Fluidized bed carbonyl method powder surface modification production device and use method thereof

Abstract

The invention provides a fluidized bed carbonyl method powder surface modification production device and a use method thereof, belongs to the technical field of powder metallurgy and atomic vapor deposition, and solves the problem of lack of a stable and efficient fluidized bed carbonyl method powder surface modification production device in the prior art. An electromagnetic heater is arranged on the fluidized bed reactor, a fluidized bed hood is arranged at the bottom of the fluidized bed reactor, the fluidized bed reactor is sequentially connected with a cyclone separator and a dust collector, the dust collector is connected with the fluidized bed reactor, the cyclone separator and the dust collector are respectively connected with a passivation bin, and the passivation bin is connected with multistage linear screening equipment. According to the method, a chemical fluidized bed technology and a material chemical vapor deposition preparation technology are combined, the characteristics of high purity, low thermal dissociation temperature and the like of a carbonyl metal intermediate compound are utilized, carbonyl nickel liquid is used as a raw material, and atomic vapor deposition coating of high-purity nickel metal atoms is carried out.

Description

Technical Field

[0001] This invention belongs to the fields of powder metallurgy and atomic vapor deposition technology, specifically relating to a fluidized bed carbonyl method powder surface modification production device and its usage method. Background Technology

[0002] Metal-clad composite materials are a new type of composite functional materials with a core-shell structure. They not only retain the main characteristics of the metal coating and the coated particles, but also exhibit excellent comprehensive properties resulting from the interaction of the components through the composite effect. They can change their optical, magnetic, electrical, catalytic, hydrophilic, hydrophobic and sintering properties, and improve their corrosion resistance, durability, service life and thermal, mechanical and chemical stability. They have applications in many fields such as metallurgy, machinery and aerospace.

[0003] Fluidized bed chemical vapor deposition (FCVD) is a cross-coupled technology combining fluidized bed chemical engineering and chemical vapor deposition (CVD) for materials science. It leverages the advantages of fluidized bed deposition (high throughput, rapid heat transfer, and uniform temperature) and CVD deposition (wide temperature range and abundant products), making it crucial for applications in nuclear fuel preparation and powder surface modification. Thermal decomposition metal atom deposition using carbonyl nickel as a raw material offers advantages such as a short process, high purity, and no harmful exhaust gas generation. Utilizing the high purity, low thermal dissociation temperature, and diverse dissociation products of carbonyl metal intermediates, research on novel carbonyl composite materials is currently a hot topic in materials research, with broad application prospects in aerospace, electronics, energy, and chemical engineering.

[0004] Currently, the main carbonyl composite materials being researched include: carbonyl metal (or metal compound) composite powders, carbonyl metal coated materials, carbonyl metal thin film materials, and carbonyl metal functionally graded materials. However, a stable and efficient fluidized bed carbonyl powder surface modification production device is lacking. Summary of the Invention

[0005] The purpose of this invention is to provide a fluidized bed carbonyl powder surface modification production device and its usage method based on using carbonyl nickel liquid as raw material and a fluidized bed reactor as the main reaction equipment, so as to solve the problem of the lack of a stable and efficient fluidized bed carbonyl powder surface modification production device.

[0006] The technical solution of the present invention is: a fluidized bed carbonylation powder surface modification production device, comprising a feeding hopper, a fluidized bed reactor connected to the feeding hopper, an electromagnetic heater provided on the fluidized bed reactor, a fluidized bed air cap provided at the bottom of the fluidized bed reactor, a cyclone separator and a dust collector connected in sequence to the fluidized bed reactor, the dust collector being back connected to the fluidized bed reactor, the cyclone separator and the dust collector being respectively connected to a passivation chamber, and the passivation chamber being connected to a multi-stage linear screening device. As a further improvement of the present invention, the fluidized bed reactor is connected to a heater, and the heater is connected to a flow meter.

[0007] As a further improvement of the present invention, an observation port is provided at the top of the fluidized bed reactor.

[0008] As a further improvement of the present invention, a differential pressure gauge is provided on the fluidized bed reactor.

[0009] A method of using a fluidized bed carbonyl process powder surface modification production apparatus includes the following steps: Step 1: The coated material in the feeding hopper enters the fluidized bed reactor from the bottom and middle by its own weight. Nitrogen and gaseous nickel carbonyl are introduced into the fluidized bed reactor respectively. Step 2: After the atomic vapor deposition chemical reaction in the fluidized bed reactor is completed, the coated material is purged with nitrogen to a cyclone separator and pulse dust collector for collection, and then the material is transported to a passivation chamber where nitrogen is used to replace, detoxify, and cool the product. Step 3: The product released from the passivation chamber contains some unqualified products. The powder that is not fully coated and the powder with excessive coating are separated by a multi-stage linear sieving device, and finally qualified products are collected.

