Ultralow volatile component silicone oil atomization low component removal device and low component removal process

Abstract

The invention discloses an ultra-low volatile silicone oil atomization low-content removal device and a low-content removal process. The rear part of the preheater is connected with a feeding hole in the side part of the low-component removal equipment, a discharging hole is formed in the bottom of the low-component removal equipment and is connected with the heavy component tank, and a light component outlet is formed in the bottom of the low-component removal equipment and is connected with the light component tank. The preheated low-viscosity silicone oil is pressed into low-component removal equipment and forms fine fog drops through a nozzle to fall down, low molecules in the fog drops are extremely volatile in a vacuum environment, and the volatile low molecules pass through holes of a tubesheet, then encounter a condensation pipe and are immediately condensed into liquid to be collected in a light-component tank; and the residual non-condensable gas passes through a gas phase outlet and then is cooled in a cold trap to reduce the air pressure so as to ensure the vacuum degree, and fog drops remained in the low-content removal equipment are collected into a heavy component tank at the bottom. By means of the atomization technology, the energy consumption problem in silicone oil low-content removal is solved, the volatile matter content in the silicone oil is smaller than or equal to 1.00% (200 DEG C * 4 h), and the silicone oil with the ultralow volatile matter content is prepared.

Description

Technical Field

[0001] The invention relates to the field of silicone oil desulfurization, and specifically relates to an ultra-low volatile silicone oil atomization desulfurization device and a desulfurization process. Background Art

[0002] Silicone oil is usually made of octamethylcyclotetrasiloxane (D4), hexamethylcyclotrisiloxane (D3) or cyclosiloxane mixture (DMC) as the main body, with the addition of a capping agent (such as hexamethyldisiloxane, tetramethyldivinyldisiloxane, etc.), and is polymerized under acid / base conditions and low molecular weight is removed.

[0003] With the expansion of application fields and the upgrading of products, the market has higher and higher requirements for the quality of silicone oil, and volatile matter is the most basic and important quality indicator of silicone oil. The volatile matter in silicone oil has a great impact on products in the fields of aerospace, electronic glue, medical glue, etc. For example, in the field of chip semiconductors, customers' requirements for silicone oil volatile matter have increased from 0.5% (200℃*4h) to 0.3% (200℃*4h). Regarding the volatile matter of silicone oil, the current silicone oil degassing process on the market has gradually changed from single-pot high-temperature vacuum degassing to thin-film evaporator degassing. If the volatile matter of silicone oil needs to be further reduced, it will pass through a short-path distiller again. This degassing technology has a certain improvement in the volatile matter of silicone oil, but the energy consumption and efficiency are relatively unsatisfactory. The current market situation of organic silicon is sluggish, and it is urgently needed to reduce costs and increase efficiency in the industry. Therefore, the silicone oil degassing technology needs to be improved. Summary of the invention

[0004] In order to produce ultra-low volatility silicone oil, the present invention provides an ultra-low volatility silicone oil atomization degassing device and a degassing process.

[0005] The dehydration device comprises a preheater, dehydration equipment, a heavy component tank, a light component tank, a cold trap and a vacuum system; the rear of the preheater is connected to a feed port on the side of the dehydration equipment, a discharge port is provided at the bottom of the dehydration equipment, the discharge port is connected to the heavy component tank, a light component outlet is provided at the bottom of the dehydration equipment, and the light component outlet is connected to the light component tank.

[0006] Furthermore, the feed port of the degassing equipment is connected to a distribution pipe, and a plurality of nozzles are provided on the distribution pipe, and the angle of the nozzles is 90° to 120°.

[0007] Furthermore, the de-lowering equipment is provided with a condenser, and the condenser has a cold water inlet and a cold water outlet. Each condenser has flower plates on both sides, and the lowest point of the area between the flower plates is connected to the light component outlet.

