JPS5926099A - Heating and drying for radioactive waste treating equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating and drying method for a radioactive waste treatment device, and in particular, to a method for heating and drying a radioactive waste treatment device, and in particular, a method for drying and evaporating radioactive waste liquid or slurry generated at a nuclear power plant, etc., and solidifying it. Heating of radioactive waste processing equipment suitable for heating waste processing equipment and drying after cleaning.

This relates to a drying method.

The first example of heating and drying methods for conventional radioactive waste processing equipment
This will be explained using figures.

Figure 1 shows the heating of a conventional radioactive waste treatment device.

A system diagram of the radioactive waste processing equipment that implemented the drying method.
Liquid supply pump 10. A heating jacket 11 connected to a conduit 50 provided with a liquid supply valve 30 and connected to conduits 51 and 52 for heat medium supply and discharge is enclosed, and is driven by a drive device 12 such as an electric motor. A drying device 14, in which a rotary blade 13 is rotatably housed, is connected at one end to a drying material hopper 15 and a drying material hopper 51 through a drying material discharge pipe via a drying material valve. ,
A tweeter 18 with a screw 17 driven by the screw drive device 16, a drain tank 19 connected to one end of the feeder 18 by a conduit 54 provided with a drain valve 32, and a feeder outlet at the other end of the feeder 18. The solidification treatment device i! is connected by a conduit 55 via a valve 33, and is composed of an assimilation material mixing device and an assimilating material mixing device, which are connected to each other by a conduit 55 and a conduit provided with a solidified material gate valve. 21 is connected to the conduit 57, which is also provided with a condensate outlet valve, and a conduit 57 for supplying cooling water;
Condenser η to which discharge conduits 58 and 59 are respectively connected
and a vent outlet valve 36 of conduit 60 connected to condenser n.
．． A conduit 61 connects an evaporation treatment device path consisting of a suction tank and a suction tank provided between 37 and 37. Note that a dehumidifying device w125 is connected to the assimilating material mixing device through a conduit 62 provided with a valve gap.

Radioactive waste such as radioactive liquid waste or slurry generated at a nuclear power plant or the like is supplied at a predetermined supply capacity from a liquid supply pump 10 to a drying device 14 via a liquid supply valve 3 () and a conduit W50. Here, radioactive waste is a waste! The drying bag f is formed by the centrifugal force of the rotary blade 13 driven and rotated by the device 12.
It is spread into a thin film on the inner wall surface of i14, and is evaporated and dried by the heating of the heating medium flowing through the pipe 52. Evaporated matter passes through conduit 6e to condenser 2
2I is supplied here, is supplied from between the conduits, and is condensed with the cooling water discharged from the conduit 59, and the R agent liquid 1 or 1 is
17t, and is sent to another water treatment device (not shown) through a conduit 57 via a chemical solution outlet valve 35. Further, the non-condensable gas in the evaporated matter is sucked by the suction device n via the vent outlet valve 36, and is sent to another vent treatment device i (not shown) via the vent outlet valve 37 through the conduit 60. On the other hand, the dried material is supplied to one end of the feeder 8 via the dried material outlet pipe 53 and the dried material valve 31, and is transferred to the other end of the feeder 8 by the screw 17 driven by the screw drive device 16. The dried material transferred to the other end of the feeder 8 is fed through the feeder outlet valve 33 and the conduit 55 to the solidification treatment equipment, where it is mixed with a solidified layer of asphalt or plastic, etc., and then passed through the solidified material gate valve. It is supplied and filled into an assimilation drum 70 through a conduit 56 through an aperture. In addition, the drain accumulated at one end of the feeder 8 is extracted and stored in the drain tank 19 via the drain valve 32 and the conduit. In order to perform this series of processing smoothly, it is necessary to keep the radioactive waste processing equipment in good health. must be maintained. In other words, since radioactive waste is usually dried by evaporation to a residual moisture content of several percent by weight or less, the distribution path of the dried material from the drying device 14 to the solidification processing device 21 (hereinafter abbreviated as the distribution path of the dried material) If the machine is not completely dry before operation, dry matter will adhere to areas where moisture remains, and
This leads to the growth of solids and impedes smooth operation. Also,
If the distribution path of the dried material is lower than the temperature of the dried material, that is, close to room temperature, a small amount of residual moisture in the dried material or evaporated matter discharged together with the dried material may enter the distribution path of the dried material. It condenses and adheres, which leads to the adhesion and growth of solids and impedes smooth operation. Therefore, in order to solve these problems and operate the radioactive waste processing equipment smoothly, the radioactive waste processing equipment has conventionally been heated using the following method.

