Preparation process of silicon dioxide aerogel integrated ball-milling and vacuum adsorption phase change material

Abstract

The invention discloses a preparation process of a silicon dioxide aerogel integrated ball-milling and vacuum adsorption phase-change material, relates to the technical field of phase-change materials, and aims to solve the problems of complicated operation, low efficiency and poor practicability due to the adoption of a conventional dipping-adsorption method during preparation of the phase-change material in the prior art. The method comprises the following steps: step 1, pretreatment: silicon dioxide aerogel felt is fed into a treatment tower through a raw material feed opening, and raw materials enter a crushing chamber for crushing treatment; 2, ball-milling treatment is conducted, specifically, a coarse material enters a ball-milling chamber through a coarse material discharging opening and a ball-milling feeding opening, and coarse material ball-milling is started; step 3, sieving treatment: after ball milling is finished, sieving the silicon dioxide aerogel micro powder layer by layer; and step 4, loading treatment: inputting the silicon dioxide aerogel micro powder into a vacuum adsorption device, inputting octadecane liquid, carrying out vacuum loading in a vacuum chamber of the vacuum adsorption device, and after loading is finished, enabling a product to flow into a loaded product storage tank through a loaded product outlet to be stored.

Description

Technical Field

[0001] The invention relates to the technical field of phase change materials, and in particular to a preparation process of a silicon dioxide aerogel integrated ball milling and vacuum adsorption phase change material. Background Art

[0002] As a nanoporous material with extremely high porosity, high specific surface area and low thermal conductivity, silica aerogel has shown broad application prospects in many fields such as thermal insulation, energy storage, and adsorption. The refinement of felt-like silica aerogel is mostly done by mechanical method, that is, silica aerogel powder is obtained by mechanical crushing and then drying. Phase change materials are widely used in energy storage and temperature control in the fields of construction, textiles, energy, etc. because they can absorb or release a large amount of latent heat at a specific temperature. By compounding silica aerogel with excellent performance with phase change materials, not only can the thermal insulation and pressure resistance of silica aerogel be maximized, but also the problems of flammability, easy leakage and poor thermal conductivity of single solid-liquid phase change materials can be solved, and high heat storage performance can be achieved; For example, the patent with announcement number CN107523275A (a method for preparing a flexible silica aerogel-based phase change composite material): its preparation method is: introducing trimethylmethoxysilane as a new precursor, preparing a flexible silica aerogel by adjusting the ratio of different silane precursors and solvents, and then selecting a suitable phase change core material, and using a vacuum impregnation method to obtain a silica aerogel-based phase change composite material; Although the flexible silica aerogel material prepared by the above-mentioned prior art can be used to prepare phase change composite materials with composite phase change core materials due to its porosity, the traditional conventional impregnation-adsorption method is not adopted when preparing the phase change material, and the operation is complicated, the efficiency is low, and the practicality is poor. Therefore, the market urgently needs to develop a silica aerogel integrated ball milling and vacuum adsorption phase change material preparation process to help people solve the existing problems. Summary of the invention

[0003] The purpose of the present invention is to provide a preparation process of silica aerogel integrated ball milling and vacuum adsorption phase change material to solve the problem that the phase change material is prepared by the traditional conventional impregnation-adsorption method proposed in the above background technology, which is complicated to operate, low in efficiency and poor in practicality.

