Method for clean vanadium extraction from blast furnace vanadium slag

Abstract

The invention discloses a method for clean vanadium extraction from blast furnace vanadium slag, which comprises the following steps: crushing the vanadium slag by using a ball mill, and sieving to obtain coarsely separated vanadium slag powder; carrying out blank roasting on the coarsely separated vanadium slag powder, and then crushing and sieving to obtain vanadium slag clinker; preparing leachate, adding vanadium slag clinker, and performing solid-liquid separation after the leaching reaction is finished to obtain filter residues and vanadium-containing leaching mother liquor; and the filter residues obtained in the third step are washed, washing liquor is collected, and secondary vanadium-containing leaching mother liquor is obtained. Vanadium in the vanadium slag is efficiently, simply and conveniently leached through a vanadium slag clean roasting vanadium extraction process, and the vanadium slag with high extraction cost is converted into a sodium vanadate solution with high additional value and high performance in an efficient and low-cost mode; compared with sodium salt roasting, calcification roasting, liquid phase oxidation, ion extraction and other modes, the method does not relate to roasting tail gas emission, high temperature and high pressure and organic matter introduction, the crystal form of the substance is ingeniously changed through the property of the substance and the temperature change, and then the target element is leached.

Description

Technical Field

[0001] The invention belongs to the technical field of vanadium extraction chemical industry, and more specifically, the invention relates to a method for cleanly extracting vanadium from blast furnace vanadium slag. Background Art

[0002] Vanadium slag is a general term for the vanadium oxide-containing slag obtained by oxidative blowing of vanadium-containing molten iron in the process of vanadium extraction or by wet vanadium extraction of vanadium-containing iron concentrate. It is the raw material for smelting and producing vanadium alloys and metallic vanadium. Its physical state is usually block or powder. The particle size of block vanadium slag shall not be greater than 200mm×200mm. The particle size and metallic iron content of powder vanadium slag shall be agreed upon by both the supply and demand parties. The main components of vanadium slag include vanadium pentoxide (V2O5), silicon dioxide (SiO2), calcium oxide (CaO), etc.

[0003] At present, the common method of extracting vanadium from vanadium slag on the market is sodium roasting. Patent CN116445713A discloses a system for removing impurities from vanadium pentoxide prepared from sodium roasting water leaching liquid of vanadium slag, which uses sodium roasting ingredients at high temperature and then leaching to obtain vanadium-containing mother liquor. This method has high energy consumption, and sodium roasting produces a large amount of gas emissions, which is not conducive to environmental protection. Patent CN113981250A discloses a method for extracting vanadium by sodium-fermentation roasting of vanadium slag, which comprises pouring the vanadium slag into a multi-stage vertical mill for full grinding to obtain vanadium slag powder; removing elemental iron from the vanadium slag powder by multiple magnetic separations; mixing the iron-removed vanadium slag powder with sodium carbonate in a proportion, and roasting it in a rotary kiln; after the roasting reaction, mixing the roasted clinker with water to prepare a slurry, and pouring the slurry into a self-priming stirred reactor for leaching reaction; after the leaching reaction, performing solid-liquid separation on the slurry to obtain a sodium vanadate solution and vanadium-extracted tailings. The method has relatively complicated steps, and iron removal is required before sodium-fermentation batching, which greatly increases the burden of production costs. Patent CN113913620A discloses a method for extracting vanadium from vanadium slag by sodiumization, wherein sodium bisulfate and vanadium slag are mixed in a molar ratio of Na:V=1-3:1, mixed evenly, and calcined in an oxidizing atmosphere for 1-3 hours to obtain clinker, and the clinker is leached at a liquid-to-solid ratio (mL / g) of 1-3:1 at a temperature of 80-100°C, filtered to obtain a vanadium-containing solution and vanadium-extracting tailings; the residual vanadium content of the vanadium-extracting tailings is detected, and the vanadium extraction rate is calculated; the vanadium-containing solution is treated for vanadium extraction, and the vanadium-extracting tailings are disposed of. In this method, gas recovery is difficult after high-temperature roasting of the sodiumization additive sodium bisulfate, and the treatment cost is high. Patent CN115477326A discloses a method for preparing a high-purity vanadyl sulfate solution from an industrial vanadium slag calcified roasting acid leaching liquid, comprising the steps of adding a desiliconizing agent to the industrial vanadium slag calcified acid leaching liquid to remove silicon in the industrial vanadium slag calcified acid leaching liquid, stirring, standing, and filtering to obtain a leaching liquid; preparing a microemulsion with a quaternary ammonium salt, a medium-chain alcohol, an oil phase, and a mixed aqueous solution of NaOH and NaCl; mixing the obtained microemulsion with the leaching liquid, shaking for a certain period of time for extraction, standing for stratification, the upper phase being the microemulsion phase, and the lower phase being the aqueous phase, and separating the microemulsion phase and the aqueous phase; washing, reducing, and stripping the upper microemulsion phase to prepare a high-purity vanadyl sulfate solution. The method uses an organic solvent for extraction, and subsequent vanadium and chromium separation requires a greater cost, and the wastewater COD is relatively high, and the discharge treatment process is difficult. Patent CN101402470A discloses a method for producing vanadium oxide by utilizing ion exchange to realize wastewater recycling. In this method, vanadium slag or other vanadium-containing raw materials are mixed with additives to obtain a mixed material, wherein the CaO / V2O5 weight ratio in the mixed material reaches 0.5 to 1.4, and then the mixed material is subjected to calcification roasting, leaching, solid-liquid separation, and ion exchange to remove impurities to obtain a vanadium-containing solution. This method has a lengthy process, a short service life of the ion exchange membrane, and a high cost for recycling the membrane resin after use.

