Adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits

Abstract

This invention belongs to the field of uranium hydrometallurgical treatment technology in sandstone uranium mine leaching, specifically relating to an adsorption and resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits. The adsorption and resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits of this invention, based on existing processes, adds the circulating soaking of the adsorption-saturated resin with depleted uranium qualified solution, further increasing the resin capacity and achieving the effect of obtaining a higher quality solution in the next leaching step.

Description

Technical Field

[0001] This invention belongs to the field of uranium hydrometallurgical treatment technology in sandstone uranium mines, specifically relating to an adsorption and resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits. Background Technology

[0002] In the mining process of uranium mines with high chloride and high mineralization sandstone, a neutral CO2+O2 gas leaching process is used for uranium extraction. Uranium ions in the leachate are adsorbed using a weakly basic anion exchange resin. However, with the increasing service life of the resin and the influence of impurities in the leachate, the resin's adsorption capacity gradually decreases, leading to a lower concentration of uranium in the qualified leaching solution. This ultimately reduces the efficiency of the hydrometallurgical process and increases raw material consumption. Therefore, an adsorption-resaturation process is introduced to address the problems of low resin adsorption capacity and low uranium concentration in the qualified leaching solution. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a resin adsorption and resaturation process for weakly basic anion exchange resin under neutral leaching conditions with high chloride and high mineralization, thereby solving the problem of low uranium concentration in the production of qualified liquid due to low resin adsorption capacity.

[0004] The technical solution of the present invention is as follows:

[0005] A process for adsorption and resaturation of anion exchange resin under neutral leaching conditions in sandstone uranium deposits includes the following steps:

[0006] Step 1: Adsorption

[0007] The adsorption process uses two adsorption towers connected in series. The raw liquid flows from the raw liquid pool through the first adsorption tower and the last adsorption tower in sequence, and then flows into the tail liquid pool. Both the first adsorption tower and the last adsorption tower have liquid inlet at the top and liquid outlet at the bottom. When the first adsorption tower is saturated, the first adsorption tower is removed from the adsorption process and transferred to the second resaturation process.

[0008] At this point, a new standby adsorption tower is connected in series after the original adsorption tower to start a new round of adsorption in series between the two towers; in the new round of adsorption process, the adsorption tower of the previous round becomes the adsorption tower of the first round, and the new standby adsorption tower becomes the adsorption tower of the last round.

[0009] Step 2: Resaturation

[0010] For the adsorption tower that has been saturated after step one, i.e. the first adsorption tower, a resaturation treatment is performed.

[0011] The pre-stored depleted uranium solution is placed in the depleted liquid storage tank, and the adsorption tower is connected to the depleted liquid storage tank. The adsorption tower adopts a bottom-in, top-out liquid inlet method, so that the depleted uranium solution circulates between the depleted liquid storage tank and the adsorption tower for re-adsorption. When the uranium concentration at both the inlet and outlet of the adsorption tower is ≤X1g / L (preferably X1=0.1), the circulation is stopped.

[0012] The solution in the adsorption tower is driven into the raw liquid tank by compressed air until it is dried. The resin in the adsorption tower after saturation and re-adsorption is analyzed to determine its uranium content.

[0013] Step 3: Transformation

[0014] For the adsorption tower that has completed the resaturation process in step two, a transformation treatment is carried out;

[0015] The transforming agent is placed in the transforming agent storage tank, and the adsorption tower is connected to the transforming agent storage tank. The adsorption tower adopts a bottom-in, top-out liquid inlet method, so that the transforming agent circulates between the transforming agent storage tank and the adsorption tower to carry out transformation. When the acidity of the inlet and outlet liquid of the adsorption tower reaches the same level and is between X2g / L and X3g / L (preferably X2=13, X3=16), the circulation is stopped and the transformation is completed.

[0016] Step 4: Rinse

[0017] After completing step three, the adsorption tower is ready for use. Once all three adsorption towers are ready, namely the first rinsing tower, the middle rinsing tower, and the last rinsing tower, the rinsing process will begin.

