Vanadium-titanium magnetite deep reduction electric furnace and smelting method thereof

Abstract

The application discloses a vanadium-titanium magnetite deep reduction electric furnace, which comprises an electric furnace body, an internal space of the electric furnace body is divided into an electric furnace front end and an electric furnace rear end, a front end electrode and a front end feeding port are arranged on the upper portion of the electric furnace front end, a rear end electrode and a rear end feeding port are arranged on the upper portion of the electric furnace rear end, a slag-iron port and a tapping hole are arranged on the side surface of the electric furnace rear end, the slag-iron port is located above the tapping hole, and the part of the furnace bottom of the electric furnace front end, which is far away from the electric furnace rear end, is higher than the part of the furnace bottom of the electric furnace front end, which is close to the electric furnace rear end, so that liquid-phase substances generated in the electric furnace front end can flow to the electric furnace rear end naturally, the physical separation of the submerged-arc smelting process and the open-arc smelting process in the metallization pellet electric furnace deep reduction process of vanadium-titanium magnetite can be realized, the continuous feeding and discharging of the vanadium-titanium magnetite metallization pellets and the continuous slag-iron tapping can be realized, and the production efficiency of the electric furnace deep reduction process is improved. The application further discloses a smelting method for vanadium-titanium magnetite deep reduction.

Description

Technical Field

[0001] This invention belongs to the field of non-blast furnace ironmaking technology, and in particular relates to a deep reduction electric furnace for vanadium-titanium magnetite and its smelting method. Background Technology

[0002] Vanadium-titanium magnetite contains three valuable elements: iron, vanadium, and titanium. The existing gas-based vertical shaft furnace-electric furnace deep reduction process can obtain vanadium-containing molten iron and high-titanium slag, representing a green production process that efficiently and comprehensively recovers these elements. However, during the deep reduction process of vanadium-titanium magnetite metallized pellets in the electric furnace, as smelting time progresses, the metallized pellets near the electrodes first melt to form small molten pools. These small pools then connect to form a large molten pool, and finally, all materials melt to form vanadium-containing molten iron and high-titanium slag. During this process, as smelting progresses, the metallized pellets continuously melt, the TiO2 content in the molten pool gradually increases, the molten pool temperature also rises, and the resistivity of the furnace charge continuously decreases. This necessitates constant adjustment of the electrodes to prevent excessive current from causing electrode breakage. The operation is quite difficult and requires a high level of control over the electric furnace. Therefore, this type of electric furnace smelting process is a periodic cyclical smelting. That is, after charging, the electrodes first undergo submerged arc smelting. After smelting to a certain extent, the conductivity of the furnace charge increases (the current increases), and the electrodes need to be slowly raised (to prevent excessive current from causing electrode breakage) until the electrodes are lifted away from the furnace charge. Then, open arc smelting is carried out. After smelting is completed, the slag and iron are discharged, and the above steps are repeated. It can be seen that this smelting process can only be periodic, for example, divided into four steps. After the fourth step is completed, the slag and iron are discharged, and then the process starts again from the first step. It can be seen that the efficiency of this intermittent smelting is relatively low. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a deep reduction electric furnace for vanadium-titanium magnetite and its smelting method. This furnace achieves physical separation of submerged arc smelting and open arc smelting processes during the deep reduction of vanadium-titanium magnetite metallized pellets. The furnace employs submerged arc smelting in the front section for melting the metallized pellets, and open arc smelting in the rear section for deep reduction of the liquid-phase charge and slag-iron separation. Simultaneously, it enables continuous feeding and discharging of vanadium-titanium magnetite metallized pellets and continuous slag-iron discharge, thereby improving the production efficiency of the deep reduction process, reducing the difficulty of deep reduction smelting, enhancing the heat utilization rate within the furnace, and reducing power consumption during the deep reduction process.

