JP2014094359A - Water treatment system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treatment system capable of homogenizing the distribution of flow rates of water destined to multiple membrane modules connected in parallel.SOLUTION: The water treatment system of the present invention is a water treatment system U1 using a membrane module 12 for filtering water and a pressure vessel 11 into which the membrane module 12 is inserted in a state where multiple pressure vessels 11 are being connected in parallel via pipelines and possessing, on the upstream side of the membrane module 12 within each pressure vessel 11, tabular resistors 1 and 2 mobilized in a direction perpendicular to the streaming direction of fed yet-to-be-treated water w1 and bestowing a variable resistance onto the yet-to-be-treated water w1 so as to increase or decrease the flow rate thereof.

Description

  The present invention relates to a membrane module device that draws filtered water from supply water, and more particularly to a water treatment system including membrane module devices arranged in parallel.

Conventionally, there are the following patent documents 1 to 3 as known literature inventions related to a configuration in which membrane module devices for obtaining filtered water from supply water are arranged in parallel.
Patent Document 1 discloses a configuration of a water treatment system in which a plurality of reverse osmosis membrane modules are connected in parallel.

  In Patent Document 2, in a water treatment system in which a plurality of membrane modules are connected in parallel, a valve is installed in the supply water inflow pipe of each membrane module, and the fluid resistance is adjusted by the opening degree of each valve. The structure which adjusts the inflow flow rate to is disclosed.

  Patent Documents 1 and 2 disclose a configuration of an end port connection system in which a membrane module is inserted into a pressure vessel, a pipe is connected to an upstream end face of the pressure vessel, and they are connected to one header pipe. Yes.

On the other hand, for example, Patent Document 3 discloses a side port connection method, that is, a method in which a pipe is connected to a side surface of a pressure vessel and the pressure vessels are connected by a pipe.
Patent document 3 is the structure which inserts a membrane module in the pressure vessel of a side port connection system. Unlike the end port connection method, the side port connection method does not require the header pipe for feed water and concentrated water used in the end port connection method, so the amount of piping can be reduced compared to the end port connection method. .

  Since supply water and concentrated water have high salinity, it is necessary to use high-cost pipes with corrosion resistance for the pipes through which they flow. Therefore, the side port connection method has a lower cost and a cost advantage than the end port connection method.

JP 2007-229718 A JP 2007-209947 A JP 2003-294143 A

  By the way, in the case where the membrane modules described in Patent Document 1 are connected in parallel, each membrane module is caused by the fluid resistance of the pipe connecting the pump and each membrane module or the change in fluid resistance with the passage of time of the membrane module. The distribution of the supply water flow is not uniform.

  In this case, the reverse osmosis membrane module is also unevenly deteriorated due to variations in the water pressure of the pressure vessel due to the uneven flow distribution to each membrane module. This deterioration is a phenomenon caused by clogging of the membrane due to organic matter or microorganisms, and means that, for example, the supply water pressure necessary to maintain a certain permeate flow rate increases.

  When the deterioration has progressed to some extent, the membrane module is replaced or cleaned. However, due to the configuration of the apparatus, the replacement or cleaning of the membrane module is performed at once for all the membrane modules connected in parallel. Therefore, even if the membrane module is deteriorated to such an extent that it is not necessary to replace it and can continue the operation of the water treatment, the membrane module is replaced or cleaned, which is inefficient in terms of cost. .

  To eliminate this inefficiency, it is necessary to equalize the flow distribution of the membrane modules connected in parallel. In order to make the inflow distribution to each membrane module uniform, a valve is inserted into a pipe for supplying water to each membrane module described in Patent Document 2, and the fluid resistance is adjusted by adjusting the opening of the valve. There is a way to do it. In this configuration, construction for connecting the valve and the piping is necessary, and the construction period of the plant becomes longer than when no valve is provided.

  Moreover, the flow rate equalization by insertion of the valve described in Patent Document 2 can be applied only to the end port connection method. In the side port connection system, the pressure vessel of the upstream membrane module is sequentially connected to the pressure vessel of the downstream membrane module by piping, so there is no means for adjusting the flow rate of the supply water to the pressure vessels connected in parallel. Therefore, when the number of pressure vessels connected in parallel is increased, the distribution of the flow rate of the supply water to each pressure vessel is increased. That is, while flowing into the upstream membrane module at a large flow rate, it flows into the downstream membrane module at a small flow rate. Therefore, in the side port connection method, there is a limit to the number of pressure vessels that can be connected in parallel.

On the other hand, the flow distribution in the initial state of the plant is made uniform by changing the shape such as the diameter and length of the pipe connected from the pump to each membrane module so that the fluid resistance to each membrane module is uniform. This can also be realized by making the fluid resistance from each of the membrane modules uniform.
However, this method cannot cope with the temporal change of fluid resistance accompanying the deterioration of the membrane module.

  In view of the above circumstances, an object of the present invention is to provide a water treatment system capable of distributing the flow rate to a plurality of membrane modules connected in parallel and equalizing fluid resistance.

  In order to achieve the above object, a water treatment system according to the present invention includes a membrane module that performs water filtration, a pressure vessel in which the membrane module is inserted, and a plurality of the pressure vessels connected in parallel via a pipe. A water treatment system that moves upstream of the membrane module in the pressure vessel along a direction perpendicular to the flow direction of the untreated water to be supplied, thereby providing variable resistance to the untreated water. And a plate-like resistor for increasing or decreasing the flow rate.

