JPH10272466A - Condensate filtration device - Google Patents

Abstract

(57) [Summary] (Problems corrected) [PROBLEMS] The inflow nozzle 6 and the drain nozzle 15 are separately provided on the lower end plate 1A that requires skill and is difficult to perform annealing treatment, so that the manufacturing cost of the sealed container 1 increases. Therefore, the present invention provides a condensate filtration device in which the inflow nozzle and the drain nozzle are integrated and provided at the center of the bottom of the closed vessel. SOLUTION: A condensate filtration device includes a lower chamber 2 in an airtight container 1.
And a partition plate 4 for partitioning the upper chamber 3, a hollow fiber membrane module 5 having an upper end fixed to the partition plate 4 and a lower end hanging down to the lower chamber 2, and condensate to be filtered by the hollow fiber membrane module 5. In the condensate filtration device including the inflow nozzle 6 attached to the lower end plate 1A of the closed container 1 into which the inflow flows, and the drain nozzle 15 provided adjacent to the inflow nozzle 6,
The inflow nozzle 6 having an integrated drain nozzle is provided at the center of the lower end plate 1A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condensate filtration device suitably used for, for example, a nuclear power plant or a thermal power plant, and more particularly to a condensate filtration device using a hollow fiber membrane as a filter medium.

[0002]

2. Description of the Related Art As shown in FIG. 3, for example, a conventional condensate filtration device of this type comprises a closed vessel 1 and a partition plate 4 which is divided into a lower chamber 2 and an upper chamber 3 at the top of the closed vessel 1. A plurality of hollow fiber membrane modules 5 hanging down from the partition plate 4 to the lower chamber 2, for example, by filtering condensed water from a nuclear power plant or a thermal power plant to remove insoluble suspended substances such as iron oxide. Configured to remove. Each hollow fiber membrane module 5 is arranged so as to form a predetermined geometric pattern such as a honeycomb shape with respect to the partition plate 4. The bottom 1A and the top 1B of the closed container 1 are both formed by end plates. Therefore, the bottom 1A is hereinafter referred to as the lower head 1A, and the top 1A.
B is referred to as an upper head plate 1B. An inflow nozzle 6 through which condensate flows in is mounted at a position offset from the center of the lower head plate 1A, and an outflow nozzle 7 through which filtered water flows out is mounted at the center of the upper head plate 1B. An inflow pipe 6A is connected to the inflow nozzle 6, an outflow pipe 7A is connected to the outflow nozzle 7, and valves 6B and 7B are attached to the respective pipes 6A and 7A.

A baffle plate 9 facing the inflow nozzle 6 is provided in the lower chamber 2, and condensed water flowing from the inflow nozzle 6 is dispersed by the baffle plate 9 into the lower chamber 2. Further, a baffle plate 10 facing the outflow nozzle 7 is provided in the upper chamber 3, and the filtered water in the upper chamber 3 is collected by the baffle plate 10 and discharged from the outflow nozzle 7. Between the baffle plate 9 and the lower end of the hollow fiber membrane module 5, a distribution mechanism 11 for further dividing the lower chamber 2 up and down is provided.
Thus, the condensed water dispersed by the baffle plate 9 is once blocked and subsequently distributed to each hollow fiber membrane module 5. That is, the distribution mechanism 11 includes a plate 11A that divides the lower chamber 2 into a space on the hollow fiber membrane module 5 side and a space below the plate 11A, and a distribution pipe attached to the plate 11A corresponding to each hollow fiber membrane module 5. 11B, and air is distributed at the time of backwashing by each distribution pipe 11B.

[0004] The closed vessel 1 is connected to an air pipe for scrubbing suspended substances such as iron oxide fine particles adhered to many hollow fiber membranes constituting the hollow fiber membrane module 5 and for air surge. I have. The air pipe includes an air inflow pipe 12 branching from the outflow pipe 7A, an air inflow pipe 13 connected slightly below the distribution mechanism 11 of the lower chamber 2, and a lower chamber 2
And an air vent pipe 14 connected to the upper part of the air outlet.
Each pipe 12, 13, 14 has a valve 12A, 1
3A and 14A are attached respectively. In addition, a drain nozzle 15 is attached to the center of the lower end plate 1A, and a drain pipe 15A connected to the nozzle 15 is provided.
The valve 15B is opened to drain the washing wastewater containing the suspended matter.