[0004] The present invention provides a deep reduction electric furnace for vanadium-titanium magnetite, comprising:

[0005] The electric furnace body has its internal space divided into the front end and the rear end of the electric furnace.

[0006] The front electrode and the front feed inlet are located at the upper part of the front end of the electric furnace;

[0007] The rear electrode and the rear feed inlet are located at the upper part of the rear end of the electric furnace;

[0008] The slag and iron tapping spout and the iron tapping spout are located on the side of the rear end of the electric furnace, with the slag and iron tapping spout located above the iron tapping spout;

[0009] The portion of the furnace bottom at the front end of the electric furnace that is farther from the rear end of the electric furnace is higher than the portion near the rear end of the electric furnace, so as to allow the liquid phase material generated at the front end of the electric furnace to flow naturally to the rear end of the electric furnace.

[0010] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the furnace bottom at the front end of the furnace includes a slope with a preset angle, the slope gradually descending from the front end of the furnace to the rear end of the furnace, the preset angle being used to allow the liquid phase material generated at the front end of the furnace to flow naturally to the rear end of the furnace, and the preset angle being smaller than the angle of repose and angle of accumulation of the solid furnace charge.

[0011] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, there is only one slope, and the part of the slope furthest from the rear end of the electric furnace is the highest, while the part closest to the rear end of the electric furnace is the lowest.

[0012] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the furnace bottom at the rear end of the furnace is a horizontal plane, and the part of the slope closest to the rear end of the furnace is at the same height as the furnace bottom at the rear end of the furnace.

[0013] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the preset tilt angle is 3° to 7°.

[0014] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the front electrode is used to be embedded in the furnace charge for submerged arc smelting, and the height of the front electrode is 30 cm to 50 cm above the upper edge of the slag-iron taphole.

[0015] The front feed port is located around the front electrode and is used for feeding metallized pellets and carbonaceous reducing agent.

[0016] Preferably, in the above-mentioned vanadium-titanium magnetite deep reduction electric furnace, the rear electrode is used for open-arc smelting of liquid-phase deep reduction, and it is also connected to a height control device. The height control device includes a central control component, a lifting component and a slag-iron liquid level recognition component, all of which are communicatively connected to the central control component. The central control component is used to control the lifting component to drive the rear electrode to perform corresponding lifting operations according to the slag-iron liquid level height recognized by the slag-iron liquid level recognition component, so that the rear electrode is always located between 15 cm and 25 cm above the slag-iron liquid level and does not exceed the height of the front electrode.

[0017] The rear feed inlet is located around the rear electrode and is used for the addition of carbonaceous reducing agent and / or slagging agent during deep reduction smelting.

[0018] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the lower edge of the tap hole is 5 to 10 centimeters away from the furnace bottom at the rear end of the electric furnace, and the tap hole gradually rises along the direction from the inner side wall to the outer side wall at the rear end of the electric furnace.

[0019] Preferably, in the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the centerline of the slag-iron taphole is 20 to 50 centimeters higher than the horizontal centerline of the taphole on the inner sidewall at the rear end of the electric furnace.

[0020] This invention provides a smelting method for deep reduction of vanadium-titanium magnetite, utilizing an electric furnace for deep reduction of titanium magnetite as described in any of the above claims, comprising:

[0021] S1: Place the front electrode and the rear electrode in the working position, and fill the furnace body with inert gas until the content of the inert gas is not less than 99%;

[0022] S2: When starting the furnace, add a mixed charge of carbonaceous reducing agent and metallized pellets from the front feed port;

[0023] S3: Turn on the front electrode. The liquid phase material generated by the melting of the metallized pellets flows naturally to the rear end of the electric furnace until the liquid level at the rear end of the electric furnace reaches 20 cm to 30 cm. Then, adjust the height of the rear electrode to 15 cm to 25 cm above the liquid surface and turn on the rear electrode. At the same time, add carbonaceous reducing agent at the rear feed inlet.

