CN115401206B - A device and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder - Google Patents

Abstract

The invention is suitable for the technical field of high-purity metal material preparation, and provides equipment and a method for preparing high-purity spherical magnesium and/or high-purity magnesium powder, wherein the equipment comprises a vertical furnace body, a heating area and a condensing area; the periphery of the condensation area is sequentially provided with a first heat preservation device and a second heat preservation device from bottom to top, and the first heat preservation device and the second heat preservation device are detachably installed; the periphery of the condensation area is provided with a liquid cooling device; the condensing zone is also provided with a gas inlet and a gas outlet; the inner wall of the condensation area is provided with a mounting structure for mounting the collecting device. By controlling the heating temperature of the materials and the condensing condition of the condensing zone, the evaporated magnesium vapor is condensed into high-purity spherical magnesium and/or high-purity magnesium powder with different shapes and sizes on a collecting device of the condensing zone. The device of the invention is simple, can realize large-scale production, and can prepare high-purity spherical magnesium and high-purity magnesium powder simultaneously.

Description

A device and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder

Technical Field

The invention relates to the technical field of high-purity metal material preparation, and in particular to a device and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder.

Background technique

Magnesium metal is widely used in the fields of automobile, aerospace, rail transportation, electronic communication, national defense and military industry because of its advantages such as high specific strength and specific stiffness, easy processing and molding, good damping and shock absorption, and strong electromagnetic shielding ability. It is known as the "21st century green engineering material". It is known as the "revolutionary medical metal material" because of its good biocompatibility and biodegradability. In addition, magnesium is used in steel desulfurization and strategic metal reducing agent because of its active chemical properties. Spherical magnesium and magnesium powder have large specific surface area and strong surface activity. They can be used to manufacture chemical products, explosives, fireworks, etc. They are also efficient reducing agents, desulfurizers, and 3D printing raw materials. In addition, magnesium powder can also be used in high-tech fields such as advanced magnesium powder pigments in the automotive and building materials industries and conductive pastes for solar photovoltaic cell backplanes.

my country has abundant reserves of magnesium resources, and its primary magnesium production has ranked first in the world for many years. After decades of development, great progress has been made in the application of magnesium metal in alloy production, hydrogen storage materials, medical materials and other fields. However, the research on magnesium powder preparation started late and developed slowly in my country. At present, the main methods for producing magnesium powder are atomization, cutting, ball milling, etc. The above methods have defects such as complex equipment, high noise, unstable product size, low production efficiency, and low product purity. There are few reports on the preparation of spherical magnesium. Therefore, it is of great significance to develop a simple and efficient preparation technology for high-purity spherical magnesium and high-purity magnesium powder.

Patent 201710726429.2 proposes a method for preparing high-purity magnesium powder, which allows the raw materials to sublimate and condense in a tubular furnace at 700-1500°C (preferably 1000-1300°C), and can prepare high-purity magnesium powder with a purity of 99.9%, but this method has a small production scale and limited product purity. Patent 201310082862.9 proposes a pneumatic atomization production method for high-purity fine spherical metal magnesium powder, which uses argon atomization and nitrogen cooling to prepare spherical magnesium powder, but this method requires the use of nitrogen, argon and cooling and separation devices, and the equipment is expensive and the process is complicated.

Patent 202011059832.2 discloses a production device and process for spherical metallic magnesium powder. Spherical magnesium particles are prepared by cutting, but the particle size of the magnesium powder obtained by this method cannot be guaranteed, and the equipment is complex, noisy, and the product particle size is unstable.

Patent 202111623596.7 discloses a device and method for preparing ultrafine high-purity spherical magnesium powder. This method keeps a 120g magnesium ingot warm for 40 minutes, and prepares magnesium powder with a purity of 99.9% under the joint action of equipment such as an evaporation gasification furnace, a particle condenser, a cyclone dust collector, a gas filter and a gas cooler. The production scale is small and the product purity is low.

In summary, the existing technology has technical problems such as inability to achieve large-scale production, low product purity, complex equipment, and complex processes.

Summary of the invention

The present application provides an apparatus and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder, so as to solve at least one of the problems in the prior art of small-scale preparation of high-purity spherical magnesium and high-purity magnesium powder, low product purity, and complex process and equipment.

