Method for reducing radioactive contaminated waste

Abstract

Provided herein is a method for reducing radioactively contaminated waste, comprising treating a radioactively contaminated surface, wherein the surface is treated with a surface treatment agent, treating a radioactively contaminated subsurface, wherein the subsurface is treated with a surface / subsurface treatment agent, consolidating the soil waste, employing real-time scanning technology to classify the waste, wherein the classification is based at least in part on a radioactive contamination threshold, segregating the classified waste based on the classification, and disposing of the waste via at least one of different disposal routes based at least in part on the classification.

Description

Background Art

[0001] (Cross - reference to related applications) This application claims priority based on a related application of U.S. Provisional Patent Application No. 16 / 871,703, filed on May 11, 2021, the entire disclosure of which is incorporated herein by reference in its entirety.

[0002] In nuclear facilities (such as nuclear power plants, research facilities, defense facilities, etc.) where radioactive substances are used and studied, radioactive contaminated waste can be generated. For example, radioactive contaminated waste may be generated during the operation or maintenance of a nuclear reactor, or during the decommissioning of a nuclear facility and / or its components. The disposal of radioactive contaminated waste is a major source of responsibility and cost related to the operation and decontamination of nuclear facilities.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The following summary is provided to facilitate an understanding of some of the innovative features specific to the embodiments of the present disclosure and is not intended as a complete description. Various aspects of the embodiments can be fully understood by comprehensively grasping the entire specification, claims, summary, and drawings.

[0004] This specification provides a method for reducing radioactive contaminated waste. The method includes a step of treating a radioactively contaminated surface, the step of treating the radioactively contaminated surface with a surface treatment agent, a step of treating the area under the radioactively contaminated surface, the step of treating the area under the radioactively contaminated surface with a surface / subsurface treatment agent, a step of aggregating soil waste, a step of adopting real - time scanning technology to at least partially classify the waste, the classification being based on a threshold of radioactive contamination, a step of classifying the classified waste based on the classification, and a step of disposing of the waste through at least one of different disposal routes based at least in part on the classification.

[0005] Also provided herein is a method for reducing radioactive waste. The method includes a step of treating a radioactively contaminated surface, the step of treating the radioactively contaminated surface with a surface treatment agent, a step of treating under the radioactively contaminated surface, the step of treating under the radioactively contaminated surface with a surface / under-surface treatment agent, a step of aggregating soil waste, and a step of at least partially classifying the waste by employing real-time scanning technology, the classification being based on a threshold of radioactive contamination, a step of classifying the classified waste based on the classification, and a step of disposing of the waste through at least one of different disposal routes based at least partially on the classification. The method includes reducing radioactive waste from a first contamination threshold to a lower second contamination threshold, resulting in a reduction in the waste class, and the step of disposing of the reduced radioactive waste includes disposing of the waste through a disposal route corresponding to the reduced waste class.

Brief Description of the Drawings

[0006] The various features of the embodiments described herein are particularly set forth in the appended claims. However, these various embodiments can be understood, together with their advantages, in accordance with the following description in conjunction with the accompanying drawings, in terms of both their configuration and method of operation.

[0007]

Figure 1

[0008]

Figure 2

[0009] Corresponding reference numerals indicate corresponding parts throughout several views. The multiple illustrations described herein illustrate various embodiments of the present disclosure in one form, and such multiple illustrations should not be construed as limiting the scope of the present disclosure in any way.

Embodiments for Carrying Out the Invention

[0010] Before describing various aspects of the present disclosure in detail, it should be noted that exemplary embodiments are not limited to the details of the structure and arrangement of the parts illustrated in the accompanying drawings and description in terms of their application or use. Exemplary embodiments may be implemented or incorporated in other aspects, variations, and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the terms and expressions employed herein are selected for the purpose of describing exemplary embodiments for the convenience of the reader and are not intended to be limiting. Also, it is recognized that one or more of the aspects, expressions of aspects, and / or embodiments described below may be combined with any one or more of the other aspects, expressions of other aspects, and / or other embodiments described below.

[0011] In nuclear facilities (e.g., nuclear power plants, research facilities, defense facilities, etc.) where radioactive materials are used and studied, radioactive contaminated waste can be generated. In addition to waste generated during the use and maintenance of the facility, waste can also accumulate during the decommissioning and closure (D&D) of such facilities (e.g., contaminated concrete, contaminated operating systems and components, contaminated soil). As used herein, "D&D" refers to the decommissioning, closure, decontamination, and other processes that are carried out when a nuclear facility ceases operation and enables the reduction or elimination of the site control originally required due to the presence of radioactive materials. The classification of the elements of D&D and the resulting waste is regulated at the national level by, for example, the U.S. Department of Energy and internationally by the International Atomic Energy Agency (IAEA).

[0012] "Radioactively contaminated waste", "waste", "radioactive waste", "D&D-related waste", etc. as described in this specification are used in the same meaning and refer to substances that are at least partially contaminated with radioactivity (e.g., through neutron activation and / or through contact with nuclear fuel or its decay products). In the D&D process, waste can be generated, for example, by the removal of contaminated soil, the treatment and dismantling of contaminated structures, etc. Alternatively or additionally, the waste may be existing and disposed of during the D&D process. This waste can be any material that has undergone at least any one of treatment, classification, and disposal during the D&D process. Also, this waste may be either liquid or solid in nature.

