A bismuth oxide production device

Abstract

The present invention relates to the field of separation technology, and specifically to a bismuth oxide production device, comprising a filter housing, an air outlet hood, a flower plate, a dust bag, a cyclone separator and an adjustment component, wherein the filter housing has an annular filter chamber inside, the air outlet hood is concentrically arranged in the annular filter chamber, and the axis of the cover body of the air outlet hood is vertical. The present invention is provided with an adjustment component, when a certain amount of nano-sized bismuth oxide powder is attached to the surface of the dust bag, the ventilation volume of the dust bag is reduced, and the air pressure inside the annular filter chamber is increased, and when the air pressure inside the annular filter chamber increases to a first preset value, the shaft is indirectly driven by the adjustment component to rotate so that the angle between the fan surface of the fan blade and the horizontal plane is reduced, thereby increasing the centrifugal force of the flue gas, making it easier to scrape off the nano-sized bismuth oxide powder attached to the surface of the dust bag, thereby slowing down the clogging speed of the dust bag, and achieving the effect of delaying the time when the dust bag is blocked to the point where it cannot be used normally.

Description

Technical Field

[0001] The invention relates to the field of separation technology, in particular to a bismuth oxide production device. Background Art

[0002] In the production process of bismuth oxide, when bismuth vapor reacts with the added air to undergo an oxidation reaction, nano-scale bismuth oxide powder is generated. Since the mass of the nano-scale bismuth oxide powder is very light, the generated nano-scale bismuth oxide powder will be mixed in the air to form flue gas and discharged from the top flue gas outlet of the reaction vessel. The discharged flue gas needs to first enter the cooler to be cooled to about 150 degrees Celsius, and then be transported to a two-stage filter for filtration. The filtration accuracy of the first-stage filter is 5 microns, and the filtration accuracy of the second-stage filter is 0.1 microns. The filtered bismuth oxide powder is collected in the filter to become a bismuth oxide product, and the filtered air can be transported to the next process for treatment.

[0003] The existing air filter used for bismuth oxide production is usually a bag filter. When the surface of the dust bag is blocked by bismuth oxide powder, it is necessary to clean the bismuth oxide powder outside the dust bag in time. Since the content of bismuth oxide powder in the flue gas is high, the dust bag needs to be cleaned frequently. To solve this problem, some technicians set a cyclone separator on the wall of the cavity of the bag filter, aiming to make the flue gas entering the cavity flow downward along the axis of the cavity in a spiral shape through the cyclone separator, so that under the action of centrifugal force, the bismuth oxide powder in the air is not easy to adhere to the outside of the dust bag. However, there are still the following problems: when the amount of bismuth oxide powder attached to the surface of the dust bag is too much, the pressure difference between the inside and outside of the dust bag will increase, so that the air pressure inside the cavity increases, and then the spiral force of the airflow entering the cavity decreases, which will accelerate the clogging speed of the dust bag. Summary of the invention

[0004] Based on this, it is necessary to provide a bismuth oxide production device to solve the problem of fast clogging of dust bags in view of the problems existing in the current flue gas filtration device used in bismuth oxide production.

[0005] The above purpose is achieved through the following technical solutions:

[0006] A bismuth oxide production device comprises:

[0007] A filter housing having an annular filter chamber therein;

[0008] An air outlet hood is concentrically arranged in the annular filter chamber, the axis of the air outlet hood is vertical, and the top of the air outlet hood passes through the filter housing;

[0009] A flower plate is concentrically arranged inside the annular filter chamber, and the flower plate separates the inside of the gas outlet hood and the inside of the annular filter chamber into two areas that are not connected to each other;

[0010] The dust bag and the upper surface of the flower plate are evenly provided with a plurality of mounting holes, and the upper part of the dust bag is arranged in the mounting holes;

[0011] The cyclone separator includes a rotating shaft and a fan blade. There are multiple rotating shafts and fan blades. The multiple rotating shafts are evenly distributed around the axis of the air outlet hood and are rotatably connected to the air outlet hood. One end of the rotating shaft passes through the air outlet hood inwardly, and the other end of the rotating shaft is fixedly connected to the fan blade.

