Technical field
[0001]
This invention relates to water treatment systems and water treatment method for processing desalination, for example seawater.
BACKGROUND
[0002]
For example, as disclosed in Patent Document 1, the water treatment system seawater processing desalination comprises a desalination treatment apparatus using a reverse osmosis membrane or the like.
　Such water treatment systems, in order to suppress the performance degradation due to contamination of a reverse osmosis membrane desalination apparatus, upstream of the desalination apparatus, the particulate matter in seawater, a filtration device for filtering bacteria like there is a case that is equipped.
CITATION
Patent Document
[0003]
Patent Document 1: JP 2011-120988 JP
Summary of the Invention
Problems that the Invention is to Solve
[0004]
　Incidentally, for example the Middle East, etc., when using the water treatment system temperature is at a high area, the temperature is high seawater to be introduced as treatment water in the water treatment system. Furthermore, the waste water is used with a temperature rise as the coolant in power plants and the like may be treated with the water treatment system, the temperature of the water to be treated is high.
[0005]
　In the water treatment system, the temperature of the water to be treated is high, or reduced salt rejection in a reverse osmosis membrane, damage organic matter and a resin such as polyamide forming the reverse osmosis membrane, the durability is lowered Sometimes.
　This invention, even when the temperature of the water to be treated is high, and an object thereof is to provide a water treatment system and a water treatment method can exhibit high performance.
Means for Solving the Problems
[0006]
　According to a first aspect of the invention, the water treatment system, a waste water introduction portion for introducing the waste water above the predetermined temperature of the water to be treated, separating the treated water from the drainage inlet portion and concentrated water and fresh water includes a reverse osmosis membrane apparatus that, and a cooling unit for cooling the water to be treated supplied to the reverse osmosis unit.
[0007]
　Thus, when introducing more than a predetermined temperature of the effluent as treated water, cooling the water to be treated, it is possible to suppress the damage to the reverse osmosis membrane of the reverse osmosis unit. Thus, decrease in salt rejection of the reverse osmosis membrane, it is possible to suppress the deterioration of the durability.
[0008]
　According to a second aspect of the invention, the water treatment system, in a first aspect, the provided upstream of the reverse osmosis unit, the filtering process by the filter material layer biofilm formed water to be treated it may further comprise a filtration device for performing.
　With such a configuration, by cooling the predetermined temperature or higher of the water to be treated can be suppressed to decrease the growth rate of the organism to form the biofilm. Thus, it is possible to suppress deterioration in filtration performance of the filtration device.
[0009]
　According to a third aspect of the invention, the water treatment system, in any one of the aspects of the first or second aspect, wherein the cooling unit, the object treated by heat exchange between the refrigerant the water to be treated water may be provided with a treated water cooling unit for cooling.
　Thus, the water to be treated and the refrigerant in the water to be treated a cooling unit by heat exchange, it is possible to reliably cool the treated water.
[0010]
　According to a fourth aspect of the invention, the water treatment system, in a third aspect, the temperature detecting section for detecting the temperature of the water to be treated, based on the temperature of the water to be treated detected by the temperature detecting unit the may be provided and a control device for increasing control the supply amount of the refrigerant in the water to be treated a cooling unit when the temperature of the water to be treated is equal to or larger than the threshold.
　With this configuration, it is possible in accordance with the temperature of the water to be treated, automatically adjusts the degree of cooling of the water to be treated in the cooling unit. This makes it possible to reliably cool the treated water to a proper temperature.
[0011]
　According to a fifth aspect of the invention, the water treatment system in the third or fourth aspect, wherein a temperature detector for detecting the temperature of the water to be treated, a bypass path provided to bypass the cooling unit When a flow regulating valve for regulating the flow rate of the treated water can flow to the bypass passage, based on the temperature of the water to be treated detected by the temperature detecting unit, temperature is above a threshold value of the water to be treated If, by controlling the flow rate adjusting valve, and a control device for reducing the flow rate of the treated water to be circulated in the bypass passage, it may be provided with a.
　With this configuration, by circulating the water to be treated bypass passage bypassing the cooling unit, through the cooling unit by reducing the flow rate of the water to be treated, it is possible to suppress the amount of cooling water to be treated . Further, when the temperature of the water to be treated is not less than the threshold value, if reducing the flow rate of the for-treatment water to be circulated in the bypass passage, the flow rate of the water to be treated is increased through the cooling unit, the cooling amount of the water to be treated it can be increased. In this way, the temperature of the cooling water, and adjust the flow rate of the water to be treated at a cooling unit, it is possible to adjust the water to be treated appropriate temperature.
