KR20110097217A - Waste heat generator - Google Patents

Abstract

It provides a waste heat generator that can generate waste heat of waste such as nuclear waste and use it as alternative energy. The waste heat generation apparatus is adapted to receive nuclear waste and includes a nuclear waste storage container extending in one direction, a thermoelectric device surrounding at least one side of the nuclear waste storage container, and a radioactive shield member surrounding the thermoelectric device.

Description

Waste heat generating device {APPARATUS FOR GENERATING ELECTRICITY BY UTILIZING WASTE HEAT}

The present invention relates to an apparatus using waste heat of nuclear waste, and more particularly, to a waste heat power generation apparatus using high-level nuclear waste.

As the use of energy increases rapidly due to the development of the current industry, active alternatives to future depletion of energy sources, such as the development of alternative energy and the effective use of waste energy, are required.

In order to cope with this energy depletion reality, some developed countries are actively researching and developing thermoelectric materials having high thermoelectric properties for large-scale power generation using natural energy such as sea water temperature difference and solar heat. In addition, in order to cope with an increase in environmental awareness and exhaustion of fossil fuels, research and development are being conducted to efficiently use waste heat for power generation using a thermoelectric conversion system.

Specifically, at present, high-level nuclear waste consisting of nuclear fuel rods is discarded by using a costly method, but the present invention intends to simultaneously process nuclear waste while generating and recovering waste heat from nuclear waste. .

It provides a waste heat generator that can generate waste heat of waste such as nuclear waste and use it as alternative energy.

The waste heat generation apparatus is adapted to receive nuclear waste and includes a nuclear waste storage container extending in one direction, a thermoelectric device surrounding at least one side of the nuclear waste storage container, and a radioactive shield member surrounding the thermoelectric device.

The thermoelectric device includes lead, the thermoelectric device may primarily shield the radiation emitted from the nuclear waste, and the radiation shield member may shield the radiation secondary. The thermoelectric device may include a high temperature junction that receives heat in contact with the nuclear waste storage container, a low temperature junction that contacts the radioactive shield member, and a plurality of thermoelectric elements connected between the high temperature junction and the low temperature junction. The temperature difference between the hot junction and the cold junction may be 400 ° C. to 600 ° C.

It further comprises a heat insulating material in contact with the upper and lower surfaces of the nuclear waste storage container and the side of the nuclear waste storage container, and a pair of lead wires through the top thermal insulation material, the pair of leads can be connected to the hot junction and the cold junction, respectively have. The heat insulator may seal the waste heat generating device to block the waste heat generating device from the outside thereof.

Thermoelectric element is one selected from the group consisting of bismuth-tellurium (Bi-Te) -based, lead-tellurium (Pb-Te) -based, silicon-germanium (Si-Ge) -based and ferro-silicon (Fe-Si) -based alloys It may contain more than one element. The thermoelectric element may comprise lead. In the case of PbTe, the amount of lead is about 30 wt% to 70 wt%. The thermoelectric elements may be formed spaced apart from each other, and the lengths of the thermoelectric elements may be substantially the same.

The nuclear waste storage container includes a plurality of sides, and at least one mutually adjacent pair of sides of the plurality of sides may be perpendicular to each other. At least one side of the nuclear waste storage container may have a curvature.

The apparatus may further include a heat transfer member positioned between the thermoelectric device and the radiation shielding member and in contact with the thermoelectric device and the radiation shielding member. Heat transfer members include thermal interface materials (TIMs), thermal greases, thermal bonds, thermally conductive silicone pads, thermally conductive adhesive tapes, and graphite sheets. Sheet) may include one or more elements selected from the group consisting of.

Waste heat generators generate electricity using heat sources from high-level nuclear waste.

In addition, by recovering the enormous amount of waste heat that is discarded through high-level nuclear waste, it is possible to realize energy saving by increasing power generation efficiency.

1 is a perspective view showing a state in which the waste heat generator according to the first embodiment of the present invention in water.
2 is a cross-sectional view taken along the line AA of FIG. 1.
3 is a partial cross-sectional view of the waste heat generating apparatus according to the second embodiment of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” include plural forms as well, unless the phrases clearly indicate the opposite. As used herein, the term "comprising" embodies a particular characteristic, region, integer, step, operation, element, and / or component, and other specific characteristics, region, integer, step, operation, element, component, and / or group. It does not exclude the presence or addition of.