[0004] To achieve the above object, the present invention provides the following technical solution: a preparation process of a silica aerogel integrated ball milling and vacuum adsorption phase change material, comprising the following steps: Step 1: Pretreatment, adding the silica aerogel felt into the processing tower through the raw material discharge port, the raw material enters the crushing chamber, and the blade is driven by the rotating shaft to crush the silica aerogel felt; Step 2: ball milling treatment, after the raw material is crushed, it enters the ball mill chamber through the coarse material discharge port and the ball mill feed port to start coarse material ball milling; Step 3: Screening treatment: after the ball milling is completed, the silica aerogel powder discharge port below the ball milling chamber is opened, and the silica aerogel powder falls due to gravity through the silica aerogel powder discharge port into the sieve plate chamber, and the silica aerogel powder is screened layer by layer. The sieved silica aerogel powder is collected into the silica aerogel powder storage tank through the discharge pipe; Step 4: Loading treatment, then the silica aerogel powder in the silica aerogel powder storage tank is fed into the vacuum adsorption device through the silica aerogel powder feed port, and octadecane liquid is fed into the octadecane feed port, and vacuum loading is performed in the vacuum chamber of the vacuum adsorption device. After the loading is completed, the product flows into the loaded product storage tank through the loaded product outlet for storage; Wherein, the processing tower comprises a crushing chamber, a ball milling chamber and a sieve plate chamber, the crushing chamber, the ball milling chamber and the sieve plate chamber are arranged in sequence from top to bottom, the raw material discharge port is arranged above the processing tower, the blades are provided with multiple groups, the blades are fixedly installed on the outside of the rotating shaft, the rotating shaft is arranged inside the crushing chamber, the coarse material discharge port is arranged below the crushing chamber, the ball mill feed port is arranged above the ball milling chamber, the silica aerogel powder discharge port is arranged below the ball milling chamber, and the discharge pipe is arranged below the processing tower; The vacuum adsorption device comprises an octadecane feed port, a silica aerogel powder feed port and a loaded product outlet, and the loaded product outlet of the vacuum adsorption device is connected to the input end of the loaded product storage tank through a pipeline; The feed pipe is connected to the input end of the silica aerogel micropowder storage tank, the output end of the silica aerogel micropowder storage tank is connected to the silica aerogel micropowder feed port of the vacuum adsorption device through a pipeline, and the octadecane feed port of the vacuum adsorption device is connected to the octadecane storage tank through a pipeline.

[0005] Preferably, a reflux port is provided on one side of the sieve plate chamber, and the reflux port is connected to the raw material discharge port through a pipeline.

[0006] Preferably, a maintenance hole is provided on one side of the crushing chamber.

[0007] Preferably, the ball milling chamber is provided with grinding beads, and a plurality of grinding beads are provided.

[0008] Preferably, four coarse material discharge ports and four ball mill feed ports are provided, and the four coarse material discharge ports correspond to the four ball mill feed ports one by one.

[0009] Preferably, four silica aerogel powder feeding ports are provided.

[0010] Preferably, a heating jacket is provided on the outside of the crushing chamber.

[0011] Preferably, a sieve plate layer is provided inside the sieve plate chamber, and the sieve plate layer of the sieve plate chamber is provided with four layers of sieve plates.

[0012] Preferably, the sieve plate layers of the sieve plate chamber are, from bottom to top, 12500 mesh sieve plates, 8000 mesh sieve plates, 6250 mesh sieve plates and 5000 mesh sieve plates.

[0013] Preferably, a powder delivery pump is provided on the pipeline connecting the silica aerogel powder storage tank and the vacuum adsorption device, and a phase-changing material delivery pump is provided on the pipeline connecting the vacuum adsorption device and the octadecane storage tank.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The invention combines ball milling technology and vacuum adsorption method to effectively fill phase change materials into the pores of silica aerogel to form composite phase change materials, which cleverly combines the thermal insulation performance of silica aerogel and the heat storage performance of phase change materials. The combination of these two technologies not only improves the mixing uniformity of the raw materials, but also ensures that the phase change materials can be more efficiently adsorbed and fixed in the pore structure of the aerogel, thereby enhancing the comprehensive performance of the composite material. Compared with the traditional composite process of silica aerogel and phase change materials, which often focuses on single equipment non-integrated preparation technology, such as focusing on a single ball milling process or focusing on a single adsorption process, the present invention combines ball milling technology and vacuum adsorption, which not only greatly simplifies the preparation process and reduces the complexity of operation, but also achieves a significant improvement in production efficiency and practicality. The integrated integrated grinding and vacuum adsorption technology adopted by the invention has lower cost and simpler operation process, which is conducive to the low-cost and large-scale production of composite materials. Compared with the traditional mechanical direct ball milling and conventional impregnation-adsorption method, this is of great significance for promoting the application of silica aerogel integrated phase change materials in energy storage, temperature control and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic flow chart of a preparation process of a silicon dioxide aerogel integrated ball milling and vacuum adsorption phase change material of the present invention; Figure 2 It is a partial enlarged view of the negative pressure adsorption device of the present invention.