[0012] The adjusting component is connected between the flower plate and the rotating shaft. The adjusting component is configured so that when the air pressure inside the annular filter chamber increases to a value greater than a first preset value, the rotating shaft rotates to reduce the angle between the fan surface of the fan blade and the horizontal plane.

[0013] In one embodiment, the adjustment assembly includes an inner ring, an outer ring and a fixed ring, the fixed ring is coaxially fixed on the air outlet hood, the outer ring is sleeved on the outer side of the fixed ring and can slide relative to the axis of the fixed ring, the lower part of the outer ring is arranged on the flower plate, the lower part of the inner ring is also arranged on the flower plate, and the inner ring is located on the inner side of the outer ring, a first spring is connected between the upper end of the inner ring and the air outlet hood, and a first compression spring is arranged between the outer ring and the flower plate;

[0014] The outer side of the outer ring is provided with linear friction grooves at equal intervals in the circumferential direction. The linear friction grooves correspond to the rotating shafts one by one. The linear friction grooves extend along the axis of the outer ring. One end of the rotating shaft passing through the air outlet cover is frictionally driven with the linear friction grooves.

[0015] In one embodiment, limit stops are arranged at equal intervals in the circumferential direction on the outer circumferential surface of the air outlet hood, the limit stops correspond to the rotating shafts one by one, and the limit stops are located below the rotating shaft;

[0016] When the angle between the fan surface of the fan blade and the horizontal plane increases to a first preset value, the fan blade is stopped by the limit stopper to limit the angle between the fan surface of the fan blade and the horizontal plane from continuing to increase.

[0017] In one of the embodiments, a guide slider is arranged on the outer circumference of the fixed ring, a guide groove is arranged on the inner circumference of the outer ring, and the guide slider is slidably connected in the guide groove.

[0018] In one of the embodiments, a flexible annular belt is provided between the flower plate and the air outlet hood, so that the flower plate isolates the interior of the air outlet hood and the interior of the annular filter chamber into two areas that are not connected to each other.

[0019] In one of the embodiments, a support frame is further provided inside the dust removal bag, and the upper end of the support frame is arranged on the flower plate.

[0020] In one of the embodiments, a sealing ring is provided at the connection between the dust removal bag and the mounting hole.

[0021] In one of the embodiments, a discharge port is provided at the bottom of the filter housing, and a cover plate is detachably mounted at the discharge port.

[0022] In one of the embodiments, an air outlet pipe is provided on the top of the air outlet hood.

[0023] In one of the embodiments, an air inlet pipe is arranged on the peripheral wall of the filter housing.

[0024] The beneficial effects of the present invention are:

[0025] The present invention is provided with an adjusting component. When a certain amount of nano-bismuth oxide powder is attached to the surface of the dust collector bag, the ventilation volume of the dust collector bag is reduced and the air pressure inside the annular filter chamber is increased. When the air pressure inside the annular filter chamber increases to a first preset value, the shaft is rotated through indirect driving of the adjusting component to reduce the angle between the fan surface of the fan blade and the horizontal plane. At this time, after the flue gas passes through the area where the fan blade is located, the spiral component of the flue gas along the circumference of the annular filter chamber increases, thereby increasing the centrifugal force. The increased centrifugal force, on the one hand, makes it more difficult for the nano-bismuth oxide powder in the flue gas that subsequently enters the annular filter chamber to adhere to the surface of the dust collector bag. On the other hand, when the flue gas airflow with increased centrifugal force contacts the nano-bismuth oxide powder on the surface of the dust collector bag, it is also easier to scrape off the nano-bismuth oxide powder attached to the surface of the dust collector bag, thereby slowing down the clogging speed of the dust collector bag and achieving the effect of delaying the time when the dust collector bag is blocked to the point where it cannot be used normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is an overall schematic diagram of a bismuth oxide production device of the present invention;

