 5.5 MPa by the high-pressure pump 9, and concentrated with the permeated water 103. Separated into water 104.

The pressure energy is recovered from the concentrated water 104 by the pressure energy recovery device 21 immediately after. Specifically, in the pressure energy recovery device 21, the pressure energy is transferred to the supply water taken from the upstream side of the high-pressure pump 9, and the supply water that has become high pressure thereby is discharged from the high-pressure pump 9. Mix with. On the other hand, the concentrated water 104 depressurized by the pressure energy recovery device 21 is heated to, for example, 30 ° C. by the solar heating device 11 configured with black outdoor piping, and further heated to, for example, 50 ° C. by the electric boiler 12. The electric boiler 12 is provided to raise the temperature to 50 ° C. in conjunction with the heating state of the heating device 11, but depending on the temperature difference between the high temperature fluid and the low temperature fluid in the temperature difference power generation device 40, the electric boiler 12 is provided. One or both of the solar heating device 11 and the solar heating device 11 may not be provided. The heated concentrated water directly flows into the evaporator 13 described later as the high-temperature fluid 105 used in the temperature difference power generation device 40.

(Temperature difference power generator)
As the temperature difference power generation device 40, a concentrated fluid directly supplied from the fluid processing device 30 is used as the high temperature fluid 105, and a low temperature fluid 106 supplied separately is used to generate power based on these temperature differences. If it is, it will not be limited, but in this embodiment, the closed cycle system which repeats vaporization and liquefaction in the state which enclosed the working fluid 107 is employ | adopted.

Specifically, the temperature difference power generation device 40 has a working fluid circuit for circulating the working fluid. This working fluid circuit is configured by connecting an evaporator 13, a gas-liquid separator 15, a turbine 16 directly connected to the generator 17, a condenser 14, a storage tank 19, and a pump 20 in this order by pipes. . The working fluid 107 exchanges heat with the high temperature fluid 105 in the evaporator 13, and then is separated into working fluid vapor and working fluid liquid in the gas-liquid separator 15. The working fluid vapor is sent to the turbine 16 to generate electricity by rotating the generator 17. The electric power generated by the generator 17 is used as power for the high-pressure pump 9, for example. Thereafter, the working fluid vapor discharged from the turbine 16 is sent to the condenser 14, exchanges heat with the low temperature fluid 106, becomes a liquid, and enters the storage tank 19.

In the present embodiment, a part of the supply water discharged from the supply pump 6 in the fluid processing device 30 is supplied to the temperature difference power generation device 40 as the low temperature fluid 106, and the supply water used as the low temperature fluid 106 in the condenser 14 is supplied. It is returned to the UF filtration water tank 5 arranged on the upstream side of the supply pump 6. More specifically, as the low temperature fluid 106, water downstream from the supply pump 6 and upstream from the

drug injection devices

7 and 8 is used. On the other hand, the working fluid liquid separated by the gas-liquid separator 15 is temporarily stored in the storage tank 18, sent to the condenser 14, and then stored in the storage tank 19. The working fluid stored in the storage tank 19 is sent to the evaporator 13 by the pump 20. Power generation is performed by repeating this operation.

The evaporator 13 and the condenser 14 are not particularly limited as long as the high-temperature fluid, the low-temperature fluid, and the working fluid are not mixed, heat exchange can be appropriately performed, and further, no corrosion is caused by the fluid. Can be used. In the evaporator 13, it is preferable to reduce the pressure from the atmospheric pressure in order to facilitate vaporization. In addition, the size and shape of the evaporator 13 and the condenser 14 are preferably designed appropriately in consideration of heat exchange efficiency. As the turbine 16 and the generator 17, commercially available ones can be used as long as they are not corroded by the working fluid vapor.

Examples of the working fluid include ammonia, a chlorofluorocarbon compound, a hydrocarbon compound, water, and a mixture thereof. From the viewpoint of operation efficiency, a working fluid is a mixture of ammonia and water, and a substance using 70 to 95% by weight of ammonia. It can be particularly preferably used. For example, a mixture of 90% by weight of ammonia and 10% by weight of pure water may be used as the working fluid 107.

The pipe for connecting the constituent devices is not particularly limited, and a metal or resin pipe can be used, but a pipe having a particularly high heat insulating effect can be preferably used. If necessary, it is preferable to use an appropriate heat insulating material in order to increase efficiency.

(Modification)
The fluid membrane separation power generation system of the present invention is not limited to the one having the above-described configuration, and various modifications are possible. For example, as shown in FIG. 3, a tank 24 having a heat insulating structure that temporarily stores the concentrated water 104 may be provided between the fluid treatment device 30 and the temperature difference power generation device 40. Then, the concentrated water stored in the tank 24 may be circulated as the high-temperature fluid 105 by the circulation pump 23 via the evaporator 13 of the temperature difference power generator 40. In this case, a heating device that heats the concentrated water may be provided on the flow path that guides the concentrated water from the tank 24 to the evaporator 13.

