Method for increasing vanadium content in converter vanadium slag

Abstract

The method for increasing the vanadium content in the converter vanadium slag comprises the steps that S1, a dephosphorizing agent and a cooling agent are added into vanadium-containing molten iron in a converter for oxygen blowing smelting, and molten vanadium slag and semi-steel are obtained; wherein the content of P in the semi-steel is lower than 0.005 wt%; the content of CaO in the molten vanadium slag is greater than 5wt%, and the content of P is greater than 0.05 wt%; s2, adding a high-valence oxide-containing material into the obtained molten vanadium slag, introducing CO2-O2 gas, stirring, and reacting at a set temperature; in the reaction period, the reaction process is enhanced through cooperation of ultrasound, microwaves and a magnetic field, and a mixture of magnetic vanadium spinel and fused silicate is obtained through reaction; the content of the magnetic solid vanadium spinel is 20-100 wt%; and S3, the magnetic vanadium spinel and molten silicate mixture is separated under the magnetic field condition, and the magnetic vanadium spinel and the molten silicate are obtained respectively.

Description

Technical Field

[0001] The present invention belongs to the technical field of iron and steel smelting, and particularly relates to a method for increasing the vanadium content in converter vanadium slag. Background Art

[0002] Vanadium has important applications in industries such as iron and steel, batteries, and catalysts. Chromium can improve the oxidation resistance and corrosion resistance of steel and is an important alloying element for heat-resistant steel.

[0003] Vanadium-titanium magnetite is a complex symbiotic mineral rich in various valuable components such as iron, vanadium, chromium, and titanium. Vanadium slag contains valuable metals vanadium and chromium. The V 2 O 3 content in vanadium slag is 13-19 wt.%. The main phases of vanadium slag are spinel phase (ferrovanadium spinel, manganese-vanadium spinel, and titanoferrite spinel), silicate phase (manganese-ferrous olivine), and metallic iron phase; vanadium mainly exists in the form of trivalent in ferrovanadium spinel (FeV 2 O 4 ).

[0004] Patent CN201310416429.4 discloses a method for separating vanadium resources in vanadium slag by high gravity, which discloses that molten vanadium slag is centrifugally separated from spinel phase and silicate phase at 1240-1260 °C; Patent CN201610807157.4 discloses a method for dephosphorizing vanadium-containing hot metal in a converter for vanadium extraction, which discloses dephosphorization by controlling the oxygen lance and adding scale; Patent CN201210239175.9 discloses a method for simultaneous dephosphorization and vanadium extraction in a converter, which discloses adding dephosphorizing agent lime to vanadium-containing hot metal in the converter during the vanadium extraction process for simultaneous dephosphorization and vanadium extraction; Patent CN201210238253.3 discloses a coolant and production method for converter dephosphorization and vanadium extraction, and a converter dephosphorization and vanadium extraction method, which discloses that sodium salt, scale, bauxite fine powder, and water are mixed to form a mixture, and after baking to remove moisture, a cold bonded pellet product is obtained.

[0005] However, the existing vanadium oxide production process requires the CaO content in vanadium slag to be less than 2.5%, which makes it impossible to add calcium oxide for dephosphorization during the vanadium extraction process of vanadium-containing hot metal in a converter, resulting in phosphorus in the hot metal entering the semi-steel, which is not conducive to the production of high-value-added clean steel. Because adding calcium for dephosphorization will obtain high-calcium and high-phosphorus vanadium slag, and vanadium and phosphorus are likely to combine into phosphovanadomolybdic acid and other phosphate precipitates during the leaching process, which hinders the precipitation of vanadium, greatly reduces the vanadium precipitation rate, and affects the quality of vanadium at the same time. The phosphorus concentration is controlled below 0.015 g / L during the sodium roasting and water leaching process. The phosphorus concentration is controlled below 0.06 g / L during the calcification roasting and acid leaching process. Currently, due to the high requirement for the phosphorus content in vanadium slag in the roasting and leaching process. Therefore, it is difficult to simultaneously extract vanadium and dephosphorize during the converter vanadium extraction process. Summary of the Invention

[0006] In view of this, the embodiments of the present invention disclose a method for increasing the vanadium content in converter vanadium slag, and propose synchronous vanadium extraction and dephosphorization in the converter. After that, the molten vanadium slag is prepared into magnetic vanadium spinel through selective oxidation, and further separation of the vanadium spinel from phosphorus and silicate phases is realized. The separated vanadium spinel has a low phosphorus content and a high vanadium content, which can avoid the problem of difficult dephosphorization in the later stage.