Unless defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

The term "nuclear waste" as used below means all wastes that are disposed of in nuclear power generation. For example, radioactive waste or radioactive waste is included in nuclear waste.

1 shows a state of use of the waste heat generating apparatus 100 according to the first embodiment of the present invention. As shown in FIG. 1, in the waste heat generator 100, the lead wire 28 is exposed to the outside while being stored in the water 10.

Referring to FIG. 1, the waste heat generator 100 is stored in water 10. The waste heat generator 100 recovers waste heat of the used nuclear waste by using a thermoelectric device 20 (shown in FIG. 2).

The nuclear waste storage container 12 (shown in FIG. 2) is stored inside the waste heat generator 100, and remains sealed through the radioactive shielding member 30 and the heat insulating materials 50 and 52. Waste heat of the nuclear waste is thermoelectrically converted in the thermoelectric device 20 (shown in FIG. 2) and connected to an external power source through the lead wire 28.

Since the nuclear wastes dissipate heat, the nuclear wastes are stored in the nuclear waste storage container 12 while being cooled and stored in a storage pool or an intermediate storage facility or stored in the ground. In this case, the heat released from the nuclear waste may not be effectively utilized and may be released to the outside as it is. The waste heat generating apparatus 100 arranges the thermoelectric device 20 (shown in FIG. 2) to surround the nuclear waste storage container 12. In addition, the waste heat flow may be guided around the nuclear waste storage container 12 through the radioactive shielding member 30 and the insulations 50 and 52 to effectively utilize the waste heat emitted from the nuclear waste. Hereinafter, the internal structure of the waste heat generator 100 will be described in more detail with reference to FIG. 2.

FIG. 2 is a cross-sectional view of the waste heat generator 100 taken along line A-A of FIG. 1. 2 shows the internal structure of the waste heat generator 100 in detail.

Referring to FIG. 2, the waste heat generator 100 includes a nuclear waste storage container 12, a thermoelectric device 20, a radioactive shield member 30, a heat transfer member 40, and thermal insulation materials 50, 52. do. In addition, the waste heat generation apparatus 100 may further include other elements.

The nuclear waste storage container 12 accommodates nuclear waste. Meanwhile, the nuclear waste storage container 12 has a shape extending in one direction. The nuclear waste storage container 12 stores high-level nuclear waste. The waste heat generator 100 has a space in which the nuclear waste storage container 12 can be accommodated.

The thermoelectric device 20 has a shape surrounding at least one side of the nuclear waste storage container 12. The thermoelectric device 20 primarily shields the radiation emitted from the nuclear waste, including lead.

The radiation shielding member 30 has a shape surrounding the thermoelectric device 20. The radioactive shield member 30 includes lead (Pb). The radiation shielding member 30 shields the radiation emitted from the nuclear waste secondary. Since the radiation is primarily shielded using the thermoelectric device 20 and then the radiation is secondarily shielded using the radiation shielding member 30, the amount of radiation emitted from the nuclear waste storage container 12 can be minimized. have.

As shown in FIG. 2, the thermoelectric device 20 includes a high temperature junction 22, a low temperature junction 24, and thermoelectric elements 26. In addition, the thermoelectric device 20 may further include other elements as necessary.

The hot junction 22 is in contact with the nuclear waste storage container 12 receives heat. The high temperature junction 22 is formed in a plate shape in order to maximize the heat generated from the nuclear waste storage container 12 in surface contact with the nuclear waste storage container 12.

On the other hand, the low temperature junction 24 is in contact with the radioactive shielding member 30. The low temperature joint 24 is formed in a plate shape so as to be in surface contact with the radiation shield member 30 in order to lower the temperature as much as possible.

The thermoelectric elements 26 are connected between the high temperature junction 22 and the low temperature junction 24. The thermoelectric elements 26 are made of bismuth-tellurium (Bi-Te) -based, lead-tellurium (Pb-Te) -based, silicon-germanium (Si-Ge) -based, and ferro-silicon (Fe-Si) -based alloys. It includes one or more elements selected from the group. As described above, the thermoelectric elements 26 may include various materials.

The materials of the thermoelectric element 26 have different performances in their temperature ranges. For example, Bi-Te-based materials are mainly used in a temperature environment of about 200 ° C. or less, Pb-Te-based materials are used in a temperature environment of about 400 ° C., and Si-Ge-based materials are used at higher temperatures. These materials exhibit relatively good properties in the aforementioned temperature ranges.

