Novel radioactive animal treatment process

Abstract

The invention provides a novel radioactive animal disposal process, and relates to the technical field of radioactive disposal, and the novel radioactive animal disposal process comprises the following steps: S1, classification and crushing treatment: animal carcasses of different types and sizes are separated, and the animal carcasses are decomposed into small blocks through the crushing treatment; and S2, steam reforming treatment: putting the pretreated animal carcass fragments into a closed steam reforming reactor. High-temperature and high-pressure steam is generated through the steam generator and is introduced into the reactor, the traditional treatment method possibly needs to occupy a large amount of space for burying or long-time incineration treatment, and the steam reforming technology can quickly convert corpses into gaseous products, so that the occupation of land resources is reduced, and the treatment time is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of radioactive disposal, and particularly to a new radioactive animal disposal process. Background Art

[0002] Due to some nuclear power radioactive accidents, a large number of radioactive animals have emerged. At the same time, during the development and application of radioactive pharmaceuticals, a large number of animal carcasses (such as goats, chickens, mice, etc.) are usually generated. Currently, these animal carcasses are temporarily stored in a frozen state. The animal carcasses contain a large amount of C-14 nuclide and belong to radioactive waste. These radioactive animals have posed a huge potential safety hazard to the environment and maintenance costs, and there is an urgent need for harmless disposal.

[0003] At present, radioactive animal disposal technologies are constantly evolving, but there are still multiple technologies coexisting, each with its own advantages and disadvantages. For example, in the initial stage, simple burial was used for radioactive wild boars in Fukushima. Later, due to the risk of secondary pollution of soil and groundwater, incineration became the main method. However, the number of incinerators that can effectively filter radioactive particles is insufficient and the cost is high. Moreover, traditional incineration processes are difficult to meet environmental protection standards. The flue gas generated contains secondary pollutants such as dust, acidic gases, and dioxins, and it is also quite difficult to treat the radioactive nuclide C-14. Summary of the Invention

[0004] The purpose of the present invention is to solve the deficiencies in the prior art and propose a new radioactive animal disposal process.

[0005] To achieve the above purpose, the present invention adopts the following technical scheme: A new radioactive animal disposal process, including the following steps: S1: Classification and crushing treatment: Separate animal carcasses of different species and sizes, and the crushing treatment is to decompose the animal carcasses into smaller pieces;

[0006] S2: Steam reforming treatment: Put the pretreated animal carcass pieces into a closed steam reforming reactor. Generate high-temperature and high-pressure steam through a steam generator and introduce it into the reactor;

[0007] S3: Organic matter decomposition: In the reactor, the proteins in the animal carcasses undergo denaturation and hydrolysis to generate products such as amino acids; fats are hydrolyzed into glycerol and fatty acids, and then further oxidized and decomposed; carbohydrates are decomposed into monosaccharides such as glucose, and then further decomposed into carbon dioxide and water. At the same time, the cell structure is destroyed and pathogenic microorganisms are killed to achieve harmless treatment;

[0008] S4: Catalytic treatment, add a catalyst to the reactor, using a nickel-based catalyst or a noble metal catalyst;

[0009] S5: Solid-Liquid Separation: After a period of steam treatment, most of the organic matter in the animal carcasses has been decomposed and converted. At this point, the solid-liquid separators inside and outside the reactor are used for separation. The reduced solid waste is directly barreled and sent to the next cement curing line.

[0010] S6: Liquid treatment: The liquid portion mainly includes hydrolysis products of various organic substances, inorganic salts, and water, etc., which also contains a small amount of pollutants such as nitrogen and phosphorus. This portion of the liquid is directly sent back to the steam reforming reactor, where the high temperature inside the reactor is used to evaporate the water. The generated salt solid waste is also barreled and sent to the cement curing line;

[0011] S7: Waste Gas Treatment: The steam reforming process generates some waste gas. The waste gas first passes through a condenser to cool the water vapor in it and condense it into water for recycling or wastewater treatment. The remaining gas passes through waste gas purification devices such as adsorption and biological deodorization to remove odors and harmful gases, and is discharged into the atmosphere after meeting the waste gas standards.

[0012] S8: Adsorption treatment: In the adsorption device during the waste treatment process, catechin is used as an adsorbent. When C14 exists in the form of carbon dioxide, the phenolic hydroxyl group of catechin may form hydrogen bonds with carbon dioxide molecules, thereby adsorbing it. For C14 existing in the form of carbonates, the functional group of catechin may form complexes with metal ions (such as calcium ions, if the carbonate is calcium carbonate), thereby indirectly adsorbing compounds containing C14;

[0013] S9: Waste purification treatment: The flue gas after adsorption passes through the waste purification device (such as deodorization, etc.), and then passes through the induced draft fan to meet the emission standards, thus completing this process.

[0014] Preferably, the steam temperature in S2 is controlled at 180-230° C. and the pressure is controlled at 5-10 atmospheres.

[0015] Preferably, the block weight of S1 is 1 to 2 kg.

[0016] Preferably, the solid portion of S5 is mainly undecomposed bones and hair residues, and the liquid portion includes hydrolysis products of various organic substances, inorganic salts and water.

[0017] Preferably, the exhaust gas from S7 contains water vapor, carbon dioxide, a small amount of ammonia and some organic gases with odor.

[0018] Compared with the prior art, the advantages and positive effects of the present invention are:

[0019] 1. In the present invention, the steam reforming technology has high processing capacity and can convert a large amount of organic substances in animal carcasses into gas in a relatively short time, greatly reducing the volume of the carcasses. This is very beneficial for dealing with a large number of radioactive animal carcasses and can reduce the difficulty and cost of subsequent processing and disposal. For example, for a large number of animal carcasses in animal farms contaminated by nuclear accidents or radioactive substance leaks, traditional processing methods may require a large amount of space for burial or long-term incineration, while the steam reforming technology can quickly convert these carcasses into gaseous products, reducing the occupation of land resources and processing time.

[0020] 2. Compared with the incineration method, the content of pollutants in the waste gas generated during the processing of the steam reforming technology is relatively low. A large amount of harmful gases such as nitrogen oxides and sulfur dioxide, as well as radioactive aerosols, may be generated during the incineration process, while mainly carbon dioxide, hydrogen and other relatively clean gases are generated during the steam reforming process. And through an appropriate waste gas adsorption treatment system, the emissions of harmful gases and radioactive substances can be further reduced, resulting in less environmental pollution.

[0021] 3. The steam reforming technology has a good radioactive substance fixation effect: Research shows that through reasonable selection of catalysts and reaction conditions, steam reforming can fix most radioactive substances on the solid residue or the surface of the catalyst. For example, for some radioactive metal ions, they may undergo chemical reactions with certain components in the catalyst to form insoluble compounds and thus be fixed. This can effectively reduce the diffusion risk of radioactive substances in the environment and reduce the pollution to the surrounding environment and ecosystem.

[0022] 4. During the steam reforming process, part of the volatile radioactive nuclides (such as C14) will be discharged with the gas. We can effectively absorb this part of the nuclides by selecting a highly efficient adsorbent (catechin), making the radioactive emissions meet the standards, because radioactive animals contain a large amount of C-14 with an activity of about 0.03 mCi / kg (1.11×106 Bq / kg). The catechin we use has unique advantages in the adsorption of C14. For example, compared with traditional adsorption materials such as activated carbon and filter cotton, the functional groups of catechin are more abundant and its adsorption of C14 is more specific. Activated carbon mainly adsorbs various substances through physical adsorption and has poor selectivity, while catechin can more specifically adsorb C14 through chemical action. At the same time, compared with traditional adsorption, catechin can be adsorbed and regenerated through simple physical or chemical methods, and its adsorption process is relatively simple and does not require a complex regeneration process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure is a flowchart of a novel radioactive animal disposal process proposed by the present invention. Detailed implementation manners

[0024] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0025] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, in the description of the present invention, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0026] Please refer to Figure 1 , the present invention provides a new type of radioactive animal disposal process, including the following steps: S1: Classification and crushing treatment: Separate animal carcasses of different types and sizes, and the crushing treatment is to decompose the animal carcasses into smaller blocks;

[0027] S2: Steam reforming treatment: Put the pretreated animal carcass fragments into a closed steam reforming reactor. Generate high-temperature and high-pressure steam through a steam generator and introduce it into the reactor;

