Graphite crucible and method for gas-based reduction metallurgy

Abstract

The embodiment of the invention relates to a graphite crucible and method for gas-based reduction metallurgy, and belongs to the technical field of metallurgical reactors. The embodiment of the invention aims at solving the technical problems that an existing graphite crucible is long in production period and low in reducing gas utilization rate in gas-based reduction metallurgy. The graphite crucible for the gas-based reduction metallurgy comprises a graphite crucible body, gas guide covers are arranged at the two ends of the graphite crucible body, and dense sieve-shaped through holes are formed in the gas guide covers. According to the embodiment of the invention, the graphite crucible plays a role of a charging container and a heating body in the smelting process, and meanwhile, through the design of the bulges and the sieve-shaped through hole gas flow guide cover, reducing gas entering the graphite crucible can generate backflow instead of being directly discharged and is fully dispersed in the graphite crucible, so that the smelting efficiency is improved. The redundant unreacted gas is reused to participate in the reaction, so that the reaction gas can be fully utilized, the waste is reduced, and the utilization rate of the reducing gas is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of metallurgical reactors, and in particular to a graphite crucible and method for gas-based reduction metallurgy. Background Art

[0002] Graphite has excellent thermal conductivity and high temperature resistance, a small thermal expansion coefficient in a high temperature environment, high stability under conditions of rapid heating and cooling, and excellent chemical stability, and will not react to strong acid and alkali solutions. Graphite crucibles are made of flaky crystalline graphite, which is prepared through a series of processes including high temperature calcination, machine pressing, and resin binder. They have very stable chemical properties, high temperature resistance, oxidation resistance, and low ash content. They are widely used in high-purity metal smelting. They can be used as both a loading container and a heating element, and they do not participate in any chemical reactions during the smelting process, causing less pollution to the metal. Therefore, graphite crucibles are widely used in the smelting of iron metals and the smelting of non-ferrous metals and their alloys.

[0003] In the process of gas-based reduction metallurgy, in addition to the process parameters of the control system such as heating and insulation and the reaction gas flow rate, the design of the crucible also has a great influence on the consumption of reducing gas in the smelting process. The graphite crucible currently used has evolved from a single crucible, a double crucible to a suspension crucible. In the metallurgical process, it only plays the role of a loading container and a heating element. It has the disadvantages of slow heat transfer, low utilization of the reduction reaction gas, and a long smelting production cycle, which is not conducive to improving production efficiency and reducing costs.

[0004] The existing Chinese utility model patent with publication number CN202792949U discloses that the main body of the graphite crucible is designed to be cylindrical, and the inner wall of the crucible is at a certain angle to the axial direction of the crucible. The structure is simple and the processing is convenient, which can realize the convenient placement and removal of the suspended crucible, but the problem of waste of reducing gas is not solved. The existing publication number is CN2594275Y, and the name is "graphite crucible assembly". The patent discloses a graphite crucible assembly, including a crucible and a crucible cover. The interior of the crucible is an annular groove with a through hole in the center. There are two crucibles, which are concentrically arranged up and down. A crucible cover is provided between the upper and lower crucibles, and a crucible cover is provided on the upper part of the upper crucible; the patent discloses a typical crucible currently used, which can facilitate the extraction of smelting materials, but still does not solve the problem of waste of reducing gas. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a graphite crucible and method for gas-based reduction metallurgy, which can enable the reducing reaction gas to disperse and diffuse in the graphite crucible while forming a reflux, so that the reducing gas is in full contact with the material, thereby improving the production capacity, so as to solve the technical problems of long production cycle and low utilization rate of reducing gas in existing graphite crucibles in gas-based reduction metallurgy.

[0006] A first aspect of an embodiment of the present application provides a graphite crucible for gas-based reduction metallurgy, comprising a graphite crucible body, gas guide covers being arranged at both ends of the graphite crucible body, and dense sieve-like through holes being arranged on the gas guide covers.

[0007] In some embodiments that may include the above embodiments, the gas guide cover is protruded toward the inside of the graphite crucible body, the protrusion is adapted to the port of the graphite crucible body, the protruding portion is connected to the gas guide cover, and dense sieve-like through holes are also arranged around the protruding portion.

[0008] In some embodiments that may include the above embodiments, the protrusion is a cylindrical cone-shaped structure.

