Method and system for extracting lithium from lithium resource

Abstract

The invention discloses a method for extracting lithium from a lithium resource material, which comprises the following steps: inputting the lithium resource material into a chlorination furnace for chlorination reaction, enabling the outlet temperature of the chlorination furnace to be a second temperature, and enabling the boiling point of a first chloride to be greater than the second temperature and greater than or equal to the boiling point of lithium chloride and greater than the boiling point of a second chloride, separation among different matter states is carried out on the product of the chlorination reaction, so that a first chloride formed by the chlorination reaction of the first recyclable substance exists in a tangible substance form and is used as a first substance to be treated; a second chloride formed after the chlorination reaction of the second recoverable substance and lithium chloride formed after the chlorination reaction of the lithium compound exist in the form of flue gas and serve as a second substance to be treated; and carrying out flue gas cooling and gas-solid separation treatment on the second to-be-treated substance so as to respectively obtain a lithium target product and a second type of recyclable substance target product through flue gas cooling and gas-solid separation treatment.

Description

Technical Field

[0001] The present disclosure relates to a method and system for extracting lithium from a lithium resource. The lithium resource may be a lithium ore, which may contain at least one of spodumene and lepidolite or may be spodumene or lepidolite. The lithium resource may also be a waste battery, especially a waste battery that has been pretreated, and the pretreatment may include anaerobic sublimation, pyrolysis, and cooling processes. Background Art

[0002] Currently, the main method for extracting lithium from lithium ore or waste batteries is hydrometallurgy. This method has a long process flow and has problems such as high cost and high pollution.

[0003] A preparation method and device of lithium chloride are disclosed in the Chinese patent document of publication number CN112351953A, and it is proposed to utilize chlorination reaction to extract lithium chloride after mixing coke and chlorine in spodumene ore. The method and device proposed in the patent document are to generate lithium chloride gas by chlorination reaction in a chlorination furnace and then desublimate the lithium chloride gas to obtain lithium chloride. However, since spodumene ore often also contains elements such as iron, aluminum, silicon, calcium, magnesium (existing in the form of corresponding oxides) in addition to lithium element (existing in the form of lithium oxide), they also have extraction and recovery value, but the method and device proposed in the above-mentioned patent document focus on extracting lithium by chlorination reaction, and other valuable elements cannot be effectively separated and recovered.

[0004] In fact, the iron, aluminum, silicon, calcium, magnesium and other elements in spodumene ore can be converted into corresponding chlorides through chlorination reaction. Among them, the boiling points of the chlorides converted from the oxides of iron, aluminum and silicon through chlorination reaction are much lower than that of lithium chloride, and can be classified as low-boiling point chlorides; while the boiling points of the chlorides converted from the oxides of calcium and magnesium through chlorination reaction are higher than that of lithium chloride, and can be classified as high-boiling point chlorides. If these low-boiling point chlorides and high-boiling point chlorides are to be discharged from the chlorination furnace along with the lithium chloride gas, the output flue gas temperature of the chlorination furnace will be high, the chlorination reaction time will be long, and the subsequent separation of unused chlorides will be more difficult. Summary of the invention

[0005] The purpose of the present disclosure is to provide a method and system for extracting lithium from lithium resources, so as to solve the technical problem mentioned in the above background technology that other valuable elements cannot be fully and effectively separated and recovered when lithium resources such as spodumene are extracted by the chlorination method.

[0006] In a first aspect, a method for extracting lithium from a lithium resource is provided, wherein the lithium resource contains a first type of recyclable substance and a second type of recyclable substance in addition to a lithium compound, and the reactants formed by the lithium compound and the first type of recyclable substance after pyrometallurgy in a first industrial kiln are in the form of tangible substances (referring to solid and / or liquid substances), and the reactants formed by the second type of recyclable substance after pyrometallurgy are in the form of flue gas; the method comprises: inputting the lithium resource into the first industrial kiln for pyrometallurgy, and separating the product of the pyrometallurgy between different physical states, so that the reactants formed by the lithium compound and the first type of recyclable substance after pyrometallurgy are in the form of tangible substances and serve as the first substance to be processed, and the second type of recyclable substance is in the form of tangible substances after pyrometallurgy. The reactant formed after the pyrometallurgical smelting exists in the form of flue gas and serves as the second material to be treated; the first material to be treated is subjected to hydrometallurgical treatment, so as to obtain a lithium target product and a first type of recyclable material target product through the hydrometallurgical treatment, respectively, the lithium target product is obtained by converting the reactant formed after the lithium compound is subjected to the pyrometallurgical smelting as a raw material, and the first type of recyclable material target product is obtained by converting the reactant formed after the first type of recyclable material is subjected to the pyrometallurgical smelting as a raw material; and the second material to be treated is subjected to flue gas cooling and gas-solid separation treatment, so as to obtain the second type of recyclable material target product from the solid obtained by the flue gas cooling and gas-solid separation treatment, and the second type of recyclable material target product is obtained by converting the reactant formed after the second type of recyclable material is subjected to the pyrometallurgical smelting as a raw material.

[0007] Generally speaking, the first industrial kiln is a chlorination furnace, and the pyrometallurgy is used to chlorinate the lithium resource with chlorine. On this basis, the reactant formed by the lithium compound after the chlorination reaction is lithium chloride, the reactant formed by the first type of recyclable material after the chlorination reaction is the first type of chloride, and the reactant formed by the second type of recyclable material after the chlorination reaction is the second type of chloride, the boiling points of the lithium chloride and the first type of chloride are both greater than the first temperature, the boiling points of the second type of chloride are both less than the first temperature, and the outlet temperature of the first industrial kiln (chlorination furnace) is the first temperature. Generally speaking, the temperature of the pyrometallurgy (chlorination reaction) is 800℃-1400℃.

[0008] Specifically, the product of the pyrometallurgical process is separated into different physical states, so that the reactants formed by the lithium compound and the first type of recyclable material after the pyrometallurgical process exist in the form of tangible objects and serve as the first material to be treated, and the reactants formed by the second type of recyclable material after the pyrometallurgical process exist in the form of flue gas and serve as the second material to be treated. This process may include: a process of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace, a process of performing pre-gas-solid separation while controlling the temperature of the furnace gas to the first temperature range to obtain the second material to be treated and pre-gas-solid separation recovered dust, and a process of configuring the slag and the pre-gas-solid separation recovered dust as the first material to be treated.

[0009] Specifically, the process of controlling the temperature of the furnace gas to the first temperature range and performing pre-gas-solid separation to obtain the second substance to be treated and recovering dust by pre-gas-solid separation may include: after at least two stages of furnace gas cooling and dust removal treatment in series, the flue gas output by the last stage of furnace gas cooling and dust removal treatment is used as the second substance to be treated and the dust obtained by each stage of furnace gas cooling and dust removal treatment is used as the pre-gas-solid separation recovered dust, and each stage of furnace gas cooling and dust removal treatment in the at least two stages of furnace gas cooling and dust removal treatment includes the operation of cooling the furnace gas to be dust removed to a set range and then performing dust removal.

[0010] Optionally, at least the last or rearmost stage of the at least two stages of furnace gas cooling and dust removal treatment uses a high-temperature gas filtering device, and the high-temperature gas filtering device is equipped with a filter element for physically intercepting the gas to be filtered, and the filter element is a metal filter element or a ceramic filter element.

[0011] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0012] Specifically, the second material to be treated is subjected to flue gas cooling and gas-solid separation treatment, so as to obtain the second type of recyclable material target product from the solid obtained by the flue gas cooling and gas-solid separation treatment, which may include: through at least two stages of flue gas cooling and dust removal treatment connected in series, the dust obtained by each stage of flue gas cooling and dust removal treatment is separately used as a target product among the second type of recyclable material target products, and each stage of the flue gas cooling and dust removal treatment in the at least two stages of flue gas cooling and dust removal treatment includes the operation of cooling the flue gas to be dusted to a set range and then performing dust removal.

[0013] Optionally, at least the frontmost or preceding stage of the at least two stages of flue gas cooling and dust removal treatment uses a high-temperature gas filtration device, and the high-temperature gas filtration device is equipped with a filter element for physically intercepting the gas to be filtered, and the filter element is a metal filter element or a ceramic filter element.

