Combined acid-base reaction device for lithium precipitation mother liquor in lithium carbonate preparation process

Abstract

The utility model relates to a combined acid-base reaction device for lithium precipitation mother liquor in a lithium carbonate preparation process, which comprises two reaction tubes which are sequentially communicated along the vertical direction, a rotational flow internal part for scattering mixed liquor is arranged in each reaction tube, and the side surface of each reaction tube is communicated with a liquid inlet tube positioned above the rotational flow internal part; and a PH meter which is positioned below the rotational flow inner piece and is used for measuring the mixed liquid is also arranged in the reaction tube. According to the utility model, through the arrangement of the two reaction tubes which are connected in sequence and the rotational flow inner piece, mixed liquid is fully and quickly mixed and reacted in the reaction tubes in the flowing process, so that the lithium precipitation mother liquid is subjected to acid adding reaction and acid-base neutralization reaction in the flowing process, carbonate and lithium carbonate solid particles in the mother liquid are eliminated, and the lithium precipitation mother liquid is obtained. Meanwhile, the PH value of the mother liquor is conveniently and quickly adjusted, and the efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the field of equipment, in particular to the technical field of chemical process equipment components, and specifically refers to a combined acid-base reaction device for lithium precipitation mother liquor in the process of lithium carbonate preparation. Background Art

[0002] During the preparation of battery-grade lithium carbonate, the mother liquor from the lithium carbonate workshop needs to be neutralized with sulfuric acid to remove carbonate ions. The equipment used to achieve this is a neutralization kettle. The neutralization kettle is equipped with feeding valves for the mother liquor and sulfuric acid, as well as metering and detection devices. During normal production, the mother liquor feeding valve on the neutralization kettle is opened to add the mother liquor. The sulfuric acid feeding valve is then opened to allow the mother liquor and sulfuric acid to undergo an acid-base neutralization reaction. However, because traditional methods cannot adjust the pH value of the reaction mixture, and the reaction takes place within the neutralization kettle, the operation is cumbersome and inefficient. Furthermore, since the mother liquor needs to further adjust its pH value, liquid caustic soda is also required, which increases the workload of operators, reduces production efficiency, and easily causes fluctuations in the final process indicators, posing a corrosion risk to the evaporation equipment in the subsequent process. Utility Model Content

[0003] In response to the deficiencies of the prior art, the utility model provides a combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process. Through two sequentially connected reaction tubes and the arrangement of cyclone internals, the mixed liquor is fully and rapidly mixed and reacted in the reaction tubes and during the descending process, so that the lithium precipitation mother liquor completes the acid addition reaction and the neutralization reaction during the downward flow process, thereby eliminating carbonate ions and lithium carbonate solid particles, and at the same time facilitates the rapid adjustment of the final pH value of the mother liquor.

[0004] The utility model is realized by the following technical scheme: a combined acid-base reaction device for lithium precipitation mother liquor in the process of preparing lithium carbonate, comprising two reaction tubes connected in sequence along the vertical direction, a cyclone inner part for breaking up the mixed liquid is provided in the reaction tube, a liquid inlet pipe located above the cyclone inner part is connected to the side of the reaction tube, and a pH meter located below the cyclone inner part for measuring the mixed liquid is also provided in the reaction tube.

[0005] When the preferred solution is in use, the lithium ion mother liquor is supplied at a constant flow rate by a centrifugal pump, and the lithium ion mother liquor enters the upper reaction tube from the liquid inlet of the reaction tube located above, and enters the upper reaction tube with the sulfuric acid from the sulfuric acid high-level tank through the liquid inlet pipe, and the lithium ion mother liquor and the sulfuric acid contact and react in the reaction tube, and the mixed solution of the lithium ion mother liquor and the sulfuric acid is fully dispersed and mixed after passing through the cyclone internals, thereby eliminating carbonate ions and lithium carbonate solid particles, and the mother liquor reacts with sulfuric acid to form a reaction solution, and the reaction solution is measured when it flows through the pH meter. Since the flow rate of the lithium ion mother liquor is basically constant, the number of carbonate ions and lithium carbonate solid particles in the mother liquor varies. When the process requires that the pH value of the reaction solution end point reaches a specified pH index, the carbonate ions and lithium carbonate solid particles in the lithium ion mother liquor can be completely eliminated, so the amount of sulfuric acid added during the reaction varies, and therefore the pH value measured by the pH meter is used to adjust the amount of sulfuric acid entering to ensure that the pH value of the reaction solution meets the index range required by the process, thereby effectively improving the efficiency of the reaction of the lithium ion mother liquor with sulfuric acid;

