JPH0527091A - Radioactive waste solidifying device - Google Patents

Abstract

PURPOSE:To obtain a radioactive waste solidifying device which maintains the toughness of a mixing mechanism and reduces the radioactive ray exposure to operators by washing and removing the radioactive waste adhering on mixing blades by revolving the mixing blades and spraying the kneading water onto the mixing blades. CONSTITUTION:A radioactive waste solidifying device is equipped with storage containers 40 and 40a for accommodating and solidifying the radioactive waste, solidifying agent, and kneading water and mixing blades 52 for agitating the mixture, and further equipped with an elevator device 60 for separating and assembling the mixing blades and the storage container, transfer device 70 for transferring-in/out the storage container, vibrating mechanism for applying vibration on the mixing blades, and a kneading water injection nozzle 31 for jetting the kneading water onto the mixing blades.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radioactive waste solidifying device for solidifying radioactive waste generated from radioactive material handling facilities such as nuclear power plants and reprocessing facilities.

[0002]

2. Description of the Related Art Conventionally, hydraulic cement such as Portland cement or blast furnace cement has been used for solidification of radioactive waste such as concentrated waste liquid or used ion exchange resin generated from radioactive material handling facilities. Came.
The devices for solidifying these wastes with cement were roughly classified into two types.

That is, radioactive waste and cement are mixed in a dedicated mixing tank, and the resulting mixed kneaded material is transferred into a container for solidifying radioactive waste and hardened into an outdrum mixing method (Outdram mixing method). Mixing Meth
od) and radioactive waste and cement are mixed directly in a container for solidification of radioactive waste and cured to form a solidified product. Indrum mixing method (Indram Mixing M)
method).

[0004]

In the outdrum mixing method, when the radioactive waste and the hydraulic cement are mixed and discharged from the mixing tank, the cement kneaded material remains on the wall surface of the mixing tank or the mixing blade. This is the source of radiation exposure. Further, if the kneaded material adheres to the mixing blade, the performance of the mixing blade may be deteriorated. For this reason, it was necessary to fill the mixing tank with water and rotate the mixing blades for cleaning. At this time, a large amount of radioactive cleaning waste liquid is generated, so
A treatment device for these waste liquids must be additionally installed.

Even in the in-drum mixing method, the cement mixture remains on the mixing blades after the mixing is completed.
A container is required to collect radioactive cleaning waste liquid generated when these are washed off. Further, an apparatus for treating the radioactive cleaning waste liquid is required. In either case, there was a problem that the device was upsized and maintenance was difficult.

The object of the present invention is to maintain the soundness of the mixing mechanism by rotating the radioactive kneaded material adhering to the mixing blade while vibrating the mixing blade and spraying the kneading water onto the mixing blade to wash it off. , To reduce the radiation exposure of employees.

Further, the radioactive cleaning liquid used for cleaning the mixing blades is stored in a storage container and utilized for solidification of the next batch, so that secondary radioactive waste is eliminated as much as possible.

[0008]

In order to achieve the above object, in the present invention, a waste material supply mechanism, a solidifying material supply mechanism, a kneading water injection mechanism, the waste material supply mechanism and a solidifying material supply mechanism. And a first storage container for storing the radioactive waste, the solidifying material, and the kneading water supplied from the kneading water injection mechanism, and the mixing for kneading the radioactive waste, the solidifying material, and the kneading water in the first storage container. A blade, a vibrating mechanism for vibrating the mixing blade, a kneading water injection nozzle for spraying kneading water to the mixing blade, a mixing blade and a first storage container separated from each other, and a second storage container combined. There is provided an apparatus for solidifying radioactive waste, comprising: an elevating device for carrying out the first storage container and a transfer device for carrying out the second storage container.