[0014] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0015] Specifically, the first substance to be treated is subjected to hydrometallurgical treatment, thereby obtaining a lithium target product and a first type of recyclable substance target product respectively through the hydrometallurgical treatment, which may include: configuring the first substance to be treated into a solution and then mixing it with a chemical precipitant so that the lithium compound and one of the first type of recyclable substances selectively react with the chemical precipitant and precipitate in the form of a precipitate, and then obtaining the lithium target product and the first type of recyclable substance target product respectively through solid-liquid separation.

[0016] Generally speaking, water is used as a solvent, the first substance to be treated is used as a solute, and the first substance to be treated is configured as brine to serve as the solution.

[0017] Specifically, the lithium resource may be a lithium ore (usually at least one of spodumene and lepidolite), then: if the lithium ore contains calcium, the first type of chloride contains calcium chloride; if the lithium ore contains magnesium, the first type of chloride contains magnesium chloride; if the lithium ore contains zinc, the first type of chloride contains zinc chloride; if the lithium ore contains cesium, the first type of chloride contains cesium chloride; if the lithium ore contains rubidium, the first type of chloride contains rubidium chloride; if the lithium ore contains potassium, the first type of chloride contains potassium chloride; if the lithium ore contains sodium, the first type of chloride contains sodium chloride; if the lithium ore contains manganese, the first type of chloride contains manganese chloride; if the lithium ore contains zirconium, the second type of chloride contains zirconium chloride; if the lithium ore contains aluminum, the second type of chloride contains aluminum chloride; if the lithium ore contains silicon, the second type of chloride contains silicon tetrachloride; if the lithium ore contains iron, the second type of chloride contains iron chloride.

[0018] Optionally, the first temperature is greater than the boiling point of ferric chloride and less than the boiling point of lithium chloride. Optionally, the first temperature is 350°C-700°C; or, the first temperature is 350°C-600°C; or, the first temperature is 350°C-450°C.

[0019] Optionally, one stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of ferric chloride and higher than the boiling point of aluminum chloride, and then perform dust removal to recover ferric chloride dust, and another stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of aluminum chloride and higher than the boiling point of silicon tetrachloride, and then perform dust removal to recover aluminum chloride dust.

[0020] Optionally, the tail gas after the at least two-stage flue gas cooling and dust removal treatment is further cooled to a temperature lower than the boiling point of silicon tetrachloride and then silicon tetrachloride is obtained through gas-liquid separation.

[0021] Optionally, after separating the sodium chloride in the first category of recyclable material target products, the separated sodium chloride is used as a raw material to produce sodium hydroxide, chlorine and hydrogen through a chlor-alkali process, and then the chlorine is used for the chlorination reaction, and the hydrogen is reacted with the silicon tetrachloride to produce silicon.

[0022] Optionally, the chemical precipitant comprises an alkali, and the first type of recyclable material reacts with the alkali to precipitate in the form of hydroxide; and / or, the chemical precipitant comprises a chelating agent and sodium carbonate, and the lithium compound reacts with the chelating agent and sodium carbonate to precipitate in the form of lithium carbonate.

[0023] Optionally, the lithium resource is waste batteries that have been pretreated, and the pretreatment includes anaerobic sublimation, pyrolysis, and cooling of the waste batteries.

[0024] Optionally, before the lithium resource is input into the first industrial furnace for the pyrometallurgical smelting, the lithium resource is first input into the second industrial furnace for heating pretreatment.

[0025] The preheating treatment may include further purification and crushing of lithium resources, gasification and separation of organic matter, and the like.

[0026] In a second aspect, a system for extracting lithium from lithium resources is provided, comprising: a pyrometallurgical section, a hydrometallurgical treatment section, and a flue gas cooling and gas-solid separation treatment section, wherein the hydrometallurgical treatment section and the flue gas cooling and gas-solid separation treatment section are respectively connected to the pyrometallurgical section to implement the method for extracting lithium from lithium resources of the first aspect.

[0027] Optionally, the pyrometallurgical part is deployed as a pyrometallurgical workshop, the hydrometallurgical treatment part is deployed as a hydrometallurgical workshop, and the flue gas cooling and gas-solid separation treatment part is deployed as a flue gas cooling and gas-solid separation workshop; in addition, it also includes a silicon making workshop and a chlor-alkali workshop, the silicon making workshop is used to implement the reaction of the hydrogen and the silicon tetrachloride to produce silicon, and the chlor-alkali workshop is used to implement the chlor-alkali process.

[0028] In a third aspect, a method for extracting lithium from lithium resources is provided, wherein the lithium resources contain a first type of recyclable material and a second type of recyclable material in addition to a lithium compound, the reactant formed by the lithium compound after a chlorination reaction in a chlorination furnace is lithium chloride, the reactant formed by the first type of recyclable material after the chlorination reaction is a first type of chloride, the reactant formed by the second type of recyclable material after the chlorination reaction is a second type of chloride, and the boiling point of the first type of chloride is greater than the boiling point of lithium chloride and greater than the boiling point of the second type of chloride; the method comprises: inputting the lithium resource into the chlorination furnace for the chlorination reaction, making the outlet temperature of the chlorination furnace a second temperature, the boiling point of the first type of chloride is greater than the second temperature ≥ the boiling point of lithium chloride and greater than the boiling point of the second type of chloride, and separating the product of the chlorination reaction between different physical states, so that the first type of chloride formed by the first type of recyclable material after the chlorination reaction exists in a tangible form and serves as a first substance to be treated, The second type of chloride formed by the second type of recyclable material after the chlorination reaction and the lithium chloride formed by the lithium compound after the chlorination reaction exist together in the form of flue gas and serve as the second material to be treated; and the second material to be treated is subjected to flue gas cooling and gas-solid separation treatment, so as to obtain a lithium target product and a second type of recyclable material target product respectively through the flue gas cooling and gas-solid separation treatment, the flue gas cooling and gas-solid separation treatment comprises at least two stages of flue gas cooling and dust removal treatment connected in series with each other, at least one stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of lithium chloride and higher than the boiling point of the second type of chloride before dust removal to obtain lithium chloride as the lithium target product, and at least one stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of the second type of chloride before dust removal to obtain the second type of chloride as the second type of recyclable material target product.

[0029] By separating the products of the chlorination reaction in different physical states, the first type of chloride formed by the first type of recyclable material after the chlorination reaction exists in the form of a tangible substance and serves as the first material to be treated, and the second type of chloride formed by the second type of recyclable material after the chlorination reaction and the lithium chloride formed by the lithium compound after the chlorination reaction exist together in the form of flue gas and serve as the second material to be treated. The method may include: a process of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace, a process of performing pre-gas-solid separation under the condition of controlling the temperature of the furnace gas to the second temperature range to obtain the second material to be treated and the pre-gas-solid separation recovered dust, and a process of configuring the slag and the pre-gas-solid separation recovered dust as the first material to be treated.

[0030] Optionally, at least the frontmost or preceding stage of the at least two stages of flue gas cooling and dust removal treatment uses a high-temperature gas filtration device, and the high-temperature gas filtration device is equipped with a filter element for physically intercepting the gas to be filtered, and the filter element is a metal filter element or a ceramic filter element.

[0031] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0032] Optionally, the first type of chlorides contains at least two chlorides; which includes: performing hydrometallurgical treatment on the first material to be treated, thereby obtaining a first type of recyclable material target product through the hydrometallurgical treatment, and the first type of recyclable material target product includes at least two recyclable material target products obtained by converting the at least two chlorides as raw materials respectively.

[0033] Optionally, the first substance to be treated is subjected to hydrometallurgical treatment to obtain a first type of recyclable target product through the hydrometallurgical treatment, comprising: configuring the first substance to be treated into a solution and then mixing it with a chemical precipitant to separate a specific chloride among the at least two chlorides from other chlorides in solid and liquid form to obtain at least two recyclable target products.

[0034] Generally speaking, water is used as a solvent, the first substance to be treated is used as a solute, and the first substance to be treated is configured as brine to serve as the solution.

