JPH0750194B2 - Method for solidifying radioactive waste and rolling machine for solidifying radioactive waste - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention uses a radioactive waste solidification treatment method for solidifying pellet-like or powdery radioactive waste in a solidification container, and directly uses it for carrying out the method. Regarding the rolling machine.

[Conventional technology]

Conventionally, the following methods have been proposed as a method for solidifying radioactive waste.

(1) As a method of solidifying liquid waste, there is a method of using cement as a solidifying material. This is a method in which a solidification container is filled with a predetermined amount of radioactive waste liquid, and then, while a predetermined amount of cement is being added, the mixture is stirred by a stirring blade in the solidification container to form a cement paste, which is solidified in the solidification container. is there. A method of kneading and solidifying in a solidifying container in this manner is called an in-drum solidifying method. On the other hand, there is also a method in which the radioactive waste liquid and cement are kneaded in a kneading tank and the kneaded paste is filled in a solidification container, which is called an outdrum solidification method.

(2) As a method for solidifying radioactive waste after pulverizing it, there is a plastic solidification method (Japanese Patent Laid-Open No. 53-40).
No. 199). This method is a method in which liquid radioactive waste is dried and powdered by a dryer, and then the waste powder and plastic as a solidifying material are kneaded in a kneading tank and filled in a solidification container and solidified. Is.

(3) There is a method in which the waste is made into a dry powder, then formed into pellets, and the pellets are solidified (JP-A-52).
-85699). In this method, after the pellets are filled in the solidification container, a paste-like solidification material prepared by kneading in advance by a solidification material tank is injected from the upper part to fill the space between the pellets and fix the pellets in the solidification container.

[Problems to be solved by the invention]

In the solidification treatment method of kneading the waste and the solidifying material in the kneading tank as described above, since the kneading tank is contaminated with the waste, periodic decontamination or cleaning is required, and in the solidification container Even with the method of kneading with a stirring blade, periodical decontamination or cleaning of the stirring blade is necessary. In these cases, decontamination /
Along with the generation of secondary waste due to cleaning, decontamination / cleaning equipment and secondary waste treatment equipment are required, and the treatment equipment becomes large-scale.

Further, in the method of solidifying the pellet-shaped waste as described above, there is no difference in that a kneading tank of the solidifying material is required, and when burr or powder is partially mixed, Just by injecting the solidifying material from the upper portion of the filled solidifying container, the solidifying material does not flow down to the lower portion of the solidifying container, and it is difficult to integrate the waste in the solidifying container.

In addition, it is necessary to select and develop a solidified material with low viscosity.

[Means for solving problems]

The method for treating radioactive waste according to the present invention is a method in which pelletized or powdered radioactive waste and a paste-like solidifying material prepared by kneading in advance by a solidifying material tank are put into a solidification container and hermetically sealed. A motive force is used to cause the solidification container to perform a two-degree-of-freedom rotary motion of a rotary motion about its own axis and a rotary motion about an orbital axis, whereby the radioactive waste and the solidifying material in the solidification container are separated. It is characterized in that it is kneaded uniformly and then solidified in the solidification container.

In addition, the rolling machine directly used for carrying out the above-mentioned treatment method according to the present invention, the radioactive waste in the form of pellets or powder and the paste-like solidifying material pre-kneaded by the solidifying material tank are charged and sealed. A pair of holders for removably sandwiching the solidification container, an arm or a frame that rotatably supports the holder and that is rotatably supported around a revolution axis intersecting with the rotation axis of the holder, The solidification container is composed of a drive means for rotating the holder around the rotation axis and a drive means for rotating the arm or frame around the revolution axis, and rotating the solidification container in two degrees of freedom. It is characterized in that the radioactive waste therein and the solidifying material are uniformly kneaded.

[Action]

The waste and the solidifying material filled in the solidification container are uniformly kneaded by rolling the entire solidification container so that the solidification container acts as one kneading tank. It is recommended that the rolling shaft should be placed in all directions in the up / down and left / right directions. After the kneading by rolling of the solidification container, the kneaded product of the radioactive waste and the solidifying material in the solidification container is solidified in the solidification container as it is.

〔Example〕

FIG. 1 is a system flow chart showing an embodiment of the present invention. Radioactive waste is put into the solidification container 2 from the waste tank 1. The waste may be in the form of pellets or powder. The solidification container 2 into which the waste is put is stored immediately or as needed in the waste storage 5 to measure radioactivity attenuation, and then is kneaded in advance in the solidification material tank 3 to solidify the paste-like solidification material. Then, the whole solidification container 2 is tumbled by a rolling machine 4 to be kneaded and solidified in the solidification container 2.

FIG. 2 shows the overall system flow of an embodiment in which waste is solidified in powder form. The liquid radioactive waste is supplied from the waste supply tank 6 to the dryer 7 and pulverized. As the dryer 7, a centrifugal thin film type dryer or a calcining furnace can be used. The dry powdered waste is filled in the solidification container 2 via the waste hopper 1 '. Next, a paste-like solidifying material prepared by kneading in advance by the solidifying material tank 3 is put into the solidifying container 2, and the rolling machine 4
Thus, the solidification container 2 is tumbled to knead the waste and the solidifying material and solidify in the solidification container 2.

FIG. 3 shows the overall system flow of an embodiment in which waste is solidified in pellet form. The liquid waste is supplied from the waste supply tank 6 to the dryer 7 and pulverized,
Then, it is pelletized by the granulator 9. The waste pellets are filled in the solidification container 2 via the waste hopper 1 '. The subsequent steps are the same as described above.

