Synergistic decalcification and carbon sequestration method for high-calcium chloride type lithium-containing brine

Abstract

Aiming at the problems of difficult decalcification and carbon sequestration of the high-calcium chloride type lithium-containing brine, carbon emission in production activities and the like, the method comprises the following steps: decalcification: mixing and stirring the high-calcium chloride type lithium-containing brine and a sodium / potassium carbonate solution generated by sodium / potassium hydroxide absorption tail gas to react; or discharging into a salt pond to evaporate to naturally settle the calcium carbonate solid, or directly carrying out solid-liquid separation to obtain calcium carbonate and decalcified brine; evaporating to remove sodium / potassium: evaporating and precipitating the decalcified brine to obtain recoverable sodium chloride / sylvinite and sodium / potassium removed brine; purifying and electrolyzing: washing, dissolving and purifying the sodium / sylvite, and electrolyzing to obtain a sodium / potassium hydroxide solution and hydrochloric acid; carbon capture: taking the sodium / potassium hydroxide solution as an absorption solution to capture carbon dioxide in tail gas generated by fossil energy in the production process to obtain a sodium / potassium carbonate solution, and after carbon dioxide is removed from the tail gas, further treating the tail gas and discharging the tail gas after reaching the standard. The method has the advantages that calcium in the lithium-containing brine can be removed, carbon can be fixed at the same time, carbon emission generated in production activities is reduced, comprehensive utilization of resources is achieved, and the like.

Description

Technical Field

[0001] The present invention relates to a method for synergistic carbon fixation and decalcification of high-calcium chloride-type lithium-containing brine, and in particular to a method for comprehensive resource utilization of calcium ions in the brine as a carbon dioxide fixative in tail gas, while removing calcium from the brine and fixing carbon dioxide in the tail gas. Background Art

[0002] Carbon dioxide is one of the most important greenhouse gases. According to the International Energy Agency's "Global Energy Sector 2050 Net Zero Emissions Roadmap" report, under the established policy scenario, carbon dioxide emissions are expected to rise from 34Gt in 2020 to 36Gt by 2030, and will remain at roughly the same level until 2050. If emissions continue to develop on this trajectory after 2050, there is a 50% probability that the global average surface temperature will rise by 2.7℃ by 2100, which will cause icebergs to melt, sea levels to rise, and some coastal cities to be flooded. To this end, the Paris Agreement was adopted at the United Nations Climate Summit on December 12, 2015 to replace the Kyoto Protocol. The goal is to control the increase in global average temperature this century to within 2℃ compared with the pre-industrial period, and strive to limit the temperature increase to within 1.5℃. To achieve this goal, major countries have set dual carbon targets. Technically speaking, it is mainly to reduce carbon emissions during the use of fossil energy or use non-carbon energy instead, so as to reduce emissions from the source. However, for some carbon dioxide that has to be emitted, it needs to be controlled from the tail end through technologies such as physical carbon fixation, biological carbon fixation, carbon capture, utilization and storage.

[0003] Among them, carbon capture, utilization and storage technology is a new development trend of carbon capture and storage technology. It captures the carbon dioxide generated in the production process and uses it as a resource for comprehensive utilization, which can not only generate economic benefits but also be more practical. Calcium ions can react with carbon dioxide at a suitable pH to produce insoluble calcium carbonate, so it is one of the main ways to capture and store carbon dioxide. For example, alkaline soil contains a lot of calcium ions, which can combine with carbon dioxide in the atmosphere to form calcium carbonate precipitation during precipitation. In addition to nature, the use of calcium ions for carbon fixation has also gradually gained attention in academia and industry. For example, Yuan Junsheng's team in Inorganic Salt Industry, 2017, 49(5), 48 and patent CN104108803 A disclosed "using white mud discharged in the process of producing soda ash by the ammonia-soda method as an alkali source, and carbon dioxide as a precipitant to remove calcium and magnesium from seawater. The seawater after decalcification and magnesium removal can be used as a raw material for seawater desalination"; patent CN116988839 A disclosed "a method for storing CO2 and fixing carbon using abandoned salt caverns storing alkali slag". This method is to collect and compress carbon dioxide and then inject it into abandoned salt caverns storing alkali slag. The technology is feasible, but it is a gas-liquid-solid three-phase reaction process; patent CN 117654255 A disclosed "a repetitive and efficient carbon fixation method based on seawater", which is to pass carbon dioxide-containing gas into seawater, then add a carbon fixer made by mixing calcined dolomite, magnesium chloride, calcium oxide and calcium chloride, and repeatedly pass carbon dioxide-containing gas or add a carbon fixer according to the pH change to accelerate the dissolution of the effective ingredients in the carbon fixer, while improving the carbonization efficiency of the carbon fixer and the removal rate of carbon dioxide. All of the above require different methods to improve the reaction efficiency due to the use of solid alkaline substances and gas-liquid-solid three-phase reactions.

