Radioactive solid waste compression method and overpressure machine

Abstract

The invention discloses a radioactive solid waste compression method which comprises the following steps: before compression, filling a compression cavity where a container is located with set gas so as to discharge air in the compression cavity; wherein the radioactive solid waste is placed in the container; compression is started, and in the compression process, the compression cavity is continuously filled with the set gas till compression is completed; the set gas is non-combustible and non-combustion-supporting gas. According to the compression method for the radioactive solid waste, spontaneous combustion of the radioactive solid waste can be effectively restrained in the compression process, the operation safety is improved, and waste leakage is avoided. The invention further provides a radioactive solid waste overpressure machine.

Description

Technical Field

[0001] The invention belongs to the technical field of waste treatment, and in particular relates to a compression method for radioactive solid waste and a super press. Background Art

[0002] In the reprocessing facility, the spent fuel assembly is cut into short sections, then dissolved and cleaned, and the remaining waste cladding needs to be stored and disposed of. In order to reduce the volume of waste to be disposed of, the cleaned waste cladding is filled into a container, the waste in the container is dried, and the container is sent to the super press for compression and volume reduction.

[0003] Since the waste cladding is made of zirconium alloy, the zirconium cladding is brittle after irradiation and has a high temperature after drying. During the compression process, debris will be produced under the action of mechanical force, and heat will be generated, causing further temperature rise.

[0004] Zirconium cladding debris is prone to spontaneous combustion at high temperatures, and the traditional compression method of metal radioactive solid waste does not take effective measures to prevent the solid waste from spontaneous combustion. Currently, there is a method of filling the container with inert gas, but spontaneous combustion cannot be avoided during the compression process. Summary of the invention

[0005] The inventors have found that the reason why the current method cannot avoid the spontaneous combustion of waste during the compression process is that the container often collapses during the compression process. At this time, the debris, powder, etc. overflow into the compression environment, resulting in the possibility of spontaneous combustion when mixed with the external air. In addition, once more debris and powder are generated during the waste compression process, more powder overflows and mixes with the air when it collapses, or air enters the container with more powder, and there is a probability of more serious accidents than spontaneous combustion (such as explosion). However, the current improvement direction focuses on the prevention of spontaneous combustion inside the container, and does not take into account the changes in the external environment; in addition, the compression is performed using a cylindrical structure as a mold, which is not only limited in space, but also changes in the space occupied by the container in the mold as it is compressed. The layout of the space to prevent spontaneous combustion means will inevitably damage the mold structure, making it difficult for technicians in this field to associate environmental changes.

[0006] Accordingly, the technical problem to be solved by the present invention is to provide a radioactive solid waste compression method in view of the above-mentioned deficiencies in the prior art, which can effectively inhibit the spontaneous combustion of radioactive solid waste during the compression process, improve the safety of the operation, and avoid waste leakage. The present invention also provides a radioactive solid waste super press.

[0007] The present invention provides a method for compressing radioactive solid waste, comprising the following steps: before compression, filling a set gas into a compression cavity where a container is located to discharge air in the compression cavity; wherein the radioactive solid waste is placed in the container;

[0008] Start compression, and during the compression process, keep filling the compression chamber with the set gas until the compression is completed;

[0009] The set gas is a non-flammable and non-combustion-supporting gas.

[0010] Furthermore, the method further comprises the following steps:

[0011] During the compression process, the gas in the compression chamber is extracted;

[0012] After the compression is completed, continue to extract the gas in the compression chamber for a set time.

[0013] Furthermore, during the compression process, a set gas is filled into the compression chamber with a first gas volume, and the gas in the compression chamber is extracted with a second gas volume, and the first gas volume is smaller than the second gas volume, so that a negative pressure is maintained in the compression chamber.

[0014] Furthermore, before the set gas is charged into the compression chamber where the container is located, the method further comprises the following steps: charging the set gas into the container containing the solid waste to discharge the air in the container; and then placing the container in the compression chamber.

[0015] The present invention also provides a radioactive solid waste super pressurizer, comprising: a compression component, having a compression chamber, for compressing a container placed in the compression chamber, wherein radioactive fixed waste is placed in the container; an inflation component, connected to the compression chamber, for filling the compression chamber with a set gas before and during compression; the set gas is a non-flammable and non-combustible gas.

