Equipment for removing impurities from brine and application method thereof

Abstract

The invention relates to the technical field of purification and impurity removal, in particular to brine impurity removal equipment and an application method thereof. The invention provides equipment for removing impurities from brine and an application method of the equipment, the equipment comprises a stepped continuous purification tank, a deep cone thickening tank and an inclined tube settling tank, is used for removing impurities such as magnesium, ferromanganese and aluminum in the brine, and is high in productivity, high in automation degree, low in labor intensity and high in efficiency. The invention further provides an application method of the equipment, the pH value of the brine is adjusted through the liquid caustic soda, then the flocculating agent is added to remove impurities in the brine, the content of magnesium and ferromanganese in the purified brine is reduced to 0.0001 g / L, the content of aluminum is reduced to 0.001 g / L, meanwhile, after the impurities are removed through the equipment, the slag rate is greatly reduced to 0.2%, and the quality of the brine is improved. The technical problems that in the prior art, the impurity slag removal amount is large, and the cost of recycling the lithium in the slag is high are solved, and the purposes that the impurity slag removal amount is small, the cost of recycling the lithium in the slag is reduced, and circular economy is well achieved are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of purification and impurity removal, and in particular to equipment for removing impurities from brine and an application method thereof. Background Art

[0002] Lepidolite is also called "lepidolite", the main component of which is KLi 1.5 Al 1.5 [AlSi 3 O 10 ](F,OH) 2 , containing Li 2 O is about 1.23-5.90%, and also contains other rare metals such as rubidium and cesium; Yichun City has the world's largest lithium mica mine, and the exploitable amount of lithium oxide accounts for 31% of the country and 8.2% of the world. Lepidolite is the most common lithium mineral and an important mineral for refining lithium. Its comprehensive development and utilization has very important economic and strategic value.

[0003] Lithium carbonate is an important chemical raw material. With the national new energy development plan, lithium-ion new energy has become one of the country's key energy industries to support development. As an important basic raw material for the development of lithium-ion new energy, lithium carbonate is increasingly important in new energy materials.

[0004] However, there are a lot of impurities in lithium mica ore. In the process of smelting and extracting lithium, multiple impurity removal processes are required to obtain a product with purity that meets the requirements. The conventional impurity removal method is to add the configured lime milk, add it to a 20-cubic-meter reactor, remove impurities in the reactor, and use a filter press to achieve liquid-solid separation. However, this method has a large amount of slag (slag rate of 2%), high labor intensity and low efficiency. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an equipment for removing impurities from brine and an application method thereof in view of the deficiencies of the above-mentioned prior art, including a stepped continuous purification tank, a deep cone thickening tank and an inclined tube sedimentation tank, which are used to remove impurities such as magnesium, ferromanganese and aluminum in the brine. The pH value of the brine is adjusted by liquid alkali, and then a flocculant is added to remove impurities in the brine. After purification, the contents of magnesium and ferromanganese in the brine are reduced to 0.0001g / L, and the content of aluminum is reduced to 0.001g / L. At the same time, the slag removal rate is greatly reduced to 2‰ by liquid alkali. The application method solves the technical problems of large amount of slag removal and high cost of lithium recovery in the slag in the prior art, thereby achieving the goal of small amount of slag removal, reduced cost of lithium recovery in the slag and well realizing the purpose of circular economy.

[0006] In order to solve the above technical problems, the present invention provides a brine impurity removal device, comprising:

[0007] Reaction tank;

[0008] A purified liquid transfer tank, the input end of which is connected to the output end of the reaction tank through a first chute;

[0009] A deep cone thickening tank, the input end of which is connected to the output end of the purified liquid transfer tank through a first connecting elbow;

[0010] An inclined tube settling tank, the input end of which is connected to the upper output end of the deep cone thickening tank through a second chute;

[0011] The input end of the inclined tube transfer trough is connected with the upper output end of the inclined tube sedimentation trough through a third chute.