[0028] S3: Organic matter decomposition: In the reactor, the proteins in the animal carcasses denature and hydrolyze to generate products such as amino acids; fats are hydrolyzed into glycerol and fatty acids, and then further oxidized and decomposed; carbohydrates are decomposed into monosaccharides such as glucose, and then further decomposed into carbon dioxide and water. At the same time, the cell structure is destroyed and pathogenic microorganisms are killed to achieve harmless treatment;

[0029] S4: Catalytic treatment, add a catalyst to the reactor, use a nickel-based catalyst or a noble metal catalyst;

[0030] S5: Solid-liquid separation treatment: After a period of steam treatment, most of the organic matter in the animal carcasses has been decomposed and transformed. At this time, separation is carried out through the solid-liquid separator inside and outside the reactor, and the volume-reduced solid waste is directly put into barrels and sent to the next cement solidification line;

[0031] S6: Liquid treatment: The liquid portion mainly includes hydrolysis products of various organic substances, inorganic salts, and water, etc., which also contains a small amount of pollutants such as nitrogen and phosphorus. This portion of the liquid is directly sent back to the steam reforming reactor, where the high temperature inside the reactor is used to evaporate the water. The generated salt solid waste is also barreled and sent to the cement curing line;

[0032] S7: Waste Gas Treatment: The steam reforming process generates some waste gas. The waste gas first passes through a condenser to cool the water vapor in it and condense it into water for recycling or wastewater treatment. The remaining gas passes through waste gas purification devices such as adsorption and biological deodorization to remove odors and harmful gases, and is discharged into the atmosphere after meeting the waste gas standards.

[0033] S8: Adsorption treatment: In the adsorption device during the waste treatment process, catechin is used as an adsorbent. When C14 exists in the form of carbon dioxide, the phenolic hydroxyl group of catechin may form hydrogen bonds with carbon dioxide molecules, thereby adsorbing it. For C14 existing in the form of carbonates, the functional group of catechin may form complexes with metal ions (such as calcium ions, if the carbonate is calcium carbonate), thereby indirectly adsorbing compounds containing C14;

[0034] S9: Waste purification treatment: The flue gas after adsorption passes through the waste purification device (such as deodorization, etc.), and then passes through the induced draft fan to meet the emission standards, thus completing this process.

[0035] The steam temperature in S2 is controlled at 180-230°C and the pressure is 5-10 atmospheres.

[0036] The block weight of S1 is 1 to 2 kg.

[0037] The solid part of S5 is mainly composed of incompletely decomposed bones and hair residues, while the liquid part contains hydrolysis products of various organic substances, inorganic salts and water.

[0038] The exhaust gas of S7 contains water vapor, carbon dioxide, a small amount of ammonia and some organic gases with odor.

[0039] The steam reforming technology of this invention boasts highly efficient processing capabilities, converting large amounts of organic matter from animal carcasses into gas in a relatively short period of time, significantly reducing the volume of the carcasses. This is highly advantageous for handling large numbers of radioactive animal carcasses, reducing the difficulty and cost of subsequent processing and disposal. For example, for large numbers of animal carcasses in animal farms contaminated by nuclear accidents or radioactive material leaks, traditional methods may require extensive burial or lengthy incineration processes, requiring significant space. However, steam reforming technology can rapidly convert these carcasses into gaseous products, reducing land use and processing time.

[0040] Compared with the incineration method, the pollutants in the waste gas generated during the steam reforming process are relatively low. During incineration, a large amount of harmful gases such as nitrogen oxides and sulfur dioxide, as well as radioactive aerosols, may be generated. While during the steam reforming process, the main gases generated are relatively clean gases such as carbon dioxide and hydrogen. Moreover, through an appropriate waste gas adsorption treatment system, the emissions of harmful gases and radioactive substances can be further reduced, resulting in less environmental pollution.

[0041] The steam reforming technology has a good effect on fixing radioactive substances: Research shows that by reasonably selecting catalysts and reaction conditions, steam reforming can fix most radioactive substances on the surface of solid residues or catalysts. For example, for some radioactive metal ions, they may undergo chemical reactions with certain components in the catalyst to form insoluble compounds, thereby being fixed. This can effectively reduce the diffusion risk of radioactive substances in the environment and reduce the pollution of the surrounding environment and ecosystem.

