JP2723323B2 - Ceramic filtration equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention is suitable for condensate, treated water and wastewater of a thermal power plant or a nuclear power plant, or radioactive waste liquid from a reprocessing plant. It relates to a filtration device for purifying.

(Prior Art) In general, in a power plant, for example, a nuclear power plant, it is necessary to suppress and remove the generation of corrosion products in radioactive waste liquid or condensate water as radiation reduction measures. Further, in a thermal power plant, it is necessary to suppress or remove corrosion products in condensate water in order to improve power generation efficiency. Furthermore, in the reprocessing plant,
The treated water contains insoluble solids (hereinafter referred to as cladding) such as iron oxide attached to the outer surface of the spent fuel, and the treated water is a waste liquid having a very high radioactivity concentration. For this reason, it is necessary to remove the clad in the treated water also in this reprocessing plant.

As a means of treating water in each such plant,
As shown in FIG. 11, water (suspension water) containing suspended matter such as clad collected in the collection tank 1 is sent to the precoat filter 3 by the transfer pump 2 and filtered, and then the desalination device 4 is used.
12, or, as shown in FIG. 12, the suspension is sent to a clad separator 5 which is also a centrifugal separator by a transfer pump 2 to separate the clad, and then desalted by a desalter 4. Alternatively, as shown in FIG. 13, after the suspended water is sent to the hollow fiber membrane filter 6 made of a porous polymer material by the transfer pump 2 to separate the clad,
What is desalted by the desalination device 4 is used.

(Problem to be Solved by the Invention) The pudding coat filter 3 shown in FIG. 11 described above is obtained by pre-coating a pre-coated material such as diatomaceous earth or powdered ion-exchange resin on a medium such as a stainless steel mesh. Then, filtration is performed by passing through the precoat layer. However, the conventional example shown in FIG. 11 using the precoat filter 3 has the following problem.

(1) Clogging is likely to occur in the precoat layer, and the frequency of the backwashing operation to recover the clogging is high.

(2) During the backwashing operation, a large amount of secondary waste is generated because the precoat material is peeled off together with the filtered clad.

(3) Since the precoat filter 3 requires a precoat operation, extra devices such as a precoat material preparation tank 7, a precoat pump 8, and a holding pump 9 are required, and the system becomes complicated.

Next, in the conventional example shown in FIG. 10 in which the clad separator 5 is used, separation is performed by using a difference in the specific gravity of the clad by a separation plate type centrifugal separator rotating at a high speed (3000 to 5000 rpm). However, particularly in recent nuclear power plants, the water quality in the furnace has been improved due to the technological progress of water chemistry, and therefore, cladding components such as amorphous iron components having relatively small specific gravity have increased. In addition, since the cladding particularly attached to the fuel has a relatively high radiation level even in a nuclear power plant, the radioactivity concentration of water generated from the spent fuel transport cask is relatively high at about 1 to 2 μCi / cc. In this case, no secondary waste is generated since no precoat material is used, but there are the following problems.

(1) The clad having a small specific gravity difference or small particle size cannot be sufficiently removed.

(2) Since the clad separator 5 is a rotating machine, it needs to be disassembled and inspected. In addition, during the overhaul, the worker may be exposed to radiation.

Further, in the conventional example of FIG. 13 using the hollow fiber membrane filter 6, a filter formed by forming a polymer compound such as polyethylene, polyvinyl alcohol or polyvinyl acetate into a porous hollow fiber shape is used. In this conventional example, since no precoat material is used, the generation of secondary waste is small even by backwashing. Furthermore, the water quality after treatment is good,
The cladding on the filtration outlet side has an excellent feature that it is below the detection limit and that no maintenance work is required.

However, since a polymer material is used, there is a problem in radiation tolerance, and a practical use limit is reached when an integrated dose of about 10 ⁵ to 10 ⁷ rad is received. For this reason, for example, when processing a fluid having a relatively high radioactivity concentration such as water generated from a spent fuel transport cask, the design life is reached in about 1 to 2 months, and practically There is a problem that is not.

