Shaft furnace magnesium reduction composite tank structure

Abstract

The invention discloses a shaft furnace magnesium reduction composite tank body structure which comprises a composite tank body (5) and is characterized in that a bell jar valve (6) and a crystallizer (7) are arranged on the lower portion in the composite tank body (5), the composite tank body (5) comprises an outer tank (51), an inner tank (52), a distribution rib plate (53), a closing-in section (54), a supporting plate (55), a slag discharging barrel (56) and a flange (57), the inner tank (52) is connected with the outer tank (51) through the distribution rib plate (53), holes are evenly distributed in the inner tank (52) to guide magnesium steam, and the flange (57) is connected with the outer tank (51) through the supporting plate (55). A supporting plate (55) is arranged at the bottom of the outer tank (51), and the outer tank (51) is connected with a deslagging cylinder (56) and a flange (57) below the supporting plate (55); the inner wall of the bottom of the outer tank (51) is connected with an inclined closing section (54), and the bottom of the closing section (54) is connected with a slag discharging cylinder (56). The structure is easy to manufacture, stable in use performance, long in service life, low in implementation cost, rapid and uniform in heat transfer, small in radiation heat loss and low in operation and maintenance cost, and the product quality and productivity are guaranteed.

Description

Technical Field

[0001] This invention relates to a composite tank structure for a vertical shaft magnesium reduction furnace, belonging to the field of thermal magnesium smelting technology. Background Technology

[0002] Currently, vertical shaft furnace reduction technology is gradually becoming popular in the thermal (Pidgeon process) magnesium smelting production. Its principle is to utilize the low boiling point of magnesium under vacuum conditions, reducing magnesium vapor with ferrosilicon under high temperature and vacuum, then drawing it out and cooling it to obtain metallic magnesium ingots. Existing technologies are divided into two types: "top-outlet magnesium, bottom-outlet slag" and "bottom-outlet magnesium, bottom-outlet slag." However, both generally suffer from the following drawbacks: 1. The tank and the central cylinder only contact at the top and bottom ends. Heat is mainly transferred from the tank shell to the material and then to the central cylinder, with the central cylinder contributing very little to heat transfer, resulting in slow and uneven heat transfer; 2. The high-temperature tank deforms severely, leading to a short lifespan; 3. During loading and unloading, the central cylinder and tank suffer significant radiative heat loss, resulting in high energy consumption; 4. Slag removal is inefficient and labor-intensive. Clearly, the existing technologies are not ideal.

[0003] In the prior art, Chinese patent CN221279960U discloses a magnesium reduction furnace, including a support frame, a furnace body, a cooling and collecting device, and a slag discharge chamber. The furnace body is mounted on the support frame, the cooling and collecting device is located at the top of the furnace body, and the slag discharge chamber is located at the bottom of the furnace body. A heat insulation layer is provided on the outer side of the furnace body, and a heating device is provided between the furnace body and the heat insulation layer. The heating device includes multiple microwave generators, which are evenly distributed around the side walls of the furnace body. This application uses microwave generators to heat the furnace body and uses a heat insulation layer for insulation, reducing heat loss, lowering energy consumption, avoiding the use of fuel for heating, and reducing the generation of pollutants. However, this furnace body has problems such as slow heat transfer, easy deformation of the furnace body, and high energy consumption. Summary of the Invention

[0004] The purpose of this invention is to provide a composite tank structure for magnesium reduction in a vertical shaft furnace, which is simple to manufacture, has stable performance, long service life, low implementation cost, rapid and uniform heat transfer, low radiative heat loss, ensures product quality and production capacity, and has low operation and maintenance costs.

[0005] The present invention discloses a composite tank structure for magnesium reduction in a vertical shaft furnace, comprising a composite tank body, a bell valve and a crystallizer located at the lower part of the composite tank body, the composite tank body comprising an outer tank, an inner tank, distribution stiffeners, a constricting section, a support plate, a slag discharge cylinder and a flange, the inner tank being connected to the outer tank via the distribution stiffeners, the inner tank having evenly distributed openings to guide magnesium vapor, the outer tank having a support plate at the bottom, the slag discharge cylinder and flange being connected to the outer tank below the support plate; the inner wall of the bottom of the outer tank is connected to an inclined constricting section, the bottom of the constricting section being connected to the slag discharge cylinder.

[0006] The composite tank is provided with an inner cover on top and a middle cover on the top of the composite tank. The outer cover is connected to the composite tank through a first heat insulation block.

[0007] The outer cover is equipped with a dust cover.

[0008] The bell valve includes a valve seat with a small stiffener inside. The bottom of the pull rod is connected to the middle of the stiffener via a sleeve and a nut, and a lifting ring is connected to the top of the pull rod.

