Method and system for flushing radionuclides from resin-packed columns

Abstract

A method for radionuclide waste extraction includes directing a waste stream from an upstream segment of a main waste pathway into a waste stream input of an anion exchange column, the waste stream including uranium and a target radionuclide, the anion exchange column containing an anion exchange resin, a cation exchange column containing a cation exchange resin fluidly coupled to the anion exchange column downstream of the anion exchange column, and a flushing and preparation tank fluidly coupled to the anion exchange column. The method further includes adsorbing uranium from the waste stream onto the anion exchange resin, directing the waste stream from the anion exchange column into the cation exchange column, adsorbing the radionuclides onto the cation exchange resin, removing used anion exchange resin from the anion exchange column, and directing new anion exchange resin from the flushing and preparation tank into the anion exchange column.

Description

[Technical Field]

[0001] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This disclosure was developed with government support under Contract No. DE-NA0004010 awarded by the U.S. Department of Energy. The government has certain rights in this disclosure.

[0002] FIELD OF THE DISCLOSURE The present disclosure generally relates to systems and methods for extracting waste radionuclides, such as those produced in medical isotope production processes. [Background technology]

[0003] Current technologies for nuclear waste separation include solvent-based extraction, also known as solvent extraction or liquid-liquid extraction. Solvent extraction is a separation technique in which an extractant-containing organic phase is contacted with a metal ion-containing aqueous phase. Upon mixing, the metal ions migrate from the aqueous phase to the organic phase. Despite industrial reliance, solvent extraction has many drawbacks, including challenges associated with phase separation, the formation of heavy or "third" phases, and the generation of large amounts of hazardous organic waste. The process's reliance on hazardous aromatic organic solvents presents particular challenges from an environmental management perspective. Many commercial waste haulers have low tolerance for the presence of benzene or other aromatic hydrocarbons in solidified waste.

[0004] Thus, there is a need for improved methods and systems for nuclear waste separation, for example, in medical isotope production processes. Summary of the Invention

[0005] According to a first aspect of the present disclosure, a method for radionuclide waste extraction includes directing a waste stream from an upstream segment of a main waste pathway into a waste stream input of an anion exchange column, the waste stream including uranium and one or more target radionuclides, the anion exchange column containing an anion exchange resin, a cation exchange column containing a cation exchange resin fluidly coupled to the anion exchange column along the main waste pathway and positioned downstream of the anion exchange column, and a sluicing preparation tank fluidly coupled to the anion exchange column. The method further includes adsorbing uranium from the waste stream onto the anion exchange resin contained in the anion exchange column, directing the waste stream from the anion exchange column into the cation exchange column, adsorbing one or more target radionuclides onto the cation exchange resin contained in the cation exchange column, removing used anion exchange resin from the anion exchange column, and directing new anion exchange resin from the sluicing preparation tank into the anion exchange column.

[0006] A second embodiment includes the method of the first embodiment, wherein the one or more radionuclides of interest include strontium-90 and cesium-137.

[0007] A third embodiment includes the method of the first embodiment or the second embodiment, wherein the anion exchange resin has an initial adsorption capacity and the used anion exchange resin has an adsorption capacity of 85% or less of the initial adsorption capacity.

[0008] A fourth aspect includes the method of any of the preceding aspects, further comprising directing a waste stream from the cation exchange column to a column effluent tank, wherein the waste stream entering the column effluent tank comprises less than 0.04 curies per cubic meter of strontium-90 and less than 1 curie per cubic meter of cesium-137.

[0009] A fifth aspect includes the method of any of the preceding aspects, further comprising, before removing the spent anion exchange resin, directing the elution acid into an anion exchange column to desorb the uranium from the anion exchange resin in a first elution acid wash to form a uranium waste stream; and after the first elution acid wash, directing the waste stream from the upstream segment of the main waste pathway into an anion exchange column to adsorb the uranium onto the anion exchange resin.

[0010] A sixth aspect includes the method of the fifth aspect, further comprising directing the uranium waste stream from the anion exchange column along a strip waste path to a column waste tank, the strip waste path extending from the anion exchange column to the column waste tank bypassing the cation exchange column.

[0011] A seventh aspect includes the method of the fifth aspect, further comprising directing the uranium waste stream from the anion exchange column along a strip path to a secondary recovery tank and directing the waste stream from the cation exchange column to a column waste tank.

[0012] An eighth aspect includes the method of any of the fifth to seventh aspects, further comprising: after the first elution acid wash and before removing the spent anion exchange resin, directing the elution acid to an anion exchange column to desorb the uranium from the anion exchange resin in a second elution acid wash; and after the second elution acid wash, directing a waste stream from an upstream segment of the main waste pathway into an anion exchange column to adsorb the uranium onto the anion exchange resin.

[0013] A ninth aspect includes the method of any of the fifth to eighth aspects, further comprising performing at least three elution acid washes before removing the spent anion exchange resin and directing fresh anion exchange resin from the flushing wash preparation tank into the anion exchange column.

[0014] A tenth aspect includes the method of any of the preceding aspects, wherein removing the spent anion exchange resin from the anion exchange column comprises stopping the flow of the waste stream from the upstream segment of the main waste pathway into the waste stream input of the anion exchange column and directing the spent anion exchange resin from the anion exchange column into the spent resin tank; and wherein directing fresh anion exchange resin from the flushing and preparation tank into the anion exchange column occurs while the flow of the waste stream from the upstream segment of the main waste pathway is stopped, and the method further comprises resuming the flow of the waste stream from the upstream segment of the main waste pathway into the waste stream input of the anion exchange column after directing the fresh anion exchange resin from the flushing and preparation tank into the anion exchange column.

[0015] An eleventh aspect includes the method of any of the preceding aspects, wherein the flushing preparation tank is fluidly coupled to the cation exchange column, and the method further comprises removing spent cation exchange resin from the cation exchange column and directing fresh cation exchange resin from the flushing preparation tank to the anion exchange column.

[0016] A twelfth aspect includes the method of any of the first to tenth aspects, wherein the flushing preparation tank is a first flushing preparation tank, and the method further comprises removing spent cation exchange resin from the cation exchange column and directing fresh cation exchange resin from the second flushing preparation tank into the cation exchange column.

[0017] A thirteenth aspect includes the method of any of the preceding aspects, wherein the waste stream in the upstream segment of the primary waste pathway contains uranium at least 1 gram / liter, and the waste stream in the upstream segment of the primary waste pathway contains uranium at a gram / liter level that is at least 500 times higher than the gram / liter levels of both strontium-90 and cesium-137.

[0018] According to a fourteenth aspect of the present disclosure, a waste extraction system includes an anion exchange column containing an anion exchange resin and fluidly coupled to an upstream segment of a main waste pathway; a cation exchange column containing a cation exchange resin and fluidly coupled to the anion exchange column along the main waste pathway, the anion exchange column being upstream of the cation exchange column; a column waste tank positioned downstream of the anion exchange column and the cation exchange column; a flushing wash preparation tank fluidly coupled to the anion exchange column; and a radiation shielding system positioned between the flushing wash preparation tank and both the anion exchange column and the cation exchange column, the radiation shielding system forming a radiation barrier between the flushing wash preparation tank and both the anion exchange column and the cation exchange column.

