Feeding system of submerged arc furnace

Abstract

The utility model relates to the technical field of submerged arc furnace charging, and discloses a submerged arc furnace charging system which comprises a stock bin assembly and a hot material pipe, the stock bin assembly comprises eight hot material bins and a cold material bin, the eight hot material bins are formed by welding Q235 steel plates, and linings of the eight hot material bins and the cold material bin are made of refractory materials; the cold material bin independently feeds materials to the submerged arc furnace through a cold material pipe; the design that the cold material bin and the hot material bin are separated is adopted, interference of cold materials on the internal hot environment of the hot material bin is effectively avoided, the working efficiency and the feeding precision of the hot material bin are improved, and the hot material pipe is used for guiding materials in the hot material bin to be fed into the submerged arc furnace. The bottom of each hot material bin is connected with 3-4 hot material pipes, the number of the hot material pipes is 28, each hot material pipe is of an integrated sectional material pipe structure, each hot material pipe comprises a furnace outer material pipe located on the portion above a furnace cover and a furnace inner material pipe located below the furnace cover and from the portion below the furnace cover to a hearth, and the furnace outer material pipes and the furnace inner material pipes are in transition through flanges and ceramic fiber sealing gaskets. Therefore, thermal stress deformation is avoided, the service life of the material pipe is prolonged, and safety is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of ore smelting furnace feeding, and particularly relates to an ore smelting furnace feeding system. BACKGROUND

[0002] In the operation process of the ore smelting furnace, the feeding system is a crucial component, which is responsible for effectively feeding the furnace charge into the furnace. The traditional ore smelting furnace feeding system usually includes a bunker and a feeding pipeline. These systems may face various challenges during long-term use, such as the destruction of the bunker and pipeline by high-temperature environments, the wear of the pipeline by materials, and issues related to feeding accuracy and efficiency.

[0003] Most of the ore smelting furnace feeding systems on the market currently adopt the following technical solutions: the bunker is usually made of simple steel plates, but such a design may lead to a decrease in structural strength and material damage under the long-term action of high temperatures. The feeding pipeline is mostly of a single-layer structure, which is prone to deformation and wear under the combined action of high temperatures and materials, resulting in a shortened service life. The feeding of cold materials and hot materials is usually mixed, which may interfere with the thermal environment inside the hot bunker and affect the feeding efficiency and accuracy.

[0004] In view of this, an ore smelting furnace feeding system is proposed, which is optimized in terms of high-temperature resistance, structural strength, heat preservation effect, feeding accuracy, material level monitoring accuracy, and maintenance convenience, thereby solving multiple defects in the prior art. INVENTION CONTENTS

[0005] The present invention aims to solve the technical problem that the feeding pipeline in the prior art is mostly of a single-layer structure, which is prone to deformation and wear under the combined action of high temperatures and materials, resulting in a shortened service life.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions:

[0007] An ore smelting furnace feeding system includes a bunker assembly and a hot material pipe. The bunker assembly includes eight hot bunkers and one cold bunker, which are formed by welding Q235 steel plates and lined with refractory materials. The thickness of the lining of the hot bunkers is designed such that the outer surface temperature of the hot bunkers is lower than the maximum use temperature of the load cell. The cold bunker feeds cold materials to the ore smelting furnace through a cold material pipe; the hot material pipe is used to guide the materials in the hot bunkers to the ore smelting furnace;

[0008] The bottom of each hot bunker is connected to 3-4 hot material pipes, and there are a total of 28 hot material pipes. The hot material pipes adopt an integrated segmented pipe structure. The hot material pipes include an external pipe above the furnace cover and an internal pipe below the furnace cover to the hearth. The external pipe and the internal pipe are connected through flanges and ceramic fiber sealing pads to avoid thermal stress deformation.

[0009] The outer furnace material pipe comprises a transition pipe, a transition section, an insulating material pipe, an upper section material pipe, a middle section material pipe and an inner material pipe; a needle valve is connected with the discharge port flange of the hot material bin, the bottom flange of the needle valve is connected with the transition pipe, and a rotary cutting type high-temperature wear-resistant discharge valve is connected with the flange between the transition pipe and the transition section.

[0010] The inner furnace material pipe comprises a lower section material pipe A, a lower section material pipe B and a lower material nozzle.