[0008] Furthermore, a gas phase outlet is provided on the side of the degassing equipment, the gas phase outlet is connected to a cold trap, a discharge port at the bottom of the cold trap is connected to a light component tank, and the gas phase outlet of the cold trap is connected to a vacuum system.

[0009] Furthermore, the cold trap has a chilled water inlet and a chilled water outlet, into which -15 to -5°C chilled water is introduced.

[0010] In the technical solution of the present invention, a preheater is connected to a feed port on the side of a de-mineralization device, the feed port is connected to a distribution pipe, a plurality of nozzles are arranged on the distribution pipe, and the silicone oil can be sprayed out in a mist form. A heavy component discharge port is arranged at the bottom of the spray area, and the heavy component discharge port is connected to a heavy component tank. A condenser is arranged in the de-mineralization device, and each condenser has flower plates on both sides. The lowest point of the area between the flower plates is connected to a light component discharge port, and the light component discharge port is connected to a light component tank. A gas phase outlet is arranged on the side of the de-mineralization device, and the gas phase outlet is connected to a cold trap. The discharge port at the bottom of the cold trap is connected to the light component tank, and the gas phase outlet of the cold trap is connected to a vacuum system. The preheated low-viscosity silicone oil is pressed into the degassing equipment and falls down through the nozzle to form fine droplets. In a vacuum environment, the low molecules in the droplets are very easy to volatilize. After passing through the holes in the flower plate and encountering the condenser, the volatilized low molecules immediately condense into liquid and are collected in the light component tank. The remaining non-condensable gas passes through the gas phase outlet and is cooled in the cold trap to reduce the air pressure to ensure the vacuum degree. The droplets remaining in the degassing equipment are collected in the heavy component tank at the bottom. Through atomization technology, the energy consumption problem in silicone oil degassing can be greatly reduced, and the quality of silicone oil can be further improved.

[0011] The present invention also provides a process for atomizing and degassing ultra-low volatile silicone oil using the above-mentioned degassing device: (1) Silicone oil preheating: Preheat the low-viscosity silicone oil and let it enter the distribution pipe; (2) Degassing: After preheating, low-viscosity silicone oil is sprayed out from the nozzle in the distribution pipe, forming mist oil droplets in the degassing equipment. Under high temperature and high vacuum conditions, the gaseous low molecular weight in the oil droplets evaporates, and the oil droplets flow into the heavy component tank from the bottom outlet of the degassing equipment.

[0012] In the step (1), the low-viscosity silicone oil is preheated to a temperature of 130 to 220°C.

[0013] In the step (2), the nozzles are in groups of 2 to 10, the particle size of the mist oil droplets produced by the nozzles is 2 to 10 μm, and the flow rate sprayed from the nozzles is 140 to 200 kg / h.

[0014] In the step (2), the vacuum degree in the degassing equipment is 10-50 Pa; the material temperature is 140-240°C.

[0015] The de-lowering process of the present invention also includes the treatment process of the low-molecular system: the volatilized gaseous low-molecular substances pass through the flower plate, meet the condenser tube, condense into liquid, and then flow into the light component tank from the bottom of the de-lowering equipment; the remaining high-temperature non-condensable gas passes through the gas phase tube and enters the cold trap for cooling to reduce the absolute pressure and ensure high vacuum. 10-20℃ circulating water is introduced into the condenser tube, and -15--5℃ chilled water is introduced into the cold trap.

[0016] During the desulfurization process of silicone oil, small molecular weight siloxane rings and short chains will be removed. The larger the molecular weight, the higher the boiling point, and the more difficult it is to remove. After conventional desulfurization methods, some small molecular weight siloxane rings and short chains are removed, but there are still siloxane rings and short chains that cannot be removed by this method. These siloxanes have relatively larger molecular weights and higher boiling points.