  ADVANTAGE OF THE INVENTION According to this invention, the water treatment system which can aim at the distribution of the flow volume to the some membrane module connected in parallel, and equalization of fluid resistance is realizable.

It is a figure which shows the structure of the seawater desalination plant of a reverse osmosis system which is one of the application objects of this invention. It is a top view which shows the structure of the reverse osmosis unit of the end port connection system which connects piping to the end surface of each pressure vessel of Embodiment 1 concerning this invention, and connects each pressure vessel in a cross section. (a) is sectional drawing of the one end part side of an end port pressure vessel which shows the structure which applied two movable and fixed perforated plates to an end port pressure vessel, (b) is an A direction arrow view of (a). It is a figure and (c) is the BB sectional drawing of (a). (a) is a front view of a movable perforated plate, (b) is a sectional view taken along the line CC of (a). (a) is a front view of a fixed perforated board, (b) is the DD sectional view taken on the line of (a). (a) is a front view of the movable / fixed perforated plate showing the case where the flow path is fully opened, and (b) is a front view of the movable / fixed perforated plate showing the case where the flow path is partially opened. It is the figure which compared supply water flow volume with the case where there is no resistor of a comparative example, and the case where there is a resistor of Embodiment 1 in a plurality of end port pressure vessels connected in parallel. It is sectional drawing which shows the flow line and flow velocity distribution of the supply water in the one end part of the end port pressure vessel of a comparative example (conventional). It is sectional drawing which shows the flow line and flow velocity distribution of the supply water in the one end part of the end port pressure vessel of Embodiment 1. It is a figure which shows the flow of the organic substance and microorganisms to a reverse osmosis membrane module when a porous body exists in the end port pressure vessel of a deformation | transformation form. It is a figure which shows the flow of the organic substance and microorganisms to a reverse osmosis membrane module when there is no porous body in the end port pressure vessel of a comparative example. It is a top view which shows the structure of the reverse osmosis unit of the side port connection system which connects piping to the side surface of the side port pressure vessel of Embodiment 2, and connects each side port pressure vessel in a cross section. It is sectional drawing of the one end part side of the side port pressure vessel which shows the structure which applied the two movable and fixed perforated plates to the side port pressure vessel of Embodiment 2. (a) is the figure which made the overlapping area | region of the hole of the movable perforated plate of modification 1 and the hole of a fixed perforated plate into the fully open state, (b) is the hole of a movable perforated plate, and the hole of a fixed perforated plate FIG. (a), (b) is one of the holes of the movable perforated plate and the holes of the fixed perforated plate of the modified embodiment 2 as a long hole along the circumference around the rotation center, and the other is in the radial direction from the long hole. (A) shows a fully closed state, and (b) shows a partially open state.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
The present invention provides a seawater desalination plant that obtains fresh water such as drinking water and industrial water from seawater, a water treatment plant that produces drinking water, a sewage treatment plant that purifies sewage sewage, and industrial wastewater so as to suit the environment. Any water treatment system using a membrane module such as an industrial wastewater treatment plant to be treated can be applied.

Hereinafter, although the form for implementing this invention is mentioned taking a seawater desalination plant as an example, the application object of this invention is not limited to a seawater desalination plant.
FIG. 1 shows the configuration of a reverse osmosis seawater desalination plant which is one of the objects to which the present invention is applied.
The configuration of a reverse osmosis seawater desalination plant P will be described with reference to FIG.
The seawater desalination plant P of the embodiment has passed the intake section 1A that draws seawater from the sea, the pretreatment section 1B that removes particles in the drawn seawater and organic substances having a relatively high molecular weight, and the pretreatment section 1B. And a desalting unit 1C that mainly removes ions from seawater.

The intake section 1A includes an intake pump 111 that draws seawater from the sea, and an intake tank 112 that stores the pumped seawater.
The pre-processing unit 1B has various configurations depending on the components of seawater, but the configuration shown in FIG. 1 is an example thereof and includes the following configuration.
The pretreatment unit 1B includes a multi-layer filtration module pump 121 that supplies pumped seawater, a multi-layer filtration module 122 that filters the supplied seawater in two or more layers, and a multi-layer filtered seawater that is supplied to the subsequent stage. And an outer filtration membrane module pump 123. Furthermore, the pretreatment unit 1B includes an ultrafiltration membrane module 124 that filters the seawater after the multi-layer filtration with an ultrafiltration membrane, and a desalting salt that stores the pretreated seawater that has passed through the ultrafiltration membrane module 124. Part supply water tank 125.

The desalination unit 1C has various configurations depending on the components of the seawater as in the pretreatment unit 1B, and the configuration shown in FIG. 1 is an example, and includes the following configuration.
The desalination unit 1C is a reverse osmosis having a high pressure pump 131 that supplies pretreated seawater (feed water w1) at a high pressure, and a plurality of reverse osmosis membrane modules that reversely osmose the pretreated high pressure seawater to make it desalinated. A unit U1 and a permeate tank 135 that stores permeate w2 that has permeated through the reverse osmosis unit U1 and has a reduced ion concentration are provided.
In addition, the desalting unit 1C collects the kinetic energy of the concentrated water tank 134 that stores the concentrated water w3 that does not pass through the reverse osmosis unit U1 and the ion concentration has increased, and the concentrated water that flows into the concentrated water tank 134. And a power recovery device 133 that uses energy for boosting the feed water w1 to the reverse osmosis unit U1.
The present invention is applied to the reverse osmosis unit U1.

