JPH0815489A - Waste liquid treatment device - Google Patents

Abstract

PURPOSE:To enable the easy purifying treatment of a waste cleaning-liquid used to clean an infiltrative liquid for flaw-detecting infiltration tests. CONSTITUTION:This device treats a waste cleaning liquid used to clean an infiltrative liquid for flaw-detecting infiltration tests sprayed inside an inner wall 5 of a small-diameter tube 3 installed in a lower mirror component 2 of a reactor pressure vessel 1. The device consists of two treatment lines. The primary treatment line 12 has a raw water tank 14 to store waste liquid and purifies the waste liquid discharged from the raw tank 14 by passing it through a filter 18 and an absorbing tower 21. The secondary treatment line 13 makes the fluid treated in the primary treatment line 12 ultrapure water by passing it through an ion-exchange resin and a filter 44, and stores the ultrapure water in a tank 45.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste liquid treatment apparatus, and more particularly, to a cleaning liquid for cleaning a penetrant liquid for penetrant inspection applied to an inner wall of a small-diameter pipe provided in a lower mirror portion of a reactor pressure vessel. The present invention relates to a waste liquid treatment device for treating as waste liquid to obtain ultrapure water.

[0002]

2. Description of the Related Art As shown in FIG. 2, a small-diameter tube (in-core monitor housing) 3 for guiding the insertion of a device for instrumentation is inserted in a lower mirror portion 2 forming the bottom of a reactor pressure vessel 1. And is attached by welding 4, and in order to prevent the inner wall 5 of the small-diameter pipe 3 from being sensitized by the welding heat, a stainless clad layer is formed on the inner wall 5 near the welded portion 4. .

When performing a fluorescent flaw inspection on a defective portion existing on the inner wall 5 of the small-diameter tube 3 including the stainless clad layer, first, the inner wall surface 5 is polished with a flapper or the like, and a predetermined area is indicated by a diagonal line in the figure. When the fluorescent penetrant is sprayed over the entire area and then washed with warm water, the fluorescent penetrant adhering to the surface of the inner wall surface 5 is washed away, and only the penetrant penetrating into the defect is adhered. Become. When this is irradiated with an ultraviolet irradiation lamp and viewed through a camera, only the fluorescent penetrant adhering to the surface defect portion of the inner wall surface 5 emits fluorescence, and the shape and size of the defect portion can be grasped.

[0004]

By the way, the small-diameter pipe 3
When the fluorescent penetrant is sprayed on the inner wall 5 of the container and washed, the cleaning water contains the fluorescent penetrant and metal powder, dust, etc. resulting from polishing, and these are contaminated with radioactivity. Therefore, it becomes radioactive waste liquid.

On the other hand, a large-scale Rad system for disposing radioactive materials is installed in the nuclear power plant. For example, in order to treat the waste liquid, the waste liquid is heated and only the vapor is released to remove the residue. I keep it.

Therefore, when treating the cleaning liquid after cleaning the fluorescent penetrating liquid as a waste liquid, the contamination of the cleaning water is large and the service life of the filter of the Rad system is shortened. After purifying to 100 ppb close to the TOC (water quality value) and converting to ultrapure water, it is about to be tried to evaporate and reduce the volume of the ultrapure water by the Rad system.

The present invention was created in consideration of the above circumstances. It is an object of the present invention to provide a waste liquid treatment apparatus that can easily perform a purification process with a cleaning liquid used as a waste liquid when cleaning a penetrant liquid for penetrant inspection.

[0008]

DISCLOSURE OF THE INVENTION According to the present invention, the cleaning liquid used for cleaning the penetrant for penetrant inspection inspection scattered on the inner wall of the small diameter pipe provided in the lower mirror portion of the reactor pressure vessel is treated as waste liquid. In the apparatus of, the primary treatment line having a raw water tank for storing the waste fluid and purifying the waste fluid discharged from the raw water tank through a filter and an adsorption tower, and the treatment liquid treated in the primary treatment line are ion exchange resins. And a secondary treatment line which is made into ultrapure water through a filter and stored in a tank.

The secondary processing line has a reprocessing line for returning the processing liquid in the tank to the inlet side of the secondary processing line.

[0010]

With this structure, the primary treatment line removes oil and relatively large metal powder from the waste liquid to produce a primary treatment liquid, and the secondary treatment line decomposes proteins and fats to produce ultrapure water. It is something that is done. When the treatment liquid stored in the tank does not reach a predetermined water quality value, the treatment liquid is returned to the inlet side of the secondary treatment line so that a treatment liquid having a constant water quality value is always obtained.