[0016] In the figure: 1. raw material discharge port; 2. rotating shaft; 3. blade; 4. crushing chamber; 5. maintenance hole; 6. coarse material discharge port; 7. ball mill feed port; 8. ball mill chamber; 9. grinding beads; 10. silica aerogel micropowder discharge port; 11. sieve plate chamber; 12. discharge pipe; 13. silica aerogel micropowder storage tank; 14. vacuum adsorption device; 15. octadecane storage tank; 16. loaded product storage tank; 17. octadecane feed port; 18. silica aerogel micropowder feed port; 19. loaded product outlet; 20. reflux port. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0018] See also Figure 1 and Figure 2 , an embodiment provided by the present invention: a preparation process of a silicon dioxide aerogel integrated ball milling and vacuum adsorption phase change material, comprising the following steps: Step 1: pretreatment, the silica aerogel felt is fed into the treatment tower through the raw material discharge port 1, the raw material enters the crushing chamber 4, and the blade 3 is driven by the rotating shaft 2 to crush the silica aerogel felt; Step 2: ball milling. After the raw material is crushed, it enters the ball milling chamber 8 through the coarse material discharge port 6 and the ball mill feed port 7 to start coarse material ball milling. Step 3: Screening treatment. After the ball milling is completed, the silica aerogel powder discharge port 10 below the ball milling chamber 8 is opened, and the silica aerogel powder falls due to gravity through the silica aerogel powder discharge port 10 into the sieve plate chamber 11, and the silica aerogel powder is screened layer by layer. The sieved silica aerogel powder is collected into the silica aerogel powder storage tank 13 through the discharge pipe 12; Step 4: Loading treatment, the silica aerogel powder in the silica aerogel powder storage tank 13 is then fed into the vacuum adsorption device 14 through the silica aerogel powder feed port 18, and octadecane liquid is fed into the vacuum adsorption device 14 through the octadecane feed port 17, and vacuum loading is performed in the vacuum chamber of the vacuum adsorption device 14. After the loading is completed, the product flows into the loaded product storage tank 16 through the loaded product outlet 19 for storage; By combining ball milling technology and vacuum adsorption method, phase change materials can be effectively filled into the pores of silica aerogel to form composite phase change materials, which cleverly combines the thermal insulation performance of silica aerogel and the heat storage performance of phase change materials. The combination of these two technologies not only improves the mixing uniformity of raw materials, but also ensures that the phase change material can be more efficiently adsorbed and fixed in the pore structure of aerogel. Thus, the comprehensive performance of the composite material is enhanced. Compared with the traditional composite process of silica aerogel and phase change material, which often focuses on a single equipment non-integrated preparation technology, such as focusing on a single ball milling process or focusing on a single adsorption process, the present invention combines ball milling technology with vacuum adsorption, which not only greatly simplifies the preparation process and reduces the complexity of operation, but also achieves a significant improvement in production efficiency and practicality. Among them, the processing tower includes a crushing chamber 4, a ball milling chamber 8 and a sieve plate chamber 11, which are arranged in sequence from top to bottom. The raw material discharge port 1 is arranged above the processing tower. The blade 3 is provided with multiple groups to improve the crushing ability of the silica aerogel felt through the raw material. The blade 3 is fixedly installed on the outside of the rotating shaft 2, and the rotating shaft 2 is arranged inside the crushing chamber 4. The lower end of the rotating shaft 2 passes through the ball milling chamber 8 and rotates with the ball milling chamber 8, so that the rotation of the rotating shaft 2 can drive the ball milling chamber 8 to rotate. A driving motor of the rotating shaft 2 is arranged inside the processing tower. , a coarse material discharge port 6 is arranged below the crushing chamber 4, and an electric valve is arranged on the coarse material discharge port 6 to facilitate the downward output of the crushed coarse material; a ball mill feed port 7 is arranged above the ball mill chamber 8; a silica aerogel powder discharge port 10 is arranged below the ball mill chamber 8, and an electric valve is arranged on the silica aerogel powder discharge port 10 to facilitate the output of the ball-milled silica aerogel powder; a discharge pipe 12 is arranged below the processing tower, and an electric valve is also arranged on the discharge pipe 12 to facilitate the output of the screened silica aerogel powder; The vacuum adsorption device 14 includes an octadecane feed port 17, a silica aerogel powder feed port 18, and a loaded product outlet 19. The loaded product outlet 19 of the vacuum adsorption device 14 is connected to the input end of the loaded product storage tank 16 through a pipeline, so that the silica aerogel powder and the octadecane liquid can be vacuum-sucked from different positions of the vacuum adsorption device 14 for mixed loading work; The feed pipe 12 is connected to the input end of the silica aerogel micropowder storage tank 13, so that the prepared silica aerogel micropowder can be input into the silica aerogel micropowder storage tank 13 for storage. The output end of the silica aerogel micropowder storage tank 13 is connected to the silica aerogel micropowder feed port 18 of the vacuum adsorption device 14 through a pipeline. The octadecane feed port 17 of the vacuum adsorption device 14 is connected to the octadecane storage tank 15 through a pipeline. The octadecane storage tank 15 stores octadecane liquid inside, which is beneficial to the preparation of phase change materials.

