JPH11142260A - Heating value measuring instrument for glass solidification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new heating value measuring instrument which can accurately find the total heating value of a glass solidified body by greatly reducing its heat flux measurement error. SOLUTION: This instrument includes a flank heat flux measurement part 4 equipped with side heat flux sensors 10 which measure heat flux on the flank of a solidified body container 2 vertically in stages so that they are allowed to freely come closer and leave one another, and a bottom heat flux measurement part 5 equipped with a bottom heat flux sensor 16 which measure the heat flux at the bottom of the solidified body container 2. Consequently, the heat flux can be measured not only on the flank of the solidified container 2, but also from the bottom part of the solidified body container 2, so the measurement error can be greatly decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calorific value measuring device for remotely measuring the calorific value of a vitrified body that generates high heat.

[0002]

2. Description of the Related Art Conventionally, spent fuel from a nuclear power plant is separated into uranium and plutonium which can be reused in a reprocessing plant and fission products to be discarded, and then the fission products have a high level. After being melted together with the glass raw material at a high temperature as a radioactive waste liquid, it is placed in a stainless steel cylindrical container called a canister and is stabilized as a vitrified body.

[0003] Since the vitrified material has been heated to a high temperature due to decay heat for a while, it is naturally cooled while being stored and stored for about 30 to 50 years in a vitrified material storage building constructed outdoors. After that, it is planned to be buried deep underground.

[0004] At present, reprocessing of this spent fuel is outsourced to a foreign reprocessing plant, and the vitrified material generated during the reprocessing is returned to Japan with uranium and plutonium, and ultimately, domestically. It is to be disposed of at a processing facility. Therefore, after the vitrified waste generated in a foreign reprocessing plant is transported to Japan and before being stored and disposed of, the appearance and calorific value of the vitrified waste should be inspected in a domestic vitrified glass inspection room in accordance with Japanese security regulations. Various measurements and inspections such as dimensional measurement, weight measurement, confinement inspection, surface contamination inspection, and radioactivity measurement are to be performed.

[0005]

Among these measurements and inspections, the calorific value measurement method currently includes mounting a solidified container on a turntable, and rotating a solid container on a side surface of the container while rotating the container. By contacting the flux sensor and measuring the heat flux from the side surface (the amount of heat moving across a unit area per unit time per unit time) in upper and lower stages, the total heat generation of the vitrified body is calculated. I have.

However, in such a measuring method,
Since the heat flux from the bottom cannot be measured, it has been difficult to accurately measure the total calorific value of the vitrified body. Also, if there is a gap between the solidified container and the heating element (high-level radioactive waste) contained in the container, heat transfer is not performed well, Large errors sometimes occurred.

Accordingly, the present invention has been devised in order to effectively solve such a problem, and an object of the present invention is to significantly reduce the measurement error of the heat flux of the vitrified body and to reduce the total calorific value thereof. And a novel calorific value measuring device that can be obtained.

[0008]

In order to solve the above-mentioned problems, the present invention measures the calorific value of a vitrified body in which a heating element made of high-level radioactive waste is accommodated in a cylindrical solidified body container. In the apparatus for, the side heat flux measurement unit provided with a plurality of side heat flux sensors so as to be able to approach and separate freely in order to measure the heat flux on the side of the solidified container in multiple stages, and the heat flux on the bottom of the solidified container. And a bottom heat flux measuring unit provided with a bottom heat flux sensor for measurement.

Therefore, the device of the present invention can measure not only the side surface of the solidified body container but also the heat flux from the bottom of the solidified body, so that the total calorific value of the vitrified body can be accurately calculated.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of an apparatus for measuring a calorific value of a vitrified body according to the present invention. In addition, 1 in the figure
Is placed inside a cylindrical solidified container 2 made of stainless steel.
It is a vitrified body containing the heating element 3 which is a high-level radioactive waste.

As shown in FIG.
It mainly comprises a side heat flux measuring section 4 for measuring the heat flux on the side surface of the solidified container 2 and a bottom heat flux measuring section 5 for measuring the heat flux on the bottom surface of the solidified container. The measuring unit 4 and the bottom surface heat flux measuring unit 5 are integrally fixed on a base 6.

The side heat flux measuring section 4 is provided with a plurality of arms 8 extending vertically to the vitrified body 1 on a column 7 vertically erected on a base 6 in a vertically multi-stage manner. At the tips of 8, 8 drive mechanisms 9,
Heat flux sensors 10, 10, 10 are provided via 9, 9, and these heat flux sensors 10, 10, 10, 10 are provided.
Thereby, the heat flux from the side surface of the vitrified body 1 can be measured in upper and lower stages.

As shown in FIG. 3, the drive mechanism 9 has a rod screw 11 provided with a heat flux sensor 10 at the tip thereof, and supports the rod screw 11 horizontally and has a tip attached to the vitrified body 1 as shown in FIG. The driving gear 14 includes a moving gear 12 that horizontally moves in a direction, and a driving motor 14 that drives the moving gear 12 via a driven gear 13. By driving the driving motor 14 in one of forward and reverse directions,
The heat flux sensor 10 at the tip of the rod screw 11 can be brought into contact with or separated from the surface of the solidified body container 2 of the vitrified body 1.

