P507 Method and apparatus for extracting lithium carbonate for batteries from raffinate

Abstract

P507 A method and apparatus for extracting lithium carbonate for batteries from raffinate is provided, and non-ferrous metals This technology belongs to the field of hydrometallurgy, and is particularly concerned with lithium ion extraction, purification, concentration and crystallization technology. Impurity adjustment, extraction, purification, back-extraction, alkalinization, crystallization, separation, base, etc. In the impurity adjustment, first, the P507 raffinate is treated with lithium hydroxide. Adjust the pH value to 8.5-10.5 using alcohol or alkali, filter, and prepare the filtrate for use. In the alkalinization, the lithium solution is heated to 85 to 95°C and lithium hydroxide is added. Or add alkali to adjust the pH value to 9.0-13.0, keep at 85-95℃ for 2-4 hours. After standing for 8 hours, the mixture was filtered and the filtrate was used. After that, compressed air is injected into the filtrate at a compressed air pressure of 0.2 to 0.8 MPa and a compressed air flow rate of 8 to 30 m 3 / h, evaporative concentration is performed, and when fine crystals form in the concentrated liquid, the material is discharged. The lithium content in the extracted raffinate is less than 1 mg / L. The difficulty of wastewater treatment is reduced, and lithium can be extracted through processes such as impurity adjustment, extraction, purification, and back extraction. The solution is highly purified, alkalized, crystallized, separated and base-based, and the resulting lithium carbonate is The yield is over 99%, and the purity of the product meets the requirements for batteries.

Description

[Technical Field]

[0001] The present invention relates to the technical field of hydrometallurgy of non-ferrous metals, in particular to the extraction, purification and concentration of lithium ions Concerning the technology of crystallization. [Background technology]

[0002] When the positive electrode material of a lithium-ion battery is subjected to wet recovery processing, it is extracted using P507 extractant. In this case, the extract contains more than 1 g / L of lithium. The yield is obtained by precipitation using trisodium phosphate and carbonate, and lithium phosphate and lithium carbonate are obtained. The lithium phosphate or lithium carbonate produced by this method The overall yield of lithium ion precipitation is generally 70-90%. The lithium ion concentration in the solution after precipitation is still 20 The level is about 0 mg / L, and treatment must continue after that, with consideration given to recovery and the environment. Therefore, there is a need for the production of high-quality lithium carbonate and environmentally friendly processing. To meet the demand, improve the lithium recovery yield and product quality in P507 extract. Methods and equipment need to be researched. Summary of the Invention [Problem to be solved by the invention]

[0003] The object of the present invention is to overcome the drawbacks and deficiencies described in the background art above and to increase the recovery rate of lithium. The recovered lithium carbonate can be used in batteries and can be recycled and processed. The lithium content of the raffinate after treatment is less than 1 mg / L, and it is treated in an environmentally friendly manner. The difficulty of producing lithium carbonate for batteries from P507 raffinate can be significantly reduced. A brewing method and brewing device are disclosed. [Means for solving the problem]

[0004] One of the technical solutions of the present invention is to adjust impurities, extract, purify, back-extract, alkalize, crystallize Extraction of battery-grade lithium carbonate from P507 raffinate including precipitation, separation, and base steps A method for extracting a liquid, comprising: In the above-mentioned impurity adjustment, first, the P507 raffinate is treated with lithium hydroxide or ammonium hydroxide. Adjust the pH to 8.5-10.5, preferably 9-10, or 9.5, using potassium hydroxide, and filter. The filtrate is then used. In the extraction, the saponified P507 was mixed with the liquid filtered in the impurity adjustment step. After that, the mixture was left to stand and the phases were separated. The P507 organic phase was left, and the aqueous phase was analyzed for lithium ion concentration. If it is less than 1 mg / L, the wastewater is treated. In the purification, the organic phase in the extraction step is 0.1 to 0.25 mol / L, preferably After purifying and washing with a 0.2 mol / L lithium sulfate solution, the mixture is left to stand and the phases are separated. P507 The organic phase was kept and the aqueous phase was used for extraction. In the back-extraction, the purified and washed P507 organic phase was back-extracted with dilute sulfuric acid, and the two phases were separated. To obtain a blank organic and lithium sulfate solution, In the alkalinization, the lithium solution obtained in the stripping step is heated at 85 to 95°C, preferably Preferably, the temperature is raised to 90°C, and lithium hydroxide or an alkali is added to adjust the pH value to 9.0 to 13. 0, preferably 10.0 to 12.0, or 10.5 to 11.0, and Preferably, the mixture is kept at 90°C for 2 to 8 hours, more preferably 3 to 7 hours, 4 to 6 hours, or 3 to 5 hours. After leaving it for 4 hours, it is filtered and the filtrate is used. In the crystallization, after alkalizing, compressed air is injected into the filtrate at a compressed air pressure of 0.2 to 0. 8MPa, preferably 0.3-0.7MPa, 0.4-0.6MPa, 0.5MPa, pressure Compressed air flow rate: 8~30m 3 / h, preferably 10 to 25 m 3 / h, 13-22m 3 / h, 1 5 to 20 m 3 / h, 16-18m 3 / h, evaporation and concentration are carried out, and fine particles are added to the concentrated liquid. Once the crystal grains are formed, the material is discharged and cooled.

[0005] Furthermore, in the back-extraction, the P507 organic phase after purification and washing is back-extracted with dilute liquid alkali. The phases may then be separated to obtain blank organic and lithium hydroxide solutions.

[0006] Another technical solution of the present invention is: A stirring chamber is provided, and the stirring chamber is connected to the clarification chamber through a transition tank, and an agitator is provided in the stirring chamber. An extraction apparatus for extracting lithium carbonate for batteries from P507 raffinate, comprising: The stirring chamber is cubic, the fining chamber is rectangular, and the aspect ratio of the fining chamber is 4-5:1. The volume ratio of the stirring chamber to the clarification chamber is 1:4.5 to 5.5, and the agitators are a main agitator and a secondary agitator. The main agitator has a two-layered "cross"-shaped agitator blade, and the secondary agitator The agitator is a cylindrical agitator, and the cylindrical agitator has a diameter of 5 to 10 mm. The circular holes of 100mm are evenly distributed, and the stirring blades are fitted into the cylindrical stirring body. It is a sign.