On the one hand, the present application provides an apparatus for preparing high-purity spherical magnesium and/or high-purity magnesium powder, comprising a vertical furnace body, a heating zone and a condensing zone, wherein the heating zone and the condensing zone are arranged in the vertical furnace body, and the heating zone is located below the condensing zone; a heating body is arranged at the periphery of the heating zone; a first heat-insulating device and a second heat-insulating device are arranged at the periphery of the condensing zone in sequence from bottom to top, and the first heat-insulating device and the second heat-insulating device are detachably installed; a liquid cooling device is also arranged at the periphery of the condensing zone; a gas inlet and a gas outlet are also provided in the condensing zone; and an installation structure for installing a collecting device is arranged on the inner wall of the condensing zone.

Furthermore, it also includes a filtering device, which is detachably arranged between the heating area and the condensing area.

Furthermore, it also includes a plurality of collecting devices, the width of which is greater than half of the diameter of the furnace body and smaller than the diameter of the furnace body, and the collecting devices are staggeredly arranged on the inner wall of the condensation zone.

Furthermore, the condensing device includes a cooling liquid inlet, a cooling liquid outlet and a cooling pipe, the cooling liquid outlet is arranged above the side wall surface of the vertical furnace body corresponding to the condensing zone, the cooling pipe is coiled on the outer wall surface of the heating zone and/or the condensing zone, and the cooling liquid inlet is arranged below the side wall surface of the vertical furnace body corresponding to the heating zone or the condensing zone.

Furthermore, it also includes a vacuum pump and a gas storage device, wherein the vacuum pump is connected to the gas outlet through a pipeline and a first control valve, and the gas storage device is connected to the gas inlet through a pipeline via a second control valve and a flow meter.

Furthermore, it also includes a control system, which includes a heating control system, a gas control system and a cooling circulation system; the heating control system is connected to the heating body and temperature sensors respectively arranged in the heating area and the condensing area; the gas control system is connected to the air pump, the first control valve, the second control valve and the flow meter; the cooling circulation system is connected to a liquid pump, and the liquid pump allows the coolant to circulate in the liquid cooling device.

Furthermore, it also includes a crucible, and the crucible is arranged in the heating zone.

On the other hand, the present application provides a method for preparing high-purity spherical magnesium and/or high-purity magnesium powder using the above-mentioned device for preparing high-purity spherical magnesium and/or high-purity magnesium powder, comprising the following steps:

S10. The crude magnesium or magnesium ingot is placed in a crucible, the crucible is placed in the heating zone of the crucible, a filtering device and a collecting device are sequentially installed above the crucible, and the vertical furnace is sealed;

S20. Turn on the vacuum pump and the first control valve to evacuate the furnace. When the vacuum degree in the furnace drops to a preset vacuum degree, start heating the heating zone. At the same time, open the second control valve and the coolant circulation system to keep the gas and coolant flowing; the gas is a gas that does not react with magnesium vapor;

Control the temperature of the heating zone to 650-1500°C, adjust the second control valve to adjust the gas flow rate to 1-500LPM, adjust the coolant flow rate to 1-100LPM, and control the temperature of the condensation zone to 100-700°C;

S30. When the crude magnesium or magnesium ingot is completely evaporated, the heating is stopped; when the temperature drops to room temperature, the gas control system and the coolant circulation system are turned off, and the collecting device is removed to obtain high-purity spherical magnesium and/or high-purity magnesium powder.

Further, the temperature of the heating zone is controlled to be 650-900°C, the second control valve is adjusted so that the gas flow rate is 200-500LPM, the coolant flow rate is adjusted to 50-100LPM, and the temperature of the condensation zone is controlled to be 100-400°C to prepare high-purity magnesium powder; the temperature of the heating zone is controlled to be 900-1500°C, the second control valve is adjusted so that the gas flow rate is 1-200LPM, the coolant flow rate is adjusted to 1-50LPM, and the temperature of the condensation zone is controlled to be 400-700°C to prepare high-purity spherical magnesium; the temperature of the heating zone is controlled to be 800-1300°C, the gas flow rate is 100-400LPM, the cooling water flow rate is 30-70LPM, and the condensate temperature is controlled to be 200-600°C (preferably 900-1200°C, the gas flow rate is 200-300LPM, and the cooling water flow rate is 40-60LPM) to simultaneously prepare high-purity spherical magnesium and high-purity magnesium powder.