Further, when replacing the hollow fiber membrane filter, the operator must handle the filter contaminated with a high dose, and there is a problem that the exposure dose may increase.

The present invention has been made in consideration of the above problems, and can remove the clad below the detection limit, and has excellent radiation resistance and does not generate secondary waste even by backwashing.
An object of the present invention is to provide a filtration device that can reduce the amount of waste, simplify maintenance work, and reduce radiation exposure of workers.

[Configuration of the invention]

(Means for Solving the Problems) According to the present invention, a partition plate is arranged in a tank container of a filtration tank, and the inside of the tank container is partitioned into first and second primary side chambers and a secondary side chamber. A filtration filter is supported in the side chamber by the partition plate, and the tank container has a backwash water outlet opening to the first primary side chamber and connected to a suspension water inlet and a backwash water receiving tank. In a filtration device in which a filtered water outlet nozzle connected to a filtered water receiving tank is formed, the filtration filter is a ceramic filter, and the filtration filter is a ceramic filter. The tank container is characterized in that a washing water nozzle opened to the second primary side chamber and connected to a washing water pipe, and a vent nozzle is formed above the second primary side chamber.

(Operation) Therefore, according to the filtration device of the present invention, when water generated in the plant or suspended water such as condensate is guided to the filtration device and passes through the ceramic filter,
The passage of the cladding in the suspension water is impeded and this cladding is removed and filtered. Since the ceramic filter is porous and its pore size can be selected to be sufficiently small, the cladding in the suspension water can be separated and removed almost completely.

In addition, the ceramic filter has a high resistance to radioactivity in water, and no secondary waste is generated even if a backwashing scan is performed to recover the filtering ability, so that maintenance work is not required. For this reason, it is possible to avoid radiation exposure of workers during maintenance work.

Furthermore, the filtered water is led from the filtered water receiving tank to the secondary chamber in the tank via the filtered water outlet nozzle as washing water,
In addition to the first-step cleaning in which the cleaning water flows from the outside to the inside of the ceramic filter for cleaning, a second-step cleaning is performed. In the cleaning in the second step, after the cleaning in the first step is performed, the cleaning water is guided from the cleaning water pipe through the cleaning water nozzle and the second primary chamber to the secondary chamber, and the cleaning water is supplied to the inside of the ceramic filter. To clean the inside of the filter well. As a result of performing the first and second steps of cleaning, the cleaning efficiency is improved, and the filtration capacity of the filtration tank can be favorably maintained for a long time.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a filtration system to which an embodiment of the filtration device according to the present invention is applied, and FIG. 2 is a block diagram showing the filtration device of FIG.

As shown in FIG. 1, turbid water such as treated water or condensate generated in the plant is collected and stored in a collection tank 10. The collection tank 10 is connected to a filtration device 13 via a suspension water transfer pipe 12 provided with a transfer pump 11. The suspension water is filtered by the filtration device 13. A filtration water transfer pipe 14 is connected to the filtration device 13, and a desalination device 15 is disposed on the filtration water transfer pipe 14. The desalting device 15 removes ionic components in the filtered water filtered by the filtering device 13.

As shown in FIG. 2, the filtration device 13 includes a filtration tank 16,
Filtered water receiving tank 17, backwashing water receiving tank 18, and washing water piping
It has 19 grades.

The filtration tank 16 is a vertically cylindrical closed container that can be opened and closed at a flange portion. Two upper and lower partition plates 21 are arranged in the filtration tank 16, and a large number of ceramic filters (hereinafter, referred to as ceramic filters) 22 are supported by these two partition plates 21. In the tank container 20, a first primary chamber 23 is formed at the lowermost part, a second primary chamber 24 is formed at the uppermost part, and a secondary chamber 25 is formed at the center part by the partition plate 21. The filter 22 is provided in the secondary chamber 25.

