Cathode carbon block and steel bar assembling structure

Abstract

The utility model belongs to the technical field of aluminum electrolysis, and particularly relates to a cathode carbon block and steel bar assembling structure which comprises a full-graphite cathode carbon block and a steel bar, at least one steel bar groove is formed in the full-graphite cathode carbon block in a penetrating mode, a leveling layer is arranged on the bottom wall of the steel bar groove, and the steel bar groove is formed in the full-graphite cathode carbon block in a penetrating mode. Two steel bars are symmetrically arranged in the steel bar groove at a fixed interval, and the bottom ends of the steel bars are tightly attached to the leveling layer. A partition layer is arranged in a steel bar groove between the two steel bars, and gaps between the side walls of the steel bars and the steel bar groove are sequentially filled with an inner filling layer and an outer filling layer from inside to outside. According to the structure, the convention is broken, two cathode paste materials are adopted, the cathode carbon block is assembled in a composite mode, compared with a traditional cathode assembly structure, the composite assembly structure can better achieve the effects of restraining horizontal current, reducing the surface conductive resistance of a cathode steel bar and obtaining lower furnace bottom pressure drop during operation of an electrolytic cell, and meanwhile cost is greatly reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of aluminum electrolysis, and particularly relates to an assembly structure of a cathode carbon block and a steel bar. Background Art

[0002] The assembly of cathode carbon blocks is one of the key links in the construction of aluminum electrolysis cells. Different cathode assembly methods and the selection of assembly pastes determine different assembly effects, resulting in different voltage drops in the assembly of cathode carbon blocks, which in turn affect key indicators such as the voltage drop at the bottom of the cell and the power consumption per ton of aluminum during the operation of the electrolysis cell.

[0003] Currently, the combination methods of cathode carbon blocks and cathode bars in aluminum electrolysis cells are divided into two ways: cathode paste ramming and cast iron pouring. Among them, the cast iron pouring method requires a high-temperature process of 1400 °C (such as phosphorus pig iron casting), with a large thermal shock, which easily causes cracks in the carbon blocks, a high scrap rate, and high costs. When using the cathode paste ramming method, currently, a high-conductivity cathode paste (or cold ramming paste) mainly using graphite and electrically calcined anthracite as aggregates is mainly used, and its normal temperature resistivity is usually between 25 μΩ·m and 40 μΩ·m. This method is not conducive to reducing the horizontal current and cathode voltage drop of the electrolysis cell.

[0004] Conventional cathode carbon block assembly methods generally only use one type of paste to ram and assemble the cathode carbon blocks. The assembly has the following problems: the method has been basically finalized and there is no room for improvement, the voltage drop at the bottom of the cell during the operation of the electrolysis cell after assembly is relatively high, and the cost is difficult to control.

[0005] In order to reduce the horizontal current and cathode voltage drop of the electrolysis cell, currently, a paste containing metal particles selected from copper, nickel, iron, and their mixtures or alloys is used. By using this type of paste to connect the cathode carbon block and the steel bar, however, this type of metal particle paste is often extremely costly, with a price of about 30,000 yuan per ton, while the price of traditional cold ramming paste is only about 10,000 yuan per ton. Therefore, how to further save costs on the basis of reducing the horizontal current and cathode voltage drop of the electrolysis cell is a technical problem that needs to be solved. Summary of the Utility Model

[0006] Aiming at the technical problems existing in the background art, the utility model provides an assembly structure of a cathode carbon block and a steel bar, which can further save costs on the basis of reducing the horizontal current and cathode voltage drop of the electrolysis cell.

[0007] To achieve the above object, the technical solution provided by the utility model is as follows:

[0008] An assembly structure of a cathode carbon block and a steel rod, including a fully graphitic cathode carbon block and a steel rod. At least one steel rod groove is penetrated and opened on the fully graphitic cathode carbon block. In the present utility model, preferably two steel rod grooves are opened. A leveling layer is provided on the bottom wall of the steel rod groove. Two steel rods are symmetrically arranged in the steel rod groove at a fixed distance apart, and the bottom ends of the steel rods are closely attached to the leveling layer. A partition layer is arranged in the steel rod groove between the two steel rods. An internal filling layer and an external filling layer are sequentially filled in the gap between the side wall of the steel rod and the steel rod groove from the inside to the outside.

