A method for installing, adjusting and positioning a vertical cathode furnace on site for an oxygen-aluminum co-production electrolytic cell

Abstract

The present invention belongs to the field of aluminum smelting, and discloses a method for on-site installation, adjustment and positioning of a vertical cathode furnace for an oxygen-aluminum co-production electrolytic cell. The method is mainly divided into two parts. The first part is the adjustment and positioning of the cathode steel bar, which is specifically: a method of vertically positioning the end or middle part of the steel bar by a toothed tool, a method of horizontal positioning by an anti-displacement object, or a method of positioning by welding the steel bars in series, or a method of using four methods at the same time, to prevent the cathode steel bar from horizontal or vertical displacement; the second part is the installation and positioning of the cathode plate, which adopts a C-type positioning bar method, and fixes the conductive piles of adjacent cathode steel bars by the C-type positioning bar to limit their displacement; the present invention is mainly a construction method used to ensure the pole distance of the cathode steel bar and the cathode plate before the installation of the oxygen-aluminum co-production electrolytic cell, which can prevent the pole distance from changing; at the same time, all the tools mentioned in the present invention must be removed after the construction is completed, and they are only a tool to ensure the construction accuracy before construction, and no additional materials will be added, saving costs.

Description

Technical Field

[0001] The invention belongs to the field of aluminum smelting, and in particular relates to a method for on-site installation, adjustment and positioning of a vertical cathode furnace for an oxygen-aluminum co-production electrolytic cell. Background Art

[0002] The current Hall-Herout aluminum electrolytic cells use consumable carbon anodes, which not only consume a large amount of carbon materials, mainly high-quality petroleum coke, and emit a large amount of greenhouse gas CO2, strong greenhouse gas fluorocarbons (CF4, C2F6), and SO2, but also in the current aluminum electrolysis process, the pre-baked anode carbon blocks need to be constantly replaced, resulting in unstable electrolytic production, increased labor intensity, personal risks for workers facing high-temperature melts, and unorganized emissions of fluorides; the production process of pre-baked carbon anodes also emits carcinogenic aromatic compounds (PAH), SO2, and dust, which are one of the main sources of PM2.5; in addition, the use of carbon anodes is also one of the main reasons for the high energy consumption and high cost of the current aluminum electrolysis process.

[0003] The use of non-carbon anodes or inert anodes to achieve a new process of oxygen and aluminum co-production electrolysis can solve the above-mentioned emission and pollution problems, and can improve production efficiency, reduce floor space, and reduce production costs, and has become the focus of attention and research hotspot in the international aluminum industry and materials industry. The use of non-carbon anodes in the oxygen-aluminum co-production electrolysis process has the following advantages: (1) The electrodes are almost not consumed during the electrolysis process, and the material consumption is less than one percent of that of carbon anodes. There is no need for an affiliated carbon processing plant and carbon anode assembly plant, which reduces production costs and eliminates the environmental impact and pollution caused by the production and use of carbon anodes; (2) The electrodes are not consumed, the electrode distance is stable and easy to control, the frequency of anode replacement is reduced by more than ten times, and the labor intensity and occupational risks are greatly reduced; (3) A higher unit volume current can be used to increase the production capacity of the electrolytic cell; (4) The product of the anode is oxygen, which avoids environmental pollution, and oxygen can also be used as a by-product.

[0004] Using non-carbon anodes changes the aluminum electrolysis reaction equation from

[0005] Al2O3+C=Al+CO2,E=1.2V

[0006] Convert to

[0007] Al2O3=Al+O2,E=2.2V

[0008] The theoretical decomposition voltage of the latter is 1V higher than that of the former. Therefore, the use of non-carbon inert anodes requires a more heat-insulating electrolytic cell structure, and a vertical electrolytic cell is required. The inert anode aluminum electrolytic cell with vertical electrode arrangement can increase the electrode area exponentially, and the size of the inert anode and inert cathode is small, thereby reducing the volume of the electrolytic cell, increasing the yield, and reducing heat dissipation, making up for the disadvantage that the theoretical decomposition voltage of the inert anode is higher than that of the carbon anode.