[0011] As preferred, each hot material bin is provided with four weighing sensors, which monitor the material level in real time and feed back to the PLC system, the weighing sensors are installed on independent support frames and are isolated from the hot material bin, so that the precision is not affected by the refractory masonry;

[0012] The PLC system controls the rotary cutting type high-temperature wear-resistant discharge valve through a PID algorithm, so that the discharge amount deviation is less than or equal to ± 2%.

[0013] As preferred, the outer furnace material pipe has an inner diameter DN400, a wall thickness of 12 mm and is made of Q235 material; the outer furnace material pipe is externally coated with a 50 mm thick aluminosilicate fiber insulation layer and is fixed by using a stainless steel band.

[0014] The inner furnace material pipe has an inner diameter DN500, a wall thickness of 15 mm and is made of ZG1Cr25Ni20 material, the inner furnace material pipe extends to a position two meters away from the furnace cover and the surface of the inner furnace material pipe is coated with a silicon carbide wear-resistant coating, and the outer wall of the inner furnace material pipe is provided with a spiral water cooling interlayer for circulating cooling of softened water to delay high-temperature burning.

[0015] As preferred, the valve core of the rotary cutting type high-temperature wear-resistant discharge valve is made of 0Cr25Ni20 casting, and a tungsten carbide wear-resistant lining plate with a thickness greater than or equal to 8 mm is embedded in the valve core, and the valve body of the rotary cutting type high-temperature wear-resistant discharge valve is externally coated with a double-layer stainless steel water cooling jacket, and the cooling water inlet and outlet are arranged on the two sides of the valve body; the contact surface between the valve seat and the valve core is embedded with a silicon carbide sealing ring, and the temperature resistance reaches 1600 DEG C.

[0016] As preferred, the transition section is nested in the insulating material pipe to form a double-layer structure, and the insulating material pipe, the upper section material pipe, the middle section material pipe and the inner material pipe are sequentially flange-connected from top to bottom.

[0017] As preferred, the lower section material pipe A, the lower section material pipe B and the lower material nozzle are sequentially flange-connected from top to bottom, and the inner material pipe is nested in the lower section material pipe A to form a double-layer structure.

[0018] As preferred, the insulating material pipe adopts a double-layer sleeve structure, the inner layer is a high-temperature resistant ceramic fiber pipe, and the outer layer is coated with an aluminosilicate insulation layer.

[0019] Compared with the prior art, the technical effects and advantages of the utility model are:

[0020] The design of separate cold bin and hot bin effectively avoids the interference of cold material on the internal thermal environment of the hot bin, improving the working efficiency and feeding accuracy of the hot bin. The hot material pipe at the bottom of each hot bin adopts an integrated segmented structure, including an external material pipe and an internal material pipe, connected by flanges and ceramic fiber sealing pads to adapt to thermal stress deformation and ensure system stability. In addition, the system is equipped with a precise PLC control system, which controls the rotary cutting high-temperature wear-resistant discharge valve through a PID algorithm to achieve precise control of the discharge amount.

[0021] The design of separate cold bin and hot bin effectively avoids the interference of cold material on the internal thermal environment of the hot bin, improving the working efficiency and feeding accuracy of the hot bin. At the same time, multiple hot material pipes are connected at the bottom of the hot bin, adopting a segmented structure to help cope with thermal stress deformation, improve the service life and safety of the material pipe. These designs not only enhance the stability of the system, but also improve the thermal efficiency and reduce energy waste.

[0022] The design of the hot material pipe of the submerged arc furnace feeding system takes into account the challenges of high temperature and wear. The ZG1Cr25Ni20 material with an inner diameter of DN500 and a wall thickness of 15mm has good high-temperature resistance, and the surface coated with silicon carbide wear-resistant coating further improves the wear resistance of the material pipe. In addition, the design of the spiral water-cooled sandwich can circulate cooling water to reduce the temperature of the material pipe and delay high-temperature burning, thereby significantly improving the service life of the material pipe. These measures ensure the long-term stable operation of the material pipe in high-temperature and wear environments. The precise control system and wear-resistant discharge valve design further enhance the performance of the system. The valve core of the rotary cutting high-temperature wear-resistant discharge valve is made of 0Cr25Ni20 casting and embedded with tungsten carbide wear-resistant lining plate, improving the wear resistance and high-temperature resistance. The valve body is wrapped with a double-layer stainless steel water-cooled jacket, effectively reducing the temperature of the valve body and increasing the service life of the valve. The PLC system controls the discharge valve through a PID algorithm to achieve precise control of the discharge amount, with a deviation of not more than ±2%, thereby ensuring the accuracy and stability of the feeding amount. BRIEF DESCRIPTION OF DRAWINGS

[0023] Fig. 1 is a top view of the present utility model;

[0024] Fig. 2 is a structural schematic view of the hot bin and hot material pipe of the present utility model.