[0013] The waste can be disposed of in a designated method and / or a method regulated by the government in order to reduce or eliminate the risks caused by the radioactive contamination of the waste. The waste can be classified based on at least one of the physical properties of the waste (e.g., solid, liquid), the nature of the contamination (e.g., long-lived or short-lived radioisotopes), and the threshold (e.g., degree) of contamination (e.g., radioactivity per gram of waste).

[0014] Waste classification systems are developed to help determine how a given waste product should be disposed of safely and effectively. For example, the United States Department of Energy has issued regulations at 10 C.F.R. § 61.55 [47 FR 57463, December 27, 1982: Revised 54 FR 22583, May 25, 1989; 66 FR 55792, November 2, 2001], which are incorporated herein by reference. 10 C.F.R. § 61.55 [47 FR 57463, December 27, 1982: Revised 54 FR 22583, May 25, 1989; 66 FR 55792, November 2, 2001] specifies certain thresholds for the presence of radioisotopes in radioactive contaminated waste. The classification of the waste is determined by the combination and amount of isotopes present. The classification of the waste can be, for example, Class C, Class B, Class A in order of decreasing contamination and disposal cost. In some embodiments, Class A waste can be further reduced to exempt this waste.

[0015] As another example, the IAEA issued "Classification of Radioactive Waste, General Safety Guide No. GSG-1" in 2009, which is incorporated herein by reference. This document describes certain criteria for the classification of waste, including, in order of increasing contamination threshold and increasing complexity of required disposal methods, "excluded waste for application", "very low level waste (VLLW)", "low level waste (LLW)", "intermediate level waste", and "high level waste". This document further explains the principles for the classification of waste.

[0016] In various aspects, reducing the class of a given waste (from more contaminated to less contaminated) can enable improved efficiency and / or reduced disposal costs during waste disposal. Further, a process for achieving this reduction has been discovered. This process includes steps that have not been previously carried out in concert, resulting in an effective and efficient reduction of the waste. Accordingly, a method for reducing radioactive waste is disclosed herein. "Reducing radioactive waste", "reducing waste", etc. as described herein means reducing the class of the waste (e.g., by treating the waste, shredding the waste, more specifically classifying the waste, and / or by other methods described herein). For example, an initial portion of waste consisting of Class B waste can be reduced to waste consisting of Class A waste or waste consisting of a mixture of Class B and Class A waste. Similarly, LLW can be reduced at least in part to VLLW and / or excluded waste. Thus, the methods of the present disclosure relate to reducing the class of waste to be disposed of, regardless of the exact classification method used, which may vary by time and location.

[0017] Disposing of radioactive waste, particularly waste that is more highly contaminated and thus classified into a higher class, is expensive, time-consuming, and available only in limited locations. Therefore, reducing radioactive waste is beneficial, for example, during a D&D process. Such waste reduction enables at least a portion of the waste to be disposed of via a less expensive and / or more accessible disposal route.

[0018] Referring to FIG. 1, a method 100 for reducing radioactive contaminated waste can include a step of treating a radioactively contaminated surface 102, a step of treating under the radioactively contaminated surface 104, a step of aggregating soil waste 106, a step of classifying waste by employing real-time scanning technology 108, and a step of disposing of the waste through at least one of different disposal routes based at least in part on the classification 110.

[0019] By implementing the present method 100 and other exemplary methods described herein, radioactive contaminated waste can be consequently reduced. The steps in the methods described herein may be executed in any suitable order and may be designed to improve the waste reduction achieved. Further, the methods described herein enable previously unachievable coordination between various types and steps of waste disposal required, for example, in the D&D process of nuclear facilities. This coordination can further improve waste reduction. For example, the treatment and / or aggregation 102, 104, 106 of the waste described herein may be carried out along with the classification and segregation of the waste provided by the use of real-time scanning technology 108. Thus, for example, the treatment 102, 104 of the waste can achieve a first reduction of the waste (e.g., by removing radioactive contamination), and classifying the waste in real time can achieve a second reduction of the waste by separating treated waste below the contamination threshold from treated waste above the contamination threshold. For example, cementation, pyrolysis, and / or incineration can be optionally used to further improve the reduction of treated Class B, Class C, and / or intermediate-level waste. The technical details and examples of the present method 100 will be discussed below.

[0020] The treatment 102 of the radioactive contaminated surface may include a step of removing radioactive contamination from non-porous and / or metallic surfaces of nuclear facilities (e.g., by dissolving in a treatment liquid). Thereby, reduction of large and heavy waste products can be achieved. By using the treatment 102, any suitable plant system and / or components (e.g., of a nuclear reactor) containing materials chemically affinity with the surface treatment agent can be decontaminated. Nuclear power plants such as PWR, BWR, and CANDU plants all have suitable plant systems and / or components. Exemplary plant systems include reactor recirculation (RRS), reactor water clean-up (RWCU), residual heat removal (RHR), chemical volume control system (CVCS), and primary heat transport system (PHTS). The treatment 102 of the radioactive contaminated surface may include a step of removing radioactive corrosion products from the inner surfaces of tubes, pipes, fluid containers, and other similar equipment using a surface treatment agent.