[0009] However, the vertical inert cathode standing at the bottom of the tank must be required to maintain the same distance as the inert anode during the operation of the electrolytic cell, otherwise it will affect the current distribution, resulting in abnormal operation of the electrolytic cell, local temperature rise, increased corrosion of non-carbon anodes and other adverse consequences. Therefore, it is necessary to adjust and accurately position the cathode large and small steel bars and cathode plates on site when the electrolytic cell is built. In normal production, if there is a deviation in the local distance, the anode current on the corresponding side will be higher than the mean, and the anode current on the other side will be lower than the mean. When it is higher or lower than the mean by 10%, it will cause uneven distribution of anode current, resulting in local overheating, fluctuations in the electrolytic cell voltage, and reduced current efficiency. If the cathode installation error is large during furnace construction, the electrolytic cell will not be able to be adjusted in the later stage of startup. In severe cases, it may cause the electrolytic cell to stop, which directly affects the life of the electrolytic cell.

[0010] Therefore, in order to ensure accurate pole distance, adjustments must be made at the source at the furnace installation site. Summary of the invention

[0011] The purpose of the present invention is to provide a method for on-site installation, adjustment and positioning of a vertical cathode in an oxygen-aluminum co-production electrolytic cell; the oxygen-aluminum co-production electrolytic cell adopts vertically arranged inert anodes and inert cathodes, the inert anodes and inert cathodes are arranged alternately and parallel to each other, and the horizontal distance between the corresponding parts of the cathode and the anode is called the pole distance. The requirements for the pole distance in normal production are very strict, and the pole distance of the same electrolytic cell must be guaranteed to be the same.

[0012] The invention provides a method for on-site installation and adjustment of a vertical cathode furnace for an oxygen-aluminum co-production electrolytic cell, which is mainly divided into two parts: one is the adjustment and positioning of a cathode steel bar, and the other is the installation and positioning of a cathode plate.

[0013] The specific steps are as follows:

[0014] (1) Adjustment and positioning of cathode steel rod

[0015] After the first layer of dry anti-seepage material in the oxygen-aluminum co-production electrolytic cell is vibrated and scraped flat, the cathode steel bars are installed. After all the cathode steel bars are placed, the center reference cathode steel bar is first adjusted and positioned, and then a level ruler is used to adjust and position it horizontally. After the first cathode steel bar is determined, it is used as the center reference and then other cathode steel bars are adjusted and positioned on both sides.

[0016] The cathode steel rod adjustment and positioning refers to ensuring that the two sides of the cathode are parallel and equidistant from the two sides of the anode. The specific method of adjustment and positioning is as follows:

[0017] A. Use a toothed tool to vertically position the end of the steel rod: Use a toothed tool to vertically position the end of the cathode steel rod. Insert the toothed tool vertically into the ends of two or more adjacent groups of cathode steel rods to prevent the cathode steel rods from shifting.

[0018] B. Use toothed tool 2 to vertically locate the middle part of the steel rod: Use toothed tool 2 to vertically locate two or more adjacent groups of cathode steel rods, insert toothed tool 2 into the middle part of two adjacent groups of cathode steel rods to lock them, so as to prevent the displacement of cathode steel rods;

[0019] C. Use anti-displacement object horizontal positioning method: Use anti-displacement objects to prevent horizontal displacement of two adjacent cathode steel bars. The anti-displacement objects are stuck between the two adjacent cathode steel bars to limit the movement of the cathode steel bars, so as to prevent the cathode steel bars from moving horizontally.

[0020] D. Use the steel rod series welding positioning method: After the cathode steel rod is adjusted into place, that is, the cathode steel rod is perpendicular to the bottom of the electrolytic cell and the cathode steel rods are parallel to each other; the cathode steel rod is welded in series at both ends, that is, the cathode steel rod is fixed by welding bars to prevent horizontal or vertical displacement of the cathode steel rod.

[0021] A, B, C or D can be used alone or in combination, in no particular order.

[0022] (2) Installation and positioning of cathode plate

[0023] The C-type positioning bar method is adopted: after the cathode steel bar is adjusted and positioned in step (1), in order to further ensure the installation accuracy of the cathode plate and prevent the displacement of the conductive piles when the second layer of dry anti-seepage material is vibrated, the cathode plate insertion positions of two or more adjacent cathode steel bar conductive piles are positioned using C-type positioning bars; the conductive piles of adjacent cathode steel bars are fixed by the C-type positioning bars to limit their displacement;

[0024] (3) After the implementation of step (1) and step (2), when the second layer of dry anti-seepage material is laid in the oxygen-aluminum co-production electrolytic cell, the cathode steel rod will not be displaced during the vibration process or after being affected by external force, so as to ensure the accuracy of the installation of the cathode steel rod and ensure that the pole distance will not deviate;