Furthermore, when preparing high-purity magnesium powder, the first heat insulation device and the second heat insulation device are removed; when preparing high-purity spherical magnesium, the first heat insulation device and the second heat insulation device are installed; when preparing high-purity spherical magnesium and high-purity magnesium powder at the same time, the first heat insulation device is installed and the second heat insulation device is removed.

Compared with the prior art, the device and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder of the present application have at least the following beneficial effects:

(1) The equipment of the present application adopts a vertical structure, which effectively integrates raw material evaporation, metal vapor filtration and purification, metal vapor condensation, and product collection devices in the same equipment. Through the efficient coordination of the above devices, the raw material purification and product preparation processes are realized in the same equipment, solving the problems of complex existing equipment systems, high production costs, and low product purity.

(2) The equipment of the present application is provided with a detachable first heat preservation device and a second heat preservation device, which cooperate with the use of a liquid cooling device and cooling gas, can flexibly control the temperature in the condensation zone, effectively control the temperature distribution and temperature gradient in the equipment, and avoid the problem of equipment complexity and increased energy consumption caused by the two-stage heating and temperature control commonly used in conventional equipment. In addition, two products can be prepared in batches or simultaneously in the same set of equipment, and the high-purity spherical magnesium and high-purity magnesium powder obtained in the same batch have different particle sizes. After screening, products of different specifications can be obtained, realizing the production of diversified products with the same set of equipment.

(3) The method of the present application utilizes the different saturated vapor pressures of various elements in crude magnesium and magnesium ingots, the volatilization and condensation of magnesium vapor, molecular collisions, and nucleation and crystallization of metal vapor. Based on equipment design and condition control, the metal is purified by vacuum distillation and filtration devices, and different products are obtained by condensation condition control. The purity of the obtained product can reach 99.999%, which can meet the use requirements of different fields and avoid the problems of small preparation scale, low product purity, complex process and equipment in the existing method. The coolant and gas used in the process can be recycled, which meets the requirements of green and sustainable development of the metallurgical and material industries.

BRIEF DESCRIPTION OF THE DRAWINGS

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

1 is a schematic structural diagram of an apparatus for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to Example 1 of the present invention;

FIG. 2 is a scanning electron microscope image of high-purity spherical magnesium and high-purity magnesium powder prepared in an embodiment of the present invention.

In the figure, 1-control system, 2-vacuum pump, 3-vertical furnace body, 4-collecting device, 5-top cover, 6-second heat preservation device, 7-cooling liquid outlet, 8-first heat preservation device, 9-gas storage device, 10-flow meter, 11-raw material, 12-crucible, 13-heating body, 14-cooling liquid inlet, 15-filtering device.

Detailed ways

The following description provides many different embodiments or examples for implementing different features of the present invention. The components and arrangements described in the following specific examples are only used to simplify the present invention and are only used as examples, not to limit the present invention.

Example 1

A device for preparing high-purity spherical magnesium and/or high-purity magnesium powder, as shown in FIG1 , comprises a vertical furnace body 3, a heating zone and a condensing zone, wherein the heating zone and the condensing zone are arranged in the vertical furnace body 3, and the heating zone is located below the condensing zone;

A heating body 13 is arranged on the periphery of the heating zone; a first heat-insulating device 8 and a second heat-insulating device 6 are arranged on the periphery of the condensing zone in sequence from bottom to top, and the first heat-insulating device 8 and the second heat-insulating device 6 are detachable and installable; a liquid cooling device is also arranged on the periphery of the condensing zone; a gas inlet and a gas outlet are also provided in the condensing zone; an installation structure for installing a collecting device is arranged on the inner wall of the condensing zone.