[0016] Furthermore, the compression assembly includes an anvil, a pressing head assembly and a mold. The mold is cylindrical, with a bottom opening nested and connected to the anvil. The container is placed on the anvil, and the pressing head assembly extends into the mold through the top opening of the mold, thereby forming a compression cavity together with the mold and the anvil.

[0017] Furthermore, a gas nozzle is provided at the end of the pressing head assembly located in the mold, and the gas nozzle is connected to the inflation assembly so that when the pressing head assembly presses the container toward the anvil, the set gas filled into the inflation assembly is always kept within a set distance range from the container.

[0018] Furthermore, the pressure head assembly includes a pressure rod, a connecting rod and a pressure head. A vertical through hole is opened in the pressure rod, and a first air hole and a second air hole are respectively opened on the side walls at the upper and lower ends. The first air hole and the second air hole are both connected to the through hole. The diameter of the connecting rod is smaller than the inner diameter of the through hole. The connecting rod is inserted into the through hole, and the bottom end is connected to the pressure head to tighten and fix the pressure head to the bottom of the pressure rod. The inflation assembly is connected to the first air hole, and the first air hole, the through hole and the second air hole are used as flow channels. The second air hole is used as a gas nozzle to fill the set gas into the compression chamber.

[0019] Furthermore, the super compressor also includes an exhaust component, which is connected to the compression chamber and is used to extract gas in the compression chamber during the compression process and continue to extract gas in the compression chamber for a set time after the compression is completed.

[0020] Furthermore, the inner diameter of the top opening of the mold is larger than the outer diameter of the pressure head assembly, and the vacuum assembly includes a vacuum plate, which is in a circular ring shape and is arranged at the edge of the top opening of the mold to extract the gas in the compression cavity through the gap between the top opening of the mold and the pressure head assembly.

[0021] Furthermore, a groove is provided on the inner ring surface of the vacuum disk so that the cross section of the vacuum disk is a horizontal U-shaped structure, and air holes are provided on the side of the groove so that the extracted gas enters the groove from the compression cavity and flows out from the air holes.

[0022] Furthermore, the super press also includes a control unit, and the pressure head assembly is provided with a first sensing member and a second sensing member, the first sensing member is used to sense whether the pressure head assembly contacts the container, and the second sensing member is used to sense whether the container is compressed; the control unit is electrically connected to the inflation assembly, the first sensing member, the second sensing member and the pressure head assembly respectively, and is used to control the pressure head assembly to stop when the first sensing member senses that the pressure head assembly contacts the container, and control the inflation assembly to start at the same time; and, control the pressure head assembly to start compressing the container after the inflation assembly is turned on for a set period of time; and, control the inflation assembly to close after the second sensing member senses that the container compression is completed.

[0023] The radioactive solid waste compression method of the present invention completely discharges the air in the cavity by filling the compression cavity with a non-combustible and non-combustible set gas before compression, so that the set gas wraps the entire container to form an external inert environment, and during the entire compression process, the set gas is kept filled into the compression cavity. Therefore, when the container is crushed, after the debris and powder overflow into the compression cavity, they are still in an inert environment to avoid spontaneous combustion caused by mixing with air. It can be seen that the present method can effectively reduce, control or even completely eliminate the risk of spontaneous combustion of solid waste with a tendency to spontaneous combustion during the compression process, thereby improving operational safety and avoiding more serious accidents caused by spontaneous combustion of waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of a radioactive solid waste super press in Example 2 of the present invention.

[0025] In the figure: 1. anvil; 2. pressure head assembly; 21. pressure rod; 211. through hole; 212. first air hole; 213. second air hole; 22. connecting rod; 23. pressure head; 3. mold; 31. compression cavity; 4. inflation assembly; 41. first quick connector; 42. first hose; 5. exhaust assembly; 51. exhaust plate; 52. second quick connector; 53. second hose; 6. container; 7. solid waste. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "upper", "lower" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience and simplification of the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0028] In the description of the present invention, the terms “first”, “second” and “third” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connect", "set", "install", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0030] Example 1

[0031] The method for compressing radioactive solid waste in this embodiment comprises the following steps:

[0032] Before compression, a set gas is charged into the compression cavity where the container is located to discharge the air in the compression cavity; wherein the radioactive solid waste is placed in the container;

[0033] Start compression, and during the compression process, keep filling the compression chamber with the set gas until the compression is completed;

[0034] Set the gas to be non-flammable and non-combustible gas.

