Organosilicon monomer synthesis aggregate returning system

Abstract

The utility model discloses an organic silicon monomer synthesis aggregate return system which is characterized in that the top of a fluidized bed is connected with a first-stage cyclone separator through a pipeline, the first-stage cyclone separator is connected with a first-stage cyclone separator receiving hopper through a pipeline, and the first-stage cyclone separator receiving hopper is respectively connected with a fine powder tank A and a fine powder tank B through pipelines; and the fine powder tank A and the fine powder tank B are respectively connected with a bottom inlet of the fluidized bed through pipelines. A gas phase outlet of the first-stage cyclone separator is connected with an inlet of a second-stage cyclone separator, the second-stage cyclone separator is connected with a second-stage cyclone receiving hopper through a pipeline, the second-stage cyclone receiving hopper is connected with a discharging hopper, a gas phase outlet of the second-stage cyclone separator is connected with an inlet of a third-stage cyclone separator, and the bottom of the third-stage cyclone separator is connected with a third-stage receiving hopper through a pipeline; the third-stage receiving hopper is connected with a waste powder tank through a pipeline; and an outlet of the second-stage cyclone discharging hopper and an outlet of the waste powder tank are gathered at the fluidized bed removing pipelines of the fine powder tank A and the fine powder tank B through pipelines. According to the utility model, high-efficiency recycling of silicon powder and a catalyst in a gas phase at the top of the fluidized bed is realized, components in the fluidized bed are stabilized, and the discharge of silicon slurry is reduced.

Description

Technical Field

[0001] The utility model relates to a device for producing organic silicon monomers, belonging to the technical field of organic silicon production. Background Art

[0002] Organosilicon materials are a new type of material developed only in recent decades. They are primarily categorized into four main categories: silicone rubber, silicone oil, silane coupling agents, and silicone resin. They are widely used in industries such as aerospace, pharmaceutical engineering, and machinery manufacturing. Currently, the industrial production of organosilicon monomers utilizes a direct synthesis process, involving a gas-solid phase reaction between methyl chloride and silicon powder within a fluidized bed reactor. The reaction products are then separated and purified in a cyclone separator, where most of the silicon powder is recovered. Domestic organosilicon monomer synthesis technology generally utilizes a multi-stage cyclone system with intermittent return of fine powder to the bed. Specifically, the first cyclone recovers fine powder, which is then discharged from a hopper into a fine powder tank. The silicon powder in the tank is then returned to the bed at regular intervals (5-30 minutes) through loss-in-weight metering. The second cyclone recovers fine powder, which is then discharged from a hopper into a fine powder tank. The silicon powder in the tank is then returned to the bed at regular intervals (20-60 minutes) through loss-in-weight metering. The current technology generally has the problem of poor matching of the efficiency of cyclones at all levels and low overall efficiency. First, it may cause a large amount of impurities to be carried back to the bed after the first-level cyclone or the second-level cyclone receives the material, which deteriorates the reaction. Second, a large amount of solids not collected by the cyclone enters the wet dust removal system, resulting in the generation of a large amount of waste slurry. Summary of the Invention

[0003] The utility model performs three-stage cyclone separation on the gas-solid mixture at the fluidized bed outlet, reasonably sets the efficiency of each stage of cyclone, improves the overall efficiency, and simultaneously enables graded cutting and separation of solids in the gas phase, thereby improving the reaction stability of the fluidized bed and reducing hazardous waste emissions.

[0004] The solution of the utility model is: a silicone monomer synthesis aggregate return system includes a fluidized bed top connected to a first-stage cyclone separator via a pipeline, the first-stage cyclone separator is connected to a first-stage cyclone separator receiving hopper via a pipeline, the first-stage cyclone separator receiving hopper is connected to a fine powder tank A and a fine powder tank B via pipelines respectively, and the fine powder tank A and the fine powder tank B are connected to an inlet at the bottom of the fluidized bed via pipelines respectively.

[0005] Valves are provided on the connecting pipes from the receiving hopper of the first-stage cyclone separator to the fine powder tank A and the fine powder tank B; valves are provided on the connecting pipes from the fine powder tank A and the fine powder tank B to the fluidized bed.

[0006] The top of the first-stage cyclone separator is connected to the second-stage cyclone separator through a pipeline, the bottom of the second-stage cyclone separator is connected to the second-stage cyclone separator receiving hopper, the bottom of the second-stage cyclone separator receiving hopper is connected to the second-stage cyclone separator discharge hopper, and the pipeline at the bottom of the second-stage cyclone separator discharge hopper converges to the pipeline of fine powder tank A and fine powder tank B entering the fluidized bed.