[0004] In summary, the methods of sodiumization, calcification and liquid phase extraction mentioned above all have cost, safety and technical problems in the production process. There is an urgent need for a vanadium slag vanadium extraction process with a simple process route, low energy consumption, and a safe and reliable production process. Summary of the invention

[0005] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0006] In order to achieve these purposes and other advantages of the present invention, a method for clean vanadium extraction from blast furnace vanadium slag is provided, comprising the following steps:

[0007] Step 1, grinding the vanadium slag with a ball mill and then sieving to obtain coarse vanadium slag powder;

[0008] Step 2: blank roasting the coarse vanadium slag powder, and then crushing and sieving to obtain vanadium slag clinker;

[0009] Step 3, preparing a leaching solution, adding vanadium slag clinker, and after the leaching reaction is completed, solid-liquid separation is performed to obtain filter residue and vanadium-containing leaching mother liquor;

[0010] Step 4: Wash the filter residue obtained in step 3, and collect the washing liquid to obtain a secondary vanadium-containing leaching mother liquor.

[0011] Preferably, in step 1, the vanadium slag is tailings obtained from blast furnace ironmaking, and its components include: a total vanadium content of 10-15%, a total chromium content of 4-10%, and a SiO2 content of 12-18%.

[0012] Preferably, in step 1, the sieving is through a 50-300 mesh vibrating sieve.

[0013] Preferably, in step 2, the blank roasting is dynamic roasting or microwave static roasting.

[0014] Preferably, the specific method of dynamic roasting is: controlling the temperature and heating time by adjusting the kiln speed and natural gas opening, wherein the kiln speed is 20-30 Hz, the preheating zone temperature is 300-500°C, the preheating time is 30-90 min, the firing zone temperature is 700-1150°C, and the time passing through the firing zone is 30-120 min.

[0015] Preferably, the specific method of the microwave static roasting is: uniformly heating to 700-1150° C. at a rate of 10-15° C. / min and keeping the temperature, and the total heating and keeping time is 100-300 min.

[0016] Preferably, in the step 2, the powder is crushed through a 50-200 mesh vibrating screen.

[0017] Preferably, in step three, the leaching medium of the leaching solution is one or more of sodium carbonate, sodium bicarbonate, sodium sulfate, sodium bisulfate, sulfuric acid, and sodium hydroxide.

[0018] Preferably, in step three, the concentration of the leaching solution is 100-300 g / L; the mass ratio of the vanadium slag clinker to the leaching solution is 1:1-10; the temperature of the leaching reaction is 60-100° C., and the reaction time is 30-240 min.

[0019] Preferably, in step 4, the specific method of washing the filter residue obtained in step 3 is: adopting three-stage countercurrent washing, the volume ratio of filter residue to washing water is 1:1-2, and the washing water temperature is 40-100°C.

