JPH0786556B2 - Waste liquid storage device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention relates to a waste liquid storage device that stores a waste liquid mixed with a solid precipitate in a stirrable manner, and is particularly discharged from a nuclear power generation facility. The present invention relates to a waste liquid storage device that stores and agitates waste liquid.

(Prior Art) A nuclear power plant is equipped with a radioactive liquid waste treatment facility, and by this facility, the radioactive liquid waste generated at the power plant is treated and safely managed. Radioactive waste liquid is generated from equipment drain water from various equipment, waste powder resin generated from condensate demineralizer, etc., waste resin generated from ion exchange resin of condensate demineralizer, etc. It is concentrated waste liquid or clad water that is generated. These radioactive waste liquids are collected in the radioactive waste liquid storage device housed in the building of the nuclear power generation facility and temporarily held.

Ion exchange resin, clad, and other relatively small solid particles are mixed in the radioactive waste liquid.When these solid particles are stored as radioactive waste liquid, they settle in the storage container of the radioactive waste liquid treatment device, and Deposited on the bottom. The radioactive waste liquid stored in the storage container is transferred to a regenerator for the purpose of reuse and subjected to chemical treatment such as filtration or desalting. However, in order to transfer the radioactive waste liquid to the regenerator, it is necessary to stir in advance in the storage container to raise the precipitate and mix the precipitate with the supernatant waste liquid (mother liquor). Therefore, a stirrer is installed in the radioactive waste liquid treatment apparatus, and the stirrer stirs the stored radioactive waste liquid.

Various types of mechanisms of this stirring device are adopted. For example, by immersing the entire stirring pump or only its propeller part in the bottom of the storage container and directly stirring the radioactive waste liquid by a motor drive, or by installing the stirring pump device outside the storage container, The one that jets the jet discharge liquid toward the bottom of the storage container and stirs the precipitate is put to practical use. As an example of the latter waste liquid storage device having a stirring function, there is an invention disclosed in Japanese Patent Laid-Open No. 61-83999 (hereinafter, referred to as an invention disclosed in this publication).

Although such a gazette-published invention has the advantage that the precipitate at the bottom of the storage container can be efficiently stirred without installing any dynamic stirring mechanism inside the storage container, It also has some drawbacks.

That is, since no consideration is given to disassembling the double pipe portion at the bottom of the storage container, it is difficult to check the condition of corrosion and wear of the wetted portion of the double pipe portion, and the inner pipe cannot be replaced.

Further, in the annular flow path constituted by the outer pipe and the inner pipe, that is, in the portion that changes the direction of the liquid flow at a substantially right angle, the liquid line changes abruptly, so that the pressure loss increases. When the pressure loss becomes extremely large, it is possible that eddy current causes harmful vibration and cavitation erosion in this vicinity.

Furthermore, since the inner tube opens vertically to the bottom of the container,
The suction vortex makes it easier for air to be drawn into the inner tube, which may adversely affect the pump performance. In order to remove the harmful effect on the pump performance, it is necessary to keep the stirring stop liquid level high in the storage container.
This may reduce the actual capacity (effective capacity) of the waste liquid storage device (in other words, increase the ineffective storage capacity).

(Problems to be Solved by the Invention) As described above, in the invention disclosed in the publication representative of the conventional waste liquid storage device, the condition of corrosion and wear of the liquid contact part of the double pipe part at the bottom of the storage container is checked. However, it has the disadvantage that the inner tube cannot be replaced.

This invention was made in consideration of the above circumstances,
Easily inspect the condition of corrosion and wear of the wetted part of the double pipe
It is an object of the present invention to provide a waste liquid storage device that can be repaired, can easily replace the inner pipe as necessary, and can efficiently perform maintenance and inspection of the device.