[0009] Further, an end filling layer is filled inside the end of the gap between the side wall of the steel rod and the steel rod groove, and the inner side of the end filling layer is closely attached to the internal filling layer and the external filling layer.

[0010] Further, the materials of the leveling layer, the partition layer, the end filling layer and the external filling layer are the same, all of which are cold ramming paste. The cold ramming paste adopts existing technical materials. The cold ramming paste is a carbonaceous filling raw material for masonry. Electrically calcined coal and artificial graphite are mainly selected as the aggregate for preparing the cold ramming paste, and it is widely used in industrial furnaces such as aluminum electrolysis cells, blast furnaces, smelting furnaces, and calcium carbide furnaces. The material of the internal filling layer is a metal particle paste containing metal particles selected from copper, nickel, iron and their mixtures or alloys. Using metal particles or metal powders as cathode paste is also a conventional technical choice. There is better thermal matching among the cathode carbon block, the internal filling layer and the steel rod. The interfacial bonding strength between the steel rod and the cathode carbon block is higher, significantly reducing the contact resistance between the steel rod and the carbon block. At the same time, the internal filling layer itself also has good electrical conductivity. Therefore, the steel rod - cathode carbon block assembled with this ramming paste has a significant effect on reducing the cathode voltage drop, is also beneficial to extending the service life of the cathode, and increasing production efficiency.

[0011] In the present utility model, the assembly structure of the cathode carbon block and the steel rod further includes a U-shaped baffle. The width of the baffle is the same as the width of the steel rod groove. The baffle is fitted and inserted into the steel rod groove, and the two-by-two tied baffles are arranged at a fixed distance apart for tying to form a partition layer and an end filling layer.

[0012] Further, the number of baffles is four.

[0013] Further, the partition layer, the end filling layer and the external filling layer are flush with the steel rod.

[0014] The present utility model has the following advantages and beneficial effects:

[0015] The present utility model provides an assembly structure of a cathode carbon block and a steel rod. In this structure, the combination of the cathode carbon block and the steel rod is fixed by cathode paste. By setting a leveling layer, the positioning and installation of the steel rod can be accurately achieved to ensure the levelness. At the same time, multiple pastes are set. The materials of the leveling layer, the isolation layer, the end filling layer, and the external filling layer are the same, all being cold ramming paste. The material of the internal filling layer is a paste containing metal particles selected from copper, nickel, iron, and their mixtures or alloys. The internal filling layer is wrapped and protected by the leveling layer, the isolation layer, the end filling layer, and the external filling layer. A connection structure combining two pastes is adopted. By using the internal filling layer as a paste containing metal particles, it can better suppress the horizontal current, reduce the surface conduction resistance of the cathode steel rod, and obtain the effect of a lower bottom voltage drop during the operation of the electrolytic cell. At the same time, the structure of combining two pastes can greatly reduce the usage amount of the internal filling layer, thereby saving costs significantly while reducing the voltage drop.

[0016] In summary, this structure breaks the convention and adopts two types of cathode pastes for the composite assembly of the cathode carbon block. Compared with the traditional cathode assembly structure, the composite assembly can better suppress the horizontal current, reduce the surface conduction resistance of the cathode steel rod, and obtain the effect of a lower bottom voltage drop during the operation of the electrolytic cell, while greatly reducing the cost. Brief Description of the Drawings

[0017] Figure 1 is a cross-sectional view of the cathode carbon block provided by the present utility model;

[0018] Figure 2 is Figure 1 the bottom view of

[0019] Figure 3 is a structural diagram of the baffle for fixing provided by the present utility model;

[0020] Figure 4 is a cross-sectional view of the cathode carbon block, the steel rod, the leveling layer, and the isolation layer provided by the present utility model;

[0021] Figure 5 is Figure 4 the bottom view of

[0022] Figure 6 is an installation schematic diagram of the cathode carbon block, the steel rod, and the baffle provided by the present utility model;

[0023] Figure 7 is a schematic diagram of the assembly structure of the cathode carbon block and the steel rod provided by the present utility model;

[0024] Reference Signs: 1 - cathode carbon block, 11 - steel rod groove, 2 - steel rod, 3 - leveling layer, 4 - isolation layer, 5 - baffle for fixing, 6 - end filling layer, 7 - internal filling layer, 8 - external filling layer. Detailed Description of the Preferred Embodiments

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model.