The first heat preservation device and the second heat preservation device can be high temperature resistant and detachable heat preservation materials such as graphite felt or heat preservation cotton, which are directly coated on the periphery of the condensation zone; the first heat preservation device and/or the second heat preservation device are selectively set according to the different purposes of preparing high purity spherical magnesium or high purity magnesium powder. For example, when preparing high purity magnesium powder, it is necessary to control the lower temperature of the condensation zone. At this time, the first heat preservation device and the second heat preservation device are removed, and the circulating cooling effect of the coolant in the liquid cooling device is increased, and a larger inert gas flow rate is controlled, so that the temperature of the condensation zone is controlled at a relatively low 100-400°C; when preparing high purity spherical magnesium, the first heat preservation device and the second heat preservation device are installed at this time, and the smaller coolant flow rate and inert gas flow rate are controlled, so that the temperature of the condensation zone is controlled at a relatively high 400-700°C; when preparing high purity spherical magnesium and high purity magnesium powder at the same time, the first heat preservation device is installed at this time, and the second heat preservation device is removed, so that the temperature of the condensation zone is controlled at 200-600°C.

The liquid cooling device outside the condensation zone is used to allow the coolant to flow around the condensation zone. It is generally wound around the outer wall of the condensation zone in the form of a pipe. The winding method can be spiral winding or other winding methods. These are all conventional technologies in the field and will not be described in detail here. Those skilled in the art will understand that the coolant can be selected according to the situation, such as water or other types of coolant. Since these are all existing technologies, they will not be described in detail here.

The condensing device includes a cooling liquid inlet 14, a cooling liquid outlet 7 and a cooling pipe, wherein the cooling liquid outlet is arranged above the side wall surface of the vertical furnace body corresponding to the condensing zone, the cooling pipe is coiled on the outer wall surface of the heating zone and/or the condensing zone, and the cooling liquid inlet is arranged below the side wall surface of the vertical furnace body corresponding to the heating zone or the condensing zone. The cooling liquid includes but is not limited to cooling water, cooling oil and other cooling media that can cool the furnace body.

It is worth noting that the cooling pipe can be coiled only around the periphery of the condensation zone to cool only the condensation zone. At this time, the cooling liquid inlet is arranged below the side wall of the vertical furnace body corresponding to the condensation zone; at the same time, the cooling pipe can also be coiled around the periphery of the condensation zone and the heating zone at the same time. This arrangement can cool the condensation zone and the heating zone at the same time during the production process, that is, there is no need to set up an additional separate condensation device to cool the heating zone, and it is convenient for cooling the entire device after the experiment is completed. At this time, the cooling liquid inlet can be arranged below the side wall of the vertical furnace body corresponding to the heating zone.

During the experiment, the liquid cooling device is connected to a liquid pump, and the coolant is pumped into the liquid cooling device through the liquid pump, so that the coolant flows on the outer wall of the condensation area, taking away the heat inside the condensation area. In order to facilitate the control of the flow rate of the coolant, corresponding valves and flow meters are also provided.

The gas inlet and gas outlet of the condensation zone are preferably arranged in such a way that the gas inlet is arranged below the side wall surface of the vertical furnace body corresponding to the condensation zone, and the gas outlet is arranged above the other side wall surface of the vertical furnace body corresponding to the condensation zone, thereby allowing the gas to pass through the entire condensation zone from bottom to top, achieving the best effect, ensuring that the volatilized magnesium vapor can fully contact with the charged low-temperature gas, and allowing the magnesium vapor to be carried to the collection device in the condensation zone under the synergistic effect of the charged airflow and the suction force of the vacuum pump.

During the experiment, a vacuum pump 2 and a gas storage device 9 are also provided. The vacuum pump 2 is connected to the gas outlet through a pipeline and a first control valve, and the gas storage device 9 is connected to the gas inlet through a pipeline via a second control valve and a flowmeter 10. The speed and flow of the gas extraction are controlled by the first control valve, and the speed and flow of the gas filled into the condensation zone are controlled by the second control valve. The gas filled into the condensation zone is a gas that does not react with magnesium, including but not limited to inert gases such as helium, neon, argon, krypton, xenon, and radon.

The device also includes a filtering device, which is detachably arranged between the heating zone and the condensing zone. The filtering device can be a porous material made of graphite, ceramic or metal, and can effectively filter ash and large particle impurities in the raw material to improve the purity of the prepared high-purity spherical magnesium and/or high-purity magnesium powder.

The invention also includes a plurality of collecting devices 4, the width of which is greater than half of the furnace body diameter and less than the furnace body diameter, and which are staggeredly arranged on the inner wall of the condensation zone, and the collecting devices can be round graphite or stainless steel trays. The collecting devices are used to collect the prepared high-purity spherical magnesium and/or high-purity magnesium powder.