[0035] Specifically, the lithium resource may be a lithium ore (the lithium ore generally comprises at least one of spodumene and lepidolite). If the lithium ore contains calcium, the first type of chloride comprises calcium chloride. If the lithium ore contains magnesium, the first type of chloride comprises magnesium chloride. If the lithium ore contains rubidium, the first type of chloride comprises rubidium chloride. If the lithium ore contains potassium, the first type of chloride comprises potassium chloride. If the lithium ore contains sodium, the first type of chloride comprises sodium chloride. If the lithium ore contains manganese, the second type of chloride comprises manganese chloride. If the lithium ore contains cesium, the second type of chloride comprises cesium chloride. If the lithium ore contains zirconium, the second type of chloride comprises zirconium chloride. If the lithium ore contains zinc, the second type of chloride comprises zinc chloride. If the lithium ore contains aluminum, the second type of chloride comprises aluminum chloride. If the lithium ore contains silicon, the second type of chloride comprises silicon tetrachloride. If the lithium ore contains iron, the second type of chloride comprises iron chloride.

[0036] Optionally, the at least two-stage flue gas cooling and dust removal treatment includes a multi-stage flue gas cooling and dust removal treatment, wherein the first stage of the multi-stage flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of ferric chloride and higher than the boiling point of aluminum chloride, and then perform dust removal to recover ferric chloride dust, and the other stage of the multi-stage flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of aluminum chloride and higher than the boiling point of silicon tetrachloride, and then perform dust removal to recover aluminum chloride dust.

[0037] Optionally, the tail gas after the multi-stage flue gas cooling and dust removal treatment is further cooled to a temperature lower than the boiling point of silicon tetrachloride and then silicon tetrachloride is obtained through gas-liquid separation.

[0038] Optionally, after separating the sodium chloride in the first category of recyclable material target products, the separated sodium chloride is used as a raw material to produce sodium hydroxide, chlorine and hydrogen through a chlor-alkali process, and then the chlorine is used for the chlorination reaction, and the hydrogen is reacted with the silicon tetrachloride to produce silicon.

[0039] Optionally, the method further comprises: dissolving lithium chloride in water to prepare a solution, and reacting the solution with sodium carbonate or sodium hydroxide after removing impurities to prepare lithium carbonate or lithium hydroxide.

[0040] Optionally, the lithium resource is waste batteries that have been pretreated, and the pretreatment includes anaerobic sublimation, pyrolysis, and cooling of the waste batteries.

[0041] Optionally, before the lithium resource is input into the chlorination furnace for the chlorination reaction, the lithium resource is first input into the second industrial furnace for heating pretreatment.

[0042] In a fourth aspect, a system for extracting lithium from lithium resources is provided, comprising: a pyrometallurgical section, a hydrometallurgical treatment section, and a flue gas cooling and gas-solid separation treatment section, wherein the hydrometallurgical treatment section and the flue gas cooling and gas-solid separation treatment section are respectively connected to the pyrometallurgical section to implement the method for extracting lithium from lithium resources of the third aspect.

[0043] Optionally, the pyrometallurgical part is deployed as a pyrometallurgical workshop, the hydrometallurgical treatment part is deployed as a hydrometallurgical workshop, and the flue gas cooling and gas-solid separation treatment part is deployed as a flue gas cooling and gas-solid separation workshop; in addition, it also includes a silicon making workshop and a chlor-alkali workshop, the silicon making workshop is used to implement the reaction of the hydrogen and the silicon tetrachloride to produce silicon, and the chlor-alkali workshop is used to implement the chlor-alkali process.

[0044] The method and system for extracting lithium from lithium resources provided by the present disclosure can fully and effectively separate and recover the valuable elements in lithium resources. In addition, the method and system for extracting lithium from lithium resources provided by the present disclosure help to simplify the process flow compared with the traditional hydrometallurgical method.

[0045] The present disclosure is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages of the present disclosure will be partially given in the following description, partially become apparent from the following description, or be understood through practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The drawings constituting a part of the present disclosure are used to assist in the understanding of the present application. The contents provided in the drawings and the related descriptions in the present specification may be used to explain the present disclosure but shall not constitute improper limitations.

[0047] Figure 1 This is a process flow chart of a method for extracting lithium from lithium resources according to Embodiment 1 of the present disclosure.

[0048] Figure 2 This is a process flow chart of a method for extracting lithium from lithium resources according to the second embodiment of the present disclosure.

[0049] Figure 3 This is a schematic diagram of the structure of a chlorination furnace according to the first embodiment of the present disclosure.

[0050] Figure 4 This is a schematic diagram of the structure of a chlorination furnace according to the second embodiment of the present disclosure.

[0051] Figure 5 for Figure 4 Top view of the .

[0052] Figure 1-Figure 2In the figure, each label consists of the letter "P" and the number after the letter "P". The letter "P" is the abbreviation of "Process", which means "process". Therefore, each label represents the mark of a process in the corresponding process flow, such as "P11" means "process 1". DETAILED DESCRIPTION

[0053] The present disclosure is described clearly and completely below in conjunction with the accompanying drawings. A person of ordinary skill in the art will be able to implement the present disclosure based on these descriptions.

[0054] Before describing the present disclosure in conjunction with the accompanying drawings, it should be particularly pointed out that the technical solutions and technical features provided in each part, including the following description, can be combined with each other if there is no conflict. In addition, where possible, these technical solutions, technical features and related combinations can be assigned specific technical themes and protected by relevant patents.

[0055] The present disclosure involved in the following description is generally only a part of the embodiments rather than all the embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of patent protection.

[0056] About the terms and units in this specification: The terms "include", "comprises", "have" and any variations thereof in this specification and the corresponding claims and related parts are intended to cover non-exclusive inclusions. Other related terms and units can be reasonably interpreted based on the relevant content of this specification.

[0057] Figure 1 FIG. 1 is a process flow chart of a method for extracting lithium from lithium resources according to Embodiment 1 of the present disclosure. Figure 1 As shown, a method for extracting lithium from lithium resources, wherein the lithium resources contain a first type of recyclable substance and a second type of recyclable substance in addition to lithium compounds, the reactant formed by the lithium compound after a chlorination reaction in a chlorination furnace is lithium chloride, the reactant formed by the first type of recyclable substance after the chlorination reaction is a first type of chloride, the reactant formed by the second type of recyclable substance after the chlorination reaction is a second type of chloride, and the boiling point of the first type of chloride is greater than the boiling point of lithium chloride and the boiling point of the second type of chloride.

[0058] The method includes:

[0059] 1) The lithium resource is input into the chlorination furnace for the chlorination reaction P11 (the chlorination reaction temperature is usually controlled to be 800°C-1400°C), so that the outlet temperature of the chlorination furnace is a first temperature, the boiling points of the lithium chloride and the first type of chloride are both greater than the first temperature, and the boiling points of the second type of chloride are both less than the first temperature, and the products of the chlorination reaction P11 are separated into different physical states, so that the lithium chloride formed by the lithium compound after the chlorination reaction and the first type of chloride formed by the first type of recyclable material after the chlorination reaction exist in the form of tangible substances and serve as the first substance to be treated, and the second type of chloride formed by the second type of recyclable material after the chlorination reaction exists in the form of flue gas and serves as the second substance to be treated.

[0060] 2) performing hydrometallurgical treatment on the first substance to be treated, thereby obtaining a lithium target product and a first type of recyclable substance target product respectively through the hydrometallurgical treatment, wherein the lithium target product is obtained by converting lithium chloride formed by the pyrometallurgical refining of the lithium compound as a raw material, and the first type of recyclable substance target product is obtained by converting the first type of chloride formed by the pyrometallurgical refining of the first type of recyclable substance as a raw material.

[0061] 3) performing flue gas cooling and gas-solid separation treatment on the second material to be treated, thereby obtaining a second type of recyclable material target product from the solid obtained by the flue gas cooling and gas-solid separation treatment, wherein the second type of recyclable material target product is obtained by converting the second type of chloride formed after the second type of recyclable material is smelted by the pyrometallurgical method as a raw material.

