Two-layer sintering boat device for rapidly recycling silver graphite leftover materials

Abstract

A two-layer sintering boat device for rapidly recycling silver graphite leftover materials comprises an upper-layer filtering sintering boat and a lower-layer carrier sintering boat which are matched up and down, the upper-layer filtering sintering boat comprises a loading groove used for loading materials, and a plurality of leaking holes used for recycling the silver graphite leftover materials to the lower-layer carrier sintering boat are formed in the bottom of the loading groove. And a recovery tank for bearing silver graphite leftover materials is arranged in the lower-layer carrier sintering boat. And the silver graphite extrusion leftover materials are loaded into the upper-layer sintering boat, and are heated and subjected to heat preservation in an air sintering furnace to obtain the recycled silver leftover materials. No other impurities are introduced into the silver leftover material recovered by the method, the silver leftover material can be directly used as a raw material to be transferred, and the recovery efficiency is high.

Description

Technical Field

[0001] The utility model relates to a two-layer sintering boat device for quickly recovering silver graphite scraps, belonging to the field of material recovery. Background Art

[0002] Silver-graphite materials offer excellent resistance to welding and low, stable contact resistance, with their resistance improving as the graphite content increases. Silver-graphite materials are typically used as static points and paired with materials such as Cu, AgNi, AgW, and AgWC in applications such as miniature circuit breakers (MCBs), molded case circuit breakers (MCCBs), residual current circuit breakers (RCDs), and motor starters.

[0003] Silver-graphite extrusion and slitting is a common process for producing silver-graphite contacts. The production process is broadly divided into: silver powder preparation (chemical / atomization) → Ag powder and C powder ratio → powder mixing → sintering → extrusion → slicing → decarburization → slitting → heat treatment → cleaning → finished product. Because the material needs to be slitting twice during the production process, the yield rate is low and a large amount of scrap is generated during the production process. Therefore, efficient recycling of silver-graphite scrap is of great significance for material recycling.

[0004] At present, the electrical alloy industry usually uses chemical and decarburization methods to recover silver from silver graphite scraps produced during the processing process. The decarburization method is to directly decarburize the silver graphite powder waste produced by slicing and cutting in the production process in a 600-900℃ air furnace under high temperature and oxygen to obtain silver scraps. For extruded rod-shaped and extruded cylindrical cake-shaped waste, the alloy block needs to be expanded and fractured at above 960℃ under a protective atmosphere. The remaining material after crushing is placed in a 600-900℃ air furnace and decarburized under high temperature and oxygen to obtain silver scraps.

[0005] Chemical methods for silver graphite recovery require a large amount of acid and alkali reagents, making recovery costs difficult to control. The process also produces significant amounts of waste gas and wastewater, significantly polluting the environment. Furthermore, because graphite is insoluble in chemical reagents, it absorbs some silver ions during the reaction, reducing recovery rates. Decarburization methods require long, high-temperature sintering cycles due to the high density of bulk silver graphite scrap. Utility Model Content

[0006] The purpose of the utility model is to overcome the shortcomings and deficiencies of the prior art and to provide a two-layer sintering boat device for quickly recovering silver graphite scraps.

[0007] A two-layer sintering boat device for the rapid recovery of silver-graphite scraps comprises an upper filter sintering boat and a lower carrier sintering boat arranged in a coordinated manner. The upper filter sintering boat comprises a loading trough for loading materials, the bottom of which is provided with a plurality of leak holes for recovering the silver-graphite scraps to the lower carrier sintering boat. The lower carrier sintering boat is provided with a recovery trough for carrying the silver-graphite scraps. The upper sintering boat is loaded with silver-graphite extruded scraps, which are heated and insulated in an air sintering furnace to obtain recycled silver scraps. The silver scraps recovered using this method are free of other impurities and can be directly used as raw materials, resulting in high recovery efficiency.

[0008] Preferably, the leak holes are funnel-shaped, larger at the top and smaller at the bottom, and are evenly distributed across the bottom of the filter tank. The bottom is provided with multiple leak holes, each shaped like a funnel with a larger top and a smaller bottom. This design can enhance the fluidity of the material. The larger-at-top, smaller-at-bottom shape effectively prevents large particles from clogging the leak holes, thereby ensuring that the scrap material flows smoothly into the lower recovery tank and reducing the occurrence of blockage. The even distribution of the leak holes ensures that the silver-graphite scrap material falls evenly throughout the entire filtration area, thereby improving the overall material recovery effect and efficiency.

[0009] Furthermore, the cross-sectional inclination angle of the leakage hole is 5° to 20°. The appropriate inclination angle allows the material to slide more easily under the action of gravity, thereby improving the material's self-flow and flow rate, and reducing sedimentation or accumulation caused by stagnation. This accelerates the filtration process, allowing more silver-graphite scraps to quickly pass through the leakage hole and enter the lower recovery tank, thereby improving overall filtration and recovery efficiency.