[0027] Figure 2 A half-section axonometric diagram of a bismuth oxide production device of the present invention;

[0028] Figure 3 for Figure 2 A schematic diagram of the enlarged structure in the middle;

[0029] Figure 4 It is a schematic structural diagram of a cyclone separator and a regulating component in a bismuth oxide production device of the present invention;

[0030] Figure 5 It is a schematic structural diagram of a gas outlet hood in a bismuth oxide production device of the present invention;

[0031] Figure 6 The production flow chart of bismuth oxide is shown below;

[0032] Figure 7 It is a structural schematic diagram of a reactor in a bismuth oxide production device of the present invention;

[0033] Figure 8 The figure is a schematic diagram of the positions of the first air channel and the second air channel in a bismuth oxide production device of the present invention.

[0034] in:

[0035] 100, filter housing; 110, annular filter chamber; 120, discharge port; 130, cover plate; 140, air outlet pipe; 150, air inlet pipe; 200, air outlet cover; 210, limit stopper; 220, rotating hole; 300, flower plate; 310, mounting hole; 320, flexible ring belt; 400, dust bag; 410, supporting frame; 500, cyclone separator; 510, rotating shaft; 520, fan blade; 600, adjustment component; 610, inner ring; 620, outer ring; 621, linear friction groove ; 630, fixing ring; 640, first spring; 650, first compression spring; 1000, reactor; 1100, cathode; 1200, cathode terminal; 1300, feed inlet; 1400, shell; 1500, refractory material layer; 1601, first air valve; 1602, second air valve; 1700, anode terminal; 1800, anode; 1901, first air channel; 1902, second air channel; 2000, heat exchanger; 3000, induced draft fan; 4000, collector. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0037] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0038] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0039] like Figure 1-Figure 8 As shown, a bismuth oxide production device includes a filter housing 100, an air outlet hood 200, a flower plate 300, a dust bag 400, a cyclone separator 500 and an adjustment component 600. The filter housing 100 has an annular filter chamber 110 inside, the air outlet hood 200 is concentrically arranged in the annular filter chamber 110, the hood body part of the air outlet hood 200 has a vertical axis, and the top of the air outlet hood 200 passes through the filter housing 100, the flower plate 300 is concentrically arranged inside the annular filter chamber 110, and the flower plate 300 isolates the inside of the air outlet hood 200 and the inside of the annular filter chamber into two areas that are not connected to each other, the upper surface of the flower plate 300 is evenly provided with a plurality of mounting holes 310, the upper part of the dust bag 400 is arranged in the mounting hole 310, and the cyclone separator 500 is provided with a plurality of mounting holes 310. The separator 500 includes a rotating shaft 510 and a fan blade 520. There are multiple rotating shafts 510 and fan blades 520. The multiple rotating shafts 510 are evenly distributed around the axis of the air outlet hood 200 and are rotatably connected to the air outlet hood 200. Specifically, rotating holes 220 are circumferentially evenly spaced on the outer circumferential surface of the air outlet hood 200. The rotating shaft 510 passes through the rotating holes 220 to achieve one end of the rotating shaft 510 passing through the air outlet hood 200 inwardly, and the other end of the rotating shaft 510 is fixedly connected to the fan blade 520. The adjustment component 600 is connected between the flower plate 300 and the rotating shaft 510. The adjustment component 600 is configured so that after the air pressure inside the annular filter chamber 110 increases to be greater than the first preset value, the rotation of the rotating shaft 510 can reduce the angle between the fan surface of the fan blade 520 and the horizontal plane.

[0040] It should be further explained that an air outlet pipe 140 is disposed on the top of the air outlet hood 200 , and the air outlet pipe 140 is used to transport the flue gas containing nano-sized bismuth oxide powder into the annular filter chamber 110 .