The tank container 20 is formed with a nozzle that opens into the first primary side chamber 23 and serves as both the suspension water inlet 26 and the backwash water outlet 27. The suspension water transfer pipe 12 is connected to the suspension water inlet 26, and the suspension water is guided into the first primary side chamber 23 during the filtration operation of the filtration tank 16. An inlet valve 28 is arranged in the suspension water transfer pipe 12.

Further, a backwash water discharge pipe 29 is connected to the backwash water outlet 27. In this backwash water discharge pipe 29, a backwash water discharge valve 30 and a backwash water receiving tank 18 are sequentially arranged from the filtration tank 16 side. A vent pipe 33 in which a demister 32 is arranged is connected to an upper part of the backwash water receiving tank 18.

Next, a filtered water outlet nozzle 34 is formed in the tank container 20 so as to open into the secondary side chamber 25.
The filtered water transfer pipe 14 is connected to. This filtered water transfer pipe
14 has a filtered water receiving tank 17 and an outlet valve 37,
They are arranged sequentially from the 16 side. The suspension water in the first primary chamber 23 of the filtration tank 16 is filtered through the ceramic filter 22 in the secondary chamber 25, and the filtered water is primarily stored in the filtered water receiving tank 17.

A backwash air pipe 38 is connected between the filtered water receiving tank 17 and the outlet valve 37 in the filtered water transfer pipe 14. A backwash air valve 39 and an air filter 40 are sequentially arranged on the backwash air pipe 36 from the side of the filtered water receiving tank 17, and the backwashing air valve 39 and the air filter 40 enter the filtered water receiving tank 17 at the time of the first step of backwashing described later. Compressed air is supplied.

Further, a cleaning water nozzle 41 is formed in the tank container 20 so as to open to the second primary side chamber 24, and the cleaning water pipe 19 is connected to the cleaning water nozzle 41. The washing water pipe 19 is provided with a washing water valve 42, and washing water is supplied from the washing water pipe 19 into the second primary side chamber 24 at the time of back washing in a second step described later.

FIG. 3 shows the internal structure of the tank container 20. The ceramic filter 22 is sandwiched by two partition plates, an upper partition plate 21a and a lower partition plate 21b, through packings 57 at both ends. The interval between the two partition plates is adjusted by a plurality of tie rods 55 according to the length of the ceramic filter 22. This tie rod 55 is used for the upper partition 21
a, are fixed to the lower partition plate 21b with bolts 56, respectively.

The upper partition 21a and the lower partition 21b have primary chambers 23 and 24, respectively.
An O-ring 54 is provided for sealing the secondary chamber 25.

Further, the tank container 20 is provided with a seal ring 59 in order to more reliably seal the O-ring 54.

A hanging tool 53 is attached to the upper partition plate 21a for maintenance work of the ceramic filter 22.

By the two partition plates 21a and 21b and the tie rod 55,
A ceramic filter assembly 58 is configured. The ceramic filter assembly 58 is housed inside the tank container 20, and does not constitute a pressure-resistant member of the tank container 20.

The upper lid 60 of the tank container 20 is fixed with a stud 52.

A vent nozzle 51 is provided at the uppermost part of the second primary chamber 24 of the tank container 20, and has a structure capable of discharging the air layer accumulated at the upper part.

By the way, the above-mentioned ceramic filter 22 described later is
And are arranged in a liquid-tight manner. Each ceramic filter 22 is formed in a hollow tube shape as shown in FIG. 4, or a polygonal or cylindrical porous ceramic matrix shown in FIG. 5 (FIG. 4 shows an example of a hexagonal prism). Any of a number of holes 70 penetrating both end surfaces in 70 may be employed. Here, arrows A and A in FIG. 4 and FIG.
B indicates the flow of water during the filtration operation of the filtration tank 16.