[0007] Some embodiments of the disclosed method for increasing the vanadium content in converter vanadium slag include the steps of:

[0008] S1. The vanadium-bearing hot metal is blown and smelted in a converter, and a dephosphorizing agent and a coolant are added during the smelting process to obtain molten vanadium slag and semi-steel; wherein, the content of each component in the vanadium-bearing hot metal is: C is 3.5 - 4.8 wt%, Si is 0.01 - 0.36 wt%, Ti is 0.01 - 0.32 wt%, P is 0.01 - 0.1 wt%, V is 0.05 - 0.5 wt%, Cr is 0 - 0.5 wt%; the P content in the semi-steel is lower than 0.003 wt%; the CaO content in the molten vanadium slag is greater than 5 wt%, and the P content is greater than 0.05 wt%;

[0009] S2. A material containing a high-valence oxide is added to the obtained molten vanadium slag, and CO 2 -O 2 gas is stirred, and the reaction is carried out at a set temperature; during the reaction, the reaction process is synergistically strengthened by ultrasonic, microwave and magnetic field to obtain a magnetic solid vanadium spinel and a molten liquid silicate mixture; the content of the magnetic solid vanadium spinel is 20 - 100 wt%;

[0010] S3. The magnetic solid vanadium spinel and the molten solid silicate mixture are separated under a magnetic field condition to obtain magnetic vanadium spinel and molten silicate respectively.

[0011] Further, some embodiments of the disclosed method for increasing the vanadium content in converter vanadium slag further include the steps of:

[0012] S4. The obtained molten liquid silicate is cooled and added to the converter as a coolant to realize the recycling of iron.

[0013] Some embodiments of the disclosed method for increasing the vanadium content in converter vanadium slag, the dephosphorizing agent includes one or a combination of more of CaO, CaCO 3 , Na 2 CO 3 , MgO, Al 2 O 3 , CaF 2 , and the coolant includes silicate.

[0014] Some embodiments of the disclosed method for increasing the vanadium content in converter vanadium slag, in step S2, the set temperature is 1000 - 1600 °C, CO2 -O 2 The flow rate of the gas is 0 - 12 m per ton of vanadium slag 3 , and the high-valence oxide materials include MnO 2 , Mn 2 O 3 , Fe 3 O 4 , Fe 2 VO 4 , CeO 2 , nanoscale core-shell structured Fe 2 O 3 @CeO 2 .

[0015] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, in step S3, the separation of the magnetic solid vanadium spinel and the molten liquid silicate mixture is achieved at a temperature of 1000 - 1600 °C.

[0016] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, the addition amount of the dephosphorizer is 10 - 40 kg per ton of vanadium-containing hot metal, and the addition amount of the coolant is 10 - 70 kg per ton of vanadium-containing hot metal.

[0017] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, in step S2, ultrasonic enhanced heating is adopted in the initial slag mixing stage, and the ultrasonic intensity is set to 20 - 40 kHz; microwave enhanced heating is adopted in the middle stage of the reaction, and the microwave frequency is set to 2.45 GHz; magnetic field enhanced reaction process is adopted in the later stage of the reaction, and the magnetic field intensity is set at 0.1 - 0.5 T.

[0018] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, the high-valence oxide materials are MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 ; or, MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 and CeO 2 ; or nanoscale core-shell structured Fe 2 O 3 @CeO 2 .

[0019] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, in step S3, the magnetic field intensity is set at 0.1 - 0.5 T.

[0020] The method for increasing the vanadium content in converter vanadium slag disclosed in the embodiments of the present invention has the following beneficial technical effects:

[0021] (1) Simultaneously achieve vanadium extraction and phosphorus removal to obtain vanadium slag. The phosphorus content in the semi-steel is lower than 0.003 wt%. The separation of vanadium spinel from the molten slag phase is initially achieved through a dephosphorizing agent. Subsequently, the spinel is transformed into magnetic vanadium spinel through selective oxidation, and further separation is achieved through magnetism. Through two-step slag adjustment, 95% of the phosphorus in apatite and spinel enters the silicate phase, and the phosphorus content in the obtained vanadium spinel is lower than 0.003 wt%.

[0022] (2) The vanadium slag obtained traditionally has a low V 2 O 5 content. The new method realizes directly obtaining magnetic vanadium spinel, which has a high vanadium content and a low silicon content.