[0041] It should be further explained that an air inlet pipe 150 is disposed on the peripheral wall of the filter housing 100 , and the air inlet pipe 150 is used to discharge the smoke after filtering the nano-sized bismuth oxide powder.

[0042] When in use, the staff connects the flue gas input pipe for conveying nano-sized bismuth oxide powder to the exhaust pipe 140, connects the intake pipe 150 to the flue gas output pipe, and then opens the valves of the flue gas input pipe and the flue gas output pipe to convey the flue gas containing nano-sized bismuth oxide powder into the annular filter chamber 110. When the flue gas entering the annular filter chamber 110 passes through the area where the fan blade 520 is located, the fan surface of the fan blade 520 is set at an angle to the horizontal plane, so the flue gas passes through the area where the fan blade 520 is located. After the dust removal bag 400 is completed, the air passes through the dust removal bag 400 and enters the exhaust hood 200. The nano-sized bismuth oxide powder remains on the outside of the dust removal bag 400. As the smoke spirals downward, the nano-sized bismuth oxide in the smoke is not easily attached to the outside of the dust removal bag 400 under the action of centrifugal force. Therefore, the dust removal bag 400 can be used normally for a longer time. After a certain amount of nano-sized bismuth oxide powder is attached to the surface of the dust bag 400, the ventilation volume of the dust bag 400 is reduced, and the air pressure inside the annular filter chamber 110 is increased. When the air pressure inside the annular filter chamber 110 increases to a first preset value, the shaft 510 is rotated by the indirect drive of the adjustment component 600 so that the angle between the fan surface of the fan blade 520 and the horizontal plane is reduced. At this time, after the smoke passes through the area where the fan blade 520 is located, the spiral component force of the smoke along the circumference of the annular filter chamber 110 increases, thereby The centrifugal force is increased. On the one hand, the increased centrifugal force makes it more difficult for the nano-bismuth oxide powder in the flue gas that subsequently enters the annular filter chamber 110 to adhere to the surface of the dust bag 400. On the other hand, when the flue gas flow with increased centrifugal force comes into contact with the nano-bismuth oxide powder on the surface of the dust bag 400, it is also easier to scrape off the nano-bismuth oxide powder attached to the surface of the dust bag 400, thereby slowing down the clogging speed of the dust bag 400 and achieving the effect of delaying the time when the dust bag 400 is blocked to the point where it cannot be used normally.

[0043] It should also be noted that when the rotating shaft 510 rotates so that the angle between the fan surface of the fan blade 520 and the horizontal plane decreases, the air flow cross-section of the area where the fan blade 520 is located is reduced. When the flue gas input flow rate remains unchanged, the flue gas flow rate increases when the flue gas passes through the area where the fan blade 520 is located, that is, the kinetic energy increases, which is more conducive to reducing the amount of nano-bismuth oxide powder attached to the dust bag 400.

[0044] In a further embodiment, Figure 3As shown, the adjustment assembly 600 includes an inner ring 610, an outer ring 620 and a fixed ring 630. The fixed ring 630 is coaxially fixed on the air outlet cover 200. The outer ring 620 is sleeved on the outer side of the fixed ring 630 and can slide relative to the axis of the fixed ring 630. The lower part of the outer ring 620 is arranged on the flower plate 300. The lower part of the inner ring 610 is also arranged on the flower plate 300, and the inner ring 610 is located on the inner side of the outer ring 620. A first spring 640 is connected between the upper end of the inner ring 610 and the air outlet hood 200, a first compression spring 650 is provided between the outer ring 620 and the flower plate 300, and linear friction grooves 621 are provided at equal intervals on the outer side of the outer ring 620 in the circumferential direction. The linear friction grooves 621 correspond to the rotating shaft 510 one by one, and the linear friction grooves 621 extend along the axis of the outer ring 620. The end of the rotating shaft 510 that passes through the air outlet hood 200 is frictionally transmitted with the linear friction grooves 621.