[0007] Furthermore, the rotation speed of the main agitator is 1000 to 2000 rpm, preferably 1200 to 1 800 rpm, 1300-1600 rpm, 1400-1500 rpm, The rotation speed of the agitator 2 is 100 to 200 rpm, preferably 120 to 180 rpm, 0 to 160 rpm, 150 rpm.

[0008] Furthermore, the diameter of the stirring blade of the main stirrer is 0.28 to 0.33 of the side length of the stirring chamber, The diameter of the cylindrical stirring body for secondary stirring is 0.65 to 0.75 of the side length of the stirring chamber.

[0009] Furthermore, the cylindrical wall has one circular hole per square centimeter.

[0010] Furthermore, two strip-shaped stabilizing fences are installed in the fining chamber in sequence, and the transition of the fining chamber The distance of the first stabilization fence from the inlet end of the tank is 1 / 2 the length of the clarification chamber. 4. The second stabilization fence is positioned in the longitudinal direction of the clarifier chamber, and the clarifier chamber transition tank is The distance from the inlet end of the fining chamber is half the length of the fining chamber. [Effects of the Invention]

[0011] The present invention adopts the above technical solutions and has the following advantages: (1) By adopting the above extraction method, the lithium ion concentration in the raffinate is 1m g / L, significantly reducing the difficulty of wastewater treatment. (2) The lithium recovery rate is improved by adopting the extraction method and alkalinization-air precipitation method. This allows for a lithium recovery rate of over 99%. (3) The extraction separation method was used to increase the purity of the lithium salt solution, so that the lithium carbonate in the precipitation This ensures that the quality of the aluminum products meets the requirements for batteries. (4) By adopting the alkalinization-air precipitation method, the contamination of impurity ions is avoided, and By ensuring and improving the purity of the product, the lithium carbonate product fully meets the requirements for batteries. It is satisfied.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

[0013] 1 - Main agitator, 2 - Sub - agitator, 3 - Cylindrical agitator, 4 - Agitating blade, 5 - Agitating chamber, 6 - Transition Tank, 7 - Clarification chamber, 8 - Stabilization fence, 9 - Sub - agitator transmission wheel, 10 - Sub - agitator driving wheel , 11 - Sub - agitator driving motor, 12 - Main agitator driving motor Best Mode for Carrying Out the Invention

[0014] The method for extracting lithium carbonate for batteries from P507 raffinate includes impurity adjustment, extraction, purification , back - extraction, alkalization, crystallization, separation, and base steps. In the said impurity adjustment, first, the pH value of the P507 raffinate is adjusted to 10.0 using lithium hydroxide or an alkali, filtered, and the filtrate is used. In the said extraction, the saponified P507 is mixed with the liquid filtered in the impurity adjustment step and then left to stand for phase separation, leaving the P507 organic phase. For the aqueous phase, the lithium ion concentration is detected. If it is less than 1 mg / L, it is subjected to wastewater treatment. In the said purification, the organic phase obtained in the extraction step is treated with a 0.2 mol / L lithium sulfate solution After purification and washing, let it stand for phase separation, leave the P507 organic phase, and use the aqueous phase for extraction. In the reverse extraction, the P507 organic phase after purification and washing is reverse extracted with dilute sulfuric acid, and the two phases are separated. to obtain blank organic and lithium sulfate solution. In the alkalization, the lithium solution obtained in the reverse extraction step is heated to 90 °C. Then, lithium hydroxide or alkali is added to adjust the pH value to 10.0, and it is kept warm at 90 °C. After standing for 4 hours, filter it, and use the filtrate. In the crystallization, after alkalization, compressed air is introduced into the filtrate at a compressed air pressure of 0.5 MPa. a, and evaporation concentration is carried out while introducing at a compressed air flow rate of 18 m. 3 / h. When fine crystal grains are generated, discharge the material and cool it.

[0015] In the reverse extraction, the P507 organic phase after purification and washing is reverse extracted with dilute liquid alkali, and the two phases are separated to obtain blank organic and lithium hydroxide solution.

[0016] In an extraction device for extracting lithium carbonate for batteries from P507 raffinate provided with a stirring chamber, the stirring chamber is connected to a clarification chamber through a transition tank, and a stirrer is provided in the stirring chamber. The stirring chamber is cubic, the clarification chamber is rectangular parallelepiped, the aspect ratio of the clarification chamber is 5:1, and the volume ratio of the stirring chamber to the clarification chamber is 1:5.5. The stirrer consists of a main stirrer and a sub-stirrer. The stirring blades provided on the main stirrer are configured in a two-layer "cross" shape, and the stirring body of the sub-stirrer is a circular cylindrical stirring body. Circular holes with a diameter of 5 mm are evenly distributed on the cylinder wall of the cylindrical stirring body. The stirring blades are fitted into the cylindrical stirring body.

[0017] Preferably, the rotation speed of the main stirrer is 1200 revolutions per minute, and the rotation speed of the sub-stirrer 2 is 150 revolutions. is in revolutions per minute.

[0018] Preferably, the diameter of the stirring blades of the main stirrer is 0.3 times the side length of the stirring chamber, and for the secondary stirring the diameter of the cylindrical stirring body is 0.7 times the side length of the stirring chamber.

[0019] Preferably, one circular hole is provided per square centimeter on the cylindrical wall.

