Preparation equipment and process of hollow glass microspheres for distributed floating body

Abstract

The invention discloses equipment and a process for preparing hollow glass microspheres for a distributed floating body, specifically, a hollow and porous-wall basic sphere structure design is adopted, and then a dipping strengthening and surface plugging process is adopted, so that the strength of a shell layer is specifically improved, surface pores are plugged, and the water absorption rate is reduced; meanwhile, the surface epoxy shell layer is also used as a transition layer between the small balls and the resin matrix when the distributed floating body is produced.

Description

Technical Field

[0001] This invention specifically relates to the field of hollow glass microsphere technology, and more specifically to the equipment and process for preparing hollow glass microspheres for distributed floating bodies. Background Technology

[0002] Distributed floating bodies (such as deep-sea buoyancy materials and composite foam floats) are important lightweight structural materials with wide applications in marine engineering, aerospace, and special vehicles. The core functional unit of distributed floating bodies—hollow glass microspheres—directly determines the density, strength, pressure resistance, and interfacial bonding performance with the resin matrix. However, existing preparation technologies and the resulting products have the following technical drawbacks in meeting the requirements of high-performance distributed floating bodies:

[0003] The hollow glass microspheres currently produced by various processes focus on achieving high hollowness and low density. However, their shells often suffer from insufficient structural compactness, numerous micropores, and low strength. In other words, when applied to distributed floats, these microspheres exhibit significant shortcomings: First, the shell's mechanical strength is insufficient, making it prone to breakage under the stress conditions of resin infusion, curing, and subsequent service, leading to localized float failure. Second, the presence of open pores on the surface results in high water absorption (WA), causing the microspheres to lose buoyancy due to increased weight from water absorption when exposed to humid or underwater environments for extended periods, potentially leading to interface degradation. Third, the limited chemical compatibility and physical bonding between the glassy surface and the organic resin matrix make the interface a weak point for stress concentration and crack propagation, affecting the overall mechanical properties and durability of the float. Summary of the Invention

[0004] Therefore, this invention proposes a preparation equipment and process for hollow glass microspheres for distributed floating bodies to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a preparation apparatus and process for hollow glass microspheres for distributed floating bodies, comprising the following process steps:

[0006] Step 1: Select polystyrene spheres with a diameter of 5-8 mm as the core;

[0007] Step 2: Mix the glass powder and calcium carbonate foaming agent evenly to obtain the coated powder, wherein the glass powder has a mesh size of 325 and the calcium carbonate foaming agent has a mesh size of 1000.

[0008] Step 3: Prepare a slurry by mixing glass powder, polyvinyl alcohol, and water. Then, place polystyrene spheres into the slurry and coat them with a thin shell with a thickness of 0.5~1mm. Dry the slurry at a temperature of 60~70℃ for later use.

[0009] Step 4: Put the polystyrene spheres coated with thin shells from Step 3 and the coating powder from Step 2 into a high-speed high-strength granulator, spray a 0.2% dilute polyvinyl alcohol solution as a sphere binder, and make hollow glass microspheres with a diameter of 1.5~2cm into semi-finished products, and dry them at a temperature of 60~70℃ for later use.

[0010] Step 5: Place the dried hollow glass microsphere semi-finished product from Step 4 into a rotary expansion furnace and expand and foam at a high temperature of 800~850℃ for 20~30 minutes. Then place it into the cooling section and cool it to room temperature in stages to obtain hollow lightweight porous spheres with a diameter of 3~5cm.

[0011] Step 6: Immerse the hollow, lightweight, porous spheres from Step 5 in a water glass solution with a modulus of 2.8 and a concentration of 20 wt.% for 30 minutes. After removing and drying them, dry them at 80°C and place them in a rotary expansion furnace for rotary heat treatment at 400°C for 20-30 minutes. After cooling, spray a thin layer of about 0.1 mm thick with dilute E51 epoxy resin onto the surface of the spheres. Cure the coating at room temperature to obtain hollow glass microspheres.