[0012]
　According to a sixth aspect of the invention, the water treatment system, in any one of aspects from the first fifth aspect, wherein the cooling unit, the seawater supply channel for mixing seawater taken from the ocean into the water to be treated it may be provided with.
　With this configuration, when towards the sea than water to be treated is low, by mixing the seawater to the water to be treated, it is possible to reduce the temperature of the water to be treated.
[0013]
　According to a seventh aspect of the invention, the water treatment system, in any one of aspects from the first sixth aspect, a heating unit for heating the water to be treated, it may be further provided.
　With this configuration, when the temperature of the water to be treated is too low, it is also possible to heat the water to be treated in the heating unit.
[0014]
　According to an eighth aspect of the invention, the water treatment system, in any one of embodiments from second seventh aspect, wherein the cooling unit, the reverse osmosis membrane concentrated water discharged from the reverse osmosis unit a return path for returning upstream of the apparatus, and the concentrated water cooling unit for cooling the concentrated water by causing the said concentrated water and the refrigerant flowing through the return passage to heat exchange, may be provided with a.
　In such a configuration, is discharged from the reverse osmosis unit, refluxed for concentrated water cooled in concentrated water cooling section upstream of the reverse osmosis unit, by mixing with water to be treated, the temperature of the water to be treated it can be lowered.
[0015]
　According to a ninth aspect of the invention, the water treatment system in the eighth embodiment, the return path, the concentrated water that has been cooled by the concentrated water cooling unit, and said filtration device and said reverse osmosis membrane apparatus and while may be circulated to at least one of the upstream side of the filtration device.
　With this configuration, if to reflux the cooled concentrated water between the filtering apparatus and the reverse osmosis unit, it is possible to reduce the temperature of the water to be treated which passed through the reverse osmosis unit. Further, if the reflux the cooled concentrated water to the upstream side of the filter, it is possible to reduce the temperature of the water to be treated that passed through the filtration device and a reverse osmosis unit.
[0016]
　According to a tenth aspect of the invention, the water treatment system in the eighth or ninth aspect, wherein the cooling in concentrated water cooling unit, the reflux water adjusting unit for adjusting the flow rate of the concentrated water to reflux in the reflux passage When the temperature detecting unit for detecting the temperature of the water to be treated, said a concentrated water temperature detector for detecting the temperature of the concentrated water, the temperature of the water to be treated detected by the temperature detecting unit and the concentrated water temperature based on the temperature of the concentrated water that has been detected by the detection unit, and a reflux water control unit for controlling the flow rate of the concentrated water to reflux in the reflux path in the return water amount adjusting unit may further comprise a.
　With this configuration, the temperature of the water to be treated, depending on the temperature of the concentrated water, and refluxed at the reflux passage by adjusting the amount of concentrated water to be mixed to the water to be treated, the temperature of the water to be treated it can be adjusted.
[0017]
　According to an eleventh aspect of the invention, the water treatment system, in any one of aspects from the first tenth aspect, wherein the cooling unit is to the treatment water so as to cool the 25 ~ 40 ° C. it may be.
　With this configuration, it is possible to reliably suppress damage to the reverse osmosis membrane. Further, when equipped with a filtration device, the growth rate of the organism to form biofilms can be reliably suppressed from being lowered.
[0018]
　According twelve aspect of the invention, the water treatment method includes the steps of introducing a predetermined temperature or more of the water to be treated, a step of cooling the water to be treated is introduced, the cooled the water to be treated, and a step of separating into a concentrated water and fresh water.
　With this configuration, by cooling the predetermined temperature or higher of the water to be treated, the treatment water, reduction of the salt rejection of the reverse osmosis membrane is separated into a concentrated water and fresh water, the deterioration of the durability it can be suppressed.
Effect of the invention
[0019]
　According to the above-described water treatment system and a water treatment method, even when the temperature of the water to be treated is high, it can exhibit high performance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020]
FIG. 1 is a diagram showing the overall configuration of a water treatment system of the first embodiment of the present invention.
Is a diagram showing the flow of FIG. 2 water treatment method in the water treatment system of the first embodiment.
3 is a diagram showing a configuration of a first modification of the water treatment system of the first embodiment.
4 is a diagram showing a configuration of a second modification of the water treatment system of the first embodiment.
5 is a diagram showing a configuration of a third modification of the water treatment system of the first embodiment.
6 is a schematic diagram showing the construction of a water treatment system in the second embodiment.
7 is a schematic diagram showing the construction of a water treatment system in the third embodiment.
8 is a diagram showing the configuration of a water treatment system according to a first modification of the third embodiment.
