A large single-chamber magnesium metal vertical tank reduction furnace

Abstract

The present invention relates to the technical field of reduction furnaces for producing magnesium metal, and in particular to a large single-chamber magnesium metal vertical tank reduction furnace, wherein a furnace chamber is provided with a plurality of vertical tanks, and a plurality of rows of arches are provided on the top of the furnace chamber along the length direction of the furnace chamber. In a closed state, a plurality of vertical tanks are arranged in a matrix, and a row of vertical tanks corresponds to a row of vertical tanks under each row of arches; in a closed state, heat storage chambers are provided on the two side walls along the length direction of the furnace chamber, and partition walls are provided between adjacent rows of vertical tanks and on the side of the heat storage chambers facing the furnace chamber, and in a closed state, the partition walls are provided with fire holes, one end of the heat storage chamber is connected to the furnace chamber through an air port, and the other end is connected to the outside of the furnace, and the two heat storage chambers are alternately in a heat release state and a heat storage state, and in a closed state, a plurality of rows of burners are provided on the two end walls along the width direction of the furnace chamber, and each row of burners corresponds to the position of each row of vertical tanks. By arranging heat storage chambers on the side walls, burners on the end walls, and partition walls with fire holes, a large single-chamber vertical tank reduction furnace is formed, which reduces energy consumption while increasing production.

Description

Technical Field

[0001] The invention relates to the technical field of reduction furnaces for producing magnesium metal, and in particular to a large single-chamber type magnesium metal vertical tank reduction furnace. Background Art

[0002] In industry, magnesium smelting technology mainly refers to thermal reduction methods represented by the Pidgeon process. The traditional Pidgeon process uses a horizontal tank reduction furnace, but the automation and continuity of horizontal tank production are extremely poor, and the production capacity is low. In addition, due to the large span of the horizontal tank, the tank body is prone to sinking, bending and deformation in a high temperature environment, shortening the service life of the tank body. In view of this, in recent years, vertical tank reduction furnaces have begun to be used in production to solve the above-mentioned problems with horizontal tanks.

[0003] The vertical tank reduction furnace has a structure where the reduction tank is placed vertically inside the furnace, and a center tube is set inside the vertical tank. During production, the overhead crane is first used to add the pellets to the area between the tank body and the center tube, and then the crystallizer and lid are installed in sequence, so that the pellets are reduced at a temperature of 1200°C. When the reaction is completed, the furnace cover is opened, and the crystallizer is first removed by the overhead crane, and then the center tube is lifted out by the overhead crane. At the same time, a material collecting trolley is used at the bottom of the furnace to collect the slag flowing out from the bottom of the vertical tank. After the slag is removed, the center tube and pellets are put in again for a cyclic operation. The vertical tank reduction furnace eliminates the manual slagging operation, which greatly improves the continuity of the magnesium reduction furnace, and the size of the vertical tank continues to increase, and the production capacity of the magnesium reduction furnace continues to increase. However, there are also some technical difficulties in the production of the vertical tank reduction furnace.

[0004] Figure 1-Figure 3 The cross-sectional view of the structure of the existing vertical drum reduction furnace is shown. A single reduction furnace is composed of multiple existing furnace chambers. Different existing furnace chambers are separated by existing partition walls. The top of each existing furnace chamber is an existing arch. In order to ensure the service strength of the existing arch, the arch span should not be too large, which makes each existing furnace chamber consist of at most two rows of vertical drums. In addition, since the pellet materials often stick together during production, the center tube cannot be pulled out for slag discharge. At this time, the vertical drum needs to be pulled out and a new vertical drum needs to be installed to carry out production. The frequent disassembly and assembly of the vertical drums in the longitudinal direction seriously reduces the service life of the existing arch. It is necessary to minimize the number of vertical drum columns corresponding to a single arch, thereby limiting the production capacity of the vertical drum reduction furnace.

[0005] At the same time, existing heat storage chambers are set on the end walls on both sides of each existing furnace chamber of the existing vertical drum reduction furnace. However, due to the size limitation of the existing furnace chamber and the end wall, the existing heat storage chambers are very small and the number is small, resulting in limited heat storage capacity. The flue gas outlet temperature is as high as 300-500℃ or even higher, causing serious heat storage losses. In addition, due to the capacity limitation of the existing heat storage chambers, there are currently a maximum of 8 vertical drums in a single row and a maximum of 16 vertical drums in a single existing furnace chamber. During the reduction process, the high-temperature flue gas flows from the existing heat storage chamber on one end wall to the existing heat storage chamber on the other end wall. The flow route is simple, and there are flue gas vortices and low-temperature zones, resulting in large temperature differences inside the furnace chamber, which makes the reduction efficiency of some materials inside the vertical drums worse, which not only reduces production capacity but also increases energy consumption.