[0023] (3) Adding the silicate obtained from the reaction as a coolant to the converter realizes the recycling of iron, greatly reducing the iron content in the tailing slag. The silicate phase is added to the vanadium extraction converter as a coolant to further recover the iron and vanadium in the silicate, reducing the iron and vanadium content in the tailing slag.

[0024] (4) Different from the traditional method of separating spinel and olivine in vanadium slag by high gravity, by transforming FeV 2 O 4 into Fe 2 VO 4 , the magnetic separation of magnetic vanadium spinel from molten silicate is realized.

[0025] (5) Compared with magnetic enrichment of vanadium in stone coal, the formation of magnetic substances in stone coal is obtained through solid-solid reaction. It is relatively easy to obtain Fe 2 O 3 and V 2 O 3 to Fe 2 VO 4 . The process of enriching vanadium in stone coal emphasizes avoiding sintering caused by too high temperature. Magnetic enrichment of stone coal separates magnetic substances and non-magnetic substances through ball milling at low temperature. The formation of magnetic substances in the new method is in liquid silicate, and magnetic substances are obtained through precipitation. The reaction mechanism and formation process are completely different; the separation process is simple and does not require additional processes such as ball milling; through vanadium extraction and phosphorus removal and magnetic separation, phosphorus remains in the silicate phase, and the enriched vanadium iron spinel is phosphorus-free and can be directly used for vanadium extraction.

[0026] (6) By regulating the composition and magnetism, the preferential precipitation of V 2 O 3 is achieved, and then Fe 2 VO 4Package V 2 O 3 , or add Fe 2 VO 4 and Fe 3 O 4 and other magnetic substances to wrap the precipitated V 2 O 3 , and realize magnetic separation to obtain a solid phase with high V 2 O 3 content; CeO 2 can be used as an oxidant or as a strengthening solid-phase magnetic substance to achieve separation.

[0027] (7), The appearance of the apatite phase leads to an increase in the phosphorus content in the spinel phase. By regulating the slag system with sodium carbonate, the apatite precipitated in the molten slag is converted into a molten liquid phase, and the phosphorus entering the molten liquid phase in the slag is regulated to reduce the phosphorus content in the spinel phase.

[0028] (8), Through the technical combination of multi-physical field enhanced reaction, high-temperature in-situ separation, and phosphorus directional recycling, solve the problems of low vanadium recovery rate, serious phosphorus pollution, and high energy consumption.

[0029] (9), Ultrasonic, microwave, and magnetic field multi-physical field synergistic regulation. The ultrasonic wave with a frequency of 20 - 40 kHz acts preferentially on the initial mixing stage of the molten slag to break the high-valent oxide particles; the microwave selectively heats FeV 2 O 4 in the middle stage of the reaction to promote the conversion to Fe 2 VO 4 ; the magnetic field guides the directional growth of vanadium spinel in the later stage of the reaction to promote the separation of vanadium and silicon; the obtained particle size is concentrated around 50 μm.

[0030] (10), The CO 2 -O 2 gas ratio is dynamically adjusted, and the CO 2 / O 2 ratio is adjusted in real time according to the molten slag temperature to avoid the overoxidation of vanadium to V 2 O 5 , and at the same time inhibit the excessive generation of Fe 3+ .

[0031] (11), Add a nano-scale Fe 2 O 3 @CeO 2 core-shell structure catalyst with a particle size of 20 - 50 nm. Utilize the oxygen vacancies of CeO 2 to promote the activation of CO 2 , reduce the activation energy of V 4+ conversion to V 3+ , shorten the reaction time by 30%, and increase the vanadium recovery rate to over 95%. Specific implementation method

[0032] As used herein, the term "embodiment" refers to any embodiment described as "exemplary", and such an embodiment need not be construed as superior to or better than other embodiments. For the performance index tests in the embodiments of the present invention, unless otherwise specified, conventional test methods in the art are adopted. It should be understood that the terms described in the embodiments of the present invention are only used to describe specific embodiments and are not intended to limit the content disclosed in the embodiments of the present invention.

[0033] Unless otherwise specified, the technical and scientific terms used herein have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the embodiments of the present invention belong; other test methods and technical means not specifically noted in the embodiments of the present invention refer to the experimental methods and technical means commonly adopted by those of ordinary skill in the art.

