CN112764078B - Nuclear material measuring device - Google Patents

Abstract

The invention relates to a nuclear material measuring device, comprising a material channel, a neutron measurement structure and an isotope detection structure; the material channel extends into the neutron measurement structure so that it can measure the neutrons of the nuclear material in the material channel ; The neutron measurement structure is provided with a detection slit matched with the isotope detection structure, so that the isotope detection structure can perform isotopic measurement on the nuclear material. The beneficial effects of the present invention are as follows: the present invention realizes the comprehensive measurement automation including neutron measurement and isotope measurement (γ measurement) by setting detection slits on the neutron measurement structure, avoids the radiation danger of operators, and ensures personnel safety. The invention can measure the nuclear materials distributed in different positions in the shelf, and at the same time can shield the nuclear radiation of the materials well, so that the radiation level of the measurement environment is kept at a low level.

Description

A nuclear material measuring device

technical field

The invention belongs to the field of nuclear industry, and particularly relates to a barrel material measuring device.

Background technique

For nuclear materials, especially plutonium-containing materials, the general purpose of measurement is to obtain the isotopic information and plutonium-containing mass of nuclear materials.

In the prior art, well-type neutron measurement equipment is generally used to measure the mass of plutonium, and then a high-purity germanium detector is used to measure the isotopic information of the material.

In actual operation, it is difficult to measure multiple nuclear materials placed in the sample rack. Nuclear materials used in the nuclear industry are dangerously radioactive. The radiation generated by these nuclear materials is extremely harmful to the human body, so the safety of operators must be ensured during the transfer of nuclear materials. However, high-purity germanium detectors often use open measurement for gamma measurement, and the operator needs to move the detector to align the measurement samples at different heights in the shelf during measurement, which has radiation safety problems.

And at present, there is no suitable equipment for comprehensive measurement and analysis of isotope and total plutonium mass for multiple nuclear materials with different isotopes placed in the rack.

In view of this, the present invention is proposed.

SUMMARY OF THE INVENTION

In view of the defects existing in the prior art, the purpose of the present invention is to provide a nuclear material measuring device, and the technical solution can realize automatic comprehensive measurement of nuclear materials.

The technical scheme of the present invention is as follows:

A nuclear material measurement device, comprising a material channel, a neutron measurement structure and an isotope detection structure; the material channel extends into the neutron measurement structure so that it can measure the neutrons of the nuclear material in the material channel; the The neutron measurement structure is provided with a detection slit matched with the isotope detection structure, so that the isotope detection structure can perform isotope measurement on the nuclear material.

Further, in the above-mentioned nuclear material measurement device, the neutron measurement structure includes a lead shielding layer, an inner polyethylene moderator, a graphite reflective layer, an outer polyethylene shielding body and a measurement component; the material channel extends into the The lead shielding layer forms a measurement cavity; the outer side of the lead shielding layer is sequentially covered with an inner layer polyethylene moderator, a graphite reflection layer and an outer layer polyethylene shielding body; the neutron detector of the measurement component is embedded in the inner layer layer of polyethylene moderator; the detection slit passes through the lead shielding layer, the inner layer of polyethylene moderator, the graphite reflective layer and the outer layer of polyethylene shielding body.

Further, in the above-mentioned nuclear material measuring device, the inner polyethylene moderator, the graphite reflective layer and/or the outer polyethylene shielding body are formed by stacking multiple plates of corresponding materials, and are connected to the inner polyethylene moderator by tightening the screw. The base of the neutron measurement structure is fixedly connected.

Further, in the above-mentioned nuclear material measurement device, the material channel includes a pre-buried pipeline, an intermediate pipeline and a measurement pipeline; wherein the pre-buried pipeline is pre-buried on the top of the measurement chamber, and the intermediate pipeline connects the pre-buried pipeline and the measurement pipeline; the lower end of the measurement pipeline positioned on the base of the neutron measurement structure.

Further, in the above-mentioned nuclear material measuring device, a step for cooperating with the nuclear material shelf is provided between the measuring pipe and the intermediate pipe.

Further, in the above-mentioned nuclear material measuring device, the isotope detection structure includes a vertical moving part and a detector platform; the isotope detector is installed on the detector platform, and the detector platform can drive the isotope detector along the detector platform. The vertical moving part is vertically moved to align the probe of the isotope detector with the nuclear material in the detection slit.

Further, in the above-mentioned nuclear material measurement device, the neutron measurement structure and the isotope detection structure are both disposed in the measurement chamber, and the material passage penetrates the chamber wall of the measurement chamber to extend into the neutron measurement structure.