[0006] Next, the pH value of the reaction liquid needs to be further adjusted to meet the process requirements of the subsequent stage. The reaction liquid and liquid alkali enter the reaction tube located below and are fully mixed and reacted by the cyclone internals to form a neutralized liquid. The pH value of the mother liquor is adjusted. The process requires that the pH value of the neutralized liquid must meet the specified pH index. Therefore, the pH value of the neutralized liquid is measured by a pH meter, and then the amount of liquid alkali entering is adjusted to ensure that the pH value of the neutralized liquid is within the index range required by the process.

[0007] By means of two sequentially connected reaction tubes and the arrangement of cyclone internals, the mixed liquid is fully and rapidly mixed and reacted in the reaction tube and during the circulation process, so that the lithium precipitation mother liquor completes the acid addition reaction and the neutralization reaction during the flow process, thereby eliminating carbonate ions and lithium carbonate solid particles. At the same time, it is also convenient to quickly adjust the pH value of the mother liquor and improve production efficiency.

[0008] Preferably, an intermediate tube is provided between the two reaction tubes, the liquid inlet of the intermediate tube is connected to the liquid outlet of the upper reaction tube, and the liquid outlet of the intermediate tube is connected to the liquid inlet of the lower reaction tube.

[0009] In this preferred solution, the intermediate tube is provided to connect the two reaction tubes, thereby facilitating the connection of the two reaction tubes.

[0010] Preferably, the cyclone internals include a plurality of spiral blades arranged vertically and connected in sequence, and the diameter of the blades is adapted to the inner diameter of the reaction tube.

[0011] When this preferred solution is in use, the three spiral blades are arranged to achieve full dispersion and mixing of the mixed liquid, thereby facilitating a full reaction.

[0012] Preferably, a first flange is fixed to the bottom end of the lowest blade, and the first flange is connected to the inside of the reaction tube.

[0013] In this preferred solution, the first flange is provided to facilitate the fixation of the blades in the reaction tube.

[0014] Preferably, plug-in slots are provided on both end faces of the blades, and two adjacent blades are plug-connected through the corresponding two plug-in slots.

[0015] In this preferred solution, the grooves are provided to play a positioning role, thereby facilitating the sequential connection of a plurality of blades.

[0016] Preferably, between two adjacent blades, the bottom surface of the upper blade forms a certain angle with the bottom surface of the lower blade.

[0017] When the preferred solution is in use, the plurality of blades form an angle, which further promotes the dispersion and mixing of the mixed liquid, thereby facilitating a full reaction.

[0018] Preferably, the reaction tube includes a top pipe section, a middle pipe section, and a lower pipe section connected in sequence by flanges, the top pipe section is connected to the liquid inlet, the middle pipe section is provided with the blade, the detection end of the pH meter is inserted into the lower pipe section, and the two second flanges connecting the middle pipe section and the lower pipe section are connected to the first flange.

[0019] This preferred solution facilitates the replacement of various components through the arrangement of the reaction tube, and also facilitates the installation of the cyclone internals in the middle tube section.

[0020] As an advantage, the liquid inlet pipe is further provided with a regulating valve. This preferred solution facilitates adjusting the inlet amount of the acid or alkali solution through the provision of the regulating valve.

[0021] The beneficial effects of the utility model are as follows: the lithium precipitation mother liquor is supplied at a constant flow rate by a centrifugal pump, the lithium precipitation mother liquor enters the upper reaction tube from the liquid inlet of the reaction tube located above, and enters the upper reaction tube with the sulfuric acid from the sulfuric acid high-level tank through the liquid inlet pipe, the lithium precipitation mother liquor and the sulfuric acid contact and react in the reaction tube, the mixed liquor of the lithium precipitation mother liquor and the sulfuric acid is fully dispersed and mixed after passing through the cyclone internal component, thereby eliminating carbonate ions and lithium carbonate solid particles, the mother liquor reacts with the sulfuric acid to become a reaction liquid, the pH value of the reaction liquid is measured when it flows through the pH meter, since the flow rate of the lithium precipitation mother liquor is basically constant, due to the change in the number of carbonate ions and lithium carbonate solid particles in the mother liquor, the process requires that the end pH value of the reaction liquid reaches the specified pH index, the carbonate ions and lithium carbonate solid particles in the lithium precipitation mother liquor can be completely eliminated, then the amount of sulfuric acid added changes during the reaction process, therefore the pH value measured by the pH meter is used to adjust the amount of sulfuric acid entering, to ensure that the pH value of the reaction liquid reaches within the index range required by the process, and effectively improve the efficiency of the reaction between the lithium precipitation mother liquor and sulfuric acid;

