High-vacuum evaporation device suitable for evaporation desublimation system
By designing a high-vacuum evaporation device and combining it with modular temperature zone control and a film scraping mechanism, the contradiction between high vacuum and low pressure loss in traditional thin-film evaporation equipment has been resolved, achieving an efficient and stable evaporation process and continuous production, which is suitable for the chemical, pharmaceutical and food industries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHONGQING MINHENG TECH CO LTD
- Filing Date
- 2025-05-21
- Publication Date
- 2026-04-21
AI Technical Summary
Traditional thin-film evaporation equipment suffers from a systemic contradiction between high vacuum and low pressure loss, resulting in low evaporation efficiency and equipment instability. It also makes it difficult to achieve continuous production of low-temperature and high-temperature evaporation, increasing equipment costs and the risk of material contamination.
The device employs a high-vacuum evaporation unit, designed with the evaporation cylinder and separation cylinder coaxially connected. The film scraping mechanism includes a cantilevered rotor film scraper, a spiral propulsion film scraper, and a conical double spiral pusher. Combined with modular temperature zone control and a silicon carbide coated evaporation surface, it achieves efficient gradient evaporation and gas-liquid separation.
It achieves low pressure loss evaporation in a high vacuum environment, improves evaporation efficiency and product quality, reduces equipment pressure loss, supports continuous production, and can handle high-viscosity materials, thereby improving evaporation efficiency and product yield.
Smart Images
Figure CN224141479U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of fine chemical separation and purification, specifically to a high-vacuum evaporation device suitable for evaporation and sublimation systems. Background Technology
[0002] In numerous fields such as chemical engineering, pharmaceuticals, and food processing, thin-film evaporators are widely used for the evaporation and concentration of materials due to their highly efficient heat and mass transfer performance. Traditional thin-film evaporators primarily utilize a rotating scraping mechanism to spread the material into a uniform thin film on the heated wall surface, allowing the material to contact the heating surface with a larger specific surface area, thereby accelerating the evaporation rate. Its working principle is as follows: after the material enters the evaporator through the inlet, it forms a thin film on the inner wall of the heating cylinder under the action of gravity and the rotating scraping mechanism. The heating medium heats the outer wall of the cylinder, and the heat is transferred to the material through the cylinder, causing the solvent in the material to evaporate rapidly. The vapor is then separated and discharged, and the concentrated material is discharged from the bottom outlet.
[0003] However, traditional thin-film evaporation equipment still faces significant technical bottlenecks in the field of high-efficiency evaporation. Firstly, there is a systemic contradiction between high vacuum and low pressure loss during vacuum evaporation. To improve evaporation efficiency and lower the boiling point of materials, especially when processing heat-sensitive materials, a high vacuum environment needs to be maintained to achieve low-temperature evaporation and ensure material quality. However, as the vacuum level increases, gas flow resistance increases, and pressure loss increases significantly, making it difficult for steam to be discharged smoothly, severely affecting the evaporation efficiency and stable operation of the equipment. Secondly, for materials requiring evaporation at different temperature stages (low and high), traditional processes typically place low-temperature evaporation and high-temperature evaporation in separate equipment. This operating mode not only increases equipment investment costs and floor space, but also makes material transfer between equipment cumbersome, prone to contamination, and unable to achieve continuous production, resulting in low overall production efficiency and failing to meet the large-scale, high-efficiency production needs of modern industry. Utility Model Content
[0004] The present invention aims to provide a high-vacuum evaporation device suitable for evaporation and sublimation systems, so as to solve the systemic contradiction between high vacuum and low pressure loss in the existing technology.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A high-vacuum evaporation device suitable for evaporation and sublimation systems includes an evaporation cylinder, with a separation cylinder coaxially connected to the upper end of the evaporation cylinder. The evaporation cylinder includes a straight evaporation zone and a conical discharge section connected to the bottom of the straight evaporation zone. The length-to-diameter ratio of the evaporation cylinder is 4.8:1, and a scraping film mechanism is provided inside the evaporation cylinder.