[0011]

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, the waste liquid is used in order to treat the cleaning liquid when the fluorescent penetrant liquid sprayed on the inner wall surface of the small diameter pipe provided in the lower mirror portion of the reactor pressure vessel as waste liquid. The processing device 11 is a primary processing line 1 installed on a trolley.
2 and a secondary processing line (millipoly system) 13 installed on the trolley as well.

In the primary treatment line 11, three raw water tanks 1 for storing the cleaning liquid as a waste liquid when the fluorescent penetrant liquid is cleaned
4, the raw water tank 14 is provided with a liquid level switch 15. A filter 18 is connected to the raw water tank 14 via a first pump 16 and a pressure adjusting valve 17, and the filter 1
8 is connected to a closed adsorption tower 21 having a liquid level switch 19 on the upper part. In the adsorption tower 21, an adsorption mat, an oil adsorbent, activated carbon, filter medium wool and the like are vertically stacked. A drain valve 22 is provided in the lower part of the adsorption tower 21, and an inlet of an inverted U-shaped pipe 23 that is raised upward in an inverted U-shape is connected to the drain valve 22.
On-off valves 26 and 27 that connect the rising portions 24 and 25 on the left and right sides to each other so as to be openable and closable are vertically arranged.

The secondary processing line 13 is connected to the outlet of the inverted U-shaped tube 23, and the inverted U-shaped tube 23 is connected to the secondary processing line 13.
Has a first hermetically sealed tank 32 connected to the outlet of the tank via a solenoid valve 31, a drain valve 33 is connected to the first hermetically sealed tank 32, and a liquid level switch 34
And a stop valve 35 (for bleeding air from the tank) are provided.
An ion exchange resin activated carbon tower 38, an ultraviolet lamp 39 for irradiating the treatment liquid passing through the ion exchange resin activated carbon tower 38 with ultraviolet rays, an ion exchange resin tower 41 and a water quality sensor 42 are sequentially connected via a pump 36 and a pressure regulating valve 37. A membrane filter 44 is connected to the water quality sensor 42 via a three-way valve 43. The membrane filter 44 is provided with a 0.22 μm mesh. A second hermetically sealed tank 45 for storing the treatment liquid that has passed through the membrane filter 44 is connected via a three-way valve 46. A drain valve 47 and a stop valve 48 (for removing air from the tank) are connected to the second closed tank 45.

The upper part of the second hermetically sealed tank 45 is connected to the upper part of the first hermetically sealed tank 32 via an air line 52 having a hepa filter 51. The three-way valve 43 is connected to a water quality holding line 53 that returns the treatment liquid that does not reach a predetermined water quality value to the inlet side of the second pump 37, and the second closed tank 45 is a retreatment line via the third pump 54. 55 is drawn out, and the reprocessing line 55 uses the first closed tank 3 to return the secondary processing liquid to the inlet side of the secondary processing line 13.
It is designed to be connected to the upper part of 2.

Next, the operation of the above embodiment will be described.

Table 1 shows the process data of the waste liquid treatment. The numbers in the left column of this table are the liquid name, temperature, flow rate, TOC and purity at a predetermined point in the waste liquid treatment apparatus 11 shown in FIG. Is shown. That is, the number 1 is in front of the filter 18, and the number 2 is the second closed tank 32.
Of the membrane filter 44,
The number 4 indicates data at the point on the inlet side of the third pump 54 of the reprocessing line 55.

[0018]

[Table 1]

As shown in Table 1 and FIG. 1, the cleaning liquid used for cleaning the inside of the small diameter pipe is stored in the raw water tank 14 of the primary treatment line 12 as a waste liquid. Fluorescent permeation liquid, metal powder, and dust adhering to the piping system, raw water tank 14, etc. are mixed in the waste liquid, and these impurities are removed from the primary treatment line 12
After the purification treatment in step 2, the secondary treatment line 13 is further purified to obtain ultrapure water.

First, the waste liquid stored in the raw water tank 14 is
It is pumped through the pump 16. The TOC of the waste liquid at this time is 1000 ppm or more. This waste liquid is the next filter 1
By passing through 8, the impurities such as relatively large metal powder and mist in the waste liquid are removed. Then, filter 1
The waste liquid that has passed through 8 is transferred to the adsorption tower 21,
In, the oil and fine metal powder of the fluorescent penetrant are adsorbed and removed. The waste liquid that has passed through the adsorption tower 21 is transferred to the first closed type tank 32 through the inverted U-shaped tube 23, but when the head pressure of the left rising portion 24 of the inverted U-shaped tube 23 is large. The lower opening / closing valve 27 is not opened, and as the head pressure decreases, the upper opening / closing valve 26 is sequentially opened to the lower opening / closing valve 27, so that the first treatment line 12 is connected to the first closed tank 32. The waste liquid that has been purified in (1) is slowly transferred little by little as the primary treatment liquid and stored.