  Next, Embodiment 1 in which the present invention is applied to a reverse osmosis unit using an end port connection type pressure vessel will be described with reference to FIGS.

<< Embodiment 1 >>
FIG. 2 is a top view showing in cross section the configuration of an end port connection type reverse osmosis unit in which piping is connected to the end face of each pressure vessel according to the first embodiment of the present invention to connect each pressure vessel.
In the reverse osmosis unit U1 of the end port connection method, the feed water w1 to each reverse osmosis membrane module 12 is connected from the upstream feed water header pipe 15 to one end 11a of each end port pressure vessel 11. The feed water pipes 16 are distributed to the respective end port pressure vessels 4.

The supply water w1 flowing into the end port pressure vessel 11 is adjusted to a predetermined flow rate by a resistor t (movable / fixed porous plates 1 and 2 described later), passes through the resistor t, and flows into the reverse osmosis membrane module 12. . A part of the supply water w1 flowing into the reverse osmosis membrane module 12 permeates the semipermeable membrane of the reverse osmosis membrane module 12 and is filtered to become permeated water w2, and the permeated water w2 flows into the water collecting pipe 13. The permeated water w <b> 2 that has flowed into the water collecting pipe 13 of each end port pressure vessel 11 joins the permeated water pipe 14.
On the other hand, the concentrated water w3 whose ion concentration has increased as a result of membrane exchange in the reverse osmosis membrane module 12 in the supply water w1 flowing into the endport pressure vessel 11 is connected to the other end 11b of the endport pressure vessel 11. The concentrated water flows into the concentrated header pipe 17 through the concentrated water pipe 18 and joins.

<Movable porous plate 1 and fixed porous plate 2 of resistor t>
Next, the movable perforated plate 1 and the fixed perforated plate 2 of the resistor t that are arranged upstream of the reverse osmosis membrane module 12 in the end port pressure vessel 11 and adjust the flow rate will be described. FIG. FIG. 3B is a cross-sectional view of one end portion of the end port pressure vessel showing a configuration in which two movable / fixed perforated plates are applied to the end port pressure vessel, and FIG. FIG. 3C is a cross-sectional view taken along the line BB of FIG.

At one end 11a of the end port pressure vessel 11 shown in FIG. 3 (a), an end port pressure vessel end cap 41 that forms a lid on the one end 11a side is connected to a fastening member n such as a bolt at one end. It is fixed by inserting and screwing the hole of the pressure vessel end cap fixing jig 3 fixed to 11a.
Further, the end port pressure vessel 11 has one end portion 11 a at the upstream end of the reverse osmosis membrane module 12, the fixed perforated plate 2 fixed in the one end portion 11 a, and the user being rotated by the user to the reverse osmosis membrane module 12. A movable porous plate 1 that adjusts the flow rate together with the fixed porous plate 2 is disposed. The fixed perforated plate 2 is fixed to the end port pressure vessel 11 by a fastening member (not shown).

Fig.4 (a) is a front view of a movable perforated plate, FIG.4 (b) is CC sectional view taken on the line of Fig.4 (a). Fig.5 (a) is a front view of a fixed perforated plate, FIG.5 (b) is the DD sectional view taken on the line of Fig.5 (a).
The movable perforated plate 1 and the fixed perforated plate 2 are disk-like plate-like members in which a large number of holes 1a and 2a are perforated as shown in FIGS. However, it is only necessary to form a flow path for the feed water w1 by the hole 1a of the movable porous plate 1 and the hole 2a of the fixed porous plate 2, and the shape of these holes is not limited to the circular shape as shown in FIGS. For example, it may be oval or rectangular.

  As shown in FIG. 3 (b), the end port pressure vessel end cap 41 is a disk-shaped member having an outer diameter that is in close contact with the inner peripheral surface of one end portion 11a of the end port pressure vessel 11. An insertion hole 41a through which the water pipe 16 is inserted, and a long hole 41b through which the rotation handle 7 for gripping and operating the movable porous plate 1 by the user are perforated.

  The outer peripheral portion of the movable perforated plate 1 shown in FIG. 3A is fixed to one end portion of a cylindrical connecting member 4 that rotates along the inner peripheral surface of one end portion 11 a of the end port pressure vessel 11. Yes. A disk-shaped inner cap 6 having an outer diameter along the inner peripheral surface of the one end portion 11a of the end port pressure vessel 11 is fixed to the other end portion of the connecting member 4. A rotation handle 7 that is gripped when the user rotates the plate 1 is fixed. The rotation handle 7 is a member having a substantially U-shaped shape having a circular cross section.

In the inner cap 6 shown in FIG. 3C, a water collection pipe insertion hole 6a through which the water collection pipe 13 is inserted and a pipe insertion long hole 6b through which the supply water pipe 16 is inserted are drilled. The pipe insertion long hole 6b is a long hole so as not to be spatially buffered with the supply water pipe 16 when the inner cap 6 is rotated.
A water collecting pipe end cap 13 c is attached to one end of the water collecting pipe 13 to close the one end.
With this configuration, the user can rotate the movable perforated plate 1 by holding the rotating handle 7 and rotating it as indicated by arrows α1 and α2 in FIG.