[0022] Next, the pH value of the reaction liquid needs to be further adjusted to meet the process requirements of the subsequent stage. The reaction liquid and liquid alkali enter the reaction tube located below, and after sufficient mixing and reaction in the cyclone internals, a neutralized liquid is formed. The pH value of the mother liquor is adjusted. The process requires that the pH value of the neutralized liquid must meet the specified pH index. Therefore, the pH value is measured by the pH meter, and then the amount of alkali solution entering is adjusted to ensure that the pH value of the neutralized liquid is within the index range required by the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of the utility model;

[0024] Figure 2 It is a three-dimensional schematic diagram of the swirl internals;

[0025] As shown in the figure:

[0026] 1. Reaction tube, 2. Intermediate tube, 3. Cyclone internals, 4. Regulating valve, 5. Lithium precipitation mother liquor inlet, 6. Sulfuric acid, 7. Liquid alkali, 8. Reaction liquid, 9. Neutralizing liquid, 10. pH meter, 11. Top pipe section, 12. Middle pipe section, 13. Lower pipe section. DETAILED DESCRIPTION

[0027] In order to clearly illustrate the technical features of this solution, this solution is described below through specific implementation methods.

[0028] Refer to the attached Figure 1-2 The utility model discloses a combined acid-base reaction device for lithium precipitation mother liquor in the process of lithium carbonate preparation, comprising two reaction tubes 1 arranged vertically and with their axes extending vertically, an intermediate tube 2 is provided between the two reaction tubes 1, the liquid inlet of the intermediate tube 2 is connected to the liquid outlet of the upper reaction tube 1, and the liquid outlet of the intermediate tube 2 is connected to the liquid inlet of the lower reaction tube 1. In order to resist corrosion from strong acids and strong alkalis, the pipe fittings in this scheme are all steel-lined with polytetrafluoroethylene.

[0029] The reaction tube 1 comprises a top pipe section 11, a middle pipe section 12, and a lower pipe section 13 which are connected in sequence through flanges. A liquid inlet pipe is connected to the side of the top pipe section 11, and a regulating valve 4 is provided on the liquid inlet pipe.

[0030] A swirl internal 3 is provided in the middle pipe section 12. The swirl internal 3 includes three spiral blades arranged vertically and connected in sequence. The diameter of the blades is adapted to the inner diameter of the reaction tube 1. The bottom end of the lowest blade is fixedly connected to a first flange. The two second flanges connecting the middle pipe section 12 and the lower pipe section 13 are connected to the first flange.

[0031] In two adjacent blades, the bottom surface of the upper blade forms a certain angle with the lower blade, and plug-in grooves are provided on both end surfaces of the blades. When the two adjacent blades are connected, the corresponding two plug-in grooves are inserted into each other so that the bottoms of the two plug-in grooves are connected. The width of the plug-in groove is adapted to the thickness of the blade, and the two adjacent blades are plug-in connected through the corresponding two plug-in grooves. The blades are made of polytetrafluoroethylene material.

[0032] A pH meter 10 is provided on the side of the lower pipe section 13 and is located outside the reaction tube 1. The detection end of the pH meter 10 is inserted into the lower pipe section 13 to measure the pH value of the mixed liquid flowing through the lower pipe section 13. The actuator signal of the regulating valve 4 is connected to the controller, and the controller and the pH meter 10 are electrically connected to the control console.

[0033] When the utility model is in use, the lithium precipitation mother liquor is supplied at a constant flow rate through a centrifugal pump, the lithium precipitation mother liquor enters the upper reaction tube 1 from the liquid inlet of the upper reaction tube 1, and enters the upper reaction tube 1 with sulfuric acid 6 from the sulfuric acid high-level tank through the liquid inlet pipe. The lithium precipitation mother liquor and the sulfuric acid contact and react in the reaction tube 1. After passing through the cyclone internal part 3, the mixed liquid of the lithium precipitation mother liquor and the sulfuric acid is fully dispersed and mixed, thereby eliminating carbonate radicals and lithium carbonate solid particles. After the mother liquor reacts with the sulfuric acid, it becomes a reaction liquid 8. When the reaction liquid 8 flows through the pH meter 10, the pH value is measured.