[0025] (4) After the second layer of dry anti-seepage material is laid, remove the tools used for positioning and adjusting the cathode steel rod in step (1); including toothed tool 1, toothed tool 2, anti-displacement object and series welding strip; and simultaneously remove the C-shaped positioning strip in step (2);

[0026] (5) Distance measurement method using a rangefinder: After the lining material of the electrolytic cell is completed, the cathode plates are installed. The middle group of cathode plates is selected as the reference plane for installation and positioning on both sides. After positioning, a micro laser rangefinder is used to measure the distance of the same part of an adjacent group of cathode plates using one end of the selected cathode plate as the reference plane, with a tolerance of ±0.15 mm.

[0027] Preferably, the oxygen-aluminum co-production electrolytic cell in step (1) uses vertically arranged inert anodes and inert cathodes, which are arranged alternately, with the vertical anode suspended on the upper part of the electrolytic cell and the vertical cathode placed on the bottom substrate of the electrolytic cell.

[0028] Preferably, the adjustment and positioning of the center reference cathode steel bar in step (1) is performed by using a visual system to determine the installation status of the cathode steel bar; the visual system is specifically an automatic detection system for the anode and cathode postures, including an anode template, a laser rangefinder, an industrial control computer and a software system.

[0029] Preferably, the shape of the anti-displacement object in step (1) is not limited, and it can be stuck between two adjacent cathode steel bars; the anti-displacement object can also be a device with grooves at both ends, and the grooves at both ends are respectively embedded in the two cathode steel bars.

[0030] Preferably, the material of the anti-displacement object in step (1) is metal, wood or hard plastic.

[0031] Preferably, the material of the anti-displacement object in step (1) is metal, wood or hard plastic; the material of the toothed positioning tool 1 and the toothed positioning tool 2 is a steel plate or an aluminum alloy plate with a thickness of 20 mm to 30 mm.

[0032] Preferably, the series welding in step (1) is performed by spot welding.

[0033] Preferably, the material of the C-shaped positioning strip in step (2) is metal, wood or hard plastic.

[0034] Preferably, the inter-electrode distance in step (3) is the horizontal distance between adjacent cathodes and anodes when they remain parallel.

[0035] Beneficial effects of the present invention:

[0036] The on-site installation and adjustment method proposed by the present invention is simple, easy to operate, and the positioning method is also easy to implement and popularize.

[0037] The present invention mainly provides a construction method for ensuring the pole distance between cathode steel rods and cathode plates before installing an oxygen-aluminum co-production electrolytic cell, which can prevent the pole distance from changing. At the same time, all the tools used mentioned in the present invention must be removed after the construction is completed. They are only tools for ensuring construction accuracy before construction, and no additional materials will be added, thus saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of using a toothed tool to vertically position the end of the cathode steel rod.

[0039] Figure 2 Schematic diagram of using toothed tool 2 to vertically position the middle part of the cathode steel rod.

[0040] Figure 3 Schematic diagram of horizontal positioning of anti-displacement objects.

[0041] Figure 4 This is a schematic diagram of positioning using steel rod series welding.

[0042] Figure 5 This is a schematic diagram of positioning adjacent cathode steel rod conductive rods using C-type positioning strips.

[0043] Figure 6 This is a schematic diagram of using a rangefinder to measure the distance and position the cathode plate.

[0044] Explanation of the reference numerals: 1-distance meter, 2-cathode plate, 3.1-toothed tool one, 3.2-toothed tool two, 4-conductive pile, 5-cathode steel rod, 5.1-end of cathode steel rod, 6-anti-displacement object, 7-welding bar, 8-C-type positioning bar. DETAILED DESCRIPTION

[0045] The present invention is further described below in conjunction with the accompanying drawings, but this does not limit the scope of protection thereof.