[0021] The surface treatment agent and its use may comprise a plurality of components and / or processes and may be applied in a single step or multiple steps. Treatment 102 may comprise the step of treating a plant system and / or components in their assembled state and / or in their disassembled state. Examples of surface treatment agents include agents containing oxidizing and reducing chemicals. The first surface treatment 102 may comprise the step of utilizing one or more of the following surface treatment agents and may be performed in any suitable order. For example, reducing chemicals include surface treatment agents such as LOMI and LOMI II (low oxidation state metal ions), CITROX (a surface treatment involving the use of citric and oxalic acids), NITROX-E (a surface treatment involving the use of nitric acid, oxalic acid, and potassium permanganate), CANDEREM (a surface treatment involving the use of EDTA (ethylenediaminetetraacetic acid), citric acid, and ammonium hydroxide), and REMCON (a surface treatment involving the use of ascorbic acid, citric acid, ammonium hydroxide, and a corrosion inhibitor). These surface treatments are directly or indirectly available from the Westinghouse Electric Company, located in Cranberry Township, Butler County, Pennsylvania, USA.

[0022] Oxidizing chemicals that can be used as surface treatment agents include decontamination for decommissioning (DFD) and DFDX (including the use of boric acid fluoride with oxalic acid and potassium permanganate), nitric acid permanganate (NP), alkaline permanganate (AP) (including the use of potassium permanganate with nitric acid or sodium hydroxide), BiOX-2 (including the use of ascorbic acid, citric acid, and ammonium hydroxide with corrosion inhibitors and hydrogen peroxide), and passivation (including the use of a solution of ammonium citrate). These surface treatments are available directly or indirectly from Westinghouse Electric Company, located in Cranberry Township, Butler County, Pennsylvania, USA. Generally, oxidizing chemicals are not used simultaneously and in the same location as reducing chemicals due to incompatibility between the chemicals. Therefore, if it is desirable to use both, these two chemicals can be used sequentially and / or in different locations.

[0023] The surface treatment agent (and process 102) is understood to be capable of removing and / or decontaminating the outer layer of the decontaminated system, component, and / or device. Depending on the type of contamination (e.g., that caused by neutron activation or that beneath the outer layer), it may not be completely removed.

[0024] The apparatus used to perform process 102 may include an apparatus suitable for performing recirculation of the surface treatment chemical components through the contaminated apparatus and / or system. Process 102 may be performed with only a single recirculation apparatus and / or system. Reverse flow of the surface treatment agent through the apparatus and / or system may be employed. The recirculation of the surface treatment agent may be optimized based on the plant system and purification requirements. Apparatus suitable for performing surface treatment 102 may include a pump skid, a chemical mixing tank with an in-line heater, an ion exchange column, and a tank system for material immersion during process 102.

[0025] In addition to the treatment during the assembly of the plant system and / or components in place, treatment 102 using a surface treatment agent for a radioactively contaminated surface may include the disassembly of the plant system and / or components. When disassembly is employed, the contaminated articles may be shredded (e.g., cut into small pieces) and / or treated in a bath. By using any suitable combination of treatment, disassembly, and / or shredding of the plant system and / or components in place, waste reduction can be improved. Treatment in a bath enables, for example, a more targeted treatment for more highly contaminated surfaces and / or treatment for components that are otherwise difficult to access. For example, the surface treatment agent may be able to effectively contact a given surface only when the components are disassembled. Similarly, by shredding the components, the effectiveness of surface treatment 102 can also be improved. Shredding may also make it easier to classify waste based on waste classes. For example, if only a part of a component is contaminated, shredding can prevent the large component from being disposed of as a higher waste class. Thus, by adopting waste shredding prior to treatment 102, the effectiveness of the treatment can be improved, and / or by adopting waste shredding after treating the waste with treatment 102, the classification of waste during the classification 108 process can be improved. As described herein, by combining surface treatment 102 with the disassembly and / or shredding of components, waste reduction can be improved.

[0026] The treatment 104 of a radioactive contaminated surface may include a step of removing radioactive contamination from under the surface, which may include contamination located on or under the surface of the material (e.g., by dissolving in a treatment liquid). Examples of such materials include concrete (e.g., cinder blocks, bricks, and tiles), glass, asphalt, transit (e.g., cement composites), and wood, but may be composed of other materials that require subsurface treatment. The treatment 102 of a radioactive contaminated surface may be performed separately from or simultaneously with the subsurface treatment 104. The treatment 102 of a radioactive contaminated surface and the subsurface treatment 104 of a radioactive contaminated surface may be applied to the same waste (e.g., consecutive treatments 102, 104) or different wastes. Similar to the treatment 102 of a radioactive contaminated surface, the subsurface treatment 104 can also achieve reduction of large and heavy waste products that require more complex and expensive disposal than normal.

[0027] The subsurface treatment 104 may include a step of dissolving and / or removing radioactive contaminants using a surface / subsurface treatment agent. The surface treatment agent and the surface / subsurface treatment agent may include the same type of chemical substance, different types of chemical substances, or a mixture thereof. The surface / subsurface treatment agent may include a plurality of components and / or processes and may be applied together in a single step or multiple steps. It is understood that the surface / subsurface treatment agent (and treatment 104) can dissolve and / or remove radioactive contamination from at least one of the outer surface of the waste and the subsurface location of the waste. Examples of subsurface locations include internal voids in concrete and similar materials.