[0062] The above-mentioned “conversion” should be understood broadly, including both chemical conversion and physical conversion. The above-mentioned “chlorination furnace outlet temperature” obviously refers to the chlorination furnace gas outlet temperature.

[0063] Among them, the product of the chlorination reaction P11 is separated into different physical states, so that the lithium chloride formed by the lithium compound after the chlorination reaction and the first type of chloride formed by the first type of recyclable substance after the chlorination reaction exist in the form of tangible substances and serve as the first substance to be treated, and the second type of chloride formed by the second type of recyclable substance after the chlorination reaction exists in the form of flue gas and serves as the second substance to be treated. It can include: a process of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace, a process of performing pre-gas-solid separation P12 while controlling the temperature of the furnace gas to the first temperature range to obtain the second substance to be treated and the pre-gas-solid separation recovered dust, and a process of configuring the slag and the pre-gas-solid separation recovered dust as the first substance to be treated.

[0064] The chlorination furnace itself can realize the basic function of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace. At the same time, the outlet temperature of the chlorination furnace can also be controlled by adjusting the structural design of the chlorination furnace and the operating process parameters of the chlorination furnace.

[0065] The process of performing pre-gas-solid separation P12 to obtain the second substance to be treated and pre-gas-solid separation to recover dust while controlling the furnace gas temperature to the first temperature range can be achieved through conventional technologies in the field of industrial kiln furnace gas temperature control and dust removal and purification.

[0066] The purpose of the pre-gas-solid separation P12 is to separate and recover the dust entrained in the furnace gas, so as to separate the solid lithium chloride and / or the first type of chloride mixed in the gaseous second substance to be treated from the gaseous second substance to be treated.

[0067] Among them, the process of performing pre-gas-solid separation P12 to obtain the second substance to be treated and the pre-gas-solid separation to recover dust while controlling the temperature of the furnace gas to the range of the first temperature may include: after at least two stages of furnace gas cooling and dust removal treatment in series, the flue gas output by the last stage of furnace gas cooling and dust removal treatment is used as the second substance to be treated and the dust obtained by each stage of furnace gas cooling and dust removal treatment is used as the pre-gas-solid separation to recover dust, and each stage of furnace gas cooling and dust removal treatment in the at least two stages of furnace gas cooling and dust removal treatment includes the operation of cooling the furnace gas to be dusted to a set range and then performing dust removal.

[0068] By connecting at least two stages of furnace gas cooling and dust removal in series, the gas-solid separation efficiency can be improved. Since each stage of furnace gas cooling and dust removal can cool the furnace gas, it is helpful to use high-efficiency dust removal equipment in the latter furnace gas cooling and dust removal treatment in the at least two stages of furnace gas cooling and dust removal treatment, and avoid subsequent large-scale cooling.

[0069] The above-mentioned furnace gas cooling and dust removal treatment can specifically be performed by first cooling the furnace gas through a cooler and then removing dust from the furnace gas through a dust collector. Therefore, at least one cooler and at least one dust collector can be used for each level of furnace gas cooling and dust removal treatment.

[0070] Optionally, at least the last or rearmost stage of the at least two stages of furnace gas cooling and dust removal treatment uses a high-temperature gas filtering device, and the high-temperature gas filtering device is equipped with a filter element for physically intercepting the gas to be filtered, and the filter element is a metal filter element or a ceramic filter element.

[0071] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0072] Among them, the second material to be treated is subjected to flue gas cooling and gas-solid separation treatment, so as to obtain the second type of recyclable material target product from the solid obtained by the flue gas cooling and gas-solid separation treatment, which may include: through at least two stages of flue gas cooling and dust removal treatment P13 connected in series, the dust obtained by each stage of flue gas cooling and dust removal treatment P13 is separately used as a target product among the second type of recyclable material target products, and each stage of flue gas cooling and dust removal treatment P13 in the at least two stages of flue gas cooling and dust removal treatment P13 includes the operation of cooling the flue gas to be dusted to a set range and then performing dust removal.

[0073] The above-mentioned flue gas cooling and dust removal treatment P13 can specifically cool the flue gas by a cooler first, and then remove dust from the flue gas by a dust collector. Therefore, at least one cooler and at least one dust collector can be used for each level of flue gas cooling and dust removal treatment P13.

[0074] Optionally, at least the frontmost or preceding stage of the at least two stages of flue gas cooling and dust removal treatment P13 adopts a high-temperature gas filtration device, in which a filter element for physically intercepting the gas to be filtered is installed, and the filter element is a metal filter element or a ceramic filter element.

[0075] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0076] Among them, the hydrometallurgical treatment of the first substance to be treated, so as to obtain a lithium target product and a first type of recyclable substance target product respectively through the hydrometallurgical treatment, may include: configuring the first substance to be treated into a solution and then mixing it with a chemical precipitant so that the lithium compound and one of the first type of recyclable substances selectively react with the chemical precipitant and precipitate in the form of a precipitate, and then obtaining the lithium target product and the first type of recyclable substance target product respectively through solid-liquid separation.

[0077] Generally speaking, water is used as a solvent, the first substance to be treated is used as a solute, and the first substance to be treated is configured as brine to serve as the solution.

[0078] The brine here often has a significant difference in composition from the brine (such as salt lake brine) that can be used for lithium extraction in nature. In particular, since the brine in the present disclosure is artificially prepared, the concentration of solutes therein can be higher than that of brine that can be used for lithium extraction in nature, and therefore, the hydrometallurgical process in the present disclosure can be shorter, more efficient and / or less costly than the hydrometallurgical process mentioned in the background art.

[0079] In Example 1, the lithium resource is lithium ore, specifically lithium mica (concentrate, granular material), which contains lithium, calcium, magnesium, cesium, rubidium, potassium, sodium, manganese, aluminum, silicon and iron.

[0080] Before the lithium mica enters the chlorination furnace, it is generally necessary to heat the lithium mica to remove organic matter and defluorination in the lithium mica, and to loosen the structure of the lithium mica (i.e., similar to the roasting of spodumene in the existing hydrometallurgical method to convert spodumene from α crystal form to β crystal form). In addition, before the lithium mica enters the chlorination furnace, it can also be purified and / or further crushed. In short, lithium ore smelting pretreatment is a conventional technology, and generally speaking, the heating pretreatment can be implemented using a roasting kiln.

[0081] Here, the first temperature is specifically set to be greater than the boiling point of ferric chloride and less than the boiling point of lithium chloride. At this time, the first type of chlorides will include: magnesium chloride, calcium chloride, cesium chloride, rubidium chloride, potassium chloride, sodium chloride, manganese chloride; the second type of chlorides will include: aluminum chloride, silicon tetrachloride, ferric chloride.

[0082] More specifically, the first temperature may be selected to be 350°C-700°C, more preferably 350°C-600°C, and even more preferably 350°C-450°C.

[0083] At this time, the first stage of the at least two-stage flue gas cooling and dust removal treatment P13 can be used to cool the flue gas to be dusted to a temperature lower than the boiling point of ferric chloride and higher than the boiling point of aluminum chloride (for example, the flue gas to be dusted can be cooled to 200°C-300°C) and then perform dust removal to recover ferric chloride dust, and the other stage of the at least two-stage flue gas cooling and dust removal treatment P13 can be used to cool the flue gas to be dusted to a temperature lower than the boiling point of aluminum chloride and higher than the boiling point of silicon tetrachloride (for example, the flue gas to be dusted can be cooled to 80°C-150°C) and then perform dust removal to recover aluminum chloride dust.

[0084] In addition, the tail gas after the at least two-stage flue gas cooling and dust removal treatment P13 can be further cooled to a temperature lower than the boiling point of silicon tetrachloride and then separated by gas-liquid P14 to obtain silicon tetrachloride.

[0085] When the brine is subjected to hydrometallurgical treatment, an alkali (such as sodium hydroxide) can be first added to the brine to precipitate magnesium chloride, calcium chloride, etc. in the form of hydroxide precipitation. After solid-liquid separation, sodium carbonate can be added to the brine to react lithium chloride with sodium carbonate to form lithium carbonate precipitation (lithium precipitation). After solid-liquid separation again, the brine is mainly sodium chloride, and at this time, sodium chloride can be separated and recovered by concentrated crystallization.