[0012] According to the equipment for removing impurities from brine provided by the present invention, the reaction tank is provided with one or a plurality of reaction tanks are provided in series, and a pH detector is provided at the output port of the reaction tank.

[0013] According to the equipment for removing impurities from brine provided by the present invention, a liquid inlet is further provided at the input end of the deep cone thickening tank, and the liquid inlet is connected to an auxiliary agent storage box.

[0014] According to the equipment for removing impurities from brine provided by the present invention, the bottom of the inclined tube settling tank is connected to the input end of the deep cone thickening tank through a second connecting elbow, and the first connecting elbow and the second connecting elbow are both provided with centrifugal pumps.

[0015] The present invention also provides an application method of the above-mentioned brine impurity removal equipment, comprising the following steps:

[0016] S1, into the reaction tank, the brine and liquid caustic soda produced after lithium extraction and thallium removal from the lepidolite ore are introduced, and after the pH value of the mixed solution to be detected is between 11.5 and 13, a primary purified liquid is obtained;

[0017] S2, passing the primary purified liquid prepared in S1 into the purified liquid transfer tank through the first chute, and then pumped to the deep cone thickening tank through the first connecting elbow pump, and at the same time, adding the flocculant solution at the entrance of the deep cone thickening tank through the auxiliary agent storage box, fully stirring and separating, to obtain a supernatant and an underflow;

[0018] S3. The supernatant prepared in S2 is passed through the second chute into the inclined tube sedimentation tank. After sufficient sedimentation, underflow and filtrate are obtained. The filtrate is passed through the third chute into the inclined tube transfer tank to obtain brine after impurities are removed. The underflow is pumped through the second connecting elbow to the deep cone thickening tank for further separation.

[0019] According to the application method provided by the present invention, the mass fraction of the liquid caustic soda in S1 is 32%.

[0020] According to the application method provided by the present invention, the mass volume ratio of water and flocculant in the flocculant solution in S2 is 1000:1-3, the volume ratio of the primary purified liquid to the flocculant solution is 1000:0.3-1, and the stirring speed of the deep cone thickening tank is 45rpm / min.

[0021] According to the application method provided by the present invention, the stirring and separation time in S2 is 45 to 60 minutes, and the sufficient sedimentation time in S3 is 45 to 60 minutes.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] (1) The present invention provides a brine impurity removal equipment, including a stepped continuous purification tank, a deep cone thickening tank and an inclined tube sedimentation tank, for removing impurities such as magnesium, ferromanganese and aluminum in brine. The equipment has a large production capacity and a high degree of automation, which is convenient for staff to operate quickly and can also reduce the production cost of the enterprise.

[0024] (2) The present invention also provides an application method of equipment for removing impurities from brine, wherein the pH value of the brine is adjusted by liquid alkali, and then a flocculant is added to remove the impurities magnesium, ferromanganese and aluminum in the brine through a deep cone thickening tank and an inclined tube settling tank. After purification, magnesium is completely removed from the brine, and the contents of ferromanganese and aluminum are reduced to 0.001 g / L. At the same time, the slag rate is greatly reduced to 2‰. The application method solves the technical problems of large amount of impurity slag removed and high cost of lithium recovered from the slag in the prior art, thereby achieving the goal of small amount of impurity slag removed, reduced cost of lithium recovered from the slag and well realizing the purpose of circular economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 Schematic diagram of the structure of equipment for removing impurities from brine.

[0027] Reference numerals:

[0028] 1. Reaction tank; 101. First reaction tank; 102. Second reaction tank; 103. pH detector; 2. Purification liquid transfer tank; 201. First chute; 3. Deep cone thickening tank; 301. First connecting elbow; 302. Second connecting elbow; 303. Auxiliary agent storage box; 4. Inclined tube sedimentation tank; 401. Second chute; 5. Inclined tube transfer tank; 501. Third chute; 6. Centrifugal pump. DETAILED DESCRIPTION

[0029] Example 1

[0030] The present embodiment provides an equipment for removing impurities from brine, comprising: a reaction tank 1; a purified liquid transfer tank 2, whose input end is connected to the output end of the reaction tank 1 through a first chute 201; a deep cone thickening tank 3, whose input end is connected to the output end of the purified liquid transfer tank 2 through a first connecting elbow 301; an inclined tube sedimentation tank 4, whose input end is connected to the upper output end of the deep cone thickening tank 3 through a second chute 401; and an inclined tube transfer tank 5, whose input end is connected to the upper output end of the inclined tube sedimentation tank 4 through a third chute 501.