The beneficial effects of the present invention are as follows:

1. The present invention realizes the comprehensive measurement automation including neutron measurement and isotope measurement (γ measurement) by setting detection slits on the neutron measurement structure, avoids the radiation danger of operators, and ensures the safety of personnel.

2. The present invention can measure the nuclear materials distributed in different positions in the shelf, and at the same time can shield the nuclear radiation of the materials well, so that the radiation level of the measurement environment is kept at a low level.

3. An independent measuring room is adopted. The measuring room is a concrete structure, and the operator operates outdoors, which can better reduce the risk of nuclear radiation for the operator;

4. The measurement cavity of the neutron measurement structure is wrapped with multi-layer shielding materials, so that the neutrons of the material to be measured can be measured by neutrons under the condition that the measurement reduces the environmental background and ensures that the radiation dose around the measurement equipment is within a safe range The tube is effectively captured to ensure the detection efficiency;

5. The neutron detector is embedded in the inner polyethylene moderator, which can better detect the neutron data of nuclear materials.

6. The isotope detector can move vertically, which can better scan the nuclear materials in the hanging cup shelf, and can automatically measure the positioning of the shelf materials of different specifications.

Description of drawings

FIG. 1 is a schematic structural diagram of a nuclear material measuring device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a neutron measurement structure according to an embodiment of the present invention.

FIG. 3 is a top view of FIG. 2 .

FIG. 4 is a schematic structural diagram of a material channel according to an embodiment of the present invention.

FIG. 5 is a schematic structural diagram of an isotope detection structure according to an embodiment of the present invention.

In the above drawings, 1. measurement room; 2. neutron measurement structure; 3. material channel; 4. isotope detection structure; 5. control system; 21. base; 22. lead shielding layer; 23. inner polyethylene slow chemical body; 24, graphite reflection layer; 25, outer polyethylene shielding body; 26, set-top box; 27, screw rod; 28, neutron detector; 29, screw rod; 31, embedded pipeline; 32, intermediate pipeline; 33, Measuring pipes; 34, shelves; 41, vertical moving parts; 42, isotope detectors.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

As shown in FIG. 1 , the present invention provides a nuclear material measurement device, comprising a material channel 3, a neutron measurement structure 2 and an isotope detection structure 4; the material channel 3 extends into the neutron measurement structure 2 so that it can measure The nuclear material in the material channel 3 is subjected to neutron measurement; the neutron measurement structure 2 is provided with a detection slit matched with the isotope detection structure 4 so that the isotope detection structure 4 can perform neutron measurement on the nuclear material. Isotope measurements.

The present invention realizes the comprehensive measurement automation including neutron measurement and isotope measurement (γ measurement) by setting detection slits on the neutron measurement structure 2, avoids the radiation danger of operators, and ensures the safety of personnel.

As shown in Figures 2 and 3, the neutron measurement structure 2 includes a lead shielding layer 22, an inner polyethylene moderator 23, a graphite reflection layer 24, an outer polyethylene shielding body 25 and a measurement component; the material channel 3 Protruding into the lead shielding layer 22 to form a measurement cavity; the outer side of the lead shielding layer 22 is sequentially covered with an inner layer polyethylene moderator 23, a graphite reflective layer 24 and an outer layer polyethylene shielding body 25; The neutron detector 28 (neutron measuring tube) is embedded in the inner polyethylene moderator 23; the detection slit passes through the lead shielding layer 22, the inner polyethylene moderator 23, the graphite reflection layer 24 and the outer layer Layer polyethylene shield 25. The set-top box 26 of the measurement assembly is arranged on the upper part of the neutron measurement structure 2 . The lead shielding layer 22 can shield gamma rays. The inner polyethylene moderator layer is mainly used for neutron moderation to ensure that the measuring tube can detect neutrons. The graphite reflection layer 24 is mainly used for neutron reflection, ensuring that the scattered neutrons can be reflected back into the neutron measuring tube to be detected, thereby improving the detection efficiency.

The inner polyethylene moderator 23, the graphite reflective layer 24 and/or the outer polyethylene shielding body 25 are formed by stacking multiple plates of corresponding materials, and the neutrons are connected to the neutron by tightening the screws (27, 29). The base 21 of the measuring structure 2 is fixedly connected.

The measurement cavity of the neutron measurement structure 2 is wrapped by a multi-layer shielding material, so that the neutrons of the material to be measured can be absorbed by the neutron measurement tube under the condition that the measurement reduces the environmental background and ensures that the radiation dose around the measurement equipment is within a safe range. Effective capture to ensure detection efficiency.