[0042] During the steam reforming process, some volatile radionuclides (such as C14) will be discharged with the gas. For this part of the radionuclides, we can effectively absorb them by selecting a highly efficient adsorbent (catechins) to meet the radioactive emission standards.

[0043] Because radioactive animals contain a large amount of C-14, with an activity of about 0.03 mCi / kg (1.11×106 Bq / kg). The catechins we use have unique advantages in adsorbing C14. For example, compared with traditional adsorption materials such as activated carbon and filter cotton, catechins have richer functional groups and more specific adsorption of C14. Activated carbon mainly adsorbs various substances through physical adsorption, with poor selectivity, while catechins can adsorb C14 more specifically through chemical action. At the same time, compared with traditional adsorption, catechins can be adsorbed and regenerated through simple physical or chemical methods, and its adsorption process is relatively simple and does not require a complex regeneration process.

[0044] The above are only the preferred embodiments of the present invention and do not limit the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A novel radioactive animal disposal process, characterized in that, The following steps are involved: S1: Sorting and crushing: Separate animal carcasses of different types and sizes. Crushing is to break down animal carcasses into smaller pieces. S2: Steam reforming treatment: The pre-treated animal carcass fragments are placed in a sealed steam reforming reactor. A steam generator generates high-temperature and high-pressure steam, which is then passed into the reactor. S3: Decomposition of organic matter: In the reactor, the protein in the animal carcasses is denatured and hydrolyzed to produce products such as amino acids; fat is hydrolyzed into glycerol and fatty acids, and then further oxidized and decomposed; carbohydrates are decomposed into monosaccharides such as glucose, and then further decomposed into carbon dioxide and water. At the same time, the cell structure is destroyed and pathogenic microorganisms are killed, achieving harmless treatment; S4: catalytic treatment, adding a catalyst into the reactor, using a nickel-based catalyst or a precious metal catalyst; S5: Solid-Liquid Separation: After a period of steam treatment, most of the organic matter in the animal carcasses has been decomposed and converted. At this point, the solid-liquid separators inside and outside the reactor are used for separation. The reduced solid waste is directly barreled and sent to the next cement curing line. S6: Liquid treatment: The liquid portion mainly includes hydrolysis products of various organic substances, inorganic salts, and water, etc., which also contains a small amount of pollutants such as nitrogen and phosphorus. This portion of the liquid is directly sent back to the steam reforming reactor, where the high temperature inside the reactor is used to evaporate the water. The generated salt solid waste is also barreled and sent to the cement curing line; S7: Waste Gas Treatment: The steam reforming process generates some waste gas. The waste gas first passes through a condenser to cool the water vapor in it and condense it into water for recycling or wastewater treatment. The remaining gas passes through waste gas purification devices such as adsorption and biological deodorization to remove odors and harmful gases, and is discharged into the atmosphere after meeting the waste gas standards. S8: Adsorption treatment: In the adsorption device during the waste treatment process, catechin is used as an adsorbent. When C14 exists in the form of carbon dioxide, the phenolic hydroxyl group of catechin may form hydrogen bonds with carbon dioxide molecules, thereby adsorbing it. For C14 existing in the form of carbonates, the functional group of catechin may form complexes with metal ions (such as calcium ions, if the carbonate is calcium carbonate), thereby indirectly adsorbing compounds containing C14; S9: Waste purification treatment: The flue gas after adsorption passes through the waste purification device (such as deodorization, etc.), and then passes through the induced draft fan to meet the emission standards, thus completing this process.

2. The novel radioactive animal disposal process according to claim 1, wherein: The steam temperature in S2 is controlled at 180-230° C., and the pressure is controlled at 5-10 atmospheres.

3. The novel radioactive animal disposal process according to claim 1, characterized in that: The block weight of the S1 is 1 to 2 kg.

4. The novel radioactive animal disposal process according to claim 1, characterized in that: The solid part of S5 is mainly undecomposed bones and hair residues, and the liquid part includes hydrolysis products of various organic substances, inorganic salts and water.

5. The novel radioactive animal disposal process according to claim 1, characterized in that: The exhaust gas from S7 contains water vapor, carbon dioxide, a small amount of ammonia and some organic gases with odor.

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