Alumina (Al ₂ O ₃ ) as the ceramic filter 22
A porous material consisting of This ceramic filter
The overlayer 22 has a multilayer structure of at least two layers as shown in FIG. That is, it is composed of a primary layer (microporous layer) C in contact with the suspension water and a secondary layer (porous layer) D in contact with the filtered water. Most of the transmission holes of the fine holes C are several μm.
m and smaller than the diameter of the cladding in the suspension water known to be m. Further, the permeation holes of the pore layer D are as follows:
To reduce fluid resistance when filtered water passes through,
The pores are larger in pore diameter than the fine pores. As an example of specific numbers, it is preferable that the diameter of the fine pores is selected to be about 0.1 to 0.5 μm and the diameter of the fine pores is selected to be about 3 to 30 μm.

That is, FIG. 7 shows the results obtained by performing a low-pressure filtration test with a simulated liquid prior to the execution of this example in order to select the pore diameter of the fine pores. FIG. 7 shows the situation where the ratio of the overspeed to the theoretical treatment speed changes as the cumulative treatment amount of the suspension water increases when the operation of the filtration device 13 is continued while repeating the backwashing. It shows the result of an experiment while changing. When the pore diameter of the micropores is 0.2 μm (indicated by ◇ in the figure), the filtration rate is substantially constant even after repeated backwashing, but when the pore diameter of the micropores becomes 0.8 μm (indicated by ◆ in the figure), the filtration rate gradually increases. It can be seen that the filtration rate decreases. From the particle size distribution data of the cladding in water of a nuclear power plant and this experimental result, good results were obtained when the preferred average diameter of the micropores was set to about 0.1 μm to 0.5 μm. In addition, when the average diameter of the fine pores was adopted, the average diameter of the fine pores was about 3 μm to 30 μm, and good results were obtained.

The materials of the wetted parts of the filtration tank 16, the filtered water receiving tank 9, the air filter 40 and the various pipes connected to these in the filtration device 13 prevent clogging of the ceramic filter 22 at the time of reverse line due to generation of corrosion products. Stainless steel is optimal to prevent. Since the rubber lining material, the flaking lining and the like contain a polymer material, the material may be changed by the radiation (mainly γ-ray) of the suspension water, which is not preferable because there is a problem in durability when used for a long time.

Further, as a filter of the air filter 40, a ceramic filter or a porous polymer hollow fiber membrane filter is used, and the backwash water discharge valve 30 is a ball valve with a quick exhaust.

 Next, the operation will be described with reference to FIG. 1 and FIG.

During normal filtration processing, the inlet pump 28 and the outlet valve 37 are opened, the backwash water discharge valve 30 and the backwash air valve 39 are closed, and the transfer pump 11 is operated. Then, the suspension water stored in the collection tank 10 is supplied under pressure to the filtration device 13, and the suspension water is
From the suspension water inlet nozzle 26 of the filtration tank 16 to the first primary side chamber
23 and then passes through the ceramic filter 22 in the directions of arrows A and B in FIGS. At this time,
All the claddings contained in the suspension water and having a certain diameter determined by the pore diameter of the micropores are all blocked.

The filtered water that has passed through the ceramic filter 22 is
After that, it is guided to the desalination device 15 by blowing the filtered water transfer pipe 14 and the filtered water receiving tank 17. When the filtered water passes through the desalting device 15, the ionic components in the filtered water are removed. Removal of the clad by this filtration device 13,
The quality of the water flowing through the plant is always kept at a constant level in combination with the removal of the ionic components by the desalination unit 15.

When the above-mentioned filtration process is continued for a long time by the filtration device 13, a clad cake layer is deposited on the primary side (microporous layer side) of the ceramic filter 22 and, as a result,
The filtration speed decreases, and the filtration efficiency of the filtration device 13 deteriorates.
When this occurs, the ceramic filter 22 is backwashed to remove the cake layer, and the filtration efficiency is restored.
This backwash has two steps.

When performing the backwash of the first step, first, the inlet valve
After the filtration process is stopped by closing the valve 28 and the outlet valve 37, the backwash air valve 29 is opened and 3 to 9 kg /
The compressed air of about ² cm ² is guided into the filtered water receiving tank 17 to pressurize the filtered water. Next, the backwash water discharge valve 30 is opened. Then, the pressurized filtered water in the filtered water receiving tank 17 is
Arrows in FIG. 4 and FIG.
It passes in the opposite direction to A and B and flows into the backwash water receiving tank 18 at a stretch. At this time, the clad cake layer adhering to the ceramic filter 22 peels off.

