JPH11207340A - Replenishing device of condensed water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently perform a membrane separation treatment of replenishing water with a spiral type membrane module. SOLUTION: This patent refers to a replenishing device of condensed water for treating the replenishing water with the spiral type membrane module, and the spiral type membrane module consists of a wound body formed by winding a bag shaped separation membrane 10 around a shaft 20, and feeds the raw water from one end face of the wound body and takes out transmitted water and concentrated water from the other end face of the wound body. Thus, the replenishing water can be very efficiently subjected to the membrane treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying make-up water to condensate water, and more particularly to an apparatus for replenishing condensate water, which is configured to treat raw water by a spiral type membrane module and replenish it.

[0002]

2. Description of the Related Art In a thermal power plant or a nuclear power plant, pure water is heated to generate steam, thereby driving a turbine and operating a generator. Usually, since steam is supplied to the outside of the circulating system of the condenser, the boiler, and the condenser, pure water is supplied to the circulating system from outside the system.

FIG. 6 is a system diagram showing a conventional make-up water purification system and a condensate circulation system. The condensate in the condenser 62 returned from the turbine 61 is formed of iron mixed in the condensate in the circulation system. After the clad (a mixture of iron oxide particles) is removed by the hollow fiber membrane filter 63, the mixture is subjected to an ion exchange treatment by a mixed bed type ion exchange device 64. And the low pressure heater 65 and the deaerator 6
6. Steam generated via the high-pressure heater 67 and the boiler 68 is supplied to the turbine 61, and the condensate is circulated to the condenser 62.

[0004] Makeup water (pure water) supplied to the condenser 62
The raw water such as industrial water or city water is processed by a pretreatment device 70 and a pure water device 71 via a raw water tank 69, and a pure water tank 72
And supplied via a makeup water tank 73. Pretreatment device 7
Numeral 0 is a flocculation / pressurized flotation filtration device when the raw water is industrial water, and a high-speed filtration device using a long fiber bundle when the raw water is city water. Further, the pure water apparatus 71 is constituted by a four-bed five-column ion exchanger, or a four-bed five-column ion exchanger and a mixed-bed ion exchanger.

In the condensing water circulation system, the condensed water circulation amount may fluctuate due to fluctuations in the amount of power generation, and the lower water level of the water condenser 62 may rise. A pipe for returning to the tank 73 is provided.

In such a conventional make-up water purification system and condensate circulating system, the following contaminants flow into the condensate circulating system.
The differential pressure of No. 3 easily rises and the frequency of backwashing is high. The increase in the differential pressure is more likely to occur as the water flow rate is set higher. Fine particles derived from raw water that could not be removed by the pretreatment device Microorganisms generated in the pure water device or tank Fine particles mixed into the tank from the atmosphere (Since the pure water tank and makeup water tank are not completely sealed, There is a possibility that fine particles may be mixed in.) Iron clad generated in the condensate circulation system, mixed into the surplus water and flowed into the makeup water tank JP-A-6-134490 discloses pure water in the makeup water purification system. It has been proposed to provide a cross-flow type membrane filtration device in the device, and if such a device is provided with a membrane filtration device, it is possible to prevent the above-mentioned contaminants derived from raw water from flowing into the condensate circulation system. Can be. The publication does not disclose the type of the membrane module.

Japanese Unexamined Patent Publication No. 9-239362 discloses an apparatus for supplying replenishing water to a condenser by supplying replenishing water obtained by purifying raw water by a purifying means to a condenser. And feeds permeated water of the membrane filtration device directly to a condenser. In the makeup water supply device of the same publication, the membrane filtration device mixes into the makeup water from the condensate circulation system into the surplus water, as well as the fine particles derived from the raw water and the microorganisms and the fine particles mixed in the purification system. To remove the iron cladding
Since the obtained permeated water is directly supplied to the condenser, it is possible to reliably prevent these contaminants from flowing into the condensate circulation system.

The present invention, in a replenishing device for purifying replenishing water by such a spiral type membrane filtration device, uses a spiral membrane module which is significantly improved as compared with the conventional type. Next, the configuration of the spiral type membrane module will be described with reference to the drawings.