Next, the operation of the condensate filtration device will be described. When filtering the condensate, the valves 6B and 7B of the inflow pipe 6A and the outflow pipe 7A are opened, and the other valves are closed. When condensed water is supplied in this state, the condensed water flows into the lower chamber 2 from the inflow pipe 6A and collides with the baffle plate 9, where the condensed water is dispersed. The condensed water after the dispersion mainly flows into the hollow fiber membrane module 5 from the distribution pipe 11B of the distribution mechanism 11. This condensate is applied to each hollow fiber membrane module 5
During the permeation from the outside to the inside of each hollow fiber membrane, suspended substances such as iron oxide fine particles in the condensate are captured on the membrane surface of the hollow fiber membrane. The filtered water is obtained inside each hollow fiber membrane, and the filtered water rises in each hollow fiber membrane and flows out of the upper end opening of each hollow fiber membrane into the upper chamber 3, and further, the baffle plate 10 and the outflow nozzle For example, the water is supplied to the condensate and desalination unit in the subsequent process through the outlet 7 and the outlet pipe 7A. If the filtration treatment is continued, suspended matter accumulates on the hollow fiber membrane, and the differential pressure of the filtration device becomes equal to or higher than a specified value, thereby hindering the subsequent filtration treatment. Therefore, at this point, the filtration process is stopped and the following washing operation is performed.

[0006] The cleaning operation is performed by supplying compressed air into the lower chamber 2 and scrubbing with bubbles generated in the lower chamber 2. That is, the valves 6B and 7B of the inflow pipe 6A and the outflow pipe 7A are closed, and the valves 1 of the air inflow pipe 13 and the air release pipe 14 are kept in a state where the lower chamber 2 and the upper chamber 3 are full.
3A and 14A are opened, and compressed air is supplied from the air inlet pipe 13 into the lower chamber 2. The air that has flowed into the lower chamber 2 is temporarily blocked by the distribution mechanism 11,
B flows into the corresponding hollow fiber membrane module 5 as bubbles. In each hollow fiber membrane module 5, water is agitated when bubbles rise, and by this agitation action, each hollow fiber membrane 51 is stirred.
Vibrates, and the captured suspended matter is separated from each hollow fiber membrane. The exfoliated suspended matter flows out to the outside along with water and bubbles in each hollow fiber membrane module 5 and is deposited in the lower chamber 2.
On the other hand, the air bubbles flowing out of each hollow fiber membrane module 5 flow out of the filtration device through the air vent tube 14.

Further, after performing the above-described scrubbing operation, the valve 13A of the air inlet pipe 13 is closed while the valve 14A of the air vent pipe 14 is kept open, and the valve 15B of the drain vent pipe 15A is opened. The cleaning wastewater in the chamber 2 flows out of the drain pipe 15A to the outside due to a head difference. Thereby, the filtration function of each hollow fiber membrane module 5 can be restored. At this time, if compressed air is supplied from the air inlet pipe 13 and / or the air vent pipe 14,
The air pressure promotes the outflow of washing wastewater.

After the scrubbing operation, valves 12A and 15B of air inlet pipe 12 and drain pipe 15A are provided.
With each open and the other valves closed.
When compressed air is supplied from the air inlet pipe 12, the compressed air flows into the upper chamber 3, and the filtered water remaining in the upper chamber 3 flows back into each hollow fiber membrane 51 due to the air pressure, and each hollow fiber membrane 51
From the inside to the outside, whereby the suspended substance clogging the micropores of each hollow fiber membrane 51 is washed out, an air surge is performed, and the hollow fiber membrane 51 can be extracted from the drain pipe 15A together with the washing wastewater.