[0007] Preferably, as an improvement, the straight-section evaporation zone includes a primary evaporation zone and a high-temperature concentration zone. The bottom and top of the primary evaporation zone are respectively provided with a medium-temperature hot oil inlet and a medium-temperature hot oil outlet. The bottom and top of the high-temperature concentration zone are respectively provided with a high-temperature hot oil inlet and a high-temperature hot oil outlet. The bottom and top of the conical discharge section are also respectively provided with a high-temperature hot oil inlet and a high-temperature hot oil outlet. The film scraping mechanism includes a cantilever rotor film scraper located in the primary evaporation zone, a spiral propulsion film scraper located in the high-temperature concentration zone, a conical double-helix pusher located in the conical discharge section, and a rotating shaft located at the axis of the evaporation cylinder and the separation cylinder. The rotating shaft is connected to the motor through a reducer. The cantilever rotor film scraper, the spiral propulsion film scraper, and the conical double-helix pusher are connected to the rotating shaft through a film scraper bracket.
[0008] Preferably, as an improvement, the high-temperature concentration zone is provided with an evaporation surface coated with silicon carbide.
[0009] Preferably, as an improvement, the primary evaporation zone is connected to a feed inlet, and the feed inlet is connected to a twin-screw metering pump.
[0010] Preferably, as an improvement, the height ratio of the straight evaporation zone to the conical discharge zone is 5:1.
[0011] Preferably, as an improvement, the total height of the evaporator is 4800mm, the height of the straight evaporation zone is 4000mm, and the diameter of the evaporator is 1000mm.
[0012] The principles and beneficial effects of this solution are as follows:
[0013] 1. The evaporator adopts a length-to-diameter ratio of 4.8:1, which optimizes the internal space and fluid flow characteristics of the equipment. Compared with the conventional ratio, it can effectively reduce the pressure loss when the gas flows in the evaporator, creating conditions for achieving a high vacuum environment. At the same time, it also helps the material to form a good liquid film distribution in the cylinder, improving the heat and mass transfer efficiency.
[0014] The coaxial connection between the evaporator and the separation cylinder allows for direct gas-liquid separation of the steam generated during evaporation within the upper separation cylinder, reducing steam transport path and resistance and improving separation efficiency. The structural design of the straight evaporation zone and the conical discharge section facilitates orderly material flow within the evaporator. The straight section provides a stable evaporation space, while the conical discharge section promotes the collection and discharge of concentrated material. The scraping film mechanism evenly scrapes the material into a thin film, increasing the contact area between the material and the heating surface, enhancing the evaporation process, and improving evaporation efficiency.
[0015] 2. The direct-section evaporation zone is divided into a primary evaporation zone and a high-temperature concentration zone, and equipped with an independent hot oil circulation system to achieve modular temperature zone control, providing precise temperature control for different stages of material evaporation. The primary evaporation zone uses medium-temperature hot oil to ensure evaporation efficiency while preventing material deterioration due to excessive temperature, making it suitable for the initial evaporation of heat-sensitive materials. The high-temperature concentration zone utilizes high-temperature hot oil, forming a 30-50℃ temperature gradient with the primary evaporation zone, which can process high-viscosity concentrated materials, achieving deep concentration and realizing efficient gradient evaporation of materials.
[0016] In addition, different types of scraper blades are configured in different areas. The cantilever rotor scraper blade can quickly and uniformly form a film on the material in the primary evaporation zone, and achieves more than 80% initial evaporation of the material in combination with medium-temperature hot oil. The spiral propulsion scraper blade can not only push the high-viscosity material forward in the high-temperature concentration zone, but also continuously renew the liquid film to prevent local overheating and coking of the material.