[0019] A fifteenth aspect includes the waste extraction system of the fourteenth aspect, wherein the flushing preparation tank is fluidly connected to the anion exchange column by an anion exchange resin input line, and the flushing preparation tank is fluidly connected to the cation exchange column by a cation exchange resin input line.

[0020] A sixteenth aspect includes the waste extraction system of the fourteenth aspect, wherein the flushing preparation tank is a first flushing preparation tank, and the waste extraction system comprises a second flushing preparation tank fluidly coupled to the cation exchange column, the first flushing preparation tank containing fresh anion exchange resin, and the second flushing preparation tank containing fresh cation exchange resin.

[0021] A seventeenth aspect includes the waste extraction system of any of the fourteenth through sixteenth aspects, further comprising an elution acid source fluidly coupled to the anion exchange column.

[0022] An eighteenth embodiment includes the waste extraction system of the seventeenth embodiment, wherein the anion exchange column comprises a waste stream input and an eluate input, each located at a first end of the anion exchange column, the waste stream input fluidly coupled to an upstream segment of the main waste pathway and the eluate input fluidly coupled to a source of elution acid, and a waste stream outlet and an eluate outlet, each located at a second end of the anion exchange column, the eluate outlet fluidly coupled to the strip waste pathway and the waste stream outlet fluidly coupled to the cation exchange column.

[0023] A nineteenth embodiment includes the waste extraction system of the eighteenth embodiment, wherein the strip waste path extends from the anion exchange column to the column waste tank, bypassing the cation exchange column.

[0024] A twentieth embodiment includes the waste extraction system of the eighteenth embodiment, wherein the strip waste path extends from the anion exchange column to a secondary collection tank.

[0025] These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description taken in conjunction with the drawings.

[0026] The embodiments set forth in the drawings are illustrative and exemplary in nature and are not intended to limit the subject matter defined by the claims. The following detailed description of illustrative embodiments can be understood when read in conjunction with the following drawings, in which like structure is indicated with like numerals and in which: [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic diagram of a waste extraction system including a flushing preparation tank according to one or more embodiments shown and described herein; FIG. [Figure 2]FIG. 1 is a schematic diagram of a waste extraction system including a flushing preparation tank and a secondary collection tank according to one or more embodiments shown and described herein. [Figure 3] FIG. 1 is a schematic diagram of a waste extraction system with two flushing preparation tanks according to one or more embodiments shown and described herein. [Figure 4] FIG. 1 is a schematic diagram of a waste extraction system including two flushing preparation tanks and a secondary collection tank according to one or more embodiments shown and described herein. [Figure 5] FIG. 5 is a schematic diagram illustrating ion exchange resins contained in the anion and cation exchange columns of any of the waste extraction systems of FIGS. 1-4, according to one or more embodiments shown and described herein. DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring generally to the drawings, embodiments of the present disclosure are directed to a waste extraction system and method for the removal of target waste radionuclides from a waste stream, for example, a waste stream formed during a medical isotope production process, such as a molybdenum-99 (Mo-99) production process. The waste stream contains multiple radionuclides, such as uranium-235 (U-235), cesium-137 (Cs-137), and strontium-90 (Sr-90). The waste extraction system includes an anion exchange column containing an anion exchange resin and a cation exchange column containing a cation exchange resin. The anion and cation exchange columns are fluidly coupled to a main waste pathway such that the waste stream passes through the anion and cation exchange columns to reach a column waste tank for final treatment.

[0029] The anion exchange column is positioned upstream of the cation exchange column along the primary waste path such that the waste stream passes through the anion exchange column before passing through the cation exchange column. The anion exchange resin contained in the anion exchange column is configured to selectively adsorb a primary radionuclide, such as uranium, and the cation exchange resin contained in the cation exchange column is configured to selectively adsorb one or more target radionuclides, such as Cs-137 and Sr-90. The anion exchange column provides a manner for removing primary radionuclides from the waste stream such that the waste stream passing through the cation exchange column contains minimal primary radionuclides. This allows the one or more auxiliary adsorption columns to remove other target radionuclides, such as Cs-137 and Sr-90, from the waste stream that may be present in smaller amounts than the primary radionuclides in the initial waste stream.

[0030] During operation, the primary radionuclides are present in greater amounts in the initial waste stream than the other radionuclides of interest. Therefore, the anion exchange resin reaches its maximum adsorption capacity more quickly than the cation exchange resin. In this regard, the waste extraction system further includes a flushing preparation tank fluidly coupled to the anion exchange column, facilitating efficient exchange of fresh anion exchange resin onto the anion exchange column by flushing. The waste extraction system also includes a radiation shielding system disposed between the flushing preparation tank and both the anion exchange column and the cation exchange column, minimizing radiation exposure at the flushing preparation tank while allowing the flushing preparation tank to be reloaded during operation of the waste extraction system. Embodiments of a waste extraction system and a method of radionuclide waste extraction using the waste extraction system are described herein. Where possible, the same reference numerals are used throughout the drawings to refer to the same or similar parts.

[0031] 1-4, several illustrative embodiments of a waste extraction system 100 are shown. The waste extraction system 100 includes an anion exchange column 120 (FIG. 5) containing an anion exchange resin 112 and a cation exchange column 130 (FIG. 5) containing a cation exchange resin 116. The anion exchange column 120 and the cation exchange column 130 are fluidly coupled to a main waste pathway 160, which includes one or more pipes, tubes, or other fluid transport mechanisms for facilitating the flow of waste streams from a production facility through the anion exchange column 120 and the cation exchange column 130 to a column waste tank 150 and ultimately to a waste tank 152. One or more pumps 180 are coupled to the main waste pathway 160 to assist in generating fluid flow within the main waste pathway 160. In one example operation, the upstream segment 162 of the main waste pathway 160 fluidly connects the waste extraction system 100 to a production area of ​​a medical isotope production facility, and the waste stream includes radionuclide waste produced by the medical isotope production process.

[0032] The anion exchange column 120 and the cation exchange column 130 are positioned between and fluidly coupled to an upstream segment 162 of the main waste pathway 160 and the column effluent tank 150. During operation, a waste stream containing radionuclide waste enters the waste extraction system 100 along the upstream segment 162 of the main waste pathway 160 (e.g., the initial waste stream). The anion exchange column 120 is fluidly coupled to the upstream segment 162 of the main waste pathway 160 and is positioned upstream of the cation exchange column 130 along the main waste pathway 160. During operation, the waste stream passes through the anion exchange column 120 and then through the cation exchange column 130 along the main waste pathway 160. During operation, the anion exchange resin 112 contained in the anion exchange column 120 adsorbs primary radionuclides, such as uranium (e.g., U-235), from the waste stream to reduce the amount of primary radionuclides in the waste stream entering the cation exchange column 130. The cation exchange resin 116 contained in the cation exchange column 130 then adsorbs one or more target radionuclides, such as Cs-137 and Sr-90, from the waste stream.