[0009] In some embodiments that may include the above embodiments, the graphite crucible body is a cylindrical structure with two ends open, and an accommodating space for loading materials is reserved between the gas guide cover and the graphite crucible body.

[0010] In some embodiments that may include the above embodiments, an external thread is further provided around the protrusion, an internal thread matching the external thread is provided on the port of the graphite crucible body, and the protrusion and the graphite crucible body are threadedly connected.

[0011] In some embodiments, which may include the above embodiments, the diameter of the through hole is less than 10 mm.

[0012] A second aspect of the embodiment of the present application further provides a method for gas-based reduction metallurgy, using the above-mentioned graphite crucible for gas-based reduction metallurgy, comprising the following steps:

[0013] First, install the lower gas guide cover on the bottom of the graphite crucible body, so that the reaction gas is dispersed into the graphite crucible through the side through holes around the lower gas guide cover, load the material in the graphite crucible, fix the upper gas guide cover on the top of the graphite crucible body, and the excess gas that does not participate in the reaction flowing into the graphite crucible will not directly flow out of the crucible due to the obstruction of the upper gas guide cover. After the obstruction, the excess reaction gas flow forms a reflux in the crucible and contacts with the material again to participate in the reaction. After the reaction is completed, remove the gas guide cover and pour the material out of the graphite crucible body.

[0014] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0015] 1. Improve the utilization rate of reducing gas: In the embodiment of the present application, the graphite crucible acts as a loading container and a heating element in the smelting process. Through the design of the protrusion and the sieve-shaped through-hole gas guide cover, the reducing gas entering the graphite crucible is not directly discharged, but refluxed and fully dispersed in the graphite crucible, so that the excess unreacted gas is reused to participate in the reaction, so that the reaction gas can be fully utilized, waste is reduced, the utilization rate of the reducing gas is improved and the cost is reduced;

[0016] 2. Effectively improve production efficiency and further reduce costs: The graphite crucible in the embodiment of the present application can make the reducing gas and the material fully contact in the metallurgical process, shorten the smelting production cycle, reduce the amount of reducing gas while ensuring the reduction reaction effect, effectively improve production efficiency and further reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a schematic diagram of gas flow and dispersion in a graphite crucible according to an embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of the side structure of the gas guide cover according to an embodiment of the present application;

[0020] Figure 3 This is a schematic diagram of the front structure of the gas guide cover according to an embodiment of the present application;

[0021] Figure 4 This is a real photo of the graphite crucible in the embodiment of the present application.

[0022] Description of reference numerals:

[0023] 1. Graphite crucible body; 2. Gas guide cover; 3. Protrusion; 4. Through hole. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] It needs to be explained that gas-based reduction metallurgy refers to a method of producing metals by using a gas reducing agent to undergo a reduction reaction with metal oxides under high temperature conditions. Compared with other methods, such as carbon reduction method and zinc reduction method, this method has the advantages of easier control of product properties and higher purity. Gaseous reducing agents include hydrogen (H2), carbon monoxide (CO) or other gaseous hydrocarbons, etc., which are used to reduce oxides to produce metal powders such as iron, copper, molybdenum, etc. Gas-based reduction metallurgy has a wide range of applications, and examples of metallurgical applications include hydrogen reduction of oxides to produce metal powders. In addition, the gas reduction method also includes gas-based direct reduction ironmaking, which is a direct reduction continuous steelmaking method that uses reducing gas as a reducing agent to reduce iron ore, and has industrial production significance.

[0026] Unless otherwise specified, the experimental methods used in the examples of this application are all conventional methods.

[0027] In the following examples, unless otherwise specified, all raw materials can be obtained by commercial purchase or conventional methods.

[0028] Example 1

[0029] like Figure 1-4 As shown, an embodiment of the present application provides a graphite crucible for gas-based reduction metallurgy, including a graphite crucible body 1, gas guide covers 2 are arranged at both ends of the graphite crucible body 1, and dense sieve-like through holes 4 are arranged on the gas guide cover 2, and the diameter of the through holes 4 is preferably less than 10 mm, and more preferably less than 5 mm; the through holes 4 prevent the graphite crucible from leaking after loading, and can ensure that the reaction gas can flow into the graphite crucible from the gas guide cover below and flow out from the gas guide cover above.

