Smelting electric arc furnace and system

Abstract

The invention provides a smelting electric arc furnace and system, and relates to the technical field of smelting equipment, the smelting electric arc furnace comprises a furnace body, an electrode assembly, a furnace door and a pressing mechanism, and the furnace body is provided with a feeding port, a smoke outlet, a bottom blowing port, a slag outlet and a steel outlet; the electrode assembly comprises at least one first electrode; the furnace door is arranged on the furnace body in an openable manner; the pressing mechanism comprises a pushing head and a connecting piece connected with the pushing head, when the furnace door is located at the opening position, the connecting piece can drive the pushing head to stretch into the furnace body through the furnace door, and the pushing head can be used for pressing raw materials floating on a molten pool in the furnace body into the molten pool. Compared with the prior art, the direct reduction iron (DRI) raw material floating on the molten pool can be pressed into molten steel, the number of the direct reduction iron (DRI) raw material floating on the molten pool is reduced, the metal recovery rate of the direct reduction iron (DRI) is further increased, the air sealing structure can play an air sealing role on the furnace body in the smelting process, and therefore production of low-nitrogen steel is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of smelting equipment, and in particular to a smelting electric arc furnace and a system. Background Art

[0002] The electric arc furnace is an important smelting equipment. The electric arc furnace can melt the steelmaking raw materials through the electric arc generated between the electrode and the steelmaking raw materials, thereby realizing the flat molten pool smelting of the arc-heated molten steel. Direct reduced iron (DRI) is a low-carbon porous substance formed by low-temperature reduction of refined iron powder or iron oxide in the furnace. It has a stable chemical composition and low impurity content. It is mainly used as a raw material for electric furnace steelmaking. Since direct reduced iron (DRI) is a porous substance, the density of direct reduced iron (DRI) is less than the density of molten steel, which makes direct reduced iron (DRI) easy to float in the molten pool. In addition, when the proportion of direct reduced iron (DRI) added is high, direct reduced iron (DRI) is easy to be discharged from the molten pool with the slag liquid, thereby reducing the metal recovery rate of direct reduced iron (DRI). In addition, when the electric arc furnace is used, the electric arc generated by the electric arc furnace will ionize the nitrogen in the air, so that the nitrogen ions enter the molten steel, resulting in a high nitrogen content in the steel, thereby reducing the quality of the steel, making it difficult for the steel to meet the needs of automobile manufacturing. Summary of the invention

[0003] In order to overcome the above-mentioned defects of the prior art, the technical problem to be solved by the embodiments of the present invention is to provide a smelting arc furnace and a system for solving at least one of the above-mentioned technical problems.

[0004] The above-mentioned object of the present invention can be achieved by adopting the following technical scheme. The present invention provides a smelting arc furnace, comprising:

[0005] A furnace body, wherein the furnace body is provided with a feed inlet, a smoke outlet, a bottom blowing inlet, a slag outlet and a steel outlet;

[0006] An electrode assembly, the electrode assembly comprising at least one first electrode inserted and disposed in the furnace body;

[0007] A furnace door, the furnace door is openably arranged on the furnace body, and the furnace door has an open position and a closed position;

[0008] The pressing mechanism includes a push head and a connecting piece connected to the push head. When the furnace door is in the open position, the connecting piece can drive the push head to extend into the furnace body through the furnace door. The push head can be used to press the raw materials floating on the molten pool in the furnace body into the molten pool.

[0009] In a preferred embodiment of the present invention, a protective layer is provided on the pusher head.

[0010] In a preferred embodiment of the present invention, the protective layer includes a magnesia layer arranged on the pusher head, and before the pusher head enters the furnace body, the pusher head is calcined at a calcination temperature of not less than 1200°C.

[0011] In a preferred embodiment of the present invention, the connecting member includes a molten salt cooling pipe, and the molten salt cooling pipe is connected to the pusher head.

[0012] In a preferred embodiment of the present invention, the diameter of the pusher head is 50ccm-70cm, and the thickness of the pusher head is not less than 8mm.

[0013] In a preferred embodiment of the present invention, the smelting electric arc furnace further comprises a camera device disposed in the furnace body, and the camera device is used to photograph the state of the molten pool in the furnace body.

[0014] In a preferred embodiment of the present invention, the smelting arc furnace further comprises a cooling structure, and the cooling structure is heat exchangeably connected to the camera device.

[0015] In a preferred embodiment of the present invention, the cooling structure includes a cooling cabin, the camera device is arranged in the cooling cabin, a cooling channel is provided in the cooling cabin, and the cooling channel can be used to transport carbon dioxide to cool the camera device.

[0016] In a preferred embodiment of the present invention, the smelting electric arc furnace further comprises a slag port disposed on the furnace body, and the slag port is used to connect to a high-level silo.

[0017] In a preferred embodiment of the present invention, the smelting electric arc furnace further includes a first gas sealing structure arranged between the furnace door and the furnace body, and a second gas sealing structure arranged between the first electrode and the furnace body.

[0018] In a preferred embodiment of the present invention, the first gas sealing structure includes a first gas sealing tube arranged around the periphery of the furnace door, the first gas sealing tube is provided with a plurality of first injection holes, and the first gas sealing tube is used to transport carbon dioxide; the second gas sealing structure includes a second gas sealing tube arranged around the periphery of the first electrode, the second gas sealing tube is provided with a plurality of second injection holes, and the second gas sealing tube is used to transport argon.

[0019] In a preferred embodiment of the present invention, the smelting electric arc furnace further comprises a spray gun mechanism, wherein the spray gun mechanism comprises at least one spray gun connected to the furnace body, and the spray gun is used to spray carbon and / or oxygen into the furnace body.

[0020] In a preferred embodiment of the present invention, the first electrode comprises a graphite electrode, and the graphite electrode is inserted and disposed in the furnace body.

[0021] In a preferred embodiment of the present invention, the electrode assembly further comprises a bottom electrode, and the bottom electrode is arranged on the furnace body and placed below the first electrode.

[0022] The invention also discloses a smelting system, comprising the above-mentioned smelting electric arc furnace.

[0023] In a preferred embodiment of the present invention, the smelting system further comprises a feeding mechanism, and the feeding mechanism comprises a feeding hopper and a feeding chute connecting the feeding hopper and a feeding port.

[0024] In a preferred embodiment of the present invention, the smelting system also includes a hot charging and hot conveying device, which connects the charging hopper and the DRI outlet of the vertical furnace, and is used to convey the DRI raw material output from the DRI outlet of the vertical furnace to the charging hopper.

[0025] In a preferred embodiment of the present invention, the hot charging and hot delivery device includes a conveying trough and a driving device arranged on the conveying trough, the DRI outlet of the vertical furnace is connected to one end of the conveying trough through a connecting hose, and the other end of the conveying trough is connected to the charging hopper, and the driving device can be used to vibrate the conveying trough to transport the DRI raw material. A third gas sealing structure is provided between the conveying trough and the charging hopper, and the third gas sealing structure includes a third gas sealing pipe and a plurality of third gas injection holes arranged on the third gas sealing pipe, and the third gas sealing pipe is used to transport argon gas.

[0026] In a preferred embodiment of the present invention, the smelting system further comprises a holding mechanism, which comprises a holding arm and a rotating device for driving the holding arm for rotational adjustment, and the holding arm is connected to the feeding hopper and / or the feeding chute.

[0027] In a preferred embodiment of the present invention, the smelting system further comprises a slag hopper and a slag pipe connecting the slag hopper and a slag port, and an outlet of the slag hopper is provided with an adjustable sliding baffle.

[0028] In a preferred embodiment of the present invention, the smelting system also includes a high-level silo, the outlet of the high-level silo is connected to the slag hopper, and a fourth gas sealing structure is provided between the high-level silo and the slag hopper, the fourth gas sealing structure includes a fourth gas sealing pipe and a plurality of fourth jet holes arranged on the fourth gas sealing pipe, and the fourth gas sealing pipe is used to transport argon gas.

[0029] In a preferred embodiment of the present invention, the smelting system further comprises a slag overflow pipe for connecting to the slag overflow port, and the slag overflow pipe is arranged at an inclination through a bracket.

[0030] In a preferred embodiment of the present invention, a slag pipe electromagnetic brake is provided on the slag overflow pipe.

[0031] In a preferred embodiment of the present invention, the smelting system further includes a smoke exhaust pipe for connecting to a smoke outlet, and a fan arranged on the smoke exhaust pipe.

[0032] In a preferred embodiment of the present invention, a smoke exhaust pipe electromagnetic brake is provided on the smoke exhaust pipe.

[0033] The technical solution of the present invention has the following significant beneficial effects:

[0034] When the smelting electric arc furnace of the present invention is used, the feed port, the smoke outlet, the bottom blowing port, the slag outlet and the steel outlet are arranged on the furnace body, so that various materials can be more conveniently input or output, thereby improving the smelting efficiency of the smelting electric arc furnace. In addition, by plugging the first electrode arranged in the furnace body, the first electrode can generate an arc with the steelmaking raw material to melt the steelmaking raw material to form a flat molten pool smelting, which has better heating efficiency.

[0035] When direct reduced iron (DRI) is used as a raw material for steelmaking, since the density of direct reduced iron (DRI) is lower than that of molten steel, direct reduced iron (DRI) tends to float in the molten pool, and direct reduced iron (DRI) tends to be discharged from the furnace along with the slag, thereby reducing the metal recovery rate of direct reduced iron (DRI).

[0036] In order to solve the above problems, an openable furnace door and a pressing mechanism are also provided on the furnace body. When direct reduced iron (DRI) is observed floating on the molten pool, the furnace door is opened, and then the pusher head is driven by the connecting piece to extend into the furnace body through the furnace door, and the pusher head is used to press the raw materials floating on the molten pool, and the direct reduced iron (DRI) raw materials floating on the molten pool are pressed into the molten steel, thereby reducing the amount of direct reduced iron (DRI) raw materials floating on the molten pool, and then improving the metal recovery rate of direct reduced iron (DRI).

[0037] Furthermore, by providing a first gas sealing structure, a second gas sealing structure, a third gas sealing structure and a fourth gas sealing structure, the gas sealing structure can be used to seal the furnace body during the smelting process, thereby preventing external air from entering the furnace body, and avoiding the arc generated by the first electrode ionizing nitrogen in the air, and then nitrogen ions entering the molten steel, causing the problem of a high nitrogen content in the steel. The smelting arc furnace described in the present invention can also achieve the production of low-nitrogen steel, thereby better realizing the manufacturing of high-end "green steel". BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] The accompanying drawings described herein are only for explanation purposes and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the various components in the figures are only schematic, used to help understand the present invention, and are not specifically limited to the shapes and proportional dimensions of the various components of the present invention. Those skilled in the art can select various possible shapes and proportional dimensions to implement the present invention according to the teachings of the present invention.

[0040] Figure 1 It is a schematic structural diagram of an embodiment of the smelting electric arc furnace described in the present invention.

[0041] Reference numerals of the above drawings:

[0042] 100, furnace body; 110, feed port; 120, flue gas outlet; 130, bottom blowing port; 140, slag outlet; 150, steel outlet; 160, slag outlet; 170, camera device; 180, cooling cabin; 190, spray gun;

[0043] 200, electrode assembly; 210, first electrode; 220, bottom electrode;

[0044] 300, furnace door;

[0045] 400, pressing mechanism; 410, pushing head; 420, connecting piece;

[0046] 510, first air-sealing structure; 520, second air-sealing structure; 530, third air-sealing structure; 540, fourth air-sealing structure;

[0047] 610, charging hopper; 620, charging chute; 630, hot charging and hot delivery device; 631, conveying trough; 632, driving device; 640, DRI outlet of vertical furnace; 650, holding arm; 660, rotating device;

[0048] 710, slag hopper; 720, slag pipe; 730, sliding baffle; 740, high-level silo;

[0049] 810, slag overflow pipe; 820, slag pipe electromagnetic brake;

[0050] 910. Smoke exhaust pipe; 920. Fan; 930. Smoke pipe electromagnetic brake. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Implementation Method 1

[0053] Please refer to Figure 1 As shown, an embodiment of the present invention provides a smelting electric arc furnace, which includes a furnace body 100, an electrode assembly 200, a furnace door 300 and a pressing mechanism 400. The furnace body 100 is provided with a feed port 110, a flue gas outlet 120, a bottom blowing port 130, a slag outlet 140 and a steel outlet 150; the electrode assembly 200 includes at least one first electrode 210 inserted into the furnace body 100; the furnace door 300 is openably arranged on the furnace body 100, and the furnace door 300 has an open position and a closed position; the pressing mechanism 400 includes a push head 410 and a connecting member 420 connected to the push head 410. When the furnace door 300 is in the open position, the connecting member 420 can drive the push head 410 to extend into the furnace body 100 through the furnace door 300, and the push head 410 can be used to press the raw materials floating on the molten pool in the furnace body 100 into the molten pool.

[0054] On the whole, when the smelting arc furnace is used, the feed port 110, the flue gas outlet 120, the bottom blowing port 130, the slag outlet 140 and the steel outlet 150 are arranged on the furnace body 100, so that various materials can be more conveniently input or output, thereby improving the smelting efficiency of the smelting arc furnace. In addition, by plugging the first electrode 210 arranged in the furnace body 100, the first electrode 210 can generate an arc with the steelmaking raw material to melt the steelmaking raw material to form a flat molten pool smelting, which has better heating efficiency.

[0055] When direct reduced iron (DRI) is used as a raw material for steelmaking, since the density of direct reduced iron (DRI) is lower than that of molten steel, the direct reduced iron (DRI) is easy to float in the molten pool, and the direct reduced iron (DRI) is easy to be discharged from the furnace body 100 along with the slag liquid, thereby reducing the metal recovery rate of the direct reduced iron (DRI).

[0056] In order to solve the above problems, an openable furnace door 300 and a pressing mechanism 400 are further provided on the furnace body 100. When direct reduced iron (DRI) is observed to float on the molten pool, the furnace door 300 is opened, and then the connecting piece 420 is used to drive the pusher head 410 to extend into the furnace body 100 through the furnace door 300, and the pusher head 410 can be used to press the raw materials floating on the molten pool, and the direct reduced iron (DRI) raw materials floating on the molten pool are pressed into the molten steel, thereby reducing the amount of direct reduced iron (DRI) raw materials floating on the molten pool, thereby improving the metal recovery rate of direct reduced iron (DRI), and having a better smelting effect.

[0057] In a feasible embodiment of the present invention, the feed inlet 110 and the smoke outlet 120 are arranged at the top or upper part of the furnace body 100, the bottom blowing port 130, the slag outlet 140 and the steel outlet 150 are arranged in the middle or lower part of the furnace body 100, and the furnace door 300 is arranged on the side wall of the furnace body 100 in a liftable manner.

[0058] Of course, in other embodiments, designers can adjust the specific locations of the feed port 110, the smoke outlet 120, the bottom blowing port 130, the slag outlet 140 and the steel outlet 150 according to usage requirements, and no specific restrictions are made here.

[0059] In the embodiment of the present invention, the designer can adjust the number of the first electrodes 210 according to the use requirements, and no specific limitation is made here. In one feasible embodiment, one first electrode 210 can be provided. In another feasible embodiment, a plurality of first electrodes 210 can be provided, and the arc heating efficiency is improved by synergistically using the plurality of first electrodes 210.

[0060] In the embodiment of the present invention, a protective layer is provided on the pusher head 410. By providing the protective layer on the pusher head 410, the high temperature of the molten pool in the furnace body 100 can be prevented from directly acting on the pusher head 410, thereby helping to increase the service life of the pusher head 410. Designers can adjust the specific material of the protective layer according to the use requirements, such as metal materials, non-metallic materials, etc., and no specific restrictions are made here.

[0061] Preferably, the protective layer includes a magnesia layer disposed on the pusher head 410 , and before the pusher head 410 enters the furnace body 100 , the pusher head 410 is calcined, and the calcination temperature is not less than 1200° C.

[0062] By calcining the pusher head 410 and the magnesia layer, the magnesia layer on the outer layer of the pusher head 410 is ensured to be dense, which plays a better protective role and significantly improves the service life of the pusher head 410.

[0063] In an embodiment of the present invention, the connector 420 includes a molten salt cooling pipe, which is connected to the pusher head 410. The molten salt cooling pipe has better heat resistance and can be used in a high temperature environment in the furnace body 100.

[0064] By connecting the molten salt cooling pipe to the pusher head 410, the molten salt cooling pipe can drive the pusher head 410 to move, and then the pusher head 410 can be used to press the direct reduced iron (DRI) raw material floating on the molten pool into the molten steel.

[0065] Of course, in other feasible embodiments, designers can adjust the specific structure of the connector 420 according to usage requirements, and no specific limitation is made here.

[0066] Among them, the designer can drive the molten salt cooling tube and the pusher head 410 through an external device to realize the pressing action, thereby improving the movement efficiency of the molten salt cooling tube and the pusher head 410. The designer can adjust the specific structure of the external device according to the use needs. For example, the external device can be set to a hydraulic device, a pneumatic device or a mechanical arm, etc., which is not specifically limited here.

[0067] Designers can adjust the shape and size of the pusher head 410 according to usage requirements. For example, the pusher head 410 can be set to a circular, rectangular or other shape, which is not specifically limited here.

[0068] Preferably, the pusher head 410 is substantially circular in shape. More preferably, the diameter of the pusher head 410 is 50 cm to 70 cm, and the thickness of the pusher head 410 is not less than 8 mm.

[0069] In an embodiment of the present invention, the smelting arc furnace further includes a camera device 170 disposed in the furnace body 100 , and the camera device 170 is used to photograph the state of the molten pool in the furnace body 100 .

[0070] By arranging the camera device 170 in the furnace body 100, it is convenient to monitor the state of the molten pool in the furnace body 100 in real time, so that the operator can immediately know the amount of direct reduced iron (DRI) floating on the molten pool. When the floating direct reduced iron (DRI) exceeds the preset value, the operator can control the pusher head 410 to press the direct reduced iron (DRI) into the molten steel.

[0071] The designer can adjust the specific structure of the camera device 170 according to the use requirements, and no specific limitation is made here. Preferably, the camera device 170 includes a camera disposed in the furnace body 100 .

[0072] Since the furnace body 100 forms a high temperature environment during the smelting process, when the camera device 170 is disposed in the furnace body 100, the camera device 170 is easily damaged by the high temperature environment. In order to increase the service life of the camera device 170, in an embodiment of the present invention, the smelting arc furnace further includes a cooling structure, and the cooling structure is heat exchangeably connected to the camera device 170.

[0073] Specifically, the cooling structure includes a cooling cabin 180, the camera device 170 is disposed in the cooling cabin 180, and a cooling channel is provided in the cooling cabin 180, and the cooling channel can be used to transport carbon dioxide to cool the camera device 170. The cooling channel can be used to transport compressed carbon dioxide, so that the camera device 170 is cooled by compressed carbon dioxide, thereby reducing the ambient temperature where the camera device 170 is located, which helps to increase the service life of the camera device 170.

[0074] In an embodiment of the present invention, the smelting electric arc furnace further includes a slag port 160 provided on the furnace body 100, and the slag port 160 is used to connect to the high-level silo 740. Specifically, the slag port 160 is provided at the top of the furnace body 100. By providing the slag port 160 on the furnace body 100 and connecting to the high-level silo 740, slag such as lime and fluorite can be heated into the furnace body 100 through the slag port 160, thereby improving the convenience of conveying slag.

[0075] During the use of the smelting arc furnace, there is a gap between the furnace door 300 and the furnace body 100, and there is also a gap between the first electrode 210 and the furnace body 100, so that the outside air can easily enter the furnace body 100 through the gap. In addition, the arc generated by the first electrode 210 ionizes nitrogen in the air, and then nitrogen ions enter the molten steel, resulting in a high nitrogen content in the steel.

[0076] In order to avoid the above problems, the smelting arc furnace further includes a first gas sealing structure 510 disposed between the furnace door 300 and the furnace body 100 , and a second gas sealing structure 520 disposed between the first electrode 210 and the furnace body 100 .

[0077] The first air-sealing structure 510 can seal the gap between the furnace door 300 and the furnace body 100, preventing external air from entering the furnace body 100 through the gap between the furnace door 300 and the furnace body 100, and the second air-sealing structure 520 can seal the gap between the first electrode 210 and the furnace body 100, preventing external air from entering the furnace body 100 through the gap between the first electrode 210 and the furnace body 100, thereby ensuring a sealed environment in the furnace body 100 and facilitating the production of low-nitrogen steel.

[0078] In a feasible embodiment, the first gas sealing structure 510 includes a first gas sealing tube arranged around the periphery of the furnace door 300, the first gas sealing tube is provided with a plurality of first gas injection holes, and the first gas sealing tube is used to transport carbon dioxide; the second gas sealing structure 520 includes a second gas sealing tube arranged around the periphery of the first electrode 210, the second gas sealing tube is provided with a plurality of second gas injection holes, and the second gas sealing tube is used to transport argon. Preferably, the first gas sealing tube and the second gas sealing tube are constructed in a ring shape.

[0079] Of course, designers can adjust the specific structures of the first air-sealing structure 510 and the second air-sealing structure 520 according to usage requirements, and no specific limitation is made here.

[0080] In an embodiment of the present invention, the smelting electric arc furnace further includes a lance 190 mechanism, the lance 190 mechanism includes at least one lance 190 connected to the furnace body 100 , and the lance 190 is used to spray carbon and / or oxygen into the furnace body 100 .

[0081] Preferably, a plurality of spray guns 190 are provided, and the plurality of spray guns 190 are arranged on the furnace body 100 in a ring-like manner and placed at the lower part of the furnace body 100. Carbon and / or oxygen can be transported into the furnace body 100 through the spray guns 190.

[0082] Designers can adjust the number, arrangement and sprayed substances of the spray guns 190 according to usage requirements, and no specific restrictions are made here.

[0083] In a feasible embodiment of the present invention, the first electrode 210 includes a graphite electrode, and the graphite electrode is inserted and arranged in the furnace body 100. Specifically, the graphite electrode is vertically arranged and inserted in the furnace body 100.

[0084] Of course, in other feasible embodiments, designers can adjust the specific material of the first electrode 210 according to usage requirements, and no specific limitation is made here.

[0085] Furthermore, the electrode assembly 200 further includes a bottom electrode 220, which is disposed on the furnace body 100 and below the first electrode 210. By disposing the bottom electrode 220 on the furnace body 100, the bottom electrode 220 can better cooperate with the first electrode 210 to generate an arc, thereby improving the arc heating efficiency. Designers can adjust the specific structure and material of the bottom electrode 220 according to usage requirements, and no specific restrictions are made here.

[0086] Implementation Method 2

[0087] Please refer to Figure 1 As shown, a smelting system is also provided in an embodiment of the present invention, and the smelting system includes the smelting arc furnace described in the first embodiment.

[0088] The specific structure, working principle and beneficial effects of the smelting arc furnace are the same as those in the first embodiment, and will not be repeated here. The smelting system can reduce the amount of direct reduced iron (DRI) raw materials floating on the molten pool by using the smelting arc furnace, thereby improving the metal recovery rate of direct reduced iron (DRI), and can also achieve the production of low-nitrogen steel, thereby better realizing high-end "green steel" manufacturing.

[0089] In an embodiment of the present invention, the smelting system further includes a charging mechanism, which includes a charging hopper 610 and a charging chute 620 connecting the charging hopper 610 and the feed port 110 .

[0090] Specifically, the charging hopper 610 is disposed above the smelting arc furnace, and the charging hopper 610 is connected to the feed port 110 through the charging chute 620, so that the raw materials in the charging hopper 610 can freely fall into the furnace body 100 under the action of gravity, with better transportation efficiency.

[0091] In an embodiment of the present invention, the smelting system also includes a hot charging and hot conveying device 630, which connects the charging hopper 610 and the vertical furnace DRI outlet 640, and is used to convey the DRI raw material output from the vertical furnace DRI outlet 640 to the charging hopper 610.

[0092] The DRI raw material output from the vertical furnace DRI outlet 640 can be preheated by the hot charging and hot delivery device 630 , and the DRI raw material can be delivered to the charging hopper 610 .

[0093] Specifically, the hot charging and hot delivery device 630 includes a conveying trough 631 and a driving device 632 arranged on the conveying trough 631. The vertical furnace DRI outlet 640 is connected to one end of the conveying trough 631 through a connecting hose, and the other end of the conveying trough 631 is connected to the charging hopper 610. The driving device 632 can be used to vibrate the conveying trough 631 to transport the DRI raw material.

[0094] By using vibration conveying to transport the DRI raw material, better conveying efficiency is achieved and the problem of DRI raw material accumulating in the conveying trough 631 and causing jamming can be avoided.

[0095] Furthermore, a third gas sealing structure 530 is provided between the conveying trough 631 and the hopper 610. The third gas sealing structure 530 includes a third gas sealing pipe and a plurality of third gas injection holes provided on the third gas sealing pipe. The third gas sealing pipe is used to convey argon. Preferably, the third gas sealing pipe is constructed in an annular shape.

[0096] The third air-sealing structure 530 can seal the gap between the conveying trough 631 and the feeding hopper 610, thereby preventing external air from entering the furnace body 100 through the feed port 110, which helps to reduce the nitrogen content in the steel and achieve the production of low-nitrogen steel.

[0097] In an embodiment of the present invention, the smelting system further includes a holding mechanism, which includes a holding arm 650 and a rotating device 660 for driving the holding arm 650 to perform rotational adjustment. The holding arm 650 is connected to the feeding hopper 610 and / or the feeding chute 620.

[0098] By setting the rotating device 660, the setting direction of the holding arm 650 can be adjusted, so that the holding arm 650 can be better connected to the feeding hopper 610 and / or the feeding chute 620. In addition, by connecting the holding arm 650 with the feeding hopper 610 and / or the feeding chute 620, the holding arm 650 can support and fix the feeding hopper 610 and / or the feeding chute 620, thereby improving the structural stability of the feeding hopper 610 and / or the feeding chute 620. The designer can adjust the specific structure of the holding arm 650 and the rotating device 660 according to the use requirements, and no specific limitation is made here.

[0099] In an embodiment of the present invention, the smelting system further includes a slag hopper 710 and a slag pipe 720 connecting the slag hopper 710 and the slag port 160 . An adjustably sliding baffle 730 is provided at the outlet of the slag hopper 710 .

[0100] Specifically, the slag hopper 710 is disposed above the smelting arc furnace, and the slag hopper 710 is connected to the slag port 160 through the slag pipe 720, so that the slag in the slag hopper 710 can freely fall into the furnace body 100 under the action of gravity, with better transportation efficiency.

[0101] Furthermore, by providing an adjustable sliding baffle 730 at the outlet of the slag hopper 710, an operator can open or close the slag hopper 710 by adjusting the sliding baffle 730, thereby facilitating the conveying amount of slag and achieving a better control effect.

[0102] Furthermore, the smelting system also includes a high-level silo 740, the outlet of which is connected to the slag hopper 710, and a fourth gas sealing structure 540 is provided between the high-level silo 740 and the slag hopper 710. The fourth gas sealing structure 540 includes a fourth gas sealing pipe and a plurality of fourth jet holes arranged on the fourth gas sealing pipe, and the fourth gas sealing pipe is used to transport argon gas.

[0103] Specifically, the high-level silo 740 is disposed above the smelting arc furnace, and slag can be stored through the high-level silo 740. Designers can adjust the specific composition of the slag according to the use requirements, for example, the slag is lime, fluorite, etc., which is not specifically limited here.

[0104] In an embodiment of the present invention, the smelting system further comprises a slag overflow pipe 810 for connecting to the slag overflow port, and the slag overflow pipe 810 is arranged in an inclined manner through a bracket.

[0105] Specifically, the slag overflow port is disposed at the lower portion of the furnace body 100 , and the slag overflow pipe 810 is connected to the slag overflow port, so that the foamed slag in the furnace body 100 can be discharged through the slag overflow pipe 810 .

[0106] Furthermore, a slag pipe electromagnetic brake 820 is provided on the slag overflow pipe 810. The slag pipe electromagnetic brake 820 facilitates the control of the on-off state between the slag overflow pipe 810 and the furnace body 100.

[0107] In an embodiment of the present invention, the smelting system further includes a smoke exhaust pipe 910 for communicating with the smoke outlet 120 , and a fan 920 disposed on the smoke exhaust pipe 910 .

[0108] Specifically, the smoke exhaust pipe 910 is connected to the smoke outlet 120 through a connecting hose, and the fan 920 can drive the smoke in the furnace body 100 to be discharged along the smoke exhaust pipe 910. Designers can adjust the specific model of the fan 920 according to usage needs, and no specific limitation is made here.

[0109] Furthermore, a smoke exhaust pipe electromagnetic brake 930 is provided on the smoke exhaust pipe 910. The smoke exhaust pipe electromagnetic brake 930 facilitates the control of the on-off state between the smoke exhaust pipe 910 and the furnace body 100.

[0110] In the embodiment of the present invention, a control module is further included, and the control module is electrically connected to the slag pipe electromagnetic brake 820 and the smoke pipe electromagnetic brake 930, so that the slag pipe electromagnetic brake 820 and the smoke pipe electromagnetic brake 930 can be controlled by the control module. Designers can adjust the specific structure of the control module according to the use requirements, for example, the control module is a control circuit, a PLC controller or other control elements, which is not specifically limited here.

[0111] Furthermore, the present invention also provides a method for using a smelting system, wherein the smelting electric arc furnace in the smelting system is an 80t electric arc furnace, and specifically comprises the following steps:

[0112] Step S1: The holding arm 650 is adjusted by the rotating device 660 to connect the feeding chute 620 to the feeding port 110 .

[0113] Step S2: Turn on the slag pipe electromagnetic brake 820 and the smoke pipe electromagnetic brake 930 to connect the slag overflow pipe 810 and the smoke exhaust pipe 910 with the furnace body 100 .

[0114] Step S3: Open the first air sealing structure 510, the second air sealing structure 520, the third air sealing structure 530, and the fourth air sealing structure 540; wherein, the carbon dioxide flow rate of the first air sealing structure 510 is 0.02 L / min, the argon flow rate of the second air sealing structure 520 is 0.02 L / min, the argon flow rate of the third air sealing structure 530 is 0.06 L / min, and the argon flow rate of the fourth air sealing structure 540 is 0.2 L / min.

[0115] Step S4: Turn on the fan 920, and the air volume of the fan 920 is 1200Nm 3 / h-1300Nm 3 / h, the opening time is 10s-30s, and then closed to maintain a slight negative pressure in the furnace body 100.

[0116] Step S5: The first electrode 210 is powered on, and the hot charging and hot feeding device 630 is turned on. The feeding speed of hot DRI is 2.5 t / min-3.5 t / min, and the hot DRI enters the molten pool in the furnace body 100 through the feeding chute 620.

[0117] Step S6: Turn on the camera device 170 in the furnace body 100 to observe the state of DRI in the molten pool.

[0118] Step S7: delivering carbon dioxide through the bottom blowing port 130, with a bottom blowing flow rate of 100L / min-120L / min;

[0119] Step S8: Turn on the fan 920 again to discharge part of the high-level flue gas in the furnace body 100 to the outside of the furnace body 100;

[0120] Step S9: Open the sliding baffle 730 and add slag into the molten pool through the high-level silo 740. The slag includes but is not limited to lime, fluorite, etc.

[0121] Step S10: Turn on the spray gun 190 to blow oxygen into the molten pool in the furnace body 100 to produce foamed slag.

[0122] Step S11: When the condensation diameter of DRI in the molten pool is greater than 15 cm, lower the furnace door 300, increase the gas flow of the first gas sealing structure 510 to 10 L / min, and use the pusher head 410 to press the DRI into the molten steel for 20 seconds; then lift the pusher head 410, and after an interval of 5 to 10 minutes, when the condensation diameter of DRI in the molten pool is greater than 15 cm, use the DRI pusher head 410 to press the DRI again.

[0123] Step S12 : discharging part of the foamed slag in the furnace body 100 through the slag overflow pipe 810 .

[0124] Step S13: When approaching the end of smelting, the furnace door 300 is lowered again, the gas flow of the first gas sealing structure 510 is increased to 20 L / min, and the temperature measuring sampling gun enters the molten steel through the temperature measuring sampling port.

[0125] Step S14: When the temperature measurement is qualified, the smelting is finished, and the steel tapping port 150 is opened until the steel tapping is finished.

[0126] All articles and references disclosed, including patent applications and publications, are incorporated herein by reference for various purposes. The term "consisting essentially of ... " describing a combination should include determined elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel features of the combination. The use of the terms "comprising" or "including" to describe the combination of elements, ingredients, parts or steps here also contemplates the implementation method consisting essentially of these elements, ingredients, parts or steps. Here, by using the term "may", it is intended to illustrate that any attribute described that "may" includes is optional. Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "one" used to describe an element, ingredient, part or step is not said to exclude other elements, ingredients, parts or steps.

[0127] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be referred to each other. The above embodiments are only for illustrating the technical concept and features of the present invention. The purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A smelting arc furnace, characterized in that: include: A furnace body, wherein the furnace body is provided with a feed inlet, a smoke outlet, a bottom blowing inlet, a slag outlet and a steel outlet; An electrode assembly, the electrode assembly comprising at least one first electrode inserted and disposed in the furnace body; A furnace door, the furnace door is openably arranged on the furnace body, and the furnace door has an open position and a closed position; The pressing mechanism includes a push head and a connecting piece connected to the push head. When the furnace door is in the open position, the connecting piece can drive the push head to extend into the furnace body through the furnace door. The push head can be used to press the raw materials floating on the molten pool in the furnace body into the molten pool.

2. The smelting arc furnace according to claim 1, characterized in that: A protective layer is arranged on the pushing head.

3. The smelting arc furnace according to claim 2, characterized in that: The protective layer includes a magnesia layer arranged on the pusher head. Before the pusher head enters the furnace body, the pusher head is calcined at a calcination temperature of not less than 1200°C.

4. The smelting arc furnace according to claim 1, characterized in that: The connecting piece comprises a molten salt cooling pipe, and the molten salt cooling pipe is connected to the pusher head.

5. The smelting arc furnace according to claim 1, characterized in that: The diameter of the pusher head is 50cm-70cm, and the thickness of the pusher head is not less than 8mm.

6. The smelting arc furnace according to claim 1, characterized in that: The smelting electric arc furnace also includes a camera device arranged in the furnace body, and the camera device is used to photograph the state of the molten pool in the furnace body.

7. The smelting arc furnace according to claim 6, characterized in that: The smelting arc furnace also includes a cooling structure, and the cooling structure is connected to the camera device in a heat exchangeable manner.

8. The smelting arc furnace according to claim 7, characterized in that: The cooling structure comprises a cooling cabin, the imaging device is arranged in the cooling cabin, a cooling channel is arranged in the cooling cabin, and the cooling channel can be used to transport carbon dioxide to cool the imaging device.

9. The smelting arc furnace according to claim 1, characterized in that: The smelting electric arc furnace also includes a slag port arranged on the furnace body, and the slag port is used to connect to a high-level silo.

10. The smelting arc furnace according to claim 1, characterized in that: The smelting arc furnace further includes a first gas sealing structure arranged between the furnace door and the furnace body, and a second gas sealing structure arranged between the first electrode and the furnace body.

11. The smelting arc furnace according to claim 10, characterized in that: The first gas sealing structure includes a first gas sealing tube arranged around the periphery of the furnace door, the first gas sealing tube is provided with a plurality of first injection holes, and the first gas sealing tube is used to transport carbon dioxide; the second gas sealing structure includes a second gas sealing tube arranged around the periphery of the first electrode, the second gas sealing tube is provided with a plurality of second injection holes, and the second gas sealing tube is used to transport argon.

12. The smelting arc furnace according to claim 1, characterized in that: The smelting electric arc furnace further comprises a spray gun mechanism, wherein the spray gun mechanism comprises at least one spray gun connected to the furnace body, and the spray gun is used for spraying carbon and / or oxygen into the furnace body.

13. The smelting arc furnace according to claim 1, characterized in that: The first electrode comprises a graphite electrode, and the graphite electrode is inserted and disposed in the furnace body.

14. The smelting arc furnace according to claim 13, characterized in that: The electrode assembly further includes a bottom electrode, which is disposed on the furnace body and below the first electrode.

15. A smelting system, characterized in that: It comprises the smelting electric arc furnace as claimed in any one of claims 1 to 14.

16. The smelting system according to claim 15, characterized in that: The smelting system further comprises a feeding mechanism, which comprises a feeding hopper and a feeding chute connecting the feeding hopper and a feeding port.

17. The smelting system according to claim 16, characterized in that: The smelting system also includes a hot charging and hot conveying device, which connects the charging hopper and the DRI outlet of the vertical furnace, and is used to convey the DRI raw material output from the DRI outlet of the vertical furnace to the charging hopper.

18. The smelting system according to claim 17, characterized in that: The hot charging and hot delivery device includes a conveying trough and a driving device arranged on the conveying trough. The DRI outlet of the vertical furnace is connected to one end of the conveying trough through a connecting hose, and the other end of the conveying trough is connected to the charging hopper. The driving device can be used to vibrate the conveying trough to transport the DRI raw material. A third gas sealing structure is provided between the conveying trough and the charging hopper. The third gas sealing structure includes a third gas sealing pipe and a plurality of third gas injection holes arranged on the third gas sealing pipe. The third gas sealing pipe is used to transport argon gas.

19. The smelting system according to claim 16, characterized in that: The smelting system further comprises a holding mechanism, which comprises a holding arm and a rotating device for driving the holding arm to perform rotation adjustment, and the holding arm is connected to the feeding hopper and / or the feeding chute.

20. The smelting system according to claim 16, characterized in that: The smelting system further comprises a slag hopper and a slag pipe connecting the slag hopper and a slag port, and an outlet of the slag hopper is provided with an adjustable sliding baffle.

21. The smelting system according to claim 20, characterized in that: The smelting system also includes a high-level silo, the outlet of which is connected to the slag hopper, and a fourth gas sealing structure is provided between the high-level silo and the slag hopper. The fourth gas sealing structure includes a fourth gas sealing pipe and a plurality of fourth gas injection holes arranged on the fourth gas sealing pipe, and the fourth gas sealing pipe is used to transport argon gas.

22. The smelting system according to claim 15, characterized in that: The smelting system also includes a slag overflow pipe for connecting to the slag overflow port, and the slag overflow pipe is arranged in an inclined manner through a bracket.

23. The smelting system according to claim 22, characterized in that: The slag overflow pipe is provided with a slag pipe electromagnetic brake.

24. The smelting system according to claim 15, characterized in that: The smelting system also includes a smoke exhaust pipe for connecting to a smoke outlet, and a fan arranged on the smoke exhaust pipe.

25. The smelting system according to claim 24, characterized in that: The smoke exhaust pipe is provided with a smoke pipe electromagnetic brake.

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