FIG. 5 is a partially exploded perspective view showing the structure of a conventional spiral membrane module. A plurality of bag-shaped separation membranes 2 are wound around a water collecting pipe 1 via a mesh spacer 3.

The water collecting pipe 1 is provided with a slit-like opening communicating between the inside and the outside of the pipe. The separation membrane 2 has a bag shape,
The central part surrounds the water collection pipe 1. A channel material 4 made of a mesh spacer or the like is inserted inside the bag-shaped separation membrane 2, and the inside of the bag-shaped separation membrane (bag-shaped membrane) 2 is a permeated water channel.

A top ring 6 and an end ring 7 are provided at both ends of the wound body 5 of the bag-like membrane 2, and a brine seal 8 is provided around the outer periphery thereof.

The raw water flows into the raw water flow path between the bag-like membranes 2 from the front end face of the wound body 5, flows as it is in the longitudinal direction of the wound body 5, and concentrates from the rear end face of the wound body 5. Leaked as. While flowing through the raw water flow path, water permeates the bag-like membrane 2 and enters the inside thereof, flows into the water collecting pipe 1, and is taken out of the module from the rear end side of the water collecting pipe 1.

[0013]

The conventional spiral type membrane module shown in FIG. 5 has the following problems to be solved.

In order to increase the flow rate of the permeated water in the water collecting pipe 1, it is necessary to increase the diameter of the water collecting pipe 1, but in such a case, the diameter of the spiral membrane module also becomes large. The permeated water that has permeated into the bag-shaped membrane 2 flows to the water collecting pipe 1 while spirally flowing through the bag-shaped membrane 2.
The flow resistance in the bag-like membrane 2 is large. Moreover, the flow resistance near the slit portion of the water collecting pipe flowing into the water collecting pipe 1 from the inside of the bag-shaped membrane 2 is large. The flow rate of the raw water flowing through the raw water flow path decreases toward the downstream side. (The flow rate of raw water decreases as much as the raw water is concentrated.)
For this reason, the raw water flow velocity is low in the downstream of the raw water flow path,
Dirt easily adheres.

The present invention solves the above-mentioned conventional problems, and provides a condensate replenishing device which can efficiently treat replenishing water by a spiral type membrane module which does not require a water collecting pipe and has low permeated water flow resistance. The purpose is to provide.

[0016]

SUMMARY OF THE INVENTION A condensate replenishing apparatus according to the present invention is a condensate replenishing apparatus for supplying raw water as make-up water by treating raw water with a spiral membrane module. Is characterized in that the membrane is wound around a shaft to form a roll, raw water is supplied from one end face of the roll, and permeated water is taken out from the other end face of the roll. .

The spiral membrane module employed in the present invention is a spiral membrane module in which a permeated water flow path material is disposed inside a bag-like membrane, and a raw water flow path material is disposed between the bag-like membranes. The bag-like membrane is substantially rectangular with first, second, third and fourth sides, and the first, second and third sides are sealed and the fourth A part of the side part is an open part and the remaining part is a closed part, and a first side part orthogonal to the fourth side part is applied to a shaft to wind a bag-like membrane to form a wound body, The fourth side faces the rear end face of the wound body, the second side facing the fourth side faces the front end face of the wound body, between the bag-shaped films. The raw water flow path of the third
The entire side of the bag-shaped membrane is sealed, and in the fourth side, a portion overlapping with the open portion of the bag-shaped film is a closed portion, and a portion overlapping with the closed portion of the bag-shaped film is open. It is preferably a part.

In this spiral type membrane module, raw water flows into the raw water flow path from the front end face of the wound body. The raw water flows through the raw water flow path in a direction substantially parallel to the axis of the wound body, and then flows out as concentrated water from the raw water flow path opening at the rear end face of the wound body.

The water that has passed through the bag-like membrane flows in the bag-like membrane in a direction substantially parallel to the axis of the wound body, and flows out of the bag-shaped membrane opening at the rear end face of the wound body.