[0017] The present invention disperses silicone oil into oil droplets through a nozzle to increase the specific surface area of ​​the silicone oil. Secondly, the gaseous low-molecular substances just removed are quickly condensed into liquid through a built-in condenser in the degassing equipment, and the high-temperature non-condensable gas is cooled through a cold trap to reduce the air pressure to form a high vacuum. Thirdly, the degassing equipment itself does not need to pass heat transfer oil or a motor, thereby saving energy and reducing consumption. Finally, the volatile matter in the silicone oil can be ≤2.00% (200℃*4h), more preferably ≤1.0% (200℃*4h), and more preferably ≤0.10% (200℃*4h), so as to obtain ultra-low volatility silicone oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the device of the present invention.

[0019] Figure 2 It is a schematic diagram of the structure inside the lowering device.

[0020] Figure 3 Schematic diagram of the spray structure.

[0021] In the figure: 1. preheater; 2. degassing device; 3. heavy component tank; 4. light component tank; 5. cold trap; 6. vacuum system; 7. distribution pipe; 8. nozzle; 9. condenser; 10. flower plate; N1. feed inlet; N2. discharge port; N3. light component outlet; N4. gas phase outlet; N5. cold trap discharge port; N6. cold trap gas phase outlet; N7. cold water inlet; N8 cold water outlet; N9. chilled water inlet; N10. chilled water outlet. DETAILED DESCRIPTION

[0022] The following is a further detailed description of the embodiments of the present invention by means of examples and in conjunction with the accompanying drawings.

[0023] Example 1 A device for atomizing and removing ultra-low volatile silicone oil. The device comprises a preheater 1, a degassing device 2, a heavy component tank 3, a light component tank 4, a cold trap 5, and a vacuum system 6; characterized in that the preheater 1 is connected to a feed inlet N1 on the side of the degassing device 2, a discharge port N2 is provided at the bottom of the degassing device 2, and the discharge port N2 is connected to the heavy component tank 3, and a light component outlet N3 is provided at the bottom of the degassing device 2, and the light component outlet N3 is connected to the light component tank 4.

[0024] The feed port N1 of the de-lowering device 2 is connected to the distribution pipe 7, and the distribution pipe 7 is provided with 6 nozzles 8, and the nozzle angle is 90°.

[0025] The denitrification equipment 2 is provided with a condenser 9, and the condenser has a cold water inlet N7 and a cold water outlet N8. Each condenser 9 has flower plates 10 on both sides, and the lowest point of the area between the flower plates 10 is connected to the light component outlet N3.

[0026] The side of the denitrification equipment 2 is provided with a gas phase outlet N4, which is connected to the cold trap 5, the bottom discharge port N5 of the cold trap 5 is connected to the light component tank, and the gas phase outlet N6 of the cold trap 5 is connected to the vacuum system 6.

[0027] The cold trap has a chilled water inlet N9 and a chilled water outlet N10.

[0028] Example 2 A process for atomizing and removing ultra-low volatile silicone oil, using the device of Example 1, the silicone oil with a volatile content of 1.36% is preheated to 160°C by the preheater 1 and then enters the removal device 2, and is sprayed from each nozzle 8 through the distribution pipe 7 at a flow rate of 160kg / h to form 90° fan-shaped mist oil droplets with a particle size of 6μm. Under the action of the vacuum system 6, the system vacuum degree is 30Pa, the light components in the oil mist are volatilized and immediately pass through the flower plate 10 to meet the condenser 9 to condense into liquid, and flow into the light component tank 4 from the bottom, and the cold water temperature in the condenser is 10-20°C. The volatilized non-condensable gas reaches the cold trap 5 through the gas phase outlet N4 and is cooled and then enters the vacuum system 6, and the temperature of the chilled water in the cold trap is -10 to -5°C. The non-volatile heavy components in the oil mist are collected in the heavy component tank 3 through the discharge port N2.

[0029] Detection of heavy component volatiles: Keep the silicone oil at a constant temperature of 25±0.5℃ for 2h, take 2±0.1g and drop it into a drying dish to accurately weigh the sample weight (accurate to 0.1mg), put the drying dish into a forced air drying oven at 200±5℃ and keep it ventilated, take it out after 4h and put it into a desiccator to cool to room temperature, weigh it, and calculate the percentage of volatile matter based on the weight difference.