[0034] The terms "substantially" and "about" as used herein are used to describe minor fluctuations. For example, they can refer to less than or equal to ±5%, such as less than or equal to ±2%, such as less than or equal to ±1%, such as less than or equal to ±0.5%, such as less than or equal to ±0.2%, such as less than or equal to ±0.1%, such as less than or equal to ±0.05%. Numerical data presented or represented in a range format herein is used only for convenience and brevity and should therefore be flexibly interpreted as including not only the explicitly listed values that are the bounds of the range, but also all individual values or sub-ranges included within that range. For example, the numerical range of "1 to 5%" should be interpreted as including not only the explicitly listed values of 1% to 5%, but also the individual values and sub-ranges within the indicated range. Thus, within this numerical range, individual values such as 2%, 3.5%, and 4% are included, as well as sub-ranges such as 1% to 3%, 2% to 4%, and 3% to 5%, etc. This principle also applies to ranges that list only one numerical value. In addition, such an interpretation applies regardless of the width of the range or the characteristics described.

[0035] In this document, including in the claims, conjunctions such as "comprising", "including", "carrying", "having", "containing", "involving", "accommodating", etc. are understood to be open-ended, that is, meaning "including but not limited to". Only the conjunctions "consisting of" and "composed of" are closed conjunctions.

[0036] To better illustrate the content of the present invention, numerous specific details are given in the following specific embodiments. Those skilled in the art should understand that the present invention can be implemented without some specific details. In the embodiments, some methods, means, instruments, devices, etc. well-known to those skilled in the art are not described in detail in order to highlight the gist of the present invention.

[0037] On the premise of no conflict, the technical features disclosed in the embodiments of the present invention can be arbitrarily combined, and the obtained technical solutions belong to the content disclosed in the embodiments of the present invention.

[0038] In some embodiments, the method for increasing the vanadium content in converter vanadium slag includes the steps of:

[0039] S1. The vanadium-bearing hot metal is blown with oxygen in a converter, and a dephosphorizer and a coolant are added during the smelting process to obtain molten vanadium slag and semi-steel; wherein, by mass, the content of each component in the vanadium-bearing hot metal is: C is 3.5-4.8%, Si is 0.01-0.36%, Ti is 0.01-0.32%, P is 0.01-0.1%, V is 0.05-0.5%, Cr is 0-0.5%; the P content in the semi-steel is less than 0.003%; the CaO content in the molten vanadium slag is greater than 5%, and the P content is greater than 0.05%;

[0040] Generally, the dephosphorizer is used to remove phosphorus in the vanadium-bearing hot metal, convert phosphorus into apatite and spinel, and regulate the converted apatite and spinel in the silicate phase; generally, the addition amount of the dephosphorizer is 10-40 kg per ton of vanadium-bearing hot metal; the coolant does not participate in the reaction and is used to reduce the temperature of the reaction melt to increase the oxidation rate of vanadium. Generally, the addition amount of the coolant is 10-70 kg per ton of vanadium-bearing hot metal;

[0041] S2. A high-valent oxide material is added to the obtained molten vanadium slag, and CO 2 -O 2 gas is stirred, and the reaction is carried out at a set temperature to obtain a magnetic solid vanadium spinel and a molten liquid silicate mixture; the content of magnetic vanadium spinel in the mixture is 20-100 wt%;

[0042] Generally, the obtained magnetic vanadium spinel contains the following components: 20-45 wt% V 2 O 3 、0-11 wt% Cr 2 O 3 、0.5-5 wt% SiO 2 、0-0.08 wt% P、20-45 wt% FeO、6-12 wt% MnO、8-12 wt% TiO 2 ;

[0043] The molten silicate contains the following components: 27-35 wt% SiO 2 、8-15 wt% TiO 2 、4-20 wt% CaO;

[0044] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under a magnetic field condition to obtain magnetic vanadium spinel and molten silicate respectively. Generally, the magnetic field strength is set at 0.1 - 0.5 T;

[0045] S4. The obtained molten silicate is cooled and added to the converter as a coolant to realize the recycling of iron. Usually, the TFe content in the tail slag obtained by the method disclosed in the embodiments of the present invention can be reduced by more than 30 wt% compared with the TFe content in the traditional process.

[0046] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, the dephosphorizer includes one or a combination of more of CaO, CaCO 3 , Na 2 CO 3 , MgO, Al 2 O 3 , CaF 2 , and the coolant includes silicate.