As described above, since the permeated water flows in the bag-shaped membrane in a direction parallel to the axis of the wound body, the water collecting pipe used in the conventional spiral membrane module becomes unnecessary. Then, there is no flow resistance when flowing into the water collecting pipe from inside the bag-shaped membrane, and the flow resistance of permeated water is reduced.

Since the water collecting pipe is eliminated, the length of the bag-like membrane in the winding direction can be increased by that much.
The membrane area can be expanded. And even if the length in the winding direction of the bag-like membrane is increased, the flow resistance of the permeated water does not increase,
The amount of permeated water can be increased.

Further, since the raw water flow path is opened only at a part of the rear end face of the wound body, the flow rate of the raw water (concentrated water) at the downstream side of the raw water flow path can be increased more than before. In addition, the adhesion of dirt in the downstream area of the raw water flow path can be prevented.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 7 is a system diagram showing an embodiment of the condensate replenishing device of the present invention. 7, members having the same functions as the members shown in FIG. 6 are denoted by the same reference numerals.

The condensate replenishing device of the present invention shown in FIG.
Membrane filtration device 74 having spiral membrane module 4
6 and supplies permeated water to a condenser 62, which is different from the conventional apparatus of FIG.

The concentrated water of the membrane filtration device 74 is preferably returned to the raw water tank 69 as shown in FIG. 7 to increase the water recovery rate. Note that the concentrated water may be used as cooling water or the like in the power plant equipment.

The membrane of the membrane filtration device used in the present invention includes:
MF (microfiltration) membranes, UF (ultrafiltration) membranes or RO (reverse osmosis) membranes are preferred, and from the viewpoint of energy efficiency, MF membranes or UF membranes are preferred.

Hereinafter, a spiral type membrane module used in the embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a perspective view of a bag-like membrane of the spiral membrane module and a shaft around which the bag-like membrane is wound. FIGS. 1B and 1C respectively show B in FIG. 1A.
It is sectional drawing which follows the -B line and CC line. FIG. 2 is a sectional view showing a method of winding a bag-like membrane around a shaft, FIG. 3 is a perspective view showing an engagement relationship between a wound body and a socket, and FIG. 4 is a side view of a spiral membrane module.

As shown in FIG. 1, the bag-like film 10 has a square or rectangular shape, and has a first side portion 11 and a second side portion 11.
, A third side 13, and a fourth side 14. In the first side 11, the second side 12, and the third side 13, the separation membrane films are bonded to each other with an adhesive or the like, and only a part of the fourth side 14 is bonded. In addition, as the bag-like film 10, one long film is folded in two at the second side 12, and one of the first side 11, the third side 13, and the fourth side 14 is formed. The parts may be bonded.

From the middle of the fourth side 14 to the third side 13
The separation membrane films of the bag-like membrane 10 are not adhered to each other, and the opening portion 30 for permeated water outflow is formed. Further, from the middle of the fourth side portion 14 to the first side portion 11, the separation membrane films of the bag-like membrane 10 are adhered to each other, forming a closing portion 31 for preventing outflow of permeated water. I have.

A permeated water channel material (for example, made of a mesh spacer) 15 is inserted into the bag-like membrane 10.

On one surface of the bag-like film 10, an adhesive 1
6 is adhered and adhesives 17 and 18 are adhered to the other surface, and the bag-like film 10 is wound around the shaft 20. The adhesive 16 is applied along the first side 11, and the adhesive 17 is applied along the third side 13. The adhesive 18 is applied along the opening 30 for outflow of permeated water from the intermediate portion in the longitudinal direction of the fourth side portion 14 to the third side portion 13.

By winding a plurality of bag-like films 10 around the shaft 20, the overlapped bag-like films 10 are joined in a water-tight manner at the adhesives 17 and 18. Thus, a raw water flow path through which raw water (and concentrated water) flows is formed between the bag-shaped membranes 10. As the adhesive 18 cures, an open portion for flowing out the raw water (concentrated water) is formed on the rear end surface of the wound body on the inner peripheral side, and a closing portion for preventing raw water outflow is formed on the outer peripheral side. You.