[0045] When the air pressure inside the annular filter chamber 110 increases to a first preset value, under the action of air pressure, the flower plate 300 is forced to move upward along its axis, and the first compression spring 650 is first compressed. After the first compression spring 650 is compressed a certain distance, the flower plate 300, the inner ring 610 and the outer ring 620 move upward along the axis of the flower plate 300 synchronously. At this time, the first spring 640 begins to be compressed. Since the outer side of the outer ring 620 is circumferentially evenly spaced with linear friction grooves 621, and the linear friction grooves 621 are rubbed with the rotating shaft 510, the outer ring 620 moves downward to drive the rotating shaft 510 to rotate, and the rotating shaft 510 drives the fan blade 520 to rotate, so that the rotating shaft 510 rotates to reduce the angle between the fan surface of the fan blade 520 and the horizontal plane, so that after the smoke passes through the area where the fan blade 520 is located, the spiral component of the smoke along the circumference of the annular filter chamber 110 increases.

[0046] It should be supplemented that, in the present invention, a pulse jet device should be provided inside the air outlet hood 200 and at the top of the bag opening of the dust bag 400, for pulse jetting in the reverse direction to the inside of the dust bag 400, so that the nano-sized bismuth oxide powder outside the dust bag 400 is separated from the outside of the dust bag 400. During the pulse jetting, the staff needs to close the valves of the flue gas input pipe and the flue gas output pipe in sequence, at which time the air pressure inside the annular filter chamber 110 is reduced, and the flower plate 300 moves downward, at which time the distance between the dust bag 400 and the bottom of the annular filter chamber 110 is closer, and the pulse device is started to jet into the dust bag 400, so that the nano-sized bismuth oxide particles on the surface of the dust bag 400 are shaken off, and since the dust bag 400 is closer to the bottom of the annular filter chamber 110 at this time, the shaken off dust is more likely to quickly gather at the bottom of the annular filter chamber 110, and will not float in the annular filter chamber 110 for a long time.

[0047] In a further embodiment, Figure 2 and Figure 5 As shown, limit stops 210 are arranged at equal intervals in the circumferential direction on the outer circumferential surface of the air outlet hood 200, the limit stops 210 correspond to the rotating shaft 510 one by one, and the limit stops 210 are located below the rotating shaft 510. When the angle between the fan surface of the fan blade 520 and the horizontal plane increases to a first preset value, the fan blade 520 and the limit stops 210 are stopped to limit the angle between the fan surface of the fan blade 520 and the horizontal plane from continuing to increase.

[0048] The limit stopper 210 is provided to limit the maximum angle between the fan surface of the fan blade 520 and the horizontal plane by stopping the fan blade 520 with the limit stopper 210, so as to prevent the angle between the fan surface of the fan blade 520 and the horizontal plane from being too large, resulting in the spiral component of the smoke being too small when the smoke flows to the area where the fan blade 520 is located.

[0049] In a further embodiment, Figure 3 As shown, a flexible annular belt 320 is provided between the flower plate 300 and the gas outlet hood 200, so that the flower plate 300 isolates the inside of the gas outlet hood 200 and the inside of the annular filter chamber 110 into two areas that are not connected to each other.

[0050] A flexible annular belt 320 is provided to connect the flower plate 300 and the gas outlet hood 200 , and the inside of the gas outlet hood 200 and the inside of the annular filter chamber 110 are isolated into two mutually disconnected areas under the premise that the flower plate 300 can move relative to the gas outlet hood 200 .

[0051] In a further embodiment, Figure 2 As shown, a support frame 410 is further provided inside the dust removal bag 400 , and the upper end of the support frame 410 is arranged on the flower plate 300 .

[0052] The support frame 410 is used to support the dust bag 400 to prevent the dust bag 400 from being excessively deformed when the pressure difference between the inside and outside of the dust bag 400 is too large.

