Device and method for reducing content of sulfate radicals in acid leaching uranium hydrometallurgy recovery mother liquor

Abstract

The invention relates to the technical field of acid leaching uranium hydrometallurgy treatment, and particularly discloses a device and a method for reducing the content of sulfate radicals in acid leaching uranium hydrometallurgy recovery mother liquor. The device comprises a mother liquor recovery tank, a gas inlet pipeline, a liquor inlet pipeline, a liquor outlet pipeline and a waste liquor pipeline, and the gas inlet pipeline, the liquid inlet pipeline, the liquid outlet pipeline and the waste liquid pipeline are respectively connected into the mother liquid recovery tank. According to the device and the method, the removal effect of sulfate ions in the precipitation mother liquor is effectively improved, the working quality is improved, and meanwhile, the production cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of acid leaching uranium hydrometallurgical treatment, and particularly relates to a device and method for reducing the sulfate content in the recycle mother liquor of acid leaching uranium hydrometallurgy. Background Art

[0002] During the acid leaching process of in-situ leaching uranium well field, the uranium complex mainly exists as uranyl sulfate ion. Strong basic macroporous anion resin is used for adsorption. After the resin is saturated with adsorption, a desorbent prepared with a certain concentration of industrial sulfuric acid and ammonium nitrate solution is used for desorbing the saturated resin. Since sulfuric acid + ammonium nitrate solution is used for desorbing the uranium-saturated resin, the qualified desorbed solution is acidic, with a pH value between 0.6 and 1.0. The qualified desorbed solution is transported to the precipitation tank by a chemical pump and solid alkali is added for neutral intermittent precipitation. Every 12 hours, the precipitation mother liquor is discharged from the precipitation tank to the mother liquor tank by a self-priming pump for secondary precipitation. When the uranium concentration in the mother liquor in the mother liquor tank is ≤ 10 mg / L, the mother liquor in the mother liquor tank is discharged to the recycle mother liquor pool. Since the sulfuric acid solution + ammonium nitrate process is used for desorbing the saturated resin, the precipitation mother liquor contains relatively high concentrations of nitrate ions and sulfate ions (the content of NO3 - is about 30 g / L, and the content of SO4 2- is about 40 g / L). And ammonium nitrate, as an important component for preparing the desorbent in acid leaching uranium hydrometallurgy, also belongs to an explosive precursor chemical with strict control and difficult procurement. Separating the nitrate ions in the recycle mother liquor is of great significance; while the nitrate ions and sulfate ions in the recycle mother liquor increase in concentration with enrichment. Among them, the content of NO3 - is about 100 g / L, and the content of SO4 2- is about 150 g / L. A large amount of sulfate ions in the recycle mother liquor acting as the desorbent react with the desorbed uranyl nitrate ions to form uranyl sulfate, and the uranyl sulfate is continuously adsorbed by the resin, ultimately affecting the desorption efficiency. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a device and method for reducing the sulfate content in the recycle mother liquor of acid leaching uranium hydrometallurgy in view of the above deficiencies in the prior art, to solve the separation of nitrate ions and sulfate ions in the recycle mother liquor, reduce the sulfate ion concentration, and at the same time ensure that the nitrate ion concentration is not affected.

[0004] To solve the above problems, the technical solution of the present invention is as follows: An apparatus for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy, the apparatus comprising a recovered mother liquor pool, an air inlet pipeline, a liquid inlet pipeline, a liquid outlet pipeline, and a waste liquid pipeline; the air inlet pipeline, the liquid inlet pipeline, the liquid outlet pipeline, and the waste liquid pipeline are respectively connected to the recovered mother liquor pool, the air inlet pipeline includes an air compressor and an air pipe, one end of the air pipe is connected to the air compressor, and the other end is connected to the air-blowing module in the recovered mother liquor pool to provide power for stirring the mother liquor in the recovered mother liquor pool; the liquid inlet pipeline includes a precipitated mother liquor tank and a mother liquor inlet pipe, the precipitated mother liquor tank is connected to the recovered mother liquor pool through the mother liquor inlet pipe to transfer the precipitated mother liquor to the recovered mother liquor pool; the liquid outlet pipeline includes a recovered mother liquor outlet pipe, one end of the recovered mother liquor outlet pipe is connected to the recovered mother liquor pool, and the other end is connected to the desorbent preparation tank to transfer the treated mother liquor in the recovered mother liquor pool to the next process; the waste liquid pipeline includes a waste liquid discharge pipe and an evaporation pond, the evaporation pond is connected to the recovered mother liquor pool through the waste liquid discharge pipe to achieve waste liquid discharge.