[0018] The eluent is placed in the eluent storage tank; the eluent storage tank is connected to the first eluent tower for three-tower series eluenting, and the eluent in each adsorption tower adopts the top-in, bottom-out method; the liquid output from the last eluent tower is the qualified uranium liquid; when the liquid output from the last eluent tower reaches X4 to X5 cubic meters (preferably X4 = 36, X5 = 38), the eluenting is completed.

[0019] Finally, the first rinsing tower is cut off, and the residual solution in the first rinsing tower is forced into the rinsing agent storage tank by compressed air for the preparation of rinsing agent; after the first rinsing tower is separated, a new round of rinsing process begins; in the new round of rinsing process, the second rinsing tower of the previous round becomes the first rinsing tower of the new round, and the last rinsing tower of the previous round becomes the second rinsing tower of the new round, and then a new adsorption tower that has completed the transformation process in step three is connected as the last rinsing tower.

[0020] Step 5: Washing

[0021] After the adsorption tower has been rinsed, clean water and the tail liquid from the tail liquid tank described in step one are pumped in to wash the solution entrained in the resin of the adsorption tower. The washing liquid, i.e. the effluent from the adsorption tower after washing, enters the raw liquid tank described in step one. When the uranium concentration of the washing liquid is ≤X6mg / L and the pH value is greater than X7 (preferably X6=1, X7=5.0), the washing is completed, and the adsorption tower is used as a backup adsorption tower.

[0022] As a preferred option: Step 1 includes the following operations: The criteria for judging the saturation of the first adsorption tower are: the uranium concentration in the tail liquid of the first adsorption tower is ≥ the uranium concentration in the original liquid, or the uranium concentration in the tail liquid of the last adsorption tower is ≥ 1 mg / L; After the first adsorption tower is separated from the adsorption process, the saturated resin of the first adsorption tower is taken to analyze its uranium content.

[0023] As a preferred option, step two includes the following operations:

[0024] For the adsorption tower that has been saturated after step one, i.e. the first adsorption tower, a resaturation treatment is performed.

[0025] The pre-stored depleted uranium solution has a uranium concentration ≤25.0 g / L; the volume ratio of the depleted uranium solution in the depleted uranium storage tank to the resin in the adsorption tower is 2:1; the adsorption tower is connected to the depleted uranium storage tank, and the adsorption tower adopts a bottom-in, top-out liquid inlet method. The depleted uranium solution is circulated between the depleted uranium storage tank and the adsorption tower by a chemical pump for re-adsorption; after the depleted uranium solution circulates between the depleted uranium storage tank and the adsorption tower for 12 hours, the inlet and outlet liquid of the adsorption tower are taken every 2 hours to determine the uranium concentration. When the uranium concentration of both the inlet and outlet liquid of the adsorption tower is ≤0.1 g / L, the circulation is stopped;

[0026] The solution in the adsorption tower is driven into the raw liquid pool by compressed air until it is dried. The resin in the adsorption tower after saturation and re-adsorption is then analyzed to determine its uranium content.

[0027] As a preferred option, step three includes the following operations:

[0028] For the adsorption tower that has completed the resaturation process in step two, a transformation treatment is carried out;

[0029] Mix qualified liquid with uranium concentration ≤ 8.0 g / L and industrial hydrochloric acid at a volume ratio of 16 m³ / L. 3 3.0~3.5m 3 The conversion agent is prepared in the specified proportions and placed in the conversion agent storage tank. The acidity of the prepared conversion agent is 65 g / L. The adsorption tower is connected to the conversion agent storage tank. The adsorption tower adopts a bottom-in, top-out liquid inlet method. The conversion agent is circulated between the conversion agent storage tank and the adsorption tower by a chemical pump for conversion. After the conversion agent circulates between the conversion agent storage tank and the adsorption tower for 8 hours, when the acidity of the inlet and outlet liquids of the adsorption tower reaches the same level and is between 13.0 g / L and 16.0 g / L, the circulation is stopped, and the conversion is completed.

[0030] As a preferred option, step four includes the following operations:

[0031] After completing step three, the adsorption tower is ready for use. Once all three adsorption towers are ready, namely the first rinsing tower, the middle rinsing tower, and the last rinsing tower, the rinsing process will begin.