[0010] Preferably, support platforms are provided on both sides of the recovery tank, and the support platforms are used to support the upper filter sintering boat, and the inner wall of the support platforms is tilted inward. The design of the support platforms provides more stable support for the upper filter sintering boat, reduces shaking or tilting during operation, and thus improves the overall stability and safety of the equipment. The inclined design of the inner wall of the support platform promotes the flow of silver-graphite scraps in the recovery tank, and the material can flow downward into the recovery tank more smoothly, avoiding accumulation and blockage, making the recovery process more efficient, and preventing a large amount of graphite from entering the lower sintering boat.

[0011] Furthermore, the support platform has an inclination angle of 5° to 20° to ensure that the upper filter sintering boat can be placed stably, and the side is set at an inclination angle to ensure that the metal plate can be smoothly removed after cooling and solidification.

[0012] Furthermore, a hole groove is provided on the inner wall of the recovery tank along the length direction, and the hole groove is located on both sides of the support platform. The top of the hole groove and the highest point of the support platform are located at the same horizontal plane. The length of the hole groove does not exceed the distance between the support platforms on both sides, thereby increasing the air flow inside the sintering boat and accelerating the oxidation of graphite.

[0013] Preferably, the upper filter sinter boat further comprises handles provided on both sides of the loading slot, wherein the handles are provided in the form of bosses. The maximum height of a single loading cannot exceed the handles to prevent the melted silver from overflowing from the side holes.

[0014] Preferably, the upper filter sintered boat and the lower carrier sintered boat are made of high-quality graphite, alumina, or zirconia. These materials, along with their excellent high-temperature resistance, maintain their shape and performance during high-temperature sintering, ensuring safe and stable operation of the equipment in high-temperature environments. They also exhibit excellent corrosion resistance, effectively resisting chemical components potentially present in silver-graphite scrap, extending the equipment's service life and reducing maintenance frequency.

[0015] The beneficial effects of the present invention are as follows: (1) The recycling process of silver-graphite scraps is simplified, shortening the material cycle time. (2) No new environmental pollutants are generated during the recycling process. (3) The equipment used for recycling is an air sintering furnace, which reduces the recycling cost. (4) The amount of scrap input per time can be increased by designing and adjusting the mold, and the recycling efficiency can be guaranteed by changing the temperature and holding time, and it can be adapted to different heating recycling equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0017] Figure 1 This is a schematic diagram of the main structure of the utility model;

[0018] Figure 2 Schematic diagram of the structure of the upper filtering sintered boat;

[0019] Figure 3 Schematic diagram of the structural cross section of the upper filtering sintered boat;

[0020] Figure 4 Schematic diagram of the structure of the lower carrier sintering boat;

[0021] In the figure, 1. upper filter sintering boat; 11. loading tank; 12. leakage hole; 13. handle; 2. lower carrier sintering boat; 21. recovery tank; 22. support platform; 23. hole slot. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in further detail below with reference to the accompanying drawings.

[0023] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two non-identical entities or non-identical parameters with the same name. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. Subsequent embodiments will not explain this one by one.

[0024] The directional and positional terms used in this invention, such as "upper," "lower," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side," are used solely to refer to the directions or positions in the accompanying drawings. Therefore, the directional and positional terms used are intended to illustrate and facilitate understanding of this invention and are not intended to limit the scope of protection of this invention.

[0025] like Figure 1-4 As shown, an embodiment of the utility model is a two-layer sintering boat device for rapid recovery of silver-graphite scraps, comprising an upper filter sintering boat 1 and a lower carrier sintering boat 2 matched with each other. The upper filter sintering boat 1 comprises a loading tank 11 for loading materials, and a plurality of leakage holes 12 are provided at the bottom of the loading tank 11 for recovering the silver-graphite scraps to the lower carrier sintering boat 2. The lower carrier sintering boat 2 is provided with a recovery tank 21 for carrying the silver-graphite scraps. Silver-graphite extruded scraps are loaded into the upper sintering boat, and heated and kept warm in an air sintering furnace to obtain recovered silver scraps. The silver scraps recovered by this method do not have other impurities brought in and can be directly used as raw materials, with high recovery efficiency.

[0026] The leakage holes 12 are funnel-shaped, larger at the top and smaller at the bottom, and are evenly distributed at the bottom of the filter tank. The bottom is provided with multiple leakage holes 12, which are funnel-shaped, larger at the top and smaller at the bottom. This design can enhance the fluidity of the material. The shape of larger at the top and smaller at the bottom can effectively prevent large particles from clogging the leakage holes 12, thereby ensuring that the scraps can flow smoothly into the lower recovery tank 21, reducing the occurrence of blockage. The uniform distribution of the leakage holes 12 can ensure that the silver-graphite scraps can fall evenly throughout the entire filtration area, thereby improving the overall material recovery effect and efficiency.