The crucible 12 is also included, and the crucible is arranged in the heating zone. Those skilled in the art can understand that the crucible is used to hold the raw material 11.

It also includes a control system 1, which includes a heating control system, a gas control system and a cooling circulation system; the heating control system is connected to the heating body and the temperature sensors respectively arranged in the heating zone and the condensing zone; the gas control system is connected to the vacuum pump, the first control valve, the second control valve and the flow meter; the cooling circulation system is connected to a liquid pump, and the liquid pump allows the coolant to circulate in the liquid cooling device. The heating control system can also include temperature measuring thermocouples, which are respectively arranged in the heating zone and the condensing zone, for collecting the temperature of the heating zone and the condensing zone, and controlling the heating of the heating body according to the set temperature range; and adjusting the cooling circulation system and the gas control system according to the measured temperature.

The device further comprises a top cover 5. Those skilled in the art will appreciate that the top cover 5 has a function similar to a furnace door. Opening or closing the top cover 5 can open or close the internal space of the furnace body for placing or removing materials, etc.

Example 2

A method for preparing high-purity spherical magnesium and/or high-purity magnesium powder using an apparatus for preparing high-purity spherical magnesium and/or high-purity magnesium powder as in Example 1, comprising the following steps:

S10. Place crude magnesium or magnesium ingot into a crucible, place the crucible in the heating zone, sequentially install a filtering device and a collecting device above the crucible, and seal the vertical furnace;

S20. Turn on the vacuum pump and the first control valve to evacuate the furnace. When the vacuum degree in the furnace drops to a preset vacuum degree, start heating the heating zone. At the same time, open the second control valve and the coolant circulation system to fill the condensation zone with inert gas.

Control the temperature of the heating zone to 650-1500°C, adjust the second control valve to control the gas flow to 1-500LPM; adjust the coolant circulation system so that the coolant flow is 1-100LPM, control the temperature of the condensation zone to 100-700°C, and set the heating zone temperature and the condensation zone temperature, as well as the gas and coolant flow rates according to the different products to be prepared. For example, the temperature of the heating zone is controlled to be 650-900°C, the second control valve is adjusted so that the gas flow rate is 200-500LPM, the coolant flow rate is adjusted to 50-100LPM, and the temperature of the condensation zone is controlled to be 100-400°C to prepare high-purity magnesium powder; the temperature of the heating zone is controlled to be 900-1500°C, the second control valve is adjusted so that the gas flow rate is 1-200LPM, the coolant flow rate is adjusted to 1-50LPM, and the temperature of the condensation zone is controlled to be 400-700°C to prepare high-purity spherical magnesium; the temperature of the heating zone is controlled to be 800-1300°C, the gas flow rate is 100-400LPM, the cooling water flow rate is 30-70LPM, and the condensate temperature is controlled to be 200-600°C (preferably 900-1200°C, the gas flow rate is 200-300LPM, and the cooling water flow rate is 40-60LPM) to simultaneously prepare high-purity spherical magnesium and high-purity magnesium powder.

S30. When the crude magnesium or magnesium ingot is completely evaporated, the heating is stopped; when the temperature drops to room temperature, the gas circulation system and the coolant circulation system are closed, and the collecting device is removed to obtain high-purity spherical magnesium and/or high-purity magnesium powder.

The principle of the device and preparation method of the present application is: using the principles of saturated vapor pressure, evaporation and condensation, molecular collision, nucleation and crystallization, etc., using crude magnesium or magnesium ingot as raw material, controlling the appropriate temperature to evaporate magnesium, and leaving impurities with low saturated vapor pressure in the residue. The evaporated magnesium vapor is purified again through a filter device, and the purified magnesium vapor collides with the charged gas molecules to different degrees to lose heat, and is carried into the condensation zone by the air flow. Through the dual cooling means of combining furnace water cooling and furnace air cooling, as well as the flexible setting of the condensation zone insulation device, the adjustment of the condensation water and gas flow, the magnesium vapor nucleation and crystallization process is controlled, so that the magnesium vapor is condensed into high-purity spherical magnesium or high-purity magnesium powder.