[Structure of Invention]

(Means for Solving the Problem) The present invention relates to a storage container for storing a waste liquid such as radioactive waste liquid, an injection guide element provided at the bottom of the storage container to form an emotional ejection port, and the storage container. A stirring pump externally arranged and connected to a pump discharge pipe and a pump suction pipe, sucks the waste liquid in the storage container by the operation of the stirring pump, and pumps it from the emotional ejection port of the ejection guide element. In a waste liquid storage device configured to radially inject a pressure liquid along the bottom surface of a storage container, the waste liquid storage device is arranged at the bottom of the storage container and connected to the pump discharge pipe, and a pump pump in the pump discharge pipe is installed. An outer pipe that guides the pressure liquid to the injection guide element, and a waste liquid that is detachably accommodated in the outer pipe and is connected to the pump suction pipe and is stored in the storage container. And an inner pipe for guiding the pump to the suction pipe, and an upper end portion of the inner pipe is provided with a suction guide element for restricting the inflow of the waste liquid from directly above and guiding the waste liquid from a substantially lateral direction and the lower end of the inner pipe. A large diameter part is formed in the part and is inserted and connected to the outer pipe,
The suction guide element has a small hole at the center thereof for communicating the inside and the outside.

(Operation) Therefore, according to the waste liquid storage device of the present invention, the inner pipe for guiding the waste liquid in the storage container to the stirring pump is provided inside the outer pipe for guiding the pump pressurizing liquid from the stirring pump to the injection guide element. The inner pipe is detachably housed in the outer pipe because the inner pipe is detachably housed in the outer pipe.
The wetted part of the heavy pipe can be easily inspected and maintained, and the inner pipe can be replaced easily, so that the maintenance and inspection of the device can be efficiently performed.

Further, since the large diameter portion is formed at the lower end of the inner pipe and is inserted into the outer pipe, the pressure of the pump pressurizing liquid is applied to the large diameter portion, and a force for urging the inner pipe downward is generated.

Further, since the small hole that communicates the inside and the outside is provided at the center of the upper part of the suction guide element, when discharging the waste liquid, the waste liquid is not left on the upper part of the suction guide element. Then, the size of the spiral generated on the surface of the waste liquid due to the suction from the suction guide element can be reduced.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is an overall sectional view showing a first embodiment of the waste liquid storage device according to the present invention, and FIG. 1 is an enlarged sectional view of a main part of FIG.

The waste liquid storage device 1 has a storage container 3 housed in a concrete skeleton 2 of a nuclear power generation facility building. This storage container 3 is a cylindrical storage tank, and the concrete frame 2
It is supported in the housing chamber 4 of FIG. The support skirt 5 is erected on the floor surface 6 of the storage chamber 4. The bottom surface of the storage container 3 is formed into a smooth curved surface, and the outer pipe 7 shown in FIG. 1 is connected to the storage container 3 near the center of the bottom by liquid contact or the like.

The top part of the outer pipe 7 opens into the storage container 3, while the inner pipe 8 is inserted near the center of the cross section of the pipe to form a double pipe structure. The outer pipe 7 has a spherical shape whose lower end is one step larger than the other, and the spherical portion 9 has a branch port 10 in the horizontal direction.
Is formed. The branch port 10 is connected to the pump discharge pipe 11 by welding or the like. An annular flow path 12 is formed by being surrounded by the outer pipe 7 including the spherical portion 9 and the inner pipe 8. In this annular flow path 12, the flow direction of the pump pressurized liquid from the pump discharge pipe 11 is converted into a substantially right angle.

Furthermore, a branch port 13 is formed vertically downward in the spherical portion 9 of the outer tube 7. A connection pipe 14 is connected to the branch port 13 by welding or the like. The connecting pipe 14 is, as shown in FIG.
Two or more branches are made in the vicinity of the floor surface 6, and a pump suction pipe 15 and a transfer pipe 16 are connected to each branch pipe.

On the other hand, as shown in FIG. 1, the inner pipe 8 projects from the top of the outer pipe 7, terminates, and opens to the storage container 3. On the projecting portion of the inner tube 8, an injection guide element 17 is formed integrally with the inner tube 8 to cover the top opening of the outer tube 7 with a space. The jet guide element 17 has an inverted dish shape or an umbrella disk shape, and a plurality of radial guide blades 18 are provided on the lower surface in the circumferential direction. Further, the ejection guide element 17 is detachably fixed to the bottom of the storage container 3 by a mounting bolt 19. With such an injection guide element 17, the outer pipe 7
Is closed at its top in the axial direction and is opened over the entire circumference. An annular ejection port 20 is formed between the bottom of the storage container 3 and the outer peripheral edge of the ejection guide element 17.