[0012] Optionally, the rotary expansion furnace includes:

[0013] Erecting the frame;

[0014] The furnace body is fixed on the upright frame, and the furnace body is provided with a high temperature expansion chamber, a primary low temperature cooling chamber and a secondary low temperature cooling chamber arranged from top to bottom;

[0015] A rotary heating system is installed in a high-temperature expansion chamber. The rotary heating system can circulate and tumble the hollow glass microsphere semi-finished product inside for high-temperature expansion and foaming treatment.

[0016] The primary cooler is located in the primary low-temperature cooling chamber and is connected to the rotary heating system via a first electric switch.

[0017] And a oscillating cooling mechanism, which is located in the secondary low-temperature cooling chamber and is connected to the primary cooler via a second electric gate.

[0018] Optionally, the furnace body is equipped with a temperature measuring system for real-time monitoring of the internal temperature of the rotary heating system, the primary cooler, and the oscillating cooling mechanism, and transmits the temperature measuring data to the temperature control system in real time. The temperature control system is capable of controlling the temperature of the rotary heating system, the primary cooler, and the oscillating cooling mechanism.

[0019] Optionally, the oscillating cooling mechanism includes:

[0020] The rotating shell is rotatably mounted in the secondary cryogenic cooling chamber and is driven by a motor fixed to the bottom of the stand;

[0021] The secondary cooling section is mounted on the rotating housing via elastic supports.

[0022] And push cylinders, of which multiple are provided and are installed in a circumferential array on the bottom inner wall of the rotating shell. The multiple push cylinders can cyclically push the secondary cooling section in different directions to accelerate the heat exchange rate between the hollow glass microsphere semi-finished product and the cooling airflow in the secondary cooling section.

[0023] Optionally, the elastic support includes:

[0024] The cap is fixed to the inner bottom surface of the secondary cooling section;

[0025] The slider is adapted to slide within the cap housing;

[0026] The ball seat is fixed to the inner bottom surface of the rotating shell;

[0027] A support base that is adapted to roll onto a ball seat, and the support base and the slider are fixedly connected by a sliding column;

[0028] And a spring, which is wound around the side wall of the slide column and located between the bottom surface of the secondary cooling section and the inner bottom surface of the rotating shell.

[0029] Optionally, under the elastic support of the spring, a sliding space is left between the slider and the inner top surface of the cap.

[0030] Optionally, a rubber pusher block is fixed to the drive end of each of the push cylinders.

[0031] Optionally, a plurality of discharge slots are arranged in a ring on the side wall at the bottom of the secondary cooling section;

[0032] Multiple material discharge ports are arranged in a ring on the side wall at the bottom of the rotating shell. Each material discharge port is connected to the chamber of the secondary low-temperature cooling chamber, and the chamber of the secondary low-temperature cooling chamber is also connected to the discharge hopper installed on the furnace body.

[0033] The present invention employs the above technology and has the following beneficial effects compared with existing technologies:

[0034] 1. In the process of this invention, a hollow, porous wall basic sphere structure is designed, and then an impregnation strengthening and surface sealing process is used to specifically improve the shell strength, seal the surface pores, and reduce the water absorption rate; at the same time, the surface epoxy shell also serves as a transition layer between the spheres and the resin matrix when producing distributed floating bodies.

[0035] 2. In the device of the present invention, the secondary cooling section is pushed in multiple directions by the cylinder circulation, and the elastic support makes the cooling section generate compound micro-vibration and oscillation, which significantly enhances the disturbance contact between the material and the cooling airflow, accelerates the heat exchange rate, and shortens the cooling time. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the rotary expansion furnace in this invention;

[0037] Figure 2 This is a schematic diagram of the internal structure of the rotary expansion furnace in this invention;

[0038] Figure 3 for Figure 2 An enlarged schematic diagram of part A in the middle;

[0039] Figure 4 This is a cross-sectional view of the hollow glass microspheres in this invention.