9 is a diagram showing the configuration of a water treatment system in the second modification of the third embodiment.
DESCRIPTION OF THE INVENTION
[0021]
　It will be described below with reference to water treatment systems and water treatment method according to an embodiment of the invention with reference to the drawings.
(First Embodiment)
　FIG. 1 is a diagram showing the overall configuration of the water treatment system of this embodiment.
　As shown in FIG. 1, the water treatment system 10 of this embodiment includes a raw water tank 11, a preprocessing unit 20, a cartridge filter 30, a high pressure pump 40, a desalination unit 50, an energy recovery device 60 , cooling unit includes a (the cooling water cooling unit) 100A, a.
[0022]
　The water treatment system 10 uses the waste water was used as cooling water in various plants such as power stations treatment water W1. The waste water is a seawater taken at intake pump (not shown), the result used as cooling water in the plant, than seawater temperatures in the sea, for example, a 5 ~ 10 ° C. of about high temperatures. In this embodiment, the drainage of the water to be treated W1 is, for example, a high temperature above 35 ° C.. For example, the temperature of the water treatment system 10 East, etc., even if the sea water temperature installation in area, the treatment water W1 which has water intake from the sea, for example, it may become a high temperature state above 35 ° C..
[0023]
　The raw water tank 11, intake pipe by a pump 12 (drainage inlet portion) of the treatment water W1 sent into the plant-side through P1, temporarily stored.
[0024]
　Preprocessing section 20 is provided on the downstream side of the raw water tank 11. Preprocessing section 20, the treatment water W1 which has been stored in the raw water tank 11 is fed through the connecting pipe P2. Preprocessing section 20 is provided with a filtration device 21A, 21B, and 21C. In this embodiment, two of the filter 21A upstream, 21B are provided in parallel, these filtering devices 21A, filtration apparatus 21C of one on the downstream side with respect to 21B are provided in series. These filtering devices 21A, 21B, 21C is the treatment water W1 which has been fed, the water flow prior to desalination unit 50, before the desalting is performed by the desalination process unit 50 in other words, to a filtration treatment , to remove suspended substances in the water to be treated W1. In this embodiment, as a pre-processing unit 20, a filtration device 21A is sand filtration apparatus, 21B, and 21C using, without turned such as flocculants and pH adjusting agent, performs so-called Mukusuri Note pretreatment.
　Filtration device 21A, 21B, 21C are respectively equipped with one or more stages of the filter unit 21f. Filter unit 21f is a filter medium, and a predetermined amount of sand (not shown), biofilm grown and maintained on the surface of the sand and (not shown), a. Filter unit 21f is a biofilm, soil the desalination process unit 50, for example, components that cause fouling of the reverse osmosis membrane, specifically, suspended solid, inorganic particles, organic particles, a polymer organic material, and, to remove such microorganisms. Filter unit 21f is the sand to remove fines component contained in the treatment water W1.
[0025]
　Cartridge filter 30, on the downstream side of the pretreatment unit 20 are connected via the connecting pipe P3. Cartridge filter 30, were not removed by the pre-processing unit 20, for example, 1 ~ 5 [mu] m about fine foreign matter so as not to enter the high-pressure pump 40, removing foreign matter on a given diameter or.
[0026]
　High-pressure pump 40, the downstream side of the cartridge filter 30, are connected via a connecting pipe P4. High-pressure pump 40, the treatment water W1 which has passed through the cartridge filter 30, and raised to a predetermined pressure is fed into the desalination unit 50 through the connection pipe P5.
[0027]
　Desalination unit 50 performs desalted. Here, the desalting treatment, for example, remove salts in seawater, or a process of concentrating. Desalination unit 50 in this embodiment, for example, using a reverse osmosis membrane F, to remove ion components from the for-treatment water W1. In this embodiment, as desalination unit 50, and a reverse osmosis unit 51, 52 of the two-stage in series.
[0028]
　First-stage reverse osmosis membrane device 51, the downstream side of the high-pressure pump 40 are connected via a connecting pipe P5. Reverse osmosis unit 51, the treatment water W1 which has been boosted by the high-pressure pump 40, via the connecting pipe P5 is passed through the reverse osmosis membrane F, obtain permeated water salinity (ionic components) have been removed. The resulting permeate is fed to the reverse osmosis unit 52 of the second stage via a connecting pipe P6. Concentrated water W2 containing ion components removed in the reverse osmosis membrane device 51 is sent to the energy recovery device 60 via the connection pipe P7. Concentrated water W2 passing through the energy recovery device 60 is stored in the drain tank 13 through the connection pipe P8, and is discharged to the outside (sea) at an appropriate timing.