[0005] An air pipe valve is provided on the air pipe to control the start and stop of gas input.

[0006] An inlet pipe valve is provided on the mother liquor inlet pipe to control the start and stop of the input of the precipitated mother liquor.

[0007] A mother liquor inlet pipe pump is also provided on the mother liquor inlet pipe to provide the input power of the precipitated mother liquor.

[0008] An outlet pipe valve is provided on the recovered mother liquor outlet pipe to control the start and stop of the output of the treated mother liquor.

[0009] An outlet pipe pump is also provided on the recovered mother liquor outlet pipe to provide the output power of the treated mother liquor.

[0010] A method for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy, the method comprising the following operating steps:

[0011] Step 1: The operator opens the valve from the precipitated mother liquor tank to the inlet pipe and the mother liquor inlet pipe pump, and pumps the mother liquor after secondary precipitation into the recovered mother liquor pool.

[0012] Step 2: When the liquid level in the recovered mother liquor pool is 40 cm from the top of the pool, the operator closes the inlet pipe valve and the mother liquor inlet pipe pump to stop supplementing the mother liquor to the recovered mother liquor pool; take a sample and send it to the laboratory for analysis of NO3 in the mother liquor - and SO4 2- content, calculate the total sulfate ion content in the mother liquor in the recovered mother liquor pool and the amount of quicklime to be added.

[0013] Step 3: Start the air compressor, open the gas pipe valve leading to the recycled mother liquor pool, and agitate the mother liquor by blowing air. The operator evenly scatters quicklime into the recycled mother liquor pool with a long spoon, scattering quicklime while agitating with air, so that the quicklime fully contacts and reacts with the mother liquor;

[0014] Step 4: After agitating the mother liquor in the recycled mother liquor pool with air for 2 hours, turn off the air compressor and the gas pipe valve. After the solution in the recycled mother liquor pool becomes clear for 12 hours, the operator takes a sample and sends it to the laboratory for analysis of the SO4 2- content. If the SO4 2- content ≥ 10 g / L, continue to turn on the air compressor to agitate the mother liquor, add an appropriate amount of quicklime to the recycled mother liquor pool, agitate for 2 hours, let the mother liquor in the recycled mother liquor pool become clear for 12 hours, and take a sample to monitor the SO4 2- content until the SO4 2- content ≤ 10 g / L is considered up to standard;

[0015] Step 5: The operator opens the outlet pipe valve of the recycled mother liquor pool, starts the outlet pipe pump, and pumps the mother liquor in the recycled mother liquor pool into the desorbent preparation tank to add other solutes to prepare the desorbent for desorbing the saturated resin;

[0016] Step 6: After the qualified mother liquor in the recycled mother liquor pool is drained completely, the operator rinses the calcium sulfate precipitate in the recycled mother liquor pool with clean water. The precipitate can be discharged to the evaporation pool through the waste liquid discharge pipe at the bottom of the pool until the recycled mother liquor pool is rinsed clean.

[0017] The remarkable effect of the present invention lies in that: for the device and method for reducing the sulfate content in the acid leaching uranium hydrometallurgy recycled mother liquor described in the present invention, by fully agitating the precipitated mother liquor and quicklime in the device, the sulfate ion concentration in the precipitated mother liquor is effectively reduced without affecting the nitrate ion concentration. The device and method effectively improve the removal effect of sulfate ions in the precipitated mother liquor, improve the working quality, and reduce the production cost at the same time. Description of the Drawings

[0018] Figure 1 is a schematic structural diagram of the device for reducing the sulfate content in the acid leaching uranium hydrometallurgy recycled mother liquor described in the present invention;

[0019] Figure 2 is a flowchart of the method for reducing the sulfate content in the acid leaching uranium hydrometallurgy recycled mother liquor described in the present invention;

[0020] In the figure: 1. Air compressor; 2. Gas pipe valve; 3. Gas pipe; 4. Recycled mother liquor pool; 5. Air blowing module; 6. Mother liquor inlet pipe; 7. Inlet pipe valve; 8. Mother liquor inlet pipe pump; 9. Precipitated mother liquor tank; 10. Recycled mother liquor outlet pipe; 11. Outlet pipe pump; 12. Outlet pipe valve; 13. Desorbent preparation tank; 14. Waste liquid discharge pipe; 15. Evaporation pool. Detailed implementation mode

[0021] The following will clearly and completely describe the technical solutions in the present invention in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts belong to the scope of the present invention.