[0030] Example 3 The operation steps were the same as those in Example 2a, except that the initial silicone oil in Example 2 was adjusted to 0.75%.

[0031] Example 4 The operation steps were the same as those in Example 2a, except that the initial silicone oil in Example 2 was adjusted to 1.85%.

[0032] Comparative Example 5 The operation steps were the same as those in Example 2a, except that the initial silicone oil in Example 2 was adjusted to 2.53%.

[0033] Comparative Example 6 The operation steps were the same as those in Example 2a, except that the initial silicone oil in Example 2 was adjusted to 3.02%.

[0034] The results of the detection of volatile components of silicone oil in Examples 2 to 4 and Comparative Examples 5 and 6 are shown in Table 1.

[0035] Table 1 Effect of initial volatile matter of silicone oil on volatile matter after treatment

[0036] Example 7 The operation steps are the same as those in Example 2, except that the particle size of the silicone oil sprayed from the nozzle in Example 2 is adjusted to 2 μm.

[0037] Example 8 The operation steps are the same as those in Example 2, except that the particle size of the silicone oil sprayed from the nozzle in Example 2 is adjusted to 10 μm.

[0038] Comparative Example 9 The operation steps are the same as those in Example 2, except that the particle size of the silicone oil sprayed from the nozzle in Example 2 is adjusted to 15 μm.

[0039] Comparative Example 10 The operation steps are the same as those in Example 2, except that the particle size of the silicone oil sprayed from the nozzle in Example 2 is adjusted to 25 μm.

[0040] The results of the detection of volatile components of silicone oil in Examples 2, 7, 8 and Comparative Examples 9 and 10 are shown in Table 2.

[0041] Table 2 Effect of nozzle sprayed silicone oil particle size on volatile matter

[0042] Comparative Example 11 The operation steps are the same as those in Example 2, except that the spraying angle of the nozzle in Example 2 is adjusted to 30°.

[0043] Comparative Example 12 The operation steps are the same as those in Example 2, except that the spraying angle of the nozzle in Example 2 is adjusted to 60°.

[0044] Example 13 The operation steps are the same as those in Example 2, except that the spraying angle of the nozzle in Example 2 is adjusted to 120°.

[0045] The results of the detection of volatile components of silicone oil in Examples 2 and 13 and Comparative Examples 11 and 12 are shown in Table 3.

[0046] Table 3 Effect of nozzle spray angle on volatile matter

[0047] Comparative Example 14 The operation steps are the same as those in Example 2, except that the vacuum degree in Example 2 is adjusted to 10 Pa.

[0048] Comparative Example 15 The operating steps are the same as those in Example 2, except that the vacuum degree in Example 2 is adjusted to 50 Pa.

[0049] Comparative Example 16 The operating steps are the same as those in Example 2, except that the vacuum degree in Example 2 is adjusted to 70 Pa.

[0050] Comparative Example 17 The operation steps are the same as those in Example 2, except that the vacuum degree in Example 2 is adjusted to 100 Pa.

[0051] The results of the detection of volatile components of silicone oil in Examples 2, 14, 15 and Comparative Examples 16 and 17 are shown in Table 4.

[0052] Table 4 Effect of vacuum degree on volatile matter

[0053] Comparative Example 18 The operation steps are the same as those of Example 2a, except that the temperature of the chilled water introduced into the cold trap in Example 2 is adjusted to -20 to -15°C.

[0054] Embodiment 19 The operation steps are the same as those of Example 2a, except that the temperature of the chilled water introduced into the cold trap in Example 2 is adjusted to -15 to -10°C.

[0055] Comparative Example 20 The operation steps are the same as those of Example 2a, except that the temperature of the chilled water introduced into the cold trap in Example 2 is adjusted to -5 to 0°C.