  Materials such as movable perforated plate 1, fixed perforated plate 2, connecting member 4, end port pressure vessel end cap 41, pressure vessel end cap fixing jig 3, water collecting tube end cap 13c, inner cap 6, fastening member n Examples thereof include super stainless steel and glass fiber reinforced resin.

<Fluid resistance of feed water w1 by movable and fixed perforated plates 1 and 2>
Next, a method for adjusting the fluid resistance of the movable / fixed perforated plates 1 and 2 as the resistor t will be described.
FIG. 6 is a diagram for explaining a method of adjusting the fluid resistance by the two movable / fixed perforated plates 1 and 2, and FIG. 6 (a) is a diagram of the movable / fixed perforated plate showing the case where the flow path is fully opened. FIG. 6B is a front view of the movable / fixed perforated plate showing a case where the flow path is partially opened. That is, FIG. 6A shows a state where the flow path r of the supply water w1 formed by the hole 1a and the hole 2a is fully opened, and FIG. This is a partially opened state.

A fixed perforated plate 2 is fixed to one end portion 11 a of the end port pressure vessel 11. On the other hand, since the movable perforated plate 1 is fixed to the inner cap 6 via the connecting member 4, the inner cap 6 is rotated by applying an external force in the directions of arrows α1 and α2 in FIG. By doing so, the movable perforated plate 1 can be rotated.
Thereby, the movable porous plate 1 is rotated from the outside of the end port pressure vessel 11 to adjust the rotation angle of the movable porous plate 1, and in the overlapping region of the hole 1 a of the movable porous plate 1 and the hole 2 a of the fixed porous plate 2. The magnitude of the fluid resistance of the supply water w1 can be adjusted by changing the cross-sectional area of a certain flow path r.
At this time, the end port pressure vessel end cap 41 is marked with a rotation angle scale, while the rotation handle 7 is attached with a pointer, so that the rotation angle of the movable perforated plate 1 can be determined without using an angle measuring machine. Can be simplified.

  In the configuration shown in FIG. 3 (a), the supply water w1 passes through the supply water pipe 16 and flows into the end port pressure vessel 11, and is formed between the hole 1a of the movable porous plate 1 and the hole 2a of the fixed porous plate 2. It flows into the reverse osmosis membrane module 12 through the flow path r in the overlapping region (opening formed by the holes 1a and 2a). In this case, the frictional resistance, expansion resistance, and reduction resistance due to the flow path r in the overlapping portion of the hole 1a of the movable porous plate 1 and the hole 2a of the fixed porous plate 2 are the fluid resistance of the supply water w1 flowing into the reverse osmosis membrane module 12. It becomes.

<Measurement of clogging of reverse osmosis membrane module 12>
In order to measure the clogging of each reverse osmosis membrane module 12 due to a change over time, a conductivity sensor d as shown in FIG. 2 is provided downstream of each water collection pipe 13, and after the filtration process in each reverse osmosis membrane module 12 It is preferable to measure the conductivity of the permeated water w2 and manipulate the rotation angle of the movable perforated plate 1 of each end port pressure vessel 11 according to the conductivity of the permeated water w2. In FIG. 2, one conductivity sensor d is illustrated, but the conductivity sensor d is provided in each end port pressure vessel 11.

  Alternatively, each end port pressure vessel 11 is provided with a pressure sensor p1 for measuring the pressure of the supply water w1 flowing through the supply water pipe 16 and a pressure sensor p2 for measuring the pressure of the concentrated water w3 flowing through the concentrated water pipe 18. The difference between the pressure of the water w1 and the pressure of the concentrated water w3 may be obtained, and the rotation angle of the movable porous plate 1 of each end port pressure vessel 11 may be manipulated according to the difference.

  Note that the rotation angle of the movable perforated plate 1 is automatically operated using a motor such as a stepping motor or a speed reduction mechanism, and the conductivity of the permeated water w2, the pressure of the supply water w1, and the pressure of the concentrated water w3. May be obtained by a control means such as a microcomputer or a controller, and the rotation angle of the movable porous plate 1 may be automatically operated by the control means in accordance with the difference in conductivity or pressure.

  According to the first embodiment, the flow rate of the supply water distributed to the reverse osmosis membrane module 12 in the end port pressure vessel 11 connected in parallel can be made uniform. That is, since the fluid resistance from the pump (high-pressure pump 131) to each reverse osmosis membrane module 12 can be adjusted for each reverse osmosis membrane module 12 after the plant construction, the fluid resistance accompanying the deterioration of the reverse osmosis membrane module 12 It is possible to cope with changes over time.

FIG. 7 is a diagram comparing the supply water flow rate in the case where there is no comparative example (conventional) resistor and in the case where the resistor t of the first embodiment is present in a plurality of end port pressure vessels connected in parallel. . The horizontal axis of FIG. 7 shows each end port pressure vessel, and the vertical axis of FIG. 7 shows the supply water flow rate of each end port pressure vessel.
As shown in FIG. 7, the number of end port pressure vessels 11 connected in parallel is four, and each of the No. 1, no. 2, No. 3, no. In the case of 4, the supply water flow rate flowing into each of the end port pressure vessels in the comparative example varies when the supply water flow rate flowing into each end port pressure vessel varies.