[0035] The radioactive solid waste compression method of the present embodiment completely expels the air in the cavity by filling the compression cavity with a non-combustible and non-combustible set gas before compression, so that the set gas wraps the entire container, forming an external inert environment, and during the entire compression process, the compression cavity is kept filled with the set gas. Therefore, when the container is crushed, after the debris and powder overflow into the compression cavity, they are still in an inert environment to avoid spontaneous combustion caused by mixing with air. It can be seen that the present method can effectively reduce, control or even completely eliminate the risk of spontaneous combustion of radioactive solid waste with a tendency to spontaneous combustion during the compression process, thereby improving operational safety and avoiding more serious accidents caused by spontaneous combustion of waste.

[0036] In this embodiment, the method further comprises the following steps:

[0037] During the compression process, the gas in the compression chamber is extracted;

[0038] After the compression is completed, the gas in the compression chamber is continuously extracted for a set time. In this embodiment, the set time is 5s to 10s, which can be specifically selected according to the volume of the compression chamber, the extraction speed, and the like.

[0039] Extracting the gas in the compression chamber can not only prevent the increase of air pressure in the compression chamber from affecting the compression process, but also cooperate with the inflation process to collect the powder and waste gas blown down by the set gas and overflowed from the container, and then discharge them to a designated location for centralized treatment to avoid waste leakage. At the same time, it can take away the heat generated in the compression process, further destroy the conditions for spontaneous combustion, and reduce the possibility of spontaneous combustion.

[0040] In this embodiment, during the compression process, a set gas is filled into the compression chamber with a first gas volume, and the gas in the compression chamber is extracted with a second gas volume. The first gas volume is smaller than the second gas volume, so that a negative pressure is maintained in the compression chamber. Among them, the first gas volume is 5L / s to 8L / s, and the second gas volume is 8L / s to 10L / s. This scheme in which the extraction volume is greater than the filling volume can effectively prevent the radioactive atmosphere from overflowing from the compression chamber and polluting the external environment. In this embodiment, before and during compression, a set gas is filled into the compression chamber at a first set pressure of 0.2Mpa to 0.5Mpa. This set pressure can ensure that the gas is quickly discharged before compression, and the gas in the compression chamber is extracted at a second set pressure of -0.1kPa to -0.2kPa during compression.

[0041] In this embodiment, before the set gas is filled into the compression chamber where the container is located, the method further includes the following steps: filling the container containing solid waste with the set gas to expel the air in the container; and then placing the container in the compression chamber. After filling, the set gas completely wraps the solid waste in the container to ensure that the solid waste is still in an inert environment during the compression process. This step can ensure that the dry solid waste in the container will not spontaneously combust even if it is further heated up under the action of mechanical force; at the same time, the inside and outside of the waste container maintain a consistent inert environment. The powder generated during the compression process has no chance to mix with air or other gases with different components, whether inside the container or overflowing into the compression chamber. Even if the internal and external environmental gases interact from the rupture, no serious accident will occur.

[0042] In this embodiment, the set gas filled into the container and the set gas filled into the compression chamber can be nitrogen and / or argon, and other inert gases can also be selected according to the type of radioactive solid waste.

[0043] The compression method generally adopts a super press as in Example 2, which includes an anvil 1, a mold 3 and a pressure head assembly 2 (including a pressure head 23, a main pressure rod, i.e., a pressure rod 21, and a connecting rod 22). The anvil 1, the mold 3 and the pressure head assembly 2 are arranged to form a compression cavity 31 located in the cylindrical mold 3 to accommodate the container 6 to be compressed. The solid waste 7 in the container 6 can be a metal such as a zirconium alloy or a zirconium cladding, so the container 6 can also be a compaction tank.

[0044] The overall process of the compression method of this embodiment can be further specifically described as the following steps:

[0045] ① Before compression:

[0046] Place the solid waste that needs to be compressed into a container;

[0047] Before the container is transported to the super compressor, a set gas is filled into the container (from the bottom of the container) to expel the air in the container; after the container is filled with the set gas, the set gas wraps the solid waste to ensure that the solid waste is in an inert environment during the compression process;

[0048] After the container is filled with the set gas, the container is transported to the anvil of the super press, so that the container is in place in the super press;

[0049] The mold of the super press is lowered to the lowest point so that the bottom opening of the mold is nested and connected to the anvil;

[0050] The main pressure rod (i.e., the pressure rod) of the super press drives the pressure head (i.e., the pressure head assembly as a whole) to descend, and stops when the lower end of the pressure head contacts the upper end of the container;

[0051] (Through the inflation assembly) fill the compression cavity formed by the mold, the pressure head assembly, and the anvil (where the inner diameter of the mold is several millimeters larger than the outer diameter of the container and the diameter of the pressure head assembly, and the diameter of the pressure head is slightly larger than the outer diameter of the container, thereby forming a cavity) with a set gas to expel the air in the compression cavity; this step allows the set gas to wrap the outside of the container, and together with the set gas in the container, ensures the safety of the waste compression process. The set gas enters from the first air hole 212 on the side of the upper part of the main pressure rod, goes down through the through hole 211 in the center of the main pressure rod, and flows out from the second air hole 213 on the side of the lower end of the main pressure rod to enter the compression cavity;

[0052] ②Start compression:

[0053] The main pressure rod drives the pressure head to continue to descend;

[0054] During the compression process, the set gas is continuously charged into the compression cavity, and the gas in the compression cavity is extracted (the exhaust device installed at the upper end of the mold is opened);

[0055] In this process, when the container is compressed to a set pressure (this set pressure is the pressure when the container ruptures after being compressed, which is determined according to the container's own conditions), the container may be crushed and ruptured, and the set gas inside the container will carry the possible powder to overflow into the compression chamber, and the powder can be purged by continuously filling the compression chamber with the set gas, and finally the powder and waste gas are discharged by exhaust and centrally processed, and the heat generated in the compression process is taken away at the same time;

[0056] ③After compression is completed:

[0057] Stop filling the compression chamber with the set gas, and continue to extract the gas in the compression chamber for 5s to 10s to discharge all the powder.

[0058] This embodiment can be said to provide a method for compressing solid waste with a tendency to spontaneous combustion, which can be applied to the treatment of irradiated metal solid waste in the nuclear industry, and is particularly suitable for metal solid waste containing zirconium alloys. This method for compressing solid waste with a tendency to spontaneous combustion is intended to reduce, control or even eliminate the risk of spontaneous combustion of solid waste with a tendency to spontaneous combustion during the compression process, and is particularly suitable for the compression and volume reduction of metal solid waste containing zirconium alloys.

[0059] Example 2

[0060] The radioactive solid waste super press of this embodiment can be used in the compression method of embodiment 1, and the super press comprises: a compression component, having a compression chamber 31, for compressing a container 6 placed in the compression chamber 31, and radioactive fixed waste 7 is placed in the container 6; an inflation component 4, connected to the compression chamber 31, for filling the compression chamber 31 with a set gas before and during compression; the set gas is a non-flammable and non-combustible gas.

[0061] Similarly, by filling the compression chamber 31 with a non-combustible and non-combustible set gas to completely expel the air in the chamber, the set gas wraps the entire container 6, forming an external inert environment, and during the entire compression process, the set gas is kept filled into the compression chamber 31. Therefore, when the container 6 is crushed, the debris and powder overflow into the compression chamber 31, and they are still in an inert environment to avoid spontaneous combustion caused by mixing with air. It can be seen that the risk of spontaneous combustion of solid waste with a tendency to spontaneous combustion during the compression process can be effectively reduced, controlled, or even completely eliminated, thereby improving operational safety and avoiding more serious accidents caused by spontaneous combustion of waste. Moreover, the solution for improving the environment in this embodiment is aimed at the compression chamber 31 that already exists in the original compression process. Not only does it not require changes to the original structure, but the inflation space is also relatively small, effectively reducing the cost of improvement.

[0062] In this embodiment, the compression assembly includes an anvil 1, a pressing head assembly 2 and a mold 3. The mold 3 is cylindrical, and the bottom opening is nested and connected to the anvil 1. The container 6 is placed on the anvil 1. The pressing head assembly 2 penetrates into the mold 3 through the top opening of the mold 3, thereby forming a compression cavity 31 together with the mold 3 and the anvil 1. During the compression process, the pressing head assembly 2 continuously presses downward in the direction of the anvil 1, so that the container 6 is pressed into a volume size that meets the requirements with the inner wall of the mold 3 as a mold.

[0063] In this embodiment, a gas nozzle is provided at the end of the ram assembly 2 located in the mold 3, and the gas nozzle is connected to the gas filling assembly 4, so that the set gas filled into the gas filling assembly 4 is always kept within the set distance range from the container 6 during the process of the ram assembly 2 pressing the container 6 toward the anvil 1. By setting the gas nozzle of the set gas on the ram assembly 2, it does not cause any damage to the mold 3, ensuring the service life of the equipment, and avoiding the leakage of compressed waste gas and dust. More importantly, the position of the gas nozzle is cleverly set, and can change with the spatial position occupied by the container 6 in the compression chamber 31. This follow-up can ensure that the gas nozzle always follows the container 6, and the overflow, debris, and dust of the container 6 are blown away in time, and the temperature rise caused by the compression process can also be effectively reduced.

[0064] In this embodiment, the pressure head assembly 2 includes a pressure rod 21, a connecting rod 22 and a pressure head 23. A vertical through hole 211 is opened in the pressure rod 21, and a first air hole 212 and a second air hole 213 are respectively opened on the side walls at the upper and lower ends. The first air hole 212 and the second air hole 213 are both connected to the through hole 211. The diameter of the connecting rod 22 is smaller than the inner diameter of the through hole 211. The connecting rod 22 is penetrated in the through hole 211, and the bottom end is connected to the pressure head 23 to tighten and fix the pressure head 23 at the bottom of the pressure rod 21. The inflation assembly 4 is connected to the first air hole 212, and the first air hole 212, the through hole 211 and the second air hole 213 are used as flow channels. The second air hole 213 is used as a gas nozzle to fill the set gas into the compression chamber 31.

[0065] It can be seen that the inflatable component 4 uses the existing through hole 211 as a flow channel, which reduces the improvement cost, and can also make the inflatable component 4 body away from the compression chamber 31 to avoid position interference, reduce the difficulty of component space layout, and facilitate the maintenance of the inflatable component 4 itself. The inflatable component 4 includes a first quick connector 41 and a first hose 42. One end of the first quick connector 41 can be quickly connected to the first air hole 212, and the other end can be connected to the air supply source through the first hose 42 to supply the set gas.

[0066] The through hole 211 is coaxial with the pressure rod 21. The first air hole 212 and the second air hole 213 can be horizontally arranged holes that pass through the through hole 211. There are two second air holes 213 (more can be provided as needed in other embodiments), and the two second air holes 213 are symmetrically distributed relative to the axial direction of the pressure rod 21.

[0067] In this embodiment, the radioactive solid waste super pressurizer also includes an exhaust component 5, which is connected to the compression chamber 31 and is used to extract the gas in the compression chamber 31 during the compression process, and continue to extract the gas in the compression chamber 31 for a set time after the compression is completed. The set time is 5s to 10s.

[0068] Extracting the gas in the compression chamber 31 can not only prevent the increase of air pressure in the compression chamber 31 from affecting the compression process, but also cooperate with the inflation process to collect the powder and waste gas blown down by the set gas and overflowed from the container, and then discharge them to a designated location for centralized treatment to avoid waste leakage. At the same time, it can take away the heat generated in the compression process, further destroy the spontaneous combustion conditions, and reduce the possibility of spontaneous combustion.

[0069] In this embodiment, the inner diameter of the top opening of the mold 3 is larger than the outer diameter of the pressure head assembly 2, and the air extraction assembly 5 includes an air extraction plate 51, which is annular and arranged at the edge of the top opening of the mold 3, and extracts the gas in the compression cavity 31 through the gap between the top opening of the mold 3 and the pressure head assembly 2. This setting position does not block the gap between the mold 3 and the pressure head assembly 2, so that the air can be discharged during the inflation of the compression cavity 31 before compression, and the gas overflowing from the compression cavity 31 can be extracted in time during the air extraction.

[0070] In this embodiment, a groove is provided on the inner surface of the vacuum plate 51, so that the cross section of the vacuum plate 51 is a horizontal U-shaped structure, and air holes are provided on the side of the groove, so that the extracted gas enters the groove from the compression chamber 31 and flows out from the air holes. There are multiple air holes, which are evenly distributed on the groove (they can be set on the upper side, lower side or bottom side of the groove). The vacuum plate 51 is connected to the vacuum equipment through the second quick connector 52 and the second hose 53 in turn, and finally connected to the subsequent waste treatment area to discharge the extracted gas waste to the subsequent treatment process. The U-shaped groove structure with side openings is a semi-enclosed structure, which not only connects the gap of the compression chamber to the outside through the opening, but also has an inclusion area to contain gas, so that the hose 53 can connect to the inclusion area to extract gas, providing structural convenience for vacuuming.

[0071] The radioactive solid waste super pressurizer of this embodiment may also be additionally provided with a container filling mechanism and a conveying mechanism. The conveying mechanism is arranged between the container filling mechanism and the anvil 1. The container filling mechanism is used to fill the container 6 with a set gas. After filling, the conveying mechanism conveys the container 6 to the anvil 1.

[0072] In this embodiment, the radioactive solid waste super pressurizer also includes a control unit. A first sensor and a second sensor are provided on the pressure head assembly 2. The first sensor is used to sense whether the pressure head assembly 2 contacts the container 6, and the second sensor is used to sense whether the container 6 has been compressed. The control unit is electrically connected to the inflation assembly 4, the first sensor, the second sensor and the pressure head assembly 2, respectively, and is used to control the pressure head assembly 2 to stop when the first sensor senses that the pressure head assembly 2 contacts the container 6, and to control the inflation assembly 4 to start at the same time; and, after the inflation assembly 4 is turned on for a set period of time, control the pressure head assembly 2 to start compressing the container 6; and, after the second sensor senses that the compression of the container 6 is completed, control the inflation assembly 4 to close.

[0073] The first sensing element may be a contact sensor or other sensing component disposed on the bottom surface of the pressure head 23, and the node where the bottom surface of the pressure head 23 contacts the top surface of the container 6 is used to divide the time before compression and the beginning of compression. The second sensing element may be a displacement sensor disposed on the pressure head 23 or the pressure rod 21, or other sensing components capable of sensing the amount of compression of the container 6, to confirm whether the container 6 has completed compression. Before compression, the inflation component 4 is opened for a set time to fill the compression chamber 31. The set time can be determined according to the set gas flow rate, the size of the compression chamber 31, the size of the container volume, etc., and can be appropriately adjusted according to actual conditions.

[0074] The super press of this embodiment comprises an anvil 1, a mold 3 and a pressure head assembly 2 (including a pressure head 23, a main pressure rod, i.e., a pressure rod 21, and a connecting rod 22), wherein the anvil 1, the mold 3 and the pressure head assembly 2 are arranged to form a compression cavity 31 located in the cylindrical mold 3, for accommodating a container 6 to be compressed. The solid waste 7 in the container 6 can be a metal such as a zirconium alloy or a zirconium (waste) cladding, so the container 6 can also be a compaction tank, which can be used for the treatment of spent fuel assemblies.

[0075] The anvil 1 is fixed and is located directly below the pressure head assembly 2 and the mold 3. A through hole 211 is provided at the center of the main pressure rod 21. The connecting rod 22 passes through the center of the main pressure rod 21, and the lower end is connected to the inner hole of the pressure head 23 to tighten the pressure head 23; the diameter of the connecting rod 22 is smaller than the diameter of the through hole 211. The upper end (center) of the pressure head 23 is provided with a protruding portion with an outer conical surface, and the outer conical surface cooperates with the inner conical surface provided at the lower end of the through hole 211 of the main pressure rod 21. The mold 3 is cylindrical, and a through hole (or inner cavity) is provided in the center. The inner diameter of the hole is several millimeters larger than the diameter of the pressure head 23 and the compaction tank. The lower end surface of the hole is a conical surface, which matches the upper end conical surface of the anvil 1 (located at the outer edge of the upper end of the anvil 1), and can play a guiding role when the mold 3 falls.

[0076] A horizontal gas passage (first air hole 212) is opened at the upper end of the main pressure rod 21, one end of which is connected to the external first quick connector 41, and then connected to the first hose 42, and the other end is connected to the central through hole 211 of the main pressure rod 21; two horizontal symmetrical gas passages (second air holes 213) are opened radially at the lower end of the main pressure rod 21, which are connected to the central through hole 211 of the main pressure rod 21, thereby forming an inflation passage.