[0033] Column waste tank 150 is fluidly coupled to main waste pathway 160 and receives the modified waste stream (e.g., a waste stream with reduced amounts of Cs-137 and Sr-90) from cation exchange column 130. In some embodiments, as shown in Figures 1 and 3, column waste tank 150 is also coupled to strip waste pathway 170 that extends from anion exchange column 120 to column waste tank 150 such that the modified waste stream from cation exchange column 130 mixes with the primary radionuclide waste stream from anion exchange column 120 in column waste tank 150, as described in more detail below. In another embodiment, as shown in Figures 2 and 4, the column waste tank 150 is fluidly coupled to the primary waste pathway 160, and the secondary recovery tank 154 is fluidly coupled to the strip waste pathway 170, such that the modified waste stream from the cation exchange column 130 reaches the column waste tank 150 and the primary radionuclide waste stream from the anion exchange column 120 reaches the secondary recovery tank 154.

[0034] The waste tank 152 is fluidly coupled to the column effluent tank 150 by a waste tank segment 166 of the main waste pathway 160. The waste in the column effluent tank 150 may be directed along the waste tank segment 166 into the waste tank 152 for final off-site treatment and removal. This final treatment may include solidifying the resulting waste with concrete to form a solid final waste, which may occur in the waste tank 152. In some embodiments, the column effluent tank 150 and the waste tank 152 are of the same volume, e.g., 50 gallons, in the range of 25 gallons to 75 gallons. In other embodiments, the column effluent tank 150 and the waste tank 152 are of different volumes, which may range from 25 gallons to 75 gallons. By using the waste extraction system 100 to remove the radionuclides of interest, the waste received by the column effluent tank 150 and the waste tank 152 contains lower levels of radioactivity than the initial waste stream. In fact, radionuclides of interest contribute a disproportionate amount to the total radioactivity in the initial waste stream. For example, because Cs-137 is a gamma-emitting nuclide, it is desirable to minimize the amount of Cs-137 in the resulting waste. By adsorbing radionuclides of interest, such as Cs-137 and Sr-90, these radionuclides can be disposed of separately from the rest of the waste, for example, in a minimal volume sealed in concrete.

[0035] By removing the primary radionuclides from the waste stream in the anion exchange column 120, the cation exchange column 130 may more efficiently and effectively adsorb other radionuclides of interest. Without being limited by theory, the primary radionuclide present in the initial waste stream (e.g., uranium) is adsorbed to the cation exchange resin 116 (along with one or more radionuclides of interest) in the cation exchange column, and the relatively large amount of the target radionuclides causes the cation exchange resin 116 to reach its adsorption limit before removing the desired amount of the target radionuclides. For example, the initial waste stream may contain uranium at a gram / liter level at least 500 times higher than the gram / liter levels of both strontium-90 and cesium-137, e.g., at least 750 times higher, at least 1000 times higher, at least 1250 times higher, at least 1500 times higher, at least 2000 times higher, or a multiplier of a range having any two of these values ​​as endpoints. In some embodiments, the initial waste stream may contain uranium at a gram / liter level at least 500 times higher than the gram / liter level of any of the following radionuclides individually: barium, cerium, lanthanum, molybdenum, neodymium, palladium, praseodymium, rubidium, rhodium, ruthenium, samarium, yttrium, and zirconium, e.g., at least 750 times higher, at least 1000 times higher, at least 1250 times higher, at least 1500 times higher, at least 2000 times higher, or a range containing any two of these values ​​as endpoints. Additionally, uranium may comprise 40% to 60% by weight of the total radionuclides in the initial waste stream.

[0036] In some embodiments, the initial waste stream contains 1 gram / liter or more of uranium, such as 1.5 grams / liter, 2 grams / liter or more, 2.5 grams / liter or more, 3 grams / liter or more, and ranges having any two of these values ​​as endpoints. While Cs-137 and Sr-90 are referred to as the target radionuclides in the embodiments described herein, other target radionuclides may be present in the waste stream and adsorbed to the cation exchange resin 116. For example, other target radionuclides present in the waste stream and adsorbed to the cation exchange resin 116 include barium, cerium, cesium, lanthanum, molybdenum, sodium, neodymium, palladium, plutonium, praseodymium, rubidium, rhodium, ruthenium, samarium, strontium, yttrium, zirconium, protactinium, or combinations thereof. Furthermore, it should be understood that embodiments are contemplated in which other radionuclides in addition to uranium are the primary radionuclides.

[0037] 1-4 , anion exchange column 120 comprises a waste stream input 123 and an eluate input 124, each located at a first end 121 of anion exchange column 120, and a waste stream output 125 and an eluate output 126, each located at a second end 122 of anion exchange column 120. Waste stream input 123 is fluidly coupled to an upstream segment 162 of main waste pathway 160, and waste stream output 125 is fluidly coupled to an inter-column segment 165 of main waste pathway 160. In some embodiments, first end 121 of anion exchange column 120 is opposite second end 122 of anion exchange column 120, and first end 121 of anion exchange column 120 is above second end 122 of anion exchange column 120. This orientation facilitates gravity-assisted flow of the waste stream through anion exchange column 120. Gravity-assisted flow may reduce the pump pressure and pump power required to drive the waste stream through the anion exchange column 120. Gravity-assisted flow may also maximize contact between the anion exchange resin 112 and the waste stream, maximizing adsorption of primary radionuclides. The anion exchange column 120 further comprises a resin input 127 and a resin outlet 128. The resin input 127 is fluidly coupled to a flushing preparation tank 140 (e.g., the flushing preparation tank 140 in FIGS. 1 and 2 or the first flushing preparation tank 140a in FIGS. 3 and 4) by an anion exchange resin input line 142. The resin outlet 128 is fluidly coupled to a used resin tank 156 by an anion exchange resin outlet line 157.

[0038] The cation exchange column 130 includes a waste stream input 134 and a waste stream output 135. The waste stream input 134 is located at a first end 131 of the cation exchange column 130, and the waste stream output 135 is located at a second end 132 of the cation exchange column 130. Furthermore, in some embodiments, the first end 131 of the cation exchange column 130 is opposite the second end 132, and the first end 131 of the cation exchange column 130 is above the second end 132. This orientation promotes gravity-assisted flow of the waste stream through the cation exchange column 130. Gravity-assisted flow may reduce the pump pressure and pump power required to drive the waste stream through the cation exchange column 130. Gravity-assisted flow may also maximize contact between the cation exchange resin 116 and the waste stream, maximizing adsorption of the target radionuclides. Although a single cation exchange column 130 is shown, it should be understood that additional cation exchange columns may be included to adsorb additional amounts of the radionuclides of interest. For example, although not shown, a second cation exchange column is contemplated, positioned along the main waste path 160 between the cation exchange column 130 and the column waste tank 150, and fluidly coupled to the cation exchange column 130 and the column waste tank 150 by an additional inter-column segment 165 and pump 180.