It has been dried.

First, to heat the radioactive waste processing equipment before processing radioactive waste, an electric heater or heating jacket is installed in each passage of the dried material, and the electric heater or heating jacket is used to adjust the passage of the dried material to the temperature of the dried material. For example, drying of the radioactive waste treatment equipment after cleaning is done by heating it to a higher temperature than the dehumidifier RY12!5.
The dehumidified dry air is supplied to the solidification processing device 21 through the conduit 62 between the valves, and the dried material is circulated in the opposite direction through the distribution path.

This heating and drying method for radioactive waste processing equipment has the following drawbacks.

(1) Some parts, such as the drive mechanism, are not sufficiently heated locally, and therefore, it takes a long time to warm up, or heating tends to be insufficient.

(2) After cleaning, it is difficult to completely dry the stagnation part with dry air, and therefore it takes a long time to completely dry it.

Therefore, the present inventors proposed a heating and drying method for a radioactive waste processing apparatus described in Japanese Patent Application No. 57-022739 with the aim of eliminating the above-mentioned drawbacks.

FIG. 2 illustrates an embodiment of the method proposed above, and FIG. 2 shows the same apparatus as FIG. 1.

Parts are designated by the same reference numerals and their explanations are omitted.

′! In FIG. 52, a conduit 63 provided with a valve 39 and open to the atmosphere at one end is connected to a conduit 60 between the vent Yamaguchi valve 36 and the suction device [Z3, and is connected between the suction device 1i23 and the vent Yamaguchi valve 37. A conduit θ branched from the conduit 60 and provided with a valve 40 is connected to the conduit 61. In addition, assimilation processing equipment [
The assimilation treatment device 21 is provided with valves 41 and 42,
A conduit 65 with one end open to the atmosphere is connected to the valve 41.4.
A conduit 66 branched from the conduit 65 between the two and provided with a valve 43
is connected to the conduit 60 on the upstream side of the suction device n. Heating of such radioactive waste processing equipment.

Drying is performed as follows.

Between the liquid supply valve and the drain valve 32. Solidified product gate valve A, condensate Yamaguchi valve, vent outlet valve 36737. Close valve 42 and close dry product valve 31. Feeder outlet valve 33. Valve 39-41.43
After opening the valve, the suction device 1123 is driven. Gas, for example air, is thereby passed through valve 39 to conduit 63.6.
After being sucked into the suction device t23 via a conduit 60, the liquid is supplied to the drying device 14 via a valve 40 and conduits d and 61. The air supplied to the drying device 14 is passed through the conduit 51
゜Heating jacket 11. After being heated by the heat medium flowing through the conduit 52, this heated air is passed through the drying device 14.
from the dry matter outlet pipe 53 to the dry matter hopper of the assimilation treatment device 21, and the dry matter hopper 15. Dry product valve 31. Feeder 18. Nida outlet valve 33. Conduit 55. It sequentially flows through the solidification feather mixer (a) and is discharged from the conduit 65 via the valve 41. During this time,
The distribution path of the dried material is sufficiently heated and dried by the heated air. Note that the air discharged from the solidification processing device 21 may be returned to the upstream side of the suction device section via the valve 43 and the conduit 6, and re-supplied to the drying bag [+\14] by the suction device. , the valve 42 may be opened, the valve 43 may be closed, and the gas may be discharged to the atmosphere via the valve 42 and the conduit 65.

Although this method has the effect of sufficiently heating and drying the distribution route of dried products in a short period of time, a more detailed study revealed that it still has the following drawbacks. Ta.

l) The gas that heats and dries the distribution route of the dried material is accompanied by radioactive particles and is discharged from the system as it is, which poses an obstacle to the protection of the working environment and workers.

The purpose of the present invention is to solve the above-mentioned drawbacks, such as ``allowing the distribution route of dried materials to be sufficiently heated and dried in a short period of time, and preventing obstacles in protecting the working environment and workers.'' An object of the present invention is to provide a heating and drying method for a radioactive waste processing equipment that can eliminate the

The present invention is characterized by supplying gas to the drying device, heating the gas by a heating medium flowing through a heating jacket enclosed in the drying device, and supplying the gas from the drying device to the assimilation treatment device via the dried material outlet pipe. By distributing the radioactive particles, removing the entrained radioactive particles with a radioactive particle removal means, and then discharging them out of the system, the distribution path of the dried material is heated, and the dried gas is sent out of the system without accompanying radioactive particles. It consists in expelling.