[0086] Thereafter, the separated sodium chloride can be used as a raw material to produce sodium hydroxide, chlorine and hydrogen through the chlor-alkali process P15, and then the chlorine is used in the chlorination reaction P11, and the hydrogen is reacted with the silicon tetrachloride to produce silicon. Among them, the chlor-alkali process P15 and the reaction of hydrogen with silicon tetrachloride to produce silicon (applied in the field of polysilicon production) are both mature technologies at present.

[0087] The system for extracting lithium from lithium resources used in the method for extracting lithium from lithium resources in Example 1 includes: a pyrometallurgical smelting part, a hydrometallurgical treatment part and a flue gas cooling and gas-solid separation treatment part, and the hydrometallurgical treatment part and the flue gas cooling and gas-solid separation treatment part are respectively connected to the pyrometallurgical part to implement the method for extracting lithium from lithium resources in Example 1.

[0088] Among them, the pyrometallurgical part is deployed as a pyrometallurgical workshop, the hydrometallurgical treatment part is deployed as a hydrometallurgical workshop, and the flue gas cooling and gas-solid separation treatment part is deployed as a flue gas cooling and gas-solid separation workshop; in addition, the above-mentioned system also includes a silicon making workshop and a chlor-alkali workshop, the silicon making workshop is used to implement the reaction of the hydrogen and the silicon tetrachloride to produce silicon, and the chlor-alkali workshop is used to implement the chlor-alkali process.

[0089] In summary, the method and system for extracting lithium from lithium resources provided in the first embodiment of the present disclosure can fully and effectively separate and recover the valuable elements in the lithium resources. In addition, the method and system for extracting lithium from lithium resources provided in the first embodiment of the present disclosure help to simplify the process compared with the traditional hydrometallurgical method.

[0090] Figure 2 FIG. 2 is a process flow chart of a method for extracting lithium from lithium resources according to the second embodiment of the present disclosure. Figure 2 As shown, a method for extracting lithium from lithium resources, wherein the lithium resources contain a first type of recyclable substance and a second type of recyclable substance in addition to lithium compounds, the reactant formed by the lithium compound after a chlorination reaction in a chlorination furnace is lithium chloride, the reactant formed by the first type of recyclable substance after the chlorination reaction is a first type of chloride, the reactant formed by the second type of recyclable substance after the chlorination reaction is a second type of chloride, and the boiling point of the first type of chloride is greater than the boiling point of lithium chloride and the boiling point of the second type of chloride.

[0091] The method includes:

[0092] 1) The lithium resource is input into the chlorination furnace for the chlorination reaction P21, so that the outlet temperature of the chlorination furnace (the "outlet temperature of the chlorination furnace" should obviously refer to the outlet temperature of the chlorination furnace gas) is a second temperature, the boiling point of the first type of chloride> the second temperature ≥ the boiling point of lithium chloride> the boiling point of the second type of chloride, and the product of the chlorination reaction P21 is separated into different physical states, so that the first type of chloride formed by the first type of recyclable material after the chlorination reaction P21 exists in the form of a tangible substance and serves as the first substance to be processed, the second type of chloride formed by the second type of recyclable material after the chlorination reaction and the lithium chloride formed by the lithium compound after the chlorination reaction P21 exist in the form of flue gas and serve as the second substance to be processed.

[0093] 2) performing flue gas cooling and gas-solid separation treatment on the second material to be treated, thereby obtaining a lithium target product and a second type of recyclable material target product respectively through the flue gas cooling and gas-solid separation treatment, the flue gas cooling and gas-solid separation treatment comprises at least two stages of flue gas cooling and dust removal treatment P23 connected in series, at least one stage of the at least two stages of flue gas cooling and dust removal treatment P23 is used to cool the flue gas to be dusted to a temperature lower than the boiling point of lithium chloride and higher than the boiling point of the second type of chlorides before dust removal to obtain lithium chloride as the lithium target product, at least one stage of the at least two stages of flue gas cooling and dust removal treatment P23 is used to cool the flue gas to be dusted to a temperature lower than the boiling point of the second type of chlorides before dust removal to obtain the second type of chlorides as the second type of recyclable material target product.

[0094] By separating the products of the chlorination reaction P21 in different physical states, the first type of chloride formed by the first type of recyclable substance after the chlorination reaction P21 exists in a tangible form and serves as the first substance to be treated, the second type of chloride formed by the second type of recyclable substance after the chlorination reaction P21 and the lithium chloride formed by the lithium compound after the chlorination reaction P21 exist in the form of flue gas and serve as the second substance to be treated, comprising: a process of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace, a process of performing pre-gas-solid separation P22 while controlling the temperature of the furnace gas to the second temperature range to obtain the second substance to be treated and the pre-gas-solid separation recovered dust, and a process of configuring the slag and the pre-gas-solid separation recovered dust as the first substance to be treated.

[0095] The chlorination furnace itself can realize the basic function of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace. At the same time, the outlet temperature of the chlorination furnace can also be controlled by adjusting the structural design of the chlorination furnace and the operating process parameters of the chlorination furnace.

[0096] The process of performing pre-gas-solid separation P22 to obtain the second substance to be treated and pre-gas-solid separation to recover dust while controlling the furnace gas temperature to the second temperature range can be achieved through conventional technologies in the field of industrial kiln furnace gas temperature control and dust removal and purification.

[0097] The purpose of the pre-gas-solid separation P22 is to separate and recover the dust entrained in the furnace gas, so as to separate the solid first type chloride mixed in the gaseous second substance to be treated from the gaseous second substance to be treated.

[0098] Since the second temperature here is significantly higher than the first temperature mentioned above, the pre-gas-solid separation P22 can be achieved by using dust removal equipment such as gravity dust collector and cyclone dust collector that can withstand higher temperatures.

[0099] The above-mentioned flue gas cooling and dust removal treatment P23 can specifically cool the flue gas by a cooler first, and then remove dust from the flue gas by a dust collector. Therefore, at least one cooler and at least one dust collector can be used for each level of flue gas cooling and dust removal treatment P23.

[0100] Optionally, at least the first or the front stage of the at least two stages of flue gas cooling and dust removal treatment P23 uses a high-temperature gas filter device, and the high-temperature gas filter device is equipped with a filter element for physically intercepting the gas to be filtered, and the filter element is a metal filter element or a ceramic filter element.

[0101] Optionally, the filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

[0102] In Example 2, the lithium resource is lithium ore, specifically lithium mica (concentrate, granular material), which contains lithium, calcium, magnesium, cesium, rubidium, potassium, sodium, manganese, aluminum, silicon and iron.

[0103] Before the lithium mica enters the chlorination furnace, it is generally necessary to heat the lithium mica to remove organic matter and defluorination in the lithium mica, and to loosen the structure of the lithium mica (i.e., similar to the roasting of spodumene in the existing hydrometallurgical method to convert spodumene from α crystal form to β crystal form). In addition, before the lithium mica enters the chlorination furnace, it can also be purified and / or further crushed. In short, lithium ore smelting pretreatment is a conventional technology, and generally speaking, the heating pretreatment can be implemented using a roasting kiln.

[0104] Here, the second temperature is specifically set to be greater than the boiling point of lithium chloride and less than the boiling point of rubidium chloride (the boiling point of rubidium chloride is slightly higher than that of lithium chloride). At this time, the first type of chlorides will include: magnesium chloride, calcium chloride, rubidium chloride, potassium chloride, sodium chloride; the second type of chlorides will include: aluminum chloride, silicon tetrachloride, ferric chloride, cesium chloride, manganese chloride.

[0105] Note: Since the chlorination reaction in the present disclosure actually generates a mixture of multiple chlorides, the boiling point of lithium chloride is lower than that of pure lithium chloride. Therefore, the above "boiling point" should be reasonably understood as the actual boiling point of the corresponding chloride.