[0028] Examples of surface / subsurface treatment agents include both liquids and gels that can be applied via spraying or foaming onto contaminated waste. By using Treatment 104, any suitable plant materials and / or components composed of materials that are chemically compatible with the surface treatment agent can be decontaminated. Nuclear facilities containing radioactive contaminated waste may include materials such as walls, ceilings, equipment, structural beams, internal piping, and irregular surfaces, all of which can benefit from Treatment 104 and contribute to waste reduction. Examples of surface / subsurface treatment agents include Rad-Release I and Rad-Release II, which include at least one of organic acids, inorganic acids, salts, surfactants, and chelating agents, and these can act together to facilitate the release and isolation of contamination from porous surfaces and subsurfaces. Another exemplary surface / subsurface treatment agent is EAI SuperGel, which includes nanoparticles and superabsorbent polymer gels. These components react to wetting agents and act to absorb and / or isolate radioactive contamination from contaminated pores in porous surfaces. Rad-Release I and II, and EAI SuperGel are available from Environmental Alternatives, Inc., in Swanzea, New Hampshire, USA. After application, the surface / subsurface treatment agent may be removed by flushing, dewatering, vacuuming, or other means, together with the isolated radioactive contaminants.

[0029] The surface treatment agent and the subsurface treatment agent may be applied via an automated process or a manual process. For example, a portable spray wand or a similar device may be used. Alternatively or additionally, a larger (e.g., remotely operated) spray device including multiple applicators may be used to enable the treatment agent to be applied over a wider area by fewer operators. If a higher level of contamination exists, the treatment steps 102 and 104 may be performed multiple times to improve overall waste reduction.

[0030] Treatment 104 of the porous radioactive contamination material using a surface / subsurface treatment agent may also include the disassembly of the material and / or components. When disassembly is employed, the contaminated material and / or components may be shredded and / or treated in a bath. Similarly, the contaminated material and / or components may be crushed. By using any suitable combination of treatment, disassembly, crushing, and / or shredding of the material and / or components at a given location, waste reduction can be improved. Treatment in a bath enables, for example, more targeted treatment of more highly contaminated material and / or components, and / or treatment of material and / or components that are otherwise difficult to access. For example, the surface treatment agent may be able to effectively contact a given component only when disassembling the component. Similarly, the effect of the surface treatment 104 can be improved by shredding and / or crushing the components. Shredding and / or crushing may also make it easier to classify waste based on waste classes. For example, if only a part of a component is contaminated, shredding and / or crushing can prevent disposing of a large component as a higher waste class. Thus, by employing waste shredding and / or crushing prior to treatment 104, the effectiveness of the treatment can be improved, and / or by employing waste shredding after treating the waste with treatment 104, the classification of the waste during the classification 108 process can be improved. As described herein, combining surface treatment with the disassembly, shredding, and / or crushing of components can improve waste reduction.

[0031] The method 100 may include a step of cementing at least one of liquid waste and solid waste. For example, at least one of Class B, Class C, and intermediate-level waste may be cemented. The liquid waste may include, for example, waste generated by the operation of a nuclear facility or waste generated by D&D processes such as processes 102, 104. Desirably, solid waste (e.g., waste processed during processes 102, 104 or pre-deposited) may also be cemented. The step of cementing the waste may include adding the waste, water, and additives to a metal drum (e.g., 200 liters or 400 liters), surrounding and / or mixing the waste, water, and additives with cement, and curing the mixture to make the waste fixable for subsequent disposal. By dilution, cementing can further reduce the activity of the waste (per volume or mass) before disposal.

[0032] The method 100 may include a step of characterizing the radioactive contamination level of the waste before any of the steps of processes 102, 104, and aggregation 106. The step of characterizing the radioactive contamination level of the waste may include using at least one of a portable ion chamber survey meter, a portable Geiger counter, and a portable scintillation probe. By performing such characterization before the steps of processes 102, 104, and aggregation 106, it becomes possible to focus on the areas that require the most treatment and aggregation in subsequent steps. Conversely, by focusing in this way, the most effective use of resources becomes possible, and the waste can be reduced significantly more than would otherwise be achieved. For example, based on the results of this characterization, certain relatively highly contaminated surfaces or materials may be the subject of multiple rounds of processes 102, 104. In another example, the radioactive contamination of soil waste may be characterized before the step of aggregation 106.

[0033] The method 100 may comprise at least one of a step of pyrolyzing waste and a step of incinerating waste. For example, at least one of Class B, Class C, and intermediate-level waste may be incinerated and / or pyrolyzed. Incineration of waste may comprise a step of burning the waste under oxidizing conditions. A part of the waste may be oxidized and released as non-radioactive combustion gas, while radioactive ash, soot, etc. may be filtered from the gas and / or collected and disposed of by other means. Pyrolysis of waste may comprise a step of heating the waste to induce chemical decomposition in an inert atmosphere. The decomposition products may be separated (e.g., removal of non-radioactive gas and other decomposition products), and radioactive substances may be recovered and disposed of. Thus, pyrolysis and / or incineration of waste can contribute to waste reduction by enabling chemical separation of the non-radioactive portion of the waste from the radioactive portion. The processed 102, 104 waste, and / or the aggregated 106 waste may be pyrolyzed and / or incinerated.