[0020] Preferably, two strip-shaped stabilizing fences are sequentially provided in the clarification chamber. The distance from the inlet end of the transition tank of the clarification chamber to the position of the first stabilizing fence is 1 / 4 of the length of the clarification chamber, and the distance from the inlet end of the transition tank of the clarification chamber to the position of the second stabilizing fence in the length of the clarification chamber is 1 / 2 of the length of the clarification chamber. 1 / 4, and the distance from the inlet end of the transition tank of the clarification chamber to the position of the second stabilizing fence in the length of the clarification chamber is 1 / 2 of the length of the clarification chamber. is 1 / 2 of the length of the clarification chamber. Examples

[0021] To more clearly explain the present invention, specific embodiments will be used below with reference to FIGS. 1 to 4 to further explain the present invention.

[0022] Embodiment 1: As shown in FIG. 1, the method for extracting lithium carbonate for batteries from P507 raffinate includes impurity adjustment, extraction, purification, back-extraction, alkalization, crystallization, separation, and base steps and is characterized in that in the impurity adjustment, first, the pH value of the P507 raffinate is adjusted to 8.5 to 10.5 using lithium hydroxide or an alkali, filtered, and the filtrate is used. This is the feature.

[0023] When adjusting the pH value using lithium hydroxide or an alkali as described above, it may be adjusted to 9 to 10, 8.5 to 9, 9 to 9.5, or 9.5 to 10. This step can effectively precipitate and remove cations of impurities such as nickel, and the experimental data are shown in Table 1. It can be done, and the experimental data are shown in Table 1.

[0024] Table 1: Table showing the effect of pH value on the precipitation and removal of impurity cations such as nickel TIFF0007716146000001.tif52145

[0025] In the extraction, in the extraction device, the saponified P507 is filtered in the impurity adjustment step and then mixed with the liquid, and then left standing to separate the phases, leaving the P507 organic phase. For the aqueous phase, the lithium ion concentration is detected. If it is less than 1 mg / L, it is used for wastewater treatment. After being mixed with the filtered liquid in the impurity adjustment step, it is left standing to separate the phases, leaving the P507 organic phase. For the aqueous phase, the lithium ion concentration is detected. If it is less than 1 mg / L, it is used for wastewater treatment. After being mixed with the filtered liquid in the impurity adjustment step, it is left standing to separate the phases, leaving the P507 organic phase. For the aqueous phase, the lithium ion concentration is detected. If it is less than 1 mg / L, it is used for wastewater treatment.

[0026] This step can extract lithium in the filtrate into the organic phase, reduce the lithium ion concentration in the raffinate, and reduce the difficulty of wastewater treatment. This step can extract lithium in the filtrate into the organic phase, reduce the lithium ion concentration in the raffinate, and reduce the difficulty of wastewater treatment.

[0027] In the purification, in the extraction device, the organic phase obtained in the extraction step is purified and washed with a lithium sulfate solution of 0.1 - 0.25 mol / L, and then left standing to separate the phases, leaving the P507 organic phase, and the aqueous phase is used for extraction. In the purification, in the extraction device, the organic phase obtained in the extraction step is purified and washed with a lithium sulfate solution of 0.1 - 0.25 mol / L, and then left standing to separate the phases, leaving the P507 organic phase, and the aqueous phase is used for extraction. In the purification, in the extraction device, the organic phase obtained in the extraction step is purified and washed with a lithium sulfate solution of 0.1 - 0.25 mol / L, and then left standing to separate the phases, leaving the P507 organic phase, and the aqueous phase is used for extraction. The above lithium sulfate solution may be 0.12 - 0.23 mol / L, 0.15 - 0.20 mol / L, 0.16 - 0.18 mol / L, 0.1 - 0.12 mol / L, 0.13 - 0.15 mol / L, 0.16 - 0.18 mol / L, 0.19 - 0.20 mol / L, 0.21 - 0.22 mol / L, 0.23 - 0.25 mol / L. / L, 0.16 - 0.18 mol / L, 0.19 - 0.20 mol / L, 0.21 - 0.22 mol / L, 0.23 - 0.25 mol / L. 5 mol / L, 0.16 - 0.18 mol / L, 0.19 - 0.20 mol / L, 0.21 - 0.22 mol / L, 0.23 - 0.25 mol / L. 1 - 0.22 mol / L, 0.23 - 0.25 mol / L.

[0028] This step can wash the impurity ions such as sodium mixed in the organic phase and increase and purify the lithium ions in the organic phase. The experimental data are shown in Table 2. This step can wash the impurity ions such as sodium mixed in the organic phase and increase and purify the lithium ions in the organic phase. The experimental data are shown in Table 2.

[0029] Table 2: Effect of lithium sulfate solution concentration on impurity ion removal TIFF0007716146000002.tif47147

[0030] In the back-extraction, the P507 organic phase after purification and washing is back-extracted with dilute sulfuric acid in the extractor. , and the two phases were separated to obtain a blank organic layer and a lithium sulfate solution. This step allows for back-extraction of the lithium in the organic phase to obtain the lithium salt in solution. This increases the lithium ion concentration while further separating lithium from impurities.

[0031] In the alkalinization, the lithium solution obtained in the stripping step is heated to 85 to 95°C. Heat the water, add lithium hydroxide or alkali to adjust the pH to 9.0-13.0, and then After keeping the temperature at 95°C and leaving it to stand for 2 to 8 hours, the mixture is filtered and the filtrate is ready for use.

[0032] The above lithium solution is stored at 85-86℃, 87-88℃, 89-90℃, 91-92℃, and 9 The temperature may be raised to 3 to 94°C.

[0033] By adding the above lithium hydroxide or alkali, the pH value can be adjusted to 9.5-10.0, 10. It may also be adjusted to 5~11.0, 11.5~12.0, or 12.5~13.0.

[0034] The above temperatures are 85-86℃, 87-88℃, 89-90℃, 91-92℃, 93- It may be 94°C.

[0035] The above-mentioned standing time may be 2 to 3 hours, 4 to 5 hours, or 6 to 7 hours. This alkalinization step alkalizes the lithium ions and removes organic impurities in the lithium solution. The experimental data are shown in Tables 3, 4, and 5. do.