[0027] The cross-sectional angle of the leakage hole 12 is 5° to 20°. The appropriate inclination angle allows the material to slide more easily under the action of gravity, thereby improving the material's self-flow and flow rate and reducing sedimentation or accumulation caused by stagnation. This accelerates the filtration process, allowing more silver-graphite scraps to quickly pass through the leakage hole 12 and enter the lower recovery tank 21, thereby improving overall filtration and recovery efficiency.

[0028] Support platforms 22 are provided on both sides of the recovery tank 21. The support platforms 22 are used to support the upper filter sintering boat 1. The inner wall of the support platform 22 is tilted inward. The design of the support platform 22 provides a more stable support for the upper filter sintering boat 1, reduces shaking or tilting during operation, and thus improves the overall stability and safety of the equipment. The inclined design of the inner wall of the support platform 22 promotes the flow of silver-graphite scraps in the recovery tank 21. The material can flow downward into the recovery tank 21 more smoothly, avoiding accumulation and blockage, making the recovery process more efficient and preventing a large amount of graphite from entering the lower sintering boat.

[0029] The tilt angle of the support platform 22 is 5° to 20° to ensure that the upper filter sintering boat 1 can be placed stably, and the side is set at a tilt angle to ensure that the metal plate can be smoothly removed after cooling and solidification.

[0030] The inner wall of the recovery tank 21 is provided with a hole groove 23 along the length direction. The hole groove 23 is located on both sides of the support platform 22. The top of the hole groove 23 and the highest point of the support platform 22 are located at the same horizontal plane. The length of the hole groove 23 does not exceed the distance between the support platforms 22 on both sides, thereby increasing the air flow inside the sintering boat and accelerating the oxidation of graphite.

[0031] The upper filter sintered boat 1 further includes handles 13 on both sides of the loading slot 11. The handles 13 are protruding bosses. The maximum height of a single loading cannot exceed the handles 13 to prevent the melted silver from overflowing from the side holes 23.

[0032] The upper filter sintered boat 1 and the lower carrier sintered boat 2 are made of high-quality graphite, alumina, or zirconia. These materials, along with their excellent high-temperature resistance, maintain their shape and performance during high-temperature sintering, ensuring safe and stable operation of the equipment in high-temperature environments. They also exhibit excellent corrosion resistance, effectively resisting chemical components potentially present in silver-graphite scrap, extending the equipment's service life and reducing maintenance frequency.

[0033] During use, the powdered scraps produced by silver-graphite cutting are isostatically pressed into blocks. These blocks are then placed in the upper filter sintering boat (1) and held at a temperature above 1000°C for 4 hours in an air atmosphere. After cooling, the upper filter sintering boat (1) is removed to yield the lower silver cake. Other strips, cakes, and flakes can be directly placed in the upper filter sintering boat (1) for heating and separation.

[0034] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

[0035] Although the present invention has been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the specific embodiments disclosed, and the present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A two-layer sintering boat device for rapid recovery of silver-graphite scrap, characterized by: It includes an upper filter sintered boat and a lower carrier sintered boat that are matched with each other. The upper filter sintered boat includes a loading trough for loading materials. The bottom of the loading trough is provided with a plurality of leakage holes for recovering silver graphite scraps to the lower carrier sintered boat. The lower carrier sintered boat is provided with a recovery trough for carrying silver graphite scraps.

2. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 1, characterized in that: The leakage holes are in the shape of a funnel with a larger top and a smaller bottom, and are evenly distributed at the bottom of the filter tank.

3. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 2, characterized in that: The inclination angle of the cross section of the leakage hole is 5° to 20°.

4. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 1, characterized in that: Support platforms are provided on both sides of the recovery tank, and the support platforms are used to support the upper filtering sintering boat. The inner walls of the support platforms are inclined inwards.

5. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 4, characterized in that: The tilt angle of the support platform is 5° to 20°.

6. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 4, characterized in that: The inner wall of the recovery tank is provided with a hole groove along the length direction. The hole groove is located on both sides of the bracket platform. The top of the hole groove and the highest point of the bracket platform are located in the same horizontal plane. The length of the hole groove does not exceed the distance between the bracket platforms on both sides.

7. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 1, characterized in that: The upper filtering sintered boat further comprises handles arranged on both sides of the loading slot, and the handles are arranged in the form of bosses.

8. The two-layer sintering boat device for rapid recovery of silver-graphite scrap according to claim 1, characterized in that: The materials of the upper filter sintered boat and the lower carrier sintered boat are three high graphite, alumina or zirconia.

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