  On the other hand, when the movable / fixed porous plates 1 and 2 of the resistor t are inserted into the end port pressure vessel 11, each end is adjusted by rotating the movable porous plate 1 and adjusting the flow path r. The flow rate of the supply water flowing into the port pressure vessel 11 can be made uniform (equal). At this time, since there is no need to connect a flow rate adjusting valve to the supply water pipe 16, it is possible to shorten the construction period and reduce the maintenance and management costs of the pipe.

  In addition, by adopting a structure in which the fluid resistance of the resistor t (movable / fixed perforated plates 1, 2) can be adjusted from the outside of the end port pressure vessel 11 by the rotation handle 7, The fluid resistance of the resistor t can be adjusted according to the change in resistance. In this way, the fluid resistance from the resistor t (movable / fixed perforated plate 1, 2) to each reverse osmosis membrane module 12 can be made uniform, and the flow rate of the supply water w1 flowing into each end port pressure vessel 11 can be made uniform.

8 and 9, the effect of rectification inside the end port pressure vessel 11 by the configuration of the resistor t using the two movable porous plates 1 and the fixed porous plate 2 shown in FIGS. explain.
FIG. 8 is a cross-sectional view showing the streamlines and flow velocity distribution of the feed water in one end of the comparative example (conventional) end port pressure vessel. FIG. 9 is a cross-sectional view showing the flow line and flow velocity distribution of the supply water in one end of the end port pressure vessel of the first embodiment.

  In the configuration in which there is no resistor inside the end port pressure vessel 211 shown in FIG. 8 of the comparative example, the inertial force of the feed water w1 inside the feed water pipe 206 is not reduced in the space 211k inside the end port pressure vessel 211. The radial flow velocity distribution of the feed water w1 flowing into the reverse osmosis membrane module 202 is larger near the feed water inlet 211i than near the feed water outlet 211o.

On the other hand, in the configuration in which the movable perforated plate 1 and the fixed perforated plate 2 as the resistor t are inserted upstream of the reverse osmosis membrane module 12 inside the end port pressure vessel 11 shown in FIG. become that way.
Of the supply water w1 that collides with the movable porous plate 1 due to the inertial force of the supply water w1 inside the supply water pipe 16, the supply water w1 flowing toward the hole 1a portion of the movable porous plate 1 is the hole 1a and the fixed porous plate. 2 flows through the reverse osmosis membrane module 12 through the flow path r in the overlapping region (opening formed by the holes 1a and 2a) with the two holes 2a. On the other hand, the feed water w1 that collides with a portion other than the overlapping region of the hole 1a of the movable perforated plate 1 and the hole 2a of the fixed perforated plate 2 cannot flow into the reverse osmosis membrane module 12 and in the space 11k inside the end port pressure vessel 11 It contributes to the water pressure rise in the space 11k.

As a result, the flow velocity distribution in the radial direction of the feed water w1 flowing into the reverse osmosis membrane module 12 is made uniform by the water pressure in the space 11k (see the flow velocity distribution on the right in FIG. 9).
Accordingly, the reverse osmosis membrane in the reverse osmosis membrane module 12 can be used evenly, and therefore the reverse osmosis membrane module 12 compared to the case of the resistor t (movable / fixed perforated plates 1 and 2) of FIG. 8 of the comparative example. Deterioration of is suppressed.

<< Modified form >>
FIG. 10 is a diagram showing the flow of organic matter and microorganisms to the reverse osmosis membrane module when a porous body is present in the modified end port pressure vessel.
In the reverse osmosis unit U1 of the first embodiment, the modified embodiment includes a porous body g1 that removes organic substances and microorganisms bi contained in the supply water w1.
In a modified embodiment, a porous body g1 that removes organic matter and microorganisms contained in the feed water w1, for example, an ultrafiltration membrane having a pore diameter of 1 μm or less, is provided between the movable porous plate 1 and the fixed porous plate 2 to provide organic matter. And microorganisms bi are trapped in the porous body g1 and the penetration into the reverse osmosis membrane module (element) 12 is suppressed.

FIG. 11 is a diagram showing the flow of organic matter and microorganisms to the reverse osmosis membrane module when there is no porous body in the end port pressure vessel of the comparative example.
In the conventional configuration in which there is no porous body inside the end port pressure vessel 211 of FIG. 11 of the comparative example, the reverse osmosis membrane module 202 has permeated the pretreatment part or the desalination part supply water tank 125 (see FIG. 1). Organic matter and microorganisms bi generated inside enter. As a result, the reverse osmosis membrane module 202 may be clogged with organic matter and microorganisms bi.

  On the other hand, in the modified embodiment, as shown in FIG. 10, a porous body g1, for example, an ultrafiltration membrane having a pore diameter of 1 μm or less is inserted upstream of the reverse osmosis membrane module 12 inside the end port pressure vessel 11. Organic substances and microorganisms bi can be trapped in the porous body g1 to prevent infiltration into the reverse osmosis membrane module (element) 12.

When the degree of clogging of the porous body g1 becomes large, either the porous body g1 is replaced, or the porous body is washed (backwashed) by flowing a cleaning solution from the concentrated water pipe 17 side (see FIG. 2). Restore the capture function of g1.
According to this configuration, the organic matter and microorganisms bi contained in the supply water w1 are captured by the configuration having the porous body g1 in the end port pressure vessel 11, and clogging of the reverse osmosis membrane module 12 is suppressed. The deterioration of the reverse osmosis membrane module 12 is suppressed as compared with the case where the porous body g1 is not provided.