[0025] In the figure: 1, hot bin; 2, hot material pipe; 3, needle valve; 4, transition pipe; 5, rotary cutting high-temperature wear-resistant discharge valve; 6, transition section; 7, insulated material pipe; 8, upper section material pipe; 9, middle section material pipe; 10, internal material pipe; 11, lower section material pipe A; 12, lower section material pipe B; 13, discharge nozzle; 14, weighing sensor; 15, support frame. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0027] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model. Figs. 1-2 The utility model is further described in detail as follows,

[0028] The utility model discloses a kind of ore-heating furnace feeding systems, including bunker assembly and hot material pipe 2, bunker assembly includes eight hot material bunker 1 and one cold material bunker using Q235 steel plate welding forming and lining with refractory material;Using Q235 steel plate welding forming and lining with refractory material, the high temperature resistance and structural strength of bunker are enhanced.

[0029] Cold material bunker is separately fed to ore-heating furnace by cold material pipe;Hot material pipe 2 is used to guide the material in hot material bunker 1 to ore-heating furnace;The separation of cold material bunker and hot material bunker 1, cold material bunker is separately fed to ore-heating furnace, avoid the interference of cold material to the internal thermal environment of hot material bunker 1, improve the working efficiency and feeding precision of hot material bunker 1.

[0030] Each hot material bunker 1 is equipped with four load cells 14, real-time monitoring material level and feedback to PLC system, load cell 14 is installed on independent support frame 15 and is isolated with hot material bunker 1, avoid the influence of refractory material masonry on precision;The thickness design of lining with refractory material in hot material bunker 1 makes the outer surface temperature of hot material bunker 1 lower than the highest use temperature of load cell 14.Effectively protect load cell 14 from high temperature, guarantee the accuracy of material level monitoring.

[0031] The bottom of each hot material bunker 1 is connected with 3-4 hot material pipes 2, a total of 28 hot material pipes 2, hot material pipe 2 adopts integrated sectional type pipe structure, and hot material pipe 2 includes an outer furnace pipe above the furnace cover and an inner furnace pipe 10 below the furnace cover to the hearth portion, and the outer furnace pipe and the inner furnace pipe 10 are transitioned by a flange and a ceramic fiber sealing gasket to avoid thermal stress deformation.

[0032] The sectional type pipe structure of hot material pipe 2 helps to cope with thermal stress deformation, improves the service life and safety of the pipe.

[0033] The outer furnace pipe has an inner diameter DN400 and a wall thickness of 12mm and is made of Q235 material;The outer furnace pipe is externally coated with a 50mm thick alumina-silica fiber insulation layer and is fixed by a stainless steel band.

[0034] This design provides sufficient mechanical strength and pressure resistance to withstand the pressure and wear generated during material conveying. The application of a 50mm thick silica alumina fiber insulation layer can effectively reduce heat loss, improve thermal efficiency, and reduce the impact of thermal energy on the surrounding environment. The stainless steel banding fixation increases the stability of the insulation layer, prevents the insulation material from falling off, and ensures long-term stable insulation effect.

[0035] The inner tube 10 has a diameter DN500 and a wall thickness of 15mm, made of ZG1Cr25Ni20 material, and extends to two meters away from the furnace cover. The surface of the inner tube 10 is coated with a silicon carbide wear-resistant coating, and the outer wall of the inner tube 10 is provided with a spiral water-cooled layer for circulating soft water cooling to delay high-temperature burning.

[0036] The ZG1Cr25Ni20 material with an inner diameter of DN500 and a wall thickness of 15mm has very high high-temperature resistance, suitable for high-temperature environment in the furnace. The surface coated with silicon carbide wear-resistant coating improves the wear resistance of the tube, reduces the wear of the tube by the material, and prolongs the service life of the tube. The spiral water-cooled layer can circulate cooling water to reduce the temperature of the tube, delay high-temperature burning, and improve the service life of the tube.