[0010] The beneficial effects of this invention are as follows: This invention utilizes a fluidized bed with nozzles at the bottom, employing a constant flow of CO gas to fluidize the material to be modified, keeping the raw material in a fluidized state. During the vapor deposition surface modification process, the fluidized material remains in suspension, ensuring the uniformity of metal atom deposition on the powder surface. The carbonyl nickel vapor-deposited powder is then separated by a cyclone separator, achieving a separation efficiency of 70-80%. Part of the exhaust gas is processed by a metal filter pulse dust collector to recover the remaining powder, resulting in an overall system metal recovery rate exceeding 90%. The composite powder material from the carbonyl nickel thermal decomposition vapor deposition is then purged by a large volume of gas at the bottom of the fluidized bed reactor and transported to a passivation chamber for cold nitrogen sterilization and replacement. The sterilized powder is then sieved through a multi-stage sieve, with incompletely coated powder and excessively coated powder undergoing further sieving. The properly coated composite powder is then released into packaging containers for sampling and analysis.

[0011] This invention combines chemical fluidized bed technology and materials chemical vapor deposition (CVD) technology, utilizing the high purity and low thermal dissociation temperature of carbonyl metal intermediate compounds, and using carbonyl nickel liquid as raw material to perform atomic vapor deposition coating of high-purity nickel metal atoms. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the device structure of the present invention.

[0013] In the diagram: 1-Feeding bin; 2-Fluidized bed reactor; 3-Heater; 4-Cyclone separator; 5-Dust collector; 6-Passivation bin; 7-Multi-stage linear screening equipment; 8-Observation port; 9-Fluidized bed air cap; 10-Flow meter; 11-Electromagnetic heater; 12-Differential pressure gauge. Detailed Implementation

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] Example 1 like Figure 1 As shown, a fluidized bed carbonylation powder surface modification production device includes a feeding hopper 1, which is connected to a fluidized bed reactor 2. The fluidized bed reactor 2 is equipped with an electromagnetic heater 11 and a fluidized bed air cap 9 at the bottom. The fluidized bed reactor 2 is sequentially connected to a cyclone separator 4 and a dust collector 5. The dust collector 5 is reconnected to the fluidized bed reactor 2. The cyclone separator 4 and the dust collector 5 are respectively connected to a passivation chamber 6. The passivation chamber 6 is connected to a multi-stage linear screening device 7.

[0016] The feeding hopper 1 is a powder feeding device designed to add the coated material into the fluidized bed reactor 2 by its own weight. The material enters the fluidized bed reactor 2 from the bottom and middle, respectively, ensuring uniform vapor deposition coating of the material above and below the bed. The material is heated using an electric heater 3 connected to the fluidized bed reactor 2 and an electromagnetic heater 11 installed on the wall of the reactor 2, further ensuring uniform heating of the powder and allowing for controllable temperature adjustment.

[0017] A gas inlet pipeline connected to an electric heater 3 and a flow meter 10 is installed at the bottom of the fluidized bed reactor 2. This is designed to stably control and regulate nitrogen or CO gas, thereby controlling the fluidization state of the material being coated within the reactor. A gas-distributing umbrella-shaped fluidized bed vent 9 is installed at the bottom of the reactor to increase the uniformity of the sulfur gas distribution, ensuring a uniform distribution of the gas entering the reactor and reducing channeling. A high-temperature resistant transparent glass observation port 8 is installed at the top of the reactor, allowing real-time observation of the fluidization state of the material inside. The flow meter 10 is used to adjust the flow rate of nitrogen or CO gas to regulate the fluidization state of the material. Differential pressure gauges 12 are installed at the top, middle, and bottom of the reactor to adjust the fluidization state of the material through pressure difference changes.

[0018] The top exhaust outlet of the fluidized bed reactor 2 is connected to a cyclone separator 4, which can effectively separate and collect the product with a separation efficiency of 70-80%.

[0019] The exhaust outlet of the cyclone separator 4 is connected to the pulse dust collector 5, which can recover the material to the passivation chamber 6 through gas backflushing. The purpose is to collect products that are not fully coated or do not meet the particle size requirements, with a recovery rate of over 90%, and return them to the fluidized bed reactor 2 to continue participating in the thermal decomposition atomic vapor deposition reaction until the coating requirements are fully met.