[0020] Preferably, the step 2 is replaced by: blank roasting the coarse vanadium slag powder, then entering into a plasma ball mill, performing room temperature plasma ball milling in a mixed atmosphere of oxygen and argon at 0.1 to 0.5 MPa, and sieving after ball milling to obtain vanadium slag clinker; wherein the specific parameters of the plasma ball milling are: a volume ratio of oxygen to argon of 1 to 2:8 to 9, a discharge voltage of 8 to 15 kV, a discharge current of 0.5 to 2 A, a discharge frequency of 22 to 28 kHz, a rotation speed of 600 to 1000 rpm, a ball-to-material ratio of 5 to 20:1, and the grinding balls are any one of stainless steel balls, tungsten carbide balls, zirconium oxide balls, and agate balls.

[0021] The present invention has at least the following beneficial effects:

[0022] (1) The present invention uses a vanadium slag clean roasting vanadium extraction process to efficiently and conveniently leach vanadium from vanadium slag, and converts vanadium slag with high extraction cost into high value-added and high-performance sodium vanadate solution in an efficient and low-cost manner; compared with sodium roasting, calcium roasting, liquid phase oxidation, ion extraction and other methods, the present invention does not involve roasting tail gas emissions, high temperature and high pressure, and the introduction of organic matter, and uses the properties of the substance itself to cleverly change its crystal form by temperature changes to leach the target element.

[0023] (2) The inventors have conducted SEM and XRD analyses on a large number of samples and verified through a large number of experiments that the insoluble elements such as vanadium and chromium in the vanadium slag will be converted into high-priced and easily leached vanadium pentoxide and sodium chromate after being roasted at a certain temperature. Under this process condition, the chromium in the vanadium slag can be extracted simultaneously with the vanadium extraction.

[0024] (3) The present invention obtains vanadium slag clinker by blank roasting without adding additives, and no additional roasting aids are needed. Firstly, the roasting cost is reduced, and secondly, there is no large amount of carbon emission and sulfur emission during the roasting process, which is more environmentally friendly.

[0025] (4) The roasting temperature of the present invention is not high and the crystal deformation time is short, which has energy advantages over sodium roasting and calcium roasting, saves product output time and reduces energy costs, and has great advantages in large-scale production.

[0026] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0028] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0029] The vanadium slag used in the following examples is the tailings obtained from blast furnace ironmaking, and its composition is shown in Table 1.

[0030] Table 1

[0031]

[0032] Example 1

[0033] A method for cleanly extracting vanadium from blast furnace vanadium slag comprises the following steps:

[0034] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0035] Step 2: Dynamically roast the coarse vanadium slag powder by adjusting the kiln speed and natural gas opening to control the temperature and the heating time of the vanadium slag. The kiln speed is controlled to be 24Hz, the preheating zone temperature is 400℃, the preheating time is 60min, the firing zone temperature is 850℃, and the firing zone time is 60min.

[0036] Step 3: The vanadium slag discharged from the kiln head is cooled by a slag cooler and then crushed in a mill. After crushing, it is passed through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker;

[0037] Step 4: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 3.36 tons of sodium carbonate to obtain sodium carbonate leaching solution, add vanadium slag clinker at a mass ratio of vanadium slag clinker to sodium carbonate leaching solution of 1:2, leach for 120 minutes at 95°C to obtain vanadium solution;

[0038] Step 5: solid-liquid separation is performed on the vanadium solution obtained in step 4, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 75.4 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 53.2 g / L; the final vanadium conversion rate is 94.33%, and the chromium conversion rate is 79.82%.

[0039] Example 2

[0040] A method for cleanly extracting vanadium from blast furnace vanadium slag comprises the following steps:

[0041] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0042] Step 2: The coarse vanadium slag powder is subjected to microwave static roasting. The heating time of the vanadium slag is controlled by adjusting the roller speed and the heating rate. The temperature is uniformly raised to 850°C at a rate of 12°C / min and kept warm. The total heating and keeping time is 200min.

[0043] Step 3: The discharged sagger vanadium slag is removed from the mold by a mechanical arm, and then enters a grinder for crushing. After crushing, it passes through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker;

[0044] Step 4: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 3.2 tons of sodium bicarbonate to obtain sodium bicarbonate leaching solution, add vanadium slag clinker at a mass ratio of vanadium slag clinker to sodium bicarbonate leaching solution of 1:2, leach for 120 minutes at 95°C to obtain vanadium solution;

[0045] Step 5: solid-liquid separation is performed on the vanadium solution obtained in step 4, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 88.65 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 51.32 g / L; the final vanadium conversion rate is 92.06%, and the chromium conversion rate is 75.43%.