[0036] Table 3: Organic content of lithium solution at each reaction temperature under the condition of pH 11.0 and standing for 4 hours Table of amount and removal effect TIFF0007716146000003.tif54141

[0037] Table 4: Organic content and pH of lithium solution at 90℃ for 4 hours and removal effect table TIFF0007716146000004.tif59148

[0038] TIFF0007716146000005.tif54138

[0039] In the crystallization, after alkalizing, compressed air is blown into the filtrate at a compressed air pressure of 0.2 to 0 .8MPa, compressed air flow rate 8~30m 3 / h, evaporation and concentration are carried out, and the concentrated solution is Once fine grains are produced, the material is discharged and cooled.

[0040] The above compressed air pressures are 0.2-0.3MPa, 0.4-0.5MPa, 0.6-0.7MPa It may be MPa.

[0041] The above compressed air flow rate is 8 to 10 m 3 / h, 11-13m 3 / h, 14-16m 3 / h, 17~19m 3 / h, 20-22m 3 / h, 23-25m 3 / h, 26-28m 3 / h, 29~30m 3It may also be / h.

[0042] In this crystallization step, lithium ions can be carbonized to convert lithium into lithium carbonate by the action of carbon dioxide in compressed air. The experimental data are shown in Table 6 and Table 7. It can be converted into lithium carbonate. The experimental data are shown in Table 6 and Table 7. .

[0043] Table 6: Table of the time required for complete conversion of lithium under each pressure condition at a flow rate of 20 m 3 / h of compressed air Table of time required TIFF0007716146000006.tif36135

[0044] Table 7: Table of the time required for complete conversion of lithium under each flow rate condition at a pressure of 0.7 MPa of compressed air Table of time required TIFF0007716146000007.tif36138

[0045] As another embodiment, in the reverse extraction, in the extraction device, the purified and washed P507 organic phase can be reversely extracted with dilute alkali, and the two phases can be separated to obtain blank organic and lithium hydroxide solution. It may also be possible.

[0046] The alkali in the above embodiments may be one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide. It may also be possible.

[0047] The technical effects of Embodiment 1 are as follows. The lithium ion concentration in the raffinate can be reduced to as low as 1 mg / L, and the difficulty of wastewater treatment can be significantly reduced. The recovery rate of lithium can be increased, and the recovery rate of lithium can be made 99% or more. The purity of the lithium salt solution can be increased, and it is ensured that the quality of the lithium carbonate product by precipitation meets the requirements for batteries. The mixing of impurity ions To avoid the introduction of lithium carbonate, further ensure and improve the purity of the product, and ensure that the lithium carbonate product is suitable for battery use. This can ensure that the requirements of

[0048] Embodiment 2: Extraction of battery grade lithium carbonate from P507 raffinate as shown in Figure 1 The method is characterized by including the following steps a to h. a. Impurity adjustment: First, the P507 raffinate is treated with lithium hydroxide or alkali. The pH value is adjusted to 8.5 to 10.5, preferably 9 to 10, or 9.5, and the filtrate is filtered. The resulting solution is then used. Positive ions of impurities such as nickel can be removed by precipitation. b. Extraction: In the extractor, the saponified P507 is mixed with the filtered liquid from the above step. After that, the mixture was left to stand and the phases were separated, leaving the P507 organic phase (organic phase-carrying) and the aqueous phase (raffinate). ) and detect the lithium ion concentration, and if it is less than 1 mg / L, subject it to wastewater treatment. This step allows the lithium in the filtrate to be extracted into the organic phase, and the lithium in the raffinate This reduces the concentration of sodium ions, making wastewater treatment less difficult. c. Purification: In the extraction device, the organic phase (organic phase carrier) in the above step is adjusted to 0.1-0. 25 mol / L, preferably 0.1 to 0.25 mol / L, 0.15 to 0.20 mol / After purifying and washing with 1 L of lithium sulfate solution, the phases were separated by settling, and the P507 organic phase was left. This step removes any sodium or other contaminants from the organic phase. Any impurity ions can be washed away and the lithium ions in the organic phase can be purified. d. Back-extraction: In the extractor, the purified and washed P507 organic phase is extracted with dilute sulfuric acid (or dilute liquid alkali) ), and the two phases are separated and the blank organic and lithium sulfate (or lithium hydroxide) solutions are added. To obtain. This step involves back-extracting lithium in the organic phase to obtain a lithium salt in solution state while increasing the lithium ion concentration and further separating lithium from impurities . e. Alkalization: Heat the lithium solution from the above step to 85 - 95 °C, preferably 90 °C, add lithium hydroxide (or alkali) to adjust the pH value to 9.0 - 13.0, preferably 9.5 - 12.5, 10.0 - 12.0, 10.5 - 11.5, 11, keep warm at 85 - 95 °C, preferably 90 °C, for 2 - 8 hours, preferably 3 - 7 hours, 4 - 6 hours , 5 hours, then let it stand, filter, and use the filtrate. This step can alkalize lithium ions and remove organic impurities and easily precipitated impurities in the lithium solution . f. Crystallization: After alkalization, introduce compressed air into the filtrate at a compressed air pressure of 0.2 - 0.8 MPa , preferably 0.3 - 0.7 MPa, 0.4 - 0.6 MPa, 0.5 MPa, and a compressed air flow rate of 8 - 30 m 3 / h, preferably 10 - 25 m 3 / h, 13 - 22 m 3 / h, 15 - 20 m 3 / h, 16 - 18 m 3 / h while performing evaporation concentration. When fine crystal grains occur in the concentrated solution, discharge the material and cool it. g. Separation: Cool the concentrated solution to room temperature and perform centrifugal separation to obtain lithium carbonate as a solid, and return the liquid to the above step to continue using it in the reaction. h. Base: After centrifugal separation, subject the solid matter to a normal base to obtain lithium carbonate for batteries .