[0009] The crystallizer includes a crystallization cylinder, a material shielding cover above the crystallization cylinder, a material shielding pipe below the crystallization cylinder, a vacuum suction port inside the material shielding pipe, and a steam baffle plate on the outer wall of the crystallization cylinder.

[0010] The crystallizer is provided with a water-cooled lower cover, which includes a water-cooling jacket. The water-cooling jacket has a double cylindrical structure. The upper part of the water-cooling jacket is sealed with a circular plate, and the lower part is connected to the lower cover flange. A vacuum port is provided in the middle of the lower cover flange. Through holes are provided on the circumference of the lower cover flange. The through holes are connected to the water inlet pipe and the water outlet pipe respectively. A support base is provided at the bottom of the lower cover flange.

[0011] A second heat insulation block is installed between the water-cooled jacket and the steam baffle of the crystallizer.

[0012] A third heat insulation block is provided between the slag discharge cylinder and the bottom furnace lining of the composite tank.

[0013] A slag discharge hammer is provided between the outer and inner tanks of the composite tank.

[0014] The composite tank is a cast steel welded structure, with the outer tank and inner tank welded together by distributed stiffeners.

[0015] Beneficial Effects: This invention provides a composite tank structure for a vertical shaft magnesium reduction furnace. The composite tank is welded from heat-resistant cast steel and reinforced with distributed stiffeners, making it resistant to deformation and with a long service life. Furthermore, the design of the inner and outer tank structures, as well as the multiple lids and heat insulation blocks, effectively prevents heat loss. The bell valve, water-cooled lower cover, and other components have a reasonable structural design, are easy to install, and have low manufacturing costs. Compared with existing technologies, the structure of this invention is simple to manufacture, has stable performance, a long service life, lower implementation costs, rapid and uniform heat transfer, less radiative heat loss, ensures product quality and production capacity, and has low operating and maintenance costs. Attached Figure Description

[0016] Figure 1 This is a schematic elevation view of the present invention;

[0017] Figure 2 This is a schematic elevation view of the composite tank component of the present invention;

[0018] Figure 3 This is a top view of the composite tank component of the present invention;

[0019] Figure 4 This is a schematic diagram of the bell valve component of the present invention;

[0020] Figure 5 This is a schematic diagram of the crystallizer components of the present invention;

[0021] Figure 6 This is a schematic diagram of the water-cooled lower cover component of the present invention.

[0022] Figure reference numerals: 1. Dust cover; 2. Outer cover; 3. Middle cover; 4. Inner cover; 5. Composite tank; 6. Bell valve; 7. Crystallizer; 8. Water-cooled lower cover; 91. First heat insulation block; 92. Second heat insulation block; 93. Third heat insulation block; 10. Slag discharge hammer; 51. Outer tank; 52. Inner tank; 53. Distribution stiffener; 54. Closing section; 55. Support plate; 56. Slag discharge cylinder; 57. Flange; 61. Valve seat; 62. Small stiffener; 63. Sleeve; 64. Nut; 65. Tie rod; 66. Lifting ring; 71. Material shield; 72. Steam baffle; 73. Crystallizer cylinder; 74. Material protection pipe; 81. Water-cooled jacket; 82. Lower cover flange; 83. Water inlet pipe; 84. Water outlet pipe; 85. Support seat; 86. Vacuum port. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] Embodiment 1 of the present invention.

[0025] A composite tank structure for magnesium reduction in a vertical shaft furnace includes a composite tank 5. A bell valve 6 and a crystallizer 7 are provided at the lower part of the composite tank 5. The composite tank 5 includes an outer tank 51, an inner tank 52, a distribution stiffener 53, a constriction section 54, a support plate 55, a slag discharge cylinder 56, and a flange 57. The inner tank 52 is connected to the outer tank 51 through the distribution stiffener 53. The inner tank 52 has evenly distributed openings to guide magnesium vapor. The bottom of the outer tank 51 is provided with a support plate 55. The slag discharge cylinder 56 and the flange 57 are connected to the outer tank 51 below the support plate 55. The inner wall of the bottom of the outer tank 51 is connected to an inclined constriction section 54. The bottom of the constriction section 54 is connected to the slag discharge cylinder 56.

[0026] The inner tank 52 can evenly distribute materials, the support plate 55 bears the entire weight of the composite tank 5, the flange 57 is machined with annular socket sealing grooves, and has embedded vacuum rubber, which together with the water-cooled lower cover 8 forms the lower sealing structure of the vacuum inside the tank; the magnesium vapor reduced at high temperature enters through the evenly distributed openings of the inner tank 52 and flows downward.