[0020] After the atomic vapor deposition chemical reaction in the fluidized bed reactor 2 is completed, the coated material is purged with nitrogen and collected by the cyclone separator 4 and pulse dust collector 5. The dust collector 5 is connected to the external exhaust purification system and the material is transported to the passivation chamber 6. Nitrogen is used to replace, detoxify and cool the product, and to purge and replace the trace amounts of toxic and harmful gases carried on the surface of the powder.

[0021] The product discharged from the passivation chamber 6 contains some unqualified products. The multi-stage linear screening equipment 7 can screen and remove powder materials that are over- or under-coated. The product is recovered from the secondary screening outlet. Then, the powder that is not fully coated and the powder with excessive coating degree are separated by multi-stage screening, and finally qualified products are collected.

[0022] This invention fluidizes coated powder with a reasonably designed bed height within a fluidized bed reactor 2 by stably controlling the flow rate of the fluidizing gas and the pressure difference in the reactor. Novel heating methods such as electric heating and electromagnetic heating are used to heat the core material of the shell-core structure inside the fluidized bed reactor 2 to the thermal decomposition temperature of nickel carbonyl. By stably introducing nickel carbonyl gas, which is vaporized by heating hot water, into the fluidized bed reactor 2, low-temperature thermal decomposition atoms are deposited on the surface of the coated powder in a fluidized suspension state, and metallic nickel atoms are uniformly deposited on the surface of the coated powder.

[0023] This invention controls the powder coating amount by controlling the thermal decomposition atomic vapor deposition time. Simultaneously, during the coating process, incompletely coated powder carried out by the continuously flowing fluidizing gas is forcefully separated by a cyclone separator 4. The separated powder is then reintroduced into the fluidized bed reactor 2 for further coating until complete coating is achieved.

[0024] After the atomic vapor deposition coating reaction is completed in the fluidized bed reactor 2, the composite powder material is sent to the pulse dust collector 4 for collection by airflow. After collection, the composite powder in the pulse dust collector 4 is released into the passivation chamber 6, and the composite powder material is cooled, detoxified and replaced by inert nitrogen.

[0025] After the replacement is completed, the ultrafine powder that is not fully coated and the powder with excessive coating degree are screened and impurities are removed using a multi-stage linear sieving device 7. The products designed by the composite coating process are collected for testing and packaging.

Claims

1. A fluidized bed carbonylation process powder surface modification production apparatus, characterized in that: The device includes a feeding bin (1), which is connected to a fluidized bed reactor (2). The fluidized bed reactor (2) is equipped with an electromagnetic heater (11) and a fluidized bed air cap (9) at the bottom. The fluidized bed reactor (2) is connected in sequence to a cyclone separator (4) and a dust collector (5). The dust collector (5) is connected back to the fluidized bed reactor (2). The cyclone separator (4) and the dust collector (5) are respectively connected to a passivation chamber (6). The passivation chamber (6) is connected to a multi-stage linear screening device (7).

2. The fluidized bed carbonylation powder surface modification production apparatus according to claim 1, characterized in that: The fluidized bed reactor (2) is connected to a heater (3), and the heater (3) is connected to a flow meter (10).

3. The fluidized bed carbonylation powder surface modification production apparatus according to claim 2, characterized in that: The fluidized bed reactor (2) is provided with an observation port (8) at the top.

4. The fluidized bed carbonylation powder surface modification production apparatus according to claim 3, characterized in that: The fluidized bed reactor (2) is equipped with a differential pressure gauge (12).

5. The method of using the fluidized bed carbonylation powder surface modification production device according to claim 4, characterized in that: Includes the following steps: Step 1: The material covered in the feeding bin (1) enters the fluidized bed reactor (2) from the bottom and middle by its own weight. Nitrogen and gaseous carbonyl nickel are introduced into the fluidized bed reactor (2) respectively. Step 2: After the atomic vapor deposition chemical reaction in the fluidized bed reactor (2) is completed, the coated material is purged with nitrogen to the cyclone separator (4) and dust collector (5) for collection, and the material is transported to the passivation chamber (6) for nitrogen to replace, detoxify and cool the product. Step 3: The product released from the passivation chamber (6) contains some unqualified products. The powder that is not fully coated and the powder with excessive coating are separated by multi-stage linear screening equipment (7) and finally qualified products are collected.

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