Incidentally, among the condensate filtration devices, there is a precoat type filtration device in addition to the above-mentioned hollow fiber membrane filtration device.
In the case of a precoat type filtration device, a large amount of a precoat agent containing suspended substances is peeled off by a backwashing operation. And this precoat agent is discarded. Therefore, when a precoat filtration device is used in a nuclear power plant such as a boiling water nuclear power plant, for example, suspended substances such as iron oxide fine particles are radiated and cannot be directly disposed of. In addition, the amount of the pre-coating agent is large for the separated suspended substance, and the amount of radiation waste to be stored increases accordingly. Therefore, in a nuclear power plant, a hollow fiber membrane filtration device that does not usually use a precoat agent is widely used.

[0010]

However, in the case of a condensate filtration device using a conventional hollow fiber membrane, the inflow nozzle 6 and the drain nozzle 15 are individually attached to the lower end plate 1A, which is difficult to perform an annealing process and requires skill. Because it is provided, closed container 1
However, there was a problem that the manufacturing cost was high. Moreover,
In order to reliably discharge the washing waste liquid from the inside of the closed vessel 1 to the outside, the drain nozzle 15 is disposed at the center of the lower head 1A, and the inflow nozzle 6 is arranged so as to be deviated from the center of the lower head 1A. Is displaced from the center of the lower end plate 1A, so that the condensed water is hardly evenly dispersed by the baffle plate 9 over the entire lower space of the dispersing mechanism 11, and condensed water rises from the distribution pipe 11B to the hollow fiber membrane module 5 side. The flow rate of the hollow fiber membrane module tends to be lost, and there is some difficulty in performing the uniform filtration treatment by each hollow fiber membrane module 5.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to reduce the manufacturing cost of a sealed container and to maintain the filtration performance of each hollow fiber membrane module uniformly throughout. It is intended to provide a water filtration device.

[0012]

A condensate filtration device according to the present invention has a partition plate for partitioning the inside of a closed vessel into a lower chamber and an upper chamber, an upper end fixed to the partition plate, and a lower end hanging down to the lower chamber. A condensate filtration device comprising a hollow fiber membrane module and an inflow nozzle into which condensate flows into the bottom of the hermetic container, and a drainage nozzle attached to the bottom of the hermetic container adjacent to the inflow nozzle. The inflow nozzle integrated with the drain nozzle is provided at the center of the bottom of the closed container.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, based on the embodiments shown in FIG. 1 and FIG. In each of the drawings, FIG. 1 is a cross-sectional view showing one embodiment of the condensate filtration device of the present invention, and FIG. 2 is a cross-sectional view showing a hollow fiber membrane module used in the condensate filtration device of the present invention.

As shown in FIG. 1, the condensate filtration device according to the present embodiment includes a closed container 1, a partition plate 4 for partitioning the inside of the closed container 1 into a lower chamber 2 and an upper chamber 3, And a plurality of hollow fiber membrane modules 5 whose upper end is fixed and whose lower end hangs down to the lower chamber 2 side. A large-diameter inflow nozzle 6 is attached to the center of the lower end plate 1A, and the inflow nozzle 6 is connected to an inflow pipe 6A. This inflow pipe 6
A is connected to a small-diameter drain pipe 15A arranged downstream of the valve 6B. That is, in the present embodiment, the drain nozzle is integrated with the inflow nozzle 6, and also serves as an inlet for the condensate and an outlet for the washing waste liquid. The baffle plate 9 is opposed to the inflow nozzle 6 so that the lower end plate 1
A is fixed to the inner surface.

The partition plate 4 also serves as a fixing plate for fixing the upper end of the hollow fiber membrane module 5. The lower end of the hollow fiber membrane module 5 is supported by a support plate 18 disposed slightly above the distribution mechanism 11. Holes corresponding to the hollow fiber membrane modules 5 hanging from the partition plate 4 are formed in the support plate 18, and the lower end of each hollow fiber membrane module 5 is inserted into each hole. The partition plate 4 and the support plate 18 are connected by a plurality of connecting rods 19. Although the description is omitted, the hollow fiber membrane module 5 is fixed by the partition plate 4, the support plate 18, and the like in the conventional condensate filtration device.