[0034] The method 100 may comprise a step 106 of aggregating soil waste. Soil waste may, for example, be present in nuclear facilities undergoing a D&D process. Soil waste may be generated, for example, by waste that has been stored and / or generated at the facility and has come into contact with soil over time and has been moved. The step 106 of aggregating soil waste may comprise a step of classifying the soil waste based on at least one of the type of radioactive contamination present and the amount of contamination present. Thus, uncontaminated soil and / or soil with minimal contamination (e.g., soil contaminated below a predetermined threshold) may be disposed of at minimal cost or retained on-site, while the remaining portion may be disposed of as reduced radioactive contamination waste.

[0035] In the present method 100, any classification technique suitable for classifying and / or aggregating contaminated soil may be used. For example, the classification technique may include real-time scanning technology. The real-time scanning technology may include a radiation detector configured to measure the radioactivity of waste, and a belt conveyor system configured to separate the waste based on the measured radioactivity. For example, the real-time scanning technology may include a trommel for classifying contaminated soil by size, and a first conveyor belt configured to transport the contaminated soil from the trommel to the radiation detector. The radiation detector may include at least one of a gamma-ray spectrometer, an ion chamber survey meter, a Geiger counter, and any other device suitable for detecting and / or quantifying radiation from waste. When a gamma-ray spectrometer is employed, it may include at least one sodium iodide (NaI) scintillation counter. The radiation detector may be in electrical communication with a computer configured to change the path of the waste on the conveyor belt system based on the amount and / or nature of the radioactivity detected in the waste. For example, waste containing radioactivity exceeding a contamination threshold may exit the conveyor belt system via a first path, and waste containing radioactivity below the contamination threshold may exit the conveyor belt system via a second path, thereby classifying and aggregating the waste. Therefore, only soil waste exceeding the contamination threshold needs to be disposed of, and other waste may be retained at the nuclear facility, thereby further reducing radioactive waste. An example of such real-time scanning technology is the Orion ScanSortSM technology available from John Wood Group plc in Aberdeen, Scotland, UK.

[0036] As described above, real-time scanning technology may be used to aggregate and / or distinguish contaminated soil. Alternatively or additionally, other types of waste, such as materials and components of nuclear facilities processed in steps 102 and 104 of method 100, may be classified, sorted, and / or aggregated using real-time scanning technology. In these examples, the waste may be reduced in size by crushing, shredding, pyrolysis, incineration, or other methods before being sorted and / or aggregated by the real-time scanning technology. Thus, only the waste that exceeds the contamination threshold needs to be disposed of as the corresponding class of controlled radioactive waste, while the other waste may be retained at the nuclear facility or disposed of via alternative, less expensive routes, thereby further reducing radioactive waste.

[0037] When waste is reduced using the methods disclosed herein, the remaining waste can be disposed of via routes that comply with relevant safety guidelines and regulations regarding the disposal and / or retention of radioactive contaminated waste. For the disposal of radioactive contaminated waste, various locations and facilities are provided based on the contamination threshold and type of the waste. Class B and Class C waste (or intermediate-level waste) can be disposed of by the Waste Control Specialists (WCS) in Andrews, TX. Class A waste (or LLW) can be disposed of at the WCS and Energy Solutions (ES) in Clive, Utah. Excluded waste (or VLLW) can be disposed of by the WCS, ES, and US Ecology in Boise, Idaho.

[0038] Thus, the waste may be disposed of via at least one of different disposal routes, at least in part based on the classification of the waste. Since the methods disclosed herein can reduce the amount and / or class of the waste, the waste can be disposed of in part via more expensive and complex routes, while most of the waste can be disposed of via less expensive and simpler routes than would otherwise be achieved.

[0039] All waste reduced by the method 100 need not go through all steps of the method 100. For example, all waste from a contaminated structure need not undergo both the processes of steps 102 and 104. The treatment steps 102 and 104 may be used alone or in combination for the waste, based on chemical compatibility and / or the relative effectiveness of the two treatments 102, 104. Additionally, it is unlikely that the cementation, incineration, pyrolysis, and other options disclosed herein will apply to all waste. FIG. 2 shows a plurality of examples of reducing different types of waste according to different aspects of the method 100. The method 100 can improve the ability to integrally process these various types of waste to efficiently reduce and dispose of the waste.

[0040] Returning to FIGS. 1 and 2, an exemplary reduction of waste from the reactor vessel and / or the reactor interior 220a is shown by path 220. The path 220 may include a step 220b of characterizing the level of radioactive contamination of the waste, as disclosed herein. By performing this characterization prior to at least one of the steps of treatments 102, 104, and aggregation 106, it becomes possible to focus on the areas or subsets of waste that most require treatment and aggregation in subsequent steps. As described above, the characterization 220b of the waste based on the contamination level enables separation 220b of the waste, for example, by cutting, shredding, and / or disassembling, as disclosed herein.

[0041] As disclosed herein, the decontaminated waste of the reactor vessel and / or the reactor interior shown at 220a may be cemented and / or pyrolyzed and packaged for disposal.