[0007] A valve is installed on the pipe connecting the secondary cyclone discharge hopper to the fluidized bed. The top of the secondary cyclone is connected to the tertiary cyclone via a pipe. The bottom of the tertiary cyclone is connected to the tertiary cyclone receiving hopper, which is then connected to the waste powder tank. A portion of the waste powder tank is piped to the fluidized bed feed pipes A and fine powder tank B, while another portion is connected to the waste collection area. A valve is installed on the pipe connecting the waste powder tank to the fluidized bed.

[0008] The efficiency of the first-stage cyclone separator is 80-90%; the efficiency of the second-stage cyclone separator is 80-90%; the efficiency of the third-stage cyclone separator is 85-95%; and the total cyclone efficiency is greater than 99.5%.

[0009] The three-stage cyclone separator is a multi-tube cyclone structure, that is, the three-stage cyclone shell has 2-10 small cyclone separators of the same specifications built in. The gas-solid mixture at the inlet of the three-stage cyclone enters the built-in cyclone through the built-in evenly distributed connecting pipes for gas-solid separation.

[0010] Advantages of this utility model:

[0011] (1) A three-stage cyclone separator is set up, and the efficiency of each cyclone is reasonably distributed, which can realize the reasonable collection and return of the solid phase to the bed or discharge according to the particle size gradient, and stabilize the fluidized bed reaction. (2) The three-stage cyclone is set up with a multi-tube structure, which is highly efficient and can reduce the entrainment of gas phase silicon powder and reduce the output of waste slurry. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 : Diagram of the device structure of the present invention. Including: 1. Fluidized bed; 2. First-stage cyclone separator; 3. First-stage cyclone separator receiving hopper; 4. Fine powder tank A; 5. Fine powder tank B; 6. Second-stage cyclone separator; 7. Second-stage cyclone separator receiving hopper; 8. Second-stage cyclone separator discharge hopper; 9. Third-stage cyclone separator; 10. Third-stage cyclone separator receiving hopper; 11. Waste powder tank. DETAILED DESCRIPTION

[0013] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Each embodiment is intended only to illustrate the technical concept and features of the present invention. Its purpose is to enable those familiar with the art to understand the contents of the present invention and implement them accordingly. It is not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention shall be included within the scope of protection of the present invention.

[0014] Example 1

[0015] A recycling system for organic silicon monomer synthesis aggregates includes: the top of a fluidized bed is connected to a first-stage cyclone separator via a pipeline, the first-stage cyclone separator is connected to a first-stage cyclone separator receiving hopper via a pipeline, the first-stage cyclone separator receiving hopper is connected to a fine powder tank A and a fine powder tank B via pipelines, respectively, and the fine powder tank A and the fine powder tank B are connected to an inlet at the bottom of the fluidized bed via pipelines.

[0016] Valves are provided on the connecting pipes from the receiving hopper of the first-stage cyclone separator to the fine powder tank A and the fine powder tank B; valves are provided on the connecting pipes from the fine powder tank A and the fine powder tank B to the fluidized bed.

[0017] The top of the first-stage cyclone separator is connected to the second-stage cyclone separator through a pipeline, the bottom of the second-stage cyclone separator is connected to the second-stage cyclone separator receiving hopper, the bottom of the second-stage cyclone separator receiving hopper is connected to the second-stage cyclone separator discharge hopper, and the pipeline at the bottom of the second-stage cyclone separator discharge hopper converges to the pipeline of fine powder tank A and fine powder tank B entering the fluidized bed.

[0018] A valve is installed on the pipe connecting the secondary cyclone discharge hopper to the fluidized bed. The top of the secondary cyclone is connected to the tertiary cyclone via a pipe. The bottom of the tertiary cyclone is connected to the tertiary cyclone receiving hopper, which is then connected to the waste powder tank. A portion of the waste powder tank is piped to the fluidized bed feed pipes A and fine powder tank B, while another portion is connected to the waste collection area. A valve is installed on the pipe connecting the waste powder tank to the fluidized bed.

[0019] The efficiency of the first-stage cyclone separator is 80-90%; the efficiency of the second-stage cyclone separator is 80-90%; the efficiency of the third-stage cyclone separator is 85-95%; and the total cyclone efficiency is greater than 99.5%.