[0006] Therefore, how to effectively recover the waste heat from flue gas, reduce energy consumption per ton of product, and at the same time break through the limitations of the heat storage chamber, increase the number of vertical tanks as much as possible, and realize the large-scale furnace body, is an important technical problem in the production of magnesium metal vertical tank reduction furnaces. Summary of the invention

[0007] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a large single-chamber magnesium metal vertical tank reduction furnace, which is formed by arranging a heat storage chamber on the side wall, arranging a burner on the end wall, and providing a partition wall with a fire hole, thereby increasing the output while reducing energy consumption.

[0008] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0009] A large single-chamber magnesium metal vertical tank reduction furnace comprises a furnace chamber, wherein a plurality of vertical tanks are arranged, and a plurality of rows of arches are arranged on the top of the furnace chamber along the length direction of the furnace chamber, wherein the plurality of vertical tanks are arranged in a matrix, and a row of vertical tanks corresponds to a row of arches below each row of vertical tanks;

[0010] The two side walls of the furnace chamber along the length direction are respectively provided with heat storage chambers, and partition walls are provided between adjacent rows of vertical tanks and on the side of the heat storage chamber facing the furnace chamber, and the partition wall is provided with fire holes. One end of the heat storage chamber is connected with the furnace chamber through an air port, and the other end is connected with the outside of the furnace. The two heat storage chambers are alternately in a heat release state and a heat storage state. The two end walls of the furnace chamber along the width direction are provided with a plurality of rows of burners, and each row of burners corresponds to the position of each row of vertical tanks.

[0011] By setting up a heat storage chamber on the side wall, the heat storage chamber has a larger installation space, and a heat storage chamber with stronger heat storage capacity can be set up to effectively recover the waste heat of high-temperature flue gas, reducing the heat storage loss of the heat storage chamber. The stored heat can be used for reduction production when switching to the heat release state, reducing energy consumption;

[0012] A single-chamber reduction furnace is formed by arranging burners on the end walls corresponding to the positions of each row of vertical tanks, and by providing a partition wall with fire holes. Multiple rows of burners in the furnace chamber realize multi-stage heating, thereby improving the heating capacity of the reduction furnace. Thus, more than 8 vertical tanks can be arranged in a single row while ensuring the reduction efficiency, breaking through the limitation on the number of vertical tanks in a single row, realizing the large-scale reduction furnace of the vertical tank, improving the production capacity of the vertical tank reduction furnace and reducing energy consumption.

[0013] Furthermore, the fire holes of adjacent partition walls are alternately arranged at the front end or rear end of the partition walls along the width direction of the furnace chamber, and the fire holes of the partition walls at the regenerator are connected to the air ports of the regenerator.

[0014] By alternately setting the positions of the fire holes, the high-temperature flue gas injected into the heat storage chamber flows in a serpentine shape in the furnace chamber, reducing the temperature difference between different parts of the furnace chamber, heating the vertical tank more evenly, and improving the reduction efficiency.

[0015] Furthermore, both ends of the furnace chamber along the width direction are turning fire zones, the width of the turning fire zones is equal to the width of the fire holes, and the matrix-arranged vertical tanks are disposed in the central area of ​​the furnace chamber between the turning fire zones at both ends.

[0016] By placing the vertical tank in the center of the furnace chamber, the problem of uneven heating of the outermost vertical tank in the width direction of the furnace chamber due to eddy currents of high-temperature flue gas at the corners is avoided, thereby improving the reduction efficiency and product quality.

[0017] Furthermore, when the vertical tank has an odd number of rows, the gas outlets of the two heat storage chambers are respectively located at the front end and the rear end of the furnace chamber; when the vertical tank has an even number of rows, the gas outlets of the two heat storage chambers are simultaneously located at the front end or the rear end of the furnace chamber.

[0018] Furthermore, in the heat release state, the burner at the gas outlet of the heat storage chamber is in a working state, only the burner corresponding to one end of each row of vertical tanks is in a working state, and the burners in adjacent rows are alternately in a working state or a closed state.

[0019] By alternately operating the burners in adjacent rows, the direction of the gas ejected from the burners is made consistent with the direction of the high-temperature flue gas, thereby improving the reduction efficiency.

[0020] Furthermore, a thermocouple is provided at the center of each row of burners, and the thermocouple is connected to the furnace chamber.