A suction guide element 21 is detachably fixed to the injection guide element 17 at the upper end of the inner pipe 8 by a mounting bolt 22. The suction guide element 21 is in the shape of an inverted hat and has a suction port 24 that is open all around the horizontal direction. In addition, the suction guide element 21
A plurality of suction guide vanes 23 are provided inside. Further, a small hole 25 is formed at the top of the suction guide element 21, and the waste liquid in the storage container 3 is sucked in through the small hole 25.
It is installed so that it can flow directly into 21.

The lower end portion 26 of the inner pipe 8 is formed in a truncated hollow conical shape, and is fitted into the lower portion of the spherical portion 9 of the outer pipe 7. Lower end of inner tube 8
The outer diameter of 26 is set to be slightly smaller than the inner diameter of the lower portion of the spherical portion 9, and a gap 27 is formed between the lower end portion 26 and the lower portion of the spherical portion 9.
Is formed. The lower end 26 of the inner tube 8 has a truncated hollow conical shape that is sharpened downward, so that the inner tube 8 is provided so that it can be easily mounted from the inside of the storage container 3 into the outer tube 7.

On the other hand, as shown in FIG. 2, the pump suction pipe 15 connected to the communication pipe 14 is connected to the suction port of the stirring pump 28.
Further, the pump discharge pipe 11 is connected to the discharge port of the stirring pump 28, and the valve 29 is arranged in the pump discharge pipe 11.

The stirring pump 28 is driven by the pump motor 28A. The stirring pump 28, the pump suction pipe 15, and the pump discharge pipe 11 constitute a stirring pump device 30.

The transfer pipe 16 connected to the communication pipe 14 is connected to the suction port of the transfer pump 31. A regeneration device 33 is connected to the discharge port of the transfer pump 31 via a regeneration pipe 32. By this regenerator 33, the radioactive waste liquid in the storage device 3 is subjected to chemical treatment such as filtration and desalting. In addition, a valve 34 is installed in the regeneration pipe 32.
Is installed. The transfer pump 31 is driven by a pump motor 31A.

Next, the operation will be described.

A radioactive waste liquid such as device drain water discharged from various devices installed in the nuclear power generation facility is guided to and stored in the storage container 3 of the waste liquid storage device 1. When the radioactive waste liquid is stored, minute solids such as ion exchange resin and clad are deposited and deposited on the bottom of the storage container 3. When a predetermined amount of radioactive waste liquid is stored in the storage container 3, the waste liquid is transferred to the regenerator 33 for chemical treatment such as filtration and desalting. However, when the sediment is deposited on the bottom of the storage container 3, the radioactive waste liquid cannot be directly transferred to the regenerator 33. In this case, therefore, the transfer pump 31 is stopped and the valve 34 is closed. Then, the stirring pump 28 is started. At this time, the valve 29 is also kept open.

When the stirring pump 28 is started, the supernatant waste liquid (mother liquor) of the radioactive waste liquid stored in the storage container 3 passes from the suction guide element 21 of the waste liquid storage device 1 through the inside pipe 8, and the communication pipe 14 and the pump suction pipe. It is sucked into the stirring pump 28 via 15. This supernatant waste liquid is pressurized by the agitation pump 28, and is discharged to the spherical portion 9 of the outer pipe 7 through the pump discharge pipe 11. The flow of the supernatant liquid waste discharged into the spherical portion 9 is converted into a substantially right angle, rises through the annular flow path 12, is guided by the radial guide vanes 18 of the injection guide element 17, and the flow direction is changed. It is converted to a substantially right angle again. Then, the supernatant waste liquid is radially ejected from the entire circumference of the annular ejection port 20 of the ejection guide element 17 so as to crawl on the bottom surface of the storage container 3.

The supernatant waste liquid jetted from the annular jet port 20 flows along the bottom surface of the storage container 3 to stir the precipitate and stir it to mix it. This jet flow induces an entrained flow 35 that is several times the pump discharge flow rate. These jets and accompanying flows
35 flows in the radial direction and reaches the side wall surface of the storage container 3, and rises as a huge upward flow from this side wall surface, so that an annular flow occurs in a torus shape in the entire inside of the storage container 3,
The precipitate can be effectively and efficiently stirred and mixed throughout the container.