In the modified embodiment, the case where the porous body g1 is provided between the movable porous plate 1 and the fixed porous plate 2 is exemplified, but the end port pressure vessel other than between the movable porous plate 1 and the fixed porous plate 2 is exemplified. 11 may be provided on the upstream side of the reverse osmosis membrane module 12.
Moreover, although the ultrafiltration membrane was illustrated as a porous body g1 in the deformation | transformation form, you may use another membrane.

<< Embodiment 2 >>
FIG. 12 is a top view showing in cross section the configuration of a reverse osmosis unit of a side port connection system in which a pipe is connected to the side surface of the side port pressure vessel of Embodiment 2 to connect each side port pressure vessel.
In the second embodiment, a movable perforated plate 31 and a fixed perforated plate 3 similar to the movable perforated plate 1 and the fixed perforated plate 2 described in the first embodiment are added to the reverse osmosis unit U2 using the side port pressure vessel 21 of the side port connection type. It is applied.

In the reverse osmosis unit U2 of the end port connection method of the second embodiment, the supply water w1 to the reverse osmosis membrane module 22 passes through the high-pressure pump 131 (see FIG. 1) of the desalination unit 1C and is supplied to the side port connection. The distribution pipe 29 distributes to the side port pressure vessels 21 through the side port connection supply water piping 21 h connected to the side surface of the side port pressure vessel 21.
The feed water w1 flowing into the side port pressure vessel 21 passes through the flow path formed by the overlapping region of the hole 31a of the movable porous plate 31 that is a resistor and the hole 32a of the fixed porous plate 32, and then the reverse osmosis membrane module. 22 flows in.

  A part of the supply water w 1 flowing into the reverse osmosis membrane module 22 passes through the reverse osmosis membrane module 22 to become permeate water w 2 and flows into the water collecting pipe 23. The permeated water w <b> 2 flowing through the water collecting pipe 23 of each side port pressure vessel 21 joins the permeated water pipe 24. The concentrated water w3 having an increased ion concentration without passing through the reverse osmosis membrane module 22 passes through the side port pressure vessel concentrated water piping 28a connected to the side surface of the side port pressure vessel 21, and is concentrated in the side port connection. It flows into the piping 28b for work.

FIG. 13 is a cross-sectional view of the side port pressure vessel on one end side showing a configuration in which two movable / fixed perforated plates are applied to the side port pressure vessel of the second embodiment.
Next, a configuration using two movable / fixed perforated plates 31 and 32 as resistors inserted into the side port pressure vessel 21 and a method for adjusting the fluid resistance of the movable / fixed perforated plates 31 and 32 will be described. .

In the configuration shown in FIG. 13, the movable perforated plate 31 and the fixed perforated plate 32 are plate-like members in which a large number of holes 31a and 31b similar to those shown in FIGS.
Here, it is sufficient that the flow path for the supply water w1 can be formed by the hole 31a of the movable porous plate 31 and the hole 32a of the fixed porous plate 32. The shape of these holes is circular as shown in FIGS. For example, an elliptical shape or a rectangular shape may be used.

  At one end 21a of the side port pressure vessel 21, a side port pressure vessel end cap 46 that forms a lid on the one end 21a side is a pressure vessel in which a fastening member n such as a bolt is fixed to the one end 21a. The end cap fixing jig 43 is fixed by being inserted and screwed. The pressure vessel end cap fixing jig 43 is fixed to one end portion 21 a of the side port pressure vessel 1.

The fixed porous plate 32 is fixed to the upstream side of the reverse osmosis membrane module 22 in the side port pressure vessel 21 by a fastening member (not shown), the movable porous plate 31, the connecting member 44, and the side port pressure vessel. The inner cap 26 disposed opposite to the end cap 46 is integrally fixed by a fastening member (not shown). The connection member 44 is formed with an opening 44a through which the supply water w1 flowing through the side port connection supply water pipe 21h (21h1, 21h2) passes.
A rotation handle 27 that is gripped when the user rotates the movable porous plate 31 is fixed to the inner cap 26.

  As a result, when the user grips the rotation handle 27 and rotates in the directions of arrows β1 and β2 in FIG. 13, one end of the side port pressure vessel 21 is obtained as in FIGS. 6A and 6B. The movable perforated plate 31 is rotated at an arbitrary angle with respect to the fixed perforated plate 32 fixed to the portion 21a to change the area (flow path) of the overlapping region of the hole 31a and the hole 31b, and the reverse of the supply water w1 The flow rate to the osmotic membrane module 22 can be adjusted.

  The movable porous plate 31, the connecting member 44, the fixed porous plate 32, the inner cap 26, the side port pressure vessel end cap 46, the pressure vessel end cap fixing jig 43, the water collection pipe end cap 23 c, and the fastening member materials And super stainless steel and glass fiber reinforced resin.

Next, the flow of the feed water w1 in the reverse osmosis unit U2 will be described.
In the configuration shown in FIG. 13, the supply water w <b> 1 flows into the side port pressure vessel 21 through the side port connection supply water pipe 21 h <b> 1, and a part of the holes 31 a of the movable porous plate 31 and the fixed porous plate 302. It passes through the flow path in the overlapping region of the hole 32a and flows into the reverse osmosis membrane module 22, and the rest passes from the side port pressure vessel 21 through the side port connecting supply water pipe 21h2 to the downstream side port pressure vessel 21. It flows out towards.