[0049] In Embodiment 2, by adopting the above extraction method, lithium ions in the raffinate The concentration of chlorine can be reduced to 1 mg / L, significantly reducing the difficulty of wastewater treatment. By adopting the alkalinity-air precipitation method, the lithium recovery rate is 99% or more. By adopting extraction separation method, the purity of the lithium salt solution can be improved and the precipitation Ensure that the quality of lithium carbonate products meets the requirements for batteries. By adopting the vapor precipitation method, the contamination of impurity ions is avoided and the purity of the product is further ensured. Maintaining and improving the quality of lithium carbonate products to fully meet the requirements for battery applications and ensure that

[0050] Embodiment 3: As shown in FIGS. 2 to 4, a stirring chamber 5 is provided, and the stirring chamber 5 is connected to a transition tank 6. The P507 raffinate is connected to the clarification chamber 7 and an agitator is provided in the agitation chamber 5. In the extraction apparatus for extracting lithium carbonate for the pond, the stirring chamber 5 is a cube, and the clarification chamber 7 is a rectangular parallelepiped. The aspect ratio of the fining chamber 7 is 4 to 5:1, and the volume ratio of the stirring chamber 5 to the fining chamber 7 is 1:4.5 to 5.5, and the agitator is composed of a main agitator 1 and a sub-agitator 2, and the main agitator 1 The agitator blade 4 is provided in the auxiliary agitator 2, and the agitator blade 4 is configured as a double-layered "cross" shape. The stirring body is configured as a cylindrical stirring body 3, and the cylindrical wall of the cylindrical stirring body 3 has a diameter of 5 to 10 mm. The circular holes are evenly distributed, and the stirring blades 4 are fitted into the cylindrical stirring body 3.

[0051] In another embodiment, the rotation speed of the main agitator 1 is 1000 to 2000 rpm. 100-1300 rpm, 1400-1500 rpm, 1600-1700 rpm The rotation speed of the auxiliary agitator 2 may be 100 to 200 rpm. is revolutions per minute, but may be 110 to 120 revolutions per minute, 130 to 140 revolutions per minute, 150 to 160 revolutions per minute, 170 to 180 revolutions per minute, or 190 revolutions per minute. The operation is as follows The main stirrer performs sufficient mixing, efficiently balances both, and is performed at high speed to achieve a better extraction effect. The sub-stirrer has a low rotational speed and is cylindrical, slows down the fluid movement speed of the mixed liquid due to the high-speed operation of the main stirrer, breaks the phase continuity, and facilitates subsequent phase separation.

[0052] In another embodiment, the maximum diameter of the stirring blades 4 of the main stirrer 1 is 0.2 to 0.33 of the side length of the stirring chamber 5, and the diameter of the cylindrical stirring body 3 of the sub-stirrer is 0.65 to 0.75 of the side length of the stirring chamber 5. The operation is as follows. The stirring paddle has a higher stirring intensity as the paddle is larger. On the other hand, when the stirring paddle exceeds this ratio, the load on the motor increases. While the stirring intensity is too high, emulsification and a large amount of air inhalation occur in both phases, making subsequent phase separation difficult and a large amount of bubbles accumulate in the mixed liquid due to air inhalation, damaging the extraction effect and making phase separation even more difficult.

[0053] In another embodiment, two strip-shaped stabilizing fences 8 are sequentially provided in the clarification chamber 7 The distance from the inlet end of the transition tank 6 of the clarification chamber 7 to the position of the first stabilizing fence is 1 / 4 of the length of the clarification chamber, and the position of the second stabilizing fence in the length of the clarification chamber 7 The distance from the inlet end of the transition tank 6 of the clarification chamber 7 is 1 / 2 of the length of the clarification chamber 7. The operation is as follows. The stabilizing fence is to reduce the flow rate of the mixed liquid and quickly separate both phases If the first stabilizing fence is too close to the inlet of the transition tank, the turbulent flow occurs, causing overflow (the mixed liquid in the tank is blocked in the middle and flows out of the tank in waves) There is a risk of this. If it is too long, there will be no effect, and it will also have an adverse effect on the effect of the second stabilizing fence If the second stabilizing fence is too close to the inlet of the transition tank, when the fluid flows through the first fence and its flow rate decreases, it hits the second fence, and a vortex is formed again between the two fences, adversely affecting the separation of the two phases. If it is too far away, the fluid has already slowed down after passing through the first fence, and the fence loses its expected function

[0054] The extraction principle of the extraction device for extracting lithium carbonate for batteries from P507 raffinate is as follows The organic phase and the lithium-containing aqueous phase are strongly mixed by the high-speed operation of the main agitator, and lithium is transferred from the aqueous phase to the organic phase. After mixing, the two phases are affected by centrifugal force and quickly collide with the sub-agitator, and the mixed phase is dispersed through the holes in it while the sub-agitator is operating, and its flow rate decreases, thus ensuring the extraction effect through destruction and agitation. The mixed liquid enters the clarification chamber through the transfer tank, and the clarification chamber mainly plays the role of separating the two phases. The fence is provided to reduce the flow rate of the fluid and promote phase separation The beneficial effects of the above extraction device for extracting lithium carbonate for batteries from P507 raffinate are as follows. When extracting lithium using an extractant, the capacity of the extractant is affected by the properties of lithium. Therefore, in order to increase the productivity of the extraction tank, a high-speed reaction is required. This extraction tank increases the stirring intensity based on conventional extraction, and also uses a sub-agitator to release emulsification and phase continuity, promote phase separation, and ensure the productivity of the extraction tank .