[0029]
　Reverse osmosis unit 52 in the second stage, downstream of the reverse osmosis unit 51, it is connected via a connecting pipe P6. Reverse osmosis membrane device 52, by passing the permeate through the reverse osmosis unit 51 to the reverse osmosis membrane F, to further remove the ion components, to obtain pure water. The resulting pure water, via the connecting pipe P9, are stored in the water tank 14. Here, in the case where pure water obtained a beverage or the like, adding minerals to the water tank 14. Concentrated water W3 comprising ionic components removed in the reverse osmosis membrane device 52 is stored in the drain tank 13 through the connection pipe P10, and is discharged to the outside (sea) at an appropriate timing.
[0030]
　Energy recovery device 60 recovers the energy from the concentrated water W2 discharged from the reverse osmosis unit 51. Concentrated water W2 discharged from the reverse osmosis unit 51 is pressurized by the high pressure pump 40. Energy recovery device 60 is provided with a rotor (hydraulic turbine) 61 that is rotated by water flow concentrated water fed from the connection pipe P7. The rotor 61, with the rotational energy by pressurized concentrated water rotates the rotor 62 which is integrally connected to the rotor 61. Downstream of the cartridge filter 30, the branch pipe P12 is provided to branch from the connecting pipe P4. Some of the treated water W1 which has passed through the cartridge filter 30 is fed to the reverse osmosis unit 51 by the rotor 62 through the energy recovery device 60 through the branch pipe P12. Thus, as part of the energy feeding the treatment water W1 in the reverse osmosis unit 51, it is possible to use the energy of concentrated water recovered by the energy recovery device 60.
[0031]
　Cooling section 100A cools the treated water W1 is supplied to the reverse osmosis unit 51. Cooling section 100A, for example, it provided in the middle of the intake pipe P1. As the cooling section 100A, for example, it may be used a cooling tower. The cooling tower to cool the treated water W1 into contact with the atmosphere (air) as a refrigerant.
　As the cooling section 100A, it is also possible to use a heat exchanger to cool the treated water W1 gas, by heat exchange with the refrigerant liquid or the like. The refrigerant used in the heat exchanger may be any lower temperature at than treated water W1, for example, available at the site of the water treatment system 10, seawater (deep water), sewage, the use of sewage treatment water or the like it can.
　The intake pipe P1 through the treatment water W1, by cooling through the sea and the ground temperature is lower than the treatment water W1, it is also possible to configure the cooling section 100A.
　As the cooling section 100A, it is also possible to use a refrigerator or the like.
　Such cooling section 100A, for example, it is possible to cool the treated water W1 to 25 ~ 40 ° C..
[0032]
　In such water treatment system 10, it processes the treated water W1 as follows.
　Figure 2 is a diagram showing the flow of the water treatment process in water treatment systems.
(Step of introducing water to be treated)
　is first passed through a water intake pipe P1 by the pump 12, it is introduced into the water treatment system 10 to a predetermined temperature or more seawater as treated water W1 (step S1).
[0033]
(Cooling step of the water to be treated)
　treatment water W1 which has been introduced into the water treatment system 10 is cooled by the cooling section 100A (Step S2).
[0034]
(Filtration step)
　treated water is cooled in the cooling section 100A W1 passes through the raw water tank 11, a filtration device 21A through the connection pipe P2, 21B, is passed through the 21C. Treatment water W1 is a filtration device 21A, 21B, at 21C, is filtered through a filter material having a biofilm (step S3).
[0035]
(Desalination process)
　filtration device 21A, 21B, the treatment water W1 which has been filtered through 21C is pressurized by a high pressure pump 40, by being passed through the reverse osmosis membrane F of the reverse osmosis membrane device 51, salt (ion component) are removed and processed desalinated (step S4).
[0036]
　Thus, according to a first embodiment of water treatment system 10 and the water treatment method described above, the case of introducing the waste water above the predetermined temperature of the water to be treated W1, by cooling the treated water W1, reverse osmosis unit it is possible to suppress the damage to the reverse osmosis membrane F of 51 and 52. Thus, decrease in salt rejection of the reverse osmosis membrane F, it is possible to suppress the deterioration of the durability.