[0004] High calcium chloride brine has a high Ca content and contains almost no CO3 2- and HCO3 - , SO4 2- It has a very low content and is a brine resource with a high mineralization of 100-300g / L, rich in a variety of valuable elements K, B, Li, Sr, Br, I or heavy metal elements Fe, Mn, Cu, Pb, Zn, Ba. It is mainly distributed in major sedimentary basins, mid-ocean ridge hydrothermal fluids and continental tectonic activity zones. At the same time, it is also a potential high-efficiency carbon fixer.

[0005] Traditional evaporation precipitation is still one of the main production processes for lithium extraction from salt lakes due to its low investment cost and low unit consumption of fresh water resources. However, research and industrial production practice have shown that it is more difficult to extract lithium from high-calcium chloride brine than from high-magnesium brine using traditional methods. So far, it has only been industrially applied in Argentina's 3Q Salt Lake. If the carbon dioxide and sodium chloride produced in the production process can be comprehensively utilized, sodium hydroxide and hydrochloric acid can be prepared by electrolyzing sodium chloride, and sodium hydroxide can be used to absorb carbon dioxide in the tail gas to generate sodium carbonate for removing calcium from the brine. At the same time, the brine can be acidified with hydrochloric acid to remove and recover boron in the brine, achieving efficient and comprehensive utilization of resources is a preferred option.

[0006] Therefore, it is particularly urgent and of great significance to seek a method for synergistic decalcification and carbon fixation of high-calcium chloride-containing lithium brine. Summary of the invention

[0007] The task of the present invention is to overcome the deficiencies of the prior art and to provide a method for coordinated decalcification and carbon fixation of high-calcium chloride type lithium-containing brine, which can not only remove calcium from such lithium-containing brine, but also fix carbon at the same time, thereby reducing carbon emissions generated in production activities and realizing comprehensive resource utilization.

[0008] The task of the present invention is accomplished by the following technical solutions:

[0009] The method for synergistic decalcification and carbon fixation of high-calcium chloride-type lithium-containing brine is aimed at the problems of difficult decalcification and carbon fixation of high-calcium lithium-containing brine and carbon emissions generated in production activities. The specific process steps are as follows:

[0010] A. Carbon fixation and decalcification: high calcium chloride type lithium-containing brine is mixed with sodium carbonate / potassium solution produced by sodium hydroxide / potassium absorbing tail gas, stirred and reacted, or discharged into a salt pond for evaporation to allow calcium carbonate solids to settle naturally, or directly separated into solid and liquid to obtain calcium carbonate and decalcified brine;

[0011] B. Evaporation to remove sodium / potassium, evaporate and precipitate the decalcified brine to obtain recoverable sodium chloride / sylvite and desodium / potassium brine;

[0012] C. Purification electrolysis: the sodium / potassium salt is washed, dissolved, purified and then electrolyzed to obtain sodium hydroxide / potassium solution and hydrochloric acid.

[0013] D. Carbon capture: Sodium hydroxide / potassium hydroxide solution is used as an absorption liquid to capture carbon dioxide in the tail gas generated by the use of fossil energy in the production process to obtain sodium carbonate / potassium carbonate solution. After the carbon dioxide is removed from the tail gas, it is further treated to meet emission standards.

[0014] Compared with the prior art, the present invention has the following advantages or effects:

[0015] Because the waste gas and waste residue generated in the production process are fully utilized, brine decalcification and tail gas carbon fixation are coordinated, and acids and alkalis are produced on site, it can reduce dependence on the outside world and achieve efficient and comprehensive utilization of resources; at the same time, since the high-calcium chloride-type lithium-containing brine is decalcified in advance, potential problems in the process of high-calcium brine concentration, impurity removal and lithium extraction are avoided, so that the traditional method of lithium extraction from high-calcium chloride brine increases efficiency and reduces emissions; in addition, due to the simple process flow, the investment is small and the effect is fast.