[0026] Therefore, the detailed description of the embodiments of the present utility model provided in the accompanying drawings is not intended to limit the scope of the present utility model claimed, but merely represents the selected embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model.

[0027] Embodiment

[0028] As Figures 1-7 shown, an assembly structure of a cathode carbon block and a steel rod includes a fully graphite cathode carbon block 1 and a highly conductive steel rod 2. At least one steel rod groove 11 is penetrated and opened on the fully graphite cathode carbon block 1. In the present utility model, it is preferably provided with two steel rod grooves 11. A leveling layer 3 is provided on the bottom wall of the steel rod groove 11. Two steel rods 2 are symmetrically arranged at a fixed distance apart in the steel rod groove 11, and the bottom ends of the steel rods 2 are tightly attached to the leveling layer 3; a partition layer 4 is provided in the steel rod groove 11 between the two steel rods 2. An inner filling layer 7 and an outer filling layer 8 are sequentially filled in the gap between the side wall of the steel rod 2 and the steel rod groove 11 from the inside to the outside.

[0029] Further, an end filling layer 6 is filled inside the end of the gap between the side wall of the steel rod 2 and the steel rod groove 11, and the inner side of the end filling layer 6 is tightly attached to the inner filling layer 7 and the outer filling layer 8.

[0030] Further, the leveling layer 3, the isolation layer 4, the end filling layer 6 and the outer filling layer 8 are made of the same material, which is cold ramming paste. The cold ramming paste uses existing technology materials. The cold ramming paste is a carbon filling raw material for masonry, and mainly selects electrically calcined coal and artificial graphite as the aggregate for preparing the cold ramming paste. This material is widely used in industrial furnaces such as aluminum electrolytic cells, iron blast furnaces, smelting furnaces, and calcium carbide furnaces. The material of the internal filling layer 7 is a metal particle paste containing metal particles selected from copper, nickel, iron, and their mixtures or alloys. Metal particles or metal powders are used as the cathode paste. There is better thermal matching among the cathode carbon block 1, the internal filling layer 7, and the steel bar 2. The interfacial bonding strength between the steel bar 2 and the cathode carbon block 1 is higher, significantly reducing the contact resistance between the steel bar and the carbon block. At the same time, the internal filling layer 7 itself also has good electrical conductivity. Therefore, the assembly of the steel bar 2 - cathode carbon block 1 using this ramming paste has a significant effect on reducing the cathode voltage drop, is also beneficial to extending the service life of the cathode, and increasing production efficiency; while the leveling layer 3, the isolation layer 4, the end filling layer 6 and the outer filling layer 8 are made of the same material, which is cold ramming paste, wrapping the inner side, playing a role in protection and connection, and can reduce the amount of the internal filling layer 7, so as to greatly reduce the consumption of high-cost cathode paste on the premise of meeting the requirement of reducing the voltage drop.

[0031] In the present utility model, for the composite assembly structure of the cathode carbon block 1 for an aluminum electrolytic cell, it further includes a U-shaped fixing baffle. The width of the baffle is the same as the width of the steel bar groove 11. The baffle is inserted and fitted in the steel bar groove 11. Two fixing baffles 5 are arranged at a fixed distance apart for fixing to form the isolation layer 4 and the end filling layer 6.

[0032] Further, the number of the fixing baffles is four.

[0033] Further, the steel bars 2 in the isolation layer 4, the end filling layer 6 and the outer filling layer 8 are arranged flush.

[0034] The fixing process of the cathode carbon block 1 and the steel bar 2:

[0035] As Figure 6 shown, the number of the special fixing baffles 5 is four. First, install and fix two special fixing baffles 5 at the two ends of the all-graphite cathode carbon block 11 (these baffles will be removed after all assemblies are completed), and ram a layer of leveling layer 3 as a bottom pad to level the high-conductivity cathode steel bar 2. Then place two sections of high-conductivity cathode steel bars 2 on the leveling layer 3 (the first layer of paste) in the steel bar groove 11 of the cathode carbon block 1, and level and fasten them.

[0036] Install and fix the other two special fixing baffles 5 at the middle position between the two sections of high-conductivity cathode steel bars 2, and ram the isolation layer 4 in six layers between the two sections of high-conductivity steel bars 2. After ramming, remove these two special fixing baffles 5.

