Magnesium metal vacuum smelting furnace and using method thereof

Abstract

The invention provides a magnesium metal vacuum smelting furnace and a using method thereof.The smelting furnace comprises a tank body and a tank cover, a crucible and a splash-proof cover are arranged in the tank body, and a liquid ferrosilicon heat preservation input mechanism, a residue siphon discharging mechanism and a residual iron discharging mechanism are arranged at the bottom of the tank body; and a powder spraying gun mounting mechanism and a slag breaking and sampling gun mounting mechanism are arranged on the tank cover. According to the invention, the liquid ferrosilicon reducing agent can be ensured not to be solidified during input, and residues after reduction reaction can be smoothly discharged, so that the powder spraying gun and the slag breaking sampling gun are stably and firmly mounted and stably run.

Description

Technical Field

[0001] The present invention relates to the technical field of metal smelting, and more specifically, to a magnesium vacuum smelting furnace and a method for using the same. Background Art

[0002] Magnesium is one of the most abundant light metal elements on earth, with an abundance of 2% in the earth's crust. China is the country with the richest magnesium resources in the world. Magnesium resources are of various types and widely distributed. Solid ores mainly include magnesite, dolomite, serpentine, etc. Magnesium is a green metal material in the 21st century. It is used in the form of magnesium alloys. It has the advantages of high specific strength, light weight, shock absorption, good cutting processability, etc. It is widely used in metallurgy, aerospace, transportation, military industry, batteries and other fields.

[0003] At present, the main method of magnesium smelting in China is the Pijiang process, which uses external flame heating as the heating method, with a thermal efficiency of 10%-30% and a single-unit production capacity of 3.5t-6t / day. It has defects such as high energy consumption, high pollution and low yield. Some companies use the vertical tank method, which uses internal resistance heating as the heating method, with a thermal efficiency of 65%-85% and a single-unit production capacity of 320-460kg tank / day. It has problems such as tank wall adhesion and heating body adhesion.

[0004] Liquid magnesium smelting by injection is a new type of magnesium smelting technology. The process is to heat under a certain vacuum and temperature to melt ferrosilicon into a liquid reduction pool. The magnesium-containing raw materials are sprayed into the reduction pool with argon gas to produce a controllable reduction reaction. The technical process equipment is relatively mature, the reaction speed is fast, and it has the potential for large-scale production. It has high thermal efficiency, low cost, and environmental protection. It is the mainstream development direction of magnesium smelting in the future.

[0005] However, the existing magnesium smelting furnace has high energy consumption, low product purity, ferrosilicon reducing agent easily blocks the input pipeline, the residue and residual iron after the reduction reaction cannot be discharged well, the powder spraying gun and slag sampling gun are not firmly fixed vertically and the operation is unstable, resulting in high magnesium smelting cost and low efficiency. Summary of the invention

[0006] In view of the above problems, the purpose of the present invention is to provide a magnesium vacuum smelting furnace, which can ensure that the liquid ferrosilicon reducing agent will not cool down and solidify when it is input, the residue and iron after the reduction reaction can be discharged smoothly, and the powder spraying gun and the slag sampling gun are firmly fixed vertically and operate stably.

[0007] The present invention provides a magnesium vacuum smelting furnace, comprising a tank body and a tank cover buckled on the tank body, a crucible arranged at the bottom of the tank body and a splash-proof cover buckled on the crucible, and further comprising:

[0008] The liquid ferrosilicon heat preservation input mechanism comprises a liquid ferrosilicon built-in channel arranged upward from the bottom of the crucible, wherein the liquid ferrosilicon built-in channel passes through the bottom of the tank body and is connected to the ferrosilicon heat preservation delivery pipeline arranged outside the bottom of the tank body;

[0009] A residue siphon discharge mechanism, comprising a residue discharge built-in channel arranged upward from the bottom of the crucible, the residue discharge built-in channel passes through the bottom of the tank body and is connected to a residue siphon discharge pipe arranged outside the bottom of the tank body, a transparent viewing port is arranged on the pipe wall of the residue siphon discharge pipe, and a cover is arranged at the port of the residue siphon discharge pipe;

[0010] A powder spray gun installation mechanism, comprising a powder spray gun installation sleeve arranged on one side of the central surface of the tank cover and a powder spray gun guide sleeve arranged on the splash-proof cover, wherein the powder spray gun installation sleeve and the powder spray gun guide sleeve are connected and vertically penetrated;

[0011] The slag sampling gun installation mechanism comprises a slag sampling gun installation sleeve arranged on the other side of the center plane of the tank cover and a slag sampling gun guide sleeve arranged on the splash cover, wherein the slag sampling gun installation sleeve and the slag sampling gun guide sleeve are connected and vertically penetrated;

[0012] The residual iron discharging mechanism is arranged at the bottom of the tank body and is used for discharging the residual iron after smelting.

[0013] The pipeline wall of the ferrosilicon insulation transportation pipeline comprises a heat-resistant stainless steel layer, a carbon felt layer and a graphite layer arranged in sequence from the outside to the inside, and a heating device is arranged outside the ferrosilicon insulation transportation pipeline.

[0014] The residue siphoning and discharging pipeline includes a first vertical pipe and a second vertical pipe connected to the bottom of the tank body by flanges and bolts, a horizontal pipe is detachably connected between the lower ends of the first vertical pipe and the second vertical pipe, the first vertical pipe is longer than the second vertical pipe, a downwardly inclined inclined pipe is detachably connected to the upper end of the first vertical pipe, the transparent viewing port is arranged at the upper part of the first vertical pipe, and the cover body is arranged at the end of the inclined pipe; the pipeline wall of the residue siphoning and discharging pipeline includes a heat-resistant stainless steel layer, a carbon felt layer and a refractory brick layer which are arranged in sequence from the outside to the inside.

[0015] The tank body includes a steel cylinder and a steel bottom arranged at the bottom of the steel cylinder. The steel cylinder includes annular steel walls connected in sequence, and a circle of reinforcing ribs are respectively arranged at the upper and lower joints of adjacent annular steel walls; a refractory brick layer and a carbon fiber felt layer are laid in sequence from the inside to the outside on the inner side of the steel cylinder, and a brick layer is laid on the steel bottom; a tank body flange is arranged around the upper end of the steel cylinder, and a tank cover flange matched with the tank body flange is arranged around the tank cover.