[0019] Furthermore, a reflux port 20 is provided on one side of the sieve plate chamber 11, and the reflux port 20 is connected to the raw material discharge port 1 through a pipeline, and a conveying device is provided on the pipeline, so that the unscreened silica aerogel powder passes through the reflux port 20 to the raw material discharge port 1 for the next round of ball milling process.

[0020] Furthermore, a maintenance hole 5 is provided on one side of the crushing chamber 4. Through the maintenance hole 5, it is convenient to perform maintenance and cleaning work on the inside of the crushing chamber 4, thereby increasing practicality.

[0021] Furthermore, grinding beads 9 are arranged inside the ball milling chamber 8 , and a plurality of grinding beads 9 are arranged, so that after the silica aerogel felt crushed raw materials are input into the ball milling chamber 8 , ball milling treatment can be performed through the action of the grinding beads 9 .

[0022] Furthermore, four coarse material discharge ports 6 and four ball mill feed ports 7 are provided, and the four coarse material discharge ports 6 correspond to the four ball mill feed ports 7 one by one, so that the crushed silica aerogel felt crushed raw materials can enter the ball mill chamber 8 conveniently.

[0023] Furthermore, four silica aerogel powder feeding ports 10 are provided, so that the silica aerogel powder after ball milling can fall into the sieve plate chamber 11 from four directions, which is beneficial to the dispersion and screening of the silica aerogel powder and increases practicality.

[0024] Furthermore, a heating jacket is provided on the outer side of the crushing chamber 4, which can dry the silica aerogel felt raw material, thereby achieving simultaneous drying and dehydration of the raw material and ball milling pretreatment of the raw material.

[0025] Furthermore, a sieve plate layer is provided inside the sieve plate chamber 11, and the sieve plate layer of the sieve plate chamber 11 is provided with four layers of sieve plates, so as to improve the screening ability of silica aerogel powder. The sieve plate layers of the sieve plate chamber 11 are 12500 mesh sieve plates, 8000 mesh sieve plates, 6250 mesh sieve plates and 5000 mesh sieve plates from bottom to top, respectively, which facilitates obtaining silica aerogel powder of required particle size and increases practicality.

[0026] Furthermore, a powder delivery pump is provided on the pipeline connecting the silica aerogel powder storage tank 13 and the vacuum adsorption device 14. Through the provided powder delivery pump, the silica aerogel powder in the silica aerogel powder storage tank 13 can be conveniently pumped into the vacuum adsorption device 14. A phase-changing material delivery pump is provided on the pipeline connecting the vacuum adsorption device 14 and the octadecane storage tank 15. Through the provided phase-changing material delivery pump, the octadecane liquid in the octadecane storage tank 15 can be conveniently pumped into the vacuum adsorption device 14, which is beneficial to the preparation of phase change materials.

[0027] Working principle: When in use, the silica aerogel felt is fed into the processing tower through the raw material discharge port 1, the raw material enters the crushing chamber 4, and the blade 3 is driven by the rotating shaft 2 to crush the silica aerogel felt. After the raw material is crushed, it enters the ball milling chamber 8 through the coarse material discharge port 6 and the ball mill feed port 7 to start coarse material ball milling. After the ball milling is completed, the silica aerogel powder discharge port 10 below the ball milling chamber 8 is opened, and the silica aerogel powder falls due to gravity through the silica aerogel powder discharge port 10 and enters the sieve plate chamber 11. The silica aerogel powder is screened layer by layer, and the screened silica aerogel powder is collected into the silica aerogel powder storage tank 13 through the feed pipe 12, and then the silica aerogel powder in the silica aerogel powder storage tank 13 is input into the vacuum adsorption device 14 through the silica aerogel powder feed port 18, and octadecane liquid is input through the octadecane feed port 17, and vacuum loading is performed in the vacuum air chamber of the vacuum adsorption device 14. After the loading is completed, the product flows into the load product storage tank 16 through the load product outlet 19 for storage.