[0055] Example 1: Extraction method and apparatus for lithium carbonate for batteries from P507 raffinate. The steps are as follows. a. Components of P507 raffinate Li: 1.5 g / L, Fe: 0.0005 g / L, Al: 0.0003 g / L, Zn: 0 .0001 g / L, Ni: 0.035 g / L, Cu: 0.0001 g / L, Pb: 0.0 01 g / L, Ca: 0.0004 g / L, Mg: 0.001 g / L, Na: 3.3 g / L b. For 100 L of raffinate, adjust the pH value to 9.8 using lithium hydroxide and filter. c. Add the filtrate from step b and saponified P507 to the stirring chamber of the started extraction apparatus. After discharging from the extraction apparatus, analyze the raffinate. As a result of detection, Li was 0.00091 g / L (0.91 mg / L). d. Add the organic phase from step c and 0.25 mol / L lithium sulfate solution to the stirring chamber of the started extraction apparatus. After discharging from the extraction apparatus, the aqueous phase flowed into the stirring chamber of step c. e. Add the organic phase from step d and 2.25 mol / L sulfuric acid solution to the stirring chamber of the started extraction apparatus. After discharging from the extraction apparatus, the aqueous phase became a high-concentration lithium solution and the organic phase became a blank organic. 7950 mL of lithium solution with a concentration of 20.3 g / L was obtained. After subtracting the lithium hydroxide used for pH adjustment, the extraction yield was 99.47%. f. Heat the lithium solution to 92 °C, adjust the pH value to 12.5 using lithium hydroxide, keep it warm at 90 °C, let it stand, react for 2 hours, and then filter. g. Add the filtrate from step f to the reactor. After the addition is complete, introduce compressed air at 0.65 MP a and a flow rate of 16.3 m / h, heat up and evaporate to generate fine crystals in the reactor. 3 Then, the introduction of compressed air and the temperature increase were stopped, and the lithium solution in the reactor was discharged and cooled. . h. Cool the lithium solution to room temperature, then separate and base the solution, and return the mother liquor to step g. Therefore, the overall yield of lithium was 99.47%. i. After lithium carbonate was used as a base, the results were as follows: Li2CO3:99.61%, Fe:0.0001%, Al:0.0002%, Zn:0 .0001%, Ni: 0.0007%, Cu: 0.0001%, Pb: 0.0001%, Ca:0.0004%, Mg:0.0011%, Na:0.0023%, K:0.000 3%, Si:0.0012%, SO4 2- :0.017%, Cl - :0.001%

[0056] Example 2: Method and apparatus for extracting lithium carbonate for batteries from P507 raffinate The steps are as follows: a.P507 Raffinate Component Li:2.35g / L, Fe:0.0002g / L, Al:0.0009g / L, Zn: 0.0003g / L, Ni: 0.017g / L, Cu: 0.0001g / L, Pb: 0. 001g / L, Ca:0.0005g / L, Mg:0.0012g / L, Na:2.12 g / L b. Adjust the pH of 100L of raffinate to 10.2 using lithium hydroxide. and filtered. c. Add the filtrate from step b and the saponified P507 to the stirring chamber of the activated extractor and extract. After being discharged from the extraction device, the raffinate was analyzed and found to contain 0.00077g of Li. / L (0.77 mg / L). d. Add the organic phase from step c and 0.18 mol / L of lithium sulfate to the stirring chamber of the activated extractor. After adding the thium solution and discharging it from the extraction device, the aqueous phase flowed into the stirring chamber of step c. e. Add the organic phase of step d and the 2.13 mol / L sulfuric acid solution to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase becomes a high-concentration lithium solution and the organic phase becomes a blank organic. As a result, 12050 mL of a lithium solution with a concentration of 19.43 g / L was obtained. After subtracting the lithium hydroxide used for pH adjustment, the extraction yield was 99.63%. f. Heat the lithium solution to 95 °C, adjust the pH value to 12.5 using lithium hydroxide, keep it warm at 95 °C, let it stand, react for 2 hours, and then filter. g. Add the filtrate of step f into the reactor. After the addition is completed, introduce compressed air at a pressure of 0.70 MPa and a flow rate of 18.2 m / h, heat up and evaporate. When fine crystals are generated in the reactor, stop the introduction of compressed air and heating, and discharge and cool the lithium solution in the reactor. h. Cool the lithium solution to room temperature, then perform separation and basification, and return the mother liquor to step g for use in the reaction. Therefore, the overall yield of lithium was 99.63%. i. Analyze based on lithium carbonate, and the detection results are shown below. Li2CO3: 99.58%, Fe: 0.0006%, Al: 0.0007%, Zn: 0.0005%, Ni: 0.0002%, Cu: 0.0005%, Pb: 0.0005%, Ca: 0.0006%, Mg: 0.0009%, Na: 0.0011%, K: 0.0003%, Si: 0.0017%, SO4: 0.041%, Cl: 0.001% Example 3: In the method and device for extracting lithium carbonate for batteries from P507 raffinate, 3 / h, heat up and evaporate. When fine crystals are generated in the reactor, stop the introduction of compressed air and heating, and discharge and cool the lithium solution in the reactor. h. Cool the lithium solution to room temperature, then perform separation and basification, and return the mother liquor to step g for use in the reaction. Therefore, the overall yield of lithium was 99.63%. h. After cooling the lithium solution to room temperature, perform separation and basification, and return the mother liquor to step g for use in the reaction. As a result, the overall lithium yield was 99.63%. i. Analyze based on lithium carbonate, and the detection results are as follows. Li2CO3: 99.58%, Fe: 0.0006%, Al: 0.0007%, Zn: 0.0005%, Ni: 0.0002%, Cu: 0.0005%, Pb: 0.0005%, Ca: 0.0006%, Mg: 0.0009%, Na: 0.0011%, K: 0.0003%, Si: 0.0017%, SO4: 0.041%, Cl: 0.001% 2- -