[0039] In some embodiments, the cation exchange column 130 further comprises a resin input 137 and a resin discharge 138. The resin input 137 is fluidly coupled to a flushing preparation tank (e.g., the flushing preparation tank 140 in FIGS. 1 and 2 or the second flushing preparation tank 140b in FIGS. 3 and 4) by a cation exchange resin input line 144. The resin discharge 138 is fluidly coupled to a spent resin tank 156 by a cation exchange resin discharge line 159. While the cation exchange column 130 is coupled to the flushing preparation tank 140 in the embodiment shown in FIGS. 1-4, embodiments are contemplated in which only the anion exchange column 120 is coupled to the flushing preparation tank 140. In practice, during operation, the anion exchange resin 112 needs to be replaced more frequently than the cation exchange resin 116. The cation exchange column 130 may be operable for a sufficient period of time without the use of the flushing preparation tank 140.

[0040] The spent resin tank 156 may also be fluidly coupled to the waste tank 152 by a resin waste pathway 190 so that spent resin removed from the anion exchange column 120 and the cation exchange column 130 may be directed into the waste tank 152 using, for example, the flush pump 182. The spent resin may be directed along the resin waste pathway 190 into the waste tank 152 for final processing and removal off-site. This final processing may include concrete solidification of the spent resin to form a solid final waste, which may occur in the waste tank 152, either independently of or in conjunction with the resulting waste.

[0041] 1-4, the eluate input 124 of the anion exchange column 120 is fluidly coupled to an eluate pathway 172 that extends from an elution acid source 175 to the eluate input 124. The eluate outlet 126 is fluidly coupled to a strip waste pathway 170. One or more of the pumps 180 may be fluidly coupled to the strip waste pathway 170 to help facilitate fluid flow within the strip waste pathway 170. During operation, elution acid may be directed into the anion exchange column 120 through the elution acid input 124. The elution acid flows through the anion exchange column 120, performing an elution acid wash to desorb primary radionuclides (e.g., uranium) from the anion exchange resin 112 (FIG. 5) and form a primary radionuclide waste stream (e.g., uranium waste stream). The primary radionuclide waste stream may be directed from the anion exchange column 120 through the eluate outlet 126 into a strip waste path 170, where the uranium waste stream is directed to the column waste tank 150 (FIGS. 1 and 3) or the secondary recovery tank 154 (FIGS. 2 and 4).

[0042] 1 and 3, strip waste path 170 extends from anion exchange column 120 to column waste tank 150, bypassing cation exchange column 130 while providing a flow path from anion exchange column 120 to column waste tank 150. In other embodiments, as shown in FIGS. 2 and 4, strip waste path 170 extends from anion exchange column 120 to secondary collection tank 154, providing a flow path for removed primary radionuclides to flow to secondary collection tank 154 for recovery and possible reuse. In embodiments in which waste extraction system 100 is part of a medical isotope production facility, the recovered primary radionuclides, such as uranium, may be used to produce additional medical isotopes, which may then be processed by waste extraction system 100 as part of the waste stream. 1-4, the primary radionuclide waste stream bypasses cation exchange column 130 by flowing through strip waste path 170, allowing cation exchange column 130 to adsorb other target radionuclides present in the initial waste stream at lower levels than the primary radionuclides, such as Cs-137 and Sr-90. In other words, strip waste path 170 provides a pathway for primary radionuclides removed from the initial waste stream by anion exchange column 120 to reach a storage location without passing through cation exchange column 130.

[0043] 1-4 , one or more flushing pumps 182 are fluidly coupled to the anion exchange resin input line 142, the cation exchange resin input line 144, the anion exchange resin output line 157, and the cation exchange resin output line 159 to facilitate the movement of fresh resin into the anion exchange column 120 and / or the cation exchange column 130 and the removal of used resin from the anion exchange column 120 and / or the cation exchange column 130. The flushing pumps 182 may comprise any pump configured to pump a combination of solids and liquids, such as a slurry pump. Before the waste stream is directed into the anion exchange column 120, the anion exchange resin 112 comprises fresh resin. As used herein, “fresh resin” refers to an ion exchange resin (e.g., an anion exchange resin or a cation exchange resin) that comprises at least 95% of its initial adsorption capacity. In fact, in some embodiments, a "fresh resin" comprises at least 99% of its initial adsorption capacity, and in some embodiments, may comprise 100% of its initial adsorption capacity. After the anion exchange resin 112 adsorbs the primary radionuclides and an elution acid wash is performed, the anion exchange resin 112 does not return to its initial adsorption capacity. After each subsequent elution acid wash, the anion exchange resin 112 will have a smaller percentage of its initial adsorption capacity than after the immediately preceding elution acid wash. After multiple elution acid washes, the adsorption capacity will no longer be sufficiently effective at adsorbing primary radionuclides from the waste stream.

[0044] 1 and 2, the flushing preparation tank 140 is fluidly coupled to both the anion exchange column 120 and the cation exchange column 130. For example, the flushing preparation tank 140 is fluidly coupled to the anion exchange column 120 by an anion exchange resin input pathway 142 and to the cation exchange column 130 by a cation exchange resin input pathway 144. As shown, in some embodiments, the anion exchange resin input pathway 142 and the cation exchange resin input pathway 144 are each coupled to the flushing preparation tank 140 by a shared pathway segment 143. The shared pathway segment 143 is connected to the anion exchange resin input pathway 142 and the cation exchange resin input pathway 144 by a directional valve 145 that selectively directs fresh resin toward either the anion exchange column 120 or the cation exchange column 130. In other embodiments, the anion exchange resin input pathway 142 and the cation exchange resin input pathway 144 are each directly coupled to the flushing preparation tank 140. The flushing wash preparation tank 140 can be selectively filled with fresh anion exchange resin 112 or fresh cation exchange resin 116. During operation, after fresh resin is directed from the flushing wash preparation tank 140 to either the anion exchange column 120 or the cation exchange column 130, the flushing wash preparation tank 140 can be refilled with either the anion exchange resin 112 or the cation exchange resin 116, depending on whether the anion exchange column 120 or the cation exchange column 130 needs to be replenished next.

[0045] 3 and 4, the waste extraction system 100 includes multiple flushing preparation tanks, such as a first flushing preparation tank 140a fluidly connected to the anion exchange column 120 by an anion exchange resin input line 142 and a second flushing preparation tank 140b fluidly connected to the cation exchange column 130 by a cation exchange resin input line 144. The first flushing preparation tank 140a can be filled with fresh anion exchange resin 112, and the second flushing preparation tank 140b can be filled with fresh cation exchange resin 116. During operation, fresh anion exchange resin 112 can be directed from the first flush preparation tank 140a, for example, along the anion exchange resin input path 142 using the flush pump 182, into the anion exchange column 120, and fresh cation exchange resin 116 can be directed from the second flush preparation tank 140b, for example, along the cation exchange resin input path 144 using the flush pump 182, into the cation exchange column 130.