[0021] By setting a thermocouple, the air jet volume of the burner can be fed back in real time according to the temperature measurement data of the thermocouple, which is helpful for temperature monitoring of large-scale reduction furnaces and ensuring product quality.

[0022] Furthermore, a steel smoke hood is provided at one end of the heat storage chamber that is connected to the outside of the furnace.

[0023] A steel smoke hood is provided to realize the input of cold air or the output of smoke, thereby achieving periodic heat storage and release.

[0024] Furthermore, the heat storage chamber is provided with an inlet valve for switching the heat storage chamber between a heat release state and a heat storage state.

[0025] The beneficial effects of the present invention are:

[0026] A large-scale single-chamber magnesium metal vertical tank reduction furnace of the present invention has large-volume heat storage chambers symmetrically arranged inside the side walls on both sides, which can effectively recover the waste heat of high-temperature flue gas, and each row of vertical tanks is separated into a heating area by a partition wall. The heating areas are connected through fire holes to construct a single-chamber multi-stage heating reduction furnace. By arranging burners and thermocouples at both ends of each heating area in the furnace, the amount of fuel gas sprayed into the burner is controlled by the feedback temperature of the thermocouple, so that the temperature inside the furnace can be effectively controlled.

[0027] Under the premise of ensuring the reduction efficiency, the present invention can set more than 8 vertical tanks in a single row, breaking through the limitation of the number of vertical tanks in a single row, realizing the large-scale vertical tank reduction furnace, improving the production capacity of the vertical tank reduction furnace, and effectively recovering the waste heat of high-temperature flue gas to reduce investment in production, reduce heat dissipation losses, and comprehensively reduce energy consumption per ton of product. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the current vertical tank magnesium reduction furnace;

[0029] Figure 2 for Figure 1 Schematic cross-section at AA;

[0030] Figure 3 for Figure 2 Schematic cross-section at BB;

[0031] Figure 4 It is a structural schematic diagram of a large single-chamber magnesium metal vertical tank reduction furnace of the present invention;

[0032] Figure 5 for Figure 4 Schematic cross-section at CC;

[0033] Figure 6 for Figure 5 Schematic cross section at DD.

[0034] In the figure: 1. furnace chamber; 2. vault; 3. side wall; 4. end wall; 5. vertical tank; 6. heat storage chamber; 7. air inlet; 8. burner; 9. partition wall; 10. fire hole; 11. thermocouple; 12. steel smoke hood; 13. steel column; 14. current furnace chamber; 15. current heat storage chamber; 16. current partition wall; 17. current vault. DETAILED DESCRIPTION

[0035] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below in conjunction with the accompanying drawings through specific embodiments. Figure 4 Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0036] Figure 4-Figure 6 A large single-chamber magnesium vertical tank 5 reduction furnace is shown, comprising a furnace chamber 1, wherein the furnace chamber 1 is provided with a plurality of vertical tanks 5, wherein the top of the furnace chamber 1 is provided with a plurality of rows of arches 2 along the length direction of the furnace chamber 1, wherein the plurality of vertical tanks 5 are arranged in a matrix, and a row of vertical tanks 5 corresponds to a row of arches 2 below each row of vertical tanks 5;

[0037] The two side walls 3 of the furnace chamber 1 along the length direction are respectively provided with heat storage chambers 6, and partition walls 9 are provided between adjacent rows of vertical tanks 5 and on the side of the heat storage chambers 6 facing the furnace chamber 1, and the partition wall 9 is provided with fire holes 10. One end of the heat storage chamber 6 is connected with the furnace chamber 1 through the air port 7, and the other end is connected with the outside of the furnace. The two heat storage chambers 6 are alternately in a heat release state and a heat storage state. The two end walls 4 of the furnace chamber 1 along the width direction are both provided with a plurality of rows of burners 8, and each row of burners 8 corresponds to the position of each row of vertical tanks 5.

[0038] By arranging the heat storage chamber 6 on the side wall 3, the heat storage chamber 6 has a larger installation space, and the heat storage chamber 6 with stronger heat storage capacity can be arranged, and the flue gas outlet temperature can be reduced to a lower temperature within 50°C, so that the flue gas waste heat can be recovered to the maximum extent possible, and the heat storage loss of the heat storage chamber 6 is reduced. The stored heat can be used for reduction production when switching to the heat release state, thereby reducing energy consumption;

[0039] A single-chamber reduction furnace is formed by arranging burners 8 on the end wall 4 corresponding to the positions of each row of vertical tanks 5, and a partition wall 9 with fire holes 10. Multiple rows of burners 8 in the furnace chamber 1 realize multi-stage heating, thereby improving the heating capacity of the reduction furnace. Thus, more than 8 vertical tanks 5 can be arranged in a single row while ensuring the reduction efficiency, breaking through the limitation on the number of vertical tanks 5 in a single row, realizing the large-scale reduction furnace of the vertical tank 5, improving the production capacity of the reduction furnace of the vertical tank 5 and reducing energy consumption.