[0046] Example 3

[0047] A method for cleanly extracting vanadium from blast furnace vanadium slag comprises the following steps:

[0048] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0049] Step 2: The coarse vanadium slag powder is subjected to microwave static roasting. The heating time of the vanadium slag is controlled by adjusting the roller speed and the heating rate. The temperature is uniformly raised to 850°C at a rate of 12°C / min and kept warm. The total heating and keeping time is 200min.

[0050] Step 3: The discharged sagger vanadium slag is removed from the mold by a mechanical arm, and then enters a grinder for crushing. After crushing, it passes through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker;

[0051] Step 4: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 2.8 tons of sodium bicarbonate to obtain sodium bicarbonate leaching solution, add vanadium slag clinker at a mass ratio of vanadium slag clinker to sodium bicarbonate leaching solution of 1:4, leach for 120 minutes at 95°C to obtain vanadium solution;

[0052] Step 5: solid-liquid separation is performed on the vanadium solution obtained in step 4, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 85.3 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 54.09 g / L; the final vanadium conversion rate is 93.6%, and the chromium conversion rate is 75.84%.

[0053] Example 4

[0054] A method for cleanly extracting vanadium from blast furnace vanadium slag comprises the following steps:

[0055] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0056] Step 2: The coarse vanadium slag powder is subjected to microwave static roasting. The heating time of the vanadium slag is controlled by adjusting the roller speed and the heating rate. The temperature is uniformly raised to 850°C at a rate of 12°C / min and kept warm. The total heating and keeping time is 200min.

[0057] Step 3: The discharged sagger vanadium slag is removed from the mold by a mechanical arm, and then enters a grinder for crushing. After crushing, it passes through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker;

[0058] Step 4: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 4 tons of sodium bicarbonate to obtain sodium bicarbonate leaching solution, add vanadium slag clinker at a mass ratio of vanadium slag clinker to sodium bicarbonate leaching solution of 1:4, leach for 120 minutes at 95°C to obtain vanadium solution;

[0059] Step 5: solid-liquid separation is performed on the vanadium solution obtained in step 4, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 87.56 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 49.71 g / L; the final vanadium conversion rate is 92.34%, and the chromium conversion rate is 78.21%.

[0060] Example 5

[0061] In this embodiment, step three is replaced by: the vanadium slag discharged from the kiln head is cooled by a slag cooler and then enters a plasma ball mill, and is subjected to room temperature plasma ball milling in a mixed atmosphere of 0.3 MPa oxygen and argon, and after ball milling, it is passed through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker; wherein the specific parameters of the plasma ball mill are: the volume ratio of oxygen to argon is 2:8, the discharge voltage is 10 kV, the discharge current is 1 A, the discharge frequency is 26 kHz, the rotation speed is 800 rpm, the ball-to-material ratio is 10:1, and the grinding balls are stainless steel balls; the remaining steps are the same as in Example 1. The final vanadium conversion rate is 96.85%, and the chromium conversion rate is 81.24%.

[0062] In this embodiment, the vanadium slag that has undergone blank roasting is subjected to plasma ball milling treatment. The ball milling efficiency is high, and the vanadium slag clinker particles are more evenly dispersed, and the subsequent leaching reaction is more thorough. At the same time, in a mixed atmosphere of oxygen and argon, the vanadium in the vanadium slag is further converted into high-valent vanadium, thereby improving the vanadium leaching rate.

[0063] Example 6

[0064] In this embodiment, step three is replaced by: the discharged sagger vanadium slag is demoulded by a mechanical arm and then enters a plasma ball mill, and is subjected to room temperature plasma ball milling in a mixed atmosphere of 0.1 MPa oxygen and argon, and after ball milling, it is passed through a double-layer 100-mesh vibrating screen to obtain vanadium slag clinker; wherein the specific parameters of the plasma ball milling are: the volume ratio of oxygen to argon is 1:9, the discharge voltage is 15 kV, the discharge current is 1.5 A, the discharge frequency is 22 kHz, the rotation speed is 800 rpm, the ball-to-material ratio is 10:1, and the grinding balls are stainless steel balls; the remaining steps are the same as in Example 2. The final vanadium conversion leaching rate is 95.24%, and the chromium conversion leaching rate is 77.61%.