　Further, by cooling the treated water W1, it is possible to prevent the filtration device 21A, 21B, the growth rate of the organism to form the 21C biofilm decreases. This increases the growth rate of the biofilm, organic, particulate, adsorption of microorganisms, thereby improving the rate of degradation. Therefore, and concentration of organic substances, fine particles, microorganisms in the water to be treated W1, SDI (Silt Dencity Index: water quality indicators that are involved in occlusion of water treatment film), BFR (Biofilm Formation Rate: biofilms water treatment membrane surface water indicator), etc. to assess the risk of (biofilm) is improved. Suppressing a result, the filtration device 21A, 21B, it is possible to suppress a decrease in filtration performance in 21C, a reduction of flux (Flux) by suction or the like of biofouling and organic matter in the reverse osmosis unit 51, 52 on the downstream side be able to.
[0037]
　In the cooling section 100A, by cooling water to be treated W1 to 25 ~ 40 ° C., while suppressing damage to the reverse osmosis membrane F, filtration devices 21A, 21B, the growth rate of the organism to form the 21C biofilm decreases it can be suppressed.
[0038]
　Cooling section 100A cools the treated water W1 by heat exchange between the refrigerant water to be treated W1. With this configuration, it is possible to reliably cool the treated water W1.
[0039]
(First modification of the first embodiment)
　FIG. 3 is a diagram showing a configuration of a first modification of the water treatment system of the first embodiment.
　As shown in FIG. 3, the water treatment system 10, in addition to the configuration shown in the first embodiment, a temperature detector 101 for detecting the temperature of the water to be treated W1, treatment water detected by the temperature detection unit 101 W1 based on the temperature, so as to increase the supply amount of the refrigerant in the cooling section 100A in the case of more than the threshold temperature of the water to be treated W1 is predetermined, the amount of heat exchange between the water to be treated W1 and the refrigerant in the cooling section 100A and a control unit 102 for controlling the.
　The control device 102, and controls the ON / OFF such as cooling towers and heat exchangers which constitute a cooling unit 100A, by and controls the circulation amount of such refrigerant, the water to be treated W1 and the refrigerant in the cooling section 100A controlling the heat exchange amount of the.
[0040]
　In the example of FIG. 3, the temperature detector 101 are provided on the downstream side of the cooling section 100A, there is no intent to limit for that location. For example, it may be provided with a temperature detecting portion 101 on the upstream side of the cooling section 100A. Further, a temperature detection unit 101 may be provided in the preprocessing section 20 and just before or just after the desalination unit 50.
[0041]
　With this configuration, in accordance with the temperature of the for-treatment water W1 detected by the temperature detection unit 101, the controller 102 can automatically adjust the degree of cooling of the treated water W1 in the cooling section 100A . This makes it possible to reliably cool the treated water W1 in a proper temperature.
[0042]
(Second modification of the first embodiment)
　FIG. 4 is a diagram showing a configuration of a second modification of the water treatment system of the first embodiment.
　As shown in FIG. 4, the water treatment system 10, in addition to the configuration shown in the first embodiment, a temperature detection unit 101, a bypass passage 103 is provided with a flow regulating valve 104, a control unit 102B, the .
[0043]
　Bypass passage 103 is provided so as to bypass the cooling section 100A. Flow control valve 104 is provided in the bypass passage 103 to adjust the flow rate distribution possible treatment water W1 bypass passage 103.
　Controller 102B based on the temperature of the for-treatment water W1 detected by the temperature detection section 101, if less than the threshold temperature of the water to be treated W1 is predetermined to control the flow control valve 104, the bypass passage 103 reducing the flow rate of the for-treatment water W1 to be circulated.
[0044]
　With such a configuration, depending on the temperature of the water to be treated W1 detected by the temperature detection unit 101, by circulating the treatment water W1 in a bypass passage 103 bypassing the cooling unit 100A, the through cooling section 100A by reducing the flow rate of the treated water W1, reduce the amount of cooling water to be treated W1.
　Further, when the temperature of the water to be treated W1 is equal to or higher than the threshold, to reduce the flow rate of the for-treatment water W1 to flow into the bypass passage 103 to increase the flow rate of the for-treatment water W1 through the cooling section 100A, the water to be treated increasing the amount of cooling W1. In this way, the temperature of the cooling water, and adjust the flow rate of the for-treatment water W1 for cooling in the cooling section 100A, it is possible to adjust the treatment water W1 in a proper temperature.
[0045]
(Third modification of the first embodiment)
　FIG. 5 is a diagram showing a configuration of a third modification of the water treatment system of the first embodiment.
　As shown in FIG. 5, water treatment system 10, in addition to the configuration shown in the first embodiment, the bypass passage 103, the flow control valve 104, includes a heating unit 105 for heating the treatment water W1, the there.
　Heating unit 105, for example, to heat medium and the heat exchange by the heat exchanger and the method for heating the treatment water W1, by blowing hot steam, systems for performing the heat treated water W1, various heating It can be adopted the method.