As shown in FIG. 4 , the material channel 3 includes a pre-embedded pipeline 31, an intermediate pipeline 32 and a measurement pipeline 33; wherein the pre-embedded pipeline 31 is pre-buried at the top of the measurement chamber 1, and the intermediate pipeline 32 connects the pre-embedded pipeline 31 and the measurement pipeline. 33; the lower end of the measurement pipe 33 is positioned on the base 21 of the neutron measurement structure 2. A step for matching with the nuclear material shelf 34 is provided between the measuring pipe 33 and the intermediate pipe 32 . According to the different specifications of the hanging cup racks, the hanging cup racks in the material channel 3 can be placed on the base 21 or hung on the steps.

As shown in FIG. 5 , the isotope detection structure 4 includes a vertical moving part 41 and a detector platform; the isotope detector 42 is installed on the detector platform, and the detector platform can drive the isotope detector 42 along the detector platform. The vertical moving part 41 moves vertically so that the probe of the isotope detector 42 is aligned with the nuclear material in the detection slit.

When the nuclear material measuring device of the present invention is in use, the operator controls it through the control system 5 , and the hanging cup rack containing nuclear material enters the measuring pipe 33 through the embedded pipe 31 and the intermediate pipe 32 of the material channel 3 . Then start the measurement system, the detection instrument enters the designated position to scan the nuclear material, and obtains the γ-ray data of the nuclear material; at the same time, the measuring tube in the inner polyethylene moderating layer obtains the neutron data, and obtains the material parameters through the nuclear data processing software. .

In this embodiment, both the neutron measurement structure 2 and the isotope detection structure 4 are arranged in the measurement chamber 1 , and the material channel 3 passes through the chamber wall of the measurement chamber 1 (in this embodiment, the top of the measurement chamber 1 ) ) to protrude into the neutron measurement structure 2 . The measuring room 1 is an independent measuring room with a concrete structure. The operator operates outdoors, which can better reduce the risk of nuclear radiation for the operator; the isotope detector 42 can move vertically, which can better scan the nuclear materials in the hanging cup shelf , and can automatically measure the positioning of shelf materials of different specifications.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their technical equivalents, the present invention is also intended to include such modifications and variations.

Claims (5)

1. A nuclear material measuring device is characterized by comprising a material channel, a neutron measuring structure and an isotope detection structure; the material channel extends into the neutron measurement structure so that the material channel can perform neutron measurement on nuclear materials in the material channel; the neutron measurement structure is provided with a detection slit matched with the isotope detection structure so that the isotope detection structure can carry out isotope measurement on the nuclear material, and the neutron measurement structure comprises a lead shielding layer, an inner polyethylene slowing body, a graphite reflecting layer, an outer polyethylene shielding body and a measurement component; the material channel extends into the lead shielding layer to form a measuring cavity; an inner polyethylene slowing-down body, a graphite reflecting layer and an outer polyethylene shielding body are sequentially coated outside the lead shielding layer; a neutron detector of the measuring assembly is embedded in the inner polyethylene moderating body; the detection slit penetrates through the lead shielding layer, the inner polyethylene slowing body, the graphite reflecting layer and the outer polyethylene shielding body, and the material channel comprises a pre-buried pipeline, an intermediate pipeline and a measuring pipeline; the embedded pipeline is embedded in the top of the measuring chamber, and the middle pipeline is connected with the embedded pipeline and the measuring pipeline; the lower end of the measuring pipeline is positioned on a base of the neutron measuring structure.

2. The nuclear material measuring device of claim 1, wherein the inner polyethylene moderator body, the graphite reflector layer, and/or the outer polyethylene shield body are formed by stacking a plurality of plates made of corresponding materials, and are fixedly connected to the base of the neutron measuring structure through fastening screws.

3. The nuclear material measuring device of claim 1, wherein a step for engaging with a nuclear material shelf is provided between the measuring pipe and the intermediate pipe.

4. The nuclear material measuring device of claim 1, wherein the isotope detection structure includes a vertically moving component and a detector platform; the isotope detector is arranged on the detector platform, and the detector platform can drive the isotope detector to vertically move along the vertical moving part so that the probe of the isotope detector is aligned with the nuclear material in the detection slit.

5. The nuclear material measuring device of any one of claims 1 to 4, wherein the neutron measuring structure and the isotope detection structure are both disposed within a measuring chamber, and the material passage passes through a chamber wall of the measuring chamber to extend into the neutron measuring structure.

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