FIG. 4 and FIG. 5 show the schematic internal structure of the solidification container 2. The figure (a) shows a plan view and the figure (b) shows a side view, respectively. The solidification container 2 has a kneading blade 10 inside to improve the kneading property during rolling. Further, by filling ceramic balls or steel balls in the solidification container 2, the internal kneading property is improved. At the time of kneading, the waste and the solidifying material are sealed in a solidifying container with a lid.
In addition, it is preferable that a treatment for preventing scattering is performed by a vent system.

FIG. 6 shows an example of the solidification container 2 and a rolling machine 4 that rolls and rotates to solidify. In FIG. 6, the solidification container 2 is supported by a holder 15 and is pressed by a hydraulic cylinder 11.
It is clamped in a stable state via 12 and thereby held by the rotating arm 4 ′ of the rolling machine 4. When removing,
Lower the hydraulic cylinder 11 to remove the applied pressure, and
Remove more.

The solidification container 2 held by the rolling machine 4 is rotated at a predetermined rotation speed by the rotation motor 14, and the entire solidification container 2 is further rotated around the revolution shaft 16 together with the arm 4 '. The solidification container 2 is tumbled by such a two-degree-of-freedom rotary motion, and the waste in the solidification container 2 and the solidification material are kneaded.

FIG. 7 shows another embodiment which facilitates setting and removal of the solidification container on the rolling unit 4. The solidification container 2 is hung by a hook 18 and set on the rolling machine 4 by a hoist 17. The arm 4'of the rolling machine 4 is composed of two parts, and the upper half thereof is inverted as shown in FIG. Then, return the upper half of the inverted arm 4'as shown in FIG.
The solidification container 2 is held and fixed by the hydraulic cylinder 11 at a predetermined pressure via a pressure spring.

FIG. 8 shows another example of the rolling machine. In this apparatus, the solidification container 2 is set by a holder 15 between holding frames 19 forming a square frame, and is fixed and held by a hydraulic cylinder 11 via a pressure spring 12. The solidification container 2 is rotated (rotated) by a rotation motor 14 and is revolved around a revolution shaft 16. Such a solidification container 2 is rolled by two-degree-of-freedom rotary motion of rotation and revolution, and the waste and solidification material in the solidification container 2 are kneaded and solidified.

〔The invention's effect〕

 According to the present invention, the following effects can be expected.

(1) The pellet-like or powder-like radioactive waste is kneaded in the solidifying container with the paste-like solidifying material which is previously kneaded in the solidifying material tank, and then solidified in the solidifying container as it is. , A separate kneading tank is unnecessary, the equipment constituting the equipment can be simplified, and the economical efficiency is improved.

(2) Since the kneading tank is no longer needed, radioactive secondary waste such as cleaning waste liquid of the kneading tank and its stirring blades will not be generated, and the facility for treating the secondary waste will be unnecessary.

(3) Even if the waste is in the form of pellets or powder, it is possible to treat the solidified product uniformly.

(4) By using a rolling machine capable of rotational movement with two degrees of freedom, the solidification container undergoes two degrees of freedom rotational movement around its own axis and rotational movement about the revolution axis to knead and knead. Even if a high paste-like solidifying material is used, the kneading can be effectively performed in a short time.

[Brief description of drawings]

1, 2 and 3 are overall system flow charts of an embodiment of the present invention, and FIGS. 4 (a) and 4 (b) are plan views and side views of a solidification container suitable for use in the present invention. FIGS. 5 (a) and 5 (b) are plan views and side views of another solidification container, FIG. 6 is a side view of a rolling machine, and FIGS. 7 (a) and 7 (b).
Is a side view showing a state of another embodiment of the rolling machine, and FIG. 8 is a side view showing another embodiment of the rolling machine. 1,1 '…… Waste hopper 2 …… Solidification container, 3 …… Solidification material tank 4 …… Rolling kneader, 5 …… Storage tank 6 …… Waste supply tank, 7 …… Dryer 8 …… Exhaust gas Processing equipment, 9 …… Granulator 10 …… Mixing blade, 11 …… Hydraulic cylinder 12 …… Pressure spring, 13 …… Bearing 14 …… Rotary motor, 15 …… Holder 16 …… Revolution shaft.

Claims (2)

[Claims] 1. A pellet-like or powder-like radioactive waste and a paste-like solidifying material which is kneaded in advance by a solidifying material tank are put into a solidifying container, sealed, and solidified by using a rolling machine. After uniformly kneading the radioactive waste and the solidifying material in the solidification container by causing the container to perform a two-degree-of-freedom rotary motion of a rotary motion around the rotation axis and a rotary motion around the revolution axis, A method for solidifying radioactive waste, which comprises solidifying in the solidifying container. 2. A pair of holders for removably sandwiching a solidified container into which a radioactive waste in the form of pellets or powder and a paste-like solidifying material previously kneaded by a solidifying material tank are charged and sealed. An arm or frame that rotatably supports the tool and that is rotatably supported around an axis of revolution that intersects the axis of rotation of the holder, drive means for rotating the holder around the axis of rotation, The solidification container comprises a drive means for rotating the arm or frame around the revolution axis, and the solidification container is rotated in two degrees of freedom to uniformly knead the radioactive waste and the solidification material in the solidification container. A rolling machine for radioactive waste solidification treatment, characterized in that