[0040] In the diagram: 1. High-temperature expansion chamber; 2. Primary low-temperature cooling chamber; 3. Frame; 4. Motor; 5. Discharge hopper; 6. Secondary low-temperature cooling chamber; 7. Temperature control system; 8. Temperature measurement system; 9. Primary cooler; 10. Porous layer; 11. Impregnated reinforcement layer; 12. Epoxy resin layer; 13. Hollow layer;

[0041] 601. Rotating shell; 602. Push cylinder; 603. Support base; 604. Ball seat; 605. Spring; 606. Sliding column; 607. Sliding block; 608. Cap shell; 609. Discharge chute; 610. Secondary cooling section. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example: Please refer to the appendix Figure 1-4 This invention provides a technical solution: a preparation device and process for hollow glass microspheres for distributed floating bodies, which includes the following process steps:

[0044] Step 1: Select polystyrene spheres with a diameter of 5-8 mm as the core;

[0045] It should be noted that the polystyrene spheres, which serve as the core, are burned off at high temperatures, leaving hollow pores and reducing the specific gravity of the spheres.

[0046] Step 2: Mix glass powder and calcium carbonate (or magnesium carbonate) foaming agent evenly to obtain coated powder, wherein the glass powder has a mesh size of 325 and the calcium carbonate (or magnesium carbonate) foaming agent has a mesh size of 1000.

[0047] The glass powder accounts for 100% of the total formula, and the silicon carbide powder in the foaming agent accounts for 0.1-0.2% of the total formula.

[0048] Step 3: Prepare a slurry by mixing glass powder (100%), polyvinyl alcohol (+1.5%), and water (+35%). Then, place polystyrene spheres into the slurry and coat them with a thin shell with a thickness of 0.5~1mm. Dry the slurry at a temperature of 60~70℃ for later use.

[0049] Step 4: Put the polystyrene spheres coated with thin shells from Step 3 and the coating powder from Step 2 into a high-speed high-strength granulator, spray a 0.2% dilute polyvinyl alcohol solution as a sphere binder, and make hollow glass microspheres with a diameter of 1.5~2cm into semi-finished products, and dry them at a temperature of 60~70℃ for later use.

[0050] Step 5: Place the dried hollow glass microsphere semi-finished product from Step 4 into a rotary expansion furnace and expand and foam at a high temperature of 800~850℃ for 20~30 minutes. Then place it into the cooling section and cool it to room temperature in stages to obtain hollow lightweight porous spheres with a diameter of 3~5cm.

[0051] It should be noted that the strength and water absorption rate of the hollow lightweight porous spheres at this time do not meet the requirements of distributed floating bodies, namely, they must not break or absorb water under a static pressure of 3M underwater, have a cylinder pressure strength greater than 3MPa, and a water absorption rate of less than 0.3%.

[0052] Step 6: Immerse the hollow lightweight porous spheres from Step 5 in a water glass solution with a modulus of 2.8 (or a modulus of 3.0 or higher) and a concentration of 20 wt.% for 30 minutes to increase the density of the spheres. After removing and drying, dry them at 80°C and place them in a rotary expansion furnace for rotary heat treatment at 400°C for 20-30 minutes. After cooling, spray a thin layer of dilute E51 epoxy resin about 0.1 mm thick on the surface of the spheres to increase density, reduce water absorption, and serve as a transition layer for the distributed floating aggregate spheres. Then cure at room temperature to obtain hollow glass microspheres.

[0053] In other words, the hollow glass microspheres are composed of a hollow layer 13, a porous layer 10, an impregnated reinforcing layer 11, and an epoxy resin layer 12 from the inside out.

[0054] In this embodiment, the rotary expansion furnace includes:

[0055] Frame 3;

[0056] The furnace body is fixed on the support frame 3. The furnace body is provided with a high temperature expansion chamber 1, a primary low temperature cooling chamber 2 and a secondary low temperature cooling chamber 6 arranged from top to bottom.

[0057] The rotary heating system is installed in the high-temperature expansion chamber 1. The rotary heating system can circulate and turn the hollow glass microsphere semi-finished products inside for high-temperature expansion and foaming treatment.

[0058] The primary cooler 9 is located inside the primary low-temperature cooling chamber 2 and is connected to the rotary heating system via a first electric switch.

[0059] And a oscillating cooling mechanism, which is installed in the secondary low-temperature cooling chamber 6 and is connected to the primary cooler 9 through a second electric gate.