[0024] S4: During the smelting process, when the pressure inside the electric furnace body rises to 0.3MPa to 0.4MPa, the venting valve is opened in a timely manner to release pressure so that the pressure inside the electric furnace body is maintained within the preset pressure range;

[0025] S5: As the liquid level in the rear end of the electric furnace rises, the rear electrode is continuously raised until it reaches the same height as the front electrode, opening the slag and iron outlet until the slag or slag and iron are discharged. At the same time, the rear electrode is controlled to be at a suitable working height to seal the slag and iron outlet.

[0026] S6: Add carbonaceous reducing agent and metallized pellets to the front end of the electric furnace, and add furnace charge in a timely and appropriate manner according to the material height in the front end of the electric furnace;

[0027] S7: Open the tap hole to discharge the molten iron under the slag tap, and at the same time control the rear electrode to be at a suitable working height. After the iron discharge is completed, seal the tap hole.

[0028] S8: Based on the liquid level at the rear end of the electric furnace and the charge height at the front end of the electric furnace, repeat steps S5, S6 and S7 to maintain the pressure inside the electric furnace body at 0.3MPa to 0.4MPa.

[0029] As described above, the vanadium-titanium magnetite deep reduction electric furnace provided by the present invention includes a furnace body, with its internal space divided into a furnace front end and a furnace rear end. The front electrode and front feed inlet are located at the upper part of the furnace front end; the rear electrode and rear feed inlet are located at the upper part of the furnace rear end; the slag-iron tap and the tapping port are located on the side of the furnace rear end, with the slag-iron tap located above the tapping port. The portion of the furnace bottom at the furnace front end that is farther from the furnace rear end is higher than the portion near the furnace rear end, allowing the liquid phase material generated at the furnace front end to flow naturally to the furnace rear end. This, therefore, facilitates the burial of metallized pellets. The liquefaction process of submerged arc smelting and the deep reduction process of open arc smelting are carried out in separate sections, optimizing the deep reduction process of vanadium-titanium magnetite metallized pellets. Therefore, it is possible to physically separate the submerged arc smelting and open arc smelting processes in the deep reduction of vanadium-titanium magnetite metallized pellets in an electric furnace. The front section of the electric furnace is submerged arc smelting for melting the metallized pellets, while the rear section is open arc smelting for deep reduction of the liquid-phase charge and slag-iron separation. Simultaneously, it achieves continuous feeding and discharging of vanadium-titanium magnetite metallized pellets and continuous slag-iron discharge, improving the production efficiency of the electric furnace deep reduction process, reducing the difficulty of electric furnace deep reduction smelting, and helping to improve the heat utilization rate within the electric furnace and reduce the power consumption of the deep reduction process. The vanadium-titanium magnetite deep reduction smelting method provided by this invention has the same advantages. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of an embodiment of a deep reduction electric furnace for vanadium-titanium magnetite provided by the present invention;

[0032] Figure 2 A schematic diagram of the control structure of another specific embodiment of a deep reduction electric furnace for vanadium-titanium magnetite;

[0033] Figure 3 This is a schematic diagram of an embodiment of a deep reduction smelting method for vanadium-titanium magnetite provided by the present invention. Detailed Implementation

[0034] The core of this invention is to provide a deep reduction electric furnace for vanadium-titanium magnetite and its smelting method. This method enables the physical separation of submerged arc smelting and open arc smelting processes during the deep reduction of vanadium-titanium magnetite metallized pellets in an electric furnace. The front section of the furnace is submerged arc smelting for melting the metallized pellets, while the rear section is open arc smelting for deep reduction of the liquid phase charge and slag-iron separation. Simultaneously, it achieves continuous feeding and discharging of vanadium-titanium magnetite metallized pellets and continuous slag-iron discharge, thereby improving the production efficiency of the deep reduction process, reducing the difficulty of deep reduction smelting, improving the heat utilization rate within the furnace, and reducing the power consumption of the deep reduction process.