[0037] The outer tube includes a transition pipe 4, a transition section 6, an insulated tube 7, an upper tube 8, a middle tube 9, and an inner tube 10. The needle valve 3 is connected to the flange of the discharge port of the hot bin 1, the transition pipe 4 is connected to the flange between the transition section 6 and the transition pipe 4, and the rotary cutting high-temperature wear-resistant discharge valve 5 is connected to the flange between the transition section 6 and the transition pipe 4. The transition section 6 is nested in the insulated tube 7 to form a double-layer structure, improving the stability of the structure and ensuring the insulation performance of the tube in high-temperature environment. The insulated tube 7, the upper tube 8, the middle tube 9, and the inner tube 10 are connected in sequence from top to bottom. The insulated tube 7 adopts a double-layer sleeve structure, with a high-temperature resistant ceramic fiber tube in the inner layer and a silica alumina insulation layer in the outer layer.

[0038] The valve core of the rotary cutting high-temperature wear-resistant discharge valve 5 is made of 0Cr25Ni20 casting, with a tungsten carbide wear-resistant lining plate with a thickness of ≥8mm embedded inside, improving the wear resistance and high-temperature resistance. The valve body of the rotary cutting high-temperature wear-resistant discharge valve 5 is wrapped with a double-layer stainless steel water-cooled sleeve, with cooling water inlets and outlets on both sides of the valve body. This effectively reduces the temperature of the valve body and increases the service life of the valve. The valve seat and the valve core contact surface are embedded with a silicon carbide sealing ring, which improves the sealing performance and can withstand temperatures up to 1600℃, ensuring the sealing effect at high temperatures. The PLC system controls the rotary cutting high-temperature wear-resistant discharge valve 5 through the PID algorithm, achieving a discharge amount deviation of ≤±2%, ensuring the accuracy and stability of the discharge amount.

[0039] The inner material pipe 10 includes a lower section pipe A11, a lower section pipe B12, and a lower nozzle 13. The lower section pipe A11, the lower section pipe B12, and the lower nozzle 13 are connected in sequence from top to bottom by flanges, and the inner material pipe 10 is nested in the lower section pipe A11 to form a double-layer structure. The flange connection of the lower section pipe A11, the lower section pipe B12, and the lower nozzle 13 makes the structure more stable and facilitates maintenance and replacement of parts. The nesting of the inner material pipe 10 in the lower section pipe A11 forms a double-layer structure, which improves the support and stability of the inner material pipe 10 and increases the wear resistance, ensuring the long-term stable operation of the material pipe in high-temperature and wear environments.

[0040] The ore smelting furnace feeding system mainly includes the design of the hopper assembly, the structure of the hot material pipe 2, and the precise control system. The hopper assembly is welded from high-temperature-resistant Q235 steel plates and lined with refractory materials, enhancing the hopper's high-temperature resistance and structural strength. The hot material pipe 2 adopts a segmented structure, including an outer furnace material pipe and an inner furnace material pipe 10, connected by flanges and ceramic fiber sealing pads to accommodate thermal stress deformation and ensure system stability. In addition, the system is equipped with a precise PLC control system that controls the rotary cutting high-temperature wear-resistant discharge valve 5 through a PID algorithm, achieving precise control of the discharge amount.

[0041] The ore smelting furnace feeding system effectively avoids interference from cold materials on the internal thermal environment of the hot hopper 1 by adopting a separate cold hopper and hot hopper 1 design, improving the efficiency and accuracy of the hot hopper 1. At the same time, the hot hopper 1 is connected to multiple hot material pipes 2 at the bottom, adopting a segmented structure that helps to cope with thermal stress deformation, improving the service life and safety of the material pipe. These designs not only enhance the stability of the system but also improve thermal efficiency and reduce energy waste.

[0042] The system's hot material pipe 2 design takes into account the challenges of high temperature and wear. The ZG1Cr25Ni20 material with an inner diameter of DN500 and a wall thickness of 15mm has good high-temperature resistance, and the surface coated with a silicon carbide wear-resistant coating further improves the wear resistance of the material pipe. In addition, the design of the spiral water-cooled sandwich can circulate cooling water to reduce the temperature of the material pipe and delay high-temperature burning, thereby significantly improving the service life of the material pipe. These measures ensure the long-term stable operation of the material pipe in high-temperature and wear environments.

[0043] The precise control system and wear-resistant discharge valve design further enhance the performance of the system. The valve core of the rotary cutting high-temperature wear-resistant discharge valve 5 is made of 0Cr25Ni20 casting and embedded with a tungsten carbide wear-resistant lining plate, improving wear resistance and high-temperature resistance. The valve body is wrapped with a double-layer stainless steel water-cooled jacket, effectively reducing the temperature of the valve body and increasing the service life of the valve. The PLC system controls the discharge valve through a PID algorithm, achieving precise control of the discharge amount with a deviation of not more than ±2%, thereby ensuring the accuracy and stability of the feeding amount.