  As described above, with regard to the supply water w1 flowing into the reverse osmosis membrane module 22, the overlapping portion (region) of the hole 31a of the movable porous plate 31 and the hole 32a of the fixed porous plate 32 is a flow path of the supply water, The frictional resistance, expansion resistance, and reduction resistance due to this flow path become the fluid resistance of the feed water flowing into the reverse osmosis membrane module 22. Therefore, similarly to FIG. 6 described above, by rotating the movable porous plate 31 and changing the cross-sectional area of the flow channel, which is the overlapping region of the holes 31a of the movable porous plate 31 and the holes 32a of the fixed porous plate 32, The magnitude of the fluid resistance can be adjusted.

  At this time, since the movable perforated plate 31 is fixed to the inner cap 26 via the connecting member 44, the movable perforated plate 31 is rotated by rotating the inner cap 26 by applying external force to the rotation handle 27 gripped by the user. Can be rotated. As a result, the user can grasp the rotation handle 27 and adjust the rotation angle of the movable porous plate 31 from the outside of the side port pressure vessel 21 as indicated by arrows β1 and β2 in FIG. At this time, as described above, the rotation angle of the side port pressure vessel end cap 46 is marked and the pointer is provided on the rotation handle 27, so that the rotation of the movable porous plate 31 can be performed without using an angle measuring machine. The angle can be visually checked, and the installation process can be simplified.

According to the second embodiment, the water supplied to each side port pressure vessel 21 connected in parallel by the fluid resistance of the movable porous plate 31 and the fixed porous plate 32 of the resistor t inserted into the side port pressure vessel 21. Since the flow rate of w1 can be adjusted, there is no restriction caused by the flow rate distribution depending on the number of side port pressure vessels 21 connected in parallel.
Thereby, the amount of piping necessary for the water treatment plant (seawater desalination plant P) can be reduced, and the construction period can be shortened. The effect of rectification inside the end port pressure vessel 11 described in the first embodiment is also effective in the side port pressure vessel 21 of the second embodiment.

  Further, the porous body g1 in a modified form is applied to the second embodiment in the same manner as the first embodiment, so that the movable porous plate 31 and the fixed porous plate 32 at the one end portion 21a of the side port pressure vessel 21 or the other By applying to the upstream portion of the reverse osmosis membrane module 22, the same clogging suppression effect can be obtained in the second embodiment.

<< Modification 1 >>
FIG. 14 is a diagram showing the movable porous plate 41 and the fixed porous plate 42 according to the first modification. FIG. 14A shows the overlapping region of the holes 41 a of the movable porous plate 41 and the holes 42 a of the fixed porous plate 42. FIG. 14 (b) is a diagram in which a part of the overlapping region of the hole 41a of the movable porous plate 41 and the hole 42a of the fixed porous plate 42 is partially opened. is there.
In the first and second embodiments, the case where the holes 1a and 31a of the movable perforated plates 1 and 31 and the holes 2a and 32a of the fixed perforated plates 2 and 32 are made circular is illustrated, but in the first modification, the shape of the holes is changed. It is a long hole.

Specifically, the movable perforated plate 41 according to the first modification forms a long hole along the circumference around the rotation center 41o as a hole 41a, and the fixed perforated plate 42 includes the rotation center 41o of the movable perforated plate 41. A long hole along the circumference is formed as a hole 42a.
FIG. 14A shows a case where the hole 41a of the movable porous plate 41 and the hole 42a of the fixed porous plate 42 are completely overlapped to fully open the flow path r1 of the supply water w1.
FIG. 14B shows a case where the hole 41a of the movable porous plate 41 and the hole 42a of the fixed porous plate 42 are partially overlapped to make the flow path r1 of the supply water w1 part of the fully open state.

  According to the first modification, the hole 41a of the movable porous plate 41 and the hole 42a of the fixed porous plate 42 are elongated holes along the circumference around the rotation center 41o, so that the area of the flow path r1 can be easily obtained. Is possible. Therefore, since the flow path r1 can be increased or decreased in proportion to the rotation angle of the movable porous plate 41, the rotation operation of the movable porous plate 41 can be performed very easily.

<< Modification 2 >>
FIGS. 15 (a) and 15 (b) show that either one of the hole 51a of the movable porous plate 51 and the hole 52a of the fixed porous plate 52 is a long hole around the rotation center 51o, It is the figure which made the other the hole of shapes other than the said long hole, (a) shows a full open state, (b) shows a partially open state.

In the first modification, the case where the holes 41a of the movable porous plate 41 and the holes 42a of the fixed porous plate 42 are elongated holes around the rotation center 41o is exemplified. However, in the second modification, FIG. As shown, one of the hole 51a of the movable perforated plate 51 and the hole 52a of the fixed perforated plate 52 is a long hole along the circumference around the rotation center 51o, and the other is a region larger in the radial direction than the long hole. It is made into the hole which has.
FIG. 15 shows a case where the holes 51a of the movable perforated plate 51 are elongated holes around the circumference of the rotation center 51o, and the holes 52a of the fixed perforated plate 52 are fan-shaped holes 52a around the rotation center 51o. ing. The holes 52a of the fixed perforated plate 52 may have a shape other than the fan shape.