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] An embodiment of the deep reduction electric furnace for vanadium-titanium magnetite provided by the present invention is as follows: Figure 1 As shown, Figure 1 This is a schematic diagram of an embodiment of a vanadium-titanium magnetite deep reduction electric furnace provided by the present invention. The vanadium-titanium magnetite deep reduction electric furnace may include:

[0037] The electric furnace body 1 can be rectangular in shape, and its internal space is divided into the front end 11 and the rear end 12. Specifically, the front end of the electric furnace can account for one-half to two-thirds of the length of the electric furnace, the length of the electric furnace is 4 to 7 times the height of the electric furnace, and the width of the electric furnace is determined according to actual needs.

[0038] The front electrode 111 and the front feed port 112 are located on the upper part of the front end 11 of the electric furnace, and the front feed port 112 can surround the outer periphery of the front electrode 111.

[0039] The rear electrode 121 and the rear feed port 122 are located at the upper part of the rear end 12 of the electric furnace, and the rear feed port 122 can surround the outer periphery of the rear electrode 121.

[0040] The slag and iron tapping spout 123 and the iron tapping spout 124 are located on the side of the rear end 12 of the electric furnace. The slag and iron tapping spout 123 is located above the iron tapping spout 124. The slag and iron tapping spout 123 is used to discharge slag and iron, and the iron tapping spout 124 is used to discharge molten iron.

[0041] The part of the furnace bottom at the front end 11 that is far from the rear end 12 is higher than the part that is near the rear end 12. The specific configuration is not limited. For example, it can be a sloping structure, a multi-stage stepped structure, or a combination of sloping and stepped structures, etc. It is used to allow the liquid phase material generated at the front end 11 to flow naturally to the rear end 12. In other words, the height difference can be used to allow the liquid phase material to flow naturally under the action of gravity from the part of the furnace bottom at the front end 11 that is far from the rear end 12 to the part of the furnace bottom at the front end 11 that is near the rear end 12, and finally reach the rear end 12. This keeps the front end 11 in a submerged arc smelting working state, while keeping the rear end 12 in a liquid phase deep reduction open arc smelting working state.

[0042] As described above, in the embodiment of the deep reduction electric furnace for vanadium-titanium magnetite provided by the present invention, the internal space is divided into a furnace front end and a furnace rear end, including the furnace body. The front electrode and the front feed inlet are located at the upper part of the furnace front end; the rear electrode and the rear feed inlet are located at the upper part of the furnace rear end; the slag-iron tap and the tapping port are located on the side of the furnace rear end, with the slag-iron tap located above the tapping port; the part of the furnace bottom at the furnace front end that is farther from the furnace rear end is higher than the part that is closer to the furnace rear end, allowing the liquid phase material generated at the furnace front end to flow naturally to the furnace rear end. This facilitates the liquefaction process of the submerged arc smelting of metallized pellets. The deep reduction process of vanadium-titanium magnetite metallization pellets is carried out in separate sections, optimizing the deep reduction process of vanadium-titanium magnetite metallization pellets. Therefore, it is possible to physically separate the submerged arc smelting and open arc smelting processes in the deep reduction process of vanadium-titanium magnetite metallization pellets in electric furnaces. The front section of the electric furnace is submerged arc smelting for melting metallization pellets, and the rear section is open arc smelting for deep reduction of liquid phase furnace charge and slag-iron separation. At the same time, it enables continuous feeding and discharging of vanadium-titanium magnetite metallization pellets and continuous slag-iron discharge, improving the production efficiency of the electric furnace deep reduction process, reducing the difficulty of electric furnace deep reduction smelting, helping to improve the heat utilization rate in the electric furnace, and reducing the power consumption of the electric furnace deep reduction process.