[0028] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material, characterized in that: The following steps are involved: Step 1: pretreatment, adding the silica aerogel felt into the treatment tower through the raw material discharge port (1), the raw material enters the crushing chamber (4), and the blade (3) is driven by the rotating shaft (2) to crush the silica aerogel felt; Step 2: ball milling, after the raw material is crushed, it enters the ball milling chamber (8) through the coarse material discharge port (6) and the ball mill feed port (7), and starts coarse material ball milling; Step 3: Screening treatment. After the ball milling is completed, the silica aerogel powder discharge port (10) below the ball milling chamber (8) is opened, and the silica aerogel powder falls due to gravity through the silica aerogel powder discharge port (10) into the sieve plate chamber (11), and the silica aerogel powder is screened layer by layer. The screened silica aerogel powder is collected into the silica aerogel powder storage tank (13) through the discharge pipe (12); Step 4: Loading treatment, the silica aerogel powder in the silica aerogel powder storage tank (13) is then fed into the vacuum adsorption device (14) through the silica aerogel powder feed port (18), and octadecane liquid is fed into the vacuum adsorption device (14) through the octadecane feed port (17), and vacuum loading is performed in the vacuum chamber of the vacuum adsorption device (14). After the loading is completed, the product flows into the loaded product storage tank (16) through the loaded product outlet (19) for storage; The processing tower comprises a crushing chamber (4), a ball milling chamber (8) and a sieve plate chamber (11), wherein the crushing chamber (4), the ball milling chamber (8) and the sieve plate chamber (11) are arranged in sequence from top to bottom, the raw material discharge port (1) is arranged above the processing tower, the blades (3) are provided in multiple groups, the blades (3) are fixedly mounted on the outside of the rotating shaft (2), the rotating shaft (2) is arranged inside the crushing chamber (4), the coarse material discharge port (6) is arranged below the crushing chamber (4), the ball milling feed port (7) is arranged above the ball milling chamber (8), the silica aerogel powder discharge port (10) is arranged below the ball milling chamber (8), and the discharge pipe (12) is arranged below the processing tower; The vacuum adsorption device (14) comprises an octadecane feed port (17), a silica aerogel powder feed port (18) and a loaded product outlet (19); the loaded product outlet (19) of the vacuum adsorption device (14) is connected to an input end of a loaded product storage tank (16) via a pipeline; The feed pipe (12) is connected to the input end of the silica aerogel micropowder storage tank (13), the output end of the silica aerogel micropowder storage tank (13) is connected to the silica aerogel micropowder feed port (18) of the vacuum adsorption device (14) via a pipeline, and the octadecane feed port (17) of the vacuum adsorption device (14) is connected to the octadecane storage tank (15) via a pipeline.

2. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: A reflux port (20) is provided on one side of the sieve plate chamber (11), and the reflux port (20) is connected to the raw material discharge port (1) via a pipeline.

3. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: A maintenance hole (5) is provided on one side of the crushing chamber (4).

4. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: The ball milling chamber (8) is provided with grinding beads (9) inside, and a plurality of grinding beads (9) are provided.

5. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: Four of the coarse material discharge ports (6) and the ball mill feed ports (7) are provided, and the four coarse material discharge ports (6) correspond to the four ball mill feed ports (7) in a one-to-one manner.

6. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: The silicon dioxide aerogel powder feeding ports (10) are provided with four.

7. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: A heating jacket is provided on the outside of the crushing chamber (4).

8. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: A sieve plate layer is arranged inside the sieve plate chamber (11), and the sieve plate layer of the sieve plate chamber (11) is provided with four layers of sieve plates.

9. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 8, characterized in that: The sieve plate layers of the sieve plate chamber (11) are, from bottom to top, 12500 mesh sieve plates, 8000 mesh sieve plates, 6250 mesh sieve plates and 5000 mesh sieve plates.

10. The process for preparing a silica aerogel integrated ball milling and vacuum adsorption phase change material according to claim 1, characterized in that: A powder delivery pump is provided on the pipeline connecting the silica aerogel powder storage tank (13) and the vacuum adsorption device (14), and a phase-changing material delivery pump is provided on the pipeline connecting the vacuum adsorption device (14) and the octadecane storage tank (15).

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