[0053] In a further embodiment, a sealing ring is provided at the connection between the dust removal bag 400 and the mounting hole 310 .

[0054] A sealing ring is provided at the connection between the dust removal bag 400 and the mounting hole 310 to enhance the sealing performance and prevent air leakage at the connection between the dust removal bag 400 and the mounting hole 310 .

[0055] In a further embodiment, Figure 2 As shown, a discharge port 120 is provided at the bottom of the filter housing 100, and a cover plate 130 is detachably mounted at the discharge port 120. Specifically, the cover plate 130 can be hinged at the discharge port 120 or can be screwed at the discharge port 120.

[0056] The discharge port 120 is provided to take out the filtered and separated nano-sized bismuth oxide powder from the annular filtering chamber 110 .

[0057] In a further embodiment, a guide slider is provided on the outer circumference of the fixed ring, a guide groove is provided on the inner circumference of the outer ring, and the guide slider is slidably connected in the guide groove.

[0058] The cooperation between the guide sliding block and the guide sliding groove is used to guide the axial movement of the outer ring relative to the fixed ring.

[0059] Bismuth oxide Bismuth trioxide is a bismuth compound with a light yellow powder appearance. Bismuth oxide is used in electronics, chemical industry, glass manufacturing, inorganic synthesis, catalysts, coatings, high-temperature superconductors, medicine and other fields. In the field of electronics, bismuth oxide is mainly used to produce varistors, thermistors, cathode ray tubes, zinc oxide lightning arresters, etc. In the field of chemical industry, bismuth oxide can be used to manufacture chemical reagents, bismuth salts, etc.; in the field of coatings, bismuth oxide can be used to produce anti-corrosion coatings, automotive coatings, etc.

[0060] Bismuth oxide can be divided into industrial grade and electronic grade, among which electronic grade bismuth oxide has higher purity requirements, requiring a purity of more than 99.5%. The production process of bismuth oxide is divided into wet process and pyrometallurgical process. The process flow of pyrometallurgy: refined bismuth → melting → atomization incineration → bismuth oxide collection → product grading. The pyrometallurgical process has high energy consumption and high pollution. Under the background of stricter environmental protection policies, the pyrometallurgical process will gradually be eliminated by the market. Wet process flow: refined bismuth → melting → water quenching → nitric acid dissolution → solution concentration and crystallization → crystallization calcination → bismuth oxide. At present, most domestic bismuth oxide manufacturers use wet nitric acid system to produce bismuth oxide, but a lot of nitrate pollution occurs due to the introduction of nitric acid medium during the production process.

[0061] The device for producing bismuth oxide of the present invention does not involve nitric acid environmental pollution and does not produce by-products during the production process of bismuth oxide. The production process is free of environmental pollution, and the product can reach an electronic grade purity of more than 99.5%.

[0062] The principle of the invention is that in the reactor, a DC plasma arc is used to generate a high temperature of about 5000°C to melt and evaporate the metal bismuth to form metal bismuth vapor, which reacts with the air to generate nano-bismuth oxide. The device is characterized in that the particles of the metal bismuth are smaller in the gasified state, and the contact with the air is more complete, and the generated bismuth oxide is fine and uniform.

[0063] Reaction principle: Bismuth vapor and air undergo oxidation reaction under high temperature conditions to produce bismuth trioxide.

[0064] The generated bismuth oxide particles are carried by the air, forming flue gas that flows out of the reactor from the top. The mixture of bismuth oxide and air passes through a cooler and is cooled to 150°C. The cooled flue gas enters a two-stage filter, with the first stage filtration accuracy of ≤5μm and the second stage filtration accuracy of ≤0.01μm. The bismuth metal powder obtained by filtration is collected, packaged and sold as a product, and the filtered air is discharged into the atmosphere by an exhaust fan.