The back washing in the second step is performed immediately after the back washing in the first step. That is, immediately after the back washing in the first step, the washing water valve 42 is opened, and washing water having a flow rate of about 2 to 5 m / s is passed through the washing water pipe 19 through the washing nozzle 41 to the second filter of the filtration tank 16. It is supplied into the primary side chamber 24. Then, the washing water is directly guided to the inner surface on the primary side (microporous layer side) of the ceramic filter 22, and the cake layer peeled off from the inner surface by the back washing in the first step is washed off. This cleaning of the inner surface of the ceramic filter 22 is referred to as film surface cleaning. afterwards,
The wash water flows from the first primary side chamber 23 of the filtration tank 16 into the backwash water receiving tank 18 via the backwash water outlet nozzle 27.

In the first step, the clad cake layer deposited on the inner surface of the ceramic filter 22 is peeled off, and in the second step, the peeled cake layer is washed off to complete the backwash. After this backwash, the backwash air valve 39,
The backwash water discharge valve 30 and the wash water valve 42 are closed, the inlet valve 28 and the outlet valve 37 are opened, and the operation returns to the normal filtration operation.

When it is difficult to recover the filtration speed even if the filtration operation is continued for a long time and the backwash is performed, and the filtration efficiency is reduced, the ceramic filter 22 is replaced.

8 (a) to 8 (c) are flowcharts showing a method of replacing a ceramic filter.

This flowchart shows a ceramic filter used at a nuclear facility and contaminated with high radioactivity.
The work procedure is as follows. First, after removing the hatch that separates the filter tank chamber 66 from the work area 67, the worker 62 in the work area 67 uses the special bolt wrench 61 to remove the tank container 20 as shown in FIG. Remove the stud bolt 52 nut from the top lid 60 part.

Next, as shown in FIG. 8 (b), after removing the upper lid 60,
In the hanging tool 53 at the top of the ceramic filter assembly 58,
The suspended automatic gripper 68 is attached by the hoist 63, and the worker 62 in the work area 67 raises the used ceramic filter assembly 58 by remote control.

Then, as shown in FIG. 8 (c), the pulled-up ceramic filter assembly 58 is stored in the transfer container 64 which has been previously arranged near the tank container 20 while being fixed to the partition plate 21. After that, the waste disposal facility (not shown) with the transfer container 64
Transfer to

Since the ceramic filter assembly 58 does not constitute a pressure-resistant member of the tank container 20, there is no problem in disposing of parts such as the partition plate 21 in government offices.

When a new ceramic filter 22 is to be stored in the tank container 20, a ceramic filter assembly 58 previously assembled in a factory or the like in the form of a ceramic filter assembly 58 shown in FIG.
Transfer to tank 66 and reverse the tank
Store in 20.

According to the above embodiment, since the filtration layer of the ceramic filter 22 in the filtration tank 16 has a multilayer structure, the suspended water is thinned with fine pores having a sufficiently small pore diameter as shown in FIG. After the cladding is effectively captured by the overlayer (microporous layer) C, it passes through a filtration layer (pore layer) D having pores having a larger diameter than the micropores and having a small fluid resistance. A high filtration flow rate can be obtained. Therefore, it is possible to remove the clad in the waste liquid generated from the power plant or the highly radioactive treated water generated from the condensate and reprocessing plant to almost the detection limit or less regardless of the water quality. For this reason, the water quality after the filtration treatment is improved, the radioactivity level is reduced, and it is more effective when reused as plant water.

In the ceramic filter 22 in the filtration tank 16, the filtration layer having micropores (micropore layer) is thin and the pore diameter of the micropores is sufficiently small, so that the clad does not enter the inside of the filtration layer. The filtration layer (pore layer) having the pores of the ceramics filter 22 has a low fluid resistance. From these facts, even if the filtration tank 16 performs the filtration operation for a long time, the decrease in the filtration speed is small.