The processing liquid discharged from the second hermetically sealed tank 32 is subsequently purified as a secondary processing liquid in the secondary processing line 12. The TOC of the treatment liquid discharged from the second closed type tank 32 drops to 300 ppb, and this treatment liquid passes through the ion exchange resin activated carbon tower 38 via the second pump 36.
The ion exchange resin activated carbon tower 38 exchanges the ions contained in the resin and the ions in the treatment liquid with each other to remove oil and fine metal components of the fluorescent permeation liquid which cannot be completely removed in the primary treatment line 12. When this is irradiated with ultraviolet rays from the ultraviolet lamp 39, organic substances such as fat and protein in the treatment liquid are decomposed, and further, in the ion exchange resin tower 41, the resin ions and the treatment liquid ions are exchanged, and the treatment liquid is The ionized inorganic substances therein are removed. Next, the water quality sensor 42
The water quality inspection is performed by the above, and the treatment liquid that does not reach the predetermined water quality level is returned to the inlet side of the second pump 36 via the water quality holding line 53.

The treated liquid which has reached the predetermined water quality level is 0.2 2
After passing through the membrane filter 44 of μm, it is transferred to the second closed type tank 45. The TOC of the secondary treatment liquid when passing through the membrane filter 44 drops to 100 ppb. The processing liquid in the second hermetically sealed tank 45 is subjected to evaporative volume reduction processing by the Rad system.

If the processing liquid in the second closed type tank 45 is sampled and the TOC is 100 to 300 ppb, the second
The treatment liquid in the hermetically sealed tank 45 is returned to the first hermetically sealed tank 32 via the reprocessing line 55, and is secondarily treated again. Therefore, it is possible to always obtain a treatment liquid having a constant water quality value. In this case, if the sensor detects that the processing liquid in the second closed type tank 45 exceeds 300 ppb and the third pump 54 is driven, the processing liquid can be automatically returned. Further, air moves between the second closed type tank 32 and the third closed type tank 45 due to the elevation of the liquid level, but impurities such as mist contained in this air are removed by the hepa filter 51 and released to the atmosphere. It will not be done.

As described above, in the present invention, the primary treatment line 12 having the filter 18 and the adsorption tower 21 and the secondary treatment line 1 having the ion exchange resin and the filter 44.
Since 3 is combined, the cleaning liquid used for cleaning the fluorescent penetrant liquid can be easily purified as a waste liquid, and a simple and compact waste liquid processing device 11 can be configured.

[0025]

In summary, according to the present invention, the following excellent effects are exhibited.

(1) In claim 1, since the primary treatment line having the filter and the adsorption tower and the secondary treatment line having the ion exchange resin and the filter are combined, the washing liquid used for washing the fluorescent penetrant is The waste liquid can be easily purified as a waste liquid, and a simple and compact waste liquid treatment device can be configured.

(2) In claim 2, since the treatment liquid in the tank is returned to the inlet side of the secondary treatment line, it is possible to always obtain a treatment liquid having a constant water quality value.

[Brief description of drawings]

FIG. 1 is a diagram showing a waste liquid treatment apparatus of the present invention.

FIG. 2 is a sectional view showing a small diameter tube.

[Explanation of symbols]

 1 Reactor Pressure Vessel 2 Lower Mirror 3 Small Diameter Pipe 11 Waste Liquid Treatment Device 12 Primary Treatment Line 13 Secondary Treatment Line 14 Raw Water Tank 18 Filter 21 Adsorption Tower 44 Filter 55 Retreatment Line

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Hamaoka, No. 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa Ishi Kawashima Harima Heavy Industries Co., Ltd. Engineering Center

Claims (2)

[Claims] 1. An apparatus for treating a cleaning liquid as a waste liquid when the penetrant liquid for penetrant inspection inspection scattered on an inner wall of a small-diameter pipe provided in a lower mirror portion of a reactor pressure vessel is treated as a waste liquid. A primary treatment line having a raw water tank for storing and purifying the waste liquid discharged from the raw water tank through a filter and an adsorption tower, and the treatment liquid processed in the primary treatment line is made into ultrapure water through an ion exchange resin and a filter. And a secondary treatment line for storing in a tank. 2. The waste liquid treatment apparatus according to claim 1, wherein the secondary treatment line has a retreatment line for returning the treatment liquid in the tank to the inlet side of the secondary treatment line.