[0043] In a specific embodiment of the aforementioned deep reduction electric furnace for vanadium-titanium magnetite, the furnace bottom of the furnace front end 11 includes a ramp with a preset inclination angle. The number of such ramps can be arbitrary, and their respective inclination angles can also be different. The ramp gradually descends from the furnace front end 11 towards the furnace rear end 12. The preset inclination angle is used to allow the liquid phase material generated at the furnace front end 11 to flow naturally to the furnace rear end 12, and the preset inclination angle is smaller than the angle of repose and angle of accumulation of the solid furnace charge. Further preferably, there is only one ramp, and the part of the ramp furthest from the furnace rear end 12 is the highest, while the part closest to the furnace rear end 12 is the lowest. This allows for... Figure 1As shown, liquid substances generated at any point on the furnace bottom of the front end 11 of the electric furnace can move to the furnace bottom of the rear end 12 of the electric furnace under the influence of gravity and will not remain inside the front end 11. Further details can be found by referring to... Figure 1 The bottom of the electric furnace rear end 12 is preferably a horizontal plane, and the height of the part of the slope closest to the rear end 12 is the same as the bottom of the rear end 12. This ensures that as much liquid material as possible enters the bottom of the rear end 12 and does not remain in the front end 11. Furthermore, the aforementioned preset inclination angle is preferably 3° to 7°. This inclination angle is much smaller than the angle of repose and angle of repose of the solid charge, because the angle of repose of vanadium-titanium pellets is about 23° to 26° and its angle of repose is about 16° to 20°. This prevents a large number of metallized pellets from rolling to the rear end 12 of the electric furnace and affecting the deep reduction process.

[0044] In another specific embodiment of the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the front electrode 111 is used to be embedded in the furnace charge for submerged arc smelting, and the height of the front electrode 111 is 30 cm to 50 cm above the upper edge of the slag-iron taphole. This height difference is reserved to avoid bubbling of the liquid phase. Considering the stability of operation and to ensure that the front electrode 111 is always in the dry zone, its function is only to melt metallized pellets in submerged arc smelting. The rear electrode 121 is only used for open arc smelting, which is above the liquid phase and is mainly used for the reduction of unreduced FeO and vanadium oxides in the slag.

[0045] The front feed port 112 is located around the front electrode 111 and is used for feeding metallized pellets and carbonaceous reducing agent. This positional relationship can ensure uniform feeding in all parts.

[0046] In another specific embodiment of the aforementioned vanadium-titanium magnetite deep reduction electric furnace, referring to... Figure 2 , Figure 2 This is a schematic diagram of the control structure of another specific embodiment of the vanadium-titanium magnetite deep reduction electric furnace. The rear electrode 121 is used for open-arc smelting in liquid phase deep reduction. It can also be connected to the height control device 2. The height control device 2 includes a central control component 21, a lifting component 22 and a slag-iron liquid level recognition component 23, all of which are communicatively connected to it. The central control component 21 controls the lifting component 22 to drive the rear electrode 121 to perform corresponding lifting operations according to the slag-iron liquid level height recognized by the slag-iron liquid level recognition component 23, so that the rear electrode 121 is always located between 15 cm and 25 cm above the slag-iron liquid level and does not exceed the height of the front electrode 111. This height difference can prevent slag from foaming and contacting the electrode, and also ensure low power consumption. It can be seen that no human intervention is required, realizing the automatic adjustment of the height of the rear electrode. This not only saves costs, but also makes the adjustment more precise and can always maintain a certain height difference to ensure the continuous operation of the open-arc smelting process.

[0047] The aforementioned rear feed inlet 122 is preferably located around the aforementioned rear electrode 121 for the addition of carbonaceous reducing agent and / or slag-forming agent during deep reduction smelting. This carbonaceous reducing agent can be coking coal or coke. This arrangement can ensure more uniform feeding. Of course, other methods can be selected according to actual needs, and there are no restrictions here.