[0032] Clean water is used as the eluent and placed in the eluent storage tank. The eluent storage tank is connected to the first eluent tower for three-tower series eluenting. The eluent in each adsorption tower adopts the top-in and bottom-out method, and the eluent inlet linear velocity is controlled at 0.8m / h to 1.0m / h.

[0033] The effluent from the final rinsing tower is the qualified uranium solution: when the uranium concentration of the qualified uranium solution is ≥25.0 g / L, it is considered the finished product; when the uranium concentration of the qualified uranium solution is ≤8.0 g / L and <25.0 g / L, the qualified uranium solution of this concentration is transferred to the lean solution storage tank; when the uranium concentration of the qualified uranium solution is <8.0 g / L, the qualified uranium solution of this concentration is used to prepare the conversion agent; the effluent from the final rinsing tower reaches 36-38 m³. 3 Complete the rinsing process in time;

[0034] Finally, the first rinsing tower is cut off, and the residual solution in the first rinsing tower is forced into the rinsing agent storage tank by compressed air for the preparation of the rinsing agent. After the first rinsing tower is separated, a new round of rinsing process begins. In the new round of rinsing process, the second rinsing tower of the previous round becomes the first rinsing tower of the new round, and the last rinsing tower of the previous round becomes the second rinsing tower of the new round. Then, a new adsorption tower that has completed the transformation process in step three is connected as the last rinsing tower.

[0035] The beneficial effects of this invention are as follows:

[0036] This invention proposes an adsorption resaturation process for anion exchange resin under neutral leaching conditions in sandstone uranium deposits. Under neutral leaching conditions with high chloride and high mineralization, the process achieves resin adsorption resaturation of weakly basic anion exchange resin, solving the problem of low uranium concentration in the production of qualified liquid due to low resin adsorption capacity. The saturated resin capacity and the uranium concentration in the qualified liquid are both increased by more than 50%, and the consumption of raw materials can be reduced by more than 10%. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the adsorption process;

[0038] Figure 1 In the middle, 101-raw liquid tank, 102-adsorption process chemical pump, 103-first tower, 104-last tower, 105-tail liquid tank;

[0039] Figure 2 Schematic diagram of resaturation process and transformation process;

[0040] Figure 2 In the middle, 201-lean liquor storage tank, 202-transformer storage tank, 203-chemical pump for resaturation and transformation process, 204-adsorption tower;

[0041] Figure 3 This is a schematic diagram of the rinsing process;

[0042] Figure 3 In the middle, 301-rinsing agent storage tank, 302-chemical pump, 303-rinsing first tower, 304-rinsing middle tower, 305-rinsing last tower, 306-qualified liquid storage tank;

[0043] Figure 4 This is a schematic diagram of the adsorption tower structure;

[0044] Figure 4 In the middle section, 401-Adsorption tower base, 402-Manhole, 403-Tower body, 404-Compressed air pipe, 405-Leachate inlet, 406-DN40 exhaust valve, 407-Resin, 408-40 mesh screen, 409-Water cap, 410-Quartz sand, 411-Filter plate, 412-Outlet;

[0045] Figure 5 This is a schematic diagram of the eluent storage tank structure;

[0046] Figure 5 In the middle, 501-top tank interface, DN50 flange; 502-top tank interface, DN150 flange; 503-top tank interface, 60cm*70cm; 504-bottom tank interface, DN40 flange.

[0047] Figure 6 Schematic diagram of the structure of the transformation agent storage tank and the qualified liquid storage tank;

[0048] Figure 6 In Chinese: 601-Top tank interface, DN flange; 602-Top tank interface, DN40 flange; 603-Top tank interface, DN600 flange; 604-Bottom tank interface, DN80 flange; 605-Top tank interface, DN80 flange. Detailed Implementation

[0049] The adsorption and resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits according to the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0050] The present invention relates to an adsorption and resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits. Under the conditions of neutral leaching, the existing process is improved by adding a circulating soaking of the adsorbed saturated resin with a qualified depleted uranium solution, which further increases the resin capacity and achieves the effect of leaching out a higher quality solution in the next step.