[0047] For the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, in step S2, the set temperature is 1000 - 1600 °C, the flow rate of CO 2 -O 2 gas is 0 - 12 m 3 per ton of vanadium slag, and the high-valence oxide-containing material includes MnO 2 , Mn 2 O 3 , Fe 3 O 4 , Fe 2 VO 4 or CeO 2 . Among them, MnO 2 , Mn 2 O 3 has an oxidizing effect, Fe 3 O 4 , Fe 2 VO 4 , CeO 2 has the effect of enhancing magnetism; the nanoscale core-shell structure Fe 2 O 3 @CeO 2 has both oxidizing and magnetism-enhancing effects.

[0048] In some embodiments, the high-valence oxide-containing material is more preferably a combination of MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 . For example, MnO 2, Fe 3 O 4 combination, or Mn 2 O 3 , Fe 2 VO 4 combination. Generally, in the combination of MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 , the mass ratio of the two is 4 - 6:4 - 6.

[0049] In some embodiments, the material containing higher - valence oxides is further preferably a combination of MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 and CeO 2 . For example, a combination of MnO 2 , Fe 3 O 4 , CeO 2 , or a combination of MnO 2、 Fe 2 VO 4 , CeO 2 . Generally, in the combination of MnO 2 or Mn 2 O 3 , Fe 3 O 4 or Fe 2 VO 4 and CeO 2 , the mass ratio of the three is 3 - 5:3 - 4:1 - 2 in sequence.

[0050] Furthermore, in some embodiments, the material containing higher - valence oxides is more preferably nanoscale core - shell structured Fe 2 O 3 @CeO 2 .

[0051] In the method for increasing the vanadium content in converter vanadium slag disclosed in some embodiments, in step S3, the mixture of magnetic solid - state vanadium spinel and molten silicate is separated at a temperature of 1000 - 1600 °C.

[0052] The following further exemplarily illustrates the technical details in combination with embodiments.

[0053] Example 1

[0054] In Example 1, the method for increasing the vanadium content in converter vanadium slag comprises:

[0055] S1. Smelting vanadium-containing molten iron (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, and Cr is 0.2%) in a converter by oxygen blowing, adding a dephosphorizing agent and a coolant during the smelting process to obtain molten vanadium slag and semi-steel; wherein, the vanadium-containing molten iron is 200 tons, the oxygen blowing smelting temperature is 1290° C., the oxygen blowing smelting time is 5 minutes, the dephosphorizing agent CaO is 5 tons, and the coolant silicate is 10 tons;

[0056] S2, add 0.01t of MnO to the obtained molten vanadium slag 2 , CO 2 -O 2 The gas is stirred and heated to a set temperature to react to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 CO in gas 2 With O 2 The ratio is 10:1, and the total flow is 50m 3 , reaction time 10min, set temperature 1350℃;

[0057] S3, the magnetic solid vanadium spinel and the molten liquid silicate mixture are separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively, and the molten liquid silicate is poured out to obtain solid Fe 2 VO 4 Phase. Among them, the magnetic field strength is 0.2T.

[0058] Example 2

[0059] In Example 2, the method for increasing the vanadium content in converter vanadium slag comprises:

[0060] S1. Smelting vanadium-containing molten iron (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, and Cr is 0.2%) in a converter by oxygen blowing, adding a dephosphorizing agent and a coolant during the smelting process to obtain molten vanadium slag and semi-steel; wherein, the vanadium-containing molten iron is 200 tons, the oxygen blowing smelting temperature is 1290° C., the oxygen blowing smelting time is 5 minutes, the dephosphorizing agent CaO is 5 tons, and the coolant silicate is 10 tons;

[0061] S2, add 0.01t of Mn to the obtained molten vanadium slag 2 O 3 , CO 2 -O 2 The gas is stirred and heated to a set temperature to react to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO2 -O 2 CO in the gas 2 and O 2 The ratio is 10:1, the total flow rate is 50 m 3 , the reaction time is 10 min, and the set temperature is 1350 °C;

[0062] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.5 T.