[0106] At this time, the at least two-stage flue gas cooling and dust removal treatment P23 includes a multi-stage flue gas cooling and dust removal treatment P23, in which the first stage of the flue gas cooling and dust removal treatment P23 can be used to cool the flue gas to be dusted to a temperature lower than the boiling point of ferric chloride and higher than the boiling point of aluminum chloride (for example, the flue gas to be dusted can be cooled to 200°C-300°C) and then perform dust removal to recover ferric chloride dust, and the other stage of the flue gas cooling and dust removal treatment P13 in the at least two-stage flue gas cooling and dust removal treatment P23 can be used to cool the flue gas to be dusted to a temperature lower than the boiling point of aluminum chloride and higher than the boiling point of silicon tetrachloride (for example, the flue gas to be dusted can be cooled to 80°C-150°C) and then perform dust removal to recover aluminum chloride dust.

[0107] In addition, the tail gas after the multi-stage flue gas cooling and dust removal treatment P23 can be further cooled to a temperature lower than the boiling point of silicon tetrachloride and then separated by gas-liquid separation P24 to obtain silicon tetrachloride.

[0108] The first substance to be treated is subjected to hydrometallurgical treatment to obtain a first type of recyclable target product through the hydrometallurgical treatment, comprising: configuring the first substance to be treated into a solution and then mixing it with a chemical precipitant to separate a specific chloride among the at least two chlorides from other chlorides in solid and liquid form to obtain at least two recyclable target products.

[0109] Typically, water is used as a solvent, the first substance to be treated is used as a solute, and the first substance to be treated is configured as brine to serve as the solution.

[0110] When the brine is subjected to hydrometallurgical treatment, an alkali (such as sodium hydroxide) can be first added to the brine to precipitate magnesium chloride, calcium chloride, etc. in the form of hydroxide precipitation. After solid-liquid separation, sodium carbonate can be added to the brine to react lithium chloride with sodium carbonate to form lithium carbonate precipitation (lithium precipitation). After solid-liquid separation again, the brine is mainly sodium chloride, and at this time, sodium chloride can be separated and recovered by concentrated crystallization.

[0111] Afterwards, the separated sodium chloride can be used as a raw material to produce sodium hydroxide, chlorine and hydrogen through the chlor-alkali process P25, and then the chlorine is used in the chlorination reaction P21, and the hydrogen is reacted with the silicon tetrachloride to produce silicon. Among them, the chlor-alkali process P25 and the reaction of hydrogen with silicon tetrachloride to produce silicon (applied in the field of polysilicon production) are both mature technologies at present.

[0112] Finally, lithium chloride can be dissolved in water to prepare a solution, which can then be reacted with sodium carbonate or sodium hydroxide to prepare lithium carbonate or lithium hydroxide after impurities are removed.

[0113] The system for extracting lithium from lithium resources used in the method for extracting lithium from lithium resources of Example 2 includes: a pyrometallurgical section, a hydrometallurgical treatment section, and a flue gas cooling and gas-solid separation treatment section. The hydrometallurgical treatment section and the flue gas cooling and gas-solid separation treatment section are respectively connected to the pyrometallurgical section to implement the method for extracting lithium from lithium resources of Example 2.

[0114] Among them, the pyrometallurgical part is deployed as a pyrometallurgical workshop, the hydrometallurgical treatment part is deployed as a hydrometallurgical workshop, and the flue gas cooling and gas-solid separation treatment part is deployed as a flue gas cooling and gas-solid separation workshop; in addition, the above-mentioned system also includes a silicon making workshop and a chlor-alkali workshop, the silicon making workshop is used to implement the reaction of the hydrogen and the silicon tetrachloride to produce silicon, and the chlor-alkali workshop is used to implement the chlor-alkali process.

[0115] In summary, the method and system for extracting lithium from lithium resources provided in the second embodiment of the present disclosure can fully and effectively separate and recover the valuable elements in the lithium resources. In addition, the method and system for extracting lithium from lithium resources provided in the second embodiment of the present disclosure help to simplify the process flow compared with the traditional hydrometallurgical method. Since lithium chloride is separated and recovered by flue gas cooling and dust removal treatment P23, it is easier to enrich.

[0116] Figure 3 A schematic diagram of the structure of a chlorination furnace in Embodiment 1 of the present disclosure. The chlorination furnace can be used in the method for extracting lithium from lithium resources provided in Embodiment 1 or the method for extracting lithium from lithium resources provided in Embodiment 2. Figure 3 As shown, the chlorination furnace includes: an upper fluidized chlorination zone, wherein the upper fluidized chlorination zone is used to cause the raw materials added into the upper fluidized chlorination zone to undergo a first chlorination reaction with a chlorinating agent; a lower molten salt chlorination zone, wherein the lower molten salt chlorination zone is used to cause part of the materials in the upper fluidized chlorination zone to settle into the lower molten salt chlorination zone to form molten salt and undergo a second chlorination reaction with the chlorinating agent; and a chloride flue gas discharge zone, wherein the chloride flue gas discharge zone is connected to the upper space of the lower molten salt chlorination zone and the upper fluidized chlorination zone, and is used to discharge the chloride flue gas generated by the chlorination furnace out of the chlorination furnace.

[0117] More specifically, the upper fluidized chlorination zone is composed of a reaction tower 1, which has a vertical reaction tower body; the lower molten salt chlorination zone is composed of a molten salt pool 3 arranged at the bottom of the reaction tower 1, and the molten salt pool 3 has a horizontal molten salt pool body and the outer shell is an integral structure with the outer shell of the reaction tower 1; the chloride flue gas emission zone is composed of a vertical flue 4 arranged at the top of the molten salt pool 3 and deviated from the reaction tower 1; wherein, the interior of the molten salt pool is located above the molten salt and has a transverse flue with two ends respectively connected to the bottom of the reaction tower 1 and the bottom of the longitudinal flue 4.

[0118] Generally speaking, a feeding structure 2 is provided at the top of the upper fluidized chlorination zone, and the feeding structure 2 is used to add the raw material (lithium resource), chlorinating agent, chlorination reaction reducing agent, and combustion-supporting material, at least the raw material and the chlorinating agent, independently or mixedly, into the upper fluidized chlorination zone. Among them, the chlorinating agent is chlorine. The chlorination reaction reducing agent (which can make the chlorination reaction more effective) is usually a carbon-based reducing agent, such as coke, petroleum coke powder, etc. The combustion-supporting material is usually fuel and oxygen.

[0119] Specifically, the feeding structure 2 adopts a mixing nozzle, which can mix the raw materials, chlorinating agent, chlorination reaction reducing agent, and combustion-supporting material and spray them evenly into the upper fluid chlorination zone, which helps to increase the chlorination rate.

[0120] Generally speaking, the lower molten salt chlorination zone is provided with a chlorine gas nozzle 5 extending into the molten salt, so that the molten salt is stirred by chlorine gas to improve the heat transfer and mass transfer conditions of the molten salt. A salt discharge port 6 can be provided on the side or other suitable position of the lower molten salt chlorination zone.

[0121] In addition, a heating electrode 7 may be provided in the lower molten salt chlorination zone, and the heating electrode 7 is preferably a graphite electrode, and the number of the graphite electrodes may be three or more. Thus, the heating electrode 7 maintains an appropriate temperature of the molten pool, ensures sufficient chlorination, and avoids agglomeration due to a decrease in the molten pool temperature.

[0122] The operation process of the above-mentioned chlorination furnace is as follows (taking the method for extracting lithium from lithium resources provided in Example 1 as an example): the raw material, i.e. the above-mentioned lithium resource, is added to the upper fluidized chlorination zone to undergo a first chlorination reaction with a chlorinating agent. The raw material contains elements such as iron, aluminum, silicon, calcium, magnesium, and aluminum (in the form of corresponding oxides). During the first chlorination reaction, they react rapidly in a high-temperature floating state to generate high-boiling lithium chloride, calcium chloride, and magnesium chloride, as well as low-boiling aluminum chloride, silicon tetrachloride, and ferric chloride. Low-boiling chlorides such as silicon tetrachloride and aluminum chloride form flue gas, and high-boiling chlorides such as lithium chloride, calcium chloride, and magnesium chloride and a small portion of unreacted materials are precipitated into the molten salt pool 3 to form molten salt. Supplementary chlorine is introduced from the chlorine gas nozzle 5 to carry out a second chlorination reaction with the unreacted materials under the molten salt system to achieve complete chlorination of the lithium ore. The high-boiling chloride molten salt obtained by the first chlorination reaction and the second chlorination reaction can be discharged from the salt discharge port 6, and the low-boiling chloride flue gas is discharged from the longitudinal flue 4.

[0123] The above-mentioned chlorination furnace can convert all valuable metals in lithium ore into chloride salts, and realize the preliminary separation between chlorides with higher boiling points and chlorides with lower boiling points. In addition, it helps the chlorination furnace to more fully chlorinate the raw materials in the chlorination furnace in a shorter time.

[0124] Optionally, the inner width or inner diameter of the vertical reaction tower body is 0.5-15 meters, and the height of the vertical reaction tower body is 2.5-40 meters.

[0125] Optionally, the outer shell of the vertical reaction tower body and / or the horizontal molten salt pool body is made of refractory bricks or amorphous refractory materials.

[0126] Optionally, a water cooling structure, such as a copper water jacket, a water-cooled wall or an open water type water cooling protection device, is provided on the outer shell of the vertical reaction tower body and / or the horizontal molten salt pool body.

[0127] Optionally, the internal width or inner diameter of the horizontal molten salt pool body is greater than the internal width or inner diameter of the vertical reaction tower body by more than 0.4 meters;

[0128] Optionally, the inner surface of the vertical reaction tower body and / or the horizontal molten salt pool body is made of a high temperature resistant material that is resistant to chlorine corrosion.

[0129] In addition, an independent chlorine gas inlet 9 may be provided at the upper portion of the reaction tower 1 for introducing chlorine gas into the upper fluidized chlorination zone.

[0130] Figure 4 This is a schematic diagram of the structure of a chlorination furnace according to the second embodiment of the present disclosure. Figure 5 for Figure 4The chlorination furnace can be used in the method for extracting lithium from lithium resources provided in Example 1 or the method for extracting lithium from lithium resources provided in Example 2. Figure 4-Figure 5 As shown, the chlorination furnace includes: an upper fluidized chlorination zone, wherein the upper fluidized chlorination zone is used to cause the raw materials added to the upper fluidized chlorination zone to undergo a first chlorination reaction with a chlorinating agent; a lower molten salt chlorination zone, wherein the lower molten salt chlorination zone is used to cause part of the materials in the upper fluidized chlorination zone to settle into the lower molten salt chlorination zone to form molten salt and undergo a second chlorination reaction with the chlorinating agent; an upper chloride discharge zone, wherein the upper chloride discharge zone is connected to the upper fluidized chlorination zone and is used to discharge the chloride flue gas generated in the upper fluidized chlorination zone out of the chlorination furnace; and a lower chloride discharge zone, wherein the lower chloride discharge zone is connected to the lower molten salt chlorination zone and is used to discharge the chloride generated in the lower molten salt chlorination zone out of the chlorination furnace.

[0131] More specifically, the upper fluid chlorination zone is composed of a reaction tower 1, which has a vertical reaction tower body; the lower molten salt chlorination zone is composed of a molten salt pool 3 arranged at the bottom of the reaction tower 1, and the molten salt pool 3 has a horizontal molten salt pool body and the outer shell is an integral structure with the outer shell of the reaction tower 1; the upper chloride discharge zone is composed of a first flue 10 arranged at the top of the reaction tower 1; the lower chloride discharge zone includes a second flue 11 arranged at the top of the molten salt pool 3 and deviated from the reaction tower 1, and a salt discharge port 6 arranged on the side of the molten salt pool 3.

[0132] In an optional embodiment, the second flue 11 may include at least two exhaust structures spaced apart from each other around the reaction tower 1. The exhaust structure may include gas collecting hoods located on each exhaust port. These gas collecting hoods may be connected to an exhaust main pipe 15.

[0133] Optionally, the inner width or inner diameter of the vertical reaction tower body is 0.5-15 meters, and the height of the vertical reaction tower body is 2.5-40 meters.

[0134] Optionally, the outer shell of the vertical reaction tower body and / or the horizontal molten salt pool body is made of refractory bricks or amorphous refractory materials.

[0135] Optionally, a water cooling structure, such as a copper water jacket, a water-cooled wall or an open water type water cooling protection device, is provided on the outer shell of the vertical reaction tower body and / or the horizontal molten salt pool body.

[0136] Optionally, the internal width or inner diameter of the horizontal molten salt pool body is greater than the internal width or inner diameter of the vertical reaction tower body by more than 0.4 meters;

[0137] Optionally, the inner surface of the vertical reaction tower body and / or the horizontal molten salt pool body is made of a high temperature resistant material that is resistant to chlorine corrosion.

[0138] Generally speaking, a feeding structure 12 is provided at the upper part of the upper fluidized chlorination zone, and the feeding structure 12 is used to add at least the raw material, the chlorination reaction reducing agent, and the combustion-supporting substance to the upper fluidized chlorination zone independently or in a mixed manner. Among them, the chlorination reaction reducing agent (which can make the chlorination reaction more efficient) is usually a carbon-based reducing agent, such as coke, petroleum coke powder, etc. The combustion-supporting substance is usually fuel and oxygen.

[0139] Generally speaking, the lower part of the upper fluidized chlorination zone is provided with a chlorine gas inlet 13 and a hot gas inlet 14. Hot gas is input into the upper fluidized chlorination zone through the hot gas inlet 14, which can be used for gas velocity regulation and temperature control in the upper fluidized chlorination zone.

[0140] Generally speaking, the lower molten salt chlorination zone is provided with a chlorine gas nozzle 5 extending into the molten salt, so that the molten salt is stirred by chlorine gas to improve the heat transfer and mass transfer conditions of the molten salt. A salt discharge port 6 can be provided on the side or other suitable position of the lower molten salt chlorination zone.

[0141] In addition, a heating electrode 7 may be provided in the lower molten salt chlorination zone, and the heating electrode 7 is preferably a graphite electrode, and the number of the graphite electrodes may be three or more, and the three or more heating electrodes 7 may be evenly distributed along the circumference of the lower molten salt chlorination zone. Thus, the heating electrode 7 maintains an appropriate temperature of the molten pool, ensures sufficient chlorination, and avoids agglomeration due to a decrease in the molten pool temperature.

[0142] In addition, the lower molten salt chlorination zone may be an annular structure, and the annular structure may be formed by a protrusion arranged at the bottom of the lower molten salt chlorination zone.

[0143] The operation process of the above-mentioned chlorination furnace is as follows (taking the method for extracting lithium from lithium resources provided in Example 2 as an example): the raw material, i.e. the above-mentioned chlorination metallurgical semi-finished product, is added to the upper fluidized chlorination zone to undergo a first chlorination reaction with a chlorinating agent. The raw material contains elements such as potassium, sodium, silicon, rubidium, cesium, and aluminum (in the form of corresponding oxides). During the first chlorination reaction, they react rapidly in a high-temperature floating state to generate high-boiling lithium chloride, potassium chloride, sodium chloride, rubidium chloride, cesium chloride, and low-boiling aluminum chloride, silicon tetrachloride, etc. Low-boiling chlorides such as silicon tetrachloride and aluminum chloride form flue gas and are quickly discharged from the upper chloride discharge zone. High-boiling chlorides such as potassium chloride and a small portion of unreacted materials are precipitated into the molten salt pool 3 together to form molten salt. Supplementary chlorine is introduced from the chlorine gas nozzle 5 to carry out a second chlorination reaction with the unreacted materials in the molten salt system to achieve complete chlorination of the lithium ore. The high-boiling-point chloride molten salt obtained by the first chlorination reaction and the second chlorination reaction can be discharged from the salt discharge port 6, and the chloride flue gas overflowing from the molten salt pool (the chloride overflowing from the molten salt pool is mainly lithium chloride by controlling the temperature of the molten salt pool) is discharged from the second flue.

[0144] The above is a description of the relevant contents of the present application. A person skilled in the art will be able to implement the present application based on these descriptions. Based on the above contents of this specification, all other embodiments obtained by a person skilled in the art without making any creative work shall fall within the scope of patent protection.

Claims

1. A method for extracting lithium from lithium resources, characterized in that: The lithium resource contains a first type of recyclable material and a second type of recyclable material in addition to the lithium compound. The reactant formed by the lithium compound after the chlorination reaction in the chlorination furnace is lithium chloride. The reactant formed by the first type of recyclable material after the chlorination reaction is a first type of chloride. The reactant formed by the second type of recyclable material after the chlorination reaction is a second type of chloride. The boiling point of the first type of chloride is greater than the boiling point of lithium chloride and greater than the boiling point of the second type of chloride. It includes: Input the lithium resource into the chlorination furnace for the chlorination reaction, so that the outlet temperature of the chlorination furnace is a second temperature, the boiling point of the first type of chloride> the second temperature ≥ the boiling point of lithium chloride> the boiling point of the second type of chloride, and separate the products of the chlorination reaction into different physical states, so that the first type of chloride formed by the first type of recyclable material after the chlorination reaction exists in the form of a tangible substance and serves as the first substance to be processed, and the second type of chloride formed by the second type of recyclable material after the chlorination reaction and the lithium chloride formed by the lithium compound after the chlorination reaction exist in the form of flue gas and serve as the second substance to be processed; as well as The second material to be treated is subjected to flue gas cooling and gas-solid separation treatment, so as to obtain a lithium target product and a second type of recyclable material target product respectively through the flue gas cooling and gas-solid separation treatment, the flue gas cooling and gas-solid separation treatment comprises at least two stages of flue gas cooling and dust removal treatment connected in series, at least one stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of lithium chloride and higher than the boiling point of the second type of chlorides before dust removal to obtain lithium chloride as the lithium target product, and at least one stage of the at least two stages of flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of the second type of chlorides before dust removal to obtain the second type of chlorides as the second type of recyclable material target product.

2. The method for extracting lithium from lithium resources according to claim 1, characterized in that: By separating the products of the chlorination reaction in different physical states, the first type of chloride formed by the first type of recyclable material after the chlorination reaction exists in the form of a tangible substance and serves as the first material to be treated, and the second type of chloride formed by the second type of recyclable material after the chlorination reaction and the lithium chloride formed by the lithium compound after the chlorination reaction exist together in the form of flue gas and serve as the second material to be treated, comprising: a process of separating the slag produced by the chlorination furnace from the furnace gas produced by the chlorination furnace, a process of performing pre-gas-solid separation under the condition of controlling the temperature of the furnace gas to the second temperature range to obtain the second material to be treated and the pre-gas-solid separation recovered dust, and a process of configuring the slag and the pre-gas-solid separation recovered dust as the first material to be treated.

3. The method for extracting lithium from lithium resources according to claim 1, characterized in that: At least the frontmost or preceding stage of the at least two stages of flue gas cooling and dust removal treatment uses a high-temperature gas filtering device, in which a filter element for physically intercepting the gas to be filtered is installed, and the filter element is a metal filter element or a ceramic filter element.

4. The method for extracting lithium from lithium resources according to claim 3, characterized in that: The filter element is a metal membrane filter element; or, the filter element is a metal filter bag formed by making a metal membrane into a bag shape.

5. The method for extracting lithium from lithium resources according to claim 1, characterized in that: The first type of chlorides contains at least two chlorides; it includes: performing hydrometallurgical treatment on the first material to be treated, thereby obtaining a first type of recyclable material target product through the hydrometallurgical treatment, and the first type of recyclable material target product includes at least two recyclable material target products obtained by converting the at least two chlorides as raw materials respectively.

6. The method for extracting lithium from lithium resources according to claim 5, characterized in that: The first substance to be treated is subjected to hydrometallurgical treatment to obtain a first type of recyclable target product through the hydrometallurgical treatment, comprising: configuring the first substance to be treated into a solution and then mixing it with a chemical precipitant to separate a specific chloride among the at least two chlorides from other chlorides in solid and liquid form to obtain at least two recyclable target products.

7. The method for extracting lithium from lithium resources according to claim 6, characterized in that: With water as solvent and the first substance to be treated as solute, the first substance to be treated is configured into brine to serve as the solution.

8. The method for extracting lithium from lithium resources according to any one of claims 1 to 7, characterized in that: The lithium resource is lithium ore. If the lithium ore contains calcium, the first type of chloride contains calcium chloride. If the lithium ore contains magnesium, the first type of chloride contains magnesium chloride. If the lithium ore contains rubidium, the first type of chloride contains rubidium chloride. If the lithium ore contains potassium, the first type of chloride contains potassium chloride. If the lithium ore contains sodium, the first type of chloride contains sodium chloride. If the lithium ore contains manganese, the second type of chloride contains manganese chloride. If the lithium ore contains cesium, the second type of chloride contains cesium chloride. If the lithium ore contains zirconium, the second type of chloride contains zirconium chloride. If the lithium ore contains zinc, the second type of chloride contains zinc chloride. If the lithium ore contains aluminum, the second type of chloride contains aluminum chloride. If the lithium ore contains silicon, the second type of chloride contains silicon tetrachloride. If the lithium ore contains iron, the second type of chloride contains ferric chloride.

9. The method for extracting lithium from lithium resources according to claim 8, characterized in that: The lithium ore comprises at least one of spodumene and lepidolite.

10. The method for extracting lithium from lithium resources according to claim 9, characterized in that: The at least two-stage flue gas cooling and dust removal treatment includes a multi-stage flue gas cooling and dust removal treatment, wherein a first stage of the multi-stage flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of ferric chloride and higher than the boiling point of aluminum chloride, and then perform dust removal to recover ferric chloride dust, and another stage of the multi-stage flue gas cooling and dust removal treatment is used to cool the flue gas to be dusted to a temperature lower than the boiling point of aluminum chloride and higher than the boiling point of silicon tetrachloride, and then perform dust removal to recover aluminum chloride dust.

11. The method for extracting lithium from lithium resources according to claim 10, characterized in that: The tail gas after the multi-stage flue gas cooling and dust removal treatment is further cooled to a temperature lower than the boiling point of silicon tetrachloride and then separated into gas and liquid to obtain silicon tetrachloride.

12. The method for extracting lithium from lithium resources according to claim 11, characterized in that: After separating the sodium chloride in the first category of recyclable material target products, the separated sodium chloride is used as a raw material to produce sodium hydroxide, chlorine and hydrogen through a chlor-alkali process, and then the chlorine is used for the chlorination reaction, and the hydrogen is reacted with the silicon tetrachloride to produce silicon.

13. The method for extracting lithium from lithium resources according to claim 1, characterized in that: Also includes: Lithium chloride is dissolved in water to prepare a solution, which is then reacted with sodium carbonate or sodium hydroxide after impurities are removed to prepare lithium carbonate or lithium hydroxide.

14. The method for extracting lithium from lithium resources according to any one of claims 1 to 7, characterized in that: The lithium resource is waste batteries that have been pre-treated, and the pre-treatment includes anaerobic sublimation, pyrolysis, and cooling processes of the waste batteries.

15. The method for extracting lithium from lithium resources according to claim 1, characterized in that: Before the lithium resource is input into the chlorination furnace for the chlorination reaction, the lithium resource is first input into the second industrial furnace for heating pretreatment.

16. A system for extracting lithium from lithium resources, characterized in that: include: A pyrometallurgical section, a hydrometallurgical treatment section and a flue gas cooling and gas-solid separation treatment section, wherein the hydrometallurgical treatment section and the flue gas cooling and gas-solid separation treatment section are respectively connected to the pyrometallurgical section so as to implement the method for extracting lithium from lithium resources as described in any one of claims 1 to 15.

17. The system for extracting lithium from lithium resources according to claim 16, characterized in that: The pyrometallurgical part is deployed as a pyrometallurgical workshop, the hydrometallurgical treatment part is deployed as a hydrometallurgical workshop, and the flue gas cooling and gas-solid separation treatment part is deployed as a flue gas cooling and gas-solid separation workshop; in addition, it also includes a silicon making workshop and a chlor-alkali workshop. The silicon making workshop is used to react the hydrogen with the silicon tetrachloride to produce silicon, and the chlor-alkali workshop is used to implement the chlor-alkali process.

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