[0065] The device of the present invention is composed of a reactor 1000, a heat exchanger 2000, a filter, an induced draft fan 3000 and a collector 4000.

[0066] The shell 1400 (reactor) is composed of two cylindrical barrels as the main body, connected by a 45° conical barrel in the middle. The height of the conical barrel is 500mm. The diameter of the upper cylinder is 2.5 times that of the lower cylinder. The lower part is the melting / evaporation area of ​​metal bismuth, and the upper part is the bismuth oxidation area. The diameter of the upper cylinder is 0.8-1.5 meters. The top of the reactor is an elliptical head cover. The reactor shell is made of metal. There is a refractory layer 1500 inside. The refractory layer is 40-60mm thick and made of Al2O3 corundum casting material. A graphite bottom electrode is installed at the bottom of the reactor. The graphite electrode is provided with a connector for an external DC power supply. The bottom electrode is an anode 1800, which is connected to the positive pole of the power supply during operation. The top head cover is provided with a feed inlet 1300, an electrode insertion port, and a flue gas outlet. The feed port can be used to put in batches of raw materials, and the electrode insertion port is used to allow the electrode to be raised into the furnace. The inserted electrode is the cathode 1100, which forms a loop with the anode at the bottom of the furnace during operation, generating a high-temperature plasma arc to melt the metal bismuth and gasify it into steam. In the conical area of ​​the reactor, two air channels are provided, namely the first air channel 1901 and the second air channel 1902. The first air channel 1901 and the second air channel 1902 are used to introduce air to react with bismuth vapor. The channels are 180 degrees symmetrically arranged, and the angle between the center line of the air channel and the center axis is 4 degrees. This design is to ensure that when air is introduced, the symmetrically added air can form a vortex state in the furnace, so that the air is fully in contact with the bismuth vapor, and the residence time of the air in the reactor is extended to achieve a good reaction effect. The air pressure is 10Kpa, and a control valve is provided to control the air flow entering the reactor.

[0067] The top electrode of the reactor is the cathode 1100, which passes through the top of the reactor and is close to the bottom anode. An electrode adjustment device is provided on the reactor shell. The function of the electrode adjustment device is to fix the cathode electrode and drive the electrode up and down under the control of the servo motor, thereby changing the distance between the cathode and the anode in the reactor. A high-voltage DC cable is provided on the adjustment device to connect the negative pole of the external power supply.

[0068] Implementation steps:

[0069] S100: Add metal bismuth oxide raw material from the feed port at the top of the reactor, and close the feed door after the addition is completed.

[0070] S200: Connect high-voltage direct current to the electrodes, with the anode terminal 1700 connected to the positive pole of the direct current, and the cathode terminal 1200 connected to the negative pole of the direct current, and the applied direct current voltage is 0-150V.

[0071] S300: The distance between the cathode and the bottom electrode is adjusted by 0.1-1mm through the servo motor-driven electrode moving device, and the DC voltage is adjusted to break through the air insulation layer of the electrode head, forming a stable DC plasma arc at the cathode head. The plasma arc can generate a high temperature of more than 5000℃, melt the added metal bismuth into liquid and vaporize it to form metal bismuth vapor. The liquid level of the melted metal bismuth shall not exceed the height of the air channel inlet.

[0072] S400: Open the air valve to allow air to flow into the reactor from the two lower channels simultaneously, forming a vortex rising state in the furnace.

[0073] S500: During the rising process, the bismuth vapor encounters the added air and undergoes an oxidation reaction to generate nano-sized bismuth oxide powder.

[0074] S600: The generated bismuth oxide powder is extremely light in weight. After mixing with air, it forms flue gas and flows out from the flue gas outlet at the top of the reactor. The flue gas out of the reactor enters the cooler and is cooled to 150 degrees.

[0075] S700: The cooled flue gas enters a two-stage filter, the first stage filter has a filtration accuracy of 5μm, and the second stage filter has a filtration accuracy of 0.1μm. The filtered bismuth oxide particles are collected and sold as bismuth oxide products, and the filtered air is directly discharged into the atmosphere.