[0046] 1-4, each flushing wash preparation tank 140 includes one or more loading openings 141 for loading fresh resin into the flushing wash preparation tank 140 and for introducing a pretreatment acid, such as sulfuric acid, into the flushing wash preparation tank 140. The pretreatment acid has a pH comparable to (e.g., within one unit of) that of the initial waste stream. For example, the pretreatment acid may include sulfuric acid, which has a pH of 1. However, it should be understood that other acids may be used as pretreatment acids. For example, the acid used to pretreat the anion exchange resin 112 may have a lower pH than the acid used to pretreat the cation exchange resin 116. By lowering the pH, the anion exchange resin 112 and the cation exchange resin 116 are better suited to adsorbing radionuclides. Pretreating the anion exchange resin 112 and the cation exchange resin 116 forms a slurry that may reduce the difficulty of pumping each resin into the anion exchange column 120 and the cation exchange column 130, respectively. When the anion exchange resin 112 and the cation exchange resin 116 come into contact with certain materials, such as acid, water, or other resin media, the anion exchange resin 112 and the cation exchange resin 116 expand in size. Therefore, by pretreating the anion exchange resin 112 and the cation exchange resin 116, resin expansion can be taken into account when packing the anion exchange column 120 and the cation exchange column 130, ensuring that the anion exchange column 120 and the cation exchange column 130 can be packed in a rational and efficient manner. Furthermore, pretreating the anion exchange resin 112 and the cation exchange resin 116 ensures that the resins are in the chemical form most suitable for adsorbing radionuclides from the waste stream. For example, the anion exchange resin 112 can be pretreated to its chloride form (Cl-), and the cation exchange resin 116 can be pretreated to its sodium form (Na+).

[0047] 1-4 , the waste extraction system 100 further includes a radiation shielding system 110 disposed between the flushing and preparation tank 140 and both the anion exchange column 120 and the cation exchange column 130. During operation, the radiation shielding system 110 forms a radiation barrier between the flushing and preparation tank 140 and both the anion exchange column 120 and the cation exchange column 130. The radiation shielding system 110 may comprise lead, titanium, aluminum, concrete, or a combination thereof. It should be understood that the radiation shielding system 110 may comprise any one or combination of known or yet to be developed radiation shielding materials. By locating the flushing and preparation tank 140 behind the radiation shielding system 110, pretreatment and loading of the anion exchange resin 112 and the cation exchange resin 116 can be performed in a location that is radiologically protected from the radionuclide-containing waste stream. Thus, a radioactive barrier may be placed between personnel loading and pre-treating new anion exchange resin 112 and cation exchange resin 116 and the radionuclide-containing waste stream. In some embodiments, radiation shielding system 110 is a room or compartment that houses flushing preparation tank 140 within waste extraction system 100. In other embodiments, radiation shielding system 110 is a room or compartment that houses components of waste extraction system 100 through which radioactive waste flows, such as anion exchange column 120 and cation exchange column 130.

[0048] 5, a schematic cross-sectional view of an anion exchange column 120 and a cation exchange column 130 is shown. As shown in FIG. 5, in some embodiments, the anion exchange resin 112 includes a plurality of anion exchange resin beads 114, and the cation exchange resin 116 includes a plurality of cation exchange resin beads 118. The anion exchange resin beads 114 and the cation exchange resin beads 118 have an average diameter ranging from 200 μm to 1000 μm, e.g., 400 μm, 425 μm, 450 μm, 475 μm, 500 μm, 525 μm, 550 μm, 575 μm, 600 μm, 625 μm, 650 μm, 675 μm, 700 μm, 725 μm, 750 μm, 775 μm, 800 μm, etc., in the range of 400 μm to 800 μm, or any range having any two of these values ​​as endpoints.

[0049] In some embodiments, the anion exchange resin 112 and the cation exchange resin 116 are each polymer-based. The anion exchange resin 112 can comprise a weakly basic anion exchange resin or a strongly basic anion exchange resin. The cation exchange resin 116 can comprise a strongly acidic cation exchange resin. The anion exchange resin 112 and the cation exchange resin 116 have a combination of porosity, which contributes to adsorption capacity, and chemical functionality, which contributes to selectivity. Furthermore, the cation exchange resin 116 has a preference for adsorption of Cs-137 and Sr-90 relative to uranium, and therefore is effective in the cation exchange column 130, while the anion exchange resin 112 has a preference for adsorption of uranium relative to Cs-137 and Sr-90, and therefore is effective in the anion exchange column 120. Exemplary anion exchange resins 112 include Amberlite™ resin and DIAON™ resin. Exemplary cation exchange resins 116 include SACMP (strong acid cation macroporous polystyrene) resins (such as ResinTech® SACMP manufactured by ResinTech Inc.) and AMP-PAN (ammonium molybdophosphate polyacrylonitrile) resins.

[0050] In some embodiments, the cation exchange resin 116 has a Cs-137 content of 100 mg (i.e., 100 mg / g) to 200 mg / g per gram of cation exchange resin 116, such as in the range of 125 mg / g to 175 mg / g, e.g., 105 mg / g, 110 mg / g, 115 mg / g, 120 mg / g, 125 mg / g, 130 mg / g, 135 mg / g, 140 mg / g, 150 mg / g, 160 mg / g, 170 mg / g, 180 mg / g, 190 mg / g, 200 mg / g, 210 mg / g, 220 mg / g, 230 mg / g, 240 mg / g, 250 mg / g, 260 mg / g, 270 mg / g, 280 mg / g, 290 mg / g, 300 mg / g, 310 mg / g, 320 mg / g, 330 mg / g, 340 mg / g, 350 mg / g, 360 mg / g, 370 mg / g, 380 mg / g, 390 mg / g, 400 mg / g, 410 mg / g, 420 mg / g, 430 mg / g, 440 mg / g, 450 mg / g, 460 mg / g, 470 mg / g, 480 mg / g, 490 mg / g, 500 mg / g, 510 mg / g, 520 mg / g, 530 mg / g, 540 mg / g, 550 mg / g, 560 mg / g, 570 mg / g, 580 mg / g, 590 mg The adsorption capacity of Cs-137 is 145 mg / g, 150 mg / g, 153 mg / g, 155 mg / g, 157 mg / g, 160 mg / g, 165 mg / g, 170 mg / g, 175 mg / g, 180 mg / g, 185 mg / g, 190 mg / g, 195 mg / g, 200 mg / g, or a range having any two of these values ​​as endpoints. In some embodiments, the cation exchange resin 116 has an adsorption capacity of Sr-90 between 0.1 mg (i.e., 0.1 mg / g) and 1 mg / g per gram of cation exchange resin 116, such as in the range of 0.15 mg / g to 0.5 mg / g, for example, 0.15 mg / g, 0.2 mg / g, 0.25 mg / g, 0.3 mg / g, 0.35 mg / g, 0.4 mg / g, 0.45 mg / g, 0.5 mg / g, 0.55 mg / g, 0.6 mg / g, 0.65 mg / g, 0.7 mg / g, 0.75 mg / g, 0.8 mg / g, 0.85 mg / g, 0.9 mg / g, 0.95 mg / g, 1 mg / g, or a range of values ​​having any two of these values ​​as endpoints. Furthermore, in some embodiments, the anion exchange resin 112 has an adsorption capacity of uranium (e.g., U-235) of 85 mg U per gram of anion exchange resin 112 (i.e., 85 mg / g) to 165 mg / g, such as in a range of 115 mg / g to 140 mg / g, for example, 85 mg / g, 90 mg / g, 95 mg / g, 100 mg / g, 105 mg / g, 110 mg / g, 115 mg / g, 120 mg / g, 125 mg / g, 130 mg / g, 135 mg / g, 140 mg / g, 145 mg / g, 150 mg / g, 155 mg / g, 160 mg / g, 165 mg / g, or a range having any two of these values ​​as endpoints.