[0027] Example 2.

[0028] Furthermore, an inner cover 4 is provided on the top of the composite tank 5, and a middle cover 3 is provided on the top of the composite tank 5. The outer cover 2 is connected to the composite tank 5 by a first heat insulation block 91. The outer cover 2 is placed inside the dust cover 1 and is welded from a cylindrical outer shell and a top plate. It is used to shield the radiant heat from the vertical tank direction. The first heat insulation block 91 below the outer cover 2 can prevent the flue gas from leaking out of the gap between the vertical tank and the furnace. The middle cover 3 is a circular plate structure made of heat-resistant steel, with ribs reinforcing the upper part and an annular socket-type sealing groove around the perimeter. An expanded graphite gasket is embedded inside. The middle cover 3 is pressed tightly and sealed with the upper cylindrical body of the composite tank 5. It is the main upper sealing structure for achieving vacuum inside the tank and can also shield the radiant heat from the vertical tank direction.

[0029] The inner cover 4 is a circular plate structure made of heat-resistant steel, reinforced with stiffeners at the top and insulated with fire-resistant fiber at the bottom. It is placed on the support platform inside the composite tank 5 and is the main structure for achieving heat preservation of the upper part of the tank, as well as the upper auxiliary sealing structure for achieving vacuum inside the tank.

[0030] The outer cover 2 is equipped with a dust cover 1. The dust cover 1 is a cylindrical structure with openings at the top and bottom, including a cylindrical body and a bottom plate, covering the entire perimeter of the vertical tank; the dust cover 1 is supported on the furnace surface, and a smoke and dust suction port is provided on one side, which is connected to the dust removal facility after several vertical tanks are collected; the dust cover 1 also serves as a protective railing for operators when loading and discharging slag.

[0031] The bell valve 6 includes a valve seat 61, inside which is a small reinforcing plate 62. The bottom of the pull rod 65 is connected to the middle of the small reinforcing plate 62 through a sleeve 63 and a nut 64. The top of the pull rod 65 is connected to a lifting ring 66. When the bell valve 6 is lowered during feeding, the valve seat 61 is in close contact with the constricted section 54 of the composite tank to achieve the material storage function; when the bell valve 6 is raised during slag discharge, the slag particles automatically slide down and are discharged.

[0032] The crystallizer 7 includes a crystallization cylinder 73, a material shielding cover 71 above the crystallization cylinder 73, a material shielding pipe 74 below the crystallization cylinder 73, a vacuum suction port inside the material shielding pipe 74, and a steam baffle plate 72 on the outer wall of the crystallization cylinder 73.

[0033] The material cover 71 is placed above the crystallization cylinder 73 to prevent sporadic material from falling. The crystallization cylinder 73 is used for magnesium vapor crystallization. Magnesium vapor flows down from the inner tank 52 through the gap between the small ribs 62 of the bell valve, flows around the material cover 71 to the periphery of the crystallization cylinder 73, and then enters the crystallization cylinder 73 through the groove in the cylinder wall for condensation.

[0034] The crystallizer 7 is provided with a water-cooled lower cover 8 below it. The water-cooled lower cover 8 includes a water-cooling sleeve 81, which is a double cylindrical structure. The upper part of the water-cooling sleeve 81 is sealed with a circular plate, and the lower part is connected to the lower cover flange 82. A vacuum port 86 is provided in the middle of the lower cover flange 82. Through holes are provided on the circumference of the lower cover flange 82, and the through holes are respectively connected to the water inlet pipe 83 and the water outlet pipe 84. A support seat 85 is provided at the bottom of the lower cover flange 82.

[0035] The lower cover flange 82 is welded as the base; the water-cooled jacket 81 is used to cool magnesium vapor; the space in the center of the water-cooled jacket 81 is used to place the crystallizer 7, and the vacuum pipe port 86 is welded to the center of the lower cover and inserted into the crystallizer 7; the support base 85 is used to lift the entire water-cooled lower cover 8, and the lower cover flange 82 has several quick clips around its periphery that connect to the flange 57 of the composite tank 5.

[0036] A second heat insulation block 92 is provided above the water-cooled jacket 81 and between it and the steam baffle plate 72 of the crystallizer 7.

[0037] A third heat insulation block 93 is provided between the slag discharge cylinder 56 of the composite tank 5 and the bottom furnace lining.

[0038] A slag discharge hammer 10 is provided between the outer tank 51 and the inner tank 52 of the composite tank body 5. It is used during loading and slag discharge: it assists in slag discharge by impacting the coking slag pile, and reduces breakage by guiding the material ball during loading.