Therefore, when mounting the hollow fiber membrane module 5 in the closed container 1, for example, the upper ends of all the hollow fiber membrane modules 5 are fixed to the partition plate 4, and the lower ends of the hollow fiber membrane modules 5 hanging down from the partition plate 4 Is fixed in the hole of the support plate 18 and the connecting rod 19 is bolted to the support plate 18 to integrate these three members. The partition plate 4 and the hollow fiber membrane module 5 integrated as described above are mounted in the closed container 1 using a crane. In this state, a slight gap is formed between the lower end of the hollow fiber membrane module 5 and the distribution mechanism 11.

The hollow fiber membrane module 5 is configured, for example, as shown in FIG. That is, as shown in FIG.
The front and rear hollow fiber membranes 51 are provided, and a protective tube 52 that bundles and stores the hollow fiber membranes 51 is provided. Each hollow fiber membrane 51 has an outer diameter of 0.3 to 7 mm and an inner diameter of 0.2 to 5 by a resin thin film having fine pores of 0.01 to 0.3 μm, for example.
mm of hollow fiber. In addition, the protection cylinder 52
A flange portion 52A is formed at the upper end portion of the partition plate 4, and the flange portion 52A hangs on the partition plate 4 at the flange portion 52A. The hollow fiber membrane module 5 is fastened and fixed to the partition plate 4 by bolts or the like at the flange portion 52A. A skirt portion 52B is formed at a lower end portion of the protection cylinder 52, and the skirt portion 52B collects air flowing from the distribution pipe 11B of the distribution mechanism 11 at the time of cleaning. An upper joint 53 is formed by binding the upper ends of the hollow fiber membranes 51 with an adhesive or the like at the upper end of the protective cylinder 52, and joining the lower ends of the hollow fiber membranes 51 with the upper end at the lower end. A lower joining portion 54 joined and fixed in the same manner as described above is formed. At the upper joint 53, each hollow fiber membrane 51 is open, and at the lower joint 54, each hollow fiber membrane 51 is closed, so that filtered water flows out of the opening of the hollow fiber membrane 51 and collects in the upper chamber 3. It is. When collecting water from both ends of each hollow fiber membrane 51, the lower end of each hollow fiber membrane 51 is also opened like the upper end. Also,
In the case of the present embodiment, a flow hole 54A is formed in the lower joint portion 54, and the air bubbles collected in the skirt portion 52B flow into the hollow fiber membrane module 5 through the flow hole 54A.

Further, flow holes 52C and 52D are formed slightly below the upper joint 53 and slightly above the lower joint 54 of the protective cylinder 52, respectively.
The condensate flows into the hollow fiber membrane module 5 via C, 52D and the flow hole 54A.

Next, the operation will be described. When filtering the condensate, the valves 6 of the inflow pipe 6A and the outflow pipe 7A are used.
B and 7B are respectively opened, and the other valves are closed. When condensed water is supplied in this state, the condensed water flows in from the inflow nozzle 6 and flows in the baffle plate 9 while being uniformly dispersed throughout the lower space of the distribution mechanism 11. Next, most of the condensate rises from the distribution pipe 11B of the distribution mechanism 11 to the hollow fiber membrane module 5 side at a substantially uniform flow rate, and the protection cylinder 52
Flow holes 52C and 52D and flow hole 5 of lower joint portion 54
It flows into the hollow fiber membrane module 5 through 4A. In each hollow fiber membrane module 5, the condensate is condensed in each hollow fiber membrane 5
1 from the outside to the inside, and at this time, suspended substances such as iron oxide fine particles contained in the condensate are captured on the membrane surface of the hollow fiber membrane 51. The filtered water is obtained inside each hollow fiber membrane 51,
The filtered water rises inside each hollow fiber membrane 51 and flows out of the upper end opening of each hollow fiber membrane 51 into the upper chamber 3. It is supplied to the condensate desalination unit of the process. If the filtration process is continued, suspended matter accumulates on the hollow fiber membrane 51, and if the differential pressure of the filtration device exceeds a specified value and the subsequent filtration process is hindered, at this point, a method similar to the conventional method is used. Perform the washing operation.