[0031] In this embodiment, the function of the reaction tank 1 is to mix the liquid alkali with the brine to be removed from the impurities, and to control the pH value of the solution while removing impurities, so as to facilitate the subsequent impurity removal. A stirring structure is arranged in the reaction tank 1, and a pH detector 103 is arranged at the output port of the reaction tank 1. The solution will be passed into the purified liquid transfer tank 2 only after the pH value of the solution at the outlet of the reaction tank 1 is detected to be within a suitable range. The input end of the reaction tank 1 is at the top of the reaction tank 1, and the output end of the reaction tank 1 is at the upper side wall of the reaction tank 1.

[0032] The reaction tank 1 is provided with one or multiple reaction tanks are provided in series, and the multiple reaction tanks include a first reaction tank 101, a second reaction tank 102, and a third reaction tank, etc. The output end of the first reaction tank 101 is connected to the input end of the second reaction tank 102, and the output end of the second reaction tank 102 is connected to the input end of the third reaction tank 1, and so on. The output end of the last reaction tank 1 in series is connected to the input end of the purified liquid transfer tank 2. When multiple reaction tanks 1 are provided in series, the reaction tanks 1 are connected in a stepped manner, the output end of the first reaction tank 101 is provided on the side wall of the first reaction tank 101, the input end of the second reaction tank 102 is provided at the top of the second reaction tank 102, and the feed end of the first reaction tank 101 is connected to a feed device, and the number of the feed devices is determined according to the required raw materials.

[0033] The first chute 201 is a connecting transfer trough, one end of which is connected to the upper side wall output end of the reaction tank 1, and the other end is connected to the upper side wall input end of the purified liquid transfer trough 2. The bottom side wall output end of the purified liquid transfer trough 2 is connected to the top input end of the deep cone thickening trough 3 through the first connecting elbow 301. The input end of the deep cone thickening trough 3 is also provided with an inlet for a flocculant solution, and the inlet is connected to an auxiliary agent storage box 303. The flocculant solution is stored in the auxiliary agent storage box 303. The deep cone thickening trough 3 is a deep cone thickener, which functions to fully and evenly stir the solution introduced into the purified liquid transfer trough 2 with the flocculant solution, separate the slag liquid, and obtain a supernatant and an underflow. The underflow is removed through the bottom outlet of the deep cone thickening trough 3 and enters the diaphragm filter press. The filter press residue enters the ton bag through the slag unloading hopper to re-leach and recover lithium.

[0034] The reaction tank 1 and the purified liquid transfer tank 2 are combined into a step-type continuous purification tank, and the step-type continuous evolution tank, the deep cone thickening tank 3, the inclined tube sedimentation tank 4 and the inclined tube transfer tank 5 are connected in series to obtain equipment for removing impurities from brine, which is used to remove impurities such as magnesium, ferromanganese and aluminum in the brine. The step-type continuous purification tank performs purification, and the deep cone thickening tank 3 and the inclined tube sedimentation tank 4 perform solid-liquid separation.