[0060] It should be noted that the high-temperature expansion chamber, the first-stage low-temperature cooling chamber, and the second-stage low-temperature cooling chamber are set up in sections. With the help of electric gates, the material is transferred step by step to achieve a smooth temperature transition, avoid the microspheres from breaking or deforming due to sudden cooling, and ensure the integrity and performance consistency of the product.

[0061] In this embodiment, a temperature measuring system is installed on the furnace body to monitor the internal temperature of the rotary heating system, the primary cooler 9, and the oscillating cooling mechanism in real time, and transmits the temperature measuring data to the temperature control system in real time. The temperature control system can control the temperature of the rotary heating system, the primary cooler 9, and the oscillating cooling mechanism.

[0062] In this embodiment, the oscillating cooling mechanism includes:

[0063] The rotating shell 601 is rotatably installed in the secondary cryogenic cooling chamber 6 and is driven by the motor 4 fixed to the bottom of the support frame 3;

[0064] The secondary cooling section 610 is mounted on the rotating housing 601 via an elastic support member;

[0065] And push cylinders 602, of which multiple are provided and are installed in a circumferential array on the bottom inner wall of the rotating shell 601. Multiple push cylinders 602 can cyclically push the secondary cooling section 610 in different directions to accelerate the heat exchange rate between the hollow glass microsphere semi-finished product and the cooling airflow in the secondary cooling section 610.

[0066] In this embodiment, the elastic support includes:

[0067] The cap 608 is fixed to the inner bottom surface of the secondary cooling section 610;

[0068] Slider 607, whose sliding adaptation is set inside cap 608;

[0069] Ball seat 604, which is fixed to the inner bottom surface of rotating shell 601;

[0070] The support base 603 is adapted to roll with the ball seat 604, and the support base 603 and the slider 607 are fixedly connected by the sliding post 606.

[0071] And spring 605, which is wound around the side wall of slide column 606 and located between the bottom surface of secondary cooling section 610 and the inner bottom surface of rotating shell 601.

[0072] In this embodiment, under the elastic support of the spring 605, there is a sliding space between the slider 607 and the inner top surface of the cap 608.

[0073] It should be noted that by using a push cylinder to circulate and push the secondary cooling section in multiple directions, combined with the elastic support components, the cooling section generates a composite micro-vibration and oscillation, which significantly enhances the disturbance contact between the material and the cooling airflow, accelerates the heat exchange rate, and shortens the cooling time.

[0074] Furthermore, the elastic support components enable the secondary cooling section to have buffering and self-adaptive capabilities when subjected to vibration, which can effectively transmit vibration force and protect the device structure from rigid impact damage, thereby improving the reliability and lifespan of the equipment in long-term operation.

[0075] In this embodiment, a rubber push block is fixed to the drive end of each push cylinder 602.

[0076] In this embodiment, a plurality of discharge slots 609 are arranged in a ring on the side wall at the bottom of the secondary cooling section 610.

[0077] Multiple material discharge ports are arranged in a ring on the side wall at the bottom of the rotating shell 601. Each material discharge port is connected to the chamber of the secondary low-temperature cooling chamber 6, and the chamber of the secondary low-temperature cooling chamber 6 is also connected to the discharge hopper 5 installed on the furnace body.