The waste heat generator 100 may use lead-tellurium (Pb-Te) -based thermoelectric elements 26. The thermoelectric elements 26 include lead, and the amount of lead included in the thermoelectric elements 26 may be 30 wt% to 70 wt%. When the amount of lead included in the thermoelectric elements 26 is less than 30 wt%, the shielding effect of radioactivity may be reduced. In addition, when the amount of lead contained in the thermoelectric elements 26 exceeds 70 wt%, the thermoelectric efficiency of the thermoelectric elements 26 is reduced. Therefore, the amount of lead contained in the thermoelectric elements 26 is substantially 50wt%.

The thermoelectric elements 26 are formed spaced apart from each other. Here, the lengths of the thermoelectric elements 26 may be formed substantially the same. The thermoelectric elements 26 include n-type thermoelectric elements and p-type thermoelectric elements. The n-type thermoelectric element and the p-type thermoelectric element are electrically connected in series. On the other hand, the n-type thermoelectric element and the p-type thermoelectric element has a structure connected in parallel.

On the other hand, since the power generation efficiency improves as the temperature difference between the high temperature junction 22 and the low temperature junction 24 in the thermoelectric device 20 increases, it is better to keep the temperature of the low temperature junction 24 low. For this reason, the waste heat generator 100 may be immersed in water 10 to lower the temperature of the low temperature junction 24. For example, the waste heat generator 100 may be disposed at a portion for discharging the cooling water passing through the condenser of the nuclear power plant.

The insulations 50, 52 abut the upper and lower surfaces of the nuclear waste storage container 12 adjacent to the side of the nuclear waste storage container 12. Insulation materials 50 and 52 may include concrete. By bonding the insulators 50, 52 to the top and bottom of the nuclear waste storage container 12, the heat generated from the high level nuclear waste must be controlled to be released to the outside through the thermoelectric elements 26.

Referring to Figure 2, the upper and lower portions of the nuclear waste storage container 12 to block heat and radiation to the heat insulating material (50, 52) having the insulation and radiation shielding effect so that the waste heat of nuclear waste flows only to the side wall. The high temperature junction 22 of the thermoelectric device 20 is attached to the side wall of the nuclear waste storage container 12. The low temperature junction 24 of the thermoelectric device 20 uses heat transfer material, which is the heat transfer member 40, to allow heat to be transferred to the radiation shielding member 30 made of lead. Lead, which is a radiation shielding member 30, is a good heat transfer material, so that heat can be exchanged well with the outside, and at the same time, there is an effect of shielding radiation.

The insulations 50 and 52 seal the waste heat generator 100 to block the waste heat generator 100 from the outside thereof. Therefore, even when the waste heat generator 100 is immersed in the water 10, it is possible to prevent the water 10 from penetrating into the waste heat generator 100.

The pair of lead wires 28 penetrate the top insulation 50. The pair of lead wires 28 includes a positive lead wire 28a and a negative lead wire 28b. The pair of lead wires 28 are respectively connected to the high temperature junction 22 and the low temperature junction 24. The temperature difference between the high temperature junction 22 and the low temperature junction 24 may be 400 ° C to 600 ° C. If the temperature difference is less than 400 ° C, power generation efficiency is low, and if the temperature difference is too large, expensive materials should be used as the material of the thermoelectric element. Electromotive force may be generated by moving a carrier in the thermoelectric elements 26 using the temperature difference between the thermoelectric elements 26.

For reference, high-level waste at 400 ° C. has a heat generation rate of about 2 kW / m ³ to 20 kW / m ³ . Assuming that the volume of the nuclear waste storage container 12 is 1 m ³ , when the waste heat generator 100 according to the embodiment of the present invention is applied to waste heat recovery (external conditions are water of 10 ° C.), the Pb-Te alloy ( Tl-PbTe, ZT = 1.5) can recover energy of about 16.8%, or 0.3 ~ 3.4kW.

As shown in FIG. 2, the heat transfer member 40 is located between the thermoelectric device 20 and the radiation shielding member 30. The heat transfer member 40 is in contact with the thermoelectric device 20 and the radiation shielding member 30. The heat transfer member 40 includes a thermal interface material (TIM), a thermal grease, a thermal bond epoxy bond, a thermally conductive silicone pad, a thermally conductive adhesive tape, and graphite. One or more elements selected from the group consisting of a sheet may be included.