[0051] The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits of the present invention includes the following steps:

[0052] Step 1: Adsorption.

[0053] like Figure 1 As shown, the adsorption process employs a dense fixed-bed two-adsorption-tower series configuration. The feed solution flows sequentially from the feed solution pool through the first adsorption tower and the last adsorption tower before flowing into the tailings pool. Both the first and last adsorption towers have an inlet and an outlet. When the uranium concentration in the tailings of the first adsorption tower is greater than or equal to the uranium concentration in the feed solution, or when the uranium concentration in the tailings of the last adsorption tower is greater than or equal to 1 mg / L, the first adsorption tower is considered saturated. It is then removed from the adsorption process and transferred to step two, the resaturation process. Simultaneously, the saturated resin from the first adsorption tower is analyzed to determine its uranium content.

[0054] At this point, a new standby adsorption tower is connected in series after the original adsorption terminal tower, starting a new round of adsorption in series between the two towers. In this new round of adsorption, the adsorption terminal tower from the previous round becomes the adsorption head tower, and the new standby adsorption tower becomes the adsorption terminal tower.

[0055] Step 2: Resaturate.

[0056] For the adsorption tower that has been saturated after step one (i.e., the original adsorption tower), a resaturation process is performed.

[0057] like Figure 2 As shown (in the resaturation process), Figure 2 The inlet and outlet valves of the conversion agent storage tank are closed (it does not participate in the circulation). The pre-stored depleted uranium solution (uranium concentration ≤ 25.0 g / L) is placed in the depleted uranium storage tank, with the volume ratio of the depleted uranium solution in the storage tank to the resin in the adsorption tower controlled at approximately 2:1. The adsorption tower is connected to the depleted uranium storage tank, using a bottom-in, top-out feeding method. A chemical pump circulates the depleted uranium solution between the storage tank and the adsorption tower for re-adsorption. After 12 hours of circulation, the inlet and outlet liquids of the adsorption tower are sampled every 2 hours to determine the uranium concentration. Circulation is stopped when the uranium concentrations of both the inlet and outlet liquids are ≤ 0.1 g / L.

[0058] The solution inside the adsorption tower is driven to [the desired state] by compressed air. Figure 1 The original liquid was placed in the pool until it was pressed dry. The resin in the adsorption tower after saturation and re-adsorption was then analyzed to determine its uranium content.

[0059] Step 3: Transformation.

[0060] The adsorption tower that has completed the resaturation process in step two is subjected to a transformation treatment.

[0061] like Figure 2 As shown (in the adsorption process), Figure 2 (The inlet and outlet valves of the lean liquid storage tank are closed, and it does not participate in the circulation.) Add qualified liquid with a uranium concentration ≤ 8.0 g / L and industrial hydrochloric acid at a volume ratio of 16 m³ / L. 3 3.0~3.5m 3 The conversion agent was prepared in a specific ratio and placed in a conversion agent storage tank. The acidity of the prepared conversion agent was 65 g / L. An adsorption tower was connected to the conversion agent storage tank, using a bottom-in, top-out feeding method. A chemical pump circulated the conversion agent between the conversion agent storage tank and the adsorption tower for conversion. After 8 hours of circulation, when the acidity of the influent and effluent of the adsorption tower reached the same level (13.0 g / L to 16.0 g / L), circulation was stopped, and the conversion was complete.

[0062] Step 4: Rinse.

[0063] After completing step three, the adsorption tower is ready for use. Once all three adsorption towers are prepared—namely, the first rinsing tower, the middle rinsing tower, and the last rinsing tower—the rinsing process will begin.

[0064] like Figure 3 As shown, clean water is used as the eluent and placed in the eluent storage tank. The eluent storage tank is connected to the first eluent tower for three-tower series eluenting. The eluent in each adsorption tower adopts the top-in, bottom-out method, and the eluent inlet linear velocity is controlled at 0.8m / h to 1.0m / h.