[0077] An annular groove may be provided at the upper end of the mold 3, in which an exhaust plate 51 is fixed. The exhaust plate 51 is a U-shaped circular ring. The U-shaped groove is located at the inner circle of the exhaust plate 51, and a vent hole is opened on the side wall, which is connected to the second quick connector 52 and then to the second hose 53, thereby forming an exhaust channel.

[0078] After the spent fuel assembly is sheared, short segments are produced. After dissolution and cleaning, the remaining waste cladding is filled into the compaction tank as solid waste 7, and then dried to remove the water in the waste cladding to prevent the water from being decomposed by radiation to produce hydrogen (to prevent hydrogen embrittlement of zirconium alloy) and oxygen (to prevent spontaneous combustion of zirconium alloy dust). After drying, it is sent to the super press and filled with set gas from the bottom of the compaction tank. After it is full, all the air in the compaction tank is discharged to ensure that the waste cladding is completely wrapped by the set gas, forming an internal inert environment to prevent the waste cladding from spontaneous combustion during the compression process.

[0079] When in use, the super compressor of this embodiment works as follows:

[0080] The mold 3, the pressure head 23, the main pressure rod 21, and the connecting rod 22 (i.e., the entire pressure head assembly 2) are placed at a high position, and then the compaction tank filled with waste shells is transported to the anvil 1 (at this time, the interior of the container 6 is filled with a set gas to exhaust the air, so it can also be said that the container 6 containing solid waste 7 and filled with a set gas is placed on the anvil 1). After the compaction tank and the anvil 1 are aligned, the mold 3 is stopped when it falls to the lowest point, and the conical surface of the lower opening of the mold 3 is nested and connected with the upper slope of the anvil 1. The main pressure rod 21 drives the pressure head 23 and the connecting rod 22 to fall together. When the lower end surface of the pressure head 23 contacts the upper end surface of the compaction tank, it stops falling. At this time, the gap between the anvil 1, the pressure head 23, the mold 3 and the compaction tank forms a cavity. Before the pressure head 23 continues to fall and pressurize, inert gas is introduced from the first hose 42, through the first quick connector 41, the first air hole 212, the through hole 211, and the second air hole 213, and finally enters the compression chamber 31. After being filled, the air in the compression chamber 31 is completely discharged, and the inert gas wraps the entire compaction tank to form an external inert environment, which further ensures the safety of the waste shell compression process.

[0081] The pressure head 23 continues to descend, applying pressure to the compaction tank to compress it. During the compression process, inert gas is continuously introduced into the compression chamber 31, and the vacuum assembly 5 is turned on at the same time. When the compaction tank is compressed beyond the threshold value, the compaction tank is crushed and ruptured. At this time, the inert gas in the compaction tank and the zirconium alloy dust generated during the compression process overflow into the compression chamber 31. The introduced inert gas can purge the dust to prevent it from scattering and accumulating in the compression chamber 31. The vacuum assembly 5 can discharge the dust-containing exhaust gas and the energy generated during the compression process through the vacuum plate 51, the second quick connector 52, and the second hose 53 to the exhaust gas treatment unit for centralized treatment. After the compression is completed, stop filling the compression chamber 31 with inert gas, continue to pump air, and stop pumping air after waiting for a period of time.

[0082] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for compressing radioactive solid waste, characterized in that: The following steps are involved: Before compression, a set gas is charged into the compression cavity where the container is located to discharge the air in the compression cavity; wherein the radioactive solid waste is placed in the container; Start compression, and during the compression process, continue to fill the compression chamber with the set gas until the compression is completed; The set gas is a non-flammable and non-combustion-supporting gas.

2. The method for compressing radioactive solid waste according to claim 1, characterized in that: The method further comprises the following steps: During the compression process, the gas in the compression chamber is extracted; After the compression is completed, continue to extract the gas in the compression chamber for a set time.

3. The method for compressing radioactive solid waste according to claim 2, characterized in that: During the compression process, a set gas is filled into the compression chamber with a first gas volume, and the gas in the compression chamber is extracted with a second gas volume. The first gas volume is smaller than the second gas volume, so that a negative pressure is maintained in the compression chamber.