[0017] 3. The high-temperature concentration zone utilizes an evaporation surface coated with silicon carbide. This coating boasts high hardness, strong wear resistance, and excellent chemical stability, effectively resisting wear and corrosion from high-viscosity materials during scraping and evaporation, thus extending equipment lifespan. Simultaneously, silicon carbide exhibits excellent thermal conductivity, rapidly transferring heat to the material and improving the heat transfer efficiency of the high-temperature concentration zone. Combined with high-temperature hot oil and a spiral-propelled scraper, it can better handle concentrated materials with viscosities up to 5000 cP, ensuring uniform heating of the material under high-temperature conditions and preventing localized overheating that could lead to material deterioration or coking, thereby ensuring effective evaporation and concentration and product quality.
[0018] 4. The primary evaporation zone uses a twin-screw metering pump for feeding. This pump precisely controls the material feed rate with an accuracy of ±1.5%, ensuring a stable material flow rate into the primary evaporation zone and preventing fluctuations in feed from affecting the evaporation effect. This stable feed rate allows the material to form a uniform liquid film in the primary evaporation zone. Working in conjunction with the cantilevered rotor scraper and the medium-temperature hot oil circulation system, this achieves over 80% initial evaporation of the material, improving evaporation efficiency and process stability. It also lays the foundation for stable operation in the subsequent high-temperature concentration zone, ensuring continuous and efficient production of the entire unit.
[0019] 5. The height ratio of the straight evaporation zone to the conical discharge section is 5:1. This height ratio design provides ample space in the straight evaporation zone for material evaporation, ensuring sufficient residence time for the material in the primary evaporation zone and high-temperature concentration zone, fully completing the evaporation process and improving evaporation efficiency and concentration. The height of the conical discharge section ensures that the concentrated material smoothly converges at the discharge port without being too long, preventing material deterioration or blockage due to excessive residence time. Combined with the conical double-helix pusher, it enables continuous and smooth discharge of residue, ensuring the continuity and efficiency of the entire evaporation process, while also facilitating equipment cleaning and maintenance. Attached Figure Description
[0020] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model. Detailed Implementation
[0021] The following detailed description illustrates the specific implementation method:
[0022] The reference numerals in the accompanying drawings include: 1. Motor; 2. Reducer; 3. Reducer base; 4. Separator cylinder; 5. Evaporator cylinder; 6. Scraper blade support; 7. Cantilever rotor scraper blade; 8. Rotary shaft; 9. Spiral propulsion scraper blade; 10. Conical double spiral pusher blade; 11. High-temperature hot oil inlet; 12. High-temperature hot oil outlet; 13. Medium-temperature hot oil inlet; 14. Medium-temperature hot oil outlet; 15. Primary evaporation zone A; 16. High-temperature concentration zone B; 17. Conical discharge section C.
[0023] Example:
[0024] like Figure 1 As shown, a high-vacuum evaporation device suitable for evaporation-sublimation systems includes an evaporation cylinder 5, with a separation cylinder 4 coaxially connected to the upper end of the evaporation cylinder 5. The evaporation cylinder 5 includes a straight evaporation zone and a conical discharge section C connected to the bottom of the straight evaporation zone. The straight evaporation zone includes a primary evaporation zone A and a high-temperature concentration zone B. The height ratio of the straight evaporation zone to the height of the conical discharge section C is 5:1. The length-to-diameter ratio of the evaporation cylinder 5 is 4.8:1, where the length-to-diameter ratio is the ratio of the total height of the evaporation cylinder 5 to its inner diameter, with the inner diameter based on the inner diameter of the straight evaporation zone. Specifically, in this embodiment, the total height of the evaporation cylinder 5 is 4800 mm, the height of the straight evaporation zone is 4000 mm, and the diameter of the evaporation cylinder 5 is 1000 mm.