On the other hand, as shown in FIG. 2, the bottom heat flux measuring unit 5 includes a rotating base 15 on which the bottom surface of the vitrified body 1 is mounted.
And a heat flux sensor 16 located at the center of the rotary base 15, and a lifting mechanism 1 for raising and lowering the bottom heat flux sensor.
7 mainly. In addition, this rotating base 15
As shown in FIG. 1, a ring-shaped rotary table 20 is provided on a table base 18 via a ball bearing 19, and this rotary table 20 is connected to a drive motor 21.
The rotary table 20
The vitrified body 1 mounted thereon can be arbitrarily swiveled about its axis. Elevating mechanism 1
As shown in FIG. 2, 7 comprises a rod screw 22 provided with a heat flux sensor 16 at the upper end thereof, and an elevating motor 23 for vertically moving the rod screw 22 vertically. Then, the heat flux is brought into contact with the bottom surface of the vitrified body 1 so that the heat flux at that portion can be measured.

The heat flux sensors 10 and 16 are not particularly limited as long as they have heat resistance, radiation resistance and the like with respect to the vitrified body 1. For example, E500B, E750, EF, Commercially available products such as EG (all manufactured by Kyoto Electronics Industry Co., Ltd.) can be applied as they are. In FIG. 1, reference numeral 24 denotes a monitor for remotely monitoring the state of the vitrified body 1.

Then, as shown in FIG. 1, the vitrified body 1 is placed on the bottom heat flux measuring unit 5 by an overhead crane or the like (not shown), and then the driving mechanism 9 of the side heat flux measuring unit 4 is driven. Each of the heat flux sensors 10, 10, 10 is brought into contact with the side surface of the solidified solid container 2 of the vitrified solid to form the solidified solid container 2.
The heat flux from the side of the solidified container 2 is measured by driving the elevating mechanism 17 of the bottom surface heat flux measuring unit 5 to bring the heat flux sensor 16 into contact with the bottom of the solidified container 2. Will be measured.

Therefore, even if a gap is formed between the solidified container 2 and the heating element 3, the error in the measured value of the heat flux of the solidified container 2 can be greatly reduced. In particular, as shown in FIG. 1, since the bottom surface of the solidified container 2 is recessed upward (inward), the heating element 3 inside the solidified container 2 is always in the solidified container 2.
, It is possible to always accurately measure the heat flux on the bottom surface of the solidified container 2.
Then, each of these heat flux sensors 10, 10, 10, 16
By calculating based on the measured values obtained in the above, it is possible to accurately know the total calorific value of the vitrified body 1.

Further, since the vitrified body 1 is mounted on a rotatable rotary base 15, the vitrified body container 2
When there is a large gap between the heating element 3 and
It is also possible to rotate the vitrified body 1 to perform measurement at an appropriate position, so that measurement with less error can be performed.

In the present embodiment, three heat flux sensors 10 and 10 are provided to measure the side heat flux of the vitrified body 1.
Although 10 and 10 are provided in upper and lower stages, it is needless to say that this number may be increased or decreased as needed, but if the heat flux on the bottom surface of the vitrified body 1 can be measured as in the present invention, It is possible to reduce the number.

[0021]

In summary, according to the present invention, since the heat flux on the bottom surface as well as the side surface of the vitrified body can be measured, the measurement error of the heat flux of the vitrified body can be greatly reduced, Excellent effects such as the fact that the total amount of heat of the solidified body can be accurately calculated can be exhibited.

[Brief description of the drawings]

FIG. 1 is an overall view showing an embodiment of a calorific value measuring device according to the present invention.

FIG. 2 is a perspective view showing a configuration of a bottom heat flux measuring unit according to the present invention.

FIG. 3 is a cross-sectional view illustrating a configuration of a side heat flux measuring unit according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vitrified body 2 Solidified body container 3 Heating element 4 Side heat flux measurement part 5 Bottom heat flux measurement part 10,16 Heat flux sensor

Claims (2)

[Claims] 1. An apparatus for measuring a calorific value of a vitrified body in which a heating element made of high-level radioactive waste is accommodated in a cylindrical solidified body container, wherein the heat flux on the side surface of the solidified body container is increased and decreased. A side heat flux measuring unit provided with a plurality of side heat flux sensors so as to be close to and separated from each other for multi-stage measurement, and a bottom heat flux provided with a bottom heat flux sensor to be able to move up and down to measure the heat flux on the bottom surface of the solidified container. A heat rate measuring device, comprising: a bundle measuring unit. 2. The heat flux measuring unit according to claim 1, wherein the bottom heat flux measuring unit includes a rotary mount on which the solidified container is placed, a heat flux sensor located at a central portion of the rotary mount, and an elevating mechanism for raising and lowering the heat flux sensor. The apparatus for measuring a calorific value of a vitrified body according to claim 1, wherein: