Brown fused alumina smelting smoke dust recovery method

Abstract

The invention provides a brown aluminum oxide smelting smoke dust recovery method which comprises the following steps: monitoring tail gas emission characteristics of a brown aluminum oxide smelting electric arc furnace, and adjusting tail gas smoke dust collection parameters of the electric arc furnace; the collected flue gas is pretreated into an alkaline solution, and the alkaline solution is subjected to acidification treatment and reaction until precipitates are generated in the solution; the solution is filtered and separated into precipitates and filtrate, the precipitates are treated to obtain gallium-containing minerals, and metal gallium is obtained through electrolytic extraction; the electric arc furnace is subjected to dynamic tail gas emission detection, tail gas smoke dust can be efficiently and comprehensively collected, smoke dust leakage in the tail gas collection process is reduced to the maximum extent, the smoke dust is dissolved and reacted in the solution environment, the acid-base characteristic of the solution is adjusted, and the potassium fertilizer is obtained. Gallium element precipitation is achieved, the gallium metal refining efficiency and purity are improved, a potash fertilizer is additionally formed, and the variety and yield of products for smoke dust recycling are improved.

Description

Technical Field

[0001] The invention relates to the technical field of corundum smelting resource recovery, in particular to a method for recovering brown corundum smelting smoke. Background Art

[0002] Brown corundum smelting usually includes two processes: calcination and smelting. Specifically, bauxite is first placed in a rotary kiln for high-temperature calcination to dehydrate and decompose the bauxite to obtain bauxite clinker; the bauxite clinker is then placed in an electric arc furnace for high-temperature smelting to obtain finished corundum products. The high-temperature tail gas generated by the electric arc furnace during the high-temperature smelting process contains a large amount of smoke dust. The main components of these smoke dusts include compound particles containing gallium elements. If the high-temperature tail gas is directly discharged into the external environment without any treatment, it will not only cause environmental pollution, but also cause waste of gallium resources. Gallium, as a widely used metal, is a by-product of bauxite smelting. How to efficiently recover the smoke dust generated by corundum smelting and refine and purify the gallium resources in the smoke dust is of great significance to increasing the production and reserves of gallium metal. Summary of the invention

[0003] In view of the defects of the prior art, the present invention provides a method for recovering brown corundum smelting smoke, which monitors the exhaust emission characteristics of the brown corundum smelting arc furnace and adjusts the exhaust smoke collection parameters of the arc furnace; pre-treats the collected smoke into an alkaline solution, and performs acidification and reaction on the alkaline solution until a precipitate is generated in the solution; filters the solution to separate it into a precipitate and a filtrate, treats the precipitate to obtain a gallium-containing mineral, and then obtains metallic gallium through electrolytic extraction; treats the filtrate to obtain a potassium salt solution, and then obtains potash fertilizer through crystallization extraction; and through dynamic exhaust emission detection of the arc furnace, the exhaust smoke can be efficiently and comprehensively collected, and the smoke leakage in the exhaust gas collection process can be minimized; by dissolving and reacting the smoke in a solution environment and adjusting the acid-base characteristics of the solution, the gallium element is precipitated, the gallium metal extraction efficiency and purity are improved, and potash fertilizer is additionally formed, thereby increasing the variety and output of smoke recovery products.

[0004] The present invention provides a method for recovering brown corundum smelting dust, comprising the following steps:

[0005] Step S1, monitoring the tail gas of the brown corundum smelting arc furnace to obtain tail gas emission characteristics; and adjusting the tail gas and smoke collection parameters of the arc furnace according to the tail gas emission characteristics;

[0006] Step S2, pre-treating the collected smoke in an alkaline environment to obtain an alkaline solution; acidifying and reacting the alkaline solution until a precipitate is generated in the solution;

[0007] Step S3, filtering the solution to separate into a precipitate and a filtrate, performing leaching and neutralization treatment on the precipitate to obtain a gallium-containing mineral; and performing electrolytic extraction on the gallium-containing mineral to obtain metallic gallium;

[0008] Step S4, neutralizing and reacting the filtrate to obtain a potassium salt solution; and crystallizing and extracting the potassium salt solution to obtain potash fertilizer.

[0009] In one embodiment disclosed in the present application, in step S1, tail gas monitoring is performed on a brown corundum smelting arc furnace to obtain tail gas emission characteristics, including:

[0010] Detect and analyze the smelting temperature data inside the arc furnace for smelting brown corundum to determine the smelting progress inside the arc furnace; wherein the smelting temperature data includes the smelting temperature spatial distribution data and the smelting temperature time domain variation data inside the arc furnace;

[0011] According to the smelting progress, the frequency of tail gas monitoring of the electric arc furnace is adjusted, and the tail gas emission characteristics of the electric arc furnace are obtained; wherein the tail gas emission characteristics include the tail gas temperature and tail gas particle concentration emitted by the electric arc furnace.

[0012] In one embodiment disclosed in the present application, in the step S1, adjusting the tail gas and fume collection parameters of the electric arc furnace according to the tail gas emission characteristics includes:

[0013] According to the tail gas temperature and tail gas particle concentration of the electric arc furnace, the pressure change trend of the tail gas discharged from the electric arc furnace is predicted;

[0014] According to the pressure change trend of the exhaust gas emitted by the electric arc furnace, it is judged whether the exhaust gas emitted by the electric arc furnace is in an abnormal pressure state; when it is in an abnormal pressure state, the negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are adjusted; when it is not in an abnormal pressure state, the current negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are kept unchanged.

[0015] In one embodiment disclosed in the present application, in step S2, the collected smoke is pretreated in an alkaline environment to obtain an alkaline solution, comprising:

[0016] The collected smoke is cooled and allowed to stand, then dissolved in a KOH solution, and the KOH solution is heated to obtain an alkaline solution; wherein the heating temperature of the KOH solution is not less than 120°C.

[0017] In one embodiment disclosed in the present application, in the step S2, the alkaline solution is subjected to acidification and reaction until a precipitate is generated in the solution, comprising:

[0018] During the heat preservation process of the alkaline solution, carbon dioxide is input to react so that the pH value of the alkaline solution drops to less than or equal to 8, until a precipitate is generated in the solution.

[0019] In one embodiment disclosed in the present application, in the step S2, the temperature of the heat preservation treatment is 80-90°C, and the flow rate of the carbon dioxide input into the alkaline solution is at least 1 L / min.

[0020] In one embodiment disclosed in the present application, in step S3, the solution is filtered and separated into a precipitate and a filtrate, and the precipitate is subjected to leaching and neutralization treatment to obtain a gallium-containing mineral, including:

[0021] The solution is centrifuged and filtered to obtain a precipitate and a filtrate; wherein the centrifugal rotation speed of the centrifugal precipitation is 300-500 r / min;

[0022] The precipitate is immersed in a sulfuric acid solution for dissolution treatment to obtain a leaching solution; the leaching solution is subjected to a pH neutralization treatment so that the pH value of the leaching solution becomes 7-8; the neutralized leaching solution is filtered to obtain a gallium-containing mineral.

[0023] In one embodiment disclosed in the present application, in step S3, electrolytic extraction is performed on the gallium-containing mineral to obtain metallic gallium, including:

[0024] After the gallium-containing mineral is dissolved in an alkaline solution, the alkaline solution is subjected to electrolytic extraction to obtain a metallic gallium extract, and then the metallic gallium extract is subjected to refining and purification to obtain metallic gallium.

[0025] In one embodiment disclosed in the present application, in the step S4, the filtrate is subjected to a neutralization treatment and a reaction treatment to obtain a potassium salt solution, comprising:

[0026] Ammonia water is added to the filtrate for neutralization treatment until the pH value of the filtrate becomes 7-8; the neutralized filtrate is heated for reaction treatment to promote the potassium ions in the filtrate to react with ammonium ions to obtain a potassium salt solution.

[0027] In one embodiment disclosed in the present application, in the step S4, the potassium salt solution is subjected to crystallization extraction to obtain potassium fertilizer, comprising:

[0028] The potassium salt solution is subjected to thermal evaporation treatment to obtain potassium salt crude material; the potassium salt crude material is subjected to secondary dissolution and crystallization purification treatment to obtain potash fertilizer.

[0029] Compared with the prior art, the brown corundum smelting smoke recovery method monitors the exhaust emission characteristics of the brown corundum smelting arc furnace, adjusts the exhaust smoke collection parameters of the arc furnace; pre-treats the collected smoke into an alkaline solution, and acidifies and reacts the alkaline solution until a precipitate is generated in the solution; filters the solution to separate it into a precipitate and a filtrate, treats the precipitate to obtain a gallium-containing mineral, and then extracts metallic gallium through electrolysis; treats the filtrate to obtain a potassium salt solution, and then extracts potash fertilizer through crystallization; and through dynamic exhaust emission detection of the arc furnace, the exhaust smoke can be efficiently and comprehensively collected, and smoke leakage during the exhaust gas collection process can be minimized; by dissolving and reacting the smoke in a solution environment, and by adjusting the acid-base characteristics of the solution, the gallium element is precipitated, the gallium metal extraction efficiency and purity are improved, and potash fertilizer is additionally formed, thereby increasing the variety and output of smoke recovery products.

[0030] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0031] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic flow chart of the method for recovering brown corundum smelting dust provided by the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1 , is a schematic diagram of a process for recovering brown corundum smelting dust provided by an embodiment of the present invention. The brown corundum smelting dust recovery method comprises:

[0036] Step S1, monitoring the tail gas of the brown corundum smelting arc furnace to obtain tail gas emission characteristics; and adjusting the tail gas and smoke collection parameters of the arc furnace according to the tail gas emission characteristics;

[0037] Step S2, pre-treating the collected smoke in an alkaline environment to obtain an alkaline solution; acidifying and reacting the alkaline solution until a precipitate is generated in the solution;

[0038] Step S3, filtering the solution to separate into a precipitate and a filtrate, performing leaching and neutralization treatment on the precipitate to obtain a gallium-containing mineral; and performing electrolytic extraction on the gallium-containing mineral to obtain metallic gallium;

[0039] Step S4, neutralizing and reacting the filtrate to obtain a potassium salt solution; and crystallizing and extracting the potassium salt solution to obtain potash fertilizer.

[0040] The beneficial effects of the above technical scheme are as follows: the brown corundum smelting smoke recovery method monitors the exhaust emission characteristics of the brown corundum smelting arc furnace, and adjusts the exhaust smoke collection parameters of the arc furnace; pre-treats the collected smoke into an alkaline solution, and acidifies and reacts the alkaline solution until a precipitate is generated in the solution; filters the solution to separate it into a precipitate and a filtrate, treats the precipitate to obtain a gallium-containing mineral, and then extracts metallic gallium through electrolysis; treats the filtrate to obtain a potassium salt solution, and then extracts potash fertilizer through crystallization; and through dynamic exhaust emission detection of the arc furnace, the exhaust smoke can be efficiently and comprehensively collected, and the smoke leakage during the exhaust gas collection process can be minimized. By dissolving and reacting the smoke in a solution environment and adjusting the acid-base characteristics of the solution, the gallium element is precipitated, the gallium metal extraction efficiency and purity are improved, and potash fertilizer is additionally formed, thereby increasing the variety and output of smoke recovery products.

[0041] Preferably, in step S1, tail gas monitoring is performed on the brown corundum smelting arc furnace to obtain tail gas emission characteristics, including:

[0042] Detect and analyze the smelting temperature data inside the arc furnace for brown corundum smelting to determine the smelting progress inside the arc furnace; the smelting temperature data includes the smelting temperature spatial distribution data inside the arc furnace and the smelting temperature time domain variation data;

[0043] According to the smelting progress, the frequency of tail gas monitoring of the electric arc furnace is adjusted, and the tail gas emission characteristics of the electric arc furnace are obtained; wherein the tail gas emission characteristics include the tail gas temperature and tail gas particle concentration emitted by the electric arc furnace.

[0044] The beneficial effects of the above technical solution are as follows: a large amount of high-temperature smoke will be generated during the smelting of brown corundum in the electric arc furnace, and these smoke will be discharged from the electric arc furnace along with the tail gas. The more intense the smelting reaction in the electric arc furnace, the more smoke will be generated and the higher the temperature. At this time, the smoke content and temperature of the tail gas discharged from the electric arc furnace are higher. The pressure of the tail gas increases with the increase of the smoke content and temperature. If the tail gas cannot be adsorbed quickly and timely during the process of collecting the tail gas, the tail gas will accumulate inside the electric arc furnace, reducing the smelting reaction efficiency inside the electric arc furnace. At the same time, it will also increase the pressure inside the electric arc furnace. Once the internal pressure of the electric arc furnace exceeds the maximum pressure threshold that the furnace body can withstand, the electric arc furnace will be at risk of explosion. In addition, if the tail gas cannot be adsorbed quickly and comprehensively during the process of collecting the tail gas, tail gas leakage may occur, causing environmental pollution problems. Considering that the smoke content and temperature in the tail gas emitted by the electric arc furnace are related to the reaction intensity in the electric arc furnace, the reaction intensity in the electric arc furnace can be directly and accurately determined by detecting the smelting temperature inside the electric arc furnace. To this end, the smelting temperature data in the electric arc furnace is detected and analyzed, and the smelting temperature data at different positions in the electric arc furnace and the smelting temperature change data at each position over time are obtained to judge the smelting progress inside the electric arc furnace. Generally speaking, the electric arc furnace can be modeled and processed according to the smelting temperature spatial distribution data and smelting temperature time domain change data inside the electric arc furnace to obtain the reaction state estimation model inside the electric arc furnace, thereby determining the smelting progress inside the electric arc furnace. When the smelting progress inside the electric arc furnace indicates that the smelting reaction intensity inside the electric arc furnace is higher than the preset intensity threshold, the frequency of tail gas monitoring of the electric arc furnace is increased; otherwise, the current tail gas monitoring frequency of the electric arc furnace is kept unchanged, so as to monitor the tail gas temperature and tail gas particle concentration emitted by the electric arc furnace, and provide a reliable basis for the subsequent adjustment of the collection parameters of tail gas smoke.

[0045] Preferably, in step S1, adjusting the tail gas and fume collection parameters of the electric arc furnace according to the tail gas emission characteristics includes:

[0046] According to the tail gas temperature and tail gas particle concentration of the electric arc furnace, the pressure change trend of the tail gas discharged from the electric arc furnace is predicted;

[0047] According to the pressure change trend of the exhaust gas emitted by the electric arc furnace, it is judged whether the exhaust gas emitted by the electric arc furnace is in an abnormal pressure state; when it is in an abnormal pressure state, the negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are adjusted; when it is not in an abnormal pressure state, the current negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are kept unchanged.

[0048] The beneficial effects of the above technical solution are as follows: the tail gas emitted by the electric arc furnace is a high-temperature dense smoke gas. The higher the temperature of the tail gas and the higher the concentration of smoke particles, the higher the gas pressure of the tail gas. The smelting reaction inside the electric arc furnace cannot always maintain a stable state. In a certain time interval of the smelting reaction, the reaction intensity may be more intense, resulting in a high temperature and tail gas particle concentration of the tail gas emitted by the electric arc furnace. At this time, the gas pressure of the tail gas emitted by the electric arc furnace is also high. If the tail gas cannot be timely adsorbed and collected according to the gas pressure of the tail gas at this time, the tail gas may continue to accumulate inside the electric arc furnace, causing safety problems. For this reason, the pressure change trend of the tail gas emitted by the electric arc furnace is first predicted based on the tail gas temperature and tail gas particle concentration emitted by the electric arc furnace, so as to determine whether the tail gas emitted by the electric arc furnace is in an abnormal state of excessive pressure. When the exhaust gas emitted by the electric arc furnace is in an abnormal state of excessive pressure, the negative pressure adsorption intensity of the exhaust gas and smoke collection of the electric arc furnace is increased and the cooling temperature of the exhaust gas and smoke collection of the electric arc furnace is reduced. By cooling the collected exhaust gas and smoke, the exhaust pressure can be effectively reduced, and combined with a higher negative pressure adsorption intensity, the collection efficiency of the exhaust gas and smoke can be improved to prevent the exhaust gas and smoke from leaking and flowing back into the electric arc furnace. When the exhaust gas emitted by the electric arc furnace is not in an abnormal state of excessive pressure, the current negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are kept unchanged, thereby maintaining the stability and continuity of the collection of the exhaust gas and smoke.

[0049] Preferably, in step S2, the collected smoke is pretreated in an alkaline environment to obtain an alkaline solution, comprising:

[0050] The collected smoke is cooled and allowed to stand, then dissolved in a KOH solution, and the KOH solution is heated to obtain an alkaline solution; wherein the heating temperature of the KOH solution is not less than 120°C.

[0051] The beneficial effect of the above technical solution is that the collected exhaust smoke needs to be cooled and left to stand before it can be completely deposited and gathered, and then the smoke is dissolved in the KOH solution. At this time, the gallium-containing compounds in the smoke will react in a strong alkaline environment. In order to increase the reaction speed inside the solution, the KOH solution needs to be heated to not less than 120°C, which can improve the activity of the solution and the dissolution efficiency of the smoke in the solution, thereby ensuring that the gallium-containing compounds in the smoke react quickly with KOH.

[0052] Preferably, in step S2, the alkaline solution is subjected to acidification and reaction until a precipitate is generated in the solution, comprising:

[0053] During the heat preservation process of the alkaline solution, carbon dioxide is input to react so that the pH value of the alkaline solution drops to less than or equal to 8 until a precipitate is generated in the solution.

[0054] The beneficial effect of the above technical solution is as follows: after the smoke is fully dissolved and reacted in the KOH solution, carbon dioxide gas is input into the alkaline solution while the alkaline solution is kept warm. After the input carbon dioxide gas is dissolved in water to form carbonic acid, the carbonic acid will react with the alkaline solution to neutralize it, so that the pH value of the alkaline solution gradually decreases from strong alkalinity to less than or equal to 8. At the same time, the gallium ions in the alkaline solution will combine with carbonate ions to form precipitates, thereby realizing the precipitation of gallium elements from the alkaline solution, providing raw materials for the subsequent extraction of metallic gallium.

[0055] Preferably, in step S2, the temperature of the heat preservation treatment is 80-90°C, and the flow rate of the carbon dioxide input into the alkaline solution is at least 1 L / min.

[0056] The beneficial effects of the above technical solution are: the temperature of the insulation treatment is set to 80-90°C, and the flow rate of carbon dioxide input into the alkaline solution is set to at least 1L / min, which can provide suitable temperature conditions for the neutralization reaction of carbonic acid and alkaline solution, and ensure that the alkaline solution obtains a continuous and stable supply of carbon dioxide, so that there is sufficient carbonic acid to react with the alkaline solution.

[0057] Preferably, in step S3, the solution is filtered and separated into a precipitate and a filtrate, and the precipitate is subjected to leaching and neutralization treatment to obtain a gallium-containing mineral, comprising:

[0058] The solution is centrifuged and filtered to obtain a precipitate and a filtrate; wherein the centrifugal rotation speed of the centrifugal precipitation is 300-500 r / min;

[0059] The precipitate is immersed in a sulfuric acid solution for dissolution treatment to obtain a leaching solution; the leaching solution is subjected to a pH neutralization treatment so that the pH value of the leaching solution becomes 7-8; the neutralized leaching solution is filtered to obtain a gallium-containing mineral.

[0060] The beneficial effects of the above technical solution are as follows: the solution is centrifuged and filtered to efficiently precipitate and collect the gallium-containing precipitate in the solution to obtain a precipitate and a filtrate. The precipitate is immersed in a sulfuric acid solution for dissolution treatment to obtain a leaching solution, so that the gallium-containing precipitate is pickled with sulfuric acid to effectively remove impurities in the gallium-containing precipitate. A weak alkaline solution such as ammonia water is then added to the leaching solution for pH neutralization treatment, so that the pH value of the leaching solution becomes 7-8, and the neutralized leaching solution is filtered to obtain a gallium-containing mineral, which can greatly reduce the impurity concentration of the gallium-containing mineral and increase the subsequent metal gallium extraction yield.

[0061] Preferably, in step S3, electrolytic extraction is performed on the gallium-containing mineral to obtain metallic gallium, comprising:

[0062] After dissolving the gallium-containing mineral in an alkaline solution, the alkaline solution is electrolytically extracted to obtain a metallic gallium extract, and then the metallic gallium extract is refined and purified to obtain metallic gallium.

[0063] The beneficial effects of the above technical solution are: dissolving the gallium-containing mineral in an alkaline solution environment, and electrolyzing the alkaline solution to obtain a metallic gallium extract, thereby achieving the preliminary extraction of metallic gallium. The metallic gallium extract is also refined and purified to obtain high-purity metallic gallium, thereby achieving effective enrichment of metallic gallium and improving the extraction efficiency and yield of metallic gallium.

[0064] Preferably, in step S4, the filtrate is subjected to neutralization treatment and reaction treatment to obtain a potassium salt solution, comprising:

[0065] Ammonia water is added to the filtrate for neutralization treatment until the pH value of the filtrate becomes 7-8; the neutralized filtrate is heated for reaction treatment to promote the reaction between potassium ions and ammonium ions in the filtrate to obtain a potassium salt solution.

[0066] The beneficial effects of the above technical solution are as follows: the filtrate is rich in potassium ions. In order to avoid wasting potassium resources, potassium ions need to be extracted from the filtrate. For this purpose, ammonia water is added to the filtrate for neutralization treatment until the pH value of the filtrate becomes 7-8; the neutralized filtrate is heated for reaction treatment to promote the potassium ions in the filtrate to react with ammonium ions to obtain a potassium salt solution, which can ensure that the potassium ions are effectively extracted.

[0067] Preferably, in step S4, the potassium salt solution is subjected to crystallization extraction to obtain potash fertilizer, comprising:

[0068] The potassium salt solution is subjected to thermal evaporation treatment to obtain potassium salt crude material; the potassium salt crude material is subjected to secondary dissolution and crystallization purification treatment to obtain potassium fertilizer.

[0069] The beneficial effects of the above technical scheme are: the potassium salt solution is subjected to thermal evaporation treatment to obtain potassium salt crude material, and the potassium salt crude material is subjected to secondary dissolution and crystallization purification treatment to obtain potassium fertilizer, thereby ensuring that the extracted potassium salt can be directly used for agricultural fertilization and improving the utilization efficiency of the potassium salt.

[0070] It can be seen from the contents of the above embodiments that the brown corundum smelting smoke recovery method monitors the exhaust emission characteristics of the brown corundum smelting arc furnace, and adjusts the exhaust smoke collection parameters of the arc furnace; pre-treats the collected smoke into an alkaline solution, and acidifies and reacts the alkaline solution until a precipitate is generated in the solution; filters the solution to separate it into a precipitate and a filtrate, treats the precipitate to obtain a gallium-containing mineral, and then obtains metallic gallium by electrolytic extraction; treats the filtrate to obtain a potassium salt solution, and then obtains potash fertilizer by crystallization extraction. By performing dynamic tail gas emission detection on the arc furnace, the tail gas smoke can be efficiently and comprehensively collected, and the smoke leakage during the tail gas collection process can be minimized. By dissolving and reacting the smoke in a solution environment, and adjusting the acid-base properties of the solution, the gallium element is precipitated, the gallium metal extraction efficiency and purity are improved, and potash fertilizer is additionally formed, thereby increasing the variety and output of smoke recovery products.

[0071] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for recovering brown corundum smelting dust, characterized in that: It includes the following steps: Step S1, monitoring the tail gas of the brown corundum smelting arc furnace to obtain the tail gas emission characteristics; According to the exhaust gas emission characteristics, adjusting the exhaust gas and smoke collection parameters of the electric arc furnace; Step S2, pre-treating the collected smoke in an alkaline environment to obtain an alkaline solution; Acidifying and reacting the alkaline solution until a precipitate is generated in the solution; Step S3, filtering the solution to separate into a precipitate and a filtrate, and performing leaching and neutralization treatment on the precipitate to obtain a gallium-containing mineral; Electrolytically extracting the gallium-containing mineral to obtain metallic gallium; Step S4, neutralizing and reacting the filtrate to obtain a potassium salt solution; The potassium salt solution is subjected to crystallization extraction to obtain potash fertilizer.

2. The method for recovering brown corundum smelting dust according to claim 1, characterized in that: In the step S1, tail gas monitoring is performed on the brown corundum smelting arc furnace to obtain tail gas emission characteristics, including: Detect and analyze the smelting temperature data inside the arc furnace for smelting brown corundum to determine the smelting progress inside the arc furnace; wherein the smelting temperature data includes the smelting temperature spatial distribution data and the smelting temperature time domain variation data inside the arc furnace; According to the smelting progress, the frequency of tail gas monitoring of the electric arc furnace is adjusted, and the tail gas emission characteristics of the electric arc furnace are obtained; wherein the tail gas emission characteristics include the tail gas temperature and tail gas particle concentration emitted by the electric arc furnace.

3. The method for recovering brown corundum smelting dust as claimed in claim 2, characterized in that: In the step S1, adjusting the tail gas and smoke collection parameters of the electric arc furnace according to the tail gas emission characteristics includes: According to the tail gas temperature and tail gas particle concentration of the electric arc furnace, the pressure change trend of the tail gas discharged from the electric arc furnace is predicted; According to the pressure change trend of the exhaust gas emitted by the electric arc furnace, it is judged whether the exhaust gas emitted by the electric arc furnace is in an abnormal pressure state; when it is in an abnormal pressure state, the negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are adjusted; when it is not in an abnormal pressure state, the current negative pressure adsorption intensity and cooling temperature of the exhaust gas and smoke collection of the electric arc furnace are kept unchanged.

4. The method for recovering brown corundum smelting dust according to claim 1, characterized in that: In step S2, the collected smoke is pretreated in an alkaline environment to obtain an alkaline solution, including: The collected smoke is cooled and allowed to stand, then dissolved in a KOH solution, and the KOH solution is heated to obtain an alkaline solution; wherein the heating temperature of the KOH solution is not less than 120°C.

5. The method for recovering brown corundum smelting dust according to claim 4, characterized in that: In step S2, the alkaline solution is subjected to acidification and reaction until a precipitate is generated in the solution, comprising: During the heat preservation process of the alkaline solution, carbon dioxide is input to react so that the pH value of the alkaline solution drops to less than or equal to 8, until a precipitate is generated in the solution.

6. The method for recovering brown corundum smelting dust according to claim 5, characterized in that: In the step S2, the temperature of the heat preservation treatment is 80-90°C, and the flow rate of the carbon dioxide input into the alkaline solution is at least 1 L / min.

7. The method for recovering brown corundum smelting dust according to claim 1, characterized in that: In step S3, the solution is filtered and separated into a precipitate and a filtrate, and the precipitate is subjected to leaching and neutralization treatment to obtain a gallium-containing mineral, including: The solution is centrifuged and filtered to obtain a precipitate and a filtrate; wherein the centrifugal rotation speed of the centrifugal precipitation is 300-500 r / min; The precipitate is immersed in a sulfuric acid solution for dissolution treatment to obtain a leaching solution; the leaching solution is subjected to a pH neutralization treatment so that the pH value of the leaching solution becomes 7-8; the neutralized leaching solution is filtered to obtain a gallium-containing mineral.

8. The method for recovering brown corundum smelting dust according to claim 7, characterized in that: In step S3, electrolytic extraction is performed on the gallium-containing mineral to obtain metallic gallium, comprising: After the gallium-containing mineral is dissolved in an alkaline solution, the alkaline solution is subjected to electrolytic extraction to obtain a metallic gallium extract, and then the metallic gallium extract is subjected to refining and purification to obtain metallic gallium.

9. The method for recovering brown corundum smelting dust according to claim 1, characterized in that: In step S4, the filtrate is subjected to neutralization treatment and reaction treatment to obtain a potassium salt solution, comprising: Ammonia water is added to the filtrate for neutralization treatment until the pH value of the filtrate becomes 7-8; the neutralized filtrate is heated for reaction treatment to promote the potassium ions in the filtrate to react with ammonium ions to obtain a potassium salt solution.

10. The method for recovering brown corundum smelting dust according to claim 9, characterized in that: In the step S4, the potassium salt solution is subjected to crystallization extraction to obtain potash fertilizer, comprising: The potassium salt solution is subjected to thermal evaporation treatment to obtain potassium salt crude material; the potassium salt crude material is subjected to secondary dissolution and crystallization purification treatment to obtain potash fertilizer.

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