[0076] S800: When the reaction of the metal bismuth is completed, the next batch of feeding operation can be carried out, and the cycle is repeated.

[0077] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A bismuth oxide production device, characterized in that: include: A filter housing having an annular filter chamber therein; An air outlet hood is concentrically arranged in the annular filter chamber, the axis of the air outlet hood is vertical, and the top of the air outlet hood passes through the filter housing; A flower plate is concentrically arranged inside the annular filter chamber, and the flower plate separates the inside of the gas outlet hood and the inside of the annular filter chamber into two areas that are not connected to each other; The dust bag and the upper surface of the flower plate are evenly provided with a plurality of mounting holes, and the upper part of the dust bag is arranged in the mounting holes; The cyclone separator includes a rotating shaft and a fan blade. There are multiple rotating shafts and fan blades. The multiple rotating shafts are evenly distributed around the axis of the air outlet hood and are rotatably connected to the air outlet hood. One end of the rotating shaft passes through the air outlet hood inwardly, and the other end of the rotating shaft is fixedly connected to the fan blade. An adjusting component, the adjusting component is connected between the flower plate and the rotating shaft, and the adjusting component is configured so that after the air pressure inside the annular filter chamber increases to be greater than a first preset value, the rotating shaft rotates to reduce the angle between the fan surface of the fan blade and the horizontal plane. The adjusting component includes an inner ring, an outer ring and a fixed ring, the fixed ring is coaxially fixed on the air outlet hood, the outer ring is sleeved on the outer side of the fixed ring and the outer ring can slide relative to the axis of the fixed ring, the lower part of the outer ring is arranged on the flower plate, the lower part of the inner ring is also arranged on the flower plate, and the inner ring is located on the inner side of the outer ring, a first spring is connected between the upper end of the inner ring and the air outlet hood, and a first compression spring is arranged between the outer ring and the flower plate; The outer side of the outer ring is provided with linear friction grooves at equal intervals in the circumferential direction, the linear friction grooves correspond to the rotating shafts one by one, the linear friction grooves extend along the axis of the outer ring, and the end of the rotating shaft passing through the air outlet cover is frictionally driven with the linear friction grooves, and the outer circumferential surface of the air outlet cover is provided with limit stops at equal intervals in the circumferential direction, the limit stops correspond to the rotating shafts one by one, and the limit stops are located below the rotating shaft; When the angle between the fan surface of the fan blade and the horizontal plane increases to a first preset value, the fan blade is stopped by the limit stopper to limit the angle between the fan surface of the fan blade and the horizontal plane from continuing to increase.

2. A bismuth oxide production device according to claim 1, characterized in that: A guide slide block is arranged on the outer circumference of the fixed ring, a guide slide groove is arranged on the inner circumference of the outer ring, and the guide slide block is slidably connected in the guide slide groove.

3. A bismuth oxide production device according to claim 1, characterized in that: A flexible annular belt is arranged between the flower plate and the air outlet hood, so that the flower plate isolates the inside of the air outlet hood and the inside of the annular filter chamber into two areas which are not connected to each other.

4. A bismuth oxide production device according to claim 1, characterized in that: A support frame is also provided inside the dust removal bag, and the upper end of the support frame is arranged on the flower plate.

5. A bismuth oxide production device according to claim 1, characterized in that: A sealing ring is provided at the connection between the dust removal bag and the mounting hole.

6. A bismuth oxide production device according to claim 1, characterized in that: A discharge port is arranged at the bottom of the filter housing, and a cover plate is detachably mounted at the discharge port.

7. A bismuth oxide production device according to claim 1, characterized in that: An air outlet pipe is arranged on the top of the air outlet hood.

8. The bismuth oxide production device according to claim 1, characterized in that: An air inlet pipe is arranged on the peripheral wall of the filter housing.

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