[0046] Embodiment 1:

[0047] A method for on-site installation, adjustment and positioning of a vertical cathode furnace for an oxygen-aluminum co-production electrolytic cell comprises the following steps:

[0048] (1) The oxygen-aluminum co-production electrolytic cell adopts vertically arranged inert anodes and inert cathodes, which are arranged alternately. The vertical anodes are suspended on the upper part of the electrolytic cell, and the vertical cathodes are placed on the bottom substrate of the electrolytic cell;

[0049] After the first layer of dry anti-seepage material in the oxygen-aluminum co-production electrolytic cell is vibrated and scraped flat, the cathode steel bars are installed. After all the cathode steel bars are placed, the center reference cathode steel bar is first adjusted and positioned using the anode and cathode automatic posture detection system, and then the level ruler is used to adjust and position it horizontally; after the first cathode steel bar is determined, it is used as the center reference and then the other cathode steel bars are adjusted and positioned on both sides;

[0050] The method of adjusting positioning is as follows:

[0051] A. Use a toothed tool to vertically position the end of the steel rod: Use a toothed tool to vertically position the end of the cathode steel rod. Insert the toothed tool vertically into the ends of two or more adjacent groups of cathode steel rods to position them (such as Figure 1 As shown), in order to prevent the cathode steel rod from displacement;

[0052] B. Use toothed tool 2 to vertically locate the middle part of the steel rod: Use toothed tool 2 to vertically locate two or more adjacent groups of cathode steel rods. Insert toothed tool 2 vertically into the middle part of two adjacent groups of cathode steel rods to position them (such as Figure 2 As shown), in order to prevent the displacement of the steel rod;

[0053] C. Use anti-displacement object horizontal positioning method: Use anti-displacement objects to prevent horizontal displacement of two adjacent cathode steel bars. Place the prefabricated anti-displacement object between the two adjacent steel bars (such as Figure 3 As shown), in order to prevent the steel bar from moving horizontally;

[0054] D. Use steel rod series welding positioning method: After the cathode steel rod is adjusted to the right position, that is, the cathode steel rod is perpendicular to the bottom of the electrolytic cell, and the cathode steel rods are parallel to each other; the cathode steel rods are welded in series at both ends, specifically by spot welding, to fix the cathode steel rod (such as Figure 4 As shown), prevent the cathode steel rod from horizontal or vertical displacement.

[0055] (2) Installation and positioning of cathode plate

[0056] Adopt C-type positioning strip method: after the cathode steel rod is adjusted and positioned in step (1), in order to further ensure the installation accuracy of the cathode plate and prevent the conductive rod from moving when the second layer of dry anti-seepage material is vibrated, use C-type positioning strips to position the cathode plate insertion positions of two or more adjacent cathode steel rods (such as Figure 5 shown);

[0057] (3) After the implementation of step (1) and step (2), when the second layer of dry anti-seepage material is laid in the oxygen-aluminum co-production electrolytic cell, the cathode steel rod will not be displaced during the vibration process or after being affected by external force, so as to ensure the accuracy of the installation of the cathode steel rod and ensure that the pole distance will not deviate; wherein the pole distance is the horizontal distance between adjacent cathodes and anodes when they are parallel;

[0058] (4) After the second layer of dry anti-seepage material is laid, remove the tools used for positioning and adjusting the cathode steel rod in step (1); including tooth positioning tool 1, tooth positioning tool 2, anti-displacement objects and materials used for series welding; and remove the C-shaped positioning strip in step (2);

[0059] (5) Distance measurement using a rangefinder: After the lining material of the electrolytic cell is completed, the cathode plates are installed. The middle group of cathode plates is selected as the reference surface for installation and positioning on both sides. After positioning, a micro laser rangefinder is used to measure the distance of the same part of the adjacent group of cathode plates using one end of the cathode plate as the reference surface (e.g. Figure 6 The tolerance is controlled within ±0.15mm.