[0022] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper" is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of description and simplification, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0023] In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, terms such as "connection", "installation", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0025] As Figure 1 shown, a device for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy includes a recovered mother liquor pool 4, an air inlet pipeline, a liquid inlet pipeline, a liquid outlet pipeline, and a waste liquid pipeline;

[0026] The air inlet pipeline, the liquid inlet pipeline, the liquid outlet pipeline, and the waste liquid pipeline are respectively connected to the recovered mother liquor pool 4,

[0027] The air inlet pipeline includes an air compressor 1 and an air pipe 3. One end of the air pipe 3 is connected to the air compressor 1, and the other end is connected to the air bubbling module 5 in the recovered mother liquor pool 4 to provide power for stirring the mother liquor in the recovered mother liquor pool 4;

[0028] The liquid inlet pipeline includes a precipitated mother liquor tank 9 and a mother liquor inlet pipe 6. The precipitated mother liquor tank 9 is connected to the recovered mother liquor pool 4 through the mother liquor inlet pipe 6 to transfer the precipitated mother liquor to the recovered mother liquor pool 4;

[0029] The liquid outlet pipeline includes a recycled mother liquor outlet pipe 10. One end of the recycled mother liquor outlet pipe 10 is connected to a recycled mother liquor pool 4, and the other end is connected to a desorbent preparation tank 13, so as to transfer the mother liquor processed in the recycled mother liquor pool 4 to the next process;

[0030] The waste liquid pipeline includes a waste liquid discharge pipe 14 and an evaporation pond 15. The evaporation pond 15 is connected to the recycled mother liquor pool 4 through the waste liquid discharge pipe 14 to achieve waste liquid discharge.

[0031] As an embodiment, an air pipe valve 2 is provided on the air pipe 3 to control the start and stop of gas input;

[0032] As an embodiment, a feed pipe valve 7 is provided on the mother liquor feed pipe 6 to control the start and stop of the input of the mother liquor after precipitation;

[0033] As an embodiment, a mother liquor feed pipe pump 8 is further provided on the mother liquor feed pipe 6 to provide the input power of the mother liquor after precipitation;

[0034] As an embodiment, an outlet pipe valve 12 is provided on the recycled mother liquor outlet pipe 10 to control the start and stop of the output of the processed mother liquor;

[0035] As an embodiment, an outlet pipe pump 11 is further provided on the recycled mother liquor outlet pipe 10 to provide the output power of the processed mother liquor;

[0036] As Figure 2 shown, a method for reducing the sulfate radical content in the mother liquor recovered from acid leaching uranium hydrometallurgy includes the following operating steps:

[0037] Step 1: The operator opens the feed pipe valve 7 from the precipitation mother liquor tank 9 and the mother liquor feed pipe pump 8, and pumps the mother liquor after secondary precipitation into the recycled mother liquor pool 4;

[0038] Step 2: When the liquid level of the solution in the recycled mother liquor pool is 40 cm from the top of the pool, the operator closes the feed pipe valve 7 and the mother liquor feed pipe pump 8 to stop supplementing the mother liquor to the recycled mother liquor pool 4. Take a sample and send it to the laboratory for analysis of NO3 - and SO4 2- contents, calculate the total sulfate radical ion content of the mother liquor in the recycled mother liquor pool 4 and the amount of quicklime to be added;

[0039] Step 3: Start the air compressor 1, open the air pipe valve 2 leading to the inside of the recycled mother liquor pool 4, and agitate the mother liquor by blowing air. The operator evenly scatters quicklime into the recycled mother liquor pool 4 with a long spoon, scattering quicklime while stirring with air to allow the quicklime to fully contact and react with the mother liquor;

[0040] Step 4: After air agitation of the mother liquor in the mother liquor recovery tank 4 for 2 hours, turn off the air compressor 1 and the air pipe valve 2. After the solution in the mother liquor recovery tank 4 becomes clear for 12 hours, the operator takes a sample and sends it to the laboratory for analysis of the SO4 2- content. If the SO4 2- content ≥ 10 g / L, continue to turn on the air compressor 1 to aerate and stir the mother liquor, add an appropriate amount of quicklime to the mother liquor recovery tank 4, stir for 2 hours, let the mother liquor in the mother liquor recovery tank 4 become clear for 12 hours, and take a sample to monitor the SO4 2- content. It is regarded as meeting the standard until the SO4 2- content ≤ 10 g / L;