[0046]
　In such a configuration, it is possible to the temperature of the water to be treated W1, or by heating the water to be treated W1 or cooled in the cooling section 100A, a heating unit 105.
[0047]
(Second Embodiment)
　Next, description will discuss a second embodiment of the water treatment system and a water treatment method according to the present invention. In the second embodiment described below, only the structure of the cooling unit first embodiment is different, as well as will be denoted by the same reference numerals in the first embodiment and the same parts, without redundant description.
[0048]
　Figure 6 is a schematic diagram showing the construction of a water treatment system in the second embodiment.
　As shown in FIG. 6, the water treatment system 10 in this embodiment, as the cooling section 100B, and a seawater supply passage 110 for mixing seawater W4 taken from the ocean water to be treated W1.
　Seawater supply path 110 is on-off valve or a flow regulating valve 111 is provided, can be carried out whether the introduction of seawater W4, or adjustment of the introduction amount of seawater W4.
[0049]
　In such a configuration, open the on-off valve or flow control valve 111, a low-temperature seawater W4 than treatment water W1, by mixing the seawater W4 to the water to be treated W1, lowering the temperature of the water to be treated W1 be able to.
[0050]
　Therefore, according to a second embodiment of water treatment system 10 and the water treatment method described above, the case of introducing the waste water above the predetermined temperature of the water to be treated W1, to cool the treated water W1 by mixing seawater W4 it can.
　Thus, it is possible to suppress the damage to the reverse osmosis membrane F of the reverse osmosis unit 51. Therefore, reduction of the salt rejection of the reverse osmosis membrane F, it is possible to suppress the deterioration of the durability.
　Further, by cooling the treated water W1, it is possible to prevent the filtration device 21A, 21B, the growth rate of the organism to form the 21C biofilm decreases. Thus, it is possible to suppress the filtration device 21A, 21B, a reduction in filtration performance in 21C.
　As a result, even when the temperature of the water to be treated W1 is high, the water treatment system 10, can exhibit high performance.
[0051]
(Third Embodiment)
　Next, a description is given of a third embodiment of the water treatment system and a water treatment method according to the present invention. In a third embodiment described below, first, only the structure of the cooling unit the second embodiment is different, as well as will be denoted by the same reference numerals to the first, the same portions as the second embodiment, duplicate description thereof will be omitted.
[0052]
　Figure 7 is a schematic diagram showing the construction of a water treatment system in the third embodiment.
　As shown in FIG. 7, the water treatment system 10 in this embodiment, in addition to the same configuration as the first embodiment, as the cooling section 100C, and a reflux path 120, the concentrated water cooling unit 121, a reflux water adjusting unit 123 further comprising the, temperature detecting unit 101, a concentrated water temperature detector 124, and the reflux water control unit 125, a.
[0053]
　Return path 120, the concentrated water W3 discharged from the second-stage reverse osmosis membrane device 52 than the reverse osmosis membrane apparatus 52 flows back to the upstream side. In this embodiment, the reflux path 120 is refluxed cooled concentrated water W3 in concentrated water cooling unit 121, a filtration device 21A, 21B, on the upstream side than 21C.
[0054]
　Concentrated water cooling unit 121, the refrigerant and concentrated water W3 flowing return path 120 for cooling the concentrated water W3 by heat exchange.
　Reflux water adjusting unit 123 is a flow regulating valve provided in the reflux passage 120, to adjust the flow rate of the concentrated water W3 is refluxed at the reflux path 120 is cooled by the condensed water cooling unit 121.
　Temperature detection unit 101 detects the temperature of the water to be treated W1 flowing intake tube P1. Concentrated water temperature detector 124 detects the temperature of the concentrated water W3.
[0055]
　Reflux water control unit 125, based on the temperature of the water to be treated W1 detected by the temperature detection unit 101, and the temperature of the concentrated water W3 detected by concentrated water temperature detector 124, the reflux path at reflux water adjusting unit 123 controlling the flow rate of the concentrated water W3 to reflux at 120.
[0056]
　In such a configuration, refluxed for concentrated water W3 cooled by the condensed water cooling unit 121 is discharged from the reverse osmosis unit 52 on the upstream side of the reverse osmosis unit 52, by mixing with the water to be treated W1, it is possible to lower the temperature of the water to be treated W1.
　Furthermore, it is possible to adjust the temperature of the water to be treated W1, depending on the temperature of the concentrated water W3, the amount of concentrated water W3 to reflux at reflux passage 120 is mixed with the water to be treated W1, treatment water W1 it is possible to adjust the temperature properly.