[0040] Specifically, the fire holes 10 of adjacent partition walls 9 are alternately arranged at the front end or rear end of the partition walls 9 along the width direction of the furnace chamber 1 , and the fire holes 10 of the partition walls 9 at the regenerator 6 are connected to the air port 7 of the regenerator 6 .

[0041] By alternately arranging the positions of the fire holes 10, the high-temperature flue gas injected into the heat storage chamber 6 flows in a serpentine shape in the furnace chamber 1, thereby reducing the temperature difference between various parts of the furnace chamber 1, heating the vertical tank 5 more evenly, and improving the reduction efficiency.

[0042] Specifically, the two ends of the furnace chamber 1 along the width direction are turning fire zones, the width of the turning fire zones is equal to the width of the fire holes 10, and the matrix-arranged vertical tanks 5 are disposed in the central area of ​​the furnace chamber 1 between the turning fire zones at both ends.

[0043] By arranging the vertical tank 5 at the center of the furnace chamber 1, the problem of uneven heating of the outermost vertical tank 5 in the width direction of the furnace chamber 1 due to eddy currents of high-temperature flue gas at the corners is avoided, thereby improving the reduction efficiency and product quality.

[0044] Specifically, when the vertical tank 5 has an odd number of rows, the air inlets 7 of the two heat storage chambers 6 are respectively located at the front end and the rear end of the furnace chamber 1; when the vertical tank 5 has an even number of rows, the air inlets 7 of the two heat storage chambers 6 are simultaneously located at the front end or the rear end of the furnace chamber 1.

[0045] Specifically, in the heat release state, the burner 8 at the gas port 7 of the heat storage chamber 6 is in working state, only the burner 8 corresponding to one end of each row of vertical tanks 5 is in working state, and the burners 8 in adjacent rows are alternately in working state or closed state.

[0046] By alternately operating the burners 8 in adjacent rows, the direction of the fuel gas ejected from the burners 8 is made consistent with the direction of the high-temperature flue gas, thereby improving the reduction efficiency.

[0047] Specifically, a thermocouple 11 is provided at the center of each row of burners 8 , and the thermocouple 11 is connected to the furnace chamber 1 .

[0048] By providing the thermocouple 11, the gas injection amount of the burner 8 can be fed back in real time according to the temperature measurement data of the thermocouple 11, which is helpful for temperature monitoring of a large-scale reduction furnace and ensuring product quality.

[0049] Specifically, a steel smoke hood 12 is provided at one end of the heat storage chamber 6 that is connected to the outside of the furnace.

[0050] The steel smoke hood 12 is provided to realize the input of cold air or the output of smoke, thereby realizing periodic heat storage and release.

[0051] Specifically, the heat storage chamber 6 is provided with an inlet valve for switching the heat storage chamber 6 between a heat release state and a heat storage state.

[0052] The working process of a large single-chamber magnesium vertical tank reduction furnace of the present invention is as follows:

[0053] Cold air is introduced into the regenerator 6 on one side of the reduction furnace from the steel smoke hood 12, and the regenerator 6 preheats the cold air to high-temperature air, and the high-temperature air enters the furnace chamber 1 through the gas port 7 of the regenerator 6 and the fire hole 10 of the partition wall 9 at the regenerator 6. At this time, the burner 8 column closest to the gas port 7 of the regenerator 6 is in a working state, and the high-temperature air is mixed with the gas injected by the burner 8 and then burned. At this time, the burner 8 column at the gas port 7 opposite to the burner 8 column along the width direction of the furnace chamber 1 is in a closed state, and the burners 8 of adjacent columns are alternately in a working state or a closed state, and the high-temperature flue gas flows in the furnace chamber 1 along a serpentine through the fire hole 10 of the partition wall 9, and the thermocouple 11 measures the temperature data to adjust the gas injection amount of the burner 8 in each heating area; the high-temperature flue gas flows into the regenerator 6 on the other side of the reduction furnace after passing through the vertical tank 5 area, and the low-temperature flue gas is discharged after heat storage in the regenerator 6.