[0051] 1-5, a method of radionuclide waste extraction using waste extraction system 100 is now described. First, the method comprises directing a waste stream from upstream segment 162 of main waste pathway 160 into anion exchange column 120. Next, the method comprises adsorbing primary radionuclides (e.g., uranium) from the waste stream onto anion exchange resin 112 contained within anion exchange column 120. During operation, the waste stream enters anion exchange column 120 through waste stream input 123, and anion exchange resin 112 contained within anion exchange column 120 adsorbs primary radionuclides present in the waste stream, removing the primary radionuclides from the waste stream. The waste stream then exits anion exchange column 120 through waste stream outlet 125 and flows to cation exchange column 130 with lower levels of target radionuclides than were present in the waste stream upon entry into anion exchange column 120. For example, the anion exchange resin 112 contained in the anion exchange column 120 adsorbs 85% or more of the target radionuclides present in the waste stream, e.g., 86% or more, 87% or more, 88% or more, 89% or more, 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, or a range having any two of these values ​​as endpoints.

[0052] The method then includes directing the waste stream (e.g., the modified waste stream) from the anion exchange column 120 into the cation exchange column 130, for example, along the inter-column segment 165. During operation, the waste stream (e.g., the modified waste stream) flows into the cation exchange column 130 through the waste stream input 134, and the cation exchange resin 116 contained in the cation exchange column 130 adsorbs target radionuclides, such as Sr-90 and Cs-137, present in the modified waste stream. In embodiments including more than one cation exchange column 130, the modified waste stream is then directed into the additional cation exchange columns. During operation, the cation exchange resin 116 contained in the cation exchange column 130 (and any additional cation exchange columns) adsorbs 85% or more of one or more target radionuclides initially present in the waste stream (e.g., present in the waste stream of the upstream segment 162 of the main waste pathway 160), e.g., 85% or more, 90% or more, 92% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, 99.5% or more, 99.9% or more of strontium-90 and cesium-137 present in the modified waste stream, or a range of values ​​having any two of these values ​​as endpoints.

[0053] The modified waste stream then exits cation exchange column 130 through waste stream outlet 135 into inter-column segment 165 of main waste pathway 160. After exiting cation exchange column 130, the waste stream may be directed either to a second cation exchange column (e.g., in embodiments comprising two or more cation exchange columns) or to column waste tank 150 (e.g., in embodiments comprising a single cation exchange column 130, as shown in Figures 1-4). In embodiments comprising a second cation adsorption column, the method comprises adsorbing additional amounts of one or more target radionuclides present in the modified waste stream onto the cation exchange resin contained in the second cation exchange column as the depleted modified waste stream enters the second cation exchange column.

[0054] 1-5 , the method further comprises removing the primary radionuclides from the anion exchange column 120 and directing the primary radionuclides along a strip waste pathway 170. This removal process may comprise directing an elution acid, such as sulfuric acid, into the anion exchange column 120 to desorb uranium from the anion exchange resin 112 to form a primary radionuclide waste stream. The elution acid may be directed from an elution acid source 175 along an eluate pathway 172 through an eluate input 124 into the anion exchange column 120. One or more of pumps 180 may be fluidly coupled to the eluate pathway 172 to serve to facilitate the flow of the elution acid through the eluate pathway 172 and into the anion exchange column 120. During or after this initial elution wash, the primary radionuclide waste stream may be directed from the anion exchange column 120 into a strip waste path 170, where it may be directed to the column waste tank 150 (FIGS. 1 and 3) or to a secondary recovery tank 154 (FIGS. 2 and 4). In some embodiments, for example, the embodiment of FIGS. 2 and 4, the primary radionuclide waste stream containing the uranium desorbed from the anion exchange resin 112 may be recycled back into the medical radioisotope production process. For example, if the waste extraction system 100 is part of a medical isotope production facility, the uranium from the primary radionuclide waste stream may be used to produce additional medical isotopes and then processed by the waste extraction system 100 as part of the waste stream.

[0055] After this first elution acid wash, the method then comprises resuming the step of directing the waste stream from the upstream segment 162 of the main waste pathway 160 into the anion exchange column 120 and then the cation exchange column 130 to adsorb additional primary radionuclides in the anion exchange column 120 and additional target radionuclides in the cation exchange column 130. A second elution acid wash is then performed to remove the adsorbed primary radionuclides from the anion exchange column 120, and the removed primary radionuclides may be directed to the column waste tank 150 or the secondary recovery tank 154. Following the elution acid wash, additional steps of adsorbing primary radionuclides in the anion exchange column 120 and target radionuclides in the cation exchange column 130 may be performed until the anion exchange resin 112 becomes a spent resin. As used herein, "spent resin" refers to an ion exchange resin (e.g., an anion exchange resin or a cation exchange resin) having an adsorption capacity below a threshold percentage of its initial adsorption capacity. The spent resin may have an adsorption capacity of 90% or less of its initial adsorption capacity, for example, 85% or less, 80% or less, 75% or less, 70% or less, 65% or less, 60% or less, or a range of values ​​having any two of these values ​​as endpoints. It should be understood that the threshold percentage for spent resin may vary depending on the radionuclide of interest and the overall composition of the waste stream.

[0056] The method then comprises removing the spent anion exchange resin from the anion exchange column 120 and directing fresh anion exchange resin from a flushing and preparation tank 140 (e.g., the flushing and preparation tank 140 in FIGS. 1 and 2 or the first flushing and preparation tank 140a in FIGS. 3 and 4) into the anion exchange column 120. Removing the spent anion exchange resin from the anion exchange column 120 comprises stopping the flow of the waste stream from the upstream segment 162 of the main waste path 160 into the waste stream input 123 of the anion exchange column 120 and directing the spent anion exchange resin from the anion exchange column 120, for example, along the anion exchange resin outlet path 157 into the spent resin tank 156. Fresh anion exchange resin can then be directed from the flushing and preparation tank 140 into the anion exchange column 120 while the flow of the waste stream from the upstream segment 162 of the main waste path 160 is stopped. After directing fresh anion exchange resin from the flushing and preparation tank 140 into the anion exchange column 120, the flow of the waste stream from the upstream segment 162 of the main waste path 160 into the waste stream input 123 of the anion exchange column 120 can be resumed. In some embodiments, at least three elution acid washes can be performed before removing the spent anion exchange resin and directing fresh anion exchange resin from the flushing and preparation tank 140 into the anion exchange column 120.