[0057]
　Therefore, according to the third embodiment water treatment system and a water treatment method described above, reflux retentate W3, that is mixed with water to be treated W1, it is possible to reduce the temperature of the water to be treated W1. Thus, it is possible to reduce the temperature of the water to be treated W1 of water flow filtration device 21A, 21B, to 21C and the reverse osmosis unit 52.
　Furthermore, it is possible to suppress the damage to the reverse osmosis membrane F of the reverse osmosis membrane device 51, reduction of the salt rejection of the reverse osmosis membrane F, it is possible to suppress the deterioration of the durability. Further, by cooling the treated water W1, filtration devices 21A, 21B, growth rate of the organism to form the 21C biofilm can be suppressed from being lowered. Thus, it is possible to suppress the filtration device 21A, 21B, a reduction in filtration performance in 21C.
　As a result, even when the temperature of the water to be treated W1 is high, the water treatment system 10, can exhibit high performance.
[0058]
(First Modification of Third Embodiment)
　In a third embodiment, the return path 120, have been concentrated water W3 cooled with concentrated water cooling unit 121, a filtration device 21A, 21B, so as to reflux the upstream side of the 21C It was in, but the present invention is not limited to this.
　Figure 8 is a diagram showing the configuration of a water treatment system according to a first modification of the third embodiment.
　As shown in FIG. 8, return path 120, the concentrated water W3 cooled in concentrated water cooling unit 121, a filtration device 21A, 21B, may be refluxed between 21C and reverse osmosis unit 52.
　Thus, the cooled concentrated water W3 filtration device 21A, 21B, if caused to reflux between 21C and reverse osmosis unit 52, lowering the temperature of the water to be treated W1 which passed through the reverse osmosis unit 52 it can be.
[0059]
(Second Modification of Third Embodiment)
　FIG. 9 is a diagram showing the configuration of a water treatment system in the second modification of the third embodiment.
　As shown in FIG. 9, the reflux path 120, the concentrated water W3, filtration devices 21A, 21B, and upstream of 21C, filtration devices 21A, 21B, and between 21C and reverse osmosis unit 52, both in the it may be allowed to reflux, respectively. In this case, the return path 120, a filtration device 21A, 21B, 21C and reverse osmosis membrane and the return pipe 120A for circulating concentrated water W3 between the device 52, a filtration device 21A, 21B, concentrate on the upstream side of the 21C W3 the it is sufficient to branch to the return pipe 120B to reflux. Further in this case, return path 120A, preferably provided with a reflux water adjusting unit 123 to the respective 120B.
　With this configuration, return channel 120A, each of reflux water adjusting unit 123 120B, it is possible to adjust return channel 120A, the flow rate of the concentrated water W3 is recirculated through 120B individually. Therefore, filtration device 21A, 21B, 21C, and the concentrated water W3 is mixed to the water to be treated W1 at each upstream of a reverse osmosis membrane device 52, the treatment water W1, filtration devices 21A, 21B, 21C, reverse osmosis it can be supplied with cooling to a temperature suitable for each membrane unit 52. For example, in the intake phase in the intake pipe P1, and for example, the treatment water W1 was 45 ° C., filtration device 21A, 21B, for example, 37 ° C. by mixing the concentrated water W3 in the previous 21C, the reverse osmosis unit 52 in the immediately preceding, it is possible, as adjusted to 35 ° C..
[0060]
(Other Modifications)
　The present invention is not limited to the embodiments described above, without departing from the scope of the invention include those in which various modifications to the embodiments described above. That is, the specific shapes and configurations such as listed in embodiment merely examples and can be appropriately changed.
　For example, the number of connecting the filtration apparatus 21 parallel, in series, can be changed as appropriate.
[0061]
　Further, in the embodiments described above, the pre-processing unit 20 has been described as an example a case where a biofilm. However, the pre-processing unit 20 is not limited to the case where a biofilm. Furthermore, a case has been described which performs Mukusurichu pretreatment to an example, it may be a configuration for performing filtering in preprocessing desalting treatment may be pretreated non Mukusurichu pretreatment.
[0062]
　Furthermore, as the desalination process unit 50, a configuration including a reverse osmosis membrane device 51 is not limited to this. Only the reverse osmosis membrane device 51 may be provided in desalination unit 50.
　Further, a cooling section 100A of the first embodiment, the cooling section 100B of the second embodiment, the cooling section 100C of the third embodiment may be used in combination as appropriate.
Industrial Applicability
[0063]
　This invention sea water can be applied to water treatment systems and water treatment method for processing desalination. According to the water treatment system and a water treatment method, even when the temperature of the water to be treated is high, it can exhibit high performance.