[0048] In a preferred embodiment of the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the lower edge of the tap 124 is 5 to 10 centimeters away from the furnace bottom of the rear end 12 of the electric furnace. This can prevent the refractory material at the tap 124 from being eroded and ensure a longer service life. The tap 124 gradually rises from the inner side wall to the outer side wall of the rear end 12 of the electric furnace. It should be noted that since this electric furnace is sealed and maintains sufficient internal pressure, it can be set up in this oblique upward structure.

[0049] In another preferred embodiment of the above-mentioned deep reduction electric furnace for vanadium-titanium magnetite, the centerline of the slag-iron tap 123 is 20 to 50 centimeters higher than the horizontal centerline of the tap 124 on the inner side wall of the rear end 12 of the electric furnace. This slag-iron tap 123 is also a discharge port for controlling the liquid level. This allows for the design of a corresponding effective volume. Of course, it can also be adapted to actual needs, which is not limited here.

[0050] An example of an implementation of the deep reduction smelting method for vanadium-titanium magnetite provided by this invention. Figure 3 As shown, Figure 3 This is a schematic diagram of an embodiment of a deep reduction smelting method for vanadium-titanium magnetite provided by the present invention. Using the deep reduction electric furnace for titanium magnetite as described above, the method specifically includes the following steps:

[0051] S1: Place the front electrode and the rear electrode in the working position, and fill the furnace body with inert gas until the inert gas content is not less than 99%;

[0052] It should be noted that in this step, the electric furnace is sealed, and the inert gas used for filling can be, but is not limited to, argon, to expel the air and prevent the oxygen in it from having an adverse effect on the process.

[0053] S2: When starting the furnace, add a mixed charge of carbonaceous reducing agent and metallized pellets from the front feed port;

[0054] It should be noted that at this point, a mixed charge of carbonaceous reducing agent and metallized pellets (smelting raw material) is added. In subsequent steps, metallized pellets, carbonaceous reducing agent, or a mixture of both can be added separately as needed. The carbonaceous reducing agent can include coke, coke, lump coal, biomass carbon, etc. The proportion of metallized pellets can preferably be 70% to 85% of the mass of the mixed charge.

[0055] S3: Turn on the front electrode. The liquid phase material generated by the melting of the metallized pellets will flow naturally to the rear end of the electric furnace. When the liquid level at the rear end of the electric furnace reaches 20 cm to 30 cm, adjust the height of the rear electrode to 15 cm to 25 cm above the liquid surface, then turn on the rear electrode and add carbonaceous reducing agent at the rear feed inlet.

[0056] It should be noted that the carbonaceous reducing agent here can be coking coal, and an appropriate amount of slagging agent can also be added according to actual smelting needs, such as smelting conditions or raw material conditions.

[0057] S4: During the smelting process, when the pressure inside the electric furnace rises to 0.3MPa to 0.4MPa, the pressure relief valve should be opened in a timely manner to release pressure so that the pressure inside the electric furnace remains within the preset pressure range.

[0058] In this step, as smelting proceeds, substances such as Fe, V, Si, Ti, and Mn in the coke or coke reduction slag generate gases that enter the electric furnace. The gas pressure inside the electric furnace continuously increases. When the pressure inside the electric furnace rises to 0.3 MPa to 0.4 MPa, the pressure inside the furnace is maintained at this level. The pressure relief valve is opened in a timely manner to release pressure. Maintaining a certain pressure inside the furnace can prevent the flooding of liquid slag to a certain extent, and at the same time, it helps to discharge slag and iron and increases the discharge rate of slag and iron.

[0059] S5: As the liquid level in the rear end of the electric furnace rises, the rear electrode is continuously raised until it reaches the same height as the front electrode. The slag and iron outlet is opened until the slag or slag and iron are discharged. At the same time, the rear electrode is controlled to be at a suitable working height and the slag and iron outlet is sealed.

[0060] In this step, the slag tap can be used to control the liquid level when necessary.

[0061] S6: Add carbonaceous reducing agent and metallized pellets to the front end of the electric furnace, and add furnace charge in a timely and appropriate manner according to the material height in the front end of the electric furnace.