Fins 19 extend from the boundary between the open portion 30 for permeated water outflow and the closed portion 31 for permeate outflow prevention in the fourth side portion 14 toward the rear of the wound body. I have. The fins 19 are made of, for example, a synthetic resin film or sheet, and are preferably bonded to the bag-like film 10 by adhesion or the like.

By winding the bag-like membrane 10 around the shaft 20 via a raw water flow path material (mesh spacer) 29 as shown in FIG. 2, a wound body 24 is formed as shown in FIG. The fin 19 extends from the rear end face of the wound body 24. By providing the fins 19 at the same location on the fourth side portion 14 of each bag-like film 10, the fins 19
Are located equiradially from the axis of the winding body 24 and
The fins 19 form a ring-shaped protrusion by overlapping the 9. The rear end of the cylindrical socket 25 is inserted into the ring-shaped protrusion, and the socket 25 and the fin 19 are joined with an adhesive or the like. Note that the socket 25 may be externally fitted to the fin 19. Also, fin 1
A cutting groove may be formed on the rear end face of the wound body 24 along the line 9 by a lathe, and the end of the socket 25 may be embedded in the groove.

By joining the socket 25 and the fin 19 in this manner, a permeated water outflow area on the outer peripheral side of the rear end face of the wound body 24 and a concentrated water outflow area on the inner peripheral side of the socket 25 are defined. .

When the bag-like film 10 is wound around the shaft 20, as shown in FIG.
A raw water flow path material (mesh spacer) 29 is interposed between them. The raw water flow path is formed by interposing these mesh spacers 29.

As shown in FIG. 4, a top ring 26 and an end ring 27
Is formed by a synthetic resin mold or the like, and the top ring 26 is formed.
A brine seal 28 is provided around the outer periphery of.

The condensate replenishing device of the present invention, as described above,
FIG. 7 shows a spiral-type membrane module configured as described above.
And replenishment water is treated by incorporating it into a membrane filtration device 74. As shown in FIG. 4, the makeup water flows from the front end face of the wound body 24 into the raw water flow path between the bag-like membranes 10 as raw water. This raw water flows through the raw water flow path in a direction substantially parallel to the axis of the wound body 24, and the socket 25 at the rear end of the wound body 24
Taken out from the inner end face. Then, while the raw water flows through the raw water flow path, the water permeates into the bag-like membrane 10, and the permeated water flows out from the outer peripheral side of the socket 25 on the rear end surface of the wound body 24.

In this spiral membrane module, the permeated water flows in the bag-like membrane 10 in a direction parallel to the axis of the wound body 24 and is taken out from the rear end face. The used collecting pipe is unnecessary. For this reason, the flow resistance when flowing from the bag-like membrane into the water collecting pipe is eliminated, and the permeated water flow resistance is significantly reduced.

The water collecting pipe is omitted, and the length of the bag-like membrane 10 in the winding direction can be increased accordingly.
It is possible to increase the film area. Even if the length of the bag-like membrane in the winding direction is increased, the permeated water flow resistance does not increase,
The amount of permeated water can be increased.

In this spiral type membrane module, the outlet of the raw water flow path is provided only inside the socket 25, and the outlet (the most downstream part) of the raw water flow path is narrowed. The flow rate of the raw water (concentrated water) becomes sufficiently large also on the downstream side of the road, and the adhesion of dirt in the downstream area of the raw water flow path can be prevented. The area inside and outside the socket 25 (the length of the adhesive 18 in the side portion 14 direction) is preferably determined according to the water recovery rate of the spiral membrane module.

In the above embodiment, the socket 25
A permeated water outflow portion is arranged on the outer peripheral side of the socket 25, and a concentrated water outflow portion is arranged inside the socket 25. Conversely, the inside of the socket 25 is used as the permeated water outflow portion, and the outer peripheral side of the socket 25 is concentrated water outflow. It may be configured to be a part.

[0043]

EXAMPLES Examples and comparative examples will be described below.