[0057] Example 3: In the method and apparatus for extracting lithium carbonate for batteries from P507 raffinate, The steps are as follows. a. Components of the P507 raffinate Li: 0.93 g / L, Fe: 0.0005 g / L, Al: 0.0005 g / L, Zn: 0.0001 g / L, Ni: 0.055 g / L, Cu: 0.0005 g / L, Pb: 0. 003 g / L, Ca: 0.0005 g / L, Mg: 0.0007 g / L, Na: 1.37 g / L b. For 100 L of the raffinate, the pH value was adjusted to 9.5 using lithium hydroxide and then filtered. c. The filtrate from step b and saponified P507 were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the raffinate was analyzed and detected. As a result, Li was 0.00083 g / L (0.83 mg / L). d. The organic phase from step c and 0.22 mol / L lithium sulfate solution were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase flowed back to the stirring chamber of step c. e. The organic phase from step d and 2.01 mol / L sulfuric acid solution were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase became a high-concentration lithium solution, and the organic phase became a blank organic. 4860 mL of lithium solution with a concentration of 19.11 g / L was obtained. After subtracting the lithium hydroxide used for pH adjustment, the extraction yield was 99.86%. f. The temperature of the lithium solution was raised to 90 °C, and the pH value was adjusted to 12.2 using lithium hydroxide and then kept warm at 90 °C and allowed to stand. After reacting for 2 hours, it was filtered. g. The filtrate from step f was added to the reactor. After the addition was completed, compressed air was introduced at 0.55 MP a and a flow rate of 21.2 m 3 / h. The temperature was raised and evaporated. When fine crystals were generated in the reactor the introduction of compressed air and the temperature increase were stopped, and the lithium solution in the reactor was discharged and cooled. . h. After cooling the lithium solution to room temperature, separation and basification were carried out, and the mother liquor was returned to step g and used for the reaction. Therefore, the overall yield of lithium was 99.86%. i. After basifying lithium carbonate, analysis was performed, and the detection results are shown below. Li2CO3: 99.59%, Fe: 0.0007%, Al: 0.0005%, Zn: 0 .0003%, Ni: 0.0005%, Cu: 0.0001%, Pb: 0.0006%, Ca: 0.0005%, Mg: 0.0005%, Na: 0.0013%, K: 0.000 5%, Si: 0.0032%, SO4 2- : 0.033%, Cl - : 0.001%.

[0058] Example 4: In the method and apparatus for extracting lithium carbonate for batteries from P507 raffinate, the steps are as follows. a. Components of P507 raffinate Li: 5.5 g / L, Fe: 0.001 g / L, Al: 0.0011 g / L, Zn: 0. 0021 g / L, Ni: 0.075 g / L, Cu: 0.0023 g / L, Pb: 0.00 1 g / L, Ca: 0.0016 g / L, Mg: 0.001 g / L, Na: 5.3 g / L b. For 100 L of raffinate, the pH value was adjusted to 10.5 using lithium hydroxide and filtered. c. The filtrate from step b and saponified P507 were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the raffinate was analyzed and detected. As a result, Li was 0.00033 g / L (0.33 mg / L). d. The organic phase from step c and 0.19 mol / L lithium sulfate solution were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase flowed into the stirring chamber of step c. d. The organic phase from step c and 0.19 mol / L lithium sulfate solution were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase flowed into the stirring chamber of step c. d. The organic phase from step c and 0.19 mol / L lithium sulfate solution were added to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase flowed into the stirring chamber of step c. e. Add the organic phase from step d and the 2.15 mol / L sulfuric acid solution to the stirring chamber of the started extraction device. After discharging from the extraction device, the aqueous phase becomes a high-concentration lithium solution and the organic phase becomes blank organic. As a result, 27350 mL of a lithium solution with a concentration of 20.17 g / L was obtained. After subtracting the lithium hydroxide used for pH adjustment, the extraction yield was 99.66%. f. Heat the lithium solution to 95 °C and adjust the pH value to 11.9 using lithium hydroxide. Keep it warm at 90 °C, let it stand, react for 2 hours, and then filter. g. Add the filtrate from step f into the reactor. After the addition is completed, introduce compressed air at 0.75 MPa and a flow rate of 18.3 m / h, heat up and evaporate. When fine crystals appear in the reactor, stop introducing compressed air and heating up, and discharge and cool the lithium solution in the reactor. 3 h. After cooling the lithium solution to room temperature, separate and basify it, and return the mother liquor to step g for use in the reaction. Therefore, the overall yield of lithium was 99.66%. i. Analyze based on lithium carbonate, and the detection results are shown below. Li2CO3: 99.53%, Fe: 0.0005%, Al: 0.0007%, Zn: 0 .0005%, Ni: 0.0005%, Cu: 0.0005%, Pb: 0.0003%, Ca: 0.0009%, Mg: 0.0017%, Na: 0.0037%, K: 0.000 1%, Si: 0.0019%, SO4 2- : 0.023%, Cl - : 0.001%

[0059] Example 5: As shown in Figures 2 to 4, in the extraction device for extracting lithium carbonate for batteries from P507 raffinate, a stirring chamber 5 is provided. The stirring chamber 5 is connected to a clarification chamber 7 via a transition tank 6. ​​​​​​​​ Continuously, a stirrer is provided in the stirring chamber 5. The stirring chamber 5 is cubic, and the clarification chamber 7 is rectangular parallelepiped. The aspect ratio of the clarification chamber 5 is 4 - 5:1, and the volume ratio of the stirring chamber 5 to the clarification chamber 7 is 1 :4.5 - 5.5. The stirrer consists of a main stirrer 1 and a sub - stirrer 2. The main stirrer 1 is provided with stirring blades 4. The stirring blades 4 are configured in a two - layer "cross" shape. The stirring body of the sub - stirrer 2 is configured as a cylindrical stirring body 3. On the cylindrical wall of the cylindrical stirring body 3, circular holes with a diameter of 5 - 10 mm are evenly distributed, and the stirring blades 4 are fitted into the cylindrical stirring body 3.