When the stirring of the precipitate is completed in the storage container 3 and the radioactive waste liquid is uniformly stirred and mixed, the transfer pump 31 is started,
Open valve 34. When the transfer pump 31 is activated, the radioactive waste liquid in the storage container 3 is pressurized by the transfer pump 31 through the suction guide element 21, the inner pipe 8, the connecting pipe 14 and the transfer pipe 16. The pressurized radioactive waste liquid is sent to the regenerator 33 through the regenerator pipe 32, where it is chemically treated. The operation of the stirring pump 28 may be stopped when the transfer pump 31 is started, but it is more efficient to keep the operation of the stirring pump 28 by opening the valve 29.

By the way, when the inside of the storage container 3 is inspected, it is necessary to completely discharge the radioactive waste liquid stored in the storage container 3. At this time, if the radioactive waste liquid is retained in the annular flow path 12 of the outer pipe 7, it becomes impossible to completely discharge the radioactive waste liquid. However, in the first embodiment, the annular flow path 12
Since the radioactive waste liquid inside can be flowed to the branch port 13 side of the outer pipe 17 from the gap 27 between the lower end portion 26 of the inner pipe 8 and the spherical portion 9 of the outer pipe 7, the radioactive waste liquid inside the storage container 3 can be completely discharged. Can be discharged. The flow of the radioactive waste liquid through the gap 27 also occurs during the normal stirring operation, but if the gap size is set appropriately from the capacity of the stirring pump 28, the actual reduction in stirring efficiency can be ignored.

Further, in this first embodiment, by loosening the mounting bolt 19, the entire inner tube 8 and the injection guide element 17 including related accessories such as the suction guide element 21 can be disassembled from the storage container 3, so that the inner tube 8 Also, it is possible to inspect and repair the corrosion and wear occurring in the liquid contact part of the double pipe part composed of the outer pipe 7. Further, since the suction guide element 21 can be easily disassembled by removing the mounting bolt 22, the inner surface of the inner pipe 8, the suction guide element 21 and the injection guide element 17 can be easily inspected and
Can be repaired. At the same time, if necessary, suction guide element
It is also possible to replace 21 or the integrated inner tube 8 and injection guide element 17.

In addition, in the double pipe portion of the outer pipe 7 and the inner pipe 8, that is, in the annular flow path 12 that redirects the liquid flow at a substantially right angle,
Since the spherical portion 9 which is one step larger than the other portion of the outer pipe 7 is provided below the outer tube 7, the flow velocity is reduced in the spherical portion 9 and the disturbance of the streamline can be prevented. As a result, it is possible to reduce the pressure loss in the double pipe portion and suppress the generation of harmful vibration and cavitation corrosion caused by the vortex flow.

Further, since the suction guide element 21 is mounted on the upper end of the inner pipe 8 and the suction port 24 is opened over the entire circumference in the horizontal direction, the radioactive waste liquid can be dispersed and sucked from the entire circumference in the horizontal direction. Therefore, even if the liquid level of the radioactive waste liquid in the storage container 3 is lowered, air is not sucked into the inner pipe 8 by the suction vortex flow, and the pump performance and life of the stirring pump 28 are not adversely affected. . Therefore, the stirring stop liquid level in the storage container 3 can be set to a level as low as the vicinity of the upper end of the suction guide element 21. (Effective capacity) can be increased.

Further, since the small hole 25 is formed in the upper part of the suction guide element 21, even if the radioactive waste liquid remains outside the upper part of the suction guide element 21, this waste liquid can be guided into the suction guide element 21 through the small hole 25. At the time of internal inspection, all radioactive waste liquid stored in the storage container 3 can be completely discharged.

Further, this small hole 25, during normal operation of the stirring pump device 30, when the radioactive waste liquid is concentrated from the entire circumference of the suction port 24 of the suction guide element 21 in the horizontal direction, a vortex flow generated near the center of the inside of the suction guide element 21. Effective for crushing.

Further, since the lower end portion 26 of the inner pipe 8 is enlarged and formed in a truncated hollow conical shape, the internal pressure generated in the annular flow passage 12 of the double pipe portion is applied to the mounting bolt 19 of the injection guide element 17. The acting tensile force of the inner tube 8 is canceled (balance piston effect). Therefore, since the tensile force acting on the mounting bolts 19 can be reduced, the number of the mounting bolts 19 can be reduced and the assembling property of the inner pipe 8 can be improved. Further, since the lower end portion of the inner pipe 8 has a truncated hollow conical shape, the inner pipe 8 can be easily inserted into the outer pipe 7 and the streamline in the lower portion of the spherical portion 9 of the outer pipe 7 can be reduced. Disturbance can also be reduced.