[0060] Note: The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention; therefore, although this specification has described the present invention in detail with reference to the above embodiments, a person skilled in the art should understand that the present invention can still be modified or replaced by equivalents; and all technical solutions and improvements thereof that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for on-site installation, adjustment and positioning of a vertical cathode furnace for an oxygen-aluminum co-production electrolytic cell, characterized in that: The specific steps are as follows: the oxygen-aluminum co-production electrolytic cell adopts vertically arranged inert anodes and inert cathodes, the inert anodes and inert cathodes are arranged alternately, the vertical anodes are suspended on the upper part of the electrolytic cell, and the vertical cathodes are placed on the bottom substrate of the electrolytic cell; (1) After the first layer of dry anti-seepage material in the oxygen-aluminum co-production electrolytic cell is vibrated and scraped flat, the cathode steel bars are installed. After all the cathode steel bars are placed, the center reference cathode steel bar is first adjusted and positioned, and then a level ruler is used to adjust and position it horizontally. After the first cathode steel bar is determined, it is used as the center reference and then the other cathode steel bars are adjusted and positioned on both sides. The adjustment and positioning refers to ensuring that the two sides of the cathode are parallel and equidistant from the two sides of the anode. The specific method of adjusting the positioning is as follows: A. Use a toothed tool to vertically position the end of the steel rod: Use a toothed tool to vertically position the end of the cathode steel rod. Insert the toothed tool vertically into the ends of two or more adjacent groups of cathode steel rods to prevent the cathode steel rods from shifting. B. Use toothed tool 2 to vertically locate the middle part of the steel rod: Use toothed tool 2 to vertically locate two or more adjacent groups of cathode steel rods, insert toothed tool 2 into the middle part of two adjacent groups of cathode steel rods to lock them, so as to prevent the displacement of cathode steel rods; C. Use anti-displacement object horizontal positioning method: Use anti-displacement objects to prevent horizontal displacement of two adjacent cathode steel bars. The anti-displacement objects are stuck between the two adjacent cathode steel bars to limit the movement of the cathode steel bars, so as to prevent the cathode steel bars from moving horizontally. D. Use steel rod series welding positioning method: After the cathode steel rod is adjusted in place, that is, the cathode steel rod is perpendicular to the bottom of the electrolytic cell, and the cathode steel rods are parallel to each other; the cathode steel rods are welded in series at both ends, that is, the cathode steel rods are fixed by welding bars to prevent the cathode steel rods from horizontal or vertical displacement; C or D can be used alone, or A, B, C and D can be used in combination, in no particular order; the material of the toothed tool 1 and the toothed tool 2 is a steel plate or an aluminum alloy plate with a thickness of 20 mm to 30 mm; (2) Installation and positioning of cathode plate The C-type positioning bar method is adopted: after the cathode steel bar is adjusted and positioned in step (1), in order to further ensure the installation accuracy of the cathode plate and prevent the displacement of the conductive piles when the second layer of dry anti-seepage material is vibrated, the cathode plate insertion positions of two or more adjacent cathode steel bar conductive piles are positioned using C-type positioning bars; the conductive piles of the adjacent cathode steel bars are fixed by the C-type positioning bars to limit their displacement; the material of the C-type positioning bars is metal, wood or hard plastic; (3) After the implementation of step (1) and step (2), when the second layer of dry anti-seepage material is laid in the oxygen-aluminum co-production electrolytic cell, the cathode steel rod will not be displaced during the vibration process or after being affected by external force, so as to ensure the accuracy of the installation of the cathode steel rod and ensure that the pole distance will not deviate; the pole distance is the horizontal distance between adjacent cathodes and anodes when they are parallel to each other; (4) After the second layer of dry anti-seepage material is laid, remove the tools used for positioning and adjusting the cathode steel rod in step (1); including toothed tool 1, toothed tool 2, anti-displacement object and series welding strip; and simultaneously remove the C-shaped positioning strip in step (2); (5) Distance measurement method using a rangefinder: After the lining material of the electrolytic cell is completed, the cathode plates are installed. The middle group of cathode plates is selected as the reference plane for installation and positioning on both sides. After positioning, a micro laser rangefinder is used to measure the distance of the same part of an adjacent group of cathode plates using one end of the selected cathode plate as the reference plane. The tolerance is controlled within ±0.15 mm.

2. The method for on-site installation, adjustment and positioning of a vertical cathode furnace for oxygen-aluminum cogeneration electrolytic cell according to claim 1, characterized in that: The adjustment and positioning of the center reference cathode steel bar in step (1) is to use a visual system to determine the installation status of the cathode steel bar; the visual system is specifically an automatic detection system for the anode and cathode postures, including an anode template, a laser rangefinder, an industrial control computer and a software system.

3. The method for on-site installation, adjustment and positioning of a vertical cathode furnace for oxygen-aluminum cogeneration electrolytic cell according to claim 1, characterized in that: The shape of the anti-displacement object in step (1) is not limited, and it can be stuck between two adjacent cathode steel bars; the anti-displacement object can also be a device with grooves at both ends, and the grooves at both ends are respectively embedded in the two cathode steel bars.

4. The method for on-site installation, adjustment and positioning of a vertical cathode furnace for oxygen-aluminum cogeneration electrolytic cell according to claim 1, characterized in that: The anti-displacement object in step (1) is made of metal, wood or hard plastic.

5. The method for on-site installation, adjustment and positioning of a vertical cathode furnace for oxygen-aluminum cogeneration electrolytic cell according to claim 1, characterized in that: The series welding in step (1) is performed by spot welding.

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