[0016] The high-calcium chloride type lithium-containing brine involved in the application documents is high-calcium chloride type lithium-containing brine raw brine, high-calcium chloride type lithium-containing brine pre-concentrated brine after de-sodiumization, and high-calcium chloride type lithium-containing brine pre-concentrated brine after de-sodium / potassiumization; the high-purity lithium salt is lithium chloride, lithium hydroxide or lithium carbonate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the process flow of the principle of a method for coordinated decalcification and carbon fixation of high-calcium chloride-type lithium-containing brine proposed by the present invention.

[0018] Figure 2 So Figure 1 The method for coordinated decalcification and carbon fixation of high-calcium chloride-type lithium-containing brine is used as a schematic diagram of the process flow of direct solid-liquid separation of calcium carbonate and decalcified brine after the reaction of raw brine with sodium carbonate in Example 1.

[0019] Figure 3 So Figure 1 The process flow chart of the high calcium chloride type lithium-containing brine coordinated decalcification and carbon fixation method is used in Example 2, where the raw brine reacts with sodium carbonate and then is transported to the salt pond for evaporation to continue reaction and sodium / potassium removal.

[0020] Figure 4 So Figure 1 The method for coordinated decalcification and carbon fixation of high-calcium chloride-type lithium-containing brine is used in the process flow chart of Example 3 for direct solid-liquid separation of calcium carbonate and decalcified brine after reaction of pre-concentrated brine for sodium / potassium removal by evaporation with calcium carbonate.

[0021] Figure 5 So Figure 1 The method for coordinated decalcification and carbon fixation of high-calcium chloride-containing lithium brine is used in Example 4. After the pre-concentrated brine for sodium / potassium removal by evaporation reacts with calcium carbonate, the brine is transported to the salt pond for further reaction and sodium removal process flow chart.

[0022] The present invention is further described in detail below in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0023] like Figure 1-5 As shown in the figure, the method for coordinated decalcification and carbon fixation of high-calcium chloride-type lithium-containing brine is aimed at the problems of difficult decalcification and carbon fixation of high-calcium lithium-containing brine and carbon emissions generated in production activities. The specific process steps are as follows:

[0024] A. Carbon fixation and decalcification: high calcium chloride type lithium-containing brine is mixed with sodium carbonate / potassium solution produced by sodium hydroxide / potassium absorbing tail gas, stirred and reacted, or discharged into a salt pond for evaporation to allow calcium carbonate solids to settle naturally, or directly separated into solid and liquid to obtain calcium carbonate and decalcified brine;

[0025] B. Evaporation to remove sodium / potassium, evaporate and precipitate the decalcified brine to obtain recoverable sodium chloride / sylvite and desodium / potassium brine;

[0026] C. Purification electrolysis: the sodium / potassium salt is washed, dissolved, purified and then electrolyzed to obtain sodium hydroxide / potassium solution and hydrochloric acid.

[0027] D. Carbon capture: Sodium hydroxide / potassium hydroxide solution is used as an absorption liquid to capture carbon dioxide in the tail gas generated by the use of fossil energy in the production process to obtain sodium carbonate / potassium carbonate solution. After the carbon dioxide is removed from the tail gas, it is further treated to meet emission standards.

[0028] The process of the present invention may further be:

[0029] In step A, the calcium carbonate is separated into solid and liquid, dehydrated and then sealed or comprehensively utilized.

[0030] The solid-liquid separation method of calcium carbonate in step A is one or any combination of common solid-liquid separation methods such as plate and frame filter pressing, belt filtration, vacuum filtration, centrifugal filtration, and natural sedimentation.

[0031] The decalcified brine in step A is used for subsequent impurity removal and lithium recovery.

[0032] The separation method of the sodium / potassium salt in step B and the calcium carbonate in step A is one or any combination of gravity separation methods commonly used in production, such as a shaking table and a hydrocyclone.

[0033] The calcium carbonate dehydration method in step B is one or any combination of common solid-liquid separation methods in production, such as plate and frame filter pressing, belt filtration, vacuum filtration, centrifugal filtration, etc.