[0078] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. Equipment and process for preparing hollow glass microspheres for distributed floating bodies, characterized in that, It includes the following process steps: Step 1: Select polystyrene spheres with a diameter of 5-8 mm as the core; Step 2: Mix the glass powder and calcium carbonate foaming agent evenly to obtain the coated powder, wherein the glass powder has a mesh size of 325 and the calcium carbonate foaming agent has a mesh size of 1000. Step 3: Prepare a slurry by mixing glass powder, polyvinyl alcohol, and water. Then, place polystyrene spheres into the slurry and coat them with a thin shell with a thickness of 0.5~1mm. Dry the slurry at a temperature of 60~70℃ for later use. Step 4: Put the polystyrene spheres coated with thin shells from Step 3 and the coating powder from Step 2 into a high-speed high-strength granulator, spray a 0.2% dilute polyvinyl alcohol solution as a sphere binder, and make hollow glass microspheres with a diameter of 1.5~2cm into semi-finished products, and dry them at a temperature of 60~70℃ for later use. Step 5: Place the dried hollow glass microsphere semi-finished product from Step 4 into a rotary expansion furnace and expand and foam at a high temperature of 800~850℃ for 20~30 minutes. Then place it into the cooling section and cool it to room temperature in stages to obtain hollow lightweight porous spheres with a diameter of 3~5cm. Step 6: Immerse the hollow, lightweight, porous spheres from Step 5 in a water glass solution with a modulus of 2.8 and a concentration of 20 wt.% for 30 minutes. After removing and drying them, dry them at 80°C and place them in a rotary expansion furnace for rotary heat treatment at 400°C for 20-30 minutes. After cooling, spray a thin layer of about 0.1 mm thick with dilute E51 epoxy resin onto the surface of the spheres. Cure the coating at room temperature to obtain hollow glass microspheres.

2. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 1, characterized in that: The rotary expansion furnace includes: Frame erection (3); The furnace body is fixed on the support frame (3), and the furnace body is provided with a high temperature expansion chamber (1), a primary low temperature cooling chamber (2) and a secondary low temperature cooling chamber (6) arranged from top to bottom. A rotary heating system is installed in a high-temperature expansion chamber (1). The rotary heating system can circulate and turn the hollow glass microsphere semi-finished product inside for high-temperature expansion and foaming treatment. A primary cooler (9) is installed in a primary low-temperature cooling chamber (2) and is connected to a rotary heating system via a first electric gate. And a swing-type cooling mechanism, which is located in the secondary low-temperature cooling chamber (6) and is connected to the primary cooler (9) through a second electric gate.

3. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 2, characterized in that: The furnace body is equipped with a temperature measuring system (7) for real-time monitoring of the internal temperature of the rotary heating system, the primary cooler (9), and the oscillating cooling mechanism, and transmits the temperature measuring data to the temperature control system in real time. The temperature control system (7) can control the temperature of the rotary heating system, the primary cooler (9), and the oscillating cooling mechanism.

4. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 2, characterized in that: The oscillating cooling mechanism includes: The rotating shell (601) is rotatably installed in the secondary cryogenic cooling chamber (6) and is driven by a motor (4) fixed to the bottom of the stand (3); A secondary cooling section (610) is mounted on a rotating housing (601) via a flexible support. And push cylinders (602), which are provided in multiples and are installed in a circumferential array on the bottom inner wall of the rotating shell (601). The multiple push cylinders (602) can cyclically push the secondary cooling section (610) in different directions to accelerate the heat exchange rate between the hollow glass microsphere semi-finished product and the cooling airflow in the secondary cooling section (610).

5. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 4, characterized in that: The elastic support member includes: Cap (608), which is fixed to the inner bottom surface of the secondary cooling section (610); The slider (607) is adapted to slide inside the cap (608); A ball seat (604) is fixed to the inner bottom surface of the rotating shell (601); A support base (603) is adapted to roll with a ball seat (604), and the support base (603) and the slider (607) are fixedly connected by a sliding column (606); And a spring (605) which is wound around the side wall of the slide (606) and located between the bottom surface of the secondary cooling section (610) and the inner bottom surface of the rotating shell (601).

6. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 5, characterized in that: Under the elastic support of the spring (605), there is a sliding space between the slider (607) and the inner top surface of the cap (608).

7. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 5, characterized in that: Each of the push cylinders (602) has a rubber push block fixed to its drive end.

8. The equipment and process for preparing hollow glass microspheres for distributed floating bodies according to claim 5, characterized in that: Multiple discharge slots (609) are arranged in a ring on the side wall at the bottom of the secondary cooling section (610). Multiple material discharge ports are arranged in a ring on the side wall at the bottom of the rotating shell (601). Each material discharge port is connected to the chamber of the secondary low temperature cooling chamber (6), and the chamber of the secondary low temperature cooling chamber (6) is also connected to the discharge hopper (5) installed on the furnace body.

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