[0035] The upper side wall output end of the deep cone thickening tank 3 is connected with the upper side wall input end of the inclined tube sedimentation tank 4 through the second chute 401. The inclined tube sedimentation tank 4 includes a top trough, a flow tube and a sedimentation box. The top trough is arranged at the top of the sedimentation box. The width of the left side of the top trough is greater than the width of the sedimentation box. The top trough is connected with one end of the flow tube fixed on the left side of the sedimentation box at the bottom end of the left side of the sedimentation box where it exceeds the top trough. The other end of the flow tube is connected with the bottom input end of the sedimentation box. A plurality of inclined tubes are arranged in the sedimentation box. The liquid flowing into the sedimentation box flows from the bottom to the top in the sedimentation box. The solution in the sedimentation box is sedimented to obtain filtrate and underflow. The output end at the top of the sedimentation box is connected with the third chute 501. The other end of the third chute 501 is connected with the inclined tube transfer tank 5. The filtrate flows into the inclined tube transfer tank 5 through the third chute 501.

[0036] The bottom output end of the sedimentation box outputs the bottom flow, and the bottom flow flows back to the deep cone thickening tank 3 through the second connecting elbow 302 which is connected between the bottom output end of the inclined tube sedimentation tank 4 and the top input end of the deep cone thickening tank 3. Centrifugal pumps 6 are provided on the first connecting elbow 301 and the second connecting elbow 302.

[0037] The equipment for removing impurities from brine provided in this embodiment has a high degree of automation and a large production capacity. The equipment can be used to purify the brine produced after lithium extraction and thallium removal from lepidolite ore. It has better separation effect, better slag properties and easier slag unloading than the existing slag-liquid separation using a filter press.

[0038] Example 2

[0039] This embodiment provides an application method of the equipment for removing impurities from brine provided in Embodiment 1, and the specific steps are as follows:

[0040] S1, into the first reaction tank, the brine produced after lithium extraction and thallium removal from the lepidolite ore is introduced, and the mass fraction of 32% of liquid caustic soda is added simultaneously, and the pH value of the solution at the outlet of the first reaction tank is detected to be 10, and the solution is passed into the second reaction tank, and the mass fraction of 32% of liquid caustic soda is continued to be added to the second reaction tank, and the pH value of the solution at the outlet of the second reaction tank is detected to be 12, and a purified liquid is obtained;

[0041] S2, mixing water and flocculant polyacrylamide in a mass volume ratio of 1000:2 to prepare a flocculant solution, the primary purified liquid prepared in S1 flows into the purified liquid transfer tank through the first chute, and then is transported to the deep cone thickening tank through the centrifugal pump of the first connecting elbow, and the flocculant solution is simultaneously added to the input end of the deep cone thickening tank through the auxiliary agent storage box, the volume ratio of the primary purified liquid to the flocculant solution is 1000:0.7, the stirring speed of the deep cone thickening tank is adjusted to 45rpm / min, and the residue liquid is separated by sufficient stirring and separation for 55min to obtain a supernatant and an underflow, and the underflow enters the diaphragm filter press;

[0042] S3. The supernatant prepared in S2 is passed through the second chute into the top trough of the inclined tube settling tank, and flows into the interior of the settling tank through the flow pipe for sedimentation. After sufficient sedimentation for 52 minutes, the bottom flow and filtrate of the inclined tube settling tank are obtained. The bottom flow of the inclined tube settling tank is returned to the deep cone thickening tank, and the filtrate is passed through the third chute into the inclined tube transfer tank. The filtrate is the brine after impurities are removed.

[0043] In the method provided in this embodiment, liquid alkali is used for purification and impurity removal, and the amount of slag is small, the slag rate is 2‰, and purification is carried out by a stepped continuous purification tank, and solid-liquid separation is carried out by a deep cone thickening tank and an inclined tube sedimentation tank. The liquid-solid separation effect is good, the amount of slag is small, the slag property is good, and the slag is easy to unload. The cost of recovering lithium in the slag, that is, washing the slag, is reduced and the circular economy is well realized. The continuous purification tank has a large production capacity and a high degree of automation.

[0044] The raw material used for purification in this embodiment is the brine produced after lithium extraction and thallium removal from lepidolite ore. The impurities purified are magnesium, ferromanganese and aluminum. The contents of magnesium, ferromanganese and aluminum in the brine after purification are 0.0001 g / L, 0.0001 g / L and 0.001 g / L, respectively.