Specifically, if high-purity magnesium powder is prepared, a relatively low heating temperature is controlled to prevent a large amount of magnesium vapor from volatilizing at the same time and agglomerating and growing in the condensation zone, preferably 650-900°C, and a relatively large gas flow rate and cooling water flow rate are controlled, preferably 200-500LPM gas flow rate and 50-100LPM cooling water flow rate. During the heating process, the raw material slowly volatilizes, and the magnesium vapor purified by the filtering device fully collides with the charged low-temperature gas molecules and loses a large amount of heat, and enters the condensation zone under the combined action of the charged air flow and the vacuum pump suction force. Since no insulation device is placed outside the condensation zone and the combined action of the charged gas and liquid cooling can ensure that the temperature of the condensation zone is between 100-400°C, at which time the magnesium vapor is cooled into solid particles before growing up after nucleation, and the high-purity magnesium powders of different particle sizes collected on the collecting devices of each layer can be sieved to obtain high-purity magnesium powder products of different specifications.

If high-purity spherical magnesium is prepared, a relatively high heating temperature is controlled to ensure that sufficient magnesium vapor is agglomerated and grown in the condensation zone, preferably 900-1500°C, and a relatively small gas flow rate and cooling water flow rate are controlled, preferably 1-200LPM gas flow rate and 1-50LPM cooling water flow rate. During the heating process, the raw material volatilizes rapidly, and the magnesium vapor purified by the filtering device collides with the slowly charged low-temperature gas and loses part of the heat, and enters the condensation zone under the combined action of the charged air flow and the suction force of the vacuum pump. Due to the installation of thermal insulation materials and the control of relatively small air flow and cooling water flow rates, the temperature of the condensation zone can be guaranteed to be between 400-700°C, and the magnesium vapor is slowly cooled to form spherical magnesium under the action of surface tension. Spherical magnesium particles of different particle sizes collected by collecting devices at different positions can be obtained through screening to obtain high-purity spherical magnesium products of different specifications.

If high-purity spherical magnesium and high-purity magnesium powder are prepared at the same time, the production conditions are controlled appropriately, the temperature of the heating zone is controlled to be 800-1300°C, the gas flow rate is 100-400LPM, the cooling water flow rate is 30-70LPM, and the condensate temperature is controlled to be 200-600°C (preferably 900-1200°C, the gas flow rate is 200-300LPM, and the cooling water flow rate is 40-60LPM). The magnesium vapor volatilized during the heating process collides with the gas molecules and is carried by the airflow into the condensation zone. The condensation zone with an insulation layer installed below has a higher temperature, so the magnesium vapor is slowly cooled to generate high-purity spherical magnesium. The magnesium vapor in the condensation zone without an insulation layer installed above is rapidly condensed and cooled into a solid state before it grows up to obtain high-purity magnesium powder. That is, high-purity spherical magnesium and high-purity magnesium powder can be prepared at the same time.

In the above process, the gas and cooling water are collected and recycled. According to the test, the purity of the obtained high-purity spherical magnesium and high-purity magnesium powder can reach 99.999%.

Example 3

(1) Loading

Put 5 kg of crude magnesium into a crucible, place the crucible in the heating zone, and place a filter, a condensate collection device, and a top cover on the crucible in sequence. After the installation is completed, close the furnace cover and seal the equipment.

(2) Air extraction

After checking that the equipment is normal and installed correctly, set the temperature of the heating zone to 700℃ and keep it warm for 120 minutes, turn on the vacuum pump and keep it running.

(3) Preparation of high-purity magnesium powder

Run the heating program, control the gas flow rate to 400LPM, and the cooling water flow rate to 80LPM. During the heating process, the raw materials evaporate slowly, and the magnesium vapor purified by the filter device collides with the charged low-temperature gas molecules and loses a lot of heat. It enters the condensation zone under the joint action of the charged air flow and the vacuum pump. Since there is no insulation device in the condensation zone, and the large flow of charged gas and water cooling, the temperature of the condensation zone is 200℃. The magnesium vapor does not nucleate and grow on the collection device, and directly transforms from the gas phase to the solid phase to obtain high-purity magnesium powder. The products on each collection device are screened to obtain products of different specifications. The cooling water and charged gas are collected and recycled.