[0065] The effluent from the final rinsing tower is the qualified uranium solution: when the uranium concentration of the qualified uranium solution is ≥25.0 g / L, it is considered the finished product; when the uranium concentration of the qualified uranium solution is ≤8.0 g / L and <25.0 g / L, this concentration of qualified uranium solution is transferred to the lean solution storage tank; when the uranium concentration of the qualified uranium solution is <8.0 g / L, this concentration of qualified uranium solution is used to prepare the conversion agent. The effluent from the final rinsing tower reaches 36–38 m³. 3 Then, complete the rinsing process.

[0066] Finally, the first rinsing column is cut off, and the residual solution in the first rinsing column is forced into the rinsing agent storage tank using compressed air for rinsing agent preparation. After the first rinsing column is separated, a new round of rinsing begins. In the new round of rinsing, the intermediate rinsing column from the previous round becomes the first rinsing column, and the final rinsing column from the previous round becomes the intermediate rinsing column. Then, a new adsorption column that has completed the transformation process in step three is connected as the final rinsing column.

[0067] Step 5: Washing.

[0068] After the adsorption tower has completed rinsing, pump in 200m... 3 Clear water and 400m 3 The tail liquid in the tail liquid tank described in step one is used to wash the solution entrained in the resin of the adsorption tower. The washing liquid, i.e., the effluent from the adsorption tower after washing, enters the raw liquid tank described in step one. Washing is completed when the uranium concentration of the washing liquid is ≤1mg / L and the pH value is greater than 5.0, and the adsorption tower is used as a backup adsorption tower.

[0069] The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits is implemented using the following existing technology apparatus:

[0070] a. Adsorption tower: such as Figure 4As shown, the adsorption tower is a PO-lined steel tank with a diameter of 2.5m and a total height of 7.5m, with an effective height of 6m. Components include: 401-Adsorption tower base, 402-Manhole, 403-Tower body, 404-Compressed air pipe, 405-Leachate inlet, 406-DN40 exhaust valve, 407-Resin, 408-40 mesh screen, 409-Water cap, 410-Quartz sand, 411-Filter plate, 412-Outlet. The compressed air pipe is a DN40 PE pipe, and the remaining connecting pipes are all PPR pipes, with corresponding dimensions and flange dimensions.

[0071] b. Rinse agent storage tank: such as Figure 5 As shown, the PO tank is made of steel with an inner lining and a diameter of 2.5m, with a height of 2m. The components include: 501 - tank top interface, DN50 flange, connected to the clean water pipeline by DN50 iron pipe; 502 - tank top vent, DN150, connected to the ventilation fan pipeline; 503 - tank top interface, 60cm*70cm, vent; 504 - tank bottom interface, DN40 flange, desorbent outlet, connected to the desorbent delivery pump by DN40 PPR pipe.

[0072] c. Transformation agent (qualified liquid) storage tank: such as Figure 6 As shown, the transformation agent storage tank and the qualified liquid storage tank have the same structure. Both are PO tanks with a diameter of 2.5m and an inner lining of steel, and a height of 4m. The components include: 601 - tank top interface, DN40 flange, connected to the clean water pipeline by a DN40 iron pipe; 602 - tank top interface, DN40 flange, connected to the hydrochloric acid pipeline by a DN40 PPR pipe; 603 - tank top vent, DN600 flange; 604 - tank bottom interface, DN80 flange, used for acidification liquid outlet, connected to a DN80 PPR pipe; 605 - tank top interface, DN80 flange, acidification circulation return water, connected by a DN80 PPR pipe.

[0073] Implementation Results

[0074] After the implementation of this process, the saturated resin capacity and the qualified uranium solution both increased significantly, and the residual uranium capacity of the depleted resin after rinsing was less than 0.8 g / L, which met the requirement of less than 1.0 g / L for the uranium capacity of the subsequent adsorption process.

[0075] Implementation Results: Table 1 shows a comparison of the adsorption process parameters before and after the process improvement based on this invention.

[0076] Table 1: Comparison of process parameters before and after the process improvement according to the present invention

[0077]

[0078] As can be seen from the comparison of parameters between the prior art and the present invention in Table 1, the improved saturated resin capacity and qualified liquid uranium concentration are significantly increased, while the consumption of chemical raw materials per unit is significantly reduced.