An embodiment of the present invention will be described with reference to FIG. In addition, the third
This figure shows the same equipment as Kaya Figures 1 and 2.

Parts, etc. are indicated by the same reference numerals and explanations are omitted.

In FIG. 3, a conduit 66 and a U-shaped seal tube 67 connected to the conduit 61 at one end are arranged in the lower part of the radioactive particle removal means, for example, the mist separator 80, and in the upper part, the conduit 5 is connected to the conduit 61 at one end.
7 and a conduit side provided with a wash water supply valve 44, a conduit 69 whose one end is connected to a condenser n is connected to the top, and a conduit 70 is connected to the bottom.

A gas, for example air, entrained with radioactive particles is passed through valve 41.
By opening the valve 43 and the valve 42, the water is supplied to the lower part of the mist separator 80 through the conduits 65 and 66, and rises inside the mist separator 80. On the other hand, by opening the valve a, the cleaning water is supplied to the upper part of the mist separator lake 80 through the conduit section, and flows down inside the mist separator lake 80. During this time, the air in the upper row and the washing water flowing down come into gas-liquid contact, and as a result, the radioactive particles entrained in the air are not removed from the air. Thereafter, the wash water containing the radioactive particles is extracted from the bottom of the mist cell/sl leak 80 through the conduit 70 to the outside of the system and treated. On the other hand, the clean air from which radioactive particles have been removed is supplied to the condenser n via the top of the mist separator 800 and the conduit 69, where moisture is removed. Thereafter, this air is sucked by the suction blade and discharged out of the system through the conduit 60. In addition, when the valve 39 is opened, this air is mixed with air sucked from the outside into the conduit 60 through the conduit 63, and is returned to the drying device 14 via the valve 40 and conduits B and 61. It may also be supplied.

Incidentally, the heating and drying operations of the distribution path of the dried material are the same as those explained in FIG. 2, and therefore, the explanation will be omitted.

In the method of this embodiment, air heated by a drying device is passed through the distribution path of the dried material to heat and dry the material, and
After the accompanying radioactive particles are removed by the mist separator, the air is discharged to the outside of the system, resulting in the following effects.

(1) The distribution route for dried products can be sufficiently heated and dried in a short time.

(2) Obstacles in maintaining the working environment and winter workers can be eliminated.

As explained above, the present invention supplies gas to a drying device, heats the gas by a circulating heating medium through a heating jacket enclosed in the drying device ζ, and supplies the gas from the drying device via a dried material outlet pipe. By supplying the dried material to the solidification processing equipment and distributing it, removing the entrained radioactive particles with the radioactive particle removal means and then discharging it outside the system, the distribution route of the dried material can be sufficiently heated and dried in a short time. This has the effect of eliminating obstacles to protecting the work environment and workers.

[Brief explanation of the drawing]

Fig. S1 is a system diagram of a conventional radioactive waste processing equipment, and Fig. 2 is a diagram of a radioactive waste processing equipment that implements the heating and drying method for radioactive waste processing equipment proposed earlier by the inventors. FIG. 3 is a system diagram showing an example of a radioactive waste processing apparatus in which the present invention is implemented.

Claims (1)

[Claims] 1. A drying device for drying radioactive waste in which rotary blades are rotatably arranged inside and a heating jacket through which a heat medium flows is enclosed, and an evaporated matter processing device that condenses the evaporated matter; and a solidification processing device that is connected to the drying device through a dry matter outlet pipe and solidifies the dried matter discharged from the drying device through the outlet pipe. In a method for heating and drying a radioactive waste treatment device, gas is supplied to the drying device, the gas is heated by a heating medium flowing through the heating jacket, and the gas is passed from the dry treatment device through the dried material outlet pipe. A heating and drying method for a radioactive waste processing apparatus, characterized in that the radioactive waste is supplied to the solidification processing apparatus and distributed, and the entrained radioactive particles are removed by a radioactive particle removal means and then discharged to the outside of the system. 2. The heating and drying method for a radioactive waste processing apparatus according to claim 5, wherein radioactive particles entrained in the gas are removed by a minutosebare lake.