[0045] Example 3

[0046] This embodiment provides an application method of the equipment for removing impurities from brine provided in Embodiment 1, and the specific steps are as follows:

[0047] S1, introducing brine produced by extracting lithium from lepidolite and removing thallium into a reaction tank, adding 32% liquid caustic soda by mass simultaneously, and detecting that the pH value at the outlet of the reaction tank is 11.5, to obtain a primary purified liquid;

[0048] S2. Mix water and flocculant polyacrylamide in a mass volume ratio of 1000:1 to prepare a flocculant solution. The primary purified liquid prepared in S1 flows into the purified liquid transfer tank through the first chute, and then is transported to the deep cone thickening tank through the centrifugal pump of the first connecting elbow. At the same time, the flocculant solution is synchronously added to the input end of the deep cone thickening tank through the auxiliary agent storage box. The volume ratio of the primary purified liquid to the flocculant solution is 1000:0.3. The stirring speed of the deep cone thickening tank is adjusted to 45rpm / min. The residue liquid is fully stirred and separated for 45min. The residue liquid is separated to obtain a supernatant and an underflow, and the underflow enters the membrane filter press;

[0049] S3. The supernatant prepared in S2 is passed through the second chute into the top trough of the inclined tube settling tank, and flows into the interior of the settling tank through the flow pipe for sedimentation. After sufficient sedimentation for 45 minutes, the bottom flow and filtrate of the inclined tube settling tank are obtained. The bottom flow of the inclined tube settling tank is returned to the deep cone thickening tank, and the filtrate is passed through the third chute into the inclined tube transfer tank. The filtrate is the brine after impurities are removed.

[0050] In the method provided in this embodiment, liquid alkali is used for purification and impurity removal, and the amount of slag is small, the slag rate is 2‰, and purification is carried out by a stepped continuous purification tank, and solid-liquid separation is carried out by a deep cone thickening tank and an inclined tube sedimentation tank. The liquid-solid separation effect is good, the amount of slag is small, the slag property is good, and the slag is easy to unload. The continuous purification tank has a large production capacity and a high degree of automation.

[0051] The raw material used for purification in this embodiment is the brine produced after lithium extraction and thallium removal from lepidolite ore. The impurities purified are magnesium, ferromanganese and aluminum. The contents of magnesium, ferromanganese and aluminum in the brine after purification are 0.0001 g / L, 0.0001 g / L and 0.001 g / L, respectively.

[0052] Example 4

[0053] This embodiment provides an application method of the equipment for removing impurities from brine provided in Embodiment 1, and the specific steps are as follows:

[0054] S1, introducing brine produced by extracting lithium from lepidolite and removing thallium into a reaction tank, adding 32% liquid caustic soda by mass simultaneously, and detecting that the pH value at the outlet of the reaction tank is 13, to obtain a primary purified liquid;

[0055] S2, mixing water and flocculant polyacrylamide in a mass volume ratio of 1000:3 to prepare a flocculant solution, the primary purified liquid prepared in S1 flows into the purified liquid transfer tank through the first chute, and then is transported to the deep cone thickening tank through the centrifugal pump of the first connecting elbow, and the flocculant solution is simultaneously added to the input end of the deep cone thickening tank through the auxiliary agent storage box, the volume ratio of the primary purified liquid to the flocculant solution is 1000:1, the stirring speed of the deep cone thickening tank is adjusted to 45rpm / min, and the residue liquid is fully stirred and separated for 60min, and the residue liquid is separated to obtain a supernatant and an underflow, and the underflow enters the membrane filter press;

[0056] S3. The supernatant prepared in S2 is passed through the second chute into the top trough of the inclined tube settling tank, and flows into the interior of the settling tank through the flow pipe for sedimentation. After sufficient sedimentation for 60 minutes, the bottom flow and filtrate of the inclined tube settling tank are obtained. The bottom flow of the inclined tube settling tank is returned to the deep cone thickening tank, and the filtrate is passed through the third chute into the inclined tube transfer tank. The filtrate is the brine after impurities are removed.