[0016] A flange water cooling device and a safety explosion-proof device are provided on the tank body. The flange water cooling device includes a water gas pipe arranged around the lower side of the tank flange. The water inlet end of the water gas pipe is connected to the water supply system, and the water outlet end of the water gas pipe is connected to the vacuum water cooling box, and the vacuum water cooling box is connected to the external water cooling box. A pneumatic ball valve is provided at the water inlet end of the water gas pipe; the safety explosion-proof device includes two groups of vacuum pressure release valves arranged in the middle and lower part of the tank body, and an integrated temperature transmitter is provided on the tank body. The temperature measuring probe of the integrated temperature transmitter extends into the interior of the tank body; an openable and closable inspection door is provided at the lower end of the tank body.

[0017] A residual iron discharge mechanism is arranged at the bottom of the tank body, and the residual iron discharge mechanism comprises a residual iron discharge port opened at the bottom of the crucible, and the residual iron discharge port is connected to a sliding water port arranged at the bottom of the tank body.

[0018] The crucible is a graphite crucible, and a heating mechanism is arranged outside the crucible. The heating mechanism includes an induction coil surrounding the lower half of the crucible, carbon felt is laid between the induction coil and the crucible, and the induction coil is connected to a power source outside the tank.

[0019] An observation window is arranged on the tank cover, and the observation window includes a through-tube that is commonly penetrated on the crucible and the tank cover, and glass is arranged on the upper end of the through-tube, one of the observation windows is arranged vertically, and the angle between the other observation window and the vertical direction is 30°; a magnesium vapor outlet pipe with an angle of 10° to the horizontal plane is arranged on the upper part of the tank body, and the magnesium vapor outlet pipe is connected to the magnesium vapor outlet on the crucible.

[0020] Three splash-proof cover hoisting devices are evenly arranged around the tank cover, and the splash-proof cover hoisting device includes a chain guide sleeve vertically arranged on the tank cover, a guide sleeve flange is arranged on the outer periphery of the upper end of the chain guide sleeve, a ring plate is arranged on the inner periphery of the upper end of the chain guide sleeve, two connecting plates symmetrical about the central plane of the ring plate are arranged on the ring plate, and a first pin is connected between the two connecting plates; three lifting ears are evenly arranged around the splash-proof cover, and the lifting ears include two ear plates arranged on the splash-proof cover and a second pin connected between the two ear plates, a ring chain is connected between the first pin and the second pin, and the ring chain is located in the chain guide sleeve; a sleeve cover is buckled on the upper part of the chain guide sleeve, and the sleeve cover flange of the sleeve cover is connected to the guide sleeve flange by bolts.

[0021] Another aspect of the present invention provides a method for using a magnesium metal vacuum smelting furnace, which uses the magnesium metal vacuum smelting furnace to perform smelting, comprising the following steps:

[0022] S1: hoisting the tank cover, wherein the splash-proof cover is located below the tank cover through the connection of the splash-proof cover hoisting device, buckling the splash-proof cover above the crucible, and buckling the tank cover above the tank body;

[0023] S2: installing the powder spray gun and the powder spray gun guide sleeve, and installing the slag sampling gun and the slag sampling gun installation sleeve;

[0024] S3: evacuating the tank and the crucible;

[0025] S4: transporting liquid ferrosilicon into the ferrosilicon insulation transport pipeline, the liquid ferrosilicon enters the crucible along the liquid ferrosilicon built-in channel, turning on the powder spraying gun to spray powder into the crucible, and turning on the heating mechanism to heat the crucible;

[0026] S5: Observe the transparent viewing port on the residue siphon discharge pipe. If there is residue in the transparent viewing port, open the cover body, and the residue flows through the residue discharge built-in channel to the residue siphon discharge pipe and flows out;

[0027] S6: After the smelting cycle is completed, the sliding water nozzle is opened to discharge the residual iron.

[0028] From the above description, it can be known that the magnesium vacuum smelting furnace and the method of using the same provided by the present invention include a liquid ferrosilicon heat preservation input mechanism, so that the liquid ferrosilicon reducing agent will not cool down and solidify, and can be smoothly input into the smelting furnace; when the liquid ferrosilicon reducing agent reaches a certain liquid level, the residue floating on the surface can be automatically and smoothly discharged, and the amount of residue can be checked through the transparent viewing port on the residue siphon discharge mechanism, and the flow of the residue can be checked during slag discharge to determine whether there is residue blockage; the residual iron discharge mechanism opens the sliding water outlet to automatically discharge residual iron when the furnace is shut down for maintenance; the powder spray gun installation mechanism can make the powder spray gun installed vertically and stably, the slag sampling gun installation mechanism can make the slag sampling gun installed vertically and stably, and the residual iron discharge mechanism can smoothly discharge residual iron. The structure of the present invention can improve the efficiency of magnesium smelting and reduce smelting costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] By referring to the following description in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other objects and results of the present invention will become more apparent and easy to understand. In the accompanying drawings:

[0030] Figure 1 is a cross-sectional view of a magnesium vacuum smelting furnace according to Example 1 of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of a residue siphon discharge pipeline according to Example 1 of the present invention;

[0032] Figure 3is a cross-sectional view of a tank body according to Embodiment 1 of the present invention;

[0033] Figure 4 is a side sectional view of a tank body according to Embodiment 1 of the present invention;

[0034] Figure 5 is a cross-sectional view of a can cover according to Embodiment 1 of the present invention;

[0035] Figure 6 is a cross-sectional view of a splash-proof cover according to Embodiment 1 of the present invention;

[0036] Figure 7 Schematic diagram of the structure of a splash-proof cover hoisting device according to Embodiment 1 of the present invention;

[0037] Figure 8 This is a flow chart of a method for using a magnesium vacuum smelting furnace according to Example 2 of the present invention;

[0038] Among them, 1-tank body, 11-steel cylinder, 12-reinforcement ring rib plate, 13-refractory brick layer, 14-carbon fiber felt layer, 15-magnesia carbon brick layer, 16-high alumina brick layer, 17-tank body flange, 18-magnesium steam outlet pipe, 19-feeding port;

[0039] 2-tank cover, 21-tank cover flange, 22-observation window, 23-powder spray gun installation sleeve, 24-slag sampling gun installation sleeve;

[0040] 3-crucible, 31-heating mechanism, 311-induction coil, 312-carbon felt;

[0041] 4-splash cover, 41-splash cover hoisting device, 411-chain guide sleeve, 412-guide sleeve flange, 413-ring plate, 414-connecting plate, 415-first pin, 416-lifting ear, 4161-ear plate, 4162-second pin, 417-ring chain, 418-cover, 419-cover flange, 42-powder spray gun guide sleeve, 43-slag sampling gun guide sleeve;

[0042] 5-liquid ferrosilicon insulation input mechanism, 51-liquid ferrosilicon internal channel, 52-ferrosilicon insulation delivery pipeline, 53-heating device;

[0043] 6-residue siphon discharge mechanism, 61-residue discharge built-in channel, 62-residue siphon discharge pipeline, 621-first vertical pipe, 622-second vertical pipe, 623-horizontal pipe, 624-oblique pipe, 63-transparent viewing port, 64-cover body;

[0044] 7- Flange water cooling device;

[0045] 8-Safety explosion-proof device, 81-Vacuum pressure relief valve, 82-Integrated temperature transmitter;

[0046] 9- Inspection door;

[0047] 10-residual iron discharge mechanism, 101-sliding water nozzle;

[0048] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0049] The present invention can be subjected to various changes and can have various embodiments, and specific embodiments are illustrated and described in the accompanying drawings. However, the present invention is not limited to the specific implementation, and all changes, equivalents and substitutes falling within the concept and technical scope of the present invention are included, and should be understood to be included.

[0050] Ordinal terms such as first, second, etc. may be used to describe various constituent elements, but the constituent elements are not limited to the terms. The terms are only used to distinguish one constituent element from another constituent element. For example, without departing from the scope of the claims of the present invention, the second constituent element may be named as the first constituent element, and similarly, the first constituent element may be named as the second constituent element. The terms and / or include a combination of multiple associated items or a certain item among multiple associated items.

[0051] It should be understood that when a certain component is mentioned to be "connected" or "contacted" with other components, this includes not only the case where it is directly connected or contacted with other components, but also the case where other components exist in between. Conversely, when a certain component is mentioned to be "directly connected" or "directly contacted" with other components, it should be understood that there are no other components in between.

[0052] In the description of the embodiments, when it is described that a certain component is formed "on or under" another component, on or under includes two components directly contacting each other or at least one other component is arranged and formed between the two components. Moreover, when it is expressed as on or under, it refers to not only the upper direction but also the lower direction based on a certain component.

[0053] The terms used in this application are only used to illustrate specific embodiments and are not intended to limit the present invention. Unless the context clearly provides otherwise, singular expressions include plural expressions. In this application, it should be understood that terms such as "including" or "having" are used to specify the presence of features, numbers, steps, operations, constituent elements, parts or combinations thereof recorded in the specification, and do not preclude the presence or additional possibility of one or more other features, numbers, steps, operations, constituent elements, parts or combinations thereof.

[0054] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as those generally understood by those skilled in the art. Terms defined in commonly used dictionaries should be interpreted as having the same meaning as in the context of the relevant technology, and if not clearly defined in this application, they should not be interpreted as ideal or overly formal meanings.

[0055] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0056] Example 1

[0057] like Figure 1-Figure 7 As shown in the figure, the magnesium metal vacuum smelting furnace proposed in this embodiment can be used for the smelting of magnesium metal and can also be used for the smelting of other metals.

[0058] This magnesium vacuum smelting furnace adopts liquid injection method to smelt magnesium. The powder spray gun sprays calcined white powder into the smelting furnace. The calcined white powder reacts with the liquid ferrosilicon reducing agent to generate the residue after the reaction and magnesium vapor. The magnesium vapor is collected. The residue floats on the surface of the molten pool formed by the liquid ferrosilicon reducing agent. When the residue reaches a certain amount, it should be discharged in time, otherwise it will affect the smelting efficiency. If the liquid ferrosilicon reducing agent cannot be supplied smoothly, it will also affect the smelting efficiency. The use of this magnesium vacuum smelting furnace can make the residue discharged smoothly and in time, and can also smoothly provide liquid ferrosilicon.

[0059] The magnesium metal vacuum smelting furnace comprises a tank body 1 and a tank cover 2 buckled on the tank body 1. The tank body 1 and the tank cover 2 are evacuated by a vacuum pump to form a vacuum space to maintain a vacuum smelting environment.

[0060] A crucible 3 and a splash cover 4 buckled on the crucible 3 are provided at the bottom of the tank body 1. The crucible 3 and the splash cover 4 form a vacuum reaction chamber, and the ferrosilicon reducing agent in the crucible 3 is heated outside the crucible 3 to keep the liquid to form a molten pool, and chemically react with the calcined white powder. The splash cover 4 is used to block the splashed residue and ferrosilicon in the reaction chamber so that they will not splash into the tank body 1, and at the same time prevent the magnesium vapor generated by the reaction from diffusing.

[0061] In order to ensure that the liquid ferrosilicon enters the crucible 3 quickly, smoothly and uninterruptedly, a liquid ferrosilicon insulation input mechanism 5 is provided at the bottom of the tank body 1. The high-temperature liquid ferrosilicon transported by external equipment passes through the insulation input mechanism before entering the crucible 3, which can prevent the liquid ferrosilicon from cooling and solidifying and clogging the input pipeline.

[0062] In order to transport the liquid ferrosilicon to the optimal position in the crucible 3 and improve the chemical reaction efficiency, the liquid ferrosilicon insulation input mechanism 5 may include a liquid ferrosilicon built-in channel 51 arranged upward from the bottom of the crucible 3, and the liquid ferrosilicon built-in channel 51 passes through the bottom of the tank body 1 and is connected to the ferrosilicon insulation delivery pipeline 52 arranged on the outside of the bottom of the tank body 1.

[0063] The height of the liquid ferrosilicon built-in channel 51 is determined according to the smelting conditions, and the wall surface of the liquid ferrosilicon built-in channel 51 from the inside to the outside can be refractory bricks and graphite. The liquid ferrosilicon built-in channel 51 is connected to the bottom of the crucible 3 and to the bottom of the tank body 1, so as to be connected to the ferrosilicon insulation conveying pipeline 52 outside the tank body 1. The ferrosilicon insulation conveying pipeline 52 is connected to an external liquid ferrosilicon storage device, etc. to obtain liquid ferrosilicon. The ferrosilicon insulation conveying pipeline 52 has the function of heat preservation to prevent the liquid ferrosilicon from cooling and solidifying during transportation.

[0064] In order to discharge the residue smoothly, a residue siphon discharge mechanism 6 is provided at the bottom of the tank body 1 . When there is too much residue and it needs to be discharged, the residue siphon discharge mechanism 6 is opened and the residue is discharged to the outside of the tank body 1 .

[0065] The residue siphon discharge mechanism 6 may include a residue discharge built-in channel 61 arranged upward from the bottom of the crucible 3, the residue discharge built-in channel 61 passes through the bottom of the tank body 1 and is connected to a residue siphon slag discharge pipe 62 arranged on the outer side of the bottom of the tank body 1, a transparent viewing port 63 is arranged on the uppermost tube wall of the residue siphon slag discharge pipe 62, and a cover body 64 is arranged at the end of the residue siphon slag discharge pipe 62.

[0066] The material of the residue discharge internal channel 61 can be refractory bricks and graphite from the inside to the outside, and the residue discharge internal channel 61 is connected to the bottom of the crucible 3 and to the bottom of the tank body 1, so as to be connected to the residue siphon discharge pipeline 62 outside the tank body 1. The residue siphon discharge pipeline 62 is connected to an external residue collection device to collect the discharged residue.

[0067] The residue siphon discharge mechanism 6 discharges the residue by the principle of siphon. The height of the residue discharge internal channel 61 is determined according to the smelting conditions and can be the same height as the liquid ferrosilicon internal channel 51.

[0068] When slag discharge is required, the vacuum of the smelting furnace is appropriately released, and the cover 64 can be opened. The residue enters the higher residue discharge built-in channel 61 under the action of gravity, and is discharged from the lower residue siphon slag discharge pipe 62.

[0069] The transparent viewing port 63 can be used to check whether there is any residue, and to observe the flow of the residue during the slag discharge. If the liquid residue does not flow, it means that the residue has blocked the residue siphon discharge pipe 62 and needs to be manually processed in time. After the processing, the residue can be discharged smoothly.

[0070] In order to stably install the powder spray gun, a powder spray gun mounting mechanism is arranged on the top of the tank cover 2. The powder spray gun mounting mechanism may include a powder spray gun mounting sleeve 23 arranged on one side of the central surface of the tank cover 2 and a powder spray gun guide sleeve 42 arranged on the splash-proof cover 4. The powder spray gun mounting sleeve 23 and the powder spray gun guide sleeve 42 are opposite to each other up and down, and are vertically connected after being connected.

[0071] The powder spray gun can enter the crucible 3 in the channel formed by the powder spray gun mounting sleeve 23 and the powder spray gun guide sleeve 42, and the operation is stable, and dust will not be brought into the tank body 1, thereby preventing magnesium products from entering the induction coil area.

[0072] In order to stably install the slag sampling gun, a slag sampling gun mounting mechanism is arranged on the top of the tank cover 2. The slag sampling gun mounting mechanism may include a slag sampling gun mounting sleeve 24 arranged on the other side of the center plane of the tank cover 2 and a slag sampling gun guide sleeve 43 arranged on the splash-proof cover 4. The slag sampling gun mounting sleeve 24 and the slag sampling gun guide sleeve 43 are opposite to each other up and down, and are vertically connected after being connected.

[0073] The slag sampling gun can enter the crucible 3 in the channel formed by the slag sampling gun installation sleeve 24 and the slag sampling gun guide sleeve 43, and the operation is stable, and the residue will not be brought into the tank body 1, so as to prevent the magnesium product from entering the induction coil area.

[0074] Specifically, the lower end of the powder spray gun mounting sleeve 23 is between the tank cover 2 and the splash cover 4 and is connected to the powder spray gun guide sleeve 42 through a flange and bolts, and the lower end of the slag sampling gun mounting sleeve 24 is between the tank cover 2 and the splash cover 4 and is connected to the slag sampling gun guide sleeve 43 through a flange and bolts. The parts of the powder spray gun mounting sleeve 23 and the slag sampling gun mounting sleeve 24 located below the tank cover 2 are both provided with bellows to alleviate thermal displacement under high temperature conditions.

[0075] The residual iron discharge mechanism 10 is arranged at the bottom of the tank body 1 and is used for automatically discharging the reduced residual iron during shutdown inspection or after smelting.

[0076] In a specific embodiment of the present invention, in order to keep the input ferrosilicon in liquid state, the pipe wall of the ferrosilicon insulation delivery pipe 52 includes a heat-resistant stainless steel layer, a carbon felt layer and a graphite layer arranged in sequence from the outside to the inside, and a heating device 53 is arranged outside the ferrosilicon insulation delivery pipe 52 for heating. The connection between the ferrosilicon insulation delivery pipe 52 and the tank body 1 should be sealed to prevent air from entering.

[0077] The graphite layer is in contact with the liquid ferrosilicon, and the graphite layer and the carbon felt layer play a role in heat preservation. The heat-resistant stainless steel layer is in contact with the heating device 53, and the heating device 53 can further ensure the temperature of the liquid ferrosilicon to prevent solidification.

[0078] In a specific embodiment of the present invention, in order to facilitate the discharge of residue, the residue siphon discharge pipe 62 includes a first vertical pipe 621 and a second vertical pipe 622 connected to the bottom of the tank body 1 by flanges and bolts, and a horizontal pipe 623 is detachably connected between the lower ends of the first vertical pipe 621 and the second vertical pipe 622. The first vertical pipe 621 is longer than the second vertical pipe 622, and a downwardly inclined inclined pipe 624 is detachably connected to the upper end of the first vertical pipe 621. The transparent viewing port 63 is arranged at the upper part of the first vertical pipe 621, and the cover body 64 is arranged at the end of the inclined pipe 624.

[0079] As the smelting process progresses, when the residue in the crucible 3 reaches a certain height, it will enter the residue discharge built-in channel 61 by its own gravity, and then enter the residue siphon discharge pipe 62. If the residue can be seen in the transparent viewing port 63, it means that there is a lot of residue and it is necessary to discharge the residue. When the cover 64 is opened, the first vertical pipe 621 is much lower than the residue discharge built-in channel 61, which triggers a siphon effect, sucking the residue out and entering the residue collection device. When opening the cover 64, it is necessary to release the vacuum appropriately so that the cover 64 can be opened. During the residue discharge process, the residue siphon discharge pipe 62 is full of residue, which will not affect the vacuum degree in the crucible 3.

[0080] If the residue is seen to flow very slowly or not at all in the transparent viewing port 63 during the residue discharge process, it means that there is sticky residue on the pipe wall of the residue siphon discharge pipe 62, which hinders the discharge of the residue. The first vertical pipe 621, the horizontal pipe 623, the second vertical pipe 622, and the inclined pipe 624 are all detachably connected, which can be easily disassembled to remove the sticky residue and the remaining residue, and prevent the sticky residue from clogging the pipe. The residue siphon discharge pipe 62 should be cleaned after each smelting.

[0081] The pipe wall of the residue siphoning and discharging pipe 62 includes heat-resistant stainless steel, carbon felt and refractory bricks arranged in sequence from the outside to the inside. The pipe wall formed by the refractory bricks, carbon felt and heat-resistant stainless steel can withstand the high temperature of the residue and isolate the high temperature of the residue from the outside.

[0082] In a specific embodiment of the present invention, the tank body 1 may include a steel cylinder 11 and a steel bottom arranged at the bottom of the steel cylinder 11, and the material may be Q355 steel. The steel cylinder 11 includes annular steel walls connected in sequence, which may be four in this embodiment, and a circle of reinforcing ribs 12 are respectively arranged at the upper and lower joints of adjacent annular steel walls, a carbon fiber felt layer 14 and a refractory brick layer 13 are laid in sequence on the inner wall of the steel cylinder 11 from the outside to the inside, and a magnesium carbon brick layer 15 and a high aluminum brick layer 16 are laid in sequence on the steel bottom from the bottom to the top, a tank body flange 17 is arranged around the upper end of the steel cylinder 11, and a tank cover flange 21 adapted to the tank body flange 17 is arranged around the tank cover 2.

[0083] The tank cover 2 is buckled on the tank body 1, and the tank body flange 17 and the tank cover flange 21 are tightly fitted together by vacuuming, and can be directly hoisted and transported away after breaking the vacuum.

[0084] The tank body 1 is a tall cylindrical shape, and the reinforcing ring rib plate 12 can strengthen the combination of the annular steel wall and the internal carbon fiber felt layer 14 and the refractory brick layer 13, so that the structure is firm.

[0085] The outer wall of the tank body 1 is made of steel to ensure the vacuum degree. The internal refractory brick layer 13 can withstand the high temperature of thousands of degrees during smelting. The carbon fiber felt layer 14 has the characteristics of heat resistance, acid resistance, alkali resistance, etc., which can keep the heat and isolate the high temperature in the furnace from being transmitted to the outside. The high-alumina brick layer 16 at the bottom has high thermal stability, a refractoriness of more than 1770℃, and good slag resistance, which is suitable for the lining of the tank body 1. The lightweight magnesia carbon brick layer 15 has good insulation and fire resistance, and good thermal shock resistance. The tank bottom formed by the two layers of bricks has good stability.

[0086] In a specific embodiment of the present invention, in order to ensure safe smelting, a flange water cooling device 7 and a safety explosion-proof device 8 are provided on the tank body 1. The flange water cooling device 7 includes a water gas pipe arranged on the lower side of the tank body flange 17. The water inlet end of the water gas pipe is connected to the water supply system, the water outlet end of the water gas pipe is connected to the vacuum water cooling box, the vacuum water cooling box is connected to the external water cooling collection box, and a pneumatic ball valve is provided at the water inlet end of the water gas pipe.

[0087] The water-gas pipe is a high-temperature resistant water pipe. After passing cold water, the tank flange 17 can be cooled, thereby cooling the tank cover flange 21. The water flowing out of the water-gas pipe is high-temperature water heated by the high temperature of the tank flange 17. The high-temperature water first flows into the vacuum water cooling box to reduce the water temperature to a certain extent, and then flows into the external water cooling box to further reduce the water temperature. The pneumatic ball valve can control the opening and closing of the water inlet end of the water-gas pipe.

[0088] The safety explosion-proof device 8 may include two sets of vacuum pressure release valves 81 arranged in the middle and lower part of the tank body 1. When the temperature and vacuum degree are abnormal, appropriate vacuum can be released through the vacuum pressure release valves 81 to protect safety.

[0089] In order to know the temperature in the tank body 1 in real time, an integrated temperature transmitter 82 may be provided on the tank body 1, and the temperature measuring probe of the integrated temperature transmitter 82 extends into the interior of the tank body 1. The temperature in the tank body 1 may be observed externally through a display connected to the integrated temperature transmitter 82.

[0090] In order to maintain and repair the equipment in the tank body 1 after shutdown, an openable and closable inspection door 9 is provided at the lower end of the tank body 1. The inspection door 9 should be sealed with the tank body 1 wall after closing.

[0091] In a specific embodiment of the present invention, in order to discharge the residual iron liquid in the crucible 3 after smelting is completed, a residual iron discharge mechanism 10 is provided at the bottom of the tank body 1, and the residual iron discharge mechanism 10 includes a residual iron discharge port opened at the bottom of the crucible 3, and the residual iron discharge port is connected to a sliding water gate 101 arranged at the bottom of the tank body 1.

[0092] After the smelting is completed, the vacuum is released, and the sliding water gate 101 can accurately adjust the flow rate of the residual iron flowing out of the crucible 3, so that the residual iron is discharged stably and safely.

[0093] In a specific embodiment of the present invention, the crucible 3 is a graphite crucible, and a heating mechanism 31 is arranged outside the crucible 3. The heating mechanism 31 includes an induction coil 311 surrounding the lower half of the crucible 3, and a carbon felt 312 is laid between the induction coil 311 and the crucible 3. The induction coil 311 is connected to a power source outside the tank body 1.

[0094] After the induction coil 311 is powered on, the reaction material in the crucible 3 can be heated to a set temperature. The 50 mm thick carbon felt 312 separates the induction coil 311 and the crucible 3 to prevent the induction coil 311 from being damaged by overheating.

[0095] In a specific embodiment of the present invention, in order to observe the slag and molten pool in the crucible 3, an observation window 22 is provided on the tank cover 2, and the observation window 22 includes a through-tube that is commonly penetrated on the crucible 3 and the tank cover 2, and glass is provided at the upper end of the through-tube. One observation window 22 is vertically arranged, and the angle between the other observation window 22 and the vertical direction is 30°.

[0096] The situation in the crucible 3 can be observed through the observation windows 22. One observation window 22 can be vertically arranged near the center point of the tank cover 2, and the other observation window 22 can be arranged between the upper observation window 22 and the edge of the tank cover 2 and toward the center of the crucible 3. The two observation windows 22 can fully observe the situation in the crucible 3.

[0097] In order to collect magnesium vapor, a magnesium vapor outlet pipe 18 with an angle of 10° with the horizontal plane is provided on the upper part of the tank body 1, and the magnesium vapor outlet pipe 18 is connected to the magnesium vapor outlet on the crucible 3. The magnesium vapor outlet pipe 18 slightly inclined upward is connected to a vacuum magnesium collection device to collect the smelted magnesium vapor.

[0098] A feeding port 19 is also provided on the upper part of the tank body 1. The feeding port 19 is connected to a feeding port on the crucible 3. The feeding port 19 receives feeding from the vacuum silo. The feeding may be for replenishing ferrosilicon.

[0099] In a specific embodiment of the present invention, in order to connect the tank cover 2 with the splash cover 4, three splash cover hoisting devices 41 are evenly arranged around the tank cover 2. The three splash cover hoisting devices 41 connect the tank cover 2 with the splash cover 4, and the splash cover 4 can be hoisted at the same time when the tank cover 2 is hoisted.

[0100] The splash-proof cover hoisting device 41 includes a chain guide sleeve 411 vertically arranged on the tank cover 2, the chain guide sleeve 411 is connected to the inside of the tank cover 2, a guide sleeve flange 412 is arranged on the outer periphery of the upper end of the chain guide sleeve 411, a ring plate 413 is arranged on the inner periphery of the upper end of the chain guide sleeve 411, two connecting plates 414 symmetrical about the center plane of the ring plate 413 are arranged on the ring plate 413, a first pin shaft 415 is connected between the two connecting plates 414, the first pin shaft 415 passes through the holes on the two connecting plates 414, and is fixed by a cotter pin.

[0101] The ring plate 413 and the guide sleeve flange 412 may be an integral annular flange plate.

[0102] Three lifting ears 416 are evenly arranged around the splash cover 4, and the three lifting ears 416 correspond to the three chain guide sleeves 411 respectively. The lifting ears 416 may include two ear plates 4161 and a second pin shaft 4162 connected between the two ear plates 4161, and the second pin shaft 4162 passes through the holes on the two ear plates 4161 and is fixed by a split pin. The split pin fixation can facilitate the disassembly of the splash cover 4.

[0103] The first pin 415 and the second pin 4162 are respectively used as connection points on the tank cover 2 and the splash cover 4, and a ring chain 417 is connected between the first pin 415 and the second pin 4162, and the ring chain 417 is inserted into the chain guide sleeve 411. The ring chain 417 is a ring formed by a chain.

[0104] In order to ensure the vacuum in the tank body 1, during the smelting process, a cover 418 is buckled on the upper part of the chain guide sleeve 411, and a cover flange 419 of the cover 418 is connected to the guide sleeve flange 412 by bolts. The cover 418 is a cover body 64 with the same cross section as the chain guide sleeve 411, and a cover flange 419 matching the guide sleeve flange 412 is arranged on the edge of the cover body 64. After the cover 418 is installed on the chain guide sleeve 411, the chain guide sleeve 411 can be closed.

[0105] An internal guide sleeve may also be provided inside the chain guide sleeve 411, the upper end of the internal guide sleeve is connected to the inner ring of the ring plate 413, and the lower end is passed through the tank cover 2. The upper half of the ring chain 417 is limited in the internal guide sleeve, and the ring chain 417 is basically vertical when the tank cover 2 is lifted, so that the splash cover 4 can be lifted stably without shaking.

[0106] The splash cover 4 may include a cover body 64 made of stainless steel 2520 and a heat-resistant concrete cover lining from top to bottom.

[0107] The magnesium metal vacuum smelting furnace improves the stability, safety, product purity and smelting efficiency of liquid magnesium smelting by injection method.

[0108] Example 2

[0109] like Figure 8 As shown, the method for using a magnesium vacuum smelting furnace proposed in this embodiment uses the magnesium vacuum smelting furnace described in Example 1 to perform smelting, including the following steps:

[0110] S1: The tank cover 2 is hoisted, the splash-proof cover 4 is connected to the bottom of the tank cover 2 by the splash-proof cover hoisting device 41, the splash-proof cover 4 is buckled on the top of the crucible 3, and the tank cover 2 is buckled on the top of the tank body 1.

[0111] First, install the tank cover 2, and use the lifting equipment to lift the tank cover 2. The tank cover 2 and the splash cover 4 are connected up and down into one piece through the splash cover lifting device 41. When lifting the tank cover 2, the splash cover 4 is also lifted, which is convenient for installation. Buckle the splash cover 4 on the crucible 3, and buckle the tank cover 2 on the tank body 1, without bolt connection.

[0112] S2: Install the powder spray gun and the powder spray gun mounting sleeve 23, and install the slag sampling gun and the slag sampling gun mounting sleeve 24.

[0113] After the cover is installed, install the powder spray gun and the slag sampling gun. Hoist the powder spray gun, and connect the lower mounting pipe of the powder spray gun with the powder spray gun mounting sleeve 23 through a flange and bolts. Hoist the slag sampling gun, and connect the lower mounting pipe of the slag sampling gun with the slag sampling gun mounting sleeve 24 through a flange and bolts.

[0114] S3: Evacuate the tank 1 and the crucible 3.

[0115] After all parts are installed, a sealed space is formed and vacuuming begins. After the tank body 1 and the crucible 3 are vacuumed by a vacuum pump, the tank cover 2 and the tank body 1 are tightly buckled, and the splash-proof cover 4 and the crucible 3 are tightly buckled.

[0116] S4: Liquid ferrosilicon is transported to the ferrosilicon insulation transport pipe 52, and the liquid ferrosilicon enters the crucible 3 along the liquid ferrosilicon built-in channel 51. The powder spraying gun is turned on to spray powder into the crucible 3, and the heating mechanism 31 is turned on to heat the crucible.

[0117] When smelting starts, liquid ferrosilicon is transported to the ferrosilicon insulation transport pipeline 52 from an external liquid ferrosilicon storage device. Since the ferrosilicon insulation transport pipeline 52 has an insulation function, it can prevent the liquid ferrosilicon from cooling and solidifying during transportation, so that the liquid ferrosilicon can be transported quickly and smoothly.

[0118] The powder spraying gun sprays powder into the molten pool formed by liquid ferrosilicon, and a chemical reaction occurs to generate magnesium vapor, which is output from the tank body through the magnesium vapor outlet pipe 18 and collected to finally obtain magnesium.

[0119] The heating mechanism 31 provides high temperature for the chemical reaction.

[0120] S5: Observe the transparent viewing port 63 on the residue siphon discharge pipe 62. If there is residue at the transparent viewing port 63, open the cover 64, and the residue flows through the residue discharge built-in channel 61 to the residue siphon discharge pipe 62 and flows out.

[0121] The slag siphoning and discharging pipe 62 may include a first vertical pipe 621 and a second vertical pipe 622 connected to the bottom of the tank body 1 by flanges and bolts. A horizontal pipe 623 is detachably connected between the lower ends of the first vertical pipe 621 and the second vertical pipe 622. The first vertical pipe 621 is longer than the second vertical pipe 622. A downwardly inclined inclined pipe 624 is detachably connected to the upper end of the first vertical pipe 621. A transparent viewing port 63 is arranged at the upper part of the first vertical pipe 621, and a cover body 64 is arranged at the end of the inclined pipe 624.

[0122] As the smelting process progresses, when the residue in the crucible 3 reaches a certain height, it will enter the residue discharge built-in channel 61 by its own gravity, and then enter the residue siphon discharge pipe 62. If there is residue at the transparent viewing port 63, it means that there is a lot of residue and it is necessary to discharge the residue. When the cover 64 is opened, the first vertical pipe 621 is much lower than the residue discharge built-in channel 61, which triggers a siphon effect, sucking the residue out and entering the residue collection device. When opening the cover 64, it is necessary to release the vacuum appropriately so that the cover 64 can be opened. During the residue discharge process, the residue siphon discharge pipe 62 is full of residue, which will not affect the vacuum degree in the crucible 3.

[0123] If the residue is seen to flow very slowly or not at all in the transparent viewing port 63 during the residue discharge process, it means that there is sticky residue on the pipe wall of the residue siphon discharge pipe 62, which hinders the discharge of the residue. The first vertical pipe 621, the horizontal pipe 623, the second vertical pipe 622, and the inclined pipe 624 are all detachably connected, which can be easily disassembled to remove the sticky residue and the remaining residue, and prevent the sticky residue from clogging the pipe. The residue siphon discharge pipe 62 should be cleaned after each smelting.

[0124] S6: After the smelting cycle is completed, the sliding water gate 101 is opened to discharge the residual iron.

[0125] The above describes the magnesium vacuum smelting furnace and the method for using the same according to the present invention by way of example with reference to the accompanying drawings. However, those skilled in the art should understand that various improvements can be made to the magnesium vacuum smelting furnace and the method for using the same according to the present invention without departing from the content of the present invention. Therefore, the protection scope of the present invention should be determined by the content of the attached claims.

Claims

1. A magnesium vacuum smelting furnace, comprising a tank body and a tank cover buckled on the tank body, a crucible arranged at the bottom of the tank body and a splash-proof cover buckled on the crucible, characterized in that: Also includes: The liquid ferrosilicon heat preservation input mechanism comprises a liquid ferrosilicon built-in channel arranged upward from the bottom of the crucible, wherein the liquid ferrosilicon built-in channel passes through the bottom of the tank body and is connected to the ferrosilicon heat preservation delivery pipeline arranged outside the bottom of the tank body; A residue siphon discharge mechanism, comprising a residue discharge built-in channel arranged upward from the bottom of the crucible, the residue discharge built-in channel passes through the bottom of the tank body and is connected to a residue siphon discharge pipe arranged outside the bottom of the tank body, a transparent viewing port is arranged on the pipe wall of the residue siphon discharge pipe, and a cover is arranged at the port of the residue siphon discharge pipe; A powder spray gun installation mechanism, comprising a powder spray gun installation sleeve arranged on one side of the central surface of the tank cover and a powder spray gun guide sleeve arranged on the splash-proof cover, wherein the powder spray gun installation sleeve and the powder spray gun guide sleeve are connected and vertically penetrated; The slag sampling gun installation mechanism comprises a slag sampling gun installation sleeve arranged on the other side of the center plane of the tank cover and a slag sampling gun guide sleeve arranged on the splash cover, wherein the slag sampling gun installation sleeve and the slag sampling gun guide sleeve are connected and vertically penetrated; The residual iron discharging mechanism is arranged at the bottom of the tank body and is used for discharging the residual iron after smelting.