[0042] As indicated by the arrows proceeding from path 220, path 220 is expected to generate waste of class B and / or class C, along with waste of class A. Thus, at least a portion of the waste can be reduced from class B and / or class C to class A. The waste may be reduced from class B to class C.

[0043] Exemplary reduction of waste from the reactor system and component 222a is shown by path 222. Path 222 may comprise processes such as process 102 between chemical decontamination 222b of the reactor system and component 222a. Before and after decontamination 222b, shredding 222b of the waste may be employed. By combining decontamination and shredding of 222b, reduction of waste is enabled as disclosed in the present disclosure.

[0044] After step 222b, step 222c may be employed. Step 222c may comprise the use of the real-time scan technology disclosed herein. As disclosed herein, the real-time scan technology may be used for classification, segregation, and / or aggregation of waste such as materials and components of a nuclear facility processed in step 102 of the method 100.

[0045] As indicated by the arrow proceeding from path 222, path 222 is expected to mainly generate Class A waste. Therefore, at least a portion of the waste can be reduced from Class B and / or Class C to Class A. The waste may be reduced to a lower class (e.g., excluded waste) (not shown).

[0046] Exemplary reduction of waste from substances requiring subsurface decontamination (e.g., concrete, other materials disclosed herein) 224a is shown by path 224. Path 224 may comprise process 224b including physical, chemical, and laser decontamination of materials requiring subsurface decontamination 224a. Process 102 and / or 104 of the method 100 may be performed to decontaminate waste 224a during process 224b.

[0047] After step 224b, step 224c may be employed. Step 224c may comprise the use of the real-time scanning techniques disclosed herein. As disclosed herein, the real-time scanning techniques may be used to classify, sort, and / or aggregate waste materials and components of a nuclear facility processed in steps 102, 104 of method 100.

[0048] As indicated by the arrow proceeding from path 224, path 224 is expected to generate a range of classes of waste. Among the materials, there are those with little or no contamination that may be freely released without disposal control. By using real-time scanning techniques during step 224c, it is also possible to separate Class A waste and excluded waste, and further reduce the waste classes.

[0049] An exemplary reduction of soil waste 226a is shown by path 226. Path 226 may comprise step 226b including the remediation and sorting of contaminated soil 226a. For example, this step may include methods for characterizing the level of radioactive contamination of the waste disclosed herein. Additionally, the soil may be manually sorted based on the results of the characterization, followed by an initial collection of the soil for subsequent separation by real-time scanning techniques.

[0050] After step 226b, step 226c may be employed. Step 226c may comprise the use of the real-time scanning techniques disclosed herein. As disclosed herein, the real-time scanning techniques can be used to classify, sort, and / or aggregate soil waste.

[0051] As indicated by the arrow proceeding from path 226, path 226 is expected to generate a range of classes of waste. Using real-time scanning technique 226c as well as manual sorting and purification 226b, it is possible to separate Class A waste, excluded waste, and freely releasable waste.

[0052] Various aspects of the subject matter disclosed in this specification are described in the following examples. (Example 1) A method for reducing radioactive contaminated waste, comprising a step of treating a radioactively contaminated surface, said step of treating the radioactively contaminated surface with a surface treatment agent, a step of treating under the radioactively contaminated surface, said step of treating under the radioactively contaminated surface with a surface / subsurface treatment agent, a step of aggregating soil waste, a step of classifying waste by employing real-time scanning technology, said classification being at least partially based on a threshold of radioactive contamination, and said step of classifying the classified waste based on said classification, a step of disposing of the waste through at least one of different disposal routes, at least partially based on said classification, A method comprising the above. (Example 2) The method according to Example 1, comprising reducing radioactive contaminated waste from a first contamination threshold to a lower second contamination threshold, resulting in a reduction of the waste class. (Example 3) The method according to Example 2, wherein the step of disposing of the reduced radioactive contaminated waste comprises a step of disposing through a disposal route corresponding to the reduced waste class. (Example 4) The method according to any one of Examples 1 to 3, further comprising at least one of a step of pyrolyzing the waste and a step of incinerating the waste. (Example 5) The method according to any one of Examples 1 to 4, further comprising a step of characterizing the radioactive contamination level of the waste before said step of treating and said step of aggregating. (Example 6) The method according to any one of Examples 1 to 5, wherein the real-time scanning technology is employed to aggregate soil waste during said step of aggregating. (Example 7) The real-time scanning technology is A radiation detector configured to measure the radioactivity of waste, A belt conveyor system configured to separate waste based on the measured radioactivity, the method according to Example 6. (Example 8) The method according to Example 7, further comprising performing at least one of classifying and aggregating the processed non-soil waste in at least one of the steps of processing by adopting the real-time scanning technology. (Example 9) The method according to any one of Examples 1 to 8, wherein the step of treating the radioactively contaminated surface comprises a step of disassembling the components and a step of treating the components in a bath. (Example 10) The method according to any one of Examples 1 to 9, further comprising at least one of a step of shredding waste and a step of crushing waste. (Example 11) The method according to any one of Examples 1 to 10, wherein at least one of the surface / subsurface treatment agent and the surface treatment agent is applied via an automatic process. (Example 12) The method according to any one of Examples 1 to 11, wherein at least one of the surface / subsurface treatment agent and the surface treatment agent comprises at least one of salt, surfactant, acid, chelating agent, wetting agent and absorbent gel. (Example 13) The method according to any one of Examples 1 to 12, further comprising a step of solidifying at least one of liquid waste and solid waste. (Example 14) A method for reducing radioactive waste, A step of treating a radioactively contaminated surface, the step of treating the radioactively contaminated surface with a surface treatment agent, A step of treating under the radioactively contaminated surface, the step of treating under the radioactively contaminated surface with a surface / subsurface treatment agent, A step of aggregating soil waste, A process of classifying waste by adopting real-time scanning technology, wherein the classification is at least partially based on a threshold value of radioactive contamination, and the step of classifying the classified waste based on the classification; And a step of disposing of the waste through at least one of different disposal routes at least partially based on the classification. The method includes reducing radioactive contaminated waste from a first contamination threshold value to a lower second contamination threshold value, resulting in a reduction in the waste class. The step of disposing of the reduced radioactive contaminated waste includes the step of disposing through a disposal route corresponding to the reduced waste class. A method. (Example 15) The method according to Example 14, further comprising at least one of a step of pyrolyzing waste and a step of incinerating waste. (Example 16) The method according to Example 14 or 15, further comprising a step of characterizing the radioactive contamination level of the waste before the step of processing and the step of aggregating. (Example 17) The real-time scanning technology is A radiation detector configured to measure the radioactivity of waste, And a belt conveyor system configured to separate waste based on the measured radioactivity. The method according to any one of Examples 14 to 16. (Example 18) The step of treating the radioactively contaminated surface includes a step of disassembling components and a step of treating the components in a bath. The method according to any one of Examples 14 to 17. (Example 19) The method according to any one of Examples 14 to 18, further comprising at least one of a step of shredding waste and a step of crushing waste. (Example 20) The method according to any one of Examples 14 to 19, further comprising a step of solidifying at least one of liquid waste and solid waste.

