A method for producing beryllium glass powder by water atomization

Abstract

The application relates to a method for producing beryllium glass powder by a water atomization method, which comprises the following steps: uniformly mixing beryl powder and calcite powder according to a mass ratio of 2:(1-1.1) to obtain a mixture; under vacuum or a protective atmosphere, performing induction smelting on the mixture to obtain a glass melt; wherein the temperature of the induction smelting is 1500-1700 DEG C, and the time is 30-120 min; taking the glass melt as raw material, performing powdering by a high-pressure water atomization method, cooling, drying, and obtaining beryllium glass powder; wherein when the high-pressure water atomization is performed, the glass melt flows down through the leakage eye of a tundish while being sprayed by a high-pressure water jet. The beryllium glass powder prepared by the method has excellent quality, can preferably meet the requirement of further extracting beryllium from the beryllium glass powder, the process flow of the method is short, the conversion rate of the furnace charge is high, and the preparation cost is reduced.

Description

Technical Field

[0001] This invention relates to a method for producing beryllium glass powder by water atomization, belonging to the field of beryllium smelting. Background Technology

[0002] Beryllium glass is the basic raw material for the production of beryllium and beryllium compounds. The production of beryllium glass powder is the initial step in the entire beryllium industry, while fine beryllium glass powder is the raw material for subsequent processes (see CN116002727A). Currently, the production of beryllium glass powder mainly involves the following three steps:

[0003] Step 1: Production of high-temperature beryllium glass melt: Beryllium ore reacts with calcite at a high temperature above 1480℃, and its original structure is destroyed to generate high-temperature beryllium glass melt.

[0004] Step 2: Quench the high-temperature molten liquid beryllium glass into water to break it down and obtain solid coarse beryllium glass.

[0005] Step 3: Mechanically ball-mill the coarse beryllium glass to obtain fine beryllium glass powder.

[0006] Each step of the production process is completed independently by different equipment and personnel, following a series of technological processes in an assembly line operation. In summary, the current beryllium glass fine powder production process has the following shortcomings: long production process, long production cycle, high cost, large footprint, high levels of dust, wastewater, and steam, and a dirty and unsanitary production environment. The electric arc furnace melting method for producing beryllium glass fine powder consumes over 2200 yuan per ton in electricity and labor costs.

[0007] Furthermore, in the first step mentioned above, the production method for high-temperature beryllium glass melt is typically an electric arc furnace heating method, using an electric arc as the heat source. Using an electric arc as a heat source presents the following problems: 1) Electric arc furnaces primarily use lumpy beryllium ore as raw material, making powdered beryllium ore unsuitable, leading to waste and increased production costs. 2) During the arcing process at the electrodes, fine powdery raw materials easily overflow from the electrode holes and furnace opening, causing material loss, polluting the environment, and posing a beryllium toxicity hazard, threatening the health of on-site employees. 3) Once the furnace lining is eroded, the outer shell is easily burned through, requiring a large amount of cold water to cool the outer shell during furnace startup, further increasing energy consumption; processing one ton of mixed material requires 2500 kWh of electricity. 4) Electric arc furnaces require frequent maintenance; cooling from high temperature to a suitable temperature takes a long time, and with the addition of dismantling the old furnace body and replacing it with a new one, the time can be as long as 5 days, affecting production rhythm, reducing production efficiency, and increasing production costs. 5) The center temperature can reach over 2000℃, while the material temperature is low and uneven in areas without arc, resulting in a low charge conversion rate of only about 96%. The actual temperature required for the reaction is approximately 1500℃. The temperature rise from 1500℃ to 2000℃ and the maintenance at that high temperature, while the furnace shell must be cooled by water, results in significant energy waste and increases production costs. Summary of the Invention

[0008] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for producing beryllium glass powder by water atomization, so as to simplify the preparation process of beryllium glass powder and achieve low-cost preparation of high-quality beryllium glass powder.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0010] A method for producing beryllium glass powder by water atomization includes the following steps:

[0011] S1. Mix beryl powder and calcite powder evenly at a mass ratio of 2:(1-1.1) to obtain a mixture;

[0012] S2. The mixture is induction melted under vacuum or protective atmosphere to obtain glass melt;

[0013] The induction melting temperature is 1500-1700℃, and the time is 30-120min;

[0014] S3. Using the glass melt as raw material, beryllium glass powder is obtained by high-pressure water atomization, cooling, and drying.

[0015] During high-pressure water atomization, the molten glass flows down through the leak in the tundish while being sprayed with high-pressure water jets.