[0079] Comparing the processes before and after the improvement, the saturated resin capacity increased by 122.98%, and the uranium concentration in the qualified liquid increased by 69.39%. Due to the significant increase in the qualified liquid uranium concentration after applying the saturated re-adsorption process, the volume of the deprecipitated qualified liquid decreased by 41.67%, hydrochloric acid consumption decreased by 13.11%, and caustic soda consumption decreased by 33.85%. The application of the saturated re-adsorption process did not affect the resin adsorption performance, and all parameters were controlled within the process instructions.

[0080] The application of anion exchange resin adsorption-resaturation technology under neutral leaching conditions in sandstone uranium deposits is also described in detail in the embodiments of this invention. The above embodiments are optimal examples of saturated resorption of uranium hydrometallurgical fixed bed under weakly alkaline neutral leaching conditions. However, under different weakly alkaline anion exchange conditions and different leaching solutions, the control parameters can be varied without departing from the spirit of this invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be within the protection scope of this patent.

Claims

1. A process for adsorption and resaturation of anion exchange resin under neutral leaching conditions in sandstone uranium deposits, characterized in that: Includes the following steps: Step 1: Adsorption The adsorption process uses two adsorption towers connected in series. The raw liquid flows from the raw liquid pool through the first adsorption tower and the last adsorption tower in sequence, and then flows into the tail liquid pool. Both the first adsorption tower and the last adsorption tower have liquid inlet at the top and liquid outlet at the bottom. When the first adsorption tower is saturated, the first adsorption tower is removed from the adsorption process and transferred to the second resaturation process. At this point, a new standby adsorption tower is connected in series after the original adsorption tower to start a new round of adsorption in series between the two towers; in the new round of adsorption process, the adsorption tower of the previous round becomes the adsorption tower of the first round, and the new standby adsorption tower becomes the adsorption tower of the last round. Step 2: Resaturation For the adsorption tower that has been saturated after step one, i.e. the first adsorption tower, a resaturation treatment is performed. The pre-stored depleted uranium solution has a uranium concentration ≤25.0 g / L; the volume ratio of the depleted uranium solution in the depleted uranium storage tank to the resin in the adsorption tower is 2:1; the adsorption tower is connected to the depleted uranium storage tank, and the adsorption tower adopts a bottom-in, top-out liquid inlet method. The depleted uranium solution is circulated between the depleted uranium storage tank and the adsorption tower by a chemical pump for re-adsorption; after the depleted uranium solution circulates between the depleted uranium storage tank and the adsorption tower for 12 hours, the inlet and outlet liquid of the adsorption tower are taken every 2 hours to determine the uranium concentration. When the uranium concentration of both the inlet and outlet liquid of the adsorption tower is ≤0.1 g / L, the circulation is stopped; The solution in the adsorption tower is driven into the raw liquid tank by compressed air until it is dried. The resin in the adsorption tower after saturation and re-adsorption is analyzed to determine its uranium content. Step 3: Transformation For the adsorption tower that has completed the resaturation process in step two, a transformation treatment is carried out; The transforming agent is placed in the transforming agent storage tank, and the adsorption tower is connected to the transforming agent storage tank. The adsorption tower adopts a bottom-in, top-out liquid inlet method, so that the transforming agent circulates between the transforming agent storage tank and the adsorption tower to carry out transformation. When the acidity of the inlet and outlet liquid of the adsorption tower reaches the same level and is between X2g / L and X3g / L, the circulation is stopped and the transformation is completed; X2 = 13, X3 = 16. Step 4: Rinse After completing step three, the adsorption tower is ready for use. Once all three adsorption towers are ready, namely the first rinsing tower, the middle rinsing tower, and the last rinsing tower, the rinsing process will begin. The eluent is placed in the eluent storage tank; the eluent storage tank is connected to the first eluent tower for three-tower series eluenting, and the eluent of each adsorption tower adopts the top-in, bottom-out method; the liquid output of the last eluent tower is the qualified uranium liquid; when the liquid output of the last eluent tower reaches X4 to X5 cubic meters, the eluenting is completed; X4 = 36, X5 = 38. Finally, the first rinsing tower is cut off, and the residual solution in the first rinsing tower is forced into the rinsing agent storage tank by compressed air for the preparation of rinsing agent; after the first rinsing tower is separated, a new round of rinsing process begins; in the new round of rinsing process, the second rinsing tower of the previous round becomes the first rinsing tower of the new round, and the last rinsing tower of the previous round becomes the second rinsing tower of the new round, and then a new adsorption tower that has completed the transformation process in step three is connected as the last rinsing tower. Step 5: Washing After the adsorption tower has been rinsed, clean water and the tailings from the tailings tank described in step one are pumped in to wash the solution entrained in the resin of the adsorption tower; the washing liquid, i.e. the effluent from the adsorption tower after washing, enters the raw liquid tank described in step one; when the uranium concentration of the washing liquid is ≤X6mg / L and the pH value is greater than X7, the washing is completed, and the adsorption tower is used as a standby adsorption tower; X6=1, X7=5.