[0060] Example 6: As shown in Figs. 2 - 4, in the extraction device for extracting lithium carbonate for batteries from P507 raffinate, a stirring chamber 5 is provided. The stirring chamber 5 is connected to the clarification chamber 7 via a transition tank 6 Continuously, a stirrer is provided in the stirring chamber 5. The stirring chamber 5 is cubic, and the clarification chamber 7 is rectangular parallelepiped. The aspect ratio of the clarification chamber 7 is 4 - 5:1, and the volume ratio of the stirring chamber 5 to the clarification chamber 7 is 1 :4.5 - 5.5. The stirrer consists of a main stirrer 1 and a sub - stirrer 2. The main stirrer 1 consists of a main stirrer drive motor 12 and stirring blades 4. The stirring blades 4 are in a two - layer "cross" shape. The sub - stirrer 2 consists of a sub - stirrer drive motor 11, a drive wheel 10 that is drivably connected to the drive motor 11, a sub - stirrer transmission wheel 9 that is drivably connected to the drive wheel 10, and a cylindrical stirring body 3 that is connected to the transmission wheel 9. A central hole is provided in the sub - stirrer transmission wheel 9, and the shaft of the stirring blades 4 of the main stirrer 1 passes through the central hole of the transmission wheel 9. A support bearing is supported under the transmission wheel 9. The drive wheel 10 and the transmission wheel 9 adopt gear connection or friction connection. The main stirrer drive motor 12 and the sub - stirrer drive motor 11 are fixed to the top cover of the stirring chamber 5 via brackets. . The rotation speed of the main stirrer 1 is 1000 - 2000 revolutions per minute, and the rotation speed of the sub - stirrer 2 is 10 0 - 200 revolutions per minute. The maximum diameter of the stirring blades 4 of the main stirrer 1 is 0 .28 - 0.33 of the side length of the stirring chamber 5, and the diameter of the cylindrical stirring body 3 of the sub - stirrer 2 is 0. 65 - 0.75 of the side length of the stirring chamber 5. Circular holes with a diameter of 5 - 10 mm are evenly distributed on the cylindrical wall of the cylindrical stirring body 3. One circular hole is provided per square centimeter. The stirring blades 4 are fitted into the cylindrical stirring body 3. In the clarification chamber, two strip - shaped stabilizing fences 8 are arranged in a zigzag pattern . The distance from the inlet end of the transition tank 6 of the clarification chamber 7 to the position of the first stabilizing fence on the left side is 1 / 4 of the length of the clarification chamber 7, and the distance from the inlet end of the transition tank 6 of the clarification chamber 7 to the position of the second stabilizing fence on the right side in the length direction of the clarification chamber 7 is , 1 / 2 of the length of the clarification chamber 7. The stabilizing fence 8 is an ordinary fence.

[0061] The above are only preferred embodiments of the present invention and do not limit the present invention. Those skilled in the art will be able to make various changes and modifications to the present invention. Any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and principles of the present invention are included in the patent scope of the present invention.

Industrial Applicability

[0062] The present invention has been started for industrial production and application. The lithium recovery rate is over 99%, and the produced lithium carbonate product meets the standards of lithium carbonate for batteries.​

Claims

1. A method for extracting lithium carbonate for batteries from P507 raffinate, including the steps of impurity adjustment, extraction, purification, back-extraction, alkalization, crystallization, separation, and baking, wherein in the impurity adjustment, first, the pH value of the P507 raffinate is adjusted to 8.5 - 10.5 using lithium hydroxide or an alkali, filtered, and the filtrate is used, in the extraction, saponified P507 is mixed with the liquid after impurity adjustment and filtration, then left standing to separate the phases, leaving the P507 organic phase, and for the aqueous phase, the lithium ion concentration is detected , and if it is less than 1 mg / L, it is subjected to wastewater treatment, in the purification, the extracted organic phase is purified and washed with a 0.1 - 0.25 mol / L lithium sulfate solution, then left standing to separate the phases, leaving the P507 organic phase, and the aqueous phase is used for extraction, in the back-extraction, the P507 organic phase after purification and washing is back-extracted with dilute sulfuric acid, and the two phases are separated to obtain blank organic and a lithium sulfate solution, in the alkalization, the lithium solution is heated to 85 - 95 °C, lithium hydroxide or an alkali is added to adjust the pH value to 9.0 - 13.0, and it is kept warm at 85 - 95 °C for 2 - 8 hours, then left standing, filtered, and the filtrate is used, in the crystallization, after alkalization, while introducing compressed air into the filtrate at a compressed air pressure of 0.2 - 0.8 MPa and a compressed air flow rate of 8 - 30 m3 / h, evaporation concentration is carried out, and when fine crystals appear in the concentrated solution, the material is discharged and cooled, which is characterized by the extraction method.

2. In the impurity adjustment, first, the pH value of the P507 raffinate is adjusted to 9 - 10 using lithium hydroxide or an alkali, filtered, and the filtrate is used, which is characterized by the method for extracting lithium carbonate for batteries from P507 raffinate according to Claim 1.

3. In the purification step, after extraction, the organic phase is purified and washed with a 0.15 - 0.20 mol / L lithium sulfate solution, which is characterized by the method for extracting lithium carbonate for batteries from P507 raffinate according to Claim 1 .

4. In the back-extraction, the P507 organic phase after purification and washing is back-extracted with dilute liquid alkali, and the two phases are separated to obtain blank organic and a lithium hydroxide solution, which is characterized by the method for extracting lithium carbonate for batteries from P507 raffinate according to Claim 1 .

5. In the alkalization, the lithium solution is heated to 90°C, lithium hydroxide or an alkali is added to adjust the pH value to 10.0 to 12.0, and the mixture is kept warm at 90°C and allowed to stand for 4 to 6 hours. Thereafter, filtration is carried out, and the filtrate is used. The method for extracting lithium carbonate for batteries from P507 raffinate according to claim 1 is characterized by this.

6. In the crystallization step, the compressed air pressure is 0.4 to 0.6 MPa, and the compressed air flow rate is 10 to 20 m3 / h. The method for extracting lithium carbonate for batteries from P507 raffinate according to claim 1 is characterized by this.

Images