[0037] As Figure 7As shown, a special fixing baffle 5 is installed and fixed again at a certain distance from both ends of the cathode carbon block 1. After the internal filling layer 7 is fixed on both sides of the highly conductive steel bar 2 in four layers, this special fixing baffle is removed (that is, in the gap between the steel bar 2 and the steel bar groove 11, an internal filling layer 7 with a certain depth is fixed).

[0038] Finally, the end filling layers 6 at both ends of the cathode carbon block 1 are fixed in six layers, and then the external filling layer 8 on the upper surface of the cathode carbon block 1 is fixed in two layers, covering the internal filling layer 7, so that the cold ramming paste (end filling layer 6, external filling layer 8, leveling layer 3, and isolation layer 4) wraps around the cathode steel bar to form a relatively closed space.

[0039] During the fixing process, strictly control the fixing compression ratio and fixing wind pressure of each type of paste, and strictly construct according to the assembly operation standard to obtain high-quality composite fixing quality of the cathode carbon block 1.

[0040] The present utility model provides an assembly structure of a cathode carbon block and a steel bar. In this structure, the combination method of the cathode carbon block and the steel bar is cathode paste fixing. By setting a leveling layer, the positioning and installation of the steel bar can be accurately realized to ensure the levelness; at the same time, multiple types of pastes are set. The materials of the leveling layer, isolation layer, end filling layer, and external filling layer are the same, all being cold ramming paste; the material of the internal filling layer is a metal particle paste containing metal particles selected from copper, nickel, iron, and their mixtures or alloys. The internal filling layer is wrapped and protected by the leveling layer, isolation layer, end filling layer, and external filling layer. A connection structure combining two types of pastes is adopted. By using the internal filling layer as a metal particle paste, it can better inhibit the horizontal current, reduce the surface conduction resistance of the cathode steel bar, and obtain the effect of lower bottom voltage drop during the operation of the electrolytic cell. At the same time, the structure of combining two types of pastes can greatly reduce the usage quantity of the internal filling layer, thereby greatly saving costs while reducing the voltage drop.

[0041] In summary, this structure breaks the convention and adopts two types of cathode pastes for the composite assembly of the cathode carbon block. Compared with the traditional cathode assembly structure, the composite assembly can better inhibit the horizontal current, reduce the surface conduction resistance of the cathode steel bar, and obtain the effect of lower bottom voltage drop during the operation of the electrolytic cell, while greatly reducing the cost.

[0042] The above is only the preferred embodiment of the present utility model and is not used to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. An assembly structure of a cathode carbon block and a steel bar, characterized in that : Including all-graphite cathode carbon blocks and steel rods, At least one steel rod groove is provided through the full graphite cathode carbon block, a leveling layer is provided on the bottom wall of the steel rod groove, two steel rods are symmetrically provided at a fixed distance in the steel rod groove, and the bottom ends of the steel rods are closely attached to the leveling layer; A partition layer is arranged in the steel bar groove between the two steel bars, and the gap between the side wall of the steel bar and the steel bar groove is filled with an inner filling layer and an outer filling layer in sequence from inside to outside.

2. The assembly structure of the cathode carbon block and the steel bar according to claim 1, characterized in that: The end of the gap between the side wall of the steel bar and the steel bar groove is filled with an end filling layer, and the inner side of the end filling layer is arranged closely to the inner filling layer and the outer filling layer.

3. The assembly structure of the cathode carbon block and the steel bar according to claim 2, characterized in that: The materials of the leveling layer, the partition layer, the end filling layer and the external filling layer are the same, which are all cold-rammed pastes; the material of the internal filling layer is a metal particle paste selected from copper, nickel, iron and mixtures or alloys thereof.

4. The assembly structure of the cathode carbon block and the steel bar according to claim 3, characterized in that: It also includes a U-shaped baffle, the width of which is consistent with the width of the steel rod groove. The baffles are inserted into the steel rod groove in cooperation, and the baffles are arranged at a fixed distance for fastening in pairs to form a partition layer and an end filling layer.

5. The assembly structure of the cathode carbon block and the steel bar according to claim 4, characterized in that: The number of the baffles is four.

6. The assembly structure of the cathode carbon block and the steel bar according to claim 5, characterized in that: The steel bars of the partition layer, the end filling layer and the outer filling layer are arranged flush with each other.

Images