[0063] Example 3

[0064] In Example 3, the method for increasing the vanadium content in converter vanadium slag includes:

[0065] S1. Vanadium-bearing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, Cr is 0.2%) is blown with oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel; among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0066] S2. 0.01 t of Fe 3 O 4 is added to the obtained molten vanadium slag, and CO 2 -O 2 gas is stirred, heated to the set temperature for reaction to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 In the gas, the ratio of CO 2 to O 2 is 10:1, the total flow rate is 50 m 3 , the reaction time is 10 min, and the set temperature is 1350 °C;

[0067] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0068] Example 4

[0069] In Example 4, the method for increasing the vanadium content in converter vanadium slag includes:

[0070] S1. Vanadium-bearing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, and V is 0.35%) is blown with oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel. Among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0071] S2. 0.06 t of Fe 2 VO 4 and 0.04 t of Mn 2 O 3， are introduced into the obtained molten vanadium slag, and CO 2 -O 2 gas is used for stirring. It is heated to the set temperature for reaction, and ultrasound is introduced during the initial stage of stirring. The ultrasound intensity is set to 200 kHz to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate. The ratio of CO 2 -O 2 in the gas is 10:1, the total flow rate is 50 m 2 with O 2 , the reaction time is 6 min, and the set temperature is 1350 °C; 3

[0072] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under a magnetic field condition to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain a solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0073] Example 5

[0074] In Example 5, the method for increasing the vanadium content in converter vanadium slag includes:

[0075] S1. Vanadium-bearing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, and V is 0.35%) is blown with oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel. Among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0076] S2. Add 0.05 t of Fe to the obtained molten vanadium slag. 2 VO 4 and 0.05 t of MnO 2 , introduce CO 2 -O 2 gas for stirring, heat to the set temperature for reaction, apply a magnetic field during the later stage of the reaction, set the magnetic field strength at 0.1 T, and obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 The ratio of CO 2 to O 2 in the gas is 10:1, the total flow rate is 50 m 3 , the reaction time is 5 min, and the set temperature is 1350 °C.

[0077] S3. Separate the mixture of magnetic solid vanadium spinel and molten liquid silicate under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. Pour out the molten liquid silicate to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0078] Example 6

[0079] In Example 6, the method for increasing the vanadium content in converter vanadium slag includes:

[0080] S1. The vanadium-containing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%) is blown with oxygen in a converter. During the smelting process, a dephosphorizer and a coolant are added to obtain molten vanadium slag and semi-steel; among them, the vanadium-containing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, the dephosphorizer Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0081] S2. Add 0.04 t of Fe 2 VO 4 , 0.04 t of MnO 2 and 0.01 t of CeO 2 to the obtained molten vanadium slag, introduce CO 2 -O 2 gas for stirring, heat to the set temperature for reaction for 2 min, and then react for 5 min under magnetic conditions to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 The ratio of CO 2 to O 2 in the gas is 10:1, the total flow rate is 50 m 3, the reaction time is 5 min, and the set temperature is 1350 °C;

[0082] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under a magnetic field condition to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0083] Example 7

[0084] In Example 7, the method for increasing the vanadium content in converter vanadium slag includes:

[0085] S1. Vanadium-bearing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, and V is 0.35%) is blown and smelted with oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel; among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0086] S2. In the obtained molten vanadium slag, 0.01 t of Fe 2 O 3 @CeO 2 core-shell structure catalyst with a particle size of 20 nm is introduced, and CO 2 -O 2 gas is stirred, heated to the set temperature and reacted for 2 min, and then reacted for 5 min under magnetic conditions to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 in the gas, the ratio of CO 2 to O 2 is 10:1, and the total flow rate is 50 m 3 , the reaction time is 5 min, and the set temperature is 1350 °C;

[0087] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under a magnetic field condition to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0088] Example 8

[0089] In Example 8, the method for increasing the vanadium content in converter vanadium slag includes:

[0090] S1. Vanadium-containing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, Cr is 0.2%) is smelted by blowing oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel. Among them, the vanadium-containing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0091] S2. In the obtained molten vanadium slag, 0.04 t of Fe 2 VO 4 , 0.04 t of MnO 2 and 0.02 t of CeO 2 are added, and CO 2 -O 2 gas is introduced for stirring, heated to a set temperature and reacted for 2 min, and then reacted for 5 min under magnetic conditions to obtain a magnetic solid vanadium spinel and a molten liquid silicate mixture. The ratio of CO 2 -O 2 in the gas is 10:1, the total flow rate is 50 m 2 and O 2 is 10:1, the total flow rate is 50 m 3 , the reaction time is 5 min, and the set temperature is 1350 °C;

[0092] S3. The magnetic solid vanadium spinel and the molten liquid silicate mixture are separated under magnetic field conditions to obtain a magnetic solid vanadium spinel and a molten liquid silicate respectively. The molten liquid silicate is poured out to obtain a solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0093] Example 9

[0094] In Example 9, the method for increasing the vanadium content in converter vanadium slag includes:

[0095] S1. Vanadium-containing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, Cr is 0.2%) is smelted by blowing oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel. Among them, the vanadium-containing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t;