DESCRIPTION OF SYMBOLS
[0064]
10 water treatment system
11 the raw water tank
12 pump
13 drain tank
14 water tank
20 pre-processing unit
21A, 21B, 21C filtering device
21f filter unit
30 cartridge filter
40 the high-pressure pump
50 desalination unit
51 reverse osmosis unit
60 energy recovery device
61,62 rotor
100A cooling unit (the cooling water cooling
unit) 100B, 100C cooling unit
101 temperature detector
102,102B controller
103 bypass
104 flow rate adjusting valve
105 heating unit
110 seawater supply path
111 flow control valve
120,120A , 120B return path
121 concentrated water cooling unit
123 reflux water adjusting unit
124 concentrated water temperature detecting unit
125 reflux water controller
F reverse osmosis membrane
P1 intake pipe (drain introduction
unit) P2, P3, P4, P5, P6, P7, P8, P9, P12 connected zoku pipe
P10 pipe connected zoku
W1 is treated water
W2, W3 concentrated water
W4 seawater

The scope of the claims
[Requested item 1]
A drain inlet portion for introducing a predetermined temperature or more waste water as water to be treated,
and the reverse osmosis membrane apparatus for separating the treated water from the drainage inlet portion and concentrated water and fresh water,
　supplied to the reverse osmosis unit a cooling unit for cooling the water to be treated
a water treatment system comprising a.
[Requested item 2]
　The reverse osmosis is provided on an upstream side of the membrane device, further comprising a filtering device with respect to the for-treatment water subjected to filtration treatment with filter medium layers biofilm formed
water treatment system of claim 1.
[Requested item 3]
　The cooling unit, the water treatment system according to claim 1 or 2 comprising the treatment water cooling unit for cooling the water to be treated by causing the water to be treated and the refrigerant exchange heat.
[Requested item 4]
　A temperature detector for detecting the temperature of the water to be treated,
　said detected by the temperature detection unit based on the temperature of the water to be treated, the in the treatment water cooling unit when the temperature of the water to be treated is equal to or larger than the threshold a control device for increasing control the supply amount of the refrigerant
water treatment system of claim 3, comprising a.
[Requested item 5]
　A temperature detector for detecting the temperature of the water to be treated,
　the cooling unit bypass passage provided so as to bypass a
　flow regulating valve for regulating the flow rate of circulation can be the treated water to the bypass passage,
　the detected by the temperature detection unit based on the temperature of the water to be treated, wherein when the temperature of the water to be treated is not less than the threshold value, controls the flow rate adjusting valve, the flow rate of the treated water to be circulated in the bypass passage a control device for reducing the
water treatment system according to claim 3 or 4 comprising a.
[Requested item 6]
　The cooling unit, water treatment system according to claim 1, any one of 5 with a seawater supply passage for mixing seawater taken from the ocean into the water to be treated.
[Requested item 7]
　The water treatment system according to any one of claims 1 to 6, further comprising a heating unit for heating the water to be treated.
[Requested item 8]
　The cooling unit includes
　a return path for returning concentrated water discharged from the reverse osmosis membrane device upstream of the reverse osmosis unit,
　said bringing the concentrated water and the refrigerant heat exchanger flowing through the return passage a concentrated water cooling unit for cooling the concentrated water by
the water treatment system according to any one of claims 1 to 7 comprising a.
[Requested item 9]
　The return path, the concentrated water that has been cooled by the concentrated water cooling unit, and between the filtering device and the reverse osmosis membrane apparatus, in claim 8 for recirculating at least one of the upstream side of the filtration device the water treatment system described.
[Requested item 10]
　Is cooled by the concentrated water cooling unit, and a reflux water adjusting unit for adjusting the flow rate of the concentrated water refluxing in the return path,
　the temperature detecting section for detecting the temperature of the water to be treated,
　detects the temperature of the concentrated water a concentrated water temperature detection unit, for
　the return channel on the basis of the temperature of the concentrated water that has been detected by the temperature and the concentrated water temperature detecting portion of the water to be treated detected by the temperature detecting unit, in the return water amount adjustment unit in a refluxing water control unit, for controlling the flow rate of the concentrated water flowing back
water treatment system according to claim 8 or 9 further comprising a.
[Requested item 11]
　The cooling unit, water treatment system according to claim 1, any one of 10 to cool the water to be treated 25 ~ 40 ° C..
[Requested item 12]
　Introducing a predetermined temperature or more of the water to be treated,
　a step of cooling the water to be treated is introduced,
　the cooled the water to be treated, a step of separating into a concentrated water and fresh water
water treatment comprising Method.