That is, the valves 6B and 7B of the inflow pipe 6A and the outflow pipe 7A are closed, and the valves 1 of the air inflow pipe 13 and the air release pipe 14 are kept in a state where the lower chamber 2 and the upper chamber 3 are full.
3A and 14A are opened, and compressed air is supplied from the air inlet pipe 13 into the lower chamber 2. The air that has flowed into the lower chamber 2 is temporarily blocked by the distribution mechanism 11, and subsequently becomes bubbles and flows into the skirt portions 52B of the corresponding protection tubes 52 from the respective distribution pipes 11B, and flows through the protection holes 54A through the flow holes 54A. 5
2 and the water is agitated when the bubbles rise in the protective cylinder 52, and the agitating action causes each hollow fiber membrane 51 to vibrate, and the trapped suspended matter is separated from each hollow fiber membrane 51. You. The separated suspended substance flows out to the outside along with water and air bubbles in each hollow fiber membrane module 5 and deposits on the bottom in the closed container 1. On the other hand, the air bubbles flowing into each hollow fiber membrane module 5 flow out of the hollow fiber membrane module 5 through the flow holes 52C, and then the air bubbles flow out of the filtration device through the air vent tube 14.

Further, after performing the above-described scrubbing, the valve 13A of the air inlet pipe 13 is closed while the valve 14A of the air vent pipe 14 is opened, and the drain pipe 1 is closed.
When the valve 15B of 5A is opened, the suspended matter in the closed vessel 1 efficiently flows out from the large-diameter inflow nozzle 6 at the center of the lower end plate 1A to the drain pipe 15A as washing wastewater due to the head difference. Thereby, the filtration performance of each hollow fiber membrane module 5 can be restored.

After the scrubbing operation, the valves 12A and 15B of the air inlet pipe 12 and the drain pipe 15A are provided.
With each open and the other valves closed.
If the compressed air is supplied from the air inlet pipe 12, the compressed air flows into the upper chamber 3, and the filtered water remaining in the upper chamber 3 is caused to flow back into each hollow fiber membrane 51 by the air pressure. The fine particles of the suspended substance clogging the micropores of each hollow fiber membrane 51 are washed out from the inside of each hollow fiber membrane 51 to the outside, and the washing wastewater is drained into a drain pipe 1.
It can be extracted from 5A.

As described above, according to the present embodiment,
Since the inflow nozzle 6 integrated with the drain nozzle is provided at the center of the lower head plate 1A, the number of nozzles attached to the lower head plate 1A can be reduced, and the manufacturing cost of the sealed container 1 can be reduced. Further, since the inflow nozzle 6 is provided in the center of the lower end plate 1A, the condensed water can be evenly dispersed and supplied into the lower chamber 2, and consequently each hollow fiber membrane module 5
And the performance of each can be maintained uniformly throughout.

[0024]

According to the present invention, it is possible to provide a condensate filtration apparatus capable of reducing the manufacturing cost of a closed container and maintaining the filtration performance of each hollow fiber membrane module uniformly throughout. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a condensate filtration device of the present invention.

FIG. 2 is a sectional view showing a hollow fiber membrane module used in the condensate filtration device of the present invention.

FIG. 3 is a sectional view corresponding to FIG. 1 showing an example of a conventional condensate filtration device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Closed container 1A Lower end plate (bottom of closed container) 2 Lower chamber 3 Upper chamber 4 Partition plate 5 Hollow fiber membrane module 6 Inflow nozzle

Claims (1)

[Claims] 1. A partition plate for partitioning the inside of a closed container into a lower chamber and an upper chamber, and a hollow fiber membrane module having an upper end fixed to the partition plate and a lower end hanging down to the lower chamber, wherein a bottom portion of the closed container is provided. In a condensate filtration device in which a condensate nozzle into which condensate flows is attached and a drainage nozzle is attached to the bottom of the closed vessel adjacent to the inflow nozzle, the inflow nozzle integrated with the drainage nozzle is sealed with the A condensate filtration device provided at the center of the bottom of the container.