Also, the same raw seawater 101 as the raw water processed by the fluid processing device 30 may be supplied from the intake pump 25 to the condenser 14 of the temperature difference supply device 40 as the low temperature fluid 106. In order to adjust the temperature in the tank 24, a configuration in which the low-temperature fluid that has flowed out of the condenser 14 is guided to the tank 24 by a flow path with the on-off valve 29 may be employed.

Furthermore, it is also possible to provide a concentration difference power generation device 50 on the route through which the concentrated water is discharged from the tank 24, and to generate power using the forward osmotic pressure energy of the concentrated water. In the concentration difference power generation device 50, the concentrated water discharged from the tank 24 and the raw seawater that has passed through the condenser 14 are guided to the membrane separation device 26 including a forward osmosis membrane. The concentrated water evaporates and rotates the turbine 27 directly connected to the generator 28 and then mixes with the raw seawater that has passed through the membrane separation device 26.

As described above, the present invention provides a fluid membrane separation power generation method and a fluid membrane separation power generation system using a fluid treatment device and a temperature difference power generation device. In this method and system, the pressure and thermal energy applied to the fluid of the fluid membrane separation that has been wasted until now can be consumed without wasting without affecting the performance of the fluid separation in the membrane separation. For example, the energy of 2 to 3 ° C. applied to the fluid by pressurization for membrane separation is about 10% with respect to the temperature difference of 20 to 30 ° C. which can drive the temperature difference power generation device with high efficiency. Since it is energy, at least the same level of energy saving can be realized. Further, by using the fluid flow pressure indispensable for fluid membrane separation, the power generation function can be operated without using a pump for flowing the high temperature fluid and the low temperature fluid, which is indispensable for driving the temperature difference power generation device.

DESCRIPTION OF SYMBOLS 1 Intake pump 2 Sand filtration device 3 Ultrafiltration membrane (UF membrane)

pretreatment device

4, 7, 8 Drug injection device 5 UF membrane filtration water tank (storage tank)
6 Supply pump 9 High-pressure pump (pressure pump)
DESCRIPTION OF SYMBOLS 10 Membrane separator 11 Solar heating device 12 Electric boiler (2nd heating device)
DESCRIPTION OF SYMBOLS 13 Evaporator 14 Condenser 15 Gas-liquid separator 16 Turbine 17

Generator

18, 19 Reservoir tank 20 Working fluid pump 21 Pressure energy recovery device 30 Fluid processing device 40 Temperature difference power generation device 50 Concentration difference power generation device 101 Raw water 102 RO membrane supply Water 103 Permeated water 104 Concentrated water 105 High temperature fluid 106 Low temperature fluid 107 Working fluid

Claims

After the pressurized supply fluid is separated into a permeation fluid and a concentrated fluid using a cross-flow type membrane separation device, power generation is performed using the concentrated fluid as a high temperature fluid in a temperature difference power generation device using a high temperature fluid and a low temperature fluid. A fluid membrane separation power generation method.
The fluid membrane separation power generation method according to claim 1, wherein a supply fluid before being supplied to the membrane separation device is used as a low temperature fluid.
The fluid membrane separation power generation method according to claim 1 or 2, wherein the concentrated fluid is heated so that a temperature difference between the high temperature fluid and the low temperature fluid becomes 20 ° C or more.
4. The fluid membrane separation power generation method according to claim 3, wherein the concentrated fluid is heated using solar energy.
The fluid membrane separation power generation method according to any one of claims 1 to 4, wherein the supply fluid is seawater or water obtained by separating seawater.
6. The fluid membrane separation power generation method according to claim 1, wherein the supply fluid is pressurized at a pressure of 1 MPa to 10 MPa.
The fluid membrane separation power generation method according to any one of claims 1 to 6, wherein the concentrated fluid is supplied to the temperature difference power generation device using a pressure when the concentrated fluid is discharged from the membrane separation device.
A fluid processing apparatus comprising: a pressurizing pump that pressurizes the supply fluid; and a cross-flow type membrane separation device that separates the supply fluid pressurized by the pressurization pump into a permeating fluid and a concentrated fluid;
A temperature difference power generation device that generates power using a temperature difference between a high temperature fluid and a low temperature fluid, wherein the concentrated fluid is directly supplied as a high temperature fluid from the fluid processing device; and
A fluid membrane separation power generation system.
The fluid processing apparatus further includes a supply pump that supplies a supply fluid to the pressurizing pump,
The fluid membrane separation power generation system according to claim 8, wherein a part of the supply fluid discharged from the supply pump is supplied to the temperature difference power generation device as a low temperature fluid.
The fluid processing apparatus further includes a storage tank that stores a supply fluid upstream of the supply pump, and the supply fluid used as a low-temperature fluid in the temperature difference power generation apparatus is returned to the storage tank. The fluid membrane separation power generation system described.
The fluid membrane separation power generation system according to any one of claims 8 to 10, wherein the fluid treatment device further includes a heating device that heats the concentrated fluid separated by the membrane separation device.
The fluid membrane separation power generation system according to claim 10, wherein the heating device is a solar heating device that heats the concentrated fluid using solar energy.
The fluid membrane separation power generation system according to any one of claims 8 to 12, wherein the electric power generated by the temperature difference power generation device is used as power for the pressure pump.