[0096] S2. In the obtained molten vanadium slag, 0.04 t of Fe 2 VO4 , 0.04 t of MnO 2 and 0.02 t of CeO 2 , and introduce CO 2 -O 2 gas for stirring, heat to the set temperature and react for 2 min, then react for 5 min under magnetic conditions to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 In the gas, the ratio of CO 2 to O 2 is 10:1, the total flow rate is 50 m 3 , the reaction time is 5 min, and the set temperature is 1350 °C;

[0097] S3. Separate the mixture of magnetic solid vanadium spinel and molten liquid silicate under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. Pour out the molten liquid silicate to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0098] Example 10

[0099] In Example 10, the method for increasing the vanadium content in converter vanadium slag includes:

[0100] S1. The vanadium-bearing hot metal (wherein, by mass, C is 4.4%, Si is 0.2%, Ti is 0.2%, P is 0.05%, V is 0.35%, Cr is 0.2%) is blown with oxygen in a converter. During the smelting process, a dephosphorizing agent and a coolant are added to obtain molten vanadium slag and semi-steel; among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, the dephosphorizing agent is Na 2 CO 3 5 t, and the coolant is 10 t of silicate;

[0101] S2. In the obtained molten vanadium slag, add 0.01 t of Fe 2 O 3 @CeO 2 core-shell structure with a particle size of 30 nm; introduce CO 2 -O 2 gas for stirring, introduce ultrasound in the first 2 min when heating to the set temperature, introduce microwave after 2 min, and then add a magnetic field for 2 min to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 In the gas, the ratio of CO 2 to O 2 is 10:1, the total flow rate is 50 m 3, the reaction time is 5 min, and the set temperature is 1350 °C;

[0102] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0103] Comparative Example 1

[0104] In Comparative Example 1, the treatment method of vanadium slag includes:

[0105] S1. The vanadium-bearing hot metal is blown with oxygen in a converter, and a dephosphorizing agent and a coolant are added during the smelting process to obtain molten vanadium slag and semi-steel; among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, and the dephosphorizing agent Na 2 CO 3 is 5 t, and the coolant silicate is 10 t.

[0106] Comparative Example 2

[0107] In Comparative Example 2, the treatment method of vanadium slag includes:

[0108] S1. The vanadium-bearing hot metal is blown with oxygen in a converter, and a dephosphorizing agent and a coolant are added during the smelting process to obtain molten vanadium slag and semi-steel; among them, the vanadium-bearing hot metal is 200 t, the oxygen-blowing smelting temperature is 1290 °C, the oxygen-blowing smelting time is 5 minutes, the dephosphorizing agent CaO is 5 t, and the coolant silicate is 10 t;

[0109] S2. In the obtained molten vanadium slag, CO 2 -O 2 gas is stirred, heated to the set temperature for reaction to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; CO 2 -O 2 in the gas, the ratio of CO 2 to O 2 is 10:1, the total flow rate is 50 m 3 , the reaction time is 10 min, and the set temperature is 1350 °C;

[0110] S3. The mixture of magnetic solid vanadium spinel and molten liquid silicate is separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively. The molten liquid silicate is poured out to obtain solid Fe 2 VO 4 phase. Among them, the magnetic field strength is 0.2 T.

[0111] The list of the main components of the vanadium slag obtained in Examples 1 to 10 and Comparative Examples 1 to 2 is shown in Table 1;

[0112] Table 1 List of Main Components of Vanadium Slag

[0113]

[0114]

[0115] From the data listed in Table 1, it can be seen that in the vanadium slag obtained in Examples 1 to 3, the content of V 2 O 3 and Cr 2 O 3 in the spinel phase can reach 27 wt.% and 11 wt.%, which are much higher than the content of vanadium slag in Comparative Examples 1 to 2. At the same time, the content of SiO 2 decreases, and the content of P is lower than 0.003 wt.%; in Examples 4 to 8, the content of V 2 O 3 and Cr 2 O 3 in the spinel phase can reach 42 wt.%, which is much higher than the content in Comparative Examples 1 to 2. The content of Cr 2 O 3、 SiO 2 and P is zero; in Examples 9 to 10, the content of V 2 O 3 and Cr 2 O 3 can reach 50 wt.%, which is much higher than the content in Comparative Examples 1 to 2. The content of Cr 2 O 3 can reach 12 wt.%, and the content of SiO 2 and P is zero.