[0062] It should be noted that the rear feed port at the back end of the electric furnace is a carbonaceous reducing agent feed port. Flux can also be added according to smelting requirements. This flux can be added or not added according to smelting requirements, including calcium and magnesium fluxes such as limestone, quicklime blocks, and dolomite.

[0063] S7: Open the taphole to discharge the molten iron from the slag taphole, and at the same time control the rear electrode to be at a suitable working height. After the iron discharge is completed, seal the taphole.

[0064] S8: As smelting proceeds, the liquid level at the rear end of the electric furnace and the charge height at the front end of the electric furnace can be continuously observed. Based on the liquid level at the rear end of the electric furnace and the charge height at the front end of the electric furnace, repeat steps S5, S6 and S7 to maintain the pressure inside the electric furnace body at 0.3MPa to 0.4MPa.

[0065] In summary, the above embodiments, by improving the rectangular electric furnace, physically isolate the liquefaction process of submerged arc smelting and the deep reduction process of open arc smelting in the metallization pellets. This optimizes the deep reduction smelting process of vanadium-titanium magnetite metallized pellets in the electric furnace, transforming it from periodic smelting to continuous smelting. This improves production efficiency, reduces the difficulty of deep reduction smelting in the electric furnace, helps improve the heat utilization rate within the electric furnace, reduces power consumption in the deep reduction process, and increases the production efficiency of the deep reduction process. Specifically, in the existing technology, after charging, the electrodes are first submerged arc smelted. After a certain period, the conductivity of the charge increases (the current increases), and the electrodes need to be slowly raised (to prevent excessive current and electrode breakage) until the electrodes are lifted away from the charge. Then, open arc smelting is carried out. After smelting is completed, the slag and iron are discharged, and the above steps are repeated. It can be seen that this smelting process is periodic. The solution in this embodiment can continuously feed and discharge materials, and continuously discharge slag and iron, unlike the existing technology which must go through the process of feeding, smelting and discharging slag and iron, and must wait until the slag and iron are discharged before repeating the above actions in an intermittent periodic smelting process.

[0066] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A deep reduction electric furnace for vanadium-titanium magnetite, characterized in that, include: The electric furnace body has its internal space divided into the front end and the rear end of the furnace. The front electrode and the front feed inlet are located at the upper part of the front end of the electric furnace; The rear electrode and the rear feed inlet are located at the upper part of the rear end of the electric furnace; The slag and iron tapping spout and the iron tapping spout are located on the side of the rear end of the electric furnace, with the slag and iron tapping spout located above the iron tapping spout; The portion of the furnace bottom at the front end of the electric furnace that is farther from the rear end of the electric furnace is higher than the portion near the rear end of the electric furnace. This allows the liquid phase material generated at the front end of the electric furnace to flow naturally to the rear end of the electric furnace, thereby maintaining the front end of the electric furnace in a submerged arc smelting working state, while allowing the rear end of the electric furnace to be in a liquid phase deep reduction open arc smelting working state.

2. The vanadium-titanium magnetite deep reduction electric furnace according to claim 1, characterized in that, The furnace bottom at the front end of the electric furnace includes a slope with a preset angle. The slope gradually descends from the front end of the electric furnace to the rear end of the electric furnace. The preset angle is used to allow the liquid phase material generated at the front end of the electric furnace to flow naturally to the rear end of the electric furnace. The preset angle is smaller than the angle of repose and angle of accumulation of the solid furnace charge.

3. The vanadium-titanium magnetite deep reduction electric furnace according to claim 2, characterized in that, There is only one slope, and the part of the slope furthest from the rear end of the electric furnace is the highest, while the part closest to the rear end of the electric furnace is the lowest.