Further, the ceramic filter 22 can be used not only for backwashing but also for its repeated use due to its high radiation resistance. Further, the ceramic filter 22 has no possibility of generating secondary waste during backwashing. Therefore, the frequency of replacing the ceramic filter 22 is low, and the frequency of maintenance work is very low.

In addition, the filtration efficiency drops significantly,
Even if replacement of 22 is necessary, the top cover of tank container 20
Since the removal of the 60 and the removal of the ceramic filter assembly 58 can be performed by remote control, exposure of workers during maintenance work can be reduced. For this reason, in a filtration device for treating suspended water, particularly suspended water generated from a spent fuel transport cask, when replacing the high-dose contaminated ceramic filter 22 in the filtration tank 16, the radiation of workers may be reduced. Exposure can be significantly reduced.

Further, as described above, since the ceramic filter 22 does not generate secondary waste during backwashing, the number of drums for storing radioactive waste including the secondary waste can be significantly reduced.

The backwashing of the filtration tank 16 consists of two steps.
The cake layer of the clad deposited from the inner surface of the microporous layer is peeled off. Then, after performing the first step of backwashing, the second step of backwashing is performed to wash (film surface cleaning) the clad cake layer peeled from the inner surface of the ceramic filter 22. Since the first and second steps of backwashing are performed in this way, compared to the case of only the first step of backwashing,
The filtration capacity of the filtration tank 16 can be significantly improved, and the backwashing efficiency can be improved to maintain good filtration performance for a long time.

In the first step of backwashing, since the dust in the compressed air supplied into the filtered water receiving tank 17 through the backwashing air pipe 38 is removed by the air filter 40, the ceramic filter 22 has pores. There is no clogging in the filtration layer (pore layer). In addition, at the time of the first and second steps of backwashing, the backwashing water is swiftly discharged into the backwashing water receiving tank 18, but the mist in the discharged backwashing water is removed by the demitas 32. Therefore, entrainment can be prevented.

FIG. 9 is a block diagram showing a filtration device to which another embodiment of the filtration device according to the present invention is applied. In the other embodiments, the same parts as those in the above embodiment are denoted by the same reference numerals, and the description is omitted.

The filter 43 in the other embodiment is different from the filter 13 in the previous embodiment in terms of configuration in that the cleaning air is supplied to the cleaning water nozzle 41 of the filtration tank 16 from the downstream side of the air filter 40 of the backwash air pipe 38. The pipe 44 is connected, and a cleaning air valve 45 is provided in the cleaning air pipe 44. The filtration device 43 in the other embodiment is the same as the filtration device 13 in the above embodiment in the normal operation and the backwash in the first step, and differs only in the backwash in the second step.

That is, immediately after the back washing in the first step, the washing water valve 42 is opened, and washing water having a flow rate of about 2 to 5 m / s is guided to the washing nozzle 41 of the filtration tank 16 through the washing water pipe 19, The cleaning air valve 45 is opened, and air is introduced into the cleaning nozzle 41 via the cleaning air pipe 44. Wash water and air are mixed at the wash water nozzle 41, and this mixed flow is supplied to the filtration tank.
It is supplied to the inner surface of the ceramic filter 22 through the second primary chamber 24 of 16. The mixed flow separates the cake layer peeled from the inner surface of the ceramic filter 22 in the backwash of the first step,
The flow of the mixed flow and the swaying of the bubbles in the mixed flow effectively wash off and restore the filtering ability of the ceramic filter 22. Thereafter, the mixed flow is discharged into the backwash water receiving tank 18 via the first primary side chamber 23 and the backwash water outlet nozzle 27.