[0057] In some embodiments, the method also includes removing the spent cation exchange resin from the cation exchange column 130 and directing new cation exchange resin from the flushing and preparation tank 140 (e.g., the flushing and preparation tank 140 in FIGS. 1 and 2 or the second flushing and preparation tank 140b in FIGS. 3 and 4) into the cation exchange column 130. Removing the spent cation exchange resin from the cation exchange column 130 includes stopping the flow of the waste stream into the waste stream input 134 of the cation exchange column 130 and directing the spent cation exchange resin from the cation exchange column 130, for example, along the cation exchange resin outlet path 159 into the spent resin tank 156. New cation exchange resin can then be directed from the flushing and preparation tank 140 into the cation exchange column 130 while the flow of the waste stream from the waste stream input 134 of the cation exchange column 130 is stopped. After directing new cation exchange resin from the flushing preparation tank 140 into the anion exchange column 120, the flow of the waste stream into the waste stream input 134 of the cation exchange column 130 can be resumed. Because the initial waste stream contains a higher percentage of primary radionuclides than one or more target radionuclides, the anion exchange resin 112 of the anion exchange column 120 is replaced by flushing more frequently than the cation exchange resin 116 of the cation exchange column 130, e.g., two or more times more frequently, three or more times more frequently, four or more times more frequently, etc. In some embodiments, the method further comprises directing the spent resin received by the spent resin tank 156 along the resin waste path 190 to the waste tank 152 for off-site final treatment or removal. As noted above, the final treatment of the spent resin can be solidification in concrete.

[0058] In the embodiments of FIGS. 1 and 3, the modified waste stream from the cation exchange column 130 mixes with the primary radionuclide waste stream from the anion exchange column 120 in the column effluent tank 150. In the embodiments of FIGS. 2 and 4, the column effluent tank 150 receives only the modified waste stream from the cation exchange column 130, as the primary radionuclides are directed to the secondary recovery tank 154. In some embodiments, the method further comprises directing the waste (e.g., the resultant waste) received by the column effluent tank 150 along the waste tank segment 166 to the waste tank 152 for final off-site processing and removal. As noted above, the final processing of the resultant waste may be solidified with concrete to form a solid final waste, which may be performed independently of or in conjunction with the solidification of the spent resin. This results in a denser resultant waste, which contains a lower level of curies per cubic meter than the resultant waste used to form the final waste. Furthermore, the method of radionuclide waste extraction using the waste extraction system 100 described herein is effective in transferring a majority of the target radionuclides such that the final waste formed from the resulting waste retains low levels of radioactivity.

[0059] For example, the resulting waste may contain less than 0.25 Curies per cubic meter of Sr-90, e.g., less than 0.2 Curies per cubic meter, less than 0.15 Curies per cubic meter, less than 0.1 Curies per cubic meter, less than 0.08 Curies per cubic meter, less than 0.06 Curies per cubic meter, less than 0.05 Curies per cubic meter, less than 0.04 Curies per cubic meter, less than 0.03 Curies per cubic meter, less than 0.02 Curies per cubic meter, less than 0.01 Curies per cubic meter, or any value in a range having any two of these values ​​as endpoints. The resulting waste may also contain less than 10 curies per cubic meter of Cs-137, e.g., less than 8 curies per cubic meter, less than 6 curies per cubic meter, less than 5 curies per cubic meter, less than 4 curies per cubic meter, less than 2 curies per cubic meter, less than 1 curie per cubic meter, less than 0.75 curies per cubic meter, less than 0.5 curies per cubic meter, less than 0.25 curies per cubic meter, less than 0.1 curie per cubic meter, or any value in a range having any two of these values ​​as endpoints. In some embodiments, the resulting waste contains less than 0.04 curies per cubic meter of Sr-90 and less than 1 curie per cubic meter of Cs-137. In some embodiments, the final densified waste contains less than 0.04 curies per cubic meter of Sr-90 and less than 1 curie per cubic meter of Cs-137.

[0060] Additionally, the above values ​​of curies per cubic meter in the resulting waste may be used to limit the Sr-90 content of the waste stream if the initial waste stream (i.e., the waste stream passing through the upstream segment 162 of the primary waste pathway 160) has more than 150 curies per cubic meter, e.g., more than 200 curies per cubic meter, more than 300 curies per cubic meter, more than 300 curies per cubic meter, more than 300 curies per cubic meter, more than 500 curies per cubic meter, more than 1000 curies per cubic meter, more than 2500 curies per cubic meter, more than 5000 curies per cubic meter, or a range having any two of these values ​​as endpoints. and any value of Sr-90 in the range, and greater than 44 Curies per cubic meter of Cs-137, e.g., greater than 50 Curies per cubic meter, greater than 100 Curies per cubic meter, greater than 250 Curies per cubic meter, greater than 500 Curies per cubic meter, greater than 800 Curies per cubic meter, greater than 1000 Curies per cubic meter, greater than 1500 Curies per cubic meter, greater than 2000 Curies per cubic meter, greater than 3500 Curies per cubic meter, or any value of Cs-137 in a range having any two of these values ​​as endpoints.

[0061] As used herein, the terms "approximately," "about," "substantially," and similar terms are intended to have broad meanings consistent with common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. Those of ordinary skill in the art reviewing this disclosure should understand that these terms allow for the description of particular features being described and claimed without limiting the scope of those features to precise numerical values ​​or idealized geometries. Accordingly, these terms should be interpreted as indicating that insubstantial or minor variations or modifications of the subject matter described and claimed are considered to be within the scope of the present disclosure as set forth in the following claims.

[0062] As used herein, the term "coupled" and variations thereof refer to the direct or indirect joining of two members to one another. Such joining can be static (e.g., permanent or fixed) or movable (e.g., removable or releasable). Such joining can be achieved when the two members are directly joined to one another, when the two members are joined to one another using a separate intervening member and any additional intermediate members joined to one another, or when the two members are joined to one another using an intervening member integrally formed with one of the two members as a single, unitary body. When "coupled" or variations thereof are modified by additional terms (e.g., directly coupled), the general definition of "coupled" given above is modified by the plain language meaning of the additional terms (e.g., "directly coupled" means joining of two members without any separate intervening members), resulting in a narrower definition than the general definition of "coupled" given above.