[0044] It should be pointed out finally that: the above only for the preferred embodiments of the utility model have, and do not for limiting the utility model, although the utility model has been described in detail with reference to the foregoing embodiments, for the person skilled in the art, it still can modify the technical scheme recorded in the foregoing each embodiment, or equivalent replacement to part of technical features, any modification, equivalent replacement, improvement etc. that is made within the spirit and principles of the utility model, should be included in the protection scope of the utility model.

Claims

1. An ore smelting furnace charging system, characterized in that, The application relates to a hot material feeding device for a submerged arc furnace. The hot material feeding device comprises a bin assembly which comprises eight hot material bins (1) and one cold material bin which are formed by welding Q235 steel plates and are lined with refractory materials; the cold material bin is separately fed to the submerged arc furnace through a cold material pipe; The hot material pipe (2) is used for guiding the material in the hot material bin (1) to the submerged arc furnace; the bottom of each hot material bin (1) is connected with 3-4 hot material pipes (2), and there are totally 28 hot material pipes (2); the hot material pipe (2) adopts an integrated sectional pipe structure; the hot material pipe (2) comprises an outer pipe above the furnace cover and an inner pipe (10) below the furnace cover; the outer pipe and the inner pipe (10) are connected through flanges and ceramic fiber sealing pads. The outer pipe comprises a transition pipe (4), a transition section (6), an insulating pipe (7), an upper section pipe (8), a middle section pipe (9) and the inner pipe (10); the needle valve (3) is connected with the flange at the discharge port of the hot material bin (1); the transition pipe (4) is connected with the flange between the transition section (6) and the high-temperature wear-resistant rotary cutting discharge valve (5). The inner pipe (10) comprises a lower section pipe A (11), a lower section pipe B (12) and a discharge nozzle (13).

2. A charging system for an ore smelting furnace as claimed in claim 1, characterized in that Each hot material bin (1) is provided with four weighing sensors (14) which are used for monitoring the material level in real time and feeding back to a PLC system; the weighing sensors (14) are installed on independent support frames (15) and are isolated from the hot material bin (1).

3. A charging system for an ore smelting furnace as claimed in claim 1, characterized in that The outer pipe has an inner diameter of DN400, a wall thickness of 12mm and is made of Q235 material; the outer pipe is externally coated with a 50mm-thick aluminosilicate fiber heat preservation layer and is fixed through stainless steel bands. The inner pipe (10) has an inner diameter of DN500, a wall thickness of 15mm and is made of ZG1Cr25Ni20 material; the inner pipe (10) extends to a position two meters away from the furnace cover and is coated with a silicon carbide wear-resistant coating on the surface; a spiral water cooling layer is arranged on the outer wall of the inner pipe (10) and is used for circulating cooling of softened water to delay high-temperature burning.

4. A charging system for an ore smelting furnace as claimed in claim 1, characterized in that: The valve core of the high-temperature wear-resistant rotary cutting discharge valve (5) is made of 0Cr25Ni20 casting and is embedded with a tungsten carbide wear-resistant lining plate with a thickness greater than or equal to 8mm; the valve body of the high-temperature wear-resistant rotary cutting discharge valve (5) is externally coated with a double-layer stainless steel water cooling jacket; the cooling water inlet and outlet are arranged on the two sides of the valve body; the contact surface between the valve seat and the valve core is embedded with a silicon carbide sealing ring.

5. A charging system for an ore smelting furnace as claimed in claim 1, characterized in that: The transition section (6) is nested in the insulating pipe (7) to form a double-layer structure; the insulating pipe (7), the upper section pipe (8), the middle section pipe (9) and the inner pipe (10) are sequentially connected through flanges from top to bottom.

6. A charging system for an ore smelting furnace as claimed in claim 1, characterized in that: The lower section pipe A (11), the lower section pipe B (12) and the discharge nozzle (13) are sequentially connected through flanges from top to bottom; the inner pipe (10) is nested in the lower section pipe A (11) to form a double-layer structure.

7. A charging system for an ore smelting furnace as claimed in claim 5, characterized in that The insulating pipe (7) adopts a double-layer sleeve structure; the inner layer is a high-temperature resistant ceramic fiber pipe; the outer layer is coated with an aluminosilicate heat preservation layer.

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