[0034] Since the flow rate of the lithium precipitate mother liquor is basically constant, the number of carbonate ions and lithium carbonate solid particles in the mother liquor varies. The process requires that the carbonate ions and lithium carbonate solid particles in the lithium precipitate mother liquor can be completely eliminated only when the endpoint pH value of the reaction solution 8 reaches the specified pH index. Then, the amount of sulfuric acid added varies during the reaction process. Therefore, the pH value measured by the pH meter 10 is used to adjust the amount of sulfuric acid entering to ensure that the pH value of the reaction solution 8 reaches within the index range required by the process. By comparing the pH value of the reaction solution 8 with the specified pH index, when the detected value is lower than the specified value, the controller sends a signal to the regulating valve 4 to adjust the opening of the regulating valve 4 to appropriately reduce the sulfuric acid flow rate. Conversely, when the detected value is higher than the specified value, the controller sends a signal to the regulating valve 4 to adjust the opening of the regulating valve 4 to appropriately increase the sulfuric acid flow rate to ensure that the pH value of the reaction solution 8 reaches within the index range required by the process, thereby effectively improving the efficiency of the reaction between the lithium precipitate mother liquor and sulfuric acid.

[0035] Next, the pH value of the reaction liquid 8 needs to be further adjusted to meet the process requirements of the subsequent stage. The reaction liquid 8 enters the reaction tube 1 through the intermediate tube 2. The reaction liquid 8 is supplied in a quantitative manner and mixed with the liquid alkali 7 from the liquid alkali high-level tank in the reaction tube below through the regulating valve. After sufficient mixing reaction through the swirl internal part 3, a neutralizing liquid 9 is formed. The process requires that the pH value of the neutralizing liquid 9 be adjusted back to the specified index to meet the requirements of the evaporation process. The controller sets a basic opening of the regulating valve, and the online pH meter detects the pH value of the neutralizing liquid in real time. The detected pH value of the neutralizing liquid is compared with the specified pH index. When the detected value is lower than the specified value, the controller sends a signal to the regulating valve to adjust the opening of the regulating valve to appropriately increase the liquid alkali flow rate. Conversely, when the detected value is higher than the specified value, the controller sends a signal to the regulating valve to adjust the opening of the regulating valve to appropriately reduce the liquid alkali flow rate to ensure that the pH value of the neutralizing liquid 9 meets the index range required by the process.

[0036] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved through or by adopting existing technologies, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not depart from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process, characterized in that: The invention comprises two reaction tubes (1) connected in sequence along the vertical direction, wherein a cyclone inner part (3) for breaking up a mixed liquid is provided in the reaction tube (1), a liquid inlet pipe located above the cyclone inner part (3) is connected to the side of the reaction tube (1), and a pH meter (10) for measuring the mixed liquid is further provided on the side of the reaction tube (1) and located below the cyclone inner part (3).

2. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 1, characterized in that: An intermediate tube (2) is further provided between the two reaction tubes (1); the liquid inlet of the intermediate tube (2) is connected to the liquid outlet of the upper reaction tube (1), and the liquid outlet of the intermediate tube (2) is connected to the liquid inlet of the lower reaction tube (1).

3. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 1, characterized in that: The cyclone internal component (3) comprises a plurality of spiral blades arranged vertically and connected in sequence, wherein the diameter of the blades is adapted to the inner diameter of the reaction tube (1).

4. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 3, characterized in that: The bottom end of the lowest blade is fixedly connected to a first flange, and the first flange is connected to the reaction tube (1).

5. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 3, characterized in that: Plug-in slots are provided on both end surfaces of the blades, and two adjacent blades are plug-connected through the corresponding two plug-in slots.

6. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 3, characterized in that: In two adjacent blades, the bottom surface of the upper blade forms a certain angle with the bottom surface of the lower blade.

7. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 4, characterized in that: The reaction tube (1) comprises a top tube section (11), a middle tube section (12), and a lower tube section (13) connected in sequence by flanges, the top tube section being connected to a liquid inlet, the middle tube section (12) being provided with the blade, the detection end of the pH meter (10) being inserted into the lower tube section (13), and the two second flanges connecting the middle tube section (12) and the lower tube section (13) being connected to the first flange.

8. The combined acid-base reaction device for lithium precipitation mother liquor in the lithium carbonate preparation process according to claim 1, characterized in that: The liquid inlet pipe is also provided with a regulating valve (4).

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