[0034] In step C, the purification of the sodium chloride / potassium solution is carried out by using one or a combination of coagulation sedimentation method, chemical method, membrane separation, and ion exchange resin method, which can remove impurities such as insoluble matter and divalent ions in the solution.

[0035] In step C, a bipolar membrane is used to electrolyze a sodium chloride / potassium solution to prepare sodium hydroxide / potassium and hydrochloric acid.

[0036] In step C, the separation method of sodium chloride / sylvite and calcium carbonate is one or a combination of common gravity separation methods such as a shaking table and a hydrocyclone.

[0037] In step C, the sodium-potassium removal brine purification adopts chemical method, nanofiltration, electrodialysis or ion exchange resin method to remove the residual impurity ions in the brine.

[0038] The hydrochloric acid in step C and the sodium / potassium removal brine in step B are evaporated, concentrated and impurity removed, and then acidified, boron is recovered, impurities are deeply removed, and lithium is extracted in sequence to obtain lithium salt.

[0039] The sodium carbonate / potassium solution in step D is returned to the high calcium chloride type lithium-containing brine to continue the cycle in step A.

[0040] The stirring reaction time of the high calcium chloride type lithium-containing brine in step A and the sodium carbonate / potassium carbonate solution in step D is 5 to 60 minutes.

[0041] The stirring reaction temperature of the high calcium chloride type lithium-containing brine in step A and the sodium carbonate / potassium solution in step D is the brine temperature ~ 70°C.

[0042] Example 1

[0043] Reference Figure 2 , the original brine reacts with sodium carbonate to directly separate calcium carbonate and decalcified brine, comprising the following steps:

[0044] Step A. High calcium chloride type lithium-containing brine (Ca 2+ 3.26%, Na + 6.21%, K + 0.66%, Li + 0.07%、Cl - 16.74%, SO4 2- 0.02%, H3BO3 0.56%) and 1.1 times the chemical equivalent of sodium carbonate solution were stirred for 60 minutes.

[0045] Step B. After the brine slurry after the reaction is thickened, a belt vacuum filter is used for solid-liquid separation and washing of calcium carbonate. The calcium carbonate slag after washing and dehydration is stored in a slag yard for sealing or comprehensive utilization. The decalcified brine is pumped to an evaporation pond for further sodium and potassium removal, boron recovery, etc. to obtain concentrated brine. After further impurity removal in a processing plant, the purified high-lithium brine is used to produce battery-grade lithium carbonate, lithium hydroxide, lithium chloride and other lithium salt products.

[0046] Step C. drain the evaporation pool for removing sodium and potassium at a fixed period, then collect sodium / potassium rock salt, crush, wash, dissolve, purify, etc., to obtain sodium chloride / potassium solution, which is electrolyzed in a bipolar membrane device to obtain sodium hydroxide and hydrochloric acid solution. The sodium hydroxide / potassium solution is used to absorb carbon dioxide in the tail gas generated during the use of petrochemical raw materials to produce sodium carbonate solution for reuse in step 1; hydrochloric acid is used to acidify brine to recover boron.

[0047] Example 2

[0048] After the reaction between the raw brine and sodium carbonate, the brine is transported to the salt pool for evaporation and further reaction and removal of sodium / potassium. For the specific process flow, refer to Figure 3 , including the following steps:

[0049] Step A. High calcium chloride type lithium-containing halogen (Ca 2+ 3.26%, Na + 6.21%, K + 0.66%, Li + 0.07%、Cl - 16.74%, SO4 2- 0.02%, H3BO3 0.56%) and 1.2 times the chemical equivalent of sodium carbonate solution were stirred for reaction for 10 minutes.

[0050] Step B. The brine after the reaction is pumped to the evaporation pond for further sodium and potassium removal, boron recovery, etc. to obtain concentrated brine. After further impurity removal in the processing plant, the purified high-lithium brine is used to produce battery-grade lithium carbonate, lithium hydroxide, lithium chloride and other lithium salt products.