[0039] The composite tank 5 is a cast steel welded structure, and the outer tank 51 and the inner tank 52 are welded together by distributed stiffeners 53.

[0040] During the feeding operation, first, put the empty crystallizer 7 with the first heat insulation block 91, and put them into the water-cooled lower cover 8. Connect the vacuum hose and the cooling water inlet and outlet hose, and push the water-cooled lower cover 8 into the composite tank 5 from below, and put on the quick buckle; then lower the bell valve 6, and add the reactants into the inner and outer tank jacket of the composite tank 5. During this process, use the slag discharge hammer 10 to assist in the feeding; then seal the inner cover 4, middle cover 3, and outer cover 2 in sequence, turn on the cooling water, turn on the vacuum pump, and start magnesium reduction and magnesium vapor crystallization until the end.

[0041] During the slag discharge operation, the vacuum pump is turned off and the vacuum inside the tank is released. The quick-release buckle is removed, and the water-cooled lower cover 8 and other components are detached, lowered, and removed. The magnesium ingots in the crystallizer 7 can be easily removed. Then, the slag container is moved in and aligned with the slag discharge cylinder 56 of the composite tank 5. The outer cover 2, middle cover 3, and inner cover 4 are removed in sequence. The bell valve 6 is lifted and slag discharge begins. During this process, the slag discharge hammer 10 is used to assist in cleaning. After the slag discharge is completed, the slag container is removed and the next cycle begins.

[0042] In addition to the preferred embodiments described above, the present invention has other embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection claimed by the present invention.

Claims

1. A composite tank structure for magnesium reduction in a vertical shaft furnace, comprising a composite tank (5), characterized in that: The composite tank (5) is equipped with a bell valve (6) and a crystallizer (7) at the bottom. The composite tank (5) includes an outer tank (51), an inner tank (52), a distribution rib plate (53), a constriction section (54), a support plate (55), a slag discharge cylinder (56), and a flange (57). The outer tank (51) is connected to the inner tank (52) through the distribution rib plate (53). The inner tank (52) has evenly distributed openings to guide magnesium vapor. The bottom of the outer tank (51) is equipped with a support plate (55). The outer tank (51) is connected to the slag discharge cylinder (56) and the flange (57) below the support plate (55). The inner wall of the bottom of the outer tank (51) is connected to the inclined constriction section (54). The bottom of the constriction section (54) is connected to the slag discharge cylinder (56).

2. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: The composite tank (5) is provided with an inner cover (4) on top and a middle cover (3) on the top of the composite tank (5). The outer cover (2) is connected to the composite tank (5) by a first heat insulation block (91).

3. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 2, characterized in that: The outer cover (2) is provided with a dust cover (1).

4. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: The bell valve (6) includes a valve seat (61), a small stiffener (62) is provided inside the valve seat (61), the bottom of the pull rod (65) is connected in the middle of the small stiffener (62) through a sleeve (63) and a nut (64), and the top of the pull rod (65) is connected to a lifting ring (66).

5. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: The crystallizer (7) includes a crystallization cylinder (73), a material shielding cover (71) is provided above the crystallization cylinder (73), a material shielding pipe (74) is provided below the crystallization cylinder (73), a vacuum suction pipe is provided inside the material shielding pipe (74), and a steam baffle plate (72) is provided on the outer wall of the crystallization cylinder (73).

6. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: The crystallizer (7) is provided with a water-cooled lower cover (8) below it. The water-cooled lower cover (8) includes a water-cooled sleeve (81). The water-cooled sleeve (81) has a double cylindrical structure. The upper part of the water-cooled sleeve (81) is sealed with a circular plate, and the lower part is connected to the lower cover flange (82). A vacuum port (86) is provided in the middle of the lower cover flange (82). A through hole is provided on the circumference of the lower cover flange (82). The through hole is connected to the water inlet pipe (83) and the water outlet pipe (84) respectively. A support seat (85) is provided at the bottom of the lower cover flange (82).

7. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 6, characterized in that: A second heat insulation block (92) is provided above the water cooling jacket (81) and between the steam baffle plate (72) of the crystallizer (7).

8. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: A third heat insulation block (93) is provided between the slag discharge cylinder (56) of the composite tank (5) and the bottom furnace lining.

9. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: A slag discharge hammer (10) is provided between the outer tank (51) and the inner tank (52) of the composite tank (5).

10. The composite tank structure for a vertical shaft magnesium reduction furnace according to claim 1, characterized in that: The composite tank (5) is a cast steel welded structure, and the outer tank (51) and the inner tank (52) are welded together by distributed stiffeners (53).

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