[0016] Furthermore, in S1, the beryl powder has a particle size of -100 mesh; the calcite powder has a particle size of -100 mesh.

[0017] Furthermore, in S1, the mass ratio of beryl powder to calcite powder is 2:(1.02-1.08), preferably 2:(1.04-1.06).

[0018] Furthermore, the main component of the beryl powder is Be3Al2(SiO3)6, and the content of Be3Al2(SiO3)6 is ≥90wt%, preferably 92-98wt%.

[0019] Furthermore, the main component of the calcite powder is CaCO3, and the content of CaCO3 is ≥98wt%, preferably 98.5-99.5wt%.

[0020] Further, in S2, the mixture is placed in a graphite crucible and induction melting is performed.

[0021] Furthermore, in S2, the induction melting temperature is 1550-1650℃, and the time is 60-100min.

[0022] Furthermore, in S2, the protective atmosphere is a mixture of nitrogen and carbon dioxide.

[0023] Furthermore, in S3, the high-pressure water jet is generated by multiple cylindrical nozzles, which are evenly distributed circumferentially along the central axis of the leak. Each cylindrical nozzle is set obliquely downward, and the central axis of each cylindrical nozzle intersects the central axis of the leak at the same point.

[0024] Furthermore, the number of cylindrical nozzles is 12-20, preferably 14-18.

[0025] Furthermore, the diameter of the cylindrical nozzle is 1.2-1.5 mm, the length of the cylindrical nozzle is 2.5-3.5 mm, and the angle between the central axis of the cylindrical nozzle and the central axis of the drain hole is 38-40 degrees. The distance between the outlet of the cylindrical nozzle and the central axis of the drain hole is 95-105 mm.

[0026] Furthermore, the diameter of the leak is 15-25mm.

[0027] Furthermore, in S3, the unit pressure of the high-pressure water jet is 15-35 MPa, and the flow rate of the high-pressure water jet is 350-520 L / min.

[0028] Water atomization has been widely used in the preparation of metal powders. However, the properties of metals are completely different from those of glass, and the properties of molten metals are also completely different from those of molten glass. Therefore, the water atomization process for metal powders cannot be simply copied for glass powder atomization. Through repeated research, the applicant has discovered a suitable process for preparing beryllium glass powder using water atomization, which can achieve high-quality, low-cost preparation of beryllium glass powder and ensure a high charge conversion rate, thereby reducing the amount of beryllium wasted in subsequent leaching processes.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] (1) The beryllium glass powder prepared by the method of the present invention has excellent quality and high grade. The -200 mesh powder accounts for more than 85% of all powders (conventional processes generally only require more than 80%), the D50 particle size is about 26 μm, and the D90 particle size is about 67 μm, which can better meet the requirements for further extraction of beryllium from beryllium glass powder.

[0031] (2) The method of the present invention obtains the target beryllium glass powder by water atomization after obtaining the beryllium glass melt through melting, omitting the intermediate crude beryllium glass preparation step, which can effectively shorten the process flow, improve production efficiency, and reduce preparation costs. The electricity consumption and labor cost per ton does not exceed RMB 1,000.

[0032] (3) The method of the present invention has a high conversion rate of furnace charge, reaching more than 99.2%, with little material loss, and is green and environmentally friendly. Attached Figure Description

[0033] Figure 1 This is a diagram showing the structural positional relationship between a cylindrical nozzle and a drain hole according to the present invention.

[0034] Figure 2 This is a summary table of the relevant parameters and technical effects of Examples 1-18 and Comparative Examples 1-9.

[0035] Figure 3 This is a summary table of the relevant parameters and technical effects for comparison scales 10-18. Detailed Implementation

[0036] The present invention will be described in detail below with reference to embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0037] Examples 1-18, Comparative Examples 1-18

[0038] A method for producing beryllium glass powder by water atomization includes the following steps:

[0039] S1. Mix beryl powder (beryllium ore, Be3Al2(SiO3)6 content of 92wt%) and calcite powder (CaCO3 content of 98.5wt%) at a mass ratio of 2:(1-1.1) to obtain a mixture.

[0040] The beryl powder has a particle size of -100 mesh, and the calcite powder has a particle size of -100 mesh.

[0041] S2. The mixture is placed in a graphite crucible and induction melted under a protective atmosphere (a mixture of carbon dioxide and nitrogen) to obtain a glass melt.

[0042] The induction melting temperature T is 1500-1700℃, and the time t is 30-120min;

[0043] S3. Using the glass melt as raw material, beryllium glass powder is obtained by high-pressure water atomization, cooling, and drying.