Example 4

(1) Loading

Put 5kg magnesium ingot into the crucible, place the crucible in the heating zone, place the filter, condensate collection device, and top cover on the crucible in sequence, and place the first and second insulation devices around the condensate collection device. After the installation is completed, close the furnace cover and seal the equipment.

(2) Air extraction

After checking that the equipment is normal and installed correctly, set the temperature of the heating zone to 1200℃ and keep it warm for 60 minutes, turn on the vacuum pump and keep it running.

(3) Preparation of high-purity spherical magnesium

Run the heating program, control the gas flow rate to 100LPM, and the cooling water flow rate to 30LPM. During the heating process, the raw materials evaporate rapidly, and the magnesium vapor purified by the filter device collides with the charged low-temperature gas molecules and loses some heat, and enters the condensation zone under the combined action of the charged air flow and the vacuum pump. Since the condensation zone is equipped with a heat preservation device, and the flow rate of the charged gas and cooling water is small, the temperature of the condensation zone is 650℃, so the magnesium vapor will not be cooled immediately after entering the condensation zone, and condenses into liquid on the collection device and nucleates and grows to obtain high-purity spherical magnesium. The products on each collection device are screened to obtain products of different specifications, and the cooling water and charged gas are collected and recycled.

Example 5

(1) Loading

Put 5kg magnesium ingot into the crucible, place the crucible in the heating zone, place the filter, condensate collection device, and top cover on the crucible in sequence, and place the first insulation device outside the condensation zone. After the installation is completed, close the furnace cover and seal the equipment.

(2) Air extraction

After checking that the equipment is normal and installed correctly, set the temperature of the heating zone to 850℃ and keep it warm for 90 minutes, turn on the vacuum pump and keep it running.

(3) Preparation of high-purity spherical magnesium and high-purity magnesium powder

Run the heating program, control the gas flow rate to 200LPM, and the cooling water flow rate to 50LPM. When the raw material volatilizes, the magnesium vapor enters the condensation zone through the filtering device. The principle is the same as the above embodiment. Since the temperature gradient between the lower condensation zone and the heating zone is small, the magnesium vapor slowly cools and grows to form spherical magnesium, while the temperature gradient between the upper condensation zone and the heating zone is large, and the magnesium vapor condenses into magnesium powder before it grows. The products on each collecting device are screened to obtain non-pass products, and the cooling water and the charging gas are collected and recycled.

The impurity content and purity of the high-purity spherical magnesium and high-purity magnesium powder prepared by the preparation device and method of the present application are shown in Table 1, and the scanning electron microscope image is shown in Figure 2.

Table 1 Impurity content and purity of high-purity spherical magnesium and high-purity magnesium powder (ppm)

It can be seen that the impurity content of the high-purity spherical magnesium and high-purity magnesium powder prepared in this application is less than 5ppm, and the product purity obtained by subtraction is greater than 5N. The obtained high-purity spherical magnesium has good sphericity, and the obtained high-purity magnesium powder has a smooth surface and distinct particles. The two products have high purity and large specific surface area. After screening, spherical magnesium and magnesium powder products of different specifications can be obtained, which can meet the use requirements of reducing agents, desulfurizers, chemical products, 3D printing and other fields.