0.

2. The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits according to claim 1, characterized in that: Step one includes the following operations: The criteria for determining saturation of the first adsorption tower are: the uranium concentration in the tail liquid of the first adsorption tower is greater than or equal to the uranium concentration in the original liquid, or the uranium concentration in the tail liquid of the last adsorption tower is greater than or equal to 1 mg / L.

3. The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits according to claim 1, characterized in that: In step one, after the adsorption tower is separated from the adsorption process, the saturated resin of the adsorption tower is taken to analyze its uranium content.

4. The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits according to claim 1, characterized in that: Step three includes the following operations: For the adsorption tower that has completed the resaturation process in step two, a transformation treatment is carried out; Mix qualified liquid with uranium concentration ≤ 8.0 g / L and industrial hydrochloric acid at a volume ratio of 16 m³ / L. 3 3.0~3.5m 3 The conversion agent is prepared in the specified proportions and placed in the conversion agent storage tank. The acidity of the prepared conversion agent is 65 g / L. The adsorption tower is connected to the conversion agent storage tank. The adsorption tower adopts a bottom-in, top-out liquid inlet method. The conversion agent is circulated between the conversion agent storage tank and the adsorption tower by a chemical pump for conversion. After the conversion agent circulates between the conversion agent storage tank and the adsorption tower for 8 hours, when the acidity of the inlet and outlet liquids of the adsorption tower reaches the same level and is between 13.0 g / L and 16.0 g / L, the circulation is stopped, and the conversion is completed.

5. The adsorption-resaturation process of anion exchange resin under neutral leaching conditions in sandstone uranium deposits according to claim 1, characterized in that: Step four includes the following operations: After completing step three, the adsorption tower is ready for use. Once all three adsorption towers are ready, namely the first rinsing tower, the middle rinsing tower, and the last rinsing tower, the rinsing process will begin. Clean water is used as the eluent and placed in the eluent storage tank. The eluent storage tank is connected to the first eluent tower for three-tower series eluenting. The eluent in each adsorption tower adopts the top-in and bottom-out method, and the eluent inlet linear velocity is controlled at 0.8m / h to 1.0m / h. The effluent from the final rinsing tower is the qualified uranium solution: when the uranium concentration of the qualified uranium solution is ≥25.0 g / L, it is considered the finished product; when the uranium concentration of the qualified uranium solution is ≤8.0 g / L and <25.0 g / L, the qualified uranium solution of this concentration is transferred to the lean solution storage tank; when the uranium concentration of the qualified uranium solution is <8.0 g / L, the qualified uranium solution of this concentration is used to prepare the conversion agent; the effluent from the final rinsing tower reaches 36-38 m³. 3 Complete the rinsing process in time; Finally, the first rinsing tower is cut off, and the residual solution in the first rinsing tower is forced into the rinsing agent storage tank by compressed air for the preparation of the rinsing agent. After the first rinsing tower is separated, a new round of rinsing process begins. In the new round of rinsing process, the second rinsing tower of the previous round becomes the first rinsing tower of the new round, and the last rinsing tower of the previous round becomes the second rinsing tower of the new round. Then, a new adsorption tower that has completed the transformation process in step three is connected as the last rinsing tower.

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