[0044] During high-pressure water atomization, the molten glass flows down through the tundish drain while being sprayed with high-pressure water jets; the unit pressure P of the high-pressure water jet is 15-35MPa, and the flow rate Q of the high-pressure water jet is 350-520L / min.

[0045] See Figure 1The high-pressure water jet (columnar) is generated by multiple cylindrical nozzles 2 (N being 11-23 in number). These nozzles 2 are evenly distributed circumferentially along the central axis of the drain 1 (parallel to the vertical direction), with each nozzle 2 angled downwards. The central axis of each nozzle intersects the central axis of the drain 1 at the same point, and the distance between the nozzle outlet and the central axis of the drain 1 is 99 mm. The diameter D1 of the cylindrical nozzle is 1.2-1.5 mm, the length L is 2.5-3.5 mm, and the angle α between the central axis of the nozzle and the central axis of the drain is 38-40 degrees. The diameter D2 of the drain is 15-25 mm.

[0046] The specific values ​​of the relevant parameters in each embodiment and comparative example are as follows: Figure 2 and Figure 3 The data presented herein shall prevail.

[0047] Among them, the proportion of -200 mesh beryllium glass powder R1 refers to the proportion of -200 mesh beryllium glass powder in the total amount of beryllium glass powder obtained, which is specifically obtained by detection using a Malvern laser particle size analyzer;

[0048] D50 and D90 were obtained by Malvern laser particle size analyzer.

[0049] The charge conversion rate (R2) refers to the ratio of beryllium content in the leachate obtained after leaching beryllium glass powder using an acid leaching method to the beryllium content in the raw material (beryl). Specifically, the acid leaching method refers to the sulfuric acid method, in which beryllium glass powder is mixed with concentrated sulfuric acid (98 wt%) at a weight ratio of 1:2, reacted for 2 hours, and after solid-waste separation, the beryllium content in the leachate is measured.

[0050] The electricity and labor cost per ton (C) refers to the total cost of electricity and labor required to produce 1 ton of beryllium glass powder.

[0051] Combination Figure 2 and Figure 3 The results show that by using the method of this invention and controlling appropriate raw material ratios, melting parameters and water atomization parameters, the conversion rate of furnace charge can be effectively improved, high-quality beryllium glass powder can be obtained, and the total cost of electricity consumption per ton and labor can be controlled at a low level, which has good prospects for promotion and application.

[0052] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

Claims

1. A method for producing beryllium glass powder by water atomization, characterized in that, Includes the following steps: S1. Mix beryl powder and calcite powder evenly at a mass ratio of 2:(1-1.1) to obtain a mixture; S2. The mixture is induction melted under vacuum or protective atmosphere to obtain glass melt; The induction melting temperature is 1500-1700℃, and the time is 30-120min; S3. Using the glass melt as raw material, beryllium glass powder is obtained by high-pressure water atomization, cooling, and drying. In the process of high-pressure water atomization, the molten glass flows down through the tundish drain while being jetted with high-pressure water. In step S3, the high-pressure water jet is generated by multiple cylindrical nozzles, which are evenly distributed circumferentially along the central axis of the drain. Each cylindrical nozzle is set obliquely downward, and the central axis of each nozzle intersects the central axis of the drain at the same point. The number of cylindrical nozzles is 12-22. The diameter of each cylindrical nozzle is 1.2-1.5 mm, the length of each cylindrical nozzle is 2.5-3.5 mm, the angle between the central axis of the cylindrical nozzle and the central axis of the drain is 38-40 degrees, and the distance between the outlet of the cylindrical nozzle and the central axis of the drain is 95-105 mm. The diameter of the drain is 15-25 mm. In step S3, the unit pressure of the high-pressure water jet is 15-35 MPa, and the flow rate of the high-pressure water jet is 350-520 L / min.

2. The method according to claim 1, characterized in that, In S1, the beryl powder has a particle size of -100 mesh; the calcite powder has a particle size of -100 mesh.

3. The method according to claim 1, characterized in that, In S1, the mass ratio of beryl powder to calcite powder is 2:(1.02-1.08).

4. The method according to claim 3, characterized in that, In S1, the mass ratio of beryl powder to calcite powder is 2:(1.04-1.06).

5. The method according to claim 1, characterized in that, In step S2, the mixture is placed in a graphite crucible and induction melting is performed.

6. The method according to claim 1, characterized in that, In S2, the induction melting temperature is 1550-1650℃ and the time is 60-100min.

7. The method according to claim 1, characterized in that, The number of cylindrical nozzles is 12-20.

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