[0065] Comparative Example 1

[0066] This comparative example does not undergo blank calcination, and the remaining steps are the same as those of Example 1, including the following steps:

[0067] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0068] Step 2: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 3.36 tons of sodium carbonate to obtain sodium carbonate leaching solution, add coarse vanadium slag powder at a mass ratio of coarse vanadium slag powder to sodium carbonate leaching solution of 1:2, leach for 120 minutes at 95°C to obtain vanadium solution;

[0069] Step 3: solid-liquid separation is performed on the vanadium solution obtained in step 2, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 70.32 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 55.08 g / L; the final vanadium conversion rate is 90.33%, and the chromium conversion rate is 75.33%.

[0070] Comparative Example 2

[0071] This comparative example does not undergo blank calcination, and the remaining steps are the same as those of Example 2, including the following steps:

[0072] Step 1: Grind the vanadium slag with a ball mill until it passes through a 200-mesh vibrating screen to obtain coarse vanadium slag powder;

[0073] Step 2: Add 20 ml of pure water into the reaction tank. 3 , start stirring and steam heating, add 3.2 tons of sodium bicarbonate to obtain sodium bicarbonate leaching solution, add coarse vanadium slag powder at a mass ratio of coarse vanadium slag powder to sodium bicarbonate leaching solution of 1:2, leach for 120 minutes at 95°C to obtain vanadium solution;

[0074] Step 3: solid-liquid separation is performed on the vanadium solution obtained in step 2, and after two-stage separation, a filter residue and a vanadium-containing leaching mother liquor are obtained, the vanadium content of the vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 83.42 g / L, the filter residue is subjected to three-stage countercurrent washing with 60° C. washing water at a volume ratio of 1:1, and the washing liquid is collected to obtain a secondary vanadium-containing leaching mother liquor, the vanadium content of the secondary vanadium-containing leaching mother liquor (in terms of vanadium pentoxide) is 62.19 g / L; the final vanadium conversion rate is 89.83%, and the chromium conversion rate is 72.27%.

[0075] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the embodiments shown and described herein.

Claims

1. A method for clean vanadium extraction from blast furnace vanadium slag, characterized in that: The following steps are involved: Step 1, grinding the vanadium slag with a ball mill and then sieving to obtain coarse vanadium slag powder; Step 2, blank roasting the coarse vanadium slag powder, and then crushing and sieving to obtain vanadium slag clinker; Step 3, preparing a leaching solution, adding vanadium slag clinker, and after the leaching reaction is completed, solid-liquid separation is performed to obtain filter residue and vanadium-containing leaching mother liquor; Step 4: Wash the filter residue obtained in step 3, and collect the washing liquid to obtain a secondary vanadium-containing leaching mother liquor.

2. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 1, the vanadium slag is the tailings obtained from blast furnace ironmaking, and its components include: a total vanadium content of 10-15%, a total chromium content of 4-10%, and a SiO2 content of 12-18%.

3. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 1, the sieving is performed through a 50-300 mesh vibrating sieve.

4. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 2, the blank roasting is dynamic roasting or microwave static roasting.

5. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 4, characterized in that: The specific method of dynamic roasting is: controlling the temperature and heating time by adjusting the kiln speed and natural gas opening, wherein the kiln speed is 20-30Hz, the preheating zone temperature is 300-500°C, the preheating time is 30-90min, the firing zone temperature is 700-1150°C, and the time passing through the firing zone is 30-120min.

6. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 4, characterized in that: The specific method of microwave static roasting is: uniformly heating the temperature to 700-1150° C. at a rate of 10-15° C. / min and keeping the temperature, and the total heating and keeping time is 100-300 minutes.

7. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 2, the pulverized product is passed through a 50-200 mesh vibrating screen.

8. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 3, the leaching medium of the leaching solution is one or more of sodium carbonate, sodium bicarbonate, sodium sulfate, sodium bisulfate, sulfuric acid, and sodium hydroxide.

9. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 3, the concentration of the leaching solution is 100-300 g / L; the mass ratio of the vanadium slag clinker to the leaching solution is 1:1-10; the temperature of the leaching reaction is 60-100° C., and the reaction time is 30-240 min.

10. The method for clean vanadium extraction from blast furnace vanadium slag according to claim 1, characterized in that: In the step 4, the specific method of washing the filter residue obtained in the step 3 is: using three-stage countercurrent washing, the volume ratio of the filter residue to the washing water is 1:1-2, and the washing water temperature is 40-100°C.

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