Furthermore, the inner pipe 8 may be changed depending on the driving conditions and the surrounding atmosphere.
However, since the inner tube 8 can freely expand and contract in the axial direction, thermal stress does not occur in the inner tube 8 and the outer tube 7.

Further, since the stirring pump 28 is provided on the floor 6 of the storage chamber 4 and is not installed in the storage container 3, the stirring pump 28 can be easily maintained and inspected, and no special pump specifications are required. Therefore, the pump pressure can be increased and the pump can be downsized. Further, since electric equipment such as a motor is not disposed in the radioactive waste liquid, it is possible to effectively prevent an electric shock accident of a worker and at the same time prevent electrical corrosion of the storage container 3.

Further, since the stirring pump 28, the pump motor 28A, etc. are fixed to the floor surface 6 of the storage chamber 4, the seismic resistance and radiation resistance of the constituent materials of the waste liquid storage device 1 can be improved, and radioactive waste liquid with strong radioactivity However, it can be safely stirred.

FIG. 3 is an enlarged cross-sectional view of an essential part showing a modified example of the first embodiment. In this modification, the same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In this modification, the lower end of the inner pipe 8 is not enlarged, but is fitted into the lower part of the spherical portion 9 of the outer pipe 7. According to this modification, the internal pressure generated in the annular flow passage 12 does not act on the inner pipe 8, and the so-called balance piston effect is not exhibited. Therefore, the tensile force acting on the mounting bolt 19 becomes large, but if the tensile strength of the mounting bolt 19 is designed in consideration of it in advance, it can be put to practical use sufficiently.

FIG. 4 is an enlarged partial sectional view of an essential part showing a second embodiment of the waste liquid storage device according to the present invention. Also in the second embodiment, the same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the waste liquid storage device of the second embodiment, the suction / injection guide element in which the suction guide element and the injection guide element are integrated
41 is fixed to the center of the bottom of the storage container 3 by a mounting bolt 43. A small hole 25 is also formed in the upper portion of the suction / injection guide element 41. The outer pipe 44 has upper and lower flanges, and the upper flange 45 is bolted to the storage container 3. Further, a horizontal branch port 46 is provided near the center of the outer pipe 44 in the longitudinal direction.
Is arranged and connected to the pump discharge pipe 11 via a reducer 47 having a large diameter.

The inner pipe 48 is inserted into the outer pipe 44 from the outside of the storage container 3, and the upper end is fitted into the inner diameter portion of the suction / injection guide element 42. In addition, the lower end flange 49 of the inner pipe 48 is
It is fixed by bolting to the lower flange 50 of 44. A connection pipe 51 is bolted to a lower end flange 49 of the inner pipe 48, and the connection pipe 51 is connected to the pump suction pipe 15 and the transfer pipe.
16 connected to each.

According to the second embodiment, the inner pipe 48 can be disassembled to the outside of the storage container 3, so that an operator does not enter the storage container 3 to inspect and repair the inner and outer surfaces of the inner pipe 48 and the outer pipe 44. The radiation exposure of workers can be reduced. In addition, also in the second embodiment, the same effect as that of the first embodiment is obtained.

FIG. 5 and FIG. 6 are enlarged partial cross-sectional views of the essential parts showing a first modified example and a second modified example of the second embodiment, respectively.
In these modified examples, the same parts as those in the second embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the first modification shown in FIG. 5, the outer pipe 52 and the inner pipe 53 are curved so that the lower flange 50 and the lower end flange 49 are both horizontal, and the vertical dimension of the double pipe portion is reduced. It is a thing. Although disassembling the inner pipe 53 is expected to be somewhat difficult, it can be disassembled to the curved connecting pipe 54 side. As a result, the height of the support skirt 5 can be reduced, and the height of the entire waste liquid storage device can be reduced. The downsizing of the waste liquid storage device improves the seismic strength, and since the entire device can be downsized, the entire building of the nuclear power generation facility can be downsized.

In the outer pipe 52, a horizontal reducer 55 is integrally molded between the upper flange 45 and the lower flange 50, and the pump discharge pipe 11 is connected to the horizontal reducer 55 by bolting.

In the second modification shown in FIG. 6, the suction / injection guide element 56
The shape of the suction portion is a pipe shape having a T-shaped cross section. In this second modification, another suction / injection guide element 41
Although the suction performance is slightly reduced as compared with the above, it can be sufficiently put into practical use if this is taken into consideration.

In addition, in each of the above-described embodiments and modifications, the storage container 3
I described the case of a cylindrical freestanding tank whose bottom surface is spherical,
The same effect can be achieved even with a lining container in which a metal lining plate is lined inside a concrete skeleton.

Further, although each of the embodiments and each of the modified examples is the case of the nuclear power generation facility, the present invention is not limited to the nuclear power generation facility, and is not limited to the power generation and is not related to other nuclear power-related facilities or nuclear power or radioactivity. Generally applicable to facilities.

〔The invention's effect〕

As described above, according to the present invention, inside the outer pipe that guides the pump pressurizing liquid from the stirring pump to the injection guide element,
The inner pipe that guides the waste liquid in the storage container to the agitation pump side is housed to form a double pipe structure, and the inner pipe is detachably housed in the outer pipe, so the inner pipe is removed during maintenance and inspection of the device. Since the corrosion and wear of the wetted part of the double pipe can be easily inspected and repaired, and the inner pipe can be easily replaced if necessary, maintenance and inspection of the device can be efficiently performed.

Further, since the large diameter portion is formed at the lower end portion of the inner pipe, the pressure of the pump pressurizing liquid is applied to the large diameter portion, and a force for urging the inner pipe downward is generated. Therefore, the force for fixing the inner pipe to the bottom of the storage container can be reduced, and the assembling property of the inner pipe can be improved. Since the lower end of the inner pipe is inserted and connected to the outer pipe, the inner pipe can freely expand and contract in the axial direction even if a temperature difference occurs between the inner pipe and the outer pipe due to changes in operating conditions and the surrounding atmosphere. Therefore, thermal stress is not generated in the inner pipe and the lower pipe.

Further, since the small hole for communicating the inside and the outside is provided at the center of the upper part of the suction guide element, when discharging the waste liquid, the waste liquid is not left on the upper part of the suction guide element. As a result, it is possible to reduce the radiation exposure dose during operations such as replacement or inspection of the inner tube. Further, since the size of the vortex generated on the surface of the waste liquid by suction from the suction guide element can be reduced, troubles such as vibration of the transfer pump due to air inclusion can be prevented.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part of FIG. 2, FIG. 2 is an entire sectional view showing a first embodiment of a waste liquid storage device according to the present invention, and FIG.
FIG. 4 is an enlarged sectional view of an essential part showing a modified example of the first embodiment of FIG. 1, FIG. 4 is an enlarged partial sectional view of an essential part showing a second embodiment of the waste liquid storage device according to the present invention, FIG. FIG. 6 is an enlarged partial sectional view of an essential part showing a first modification and a second modification of the second embodiment. 1 ... Waste liquid storage device, 3 ... Storage container, 7 ... Outer pipe,
8 ... Inner pipe, 11 ... Pump discharge pipe, 12 ... Annular flow passage, 15 ... Pump suction pipe, 17 ... Injection guide element, 20
...... Spout, 21 …… Suction guide element, 24 …… Suction port, 28
…… Agitation pump.

Claims (1)

[Claims] 1. A storage container for storing a waste liquid such as radioactive waste liquid, an injection guide element provided at the bottom of the storage container and having an annular jet outlet, and a pump discharge provided outside the storage container. A stirring pump having a pipe and a pump suction pipe connected thereto, the waste liquid in the storage container is sucked by the operation of the stirring pump, and the pump pressurizing liquid is pumped from the annular ejection port of the injection guide element to the bottom surface of the storage container. In a waste liquid storage device configured to radially inject along, a pump liquid is provided at the bottom of the storage container and connected to the pump discharge pipe, and the pump pressurized liquid in the pump discharge pipe is supplied to the injection guide element. An outer pipe for guiding and an inner pipe that is detachably accommodated in the outer pipe and is connected to the pump suction pipe to guide the waste liquid stored in the storage container to the pump suction pipe. The inner pipe is provided with a suction guide element for restricting the inflow of waste liquid from directly above and guiding the waste liquid from a substantially lateral direction at the upper end of the inner pipe, and a large diameter portion is formed at the lower end of the inner pipe. Is inserted and connected to the outer tube,
A waste liquid storage device, characterized in that a small hole for communicating the inside and the outside is provided in the upper center of the suction guide element.