Method for improving vanadium yield in vanadium extraction tailings

Abstract

The invention belongs to the technical field of vanadium metallurgy, and particularly discloses a method for improving the yield of vanadium in vanadium extraction tailings, which comprises the following steps: (1) grinding the vanadium extraction tailings until the particle size is less than 100 meshes, then adding vanadium-containing fly ash and a small amount of binder, and uniformly mixing to obtain a mixed pellet material; (2) roasting the mixed pellet material in a rotary kiln, and carrying out oxidation reaction at high temperature; and (3) the roasted mixed material is subjected to water leaching treatment, and a vanadium-containing solution is obtained. According to the method, the yield of vanadium in the vanadium extraction tailings can be increased, and meanwhile valuable elements in the vanadium-containing waste resource fly ash can be recycled; the whole technological process is simple and easy to operate, no three wastes are discharged in the whole process, and the method is clean and environmentally friendly and has good economic benefits and application prospects.

Description

Technical Field

[0001] This invention belongs to the field of vanadium metallurgical technology, specifically relating to a method for improving the vanadium yield in vanadium extraction tailings. Background Technology

[0002] Vanadium is an important non-ferrous metal, and vanadium and its alloys are widely used in metallurgy, petrochemicals, defense, and other technological fields. Currently, in the smelting process of vanadium-titanium magnetite, vanadium slag is mostly roasted using the rotary kiln sodium roasting process. After vanadium is extracted from the vanadium slag, the tailings contain relatively high levels of vanadium and iron. If these vanadium-containing solid wastes are not disposed of properly and are simply dumped, they will not only occupy a large amount of land resources and increase the management costs of enterprises, but also cause serious harm to humans and the environment due to the toxicity of vanadium. On the other hand, vanadium-containing solid wastes contain many metals of significant economic value and should be actively recycled and utilized to turn waste into treasure and harm into benefit, thereby creating considerable economic and social benefits.

[0003] Current vanadium extraction tailings recycling processes suffer from drawbacks such as complex operation, long process flow, high energy consumption, and inability to fully utilize the metals in the tailings. Therefore, researching ways to improve the recovery rate of metal elements from vanadium extraction tailings is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a method for improving the vanadium yield in vanadium extraction tailings, which can effectively recover vanadium from the tailings, realize the resource utilization of the tailings, and has a simple process that can be industrialized.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A method for improving the vanadium yield in vanadium extraction tailings includes the following steps: (1) Grind the vanadium extraction tailings to a particle size of less than 100 mesh, then add vanadium-containing dust removal ash and a small amount of binder, and mix evenly to obtain mixed pellet material; (2) The mixed pellet material is placed in a rotary kiln for roasting and oxidation reaction at high temperature; (3) The calcined mixture is subjected to water immersion treatment to obtain a vanadium-containing solution.

[0006] Furthermore, the vanadium element in the vanadium extraction tailings of the present invention, calculated as V2O5, has a content of 1wt% to 2wt%; the water content of the vanadium extraction tailings is 15wt% to 20wt%.

[0007] Furthermore, the vanadium-containing dust ash of the present invention is dust generated during the vanadium-iron smelting process. The vanadium element in the vanadium-containing dust ash, calculated as V2O5, has a content of 28wt% to 40wt%; the sodium element in the vanadium-containing dust ash, calculated as Na2O, has a content of 10wt% to 16wt%.

[0008] Furthermore, the amount of vanadium-containing dust added according to the present invention is 3% to 5% of the mass of the vanadium extraction tailings.

[0009] Furthermore, the binder of the present invention is starch or polyvinyl alcohol, and the amount added is 5 to 8% of the mass of the vanadium extraction tailings.

[0010] Furthermore, the roasting temperature described in this invention is 700–800°C, and air or oxygen is introduced during the roasting process for 3–6 hours.

[0011] Furthermore, the immersion temperature of the present invention is 70-95°C, and the immersion time is 0.5-2 hours; the liquid-to-solid ratio of the water immersion is 3-5:1.

[0012] The inventive principle and beneficial technical effects of this invention are as follows: The dust collector additive used in this invention contains small amounts of sodium and vanadium. By adding a small amount of binder and mixing it with vanadium extraction tailings to form pellets, the oxidation conditions of the vanadium extraction tailings can be improved, promoting the oxidation reaction. Vanadium in the vanadium extraction tailings is more easily converted into soluble vanadates, increasing the vanadium yield from the tailings. At the same time, valuable elements in the vanadium-containing waste dust collector can be recovered and utilized. The entire process is simple, easy to operate, and produces no waste, making it clean and environmentally friendly with good economic benefits and application prospects.

[0013] This invention forms pellets by adding a small amount of binder. The pellets are then processed through a pelletizing-calcining process to form a porous but interconnected skeletal structure, which increases the contact area with oxygen, making the oxidation reaction more complete and controllable, and avoiding uneven oxidation or local oxygen deficiency when the raw material is in powder form.

[0014] During the roasting process, vanadium raw materials and binders undergo a solid-phase reaction to generate composite oxides such as iron vanadate and silicon vanadate. These phases are not easily reduced under an oxidizing atmosphere, which can inhibit the volatilization of low-valence oxides of vanadium, thereby improving the overall tolerance to oxidizing environments. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Example 1

[0016] A method for improving the vanadium yield in vanadium extraction tailings includes the following steps: (1) Take 10g of vanadium extraction tailings and grind them to pass through an 80-mesh sieve; the vanadium content in the vanadium extraction tailings is 1.5% (calculated as V2O5), the sodium content is 1.20% (calculated as Na2O), the potassium content is 0.56%, and the water content is 18%; add 0.3g of vanadium-containing dust removal ash and 0.5g of starch to the vanadium extraction tailings and mix them evenly to obtain mixed pellets; wherein, the vanadium-containing dust removal ash contains 30% vanadium (calculated as V2O5), 12% sodium (calculated as Na2O), and 6.08% potassium.