[0051] Step C. draining the sodium-removed evaporation pool at a fixed period, then collecting the sodium salt in the evaporation pool, crushing and pulping, separating calcium carbonate from the sodium salt by gravity separation equipment, dehydrating the calcium carbonate slurry by a plate and frame filter press, and then storing it in a slag yard for sealing or comprehensive utilization, and further washing, dissolving, and purifying the initially purified sodium salt to obtain a purified sodium chloride solution, which is electrolyzed in a bipolar membrane device to obtain sodium hydroxide and hydrochloric acid solution, and the sodium hydroxide solution is used to absorb carbon dioxide in the tail gas generated during the use of petrochemical raw materials to produce sodium carbonate solution for reuse in step 1;

[0052] Example 3

[0053] After the pre-concentrated brine with sodium / potassium removed by evaporation reacts with calcium carbonate, the calcium carbonate and the decalcified brine are directly separated into solid and liquid, referring to Figure 4 , including the following steps:

[0054] Step A. High calcium chloride type lithium-containing brine (Ca 2+ 3.26%, Na + 6.21%, K + 0.66%、Li + 0.07%、Cl - 16.74%, SO4 2- 0.02%, H3BO3 0.56%) is firstly de-sodiumized and de-potassiumized in the evaporation pond to obtain calcium chloride saturated pre-concentrated brine (Ca 2+ 12.50%, Mg 2+ 0.51%, Na + 0.30%、K + 1.54%, Li+ 0.29%、Cl - 26.99%, SO4 2- 0.00%, H3BO3 2.14%), and stirred with 1.3 times the chemical equivalent of sodium carbonate solution for 45 minutes.

[0055] Step B. After the brine slurry after the reaction is thickened, a centrifuge filter is used for solid-liquid separation and calcium carbonate washing. The calcium carbonate slag after washing and dehydration is stored in a slag yard for sealing or comprehensive utilization. The decalcified brine is pumped to an evaporation pond for further sodium, potassium, magnesium removal, acidification and boron recovery to obtain concentrated brine. After further impurity removal in a processing plant, the purified high-lithium brine is used to produce battery-grade lithium carbonate, lithium hydroxide, lithium chloride and other lithium salt products.

[0056] Step C. drain the evaporation pool for sodium / potassium removal at a fixed period, then collect sodium / potassium rock salt, crush, wash, dissolve, purify, etc. to obtain sodium chloride / potassium solution, electrolyze it in a bipolar membrane device to obtain sodium hydroxide and hydrochloric acid solution, and the sodium hydroxide / potassium solution is used to absorb carbon dioxide in the tail gas generated during the use of petrochemical raw materials to produce sodium carbonate solution for reuse in step 1; hydrochloric acid is used to acidify brine to recover boron.

[0057] Example 4

[0058] After the pre-concentrated brine with sodium / potassium removed by evaporation reacts with calcium carbonate, the brine is transported to the salt pond for further reaction and sodium removal. Figure 5 , including the following steps:

[0059] Step A. High calcium chloride type lithium-containing brine (Ca 2+ 3.26%, Na + 6.21%, K + 0.66%, Li + 0.07%、Cl - 16.74%, SO4 2- 0.02%, H3BO3 0.56%) is firstly de-sodiumized and de-potassiumized in the evaporation pond to obtain calcium chloride saturated pre-concentrated brine (Ca 2+ 12.50%, Mg 2+ 0.51%, Na + 0.30%、K + 1.54%, Li + 0.29%、Cl - 26.99%, SO4 2- 0.00%, H3BO3 2.14%), and 1.25 times the chemical equivalent of sodium carbonate solution were stirred and reacted at 70°C for 5 minutes.

[0060] Step B. The brine after the reaction is pumped to the evaporation pond for further sodium and potassium removal, acidification and boron recovery, etc. to obtain concentrated brine. After further impurity removal in the processing plant, the purified high-lithium brine is used to produce battery-grade lithium carbonate, lithium hydroxide, lithium chloride and other lithium salt products.

[0061] Step C. drain the evaporation pool for sodium / potassium removal at a fixed period, then collect sodium / potassium rock salt, crush, wash, dissolve, purify, etc. to obtain sodium chloride / potassium solution, electrolyze it in a bipolar membrane device to obtain sodium hydroxide and hydrochloric acid solution, and the sodium hydroxide / potassium solution is used to absorb carbon dioxide in the tail gas generated during the use of petrochemical raw materials to produce sodium carbonate solution for reuse in step 1; hydrochloric acid is used to acidify brine to recover boron.

[0062] Step D. Drain the evaporation pool for removing sodium and potassium from the decalcified brine in a fixed cycle, and then collect the mixture of salt and calcium carbonate in the evaporation pool. The mixture can be stored in a slag dump as needed, or the salt and calcium carbonate can be separated in a manner similar to the aforementioned separation method, and then the salt and calcium carbonate are comprehensively utilized respectively.