4. The vanadium-titanium magnetite deep reduction electric furnace according to claim 3, characterized in that, The furnace bottom at the rear end of the electric furnace is a horizontal plane, and the part of the slope closest to the rear end of the electric furnace is at the same height as the furnace bottom at the rear end of the electric furnace.

5. The vanadium-titanium magnetite deep reduction electric furnace according to claim 2, characterized in that, The preset tilt angle is 3° to 7°.

6. The deep reduction electric furnace for vanadium-titanium magnetite according to any one of claims 1-5, characterized in that, The front-end electrode is used to be embedded in the furnace charge for submerged arc smelting, and the height of the front-end electrode is 30 cm to 50 cm above the upper edge of the slag-iron taphole. The front feed port is located around the front electrode and is used for feeding metallized pellets and carbonaceous reducing agent.

7. The deep reduction electric furnace for vanadium-titanium magnetite according to any one of claims 1-5, characterized in that, The rear electrode is used for open-arc smelting of deep liquid phase reduction and is also connected to a height control device. The height control device includes a central control component, a lifting component and a slag-iron liquid level recognition component, all of which are communicatively connected to the central control component. The central control component is used to control the lifting component to drive the rear electrode to perform corresponding lifting operations according to the slag-iron liquid level recognition component, so that the rear electrode is always located between 15 cm and 25 cm above the slag-iron liquid level and does not exceed the height of the front electrode. The rear feed inlet is located around the rear electrode and is used for the addition of carbonaceous reducing agent and / or slagging agent during deep reduction smelting.

8. The deep reduction electric furnace for vanadium-titanium magnetite according to any one of claims 1-5, characterized in that, The lower edge of the tapping spout is 5 to 10 centimeters away from the furnace bottom at the rear end of the electric furnace, and the tapping spout gradually rises along the direction from the inner side wall to the outer side wall at the rear end of the electric furnace.

9. The vanadium-titanium magnetite deep reduction electric furnace according to claim 8, characterized in that, The centerline of the slag-iron taphole is 20 to 50 centimeters higher than the horizontal centerline of the taphole on the inner side wall at the rear end of the electric furnace.

10. A deep reduction smelting method for vanadium-titanium magnetite, characterized in that, The deep reduction electric furnace for vanadium-titanium magnetite as described in any one of claims 1-9 comprises: S1: Place the front electrode and the rear electrode in the working position, and fill the furnace body with inert gas until the content of the inert gas is not less than 99%; S2: When starting the furnace, add a mixed charge of carbonaceous reducing agent and metallized pellets from the front feed port; S3: Turn on the front electrode. The liquid phase material generated by the melting of the metallized pellets flows naturally to the rear end of the electric furnace until the liquid level at the rear end of the electric furnace reaches 20 cm to 30 cm. Then, adjust the height of the rear electrode to 15 cm to 25 cm above the liquid surface and turn on the rear electrode. At the same time, add carbonaceous reducing agent at the rear feed inlet. S4: During the smelting process, when the pressure inside the electric furnace body rises to 0.3MPa to 0.4MPa, the venting valve is opened in a timely manner to release pressure so that the pressure inside the electric furnace body is maintained within the preset pressure range; S5: As the liquid level in the rear end of the electric furnace rises, the rear electrode is continuously raised until it reaches the same height as the front electrode, opening the slag and iron outlet until the slag or slag and iron are discharged. At the same time, the rear electrode is controlled to be at a suitable working height to seal the slag and iron outlet. S6: Add carbonaceous reducing agent and metallized pellets to the front end of the electric furnace, and add furnace charge in a timely and appropriate manner according to the material height in the front end of the electric furnace; S7: Open the tap hole to discharge the molten iron under the slag tap, and at the same time control the rear electrode to be at a suitable working height. After the iron discharge is completed, seal the tap hole. S8: Based on the liquid level at the rear end of the electric furnace and the charge height at the front end of the electric furnace, repeat steps S5, S6 and S7 to maintain the pressure inside the electric furnace body at 0.3MPa to 0.4MPa.

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