[0017] (2) Place the mixed pellet material in a rotary kiln, heat it to 800°C and roast it. Then introduce air and oxidize it for 3 hours. After the reaction is completed, the roasted material is obtained.

[0018] (3) Add water at 80°C to the roasted material and soak for 2 hours to obtain a vanadium-containing solution, wherein the mass ratio of water to roasted material is 4:1.

[0019] According to testing and calculation, the recovery rate of vanadium extraction tailings V in this embodiment is 84.8%. Example 2

[0020] A method for improving the vanadium yield in vanadium extraction tailings includes the following steps: (1) Take 10g of vanadium extraction tailings and grind them to pass through a 70-mesh sieve; the vanadium content in the vanadium extraction tailings is 1.8% (calculated as V2O5), the sodium content is 1.15% (calculated as Na2O), the potassium content is 0.60%, and the water content is 19%; add 0.5g of vanadium-containing dust removal ash and 0.8g of starch to the vanadium extraction tailings and mix them evenly to obtain mixed pellets; wherein, the vanadium-containing dust removal ash contains 35% vanadium (calculated as V2O5), 14% sodium (calculated as Na2O), and 6.24% potassium.

[0021] (2) Place the mixed pellet material in a rotary kiln, heat it to 750°C and roast it. Introduce oxygen and oxidize for 4 hours. After the reaction is complete, the roasted material is obtained.

[0022] (3) Add water at 90°C to the roasted material and soak for 1.5 hours to obtain a vanadium-containing solution, wherein the mass ratio of water to roasted material is 4.5:1.

[0023] According to testing and calculation, the recovery rate of vanadium extraction tailings V in this embodiment is 88.6%. Example 3

[0024] A method for improving the vanadium yield in vanadium extraction tailings includes the following steps: (1) Take 10g of vanadium extraction tailings and grind them to pass through a 100-mesh sieve; the vanadium content in the vanadium extraction tailings is 1.7% (calculated as V2O5), the sodium content is 1.06% (calculated as Na2O), the potassium content is 0.48%, and the water content is 18%; add 0.45g of vanadium-containing dust removal ash and 0.6g of starch to the vanadium extraction tailings and mix them evenly to obtain mixed pellets; wherein, the vanadium-containing dust removal ash contains 34% (calculated as V2O5), 15% (calculated as Na2O), and 5.68% potassium.

[0025] (2) Place the mixed pellet material in a rotary kiln, heat it to 780°C and roast it. Then introduce air and oxidize it for 5 hours. After the reaction is completed, the roasted material is obtained.

[0026] (3) Add water at 70°C to the roasted material and soak for 1 hour to obtain a vanadium-containing solution; wherein the mass ratio of water to roasted material is 3:1.

[0027] According to testing and calculation, the recovery rate of vanadium extraction tailings V in this embodiment is 80.5%.

[0028] Comparative Example 1

[0029] A method for recovering vanadium from vanadium extraction tailings includes the following steps: (1) Take 10g of vanadium extraction tailings, grind them to pass through an 80-mesh sieve to obtain the material; wherein, the vanadium content in the vanadium extraction tailings is 1.5% (calculated as V2O5), the sodium content is 1.20% (calculated as Na2O), the potassium content is 0.56%, and the water content is 18%.

[0030] (2) Place the material in a rotary kiln, heat it to 800°C and roast it. Then introduce air and oxidize it for 3 hours. After the reaction is complete, the roasted material is obtained.

[0031] (3) Add water at 80°C to the roasted material and soak for 2 hours to obtain a vanadium-containing solution, wherein the mass ratio of water to roasted material is 4:1.

[0032] According to testing and calculation, the recovery rate of vanadium extraction tailings V in this embodiment is 60.8%.

Claims

1. A method for improving the vanadium yield in vanadium extraction tailings, characterized in that, Includes the following steps: (1) Grind the vanadium extraction tailings to a particle size of less than 100 mesh, then add vanadium-containing dust removal ash and a small amount of binder, and mix evenly to obtain mixed pellet material; (2) The mixed pellet material is placed in a rotary kiln for roasting and oxidation reaction at high temperature; (3) The calcined mixture is subjected to water immersion treatment to obtain a vanadium-containing solution.

2. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The vanadium content in the vanadium extraction tailings, calculated as V2O5, is 1wt% to 2wt%; the water content of the vanadium extraction tailings is 15wt% to 20wt%.

3. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The vanadium in the vanadium-containing dust collector, calculated as V2O5, has a content of 28wt% to 40wt%; the sodium in the vanadium-containing dust collector, calculated as Na2O, has a content of 10wt% to 16wt%.

4. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The amount of vanadium-containing dust added is 3% to 5% of the mass of the vanadium extraction tailings.

5. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The binder is starch or polyvinyl alcohol, and the amount added is 5-8% of the mass of the vanadium extraction tailings.

6. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The roasting temperature is 700-800℃, and air or oxygen is introduced during the roasting process, which lasts for 3-6 hours.

7. The method for improving the vanadium yield in vanadium extraction tailings according to claim 1, characterized in that, The immersion temperature is 70–95°C, and the immersion time is 0.5–2 hours; the liquid-to-solid ratio of the water immersion is 3–5:1.