2. The magnesium vacuum smelting furnace according to claim 1, characterized in that: The pipeline wall of the ferrosilicon insulation transportation pipeline comprises a heat-resistant stainless steel layer, a carbon felt layer and a graphite layer arranged in sequence from the outside to the inside, and a heating device is arranged outside the ferrosilicon insulation transportation pipeline.

3. The magnesium vacuum smelting furnace according to claim 1, characterized in that: The residue siphoning and discharging pipeline comprises a first vertical pipe and a second vertical pipe connected to the bottom of the tank body by flanges and bolts, a horizontal pipe is detachably connected between the lower ends of the first vertical pipe and the second vertical pipe, the first vertical pipe is longer than the second vertical pipe, a downwardly inclined inclined pipe is detachably connected to the upper end of the first vertical pipe, the transparent viewing port is arranged at the upper part of the first vertical pipe, and the cover body is arranged at the end of the inclined pipe; The pipe wall of the residue siphoning and discharging pipe comprises a heat-resistant stainless steel layer, a carbon felt layer and a refractory brick layer which are arranged in sequence from the outside to the inside.

4. The magnesium vacuum smelting furnace according to claim 1, characterized in that: The tank body comprises a steel cylinder and a steel bottom arranged at the bottom of the steel cylinder, the steel cylinder comprises annular steel walls connected in sequence, and a circle of reinforcing rib plates are respectively arranged above and below the connection of adjacent annular steel walls; A refractory brick layer and a carbon fiber felt layer are sequentially laid on the inner side of the steel cylinder from the inside to the outside, and a brick layer is laid on the steel bottom; A tank body flange is arranged around the upper end of the steel cylinder, and a tank cover flange matched with the tank body flange is arranged around the tank cover.

5. The magnesium vacuum smelting furnace according to claim 4, characterized in that: A flange water cooling device and a safety explosion-proof device are provided on the tank body. The flange water cooling device includes a water gas pipe provided around the lower side of the tank body flange. The water inlet end of the water gas pipe is connected to the water supply system, the water outlet end of the water gas pipe is connected to the vacuum water cooling box, the vacuum water cooling box is connected to the external water cooling box, and a pneumatic ball valve is provided at the water inlet end of the water gas pipe; The safety explosion-proof device comprises two sets of vacuum pressure release valves arranged at the middle and lower part of the tank body, an integrated temperature transmitter is arranged on the tank body, and the temperature measuring probe of the integrated temperature transmitter extends into the interior of the tank body; An openable and closable inspection door is arranged at the lower end of the tank body.

6. The magnesium vacuum smelting furnace according to claim 1, characterized in that: The residual iron discharge mechanism comprises a residual iron discharge port opened at the bottom of the crucible, and the residual iron discharge port is connected to a sliding water port arranged at the bottom of the tank body.

7. The magnesium vacuum smelting furnace according to claim 1, characterized in that: The crucible is a graphite crucible, and a heating mechanism is arranged outside the crucible. The heating mechanism includes an induction coil surrounding the lower half of the crucible, carbon felt is laid between the induction coil and the crucible, and the induction coil is connected to a power source outside the tank.

8. The magnesium vacuum smelting furnace according to claim 1, characterized in that: An observation window is provided on the tank cover, and the observation window comprises a through-tube which is commonly provided on the crucible and the tank cover, and a glass is provided on the upper end of the through-tube, wherein one observation window is vertically provided, and the angle between the other observation window and the vertical direction is 30°; A magnesium vapor outlet pipe with an angle of 10° with the horizontal plane is arranged on the upper part of the tank body, and the magnesium vapor outlet pipe is connected to the magnesium vapor outlet on the crucible.

9. The magnesium vacuum smelting furnace according to claim 1, characterized in that: Three splash cover hoisting devices are evenly arranged on the tank cover, and the splash cover hoisting device includes a chain guide sleeve vertically arranged on the tank cover, a guide sleeve flange is arranged on the outer periphery of the upper end of the chain guide sleeve, a ring plate is arranged on the inner periphery of the upper end of the chain guide sleeve, two connecting plates symmetrical about the center plane of the ring plate are arranged on the ring plate, and a first pin is connected between the two connecting plates; Three lifting ears are evenly arranged on the splash cover, and the lifting ears include two ear plates arranged on the splash cover and a second pin connected between the two ear plates. A ring chain is connected between the first pin and the second pin, and the ring chain is located in the chain guide sleeve; A sleeve cover is buckled on the upper part of the chain guide sleeve, and the sleeve cover flange of the sleeve cover is connected with the guide sleeve flange through bolts.

10. A method for using a magnesium vacuum smelting furnace, using the magnesium vacuum smelting furnace as claimed in any one of claims 1 to 9 for smelting, characterized in that: The following steps are involved: S1: hoisting the tank cover, wherein the splash-proof cover is located below the tank cover through the connection of the splash-proof cover hoisting device, buckling the splash-proof cover above the crucible, and buckling the tank cover above the tank body; S2: installing the powder spray gun on the powder spray gun mounting sleeve, and installing the slag sampling gun on the slag sampling gun mounting sleeve; S3: evacuating the tank and the crucible; S4: transporting liquid ferrosilicon into the ferrosilicon insulation transport pipeline, the liquid ferrosilicon enters the crucible along the liquid ferrosilicon built-in channel, turning on the powder spraying gun to spray powder into the crucible, and turning on the heating mechanism to heat the crucible; S5: Observe the transparent viewing port on the residue siphoning and discharging pipe. If there is residue in the transparent viewing port, open the cover body, and the residue flows to the residue siphoning and discharging pipe through the residue discharge built-in channel and flows out. S6: After the smelting cycle is completed, the sliding water nozzle is opened to discharge the residual iron.

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