[0057] In the method provided in this embodiment, liquid alkali is used for purification and impurity removal, and the amount of slag is small, the slag rate is 2‰, and purification is carried out by a stepped continuous purification tank, and solid-liquid separation is carried out by a deep cone thickening tank and an inclined tube sedimentation tank. The liquid-solid separation effect is good, the amount of slag is small, the slag property is good, and the slag is easy to unload. The continuous purification tank has a large production capacity and a high degree of automation.

[0058] The raw material used for purification in this embodiment is the brine produced after lithium extraction and thallium removal from lepidolite ore. The impurities purified are magnesium, ferromanganese and aluminum. The contents of magnesium, ferromanganese and aluminum in the brine after purification are 0.0001 g / L, 0.0001 g / L and 0.001 g / L, respectively.

[0059] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent change made to the above embodiment according to the technical essence of the invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A brine impurity removal device, characterized in that: include: Reaction tank (1); A purified liquid transfer tank (2), the input end of which is connected to the output end of the reaction tank (1) via a first chute (201); A deep cone thickening tank (3), the input end of which is connected to the output end of the purified liquid transfer tank (2) via a first connecting elbow (301); An inclined tube sedimentation tank (4), the input end of which is connected to the upper output end of the deep cone thickening tank (3) via a second chute (401); The input end of the inclined tube transfer tank (5) is connected to the upper output end of the inclined tube sedimentation tank (4) through a third chute (501).

2. The equipment for removing impurities from brine according to claim 1, characterized in that: The reaction tank (1) is provided with one or a plurality of reaction tanks (1) are provided in series, and a pH detector (103) is provided at the output port of the reaction tank (1).

3. The equipment for removing impurities from brine according to claim 1, characterized in that: The input end of the deep cone thickening tank (3) is also provided with a liquid inlet, and the liquid inlet is connected to an auxiliary agent storage box (303).

4. The equipment for removing impurities from brine according to claim 1, characterized in that: The bottom of the inclined tube settling tank (4) is connected to the input end of the deep cone thickening tank (3) via a second connecting elbow (302), and the first connecting elbow (301) and the second connecting elbow (302) are both provided with a centrifugal pump (6).

5. An application method of the equipment for removing impurities from brine as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: S1, introducing brine and liquid caustic soda produced after lithium extraction and thallium removal from lepidolite into a reaction tank (1), and obtaining a primary purified liquid after the pH value of the mixed solution is detected to be between 11.5 and 13; S2, passing the primary purified liquid prepared in S1 into the purified liquid transfer tank (2) through the first chute (201), and then pumped into the deep cone thickening tank (3) through the first connecting elbow (301), and at the same time, adding the flocculant solution through the auxiliary agent storage box (303) at the inlet of the deep cone thickening tank (3), fully stirring and separating, and obtaining a supernatant and an underflow; S3, the supernatant prepared in S2 is passed through the second chute (401) into the inclined tube settling tank (4), and after sufficient sedimentation, an underflow and a filtrate are obtained. The filtrate is passed through the third chute (501) into the inclined tube transfer tank (5) to obtain brine after impurities are removed. The underflow is pumped through the second connecting elbow (302) to the deep cone thickening tank (3) for further separation.

6. The application method according to claim 5, characterized in that: The mass fraction of the liquid caustic soda in S1 is 32%.

7. The application method according to claim 5, characterized in that: The mass volume ratio of water and flocculant in the flocculant solution in S2 is 1000:1-3, the volume ratio of the primary purified liquid to the flocculant solution is 1000:0.3-1, and the stirring speed of the deep cone thickening tank (3) (3) is 45rpm / min.

8. The application method according to claim 5, characterized in that: The stirring and separation time in S2 is 45 to 60 minutes, and the sufficient sedimentation time in S3 is 45 to 60 minutes.

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