4. The method for compressing radioactive solid waste according to claim 1, characterized in that: Before the setting gas is charged into the compression cavity where the container is located, the method further comprises the following steps: Filling a container containing solid waste with a set amount of gas to expel the air from the container; The container is then placed in the compression chamber.

5. A radioactive solid waste super press, characterized in that: include: A compression assembly having a compression chamber (31) for compressing a container (6) placed in the compression chamber (31), wherein radioactive fixed waste (7) is placed in the container (6); An air charging component (4) is communicated with the compression chamber (31) and is used to charge a set amount of gas into the compression chamber (31) before and during compression; The set gas is a non-flammable and non-combustion-supporting gas.

6. The radioactive solid waste super pressurizer according to claim 5, characterized in that: The compression assembly comprises an anvil (1), a pressing head assembly (2) and a mold (3); the mold (3) is cylindrical, with an opening at the bottom that is nested and connected to the anvil (1). The container (6) is placed on the cutting board (1). The pressing head assembly (2) penetrates into the mold (3) through the top opening of the mold (3), thereby forming a compression cavity (31) together with the mold (3) and the anvil (1).

7. The radioactive solid waste super pressurizer according to claim 6, characterized in that: The end of the pressure head assembly (2) located inside the mold (3) is provided with a gas nozzle. The gas nozzle is connected to the inflation component (4) so ​​that when the pressure head component (2) presses the container (6) toward the anvil (1), the set gas filled into the inflation component (4) is always kept within a set distance range from the container (6).

8. The radioactive solid waste super pressurizer according to claim 7, characterized in that: The pressure head assembly (2) comprises a pressure rod (21), a connecting rod (22) and a pressure head (23). A vertical through hole (211) is provided in the pressure rod (21), and a first air hole (212) and a second air hole (213) are respectively provided on the side walls at the upper and lower ends, and the first air hole (212) and the second air hole (213) are both connected to the through hole (211). The diameter of the connecting rod (22) is smaller than the inner diameter of the through hole (211), the connecting rod (22) is inserted into the through hole (211), and the bottom end is connected to the pressure head (23) so as to tighten and fix the pressure head (23) at the bottom of the pressure rod (21). The inflation component (4) is connected to the first air hole (212), and uses the first air hole (212), the through hole (211) and the second air hole (213) as flow channels, and the second air hole (213) as a gas nozzle to fill the set gas into the compression cavity (31).

9. The radioactive solid waste super pressurizer according to claim 6, characterized in that: It also includes an air extraction component (5), The gas extraction component (5) is in communication with the compression chamber (31) and is used to extract gas from the compression chamber (31) during the compression process, and to continue to extract gas from the compression chamber (31) for a set time after the compression is completed.

10. The radioactive solid waste super pressurizer according to claim 9, characterized in that: The inner diameter of the top opening of the mold (3) is larger than the outer diameter of the pressure head assembly (2). The vacuum assembly (5) comprises a vacuum plate (51) which is in the shape of a ring and is arranged at the edge of the top opening of the mold (3) to extract gas from the compression cavity (31) through the gap between the top opening of the mold (3) and the pressure head assembly (2).

11. The radioactive solid waste super pressurizer according to claim 10, characterized in that: A groove is provided on the inner surface of the air extraction plate (51), so that the cross section of the air extraction plate (51) is a horizontal U-shaped structure. An air hole is provided on the side of the groove so that the extracted gas enters the groove from the compression chamber (31) and flows out from the air hole.

12. The radioactive solid waste super pressurizer according to claim 6, characterized in that: Also includes a control unit, The pressure head assembly (2) is provided with a first sensing element and a second sensing element. The first sensing element is used to sense whether the pressure head assembly (2) contacts the container (6). The second sensing element is used to sense whether the container (6) has been compressed; The control unit is electrically connected to the inflation component (4), the first sensing element, the second sensing element and the pressure head component (2) respectively, and is used to control the pressure head component (2) to stop when the first sensing element senses that the pressure head component (2) contacts the container (6), and simultaneously control the inflation component (4) to start; and, after the inflation component (4) is turned on for a set period of time, controlling the pressure head component (2) to start compressing the container (6); And, after the second sensing element senses that the container (6) has been compressed, the inflation component (4) is controlled to close.

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