FIG. 15A shows a case where the overlapping region of the hole 51a of the movable porous plate 51 and the hole 52a of the fixed porous plate 52 is fully opened, and the flow path r2 is maximized.
FIG. 15B shows a case where a part of the overlapping region of the hole 51a of the movable porous plate 51 and the hole 52a of the fixed porous plate 52 is partially opened.
Also in the modified embodiment 2, the flow rate of the supply water w1 can be easily obtained by making the area of the flow path r2 into a long hole shape.

  As described above, according to the embodiments and modifications described above, the flow distribution adjustment function is provided inside the pressure vessel (end port pressure vessel 11, side port pressure vessel 21) into which the membrane module (reverse osmosis membrane module 12, 22) is inserted. Since the resistor t (movable perforated plate, fixed perforated plate) is inserted, the degree of freedom in piping layout can be ensured.

  Further, by individually adjusting the fluid resistance of the resistor t, the difference between the fluid resistance of the pipe and the fluid resistance of the membrane modules (reverse osmosis membrane modules 12, 22) is canceled, and the fluid resistance from the pump to each membrane module Can be made uniform. Furthermore, by adopting a structure in which the fluid resistance of the resistor t can be adjusted from the outside of the pressure vessel (end port pressure vessel 11 and side port pressure vessel 21), the membrane module (reverse osmosis membrane modules 12 and 22) accompanying a change with time is used. The fluid resistance of the resistor t is adjusted according to the change in fluid resistance, and the fluid resistance from the pump to each membrane module (reverse osmosis membrane modules 12, 22) can be made uniform.

Further, since it is not necessary to connect a valve to the pipe for the end port connection type reverse osmosis unit U1, it is possible to reduce the construction period and the maintenance and management cost of the pipe.
For the reverse osmosis unit U2 of the side port connection method, the number of side port pressure vessels 21 connected in parallel is not limited due to the flow distribution.
Thereby, the amount of piping necessary for the water treatment plant (seawater desalination plant P) can be reduced, and the construction period can be shortened.

<< Other Embodiments >>
In addition, although the case where the reverse osmosis membrane modules 12 and 22 were applied as a membrane module was illustrated in the said embodiment and modification, filtration membranes other than a reverse osmosis membrane may be sufficient.
Moreover, although the case where the fixed perforated plates 2, 32, 42, and 52 are separated from the end port pressure vessel 11 and the side port pressure vessel 21 is illustrated in the embodiment and the modified embodiment, they may be configured integrally.

In addition, although the case where the movable perforated plates 1, 31, 41, and 51 are moved by a rotational motion has been exemplified in the above-described embodiment and modifications, they may be moved by a linear motion. In this case, the movable perforated plate may be configured as a single unit or divided into arbitrary plural pieces. Also in this case, it is desirable that the flow path of the supply water w1 be pointed with respect to the center of the cross section in the pressure vessel so that the supply water w1 is uniformly supplied to the membrane module.
In the above-described embodiments and modifications, various configurations have been described, but the configurations may be appropriately combined.

  While various embodiments and variations of the present invention have been described above, the description is intended to be exemplary. Accordingly, various modifications and changes can be made within the scope of the present invention. That is, the present invention can be arbitrarily changed as appropriate without departing from the spirit of the invention.

1, 31, 41, 51 Movable porous plate (resistor, movable plate)
1a, 31a, 41a, 51a hole (second hole, long hole)
2, 32, 42, 52 Fixed perforated plate (resistor, fixed plate)
2a, 32a, 42a, 5a2 holes (first hole, long hole)
7, 27 Rotating handle (operating member)
11 End port pressure vessel (pressure vessel)
12, 22 Reverse osmosis membrane module (membrane module)
14 Permeated water piping (piping)
15 Header pipe for water supply (pipe)
17 Concentrated water header pipe (pipe)
21 Side port pressure vessel (pressure vessel)
21h Piping for supply water for side port connection (piping)
24 Permeated water piping (piping)
28b Concentrated water piping for side port connection (piping)
bi Organic matter and microorganisms (contaminants)
g1 porous body t resistor U1, U2 Reverse osmosis unit (water treatment system)
w1 Supply water (water, untreated water)

Claims (4)

A membrane module that performs water filtration, a pressure vessel in which the membrane module is inserted, and a water treatment system in which a plurality of the pressure vessels are connected in parallel via a pipe,
A plate shape that moves along the direction perpendicular to the flow direction of the untreated water supplied to the upstream of the membrane module in the pressure vessel to give variable resistance to the untreated water and increase or decrease its flow rate. A water treatment system comprising a resistor. The water treatment system according to claim 1,
The resistor is a fixed plate having a first hole and a movable plate having a second hole,
The fixing plate is provided integrally with the pressure vessel,
The movable plate is connected to an operation member located at an end of the pressure vessel and is provided close to the fixed plate;
The water treatment system, wherein the movable plate is rotated by rotating the operation member, the size of the overlapping region of the first hole and the second hole is changed, and the flow rate is increased or decreased. The water treatment system according to claim 2,
At least one of the first hole and the second hole is a long hole along a circumference around the rotation center of the movable plate. The water treatment system according to claim 2 or claim 3,
A water treatment system comprising a porous body having a hole through which untreated water to be supplied passes and removes contaminants upstream of the membrane module in the pressure vessel.

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