[0116] The method for increasing the vanadium content in converter vanadium slag disclosed in the embodiments of the present invention initially separates vanadium spinel from the molten slag phase through a dephosphorizing agent, and then transforms the spinel into magnetic vanadium spinel through selective oxidation and further separates it by magnetism. The obtained vanadium spinel has a phosphorus content lower than 0.003 wt%; the obtained magnetic vanadium spinel has a high vanadium content and a low phosphorus content; the silicate obtained by the reaction is added to the converter as a coolant to realize the recycling of iron, greatly reducing the iron content in the tail slag; through vanadium extraction and dephosphorization and magnetic separation, phosphorus remains in the silicate phase, while the enriched vanadium iron spinel is phosphorus-free and can be directly used for vanadium extraction; the separated silicate phase is added to the vanadium extraction converter as a coolant to further recover iron and vanadium in the silicate, reducing the iron and vanadium content in the tail slag.

[0117] The technical solutions disclosed in the embodiments of the present invention and the technical details disclosed in the embodiments are only illustrative of the inventive concept of the present invention and do not constitute a limitation on the technical solutions of the embodiments of the present invention. Any conventional changes, substitutions, combinations, etc. made to the technical details disclosed in the embodiments of the present invention have the same inventive concept as the present invention and are within the scope of protection of the claims of the present invention.

Claims

1. A method for increasing the vanadium content in converter vanadium slag, characterized in that: Includes steps: S1. Smelting vanadium-containing molten iron with oxygen in a converter, adding a dephosphorizing agent and a coolant during the smelting process, and obtaining molten vanadium slag and semi-steel; wherein the mass content of each component in the vanadium-containing molten iron is: C is 3.5-4.8wt%, Si is 0.01-0.36wt%, Ti is 0.01-0.32wt%, P is 0.01-0.1wt%, V is 0.05-0.5wt%, Cr is 0-0.5wt%; the P content in the semi-steel is less than 0.003wt%; the CaO content in the molten vanadium slag is greater than 5wt%, and the P content is greater than 0.05wt%; S2, adding high-valent oxide materials to the obtained molten vanadium slag, introducing CO2-O2 gas for stirring, and reacting at a set temperature; during the reaction, using ultrasound, microwaves and magnetic fields to synergistically strengthen the reaction process to obtain a mixture of magnetic solid vanadium spinel and molten liquid silicate; the content of the magnetic solid vanadium spinel is 20-100wt%; S3. The magnetic solid vanadium spinel and the molten liquid silicate mixture are separated under magnetic field conditions to obtain magnetic solid vanadium spinel and molten liquid silicate respectively.

2. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: Also includes the steps: S4. The obtained molten liquid silicate is cooled and added to the converter as a coolant to achieve iron recovery.

3. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: The dephosphorizing agent includes one or a combination of CaO, CaCO3, Na2CO3, MgO, Al2O3, and CaF2, and the coolant includes silicate.

4. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: In step S2, the temperature is set to 1000-1600°C, and the flow rate of CO2-O2 gas is 0-12m / ton of vanadium slag. 3 , materials containing high-valent oxides include MnO2, Mn2O3, Fe3O4, Fe2VO4, CeO2, and nanoscale core-shell structure Fe2O3@CeO2.

5. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: In step S3, the magnetic solid vanadium spinel and the molten liquid silicate mixture are separated at a temperature of 1000-1600°C.

6. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: The amount of dephosphorizing agent added is 10-40 kg / ton of vanadium-containing molten iron, and the amount of coolant added is 10-70 kg / ton of vanadium-containing molten iron.

7. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: In step S2, ultrasonic enhanced heating is used in the initial mixing stage of the slag, and the ultrasonic intensity is set to 20-40 kHz; microwave enhanced heating is used in the middle stage of the reaction, and the microwave frequency is set to 2.45 GHz; and magnetic field is used to enhance the reaction process in the late stage of the reaction, and the magnetic field intensity is set to 0.1-0.5T.

8. The method for increasing the vanadium content in converter vanadium slag according to claim 1, characterized in that: In step S3, the magnetic field strength is set at 0.1-0.5T.

9. The method for increasing the vanadium content in converter vanadium slag according to claim 4, characterized in that: The high-valent oxide material is a combination of MnO2 or Mn2O3, Fe3O4 or Fe2VO4; or a combination of MnO2 or Mn2O3, Fe3O4 or Fe2VO4 and CeO2; or a nano-scale core-shell structure Fe2O3@CeO2.

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