[0063] References herein to the location of elements (e.g., "top," "bottom," "upper," "lower") are merely used to describe the orientation of various elements in the drawings. It should be noted that the orientation of various elements may vary according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

[0064] Although the figures and description may indicate a particular order of method steps, the order of such steps may differ from that shown and described unless specified otherwise. Also, two or more steps may be performed concurrently or with partial concurrence unless specified otherwise. Such variations will depend, for example, on the software and hardware systems selected and designer choice. All such variations are within the scope of this disclosure. Similarly, software embodiments of the described methods may be implemented using standard programming techniques with rule-based logic and other logic implementing the various connecting, processing, comparing, and decision steps.

[0065] While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications can be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be used in combination. Accordingly, the following claims are intended to cover all such changes and modifications that are within the scope of the claimed subject matter.

Claims

1. 1. A method for radionuclide waste extraction comprising: directing a waste stream from an upstream segment of a main waste pathway into a waste stream input of an anion exchange column; the waste stream comprises uranium and one or more radionuclides of interest; The anion exchange column contains an anion exchange resin; a cation exchange column containing a cation exchange resin positioned along the primary waste path in fluid communication with and downstream from the anion exchange column; a flushing preparation tank fluidly coupled to the anion exchange column; adsorbing uranium from the waste stream onto an anion exchange resin contained in the anion exchange column; directing the waste stream from the anion exchange column into the cation exchange column; adsorbing one or more target radionuclides onto a cation exchange resin contained in the cation exchange column; removing spent anion exchange resin from the anion exchange column; directing fresh anion exchange resin from the flushing preparation tank into the anion exchange column; A method for providing the above.

2. 10. The method of claim 1, wherein the one or more radionuclides of interest include strontium-90 and cesium-137.

3. 2. The method of claim 1, wherein the anion exchange resin has an initial adsorption capacity and the used anion exchange resin has an adsorption capacity of 85% or less of the initial adsorption capacity.

4. 10. The method of claim 1, further comprising the step of directing the waste stream from the cation exchange column to a column waste tank, wherein the waste stream flowing into the column waste tank comprises less than 0.04 curies per cubic meter of strontium-90 and less than 1 curie per cubic meter of cesium-137.

5. Before removing the used anion exchange resin, directing elution acid into the anion exchange column to desorb uranium from the anion exchange resin in a first elution acid wash to form a uranium waste stream; directing the waste stream from the upstream segment of the main waste pathway into the anion exchange column after the first elution acid wash and allowing uranium to adsorb onto the anion exchange resin; The method of claim 1 further comprising:

6. 6. The method of claim 5, further comprising directing the uranium waste stream from the anion exchange column along a strip waste path to a column waste tank, the strip waste path extending from the anion exchange column to the column waste tank bypassing the cation exchange column.

7. 6. The method of claim 5, further comprising the steps of directing the uranium waste stream from the anion exchange column along a strip path to a secondary recovery tank and directing the waste stream from the cation exchange column to a column waste tank.

8. After the first elution acid wash and prior to removing the spent anion exchange resin, directing the eluted acid into the anion exchange column to desorb uranium from the anion exchange resin in a second eluted acid wash; directing the waste stream from the upstream segment of the main waste pathway into the anion exchange column after the second elution acid wash and allowing uranium to adsorb onto the anion exchange resin; The method of claim 5 further comprising:

9. 6. The method of claim 5, further comprising performing at least three elution acid washes before removing the spent anion exchange resin and directing fresh anion exchange resin from the flushing wash preparation tank into the anion exchange column.

10. The step of removing spent anion exchange resin from the anion exchange column comprises: stopping the flow of the waste stream from the upstream segment of the main waste pathway into the waste stream input of the anion exchange column; directing spent anion exchange resin from the anion exchange column into a spent resin tank; Equipped with directing fresh anion exchange resin from the flushing preparation tank to the anion exchange column occurs while the flow of the waste stream from the upstream segment of the main waste pathway is stopped; 2. The method of claim 1, further comprising the step of directing fresh anion exchange resin from the flushing preparation tank into the anion exchange column, followed by resuming the flow of the waste stream from the upstream segment of the main waste pathway into the waste stream input of the anion exchange column.

11. The flushing preparation tank is fluidly coupled to the cation exchange column, and the method comprises: removing spent cation exchange resin from the cation exchange column; directing fresh cation exchange resin from the flushing preparation tank into the anion exchange column; The method of claim 1 further comprising:

12. The running water cleaning preparation tank is a first running water cleaning preparation tank, removing spent cation exchange resin from the cation exchange column; directing fresh cation exchange resin from a second flushing preparation tank into the cation exchange column; The method of claim 1 further comprising:

13. the waste stream in the upstream segment of the primary waste pathway comprises 1 gram / liter or more of uranium; 10. The method of claim 1, wherein the waste stream in the upstream segment of the main waste pathway comprises a gram / liter level of uranium that is at least 500 times higher than the gram / liter levels of both strontium-90 and cesium-137.

14. 1. A waste extraction system comprising: an anion exchange column containing an anion exchange resin and fluidly coupled to the upstream segment of the primary waste pathway; a cation exchange column containing a cation exchange resin and fluidly coupled to the anion exchange column along the primary waste path, the anion exchange column being upstream from the cation exchange column; a column waste tank disposed downstream of the anion exchange column and the cation exchange column; a flushing preparation tank fluidly coupled to the anion exchange column; a radiation shielding system disposed between the flushing and preparation tank and both the anion exchange column and the cation exchange column, the radiation shielding system forming a radiation barrier between the flushing and preparation tank and both the anion exchange column and the cation exchange column; A waste extraction system comprising:

15. 15. The waste extraction system of claim 14, wherein the flushing wash preparation tank is fluidly connected to the anion exchange column by an anion exchange resin input line, and the flushing wash preparation tank is fluidly connected to the cation exchange column by a cation exchange resin input line.

16. 15. The waste extraction system of claim 14, wherein the flushing preparation tank is a first flushing preparation tank and the waste extraction system comprises a second flushing preparation tank fluidly coupled to the cation exchange column, the first flushing preparation tank containing new anion exchange resin and the second flushing preparation tank containing new cation exchange resin.

17. 15. The waste extraction system of claim 14, further comprising an elution acid source fluidly coupled to the anion exchange column.

18. The anion exchange column a waste stream input and an eluate input, respectively, located at a first end of the anion exchange column, the waste stream input fluidly coupled to the upstream segment of the main waste pathway and the eluate input fluidly coupled to the elution acid source; a waste stream outlet and an eluate outlet, respectively, located at a second end of the anion exchange column, the eluate outlet being fluidly coupled to a strip waste path and the waste stream outlet being fluidly coupled to the cation exchange column; 20. The waste extraction system of claim 17, comprising:

19. 20. The waste extraction system of claim 18, wherein the strip waste path extends from the anion exchange column to the column waste tank, bypassing the cation exchange column.

20. 20. The waste extraction system of claim 18, wherein the strip waste path extends from the anion exchange column to a secondary collection tank.

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