[0030] Furthermore, a protrusion 3 is provided on the gas flow guide cover 2 toward the inside of the graphite crucible body 1, the protrusion 3 is adapted to the port of the graphite crucible body 1, the protrusion 3 is connected to the gas flow guide cover 2, and dense sieve-like through holes 4 are also provided around the protrusion 3. When the reaction gas enters the graphite crucible through the through holes 4 around the flow guide cover 2 below (i.e., the side), the through holes will disperse the gas flow, promote the contact between the reaction gas and the material in the graphite crucible, and help improve the reaction efficiency. Exemplarily, the protrusion 3 is a cylindrical structure, the graphite crucible body 1 is a cylindrical structure with openings at both ends, and a storage space for loading materials is left between the upper and lower gas flow guide covers 2 and the graphite crucible body 1.

[0031] Specifically, an external thread is provided around the protrusion 3, and an internal thread matching the external thread is provided at the port of the graphite crucible body 1, and the protrusion 3 is threadedly connected to the graphite crucible body 1. After being assembled together, the upper and lower gas guide covers 2 are tightly assembled with the graphite crucible body 1, which is convenient for assembly and disassembly, ensuring that the loading does not leak and the material is also convenient for taking out.

[0032] When in use, the air flow enters from the gas guide cover below the graphite crucible. After reacting with the material, the unreacted gas is blocked by the gas guide cover above and cannot flow out of the graphite crucible directly. A reflux is formed inside the graphite crucible to react with the material again, ensuring full utilization of the reaction gas and reducing waste of reaction gas.

[0033] Example 2

[0034] The present application embodiment provides a method for gas-based reduction metallurgy, using the graphite crucible for gas-based reduction metallurgy in embodiment 1, comprising the following steps:

[0035] First, install the lower gas guide cover on the bottom of the graphite crucible body, so that the reaction gas is dispersed into the graphite crucible through the side through holes around the lower gas guide cover, load the material in the graphite crucible, fix the upper gas guide cover on the top of the graphite crucible body, and the excess gas that does not participate in the reaction flowing into the graphite crucible will not directly flow out of the crucible due to the obstruction of the upper gas guide cover. After the obstruction, the excess reaction gas flow forms a reflux in the crucible and contacts with the material again to participate in the reaction. After the reaction is completed, remove the gas guide cover and pour the material out of the graphite crucible body.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A graphite crucible for gas-based reduction metallurgy, characterized in that: The invention comprises a graphite crucible main body. Both ends of the graphite crucible main body are provided with gas guide covers, and the gas guide covers are provided with dense sieve-like through holes.

2. The graphite crucible for gas-based reduction metallurgy according to claim 1, characterized in that: The gas guide cover is protruded toward the inside of the graphite crucible body, the protrusion is matched with the port of the graphite crucible body, the protrusion is connected with the gas guide cover, and dense sieve-like through holes are also arranged around the protrusion.

3. The graphite crucible for gas-based reduction metallurgy according to claim 2, characterized in that: The protrusion is in a cylindrical table structure.

4. The graphite crucible for gas-based reduction metallurgy according to claim 1, characterized in that: The graphite crucible body is a cylindrical structure with openings at both ends, and an accommodating space for loading materials is reserved between the gas guide cover and the graphite crucible body.

5. The graphite crucible for gas-based reduction metallurgy according to claim 2, characterized in that: The protrusion is also provided with external threads around it, the port of the graphite crucible body is provided with internal threads matching the external threads, and the protrusion is threadedly connected to the graphite crucible body.

6. The graphite crucible for gas-based reduction metallurgy according to claim 1, characterized in that: The diameter of the through hole is less than 10 mm.

7. A gas-based reduction metallurgy method, characterized in that: The graphite crucible for gas-based reduction metallurgy according to any one of claims 1 to 6 comprises the following steps: First, install the lower gas guide cover on the bottom of the graphite crucible body, so that the reaction gas is dispersed into the graphite crucible through the side through holes around the lower gas guide cover, load the material in the graphite crucible, fix the upper gas guide cover on the top of the graphite crucible body, and the excess gas that does not participate in the reaction flowing into the graphite crucible will not directly flow out of the crucible due to the obstruction of the upper gas guide cover. After the obstruction, the excess reaction gas flow forms a reflux in the crucible and contacts with the material again to participate in the reaction. After the reaction is completed, remove the gas guide cover and pour the material out of the graphite crucible body.

Images