It is worth noting that the device and method for preparing high-purity spherical magnesium and/or high-purity magnesium powder involved in the embodiments of the present application can be used for experimental research devices and methods, and can also be used for normal production as a device and method for producing high-purity spherical magnesium and/or high-purity magnesium powder.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. An apparatus for preparing high-purity spherical magnesium and/or high-purity magnesium powder, characterized in that it comprises a vertical furnace body, a heating zone and a condensing zone, wherein the heating zone and the condensing zone are arranged in the vertical furnace body, and the heating zone is located below the condensing zone; A heating body is arranged at the periphery of the heating zone; A first heat preservation device and a second heat preservation device are sequentially arranged on the periphery of the condensation zone from bottom to top, and the first heat preservation device and the second heat preservation device are detachable and installable; A liquid cooling device is also provided at the periphery of the condensation zone; The condensation zone is also provided with a gas inlet and a gas outlet; The inner wall of the condensation zone is provided with a mounting structure for mounting a collection device; The first heat-insulating device and the second heat-insulating device are heat-insulating materials resistant to high temperatures, and are directly coated on the periphery of the condensation zone; When preparing high-purity magnesium powder, the first heat preservation device and the second heat preservation device are removed; when preparing high-purity spherical magnesium, the first heat preservation device and the second heat preservation device are installed; when preparing high-purity spherical magnesium and high-purity magnesium powder at the same time, the first heat preservation device is installed and the second heat preservation device is removed; It also includes a plurality of collecting devices, the width of which is greater than half of the furnace body diameter and less than the furnace body diameter, and which are staggeredly arranged on the inner wall of the condensation zone; The gas inlet is arranged below the side wall surface of the condensation zone corresponding to the vertical furnace body, and the gas outlet is arranged above the other side wall surface of the condensation zone corresponding to the vertical furnace body. 2. The device for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to claim 1 is characterized in that it also includes a filtering device, which is detachably arranged between the heating zone and the condensation zone. 3. An apparatus for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to claim 2, characterized in that the liquid cooling device comprises a coolant inlet, a coolant outlet and a cooling pipe, the coolant outlet is arranged above the side wall surface of the vertical furnace body corresponding to the condensing zone, the cooling pipe is coiled on the outer wall surface of the heating zone and/or the condensing zone, and the coolant inlet is arranged below the side wall surface of the vertical furnace body corresponding to the heating zone or the condensing zone. 4. The device for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to claim 3 is characterized in that it also includes a vacuum pump and a gas storage device, wherein the vacuum pump is connected to the gas outlet through a pipeline and a first control valve, and the gas storage device is connected to the gas inlet through a pipeline via a second control valve and a flowmeter. 5. The device for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to claim 4, characterized in that it also includes a control system, the control system includes a heating control system, a gas control system and a cooling circulation system; The heating control system is connected to the heating body and temperature sensors respectively arranged in the heating area and the condensing area; The gas control system is connected to the vacuum pump, the first control valve, the second control valve and the flow meter; The cooling circulation system is connected to a liquid pump, and the liquid pump allows the coolant to circulate in the liquid cooling device. 6. The device for preparing high-purity spherical magnesium and/or high-purity magnesium powder according to claim 5, characterized in that it also includes a crucible, and the crucible is arranged in the heating zone. 7. A method for preparing high-purity spherical magnesium and/or high-purity magnesium powder using the device for preparing high-purity spherical magnesium and/or high-purity magnesium powder as claimed in claim 6, characterized in that it comprises the following steps: S10. Place crude magnesium or magnesium ingot into a crucible, place the crucible in the heating zone, sequentially install a filtering device and a collecting device above the crucible, and seal the vertical furnace; S20. Turn on the vacuum pump and the first control valve to evacuate the furnace. When the vacuum degree in the furnace drops to a preset vacuum degree, start heating the heating zone. At the same time, open the second control valve and the cooling circulation system to keep the gas and coolant flowing; the gas is a gas that does not react with magnesium vapor, and the coolant is a water or oil cooling medium; Control the temperature of the heating zone to 650-1500°C, adjust the second control valve so that the gas flow rate is 1-500LPM, adjust the coolant flow rate to 1-100LPM, and control the temperature of the condensation zone to 100-700°C; S30. When the crude magnesium or magnesium ingot is completely evaporated, the heating is stopped; when the temperature drops to room temperature, the gas control system and the cooling circulation system are turned off, and the collecting device is removed to obtain high-purity spherical magnesium and/or high-purity magnesium powder. 8. The method according to claim 7 is characterized in that the temperature of the heating zone is controlled to be 650-900°C, the second control valve is adjusted so that the gas flow rate is 200-500LPM, the coolant flow rate is adjusted to 50-100LPM, and the temperature of the condensation zone is controlled to be 100-400°C to prepare high-purity magnesium powder; the temperature of the heating zone is controlled to be 900-1500°C, the second control valve is adjusted so that the gas flow rate is 1-200LPM, the coolant flow rate is adjusted to 1-50LPM, and the temperature of the condensation zone is controlled to be 400-700°C to prepare high-purity spherical magnesium; the temperature of the heating zone is controlled to be 800-1300°C, the gas flow rate is 100-400LPM, the cooling water flow rate is 30-70LPM, and the temperature of the condensation zone is controlled to be 200-600°C to simultaneously prepare high-purity spherical magnesium and high-purity magnesium powder.