Referring to FIG. 2, the nuclear waste storage container 12 includes a plurality of sides, and at least one mutually adjacent pair of sides of the plurality of sides may be perpendicular to each other. For example, the nuclear waste storage container 12 may be formed in a cuboid shape. In addition, the nuclear waste storage container 12a may be formed such that at least one side thereof has a curvature. For example, the side surface of the nuclear waste storage container 12a may be formed in a curved shape, and a cross section of the nuclear waste storage container 12a may be manufactured in a circular shape.

3 is a partial cross-sectional view of the waste heat generating apparatus according to the second embodiment of the present invention. In FIG. 3, the space in which the nuclear waste storage container 12a is stored and the shape of the radioactive shield member 30a are different from the corresponding shapes in FIG. 1.

Referring to FIG. 3, the waste heat generator 200 forms a cylindrical cylindrical storage space in which a columnar nuclear waste storage container 12a is stored. And the radioactive shielding member 30a is also formed in a cylindrical shape. And the shape of the high temperature junction part 22a which comprises the thermoelectric device 20a also has a different shape. That is, the surface of the hot junction 22a in contact with the nuclear waste storage container 12a is formed in a circular shape. In addition, the surface where the nuclear waste storage container 12a is in contact with the thermoelectric elements 26a is formed in a plate shape. Therefore, since the high temperature junction 22a is in surface contact with the nuclear waste storage container 12a and the thermoelectric elements 26a, respectively, there is an advantage of high heat transfer efficiency.

As described above, the waste heat generating device 100, 200 can be used to recover the enormous amount of waste heat discarded through the high-level nuclear waste to generate electricity.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it is within the scope of the present invention.

12; Nuclear waste storage container 20; Thermoelectric devices
22; Hot junction 24; Cold junction
26; Thermoelectric elements 28; Lead wire
30; Radiation shielding member 40; Heat transfer member
50, 52; Insulation 100, 200; Waste heat generator

Claims (14)

A nuclear waste storage container adapted to receive nuclear waste and extending in one direction,
A thermoelectric device surrounding at least one side of the nuclear waste storage container, and
And a radioactive shield member surrounding the thermoelectric device. The method of claim 1,
And the thermoelectric device includes lead, the thermoelectric device primarily shields radiation emitted from the nuclear waste, and the radiation shielding member shields the radiation secondary. The method of claim 1,
The thermoelectric device,
High temperature junction in contact with the nuclear waste storage container receives heat;
A low temperature junction in contact with the radioactive shielding member, and
Waste heat generating apparatus comprising a plurality of thermoelectric elements connected between the high temperature junction and the low temperature junction. The method of claim 3,
An insulator in contact with the upper and lower surfaces of the nuclear waste storage container adjacent to the side of the nuclear waste storage container, and
A pair of lead wires penetrating the top surface insulation
More,
And the pair of lead wires are respectively connected to the high temperature junction and the low temperature junction. The method of claim 4, wherein
The heat insulator seals the waste heat generating device to block the waste heat generating device from the outside thereof. The method of claim 3,
The thermoelectric element is selected from the group consisting of bismuth-tellurium (Bi-Te) -based, lead-tellurium (Pb-Te) -based, silicon-germanium (Si-Ge) -based and ferrosilicon (Fe-Si) -based alloys. Waste heat generator comprising at least one element. The method of claim 6,
The thermoelectric element is a waste heat generator comprising the lead. The method of claim 7, wherein
The amount of lead is 30wt% to 70wt% waste heat generator. The method of claim 3,
And the nuclear waste storage container includes a plurality of side surfaces, and at least one of the plurality of side surfaces adjacent to each other is perpendicular to each other. 10. The method of claim 9,
And the thermoelectric elements are spaced apart from each other, and the thermoelectric elements have substantially the same length. The method of claim 5,
The temperature difference between the high temperature junction and the low temperature junction is 400 ℃ to 600 ℃ waste heat generator. The method of claim 1,
The at least one side has a curvature of waste heat generating device. The method of claim 1,
And a heat transfer member positioned between the thermoelectric device and the radioactive shielding member and in contact with the thermoelectric device and the radioactive shielding member. The method of claim 13,
The heat transfer member may include a thermal interface material (TIM), a thermal grease, a thermal adhesive epoxy bond, a thermally conductive silicone pad, a thermally conductive adhesive tape, and a graphite sheet. Waste heat generator comprising at least one element selected from the group consisting of Graphite Sheet.

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