FIG. 10 is a graph showing a situation where the permeation flow rate passing through the ceramic filter 22 changes according to the number of backwashing when the operation of the filtration devices 13 and 43 is continued. According to FIG. 10, in the case of the filtration device 13 indicated by the broken line E, the filtration flow rate, ie, the overflow, decreases with an increase in the number of backwashing, but in the case of the filtration device 43 indicated by the solid line F, the filtration flux Hardly decreases. Thus, the filtration device 43 in this other embodiment is
In this case, the membrane surface cleaning in the second step is performed more favorably than the filtration device 13 of the above embodiment, so that the backwashing efficiency is improved and the filtration capacity of the filtration tank 16 can be further improved.

In both of the above embodiments, a description has been given of the ceramic filter 22 in which the filtration layer having micropores (micropore layer) is provided on the inner surface of the ceramic filter 22. May be provided. In both embodiments, the filtered water in the filtered water receiving tank 17 is used for backwashing. However, the volume of the secondary chamber 25 of the filtration tank 16 is increased to backwash the filtered water in the secondary chamber. Used for
The filtered water receiving tank 17 may be omitted.

〔The invention's effect〕

According to the above embodiment, since a ceramic filter is employed as a filtration filter in the filtration tank, the clad contained in the suspension water generated in various plants can be removed to substantially below the detection limit, and after the treatment, Water can be effectively reused in nuclear power plants, and at the same time radioactivity in suspended water can be reduced.

In addition, ceramic filters have high radiation tolerance,
Furthermore, secondary waste is not generated by the backwashing operation,
The frequency of maintenance work of the ceramic filter is extremely reduced, and the radiation exposure of workers can be reduced.

Further, since the washing vessel is connected to the tank container and opened to the second primary side chamber, backwashing of the filtration tank can be performed in two steps, so that the backwashing efficiency can be improved and the filtration tank can be improved. Of the filter can be improved.

In addition, during maintenance work such as replacement of a used ceramic filter, the upper cover of the tank container can be removed and the ceramic filter assembly can be removed by remote control, so that the radiation exposure of workers can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a filtration system to which an embodiment of the filtration device according to the present invention is applied, FIG. 2 is a block diagram showing the filtration device of FIG. 1, and FIG. 3 is shown in FIG. FIG. 4 is a longitudinal sectional view of a filtration tank, and FIGS. 4 and 5 are perspective views showing the shape of a ceramic filter housed in the filtration tank of FIG.
FIG. 6 is a schematic diagram showing the filtration layer of the ceramic filter of FIGS. 4 and 5, FIG. 7 is a graph showing the experimental results of the effect of the filtration layer of the ceramic filter shown in FIG. 6,
8 (a) to 8 (c) are schematic diagrams sequentially showing a method of replacing a ceramic filter, FIG. 9 is a block diagram showing a filtration apparatus to which another embodiment of the present invention is applied, and FIG. 9
FIG. 11 is a graph showing the operation and effect of the filtration device shown in FIG. 2 in comparison with the filtration device shown in FIG. 2, and FIGS. 11 to 13 show a conventional treatment device for water generated in a power plant and a reprocessing plant, respectively. FIG. 16 Filtration tank, 20 Tank container 21 Partition plate 22, Ceramic filter 23 First primary chamber, 24 Second primary chamber 25 Secondary chamber, 26 Turbid water inlet 27 Backwash water outlet 41 Wash water nozzle 51 Vent nozzle

Claims (1)

(57) [Claims] 1. A partition plate is arranged in a tank container of a filtration tank, and the inside of the tank container is partitioned into a first and a second primary chamber and a secondary chamber, and a filter is provided in the secondary chamber. In addition to being supported by the plate, the tank container is formed with a nozzle that opens to the first primary side chamber and also serves as a suspension water inlet and a backwash water outlet to which a backwash water receiving tank is connected. Further, in the filtration device which is opened to the secondary side chamber and has a filtered water outlet nozzle connected to the filtered water receiving tank, the filtration filter is a ceramic filter, and the tank container further includes A ceramic filtration device, wherein a cleaning water nozzle opened to the second primary side chamber and connected to the cleaning water pipe and a vent nozzle is formed above the second primary side chamber.