[0041] Step 5: The operator opens the liquid outlet pipe valve 12 of the mother liquor recovery tank 4, starts the liquid outlet pipeline pump 11, and pumps the mother liquor in the mother liquor recovery tank 4 into the desorbent preparation tank 13 to add other solutes to prepare the desorbent for desorbing the saturated resin;

[0042] Step 6: After the qualified mother liquor in the mother liquor recovery tank 4 is drained completely, the operator rinses the calcium sulfate precipitate in the mother liquor recovery tank 4 with clean water. The precipitate can be discharged to the evaporation pond 15 through the waste liquid discharge pipe 14 at the bottom of the pond until the mother liquor recovery tank 4 is rinsed clean.

[0043] The purpose of the present invention is to overcome the defects of the existing uranium hydrometallurgy technology, and provide an apparatus and method for reducing the sulfate content in the mother liquor recovered from acid leaching uranium hydrometallurgy. The apparatus and method mainly concentrate the precipitated mother liquor in the mother liquor recovery tank. In winter, the local natural climate with relatively low temperature can be utilized, and the sulfate ions in the mother liquor are crystallized and removed in the form of sodium sulfate molecules. However, in summer, due to the high temperature, the sulfate in the mother liquor is dissolved in the mother liquor in the form of ions and is not easily removed. Therefore, a mother liquor recovery tank is designed. The bottom and the surrounding of the tank are both laid with anti-seepage soft PVC materials, and a sewage discharge pipe is installed at the bottom of the tank and connected to the evaporation pond. An air injection pipe is installed in the tank, quicklime is evenly sprinkled, and air is injected into the mother liquor recovery tank through the air pipe for agitation, so that the sulfate in the mother liquor fully reacts with the quicklime sprinkled, generating calcium sulfate precipitate, which can effectively reduce the sulfate in the mother liquor from 150 g / L to below 10 g / L, while the concentration of nitrate ions in the mother liquor is hardly affected, realizing the separation of nitrate ions and sulfate ions in the mother liquor, and the desorption efficiency of the mother liquor returned as the desorbent is basically the same as that of the newly prepared desorbent.

[0044] In the present invention, quicklime is put into the mother liquor recovery tank, and air is blown into the mother liquor through an air pipe for stirring, so that sulfate radicals in the mother liquor fully react with quicklime to form calcium sulfate precipitation. After natural clarification, the supernatant of the mother liquor is drawn out. The sulfate radicals in the recovered mother liquor can be effectively reduced from 150 g / L to below 10 g / L, while the concentration of nitrate ions in the recovered mother liquor is hardly affected, realizing the separation of nitrate ions and sulfate radicals in the recovered mother liquor. The desorption efficiency of the recovered mother liquor returned as a desorbent is basically the same as that of the newly prepared desorbent.

[0045] Implementation results:

[0046] The comparison of the parameters of the mother liquor obtained by the device and method for reducing the sulfate content in the acid leaching uranium hydrometallurgy recovered mother liquor of the present invention with those of the untreated mother liquor is shown in Tables 1 and 2:

[0047] Table 1: Comparison of the parameters of two kinds of mother liquors

[0048]

[0049] Table 2: Comparison of the data of the desorption qualified solution prepared by the recovered mother liquor and the desorbent prepared with clear water

[0050]

[0051] As can be seen from Tables 1 and 2, after the recovered mother liquor is treated by the process of reducing sulfate radicals, the content of SO4 2- in the mother liquor is reduced from about 150 g / L to below 10 g / L. The uranium concentration of the desorption saturated resin qualified solution prepared with the recovered mother liquor as the desorbent is basically the same as that prepared with clear water, meeting the standard of using the recovered mother liquor as the desorbent.