[0056] Comparative Example 21 The operation steps are the same as those of Example 2a, except that the temperature of the chilled water introduced into the cold trap in Example 2 is adjusted to 0-10°C.

[0057] Comparative Example 22 The operation steps are the same as those of Example 2a, except that the temperature of the chilled water introduced into the cold trap in Example 2 is adjusted to 10-20°C.

[0058] The results of the detection of volatile components of silicone oil in Examples 2 and 19 and Comparative Examples 18, 20 to 22 are shown in Table 5.

[0059] Table 5 Effect of chilled water temperature on volatile matter

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An ultra-low volatility silicone oil atomization degassing device, the degassing device comprising a preheater (1), a degassing device (2), a heavy component tank (3), a light component tank (4), a cold trap (5), and a vacuum system (6); characterized in that: The preheater (1) is connected to a feed port (N1) on the side of a degassing device (2) at the rear, a discharge port (N2) is provided at the bottom of the degassing device (2), the discharge port (N2) is connected to a heavy component tank (3), a light component outlet (N3) is provided at the bottom of the degassing device (2), and the light component outlet (N3) is connected to a light component tank (4).

2. The ultra-low volatility silicone oil atomization and degassing device according to claim 1, characterized in that: The feed inlet (N1) of the degassing device (2) is connected to a distribution pipe (7), and a plurality of nozzles (8) are provided on the distribution pipe (7), and the angle of the nozzles is 90° to 120°.

3. The ultra-low volatility silicone oil atomization and degassing device according to claim 1, characterized in that: The desulfurization device (2) is provided with a condenser (9), the condenser having a cold water inlet (N7) and a cold water outlet (N8), each condenser (9) having flower plates (10) on both sides, and the lowest point of the area between the flower plates (10) is connected to the light component outlet (N3).

4. The ultra-low volatility silicone oil atomization and degassing device according to claim 1, characterized in that: A gas phase outlet (N4) is provided on the side of the degassing device (2), the gas phase outlet (N4) is connected to the cold trap (5), the bottom discharge port (N5) of the cold trap (5) is connected to the light component tank, and the gas phase outlet (N6) of the cold trap (5) is connected to the vacuum system (6).

5. The ultra-low volatility silicone oil atomization and degassing device according to claim 1, characterized in that: The cold trap has a chilled water inlet (N9) and a chilled water outlet (N10), into which -15 to -5°C chilled water is introduced.

6. The ultra-low volatility silicone oil atomization degassing process according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Silicone oil preheating: Preheat the low-viscosity silicone oil and let it enter the distribution pipe; (2) Degassing: After preheating, low-viscosity silicone oil is sprayed out from the nozzle in the distribution pipe, forming mist oil droplets in the degassing equipment. Under high temperature and high vacuum conditions, the gaseous low molecular weight in the oil droplets evaporates, and the oil droplets flow into the heavy component tank from the bottom outlet of the degassing equipment.

7. The ultra-low volatility silicone oil atomization degassing process according to claim 6, characterized in that: In the step (1), the low-viscosity silicone oil is preheated to a temperature of 130 to 220°C.

8. The ultra-low volatility silicone oil atomization degassing process according to claim 6, characterized in that: In the step (2), the nozzles are in groups of 2 to 10, the particle size of the mist oil droplets produced by the nozzles is 2 to 10 μm, and the flow rate sprayed from the nozzles is 140 to 200 kg / h.

9. The ultra-low volatility silicone oil atomization degassing process according to claim 6, characterized in that: In the step (2), the vacuum degree in the degassing equipment is 10-50 Pa; the material temperature is 140-240°C.

10. The ultra-low volatility silicone oil atomization degassing process according to claim 6, characterized in that: In the step (2), the volatilized gaseous low molecular weight substances pass through the flower plate and encounter the condenser tube to be condensed into liquid, and then flow into the light component tank from the bottom of the denitrification equipment; the condenser tube is connected to circulating water at 10 to 20°C.

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