[0025] The primary evaporation zone A is connected to a feed inlet, which is connected to a twin-screw metering pump for feeding. The high-temperature concentration zone B is equipped with an evaporation surface coated with silicon carbide, and its operating temperature gradient with the primary evaporation zone A reaches 30-50℃, enabling it to process concentrated materials with viscosities up to 5000 cP. The primary evaporation zone A has a medium-temperature hot oil inlet 13 and a medium-temperature hot oil outlet 14 at its bottom and top, respectively. The high-temperature concentration zone B has a high-temperature hot oil inlet 11 and a high-temperature hot oil outlet 12 at its bottom and top, respectively. The conical discharge section C also has a high-temperature hot oil inlet 11 and a high-temperature hot oil outlet 12 at its bottom and top, respectively.
[0026] The evaporator 5 is equipped with a scraping film mechanism, which includes a cantilever rotor scraper 7 located in the primary evaporation zone A, a spiral propulsion scraper 9 located in the high-temperature concentration zone B, a conical double spiral pusher 10 located in the conical discharge section C, and a rotating shaft 8 located at the axis of the evaporator 5 and the separation cylinder 4. The rotating shaft 8 is connected to the motor 1 through a reducer 2. The reducer 2 is mounted on the top of the separation cylinder 4 through a reducer base 3. The cantilever rotor scraper 7, the spiral propulsion scraper 9, and the conical double spiral pusher 10 are connected to the rotating shaft 8 through a scraper bracket 6.
[0027] In practical applications, the twin-screw metering pump is turned on, and the feed rate is controlled with a high precision of ±1.5% according to production needs. The material is smoothly conveyed to the primary evaporation zone A through the feed inlet. During this process, the twin-screw metering pump continuously and stably pumps the material in, ensuring that the material flow rate entering the primary evaporation zone A is uniform and stable.
[0028] After the material enters the primary evaporation zone A, the cantilevered rotor scraper 7 rotates at high speed driven by the rotating shaft 8, quickly and evenly coating the material onto the inner wall of the evaporation cylinder 5, forming a thin and uniform liquid film. Medium-temperature hot oil flows in from the medium-temperature hot oil inlet 13 at the bottom of the primary evaporation zone A, circulating outside the cylinder wall. Through heat conduction, it transfers heat to the liquid film on the inner side of the cylinder wall, causing some of the solvent in the material to evaporate rapidly and form steam. At this stage, more than 80% of the material undergoes initial evaporation. The steam generated rises and enters the coaxially connected separation cylinder 4 above for gas-liquid separation, while the incompletely evaporated material remains in the primary evaporation zone A.
[0029] The material after primary evaporation flows downwards into the high-temperature concentration zone B. In this zone, the evaporation surface, coated with silicon carbide, combined with the high-temperature hot oil flowing in from the bottom high-temperature hot oil inlet 11 and out from the top high-temperature hot oil outlet 12, creates a temperature gradient environment of 30-50°C (compared to the temperature of the primary evaporation zone A). Driven by the rotating shaft 8, the spiral-propelled scraper blade 9 further scrapes the material into a thin film while simultaneously pushing the high-viscosity material forward along the inner wall of the evaporation cylinder 5. Under the combined action of high temperature and scraping, the remaining solvent in the material continues to evaporate, completing deep concentration. This effectively handles concentrated materials with viscosities as high as 5000 cP, preventing localized overheating and coking. The steam generated in this process also rises to the separation cylinder 4 for separation.
[0030] After high-temperature concentration, the residue enters the conical discharge section C. The high-temperature hot oil circulation system in this area maintains a certain temperature to prevent the residue from clogging due to cooling and solidification. Driven by the rotating shaft 8, the conical double-helix pusher continuously pushes the residue out from the bottom of the conical discharge section C.
[0031] This solution, through a specific length-to-diameter ratio of the evaporator 5 and the height ratio of the straight evaporation zone to the conical discharge section C, combined with a modular temperature zone design and the synergistic effect of different types of scraping film mechanisms, significantly reduces axial pressure loss, achieving highly efficient gradient evaporation of materials. It not only successfully overcomes the technical paradox of high vacuum and low pressure loss but also enables continuous production, reducing