[0052] Inspired by the ideal embodiments of the present invention described above, through the above description, relevant staff can make various changes and modifications completely within the scope of not deviating from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An apparatus for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy, characterized in that: The device includes a recycled mother liquor pool (4), an air inlet pipeline, a liquid inlet pipeline, a liquid outlet pipeline, and a waste liquid pipeline; the air inlet pipeline, the liquid inlet pipeline, the liquid outlet pipeline, and the waste liquid pipeline are respectively connected to the recycled mother liquor pool (4). The air inlet pipeline includes an air compressor (1) and an air pipe (3). One end of the air pipe (3) is connected to the air compressor (1), and the other end is connected to the air bubbling module (5) in the recycled mother liquor pool (4) to provide power for stirring the mother liquor in the recycled mother liquor pool (4). The liquid inlet pipeline includes a precipitated mother liquor tank (9) and a mother liquor inlet pipe (6). The precipitated mother liquor tank (9) is connected to the recycled mother liquor pool (4) through the mother liquor inlet pipe (6) to transfer the precipitated mother liquor to the recycled mother liquor pool (4). The liquid outlet pipeline includes a recycled mother liquor outlet pipe (10). One end of the recycled mother liquor outlet pipe (10) is connected to the recycled mother liquor pool (4), and the other end is connected to a desorbent preparation tank (13) to transfer the mother liquor processed in the recycled mother liquor pool (4) to the next process. The waste liquid pipeline includes a waste liquid discharge pipe (14) and an evaporation pond (15). The evaporation pond (15) is connected to the recycled mother liquor pool (4) through the waste liquid discharge pipe (14) to discharge waste liquid.

2. The device for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy according to claim 1, wherein: An air pipe valve (2) is provided on the air pipe (3) to control the start and stop of gas input.

3. The device for reducing the sulfate content in the mother liquor of uranium hydrometallurgical recovery by acid leaching according to claim 1, characterized in that: A liquid inlet pipe valve (7) is provided on the mother liquor inlet pipe (6) to control the start and stop of the input of the precipitated mother liquor.

4. An apparatus for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy according to claim 1, characterized in that: A mother liquor inlet pipe pump (8) is also provided on the mother liquor inlet pipe (6) to provide the input power of the precipitated mother liquor.

5. The device for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy according to claim 1, wherein: An outlet pipe valve (12) is provided on the recycled mother liquor outlet pipe (10) to control the start and stop of the output of the processed mother liquor.

6. The device for reducing the sulfate content in the mother liquor of uranium hydrometallurgical recovery by acid leaching according to claim 1, characterized in that: An outlet pipe pump (11) is also provided on the recycled mother liquor outlet pipe (10) to provide the output power of the processed mother liquor.

7. A method for reducing the sulfate content in the mother liquor recovered by acid leaching uranium hydrometallurgy, characterized in that: The method includes the following operating steps: Step 1: The operator opens the liquid inlet pipe valve (7) from the precipitated mother liquor tank (9) and the mother liquor inlet pipe pump (8), and pumps the mother liquor after secondary precipitation into the recycled mother liquor pool (4). Step 2: When the liquid level of the solution in the mother liquor pond to be recycled is 40 cm from the top of the pond, the operator closes the inlet pipe valve (7) and the mother liquor inlet pipeline pump (8) to stop supplementing the mother liquor to the recycled mother liquor pond (4); take a sample and send it to the laboratory for analysis of NO3 - and SO4 2- content, calculate the total sulfate ion content of the mother liquor in the recycled mother liquor pond (4) and the amount of quicklime to be put in; Step 3: Start the air compressor (1), open the air pipe valve (2) leading to the inside of the recycled mother liquor pool (4), and agitate the mother liquor by bubbling. The operator evenly sprinkles quicklime into the recycled mother liquor pool (4) with a long spoon, and sprinkles quicklime while stirring with air to allow the quicklime to fully contact and react with the mother liquor. Step 4: After air-stirring the mother liquor in the mother liquor recovery tank (4) for 2 hours, turn off the air compressor (1) and the air pipe valve (2). After the solution in the mother liquor recovery tank (4) has been clarified for 12 hours, the operator takes a sample and sends it to the laboratory for SO4 analysis. 2- Content. If the SO4 2- content ≥ 10 g / L, continue to turn on the air compressor (1) to aerate and stir the mother liquor, add an appropriate amount of quicklime to the mother liquor recovery tank (4), stir for 2 hours, clarify the mother liquor in the mother liquor recovery tank (4) for 12 hours, and take a sample to monitor the SO4 2- content. Until the SO4 2- content ≤ 10 g / L is considered up to standard. Step 5: The operator opens the outlet pipe valve (12) of the recycled mother liquor pool (4), starts the outlet pipe pump (11), and pumps the mother liquor in the recycled mother liquor pool (4) into the desorbent preparation tank (13) to add other solutes to prepare the desorbent and desorb the saturated resin. Step 6: After the qualified mother liquor in the recycled mother liquor pool (4) is drained, the operator rinses the calcium sulfate precipitate in the recycled mother liquor pool (4) with clean water. The precipitate can be discharged to the evaporation pond (15) through the waste liquid discharge pipe (14) at the bottom of the pool until the recycled mother liquor pool (4) is rinsed clean.

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