[0054] After the heat storage chamber 6 is full of heat, the inlet valve of the heat storage chamber 6 is switched, the burner 8 in the working state is switched to the closed state, and the burner 8 in the closed state is switched to the working state, so that the cold air is heated by the heat storage chamber 6 full of heat and then enters the furnace, and the high-temperature flue gas in the furnace chamber 1 flows in the opposite direction, starting a new round of heat storage production.

[0055] As a comparison, Figure 1-Figure 3 The structural cross-section of the existing vertical tank reduction furnace is shown. A single reduction furnace is composed of multiple existing furnace chambers 14. Different existing furnace chambers 14 are separated by existing partition walls 16. The top of each existing furnace chamber 14 is an existing vault 17. Each existing furnace chamber 14 is composed of two rows of vertical tanks 5. At the same time, existing heat storage chambers 15 are arranged on the end walls 4 on both sides of each existing furnace chamber 14 of the existing vertical tank reduction furnace. However, due to the size limitation of the existing furnace chamber 14 and the end wall 4, the existing heat storage chambers 15 are very small and the number is also small, resulting in limited heat storage capacity. The flue gas outlet temperature is as high as 300-500℃ or even higher, causing serious heat storage losses. During the reduction process, the high-temperature flue gas flows from the existing heat storage chamber 15 of the end wall 4 on one side to the existing heat storage chamber 15 of the end wall 3 on the other side. The flow route is simple, and there are flue gas vortices and low-temperature areas, resulting in large temperature differences inside the existing furnace chamber 14, which makes the reduction efficiency of the materials inside some vertical tanks 5 worse, which not only reduces the production capacity but also increases the energy consumption.

[0056] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A large single-chamber magnesium metal vertical tank reduction furnace, comprising a furnace chamber (1), wherein the furnace chamber (1) is provided with a plurality of vertical tanks (5), characterized in that: The top of the furnace chamber (1) is provided with a plurality of rows of arches (2) along the length direction of the furnace chamber (1), and the plurality of vertical tanks (5) are arranged in a matrix, with a row of vertical tanks (5) corresponding to each row of arches (2); The two side walls (3) of the furnace chamber (1) along the length direction are respectively provided with heat storage chambers (6), and partition walls (9) are provided between adjacent rows of vertical tanks (5) and on the side of the heat storage chambers (6) facing the furnace chamber (1), and the partition wall (9) is provided with a fire hole (10). One end of the heat storage chamber (6) is connected to the furnace chamber (1) through the air port (7), and the other end is connected to the outside of the furnace. The two heat storage chambers (6) are alternately in a heat release state and a heat storage state. The two end walls (4) of the furnace chamber (1) along the width direction are both provided with a plurality of rows of burners (8), and each row of burners (8) corresponds to the position of each row of vertical tanks (5); The fire holes (10) of adjacent partition walls (9) are alternately arranged at the front end or rear end of the partition walls (9) along the width direction of the furnace chamber (1), and the fire holes (10) of the partition walls (9) at the heat storage chamber (6) are connected to the air port (7) of the heat storage chamber (6); The two ends of the furnace chamber (1) along the width direction are turning and firing zones, the width of which is equal to the width of the firing hole (10), and the vertical tanks (5) arranged in a matrix are arranged in the central area of ​​the furnace chamber (1) between the turning and firing zones at the two ends.

2. A large single-chamber magnesium vertical reduction furnace as claimed in claim 1, characterized in that: When the vertical tank (5) has an odd number of rows, the gas outlets (7) of the two heat storage chambers (6) are respectively located at the front end and the rear end of the furnace chamber (1); when the vertical tank (5) has an even number of rows, the gas outlets (7) of the two heat storage chambers (6) are simultaneously located at the front end or the rear end of the furnace chamber (1).

3. A large single-chamber magnesium vertical reduction furnace as claimed in claim 1, characterized in that: In the heat release state, the burner (8) at the air port (7) of the heat storage chamber (6) is in an operating state. Only the burner (8) corresponding to one end of each row of vertical tanks (5) is in an operating state, and the burners (8) in adjacent rows are alternately in an operating state or a closed state.

4. A large single-chamber magnesium vertical reduction furnace as claimed in claim 3, characterized in that: A thermocouple (11) is provided at the center of each row of burners (8), and the thermocouple (11) is connected to the furnace chamber (1).

5. A large single-chamber magnesium vertical reduction furnace as claimed in claim 1, characterized in that: A steel smoke hood (12) is provided at one end of the heat storage chamber (6) that is in communication with the outside of the furnace.

6. A large single-chamber magnesium vertical reduction furnace as claimed in claim 1, characterized in that: The heat storage chamber (6) is provided with an inlet valve for switching the heat storage chamber (6) between a heat release state and a heat storage state.

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