[0063] As described above, the present invention can be better implemented. The above embodiments are only the best implementation methods of the present invention, but the implementation methods of the present invention are not limited by the above embodiments. Other changes, modifications, replacements, combinations, and simplifications made without departing from the spirit and principle of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for synergistically decalcifying and carbonizing high-calcium chloride-containing lithium brine, which aims to solve the problems of difficult decalcification and carbon fixation of high-calcium lithium-containing brine and carbon emissions generated in production activities, characterized by: The specific process steps are as follows: A. Carbon fixation and decalcification: high calcium chloride type lithium-containing brine is mixed with sodium carbonate / potassium solution produced by sodium hydroxide / potassium absorbing tail gas, stirred and reacted, or discharged into a salt pond for evaporation to allow calcium carbonate solids to settle naturally, or directly separated into solid and liquid to obtain calcium carbonate and decalcified brine; B. Evaporation to remove sodium / potassium, evaporate and precipitate the decalcified brine to obtain recoverable sodium chloride / sylvite and desodium / potassium brine; C. Purification electrolysis: the sodium / potassium salt is washed, dissolved, purified and then electrolyzed to obtain sodium hydroxide / potassium solution and hydrochloric acid. D. Carbon capture: Sodium hydroxide / potassium hydroxide solution is used as an absorption liquid to capture carbon dioxide in the tail gas generated by the use of fossil energy in the production process to obtain sodium carbonate / potassium carbonate solution. After the carbon dioxide is removed from the tail gas, it is further treated to meet emission standards.

2. The method according to claim 1, characterized in that In step A, the calcium carbonate is separated into solid and liquid, dehydrated and then sealed or comprehensively utilized.

3. The method according to claim 1 or 2, characterized in that The solid-liquid separation method of calcium carbonate in step A is one or any combination of common solid-liquid separation methods such as plate and frame filter pressing, belt filtration, vacuum filtration, centrifugal filtration, and natural sedimentation.

4. The method according to claim 1, characterized in that The decalcified brine in step A is used for subsequent impurity removal and lithium recovery.

5. The method according to claim 1, characterized in that The separation methods of the sodium / potassium salt in step B and the calcium carbonate in step A are all one or any combination of gravity separation methods commonly used in production, such as a shaking table and a hydrocyclone.

6. The method according to claim 1, characterized in that The calcium carbonate dehydration method in step B is one or any combination of common solid-liquid separation methods in production, such as plate and frame filter pressing, belt filtration, vacuum filtration, centrifugal filtration, etc.

7. The method according to claim 1, characterized in that Step C: The sodium chloride / potassium solution is purified by coagulation sedimentation, chemical method, membrane separation, ion exchange resin method or any combination thereof, which can remove impurities such as insoluble matter and divalent ions in the solution.

8. The method according to claim 1 or 7, characterized in that In step C, a bipolar membrane is used to electrolyze a sodium chloride / potassium solution to prepare sodium hydroxide / potassium and hydrochloric acid.

9. The method according to claim 1, characterized in that In step C, the sodium chloride / sylvite and calcium carbonate are separated by one or a combination of common gravity separation methods such as a shaking table and a hydrocyclone.

10. The method according to claim 1, characterized in that In step C, the sodium-potassium removal brine purification adopts chemical method, nanofiltration, electrodialysis or ion exchange resin method to remove the residual impurity ions in the brine.

11. The method according to claim 1, characterized in that The hydrochloric acid in step C and the sodium / potassium removal brine in step B are evaporated, concentrated and impurity removed, and then acidified, boron is recovered, impurities are deeply removed, and lithium is extracted in sequence to obtain lithium salt.

12. The method according to claim 1, characterized in that The sodium carbonate / potassium solution in step D is returned to the high calcium chloride type lithium-containing brine to continue the cycle in step A.

13. The method according to claim 1, characterized in that The stirring reaction time of the high calcium chloride type lithium-containing brine in step A and the sodium carbonate / potassium carbonate solution in step D is 5 to 60 minutes.

14. The method according to claim 1 or 13, characterized in that The stirring reaction temperature of the high calcium chloride type lithium-containing brine in step A and the sodium carbonate / potassium solution in step D is the brine temperature ~ 70°C.

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