[0053] As is apparent from the above disclosure, unless otherwise specified, throughout the above disclosure, in discussions using terms such as "processing", "calculating", "computing", "determining", "displaying", etc., data represented as physical (electronic) quantities in the registers and memories of a computer system is recognized as referring to the operations and processes of a computer system or a similar electronic computing device that manipulates and transforms the data into other data similarly represented as physical quantities in the memory or registers of the computer system, or in other such information storage devices, transmission devices, or display devices.

[0054] In this specification, reference may be made to one or more components as being "configured to", "configurable to", "operable / operating to", "adapted / adaptable to", "capable of", "adaptable / adapted to", etc. Those skilled in the art will recognize that, unless the context requires a different meaning, "configured to" generally may include components in an active state and / or components in a non-active state and / or components in a standby state.

[0055] Those skilled in the art will generally recognize that the terms used herein, particularly in the appended claims (e.g., the body of the appended claims), are generally intended to be “open” terms (e.g., the term “comprising” should be interpreted as “comprising but not limited to,” “having” should be interpreted as “having at least,” “including” should be interpreted as “including but not limited to,” etc.). If a specific number in the description of an introduced claim is intended, such intent will be explicitly stated in the claim, and it will be further understood by those skilled in the art that such intent does not exist if there is no such recitation. For example, for the sake of understanding, the appended claims below may include the use of introductory phrases “at least one” and “one or more” to introduce the claim description. However, the use of such phrases should not be construed as implying that the introduction of a claim description by the indefinite article “a” or “an” limits any particular claim including such introduced claim description to a claim including only one such recitation, even if the introduced claim description includes “one or more” or “at least one” as an introductory phrase and the indefinite article “a” or “an” (e.g., “a” and / or “an” should generally be interpreted as meaning “at least one” or “one or more”). The same applies to the use of the definite article used to introduce the claim description.

[0056] In addition, even if a specific number in the description of the introduced claim is explicitly recited, one of ordinary skill in the art will recognize that such a recitation should generally be construed as meaning at least the recited number (e.g., a mere recitation of "two recitations" without other modifiers will generally be construed as meaning at least two recitations, or two or more recitations). Further, in examples where a convention similar to "at least one of A, B, and C, etc." is used, generally such a construction is intended in the sense that one of ordinary skill in the art will understand the convention (e.g., a "system having at least one of A, B, and C" includes, but is not limited to, a system having only A, only B, only C, only A and B, only A and C, only B and C, and / or a combination of A, B, and C). Further, in examples where a convention similar to "at least one of A, B, or C, etc." is used, generally such a construction is intended in the sense that one of ordinary skill in the art will understand the convention (e.g., a "system having at least one of A, B, or C" includes, but is not limited to, a system having only A, only B, only C, only A and B, only A and C, only B and C, and / or a combination of A, B, and C). One of ordinary skill in the art will further understand that disjunctive words and / or terms presenting two or more alternative terms, regardless of whether in the description, claim, or drawing, should generally be understood to contemplate the possibility of including one of the terms, any of the terms, or both terms, unless the context indicates otherwise. For example, the term "A or B" will generally be understood to include the possibilities of "A" or "B", or "A and B".