[Example 1] Water was subjected to coagulation filtration treatment in a pretreatment device 70, and then treated in a pure water device 71 comprising a four-bed, five-column ion exchange device and a mixed-bed ion exchange device. In the actual makeup water supply device of the flow shown in FIG. 7 which supplies the water to the condenser through the tank 72, the makeup water tank 73, and the membrane filtration device 74, a spiral membrane having a configuration shown in FIGS. The module was incorporated into a membrane filtration device 74.

The membrane area of this membrane module is 0.87 m ²
And the diameter is 10 cm and the length is 40 cm.

The solid content (such as iron clad) of the makeup water flowing into the membrane filtration device 74 was 3 μg / L. When this water was passed through the membrane filtration device 74 at 22 m ³ / m ² / day, the permeated water flux was 20 m ³ / m ² / day on average.

[Comparative Example 1] As a membrane module of the membrane filtration device 74, a spiral type membrane module having the structure shown in FIG.
cm) except that the same make-up water was treated in the same manner as in Example 1, and the average permeate flux was 3 m ³ / m ^2.
/ Day was much lower than that of Example 1.

[0048]

As described above, the condensate replenishing apparatus according to the present invention can perform the membrane separation of the replenished water extremely efficiently.

[Brief description of the drawings]

FIG. 1A is a perspective view of a bag-shaped membrane of a spiral membrane module used in a condensate replenishing apparatus according to an embodiment, and FIG. 1B is a view taken along the line BB in FIG. Sectional view,
FIG. 3C is a cross-sectional view taken along line CC in FIG.

FIG. 2 is a cross-sectional view showing a method of winding a bag-like membrane of the spiral membrane module of FIG.

FIG. 3 is a perspective view showing an engagement relationship between a wound body and a socket of the membrane module of FIG. 1;

FIG. 4 is a side view of the spiral membrane module of FIG. 1;

FIG. 5 is a partially exploded perspective view showing the structure of a conventional spiral membrane module.

FIG. 6 is a system diagram showing a conventional makeup water purification system and a condensate circulation system.

FIG. 7 is a system diagram showing one embodiment of a device for supplying make-up water to a condenser according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 bag-like membrane 11 first side 12 second side 13 third side 14 fourth side 15 flow path material 16, 17, 18 adhesive 19 fin 20 shaft 24 wound body 25 socket 29 Mesh spacer 30 Open part for permeated water outflow 31 Closed part for permeated water outflow prevention 61 Turbine 62 Condenser 63 Hollow fiber membrane filter 64 Mixed bed type ion exchanger 65 Low pressure heater 66 Deaerator 67 High pressure heater 68 Boiler 69 Raw water tank 70 Pretreatment device 71 Pure water device 72 Pure water tank 73 Make-up water tank 74 Membrane filtration device

Claims (2)

[Claims] 1. A condensate replenishing device for supplying raw water as replenishment water by treating raw water with a spiral type membrane module, wherein the spiral type membrane module has a membrane wound around a shaft to form a wound body, Raw water is supplied from one end surface of the wound body,
A condensate replenishing device wherein permeated water is taken out from the other end surface of the wound body. 2. The bag according to claim 1, wherein the membrane is a bag-like membrane in which a permeated water channel material is disposed, and the bag-like membrane is a first membrane.
It is a substantially rectangular shape having second, third and fourth sides, the first, second and third sides are sealed, the fourth side is partially open, and the remainder is The spiral-type membrane module is a closed part, and the first side part orthogonal to the fourth side part is applied to a shaft to wind a bag-like membrane into a roll, and the fourth side is formed. Part facing the rear end face of the wound body, a second side part facing the fourth side part facing the front end face of the wound body, and a raw water flow path between the bag-shaped membranes. The third side portion is entirely sealed, and in the fourth side portion, a portion overlapping with the open portion of the bag-shaped film is a closed portion, and the closed portion of the bag-shaped film is closed. A condensate replenishing device, characterized in that it is a spiral-wound membrane module in which the portion overlapping with the spiral membrane module is an open part.