[0020] The three-stage cyclone separator is a multi-tube cyclone structure, that is, the three-stage cyclone shell has four small cyclone separators of the same specifications built in. The gas-solid mixture at the inlet of the three-stage cyclone enters the built-in cyclone through the built-in evenly distributed connecting pipes for gas-solid separation.

[0021] Example 2

[0022] The process steps for the organic silicon monomer synthesis aggregate recycling device of Example 1 are as follows: silicon powder and methyl chloride react within a fluidized bed. The reaction products, along with unreacted silicon powder and methyl chloride, are recovered as fine powder by a primary cyclone outside the bed. The fine powder is then discharged through a hopper to fine powder tank A. After 30 minutes, tank A receives 17 tons of material. The valve for fine powder B in the hopper is opened, and the valve for fine powder tank A is closed. Tank A is pressurized with nitrogen to approximately 0.5 MPa and feeds the fluidized bed once every 5 minutes. During this time, the on-off valve in the lower pipeline of the fine powder tank is opened. The amount of fine powder returned to the bed is controlled by monitoring the fine powder tank weighing instrument to ensure that all 17 tons of fine powder are returned to the bed within 30 minutes. After this, the on-off valve in the lower pipeline is closed. Fine powder tanks A and B alternately receive and recycle material every half hour. The secondary cyclone separator collects approximately 5 tons of material per hour, which enters the secondary cyclone discharge hopper and is returned to the bed every 10-15 minutes, ensuring that all fine powder is evenly returned within 1 hour. The three-stage cyclone separator can aggregate 0.95 tons of material per hour. The fine powder collected by the three-stage cyclone will be returned to the fluidized bed or discharged according to the fluidized bed operation indicators or fine powder component analysis results.

Claims

1. A silicone monomer synthesis aggregate recycling system, characterized in that: The top of the fluidized bed (1) is connected to the first-stage cyclone separator (2) via a pipeline, the first-stage cyclone separator (2) is connected to the first-stage cyclone separator receiving hopper (3) via a pipeline, the first-stage cyclone separator receiving hopper (3) is connected to the fine powder tank A (4) and the fine powder tank B (5) via pipelines, respectively, and the fine powder tank A (4) and the fine powder tank B (5) are connected to the bottom inlet of the fluidized bed (1) via pipelines.

2. The organic silicon monomer synthesis aggregate recycling system according to claim 1, characterized in that: Valves are provided on the connecting pipes from the first-stage cyclone separator receiving hopper (3) to the fine powder tank A (4) and the fine powder tank B (5); valves are provided on the connecting pipes from the fine powder tank A (4) and the fine powder tank B (5) to the fluidized bed (1).

3. The organic silicon monomer synthesis aggregate recycling system according to claim 1, characterized in that: The top of the first-stage cyclone separator (2) is connected to the second-stage cyclone separator (6) via a pipeline, the bottom of the second-stage cyclone separator (6) is connected to the second-stage cyclone separator receiving hopper (7), the bottom of the second-stage cyclone separator receiving hopper (7) is connected to the second-stage cyclone separator discharge hopper (8), and the pipeline at the bottom of the second-stage cyclone separator discharge hopper (8) is connected to the pipeline of the fine powder tank A and the fine powder tank B entering the fluidized bed (1).

4. The organic silicon monomer synthesis aggregate recycling system according to claim 3, characterized in that: A valve is provided on the connecting pipe from the secondary rotary discharge hopper (8) to the fluidized bed (1).

5. The organic silicon monomer synthesis aggregate recycling system according to claim 2, characterized in that: The top of the secondary cyclone separator (6) is connected to the tertiary cyclone separator (9) through a pipeline, the bottom of the tertiary cyclone separator (9) is connected to the tertiary cyclone separator receiving hopper (10), the bottom of the tertiary cyclone separator receiving hopper (10) is connected to the waste powder tank (11), a part of the waste powder tank (11) is collected through a pipeline to the pipeline of A and the fine powder tank B into the fluidized bed (1), and a part is connected to the waste collection area.

6. The organic silicon monomer synthesis aggregate recycling system according to claim 5, characterized in that: A valve is provided on the pipeline from the waste powder tank (11) to the fluidized bed (1).

7. The organic silicon monomer synthesis aggregate recycling system according to claim 5, characterized in that: The three-stage cyclone separator (9) is a multi-tube cyclone, that is, the three-stage cyclone shell has 2-10 cyclone separators of the same specifications built in. The gas-solid phase mixture at the inlet of the three-stage cyclone enters the built-in cyclone through the built-in uniformly distributed connecting pipes for gas-solid phase separation.

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