[0057] Regarding the appended claims, one of ordinary skill in the art will recognize that the operations described herein may generally be performed in any order. Also, while various operation flowcharts are presented sequentially, it should be understood that these various operations may be performed in an order different from the order shown, or may be performed simultaneously. Examples of such alternative orderings may include, unless the context dictates otherwise, repetition, interleaving, interruption, reordering, incremental, preparatory, supplementary, simultaneous, reverse, or other variations of ordering. Further, terms such as "corresponding to", "related to", or other past tense adjectives are not intended to exclude such variations unless the context dictates otherwise.

[0058] It should be noted that any reference to "one aspect", "an aspect", "an illustration", "one illustration", etc. means that the specific features, structures, or characteristics described in relation to that aspect are included in at least one aspect. For this reason, the appearance of the phrases "in one aspect", "in an aspect", "in an illustration", "in one illustration" at various places throughout this specification does not necessarily refer to the same aspect. Further, the specific features, structures, or characteristics may be combined in any suitable manner in one or more aspects.

[0059] Any patent application, patent, non-patent literature, or other disclosure material mentioned in this specification and / or listed in any application data sheet is incorporated herein by reference to the extent that the incorporated material does not conflict with this specification. Thus, to the extent necessary, the disclosure explicitly set forth in this specification supersedes the conflicting material incorporated herein by reference. Any material or portion thereof that is purported to be incorporated herein by reference but conflicts with an existing definition, statement, or other disclosure material set forth in this specification is incorporated only to the extent that no conflict arises between the incorporated material and the existing disclosure material.

[0060] The terms "comprise" (and any form of "comprise" such as "comprises" or "comprising"), "have" (and any form of "have" such as "has" or "having"), "include" (and any form of "include" such as "includes" or "including"), and "contain" (and any form of "contain" such as "contains" or "containing") are open-ended linking verbs. As a result, a system that "comprises", "has", "includes", or "contains" one or more elements has those one or more elements but is not limited to having only those one or more elements. Similarly, an element of a system, device, or apparatus that "comprises", "has", "includes", or "contains" one or more features has those one or more features but is not limited to having only those one or more features.

[0061] In summary, many of the advantages resulting from adopting the concepts described herein have been described. The description of one or more of the above forms is presented for purposes of illustration and explanation. It is not intended to cover or limit the exact forms disclosed. Modifications and variations are possible in light of the above teachings. The one or more of the above forms have been selected and described to illustrate the principles and practical applications, and thereby enable one of ordinary skill in the art to utilize them with various forms and various modifications suitable for a particular intended use. The claims presented herein are intended to define the overall scope.

Claims

1. A method for reducing radioactive contaminated waste, comprising: A step of treating a radioactively contaminated surface, the step of treating the radioactively contaminated surface with a surface treatment agent; A step of treating the area beneath the radioactively contaminated surface, the step of treating the area beneath the radioactively contaminated surface with a surface / subsurface treatment agent; A step of aggregating soil waste; After the step of treating the radioactively contaminated surface, the step of treating the area beneath the radioactively contaminated surface, and the step of aggregating the soil waste, a step of classifying the waste by adopting real-time scanning technology at least partially based on a radioactive contamination threshold; A step of classifying the waste based on the classification generated from the step of classifying the waste by adopting real-time scanning technology; A step of disposing of the waste through at least one of different disposal routes, each of the disposal routes being selected at least partially based on the step of classifying; At least one of a step of pyrolyzing at least a part of the waste and a step of incinerating the waste; A method comprising the above steps.

2. The method according to claim 1, further comprising a step of reducing radioactive contaminated waste from a first contamination threshold to a lower second contamination threshold.

3. The method according to claim 2, wherein the step of disposing of the waste comprises a step of disposing of the waste through a disposal route corresponding to the lower second contamination threshold.

4. The method according to any one of claims 1 to 3, further comprising a step of characterizing the radioactive contamination level of the waste before the step of treating and the step of aggregating.

5. The method according to any one of claims 1 to 4, wherein the real-time scanning technology is adopted to aggregate the soil waste during the step of aggregating the soil waste.

6. The real-time scanning technology comprises: A radiation detector configured to measure the radioactivity of the waste; A belt conveyor system configured to separate the waste based on the measured radioactivity, the belt conveyor system comprising different paths corresponding to the different disposal routes. The method according to any one of claims 1 to 5.

7. A method according to claim 6, further comprising performing at least one of classifying and aggregating non-soil waste treated in at least one of the step of treating the radioactive contaminated surface and the step of treating under the radioactive contaminated surface, using the real-time scanning technique.

8. The method according to any one of claims 1 to 7, wherein the step of treating the radioactive contaminated surface includes a step of disassembling a component and a step of treating the component in a bath.

9. The method according to any one of claims 1 to 8, further comprising at least one of a step of shredding waste and a step of crushing waste.

10. The method according to any one of claims 1 to 9, wherein at least one of the surface / subsurface treatment agent and the surface treatment agent is applied via an automated process.

11. The method according to any one of claims 1 to 10, wherein at least one of the surface / subsurface treatment agent and the surface treatment agent contains at least one of salt, surfactant, acid, chelating agent, wetting agent and absorbent gel.

12. The method according to any one of claims 1 to 11, further comprising a step of solidifying at least one of liquid waste and solid waste.

13. The method according to claim 1, wherein the surface treatment agent contains an oxidizing chemical substance or a reducing chemical substance.

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