[0009]

With this structure, the radioactive waste contained in the first storage container, the solidifying material and the kneading water are stirred by the mixing blade. After the kneading is completed, the storage container and the mixing blade are separated. While vibrating the mixing blade with the vibrating mechanism, the mixing blade is rotated in the second storage container to efficiently separate the kneaded material adhering to the mixing blade. Further, even if a small amount of kneading water is sprayed from the kneading water injection nozzle toward the mixing blade, the radioactive kneaded material adhering to the mixing blade can be washed off. Therefore, the soundness of the mixing blade can be maintained and the radiation exposure can be reduced. It is also possible to eliminate the radioactive secondary waste by containing the radioactive cleaning liquid in the second storage container and utilizing it for the solidification of the next batch.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, a waste supply mechanism 10 for supplying radioactive waste is installed above a first storage container 40 that is lifted to a fixed position in the upper part. Similarly, in order to solidify this radioactive waste, a solidifying material supply mechanism 20 for supplying a solidifying material is also provided above the storage container 40. Further, a kneading water injection mechanism 30 for supplying kneading water for kneading the radioactive waste and the solidifying material is also provided above the storage container 40.

In the storage container 40, a mixing blade 51 is inserted to stir and knead the radioactive waste, the solidifying material and the kneading water. A mixing mechanism 50 for rotating the mixing blade 51 is fixed above the storage container 40. After the mixing of the radioactive waste, the solidifying material and the kneading water, the first storage container 40 containing the kneaded material and the mixing blade 51 are separated from the elevating device 60.

By using this elevating device 60, the mixing vane 51 has a second storage container 40a containing no kneaded material.
Can also be incorporated. By moving the mixing mechanism 50 up and down, the storage containers 40 and 40a and the mixing blade 51 can be separated and assembled. A transfer device 70 for carrying out the separated first storage container 40 or carrying in the second storage container 40a is installed adjacent to the elevating device 60.

After the separation, a vibrating mechanism 80 for vibrating the mixing blade 51 is attached to an intermediate portion of the mixing mechanism 50 in order to efficiently separate the kneaded material adhering to the mixing blade.

In order to remove the kneaded material remaining on the mixing blade 51, a kneading water injection nozzle 31 capable of spraying the kneading water toward the mixing blade 51 is installed above the storage containers 40, 40a. ..

The storage containers 40 and 40a are fixed on a support base 61 of the lifting device 60 by fixing pawls 62. The support mechanism 61 is moved up and down by the up-and-down mechanism 63 to move the storage containers 40 and 40a up and down.

The lifting device 60 is loaded on a carriage 71 of the transfer device 70. By the moving mechanism 72, the carriage 71
By moving the
That is, the storage containers 40, 40a can be transferred in the left-right direction. A specific configuration of the radioactive waste solidification device will be described with reference to FIG.

An electric motor 11, which is a drive source of the waste supply mechanism 10, is installed on a gantry 12. The rotation of the electric motor 11 is transmitted to the screw feeder 13. At this time, the radioactive waste 14 is taken in through the supply port 15, discharged through the discharge port 16 through the screw feeder 13, and stored in the storage container 40.

The solidifying material supply mechanism 20 has the same structure as the waste material supply mechanism 10. An electric motor 21 as a drive source is attached to the gantry 12, and the rotation of the electric motor 21 is transmitted to the screw feeder 22. At this time, the solidified material 23 is taken in through the supply port 24 and discharged through the discharge port 25 through the screw feeder 22.
It is housed in 0.

The solidifying material 23 is a hydraulic inorganic solidifying material, which is a commonly used cement or the one in which an aggregate and an additive are added to it, or a non-cement inorganic such as water glass. It targets all that starts the curing reaction by mixing water or kneading water containing water as a main component with the inorganic solidifying material.

Through the injection pipe 32 of the kneading water injection mechanism 30, kneading water 33 containing water as a main component flows. A valve 34 is interposed in the middle of the injection pipe 32 to control the flow rate of the kneading water 33. An injection ring 35 is provided at the end of the injection pipe 32.
Is installed.

The storage containers 40, 40a are not limited in material or shape, such as a commonly used drum or a drum whose inner side is coated with an inorganic material or an organic material. Mixing blade 51 of mixing mechanism 50
Is inserted into the storage container 40, and the radioactive waste 13
It is used for stirring the solidifying material 23 and the kneading water 33. The shaft rotation of the electric motor 52 is transmitted to the speed reducer 53, is rotatably supported by the bearing 55 at the intermediate portion via the rotation shaft 54, and is transmitted to the mixing blade 51.

An electric motor 81, which serves as a drive source for the vibration of the vibrating mechanism 80, is installed on the frame 12. The rotation of the electric motor 81 is transmitted to the vibrator 82. The vibration exciter 82 causes vibration by an eccentric cam (not shown). This vibration is transmitted to the vibration shaft 83. The vibration of the vibrating shaft 83 is transmitted to the rotating shaft 54 via a bearing 84 for freely transmitting the rotation. Further, a flexible coupling 85 is interposed in the middle of the rotary shaft 54 so that the rotary shaft 54 can be easily vibrated.

As shown in FIG. 3, the injection ring 35 of the kneading water injection mechanism 30 has such an outer diameter that it can be inserted into the storage containers 40, 40a. On the lower surface of the injection ring 35, a plurality of kneading water injection nozzles 31 are provided. The kneading water 33 from the kneading water injection nozzle 31 is sprayed on the mixing blade 51.

As shown in FIGS. 2 and 4, the mixing blades 51 of the mixing mechanism 50 are attached to the rotary shaft 54 through attachment rings 56 over several stages in the vertical direction. When the mixing blade 51 is viewed from below, a plurality of blades 57 are fixed to the attachment ring 56, and the cross section of the blade 57 has a triangular shape for easy kneading. The operation of this embodiment will be described.

The solidification material supply mechanism 20 supplies the hydraulic inorganic solidification material 23 and the kneading water 33 composed of water and a moderator into the first storage container 40 by the kneading water injection mechanism 30.
After that, the mixing blade 51 of the mixing mechanism 50 is rotated to sufficiently knead. The radioactive waste 14 is supplied by the waste supply mechanism 10, and similarly, the mixing blade 51 is rotated to sufficiently knead,
Make a uniform kneaded product.

After the kneading is completed, the first storage container 40 loaded on the support base 61 of the lifting device 60 is pushed down to separate the storage container 40 and the mixing blade 51 of the mixing mechanism 50. At the time of this separation, the vibrating mechanism 80 causes the mixing blade 51 to rotate while vibrating. When minute vibration is continuously applied to cement that has not solidified after the completion of kneading, it has much higher fluidity than cement that is not vibrated. Therefore, the kneaded material attached to the mixing blade easily flows down due to vibration.

The first storage container 40 containing the kneaded material is carried out by the transfer device 70, and the second storage container 40 containing the kneaded material is removed.
The storage container 40a is loaded. After assembling the second storage container 40a in the mixing blade 51 by the elevating device 60, the second blade is rotated while the mixing blade 51 is vibrated. Further, the kneading water injection nozzle 3 of the kneading water injection mechanism 30 is attached to the mixing blade 51.
The kneading water is sprayed from No. 1, and the radioactive kneaded material remaining on the mixing blade 51 is caused to flow down. The mixing blades 51 may be sprayed with the kneading water after the mixing process in each of the storage containers 40 and 40a, or at the time when the solidification process is performed a plurality of times.

Further, the cleaning waste liquid consisting of the kneading water used for cleaning the mixing blade 51 is stored in the second storage container and utilized for the solidification of the next batch to eliminate the radioactive secondary waste. be able to. Next, the results of the cleaning test conducted using a 200 liter drum (JIS1600) will be described. Case 1

The waste, cement and kneading water shown in Table 1 were mixed. A required amount of kneading water was put in a 200-liter drum and cement was added while rotating the mixing blade to prepare a cement slurry. The dry powder of concentrated waste liquid was added to this and mixed. After the mixing was completed, the drum was replaced, and the vibration mechanism attached to the mixing mechanism applied a vibration frequency of 1000 Hz and an amplitude of 2 mm while rotating the mixing blade. At this point the cement slurry had run down. next,
The kneading water was sprayed toward the mixing blade. This kneading water and the vibration of the blade caused the waste remaining on the mixing blade to flow down. As a result of surface contamination detection by surface smear, no cement component was observed.

[0031]

[Table 1] Case 2

Waste, cement and kneading water shown in Table 2 were mixed. Put the required amount of kneading water in a 200-liter drum, add the cement while rotating the mixing blade,
Made a cement slurry. The used powder ion-exchange resin was added to this and mixed. After the mixing was completed, the drum was replaced, and the vibration mechanism attached to the mixing mechanism applied a vibration frequency of 1000 Hz and an amplitude of 2 mm while rotating the mixing blade. At this point the cement slurry had run down. The kneading water was sprayed toward the mixing blade. This kneading water and the vibration of the mixing blade caused the waste material remaining on the mixing blade to flow down. As a result of surface contamination detection by surface smear, no cement component was observed.

[0033]

[Table 2] Case 3

Waste, cement and kneading water shown in Table 3 were mixed. A required amount of kneading water was put in a 200-liter drum and cement was added while rotating the mixing blade to prepare a cement slurry. To this, dry powder of sodium nitrate was added and mixed. After the mixing was completed, the drum was replaced, and the vibration mechanism attached to the mixing mechanism applied a vibration frequency of 1000 Hz and an amplitude of 2 mm while rotating the mixing blade. At this point the cement slurry had run down. next,
The kneading water was sprayed toward the mixing blade. By the vibration of the kneading water and the mixing blade, the waste remaining on the mixing blade was flown off. As a result of surface contamination detection by surface smear, no cement component was observed.

[0035]

[Table 3]

As described above, according to the present embodiment, the mixing blade is vibrated while being vibrated, and the mixing blade is sprayed with the kneading water to wash it off, thereby maintaining the soundness of the mixing blade and exposing the worker. Reduction can be achieved.

[0037]

As described above, according to the present invention,
It is possible to maintain the soundness of the mixing mechanism and reduce the radiation exposure of employees.

[Brief description of drawings]

FIG. 1 is a side view of the entire radioactive waste solidification device according to the present invention.

FIG. 2 is a specific configuration diagram showing an embodiment of the present invention.

FIG. 3 is a configuration diagram showing a lower surface of an injection ring in the kneading water injection device of FIG.

FIG. 4 is a configuration diagram showing a lower surface of the mixing blade of FIG.

[Explanation of symbols]

10 ... Waste supply mechanism 20 ... Solidification material supply mechanism 30 ... Kneading water supply mechanism 31 ... Kneading water injection nozzle 40 ... First storage container 40a ... Second storage container 50 ... Mixing mechanism 51 ... Mixing blade 60 ... Elevating device 70 ... Transfer device
80 ... Excitation mechanism

Claims (1)

Claims: 1. A waste supply mechanism, a solidifying material supply mechanism,
Kneading water injection mechanism, first storage container for storing radioactive waste, solidification material and kneading water respectively supplied from the waste supply mechanism, solidification material supply mechanism and kneading water injection mechanism, and the first storage A mixing blade for kneading the radioactive waste in the container, the solidifying material and the kneading water, a vibrating mechanism for vibrating the mixing blade, a kneading water injection nozzle for spraying the kneading water on the mixing blade, and the mixing blade. The first storage container is separated into the second
A solidification device for radioactive waste, comprising: an elevating device for assembling the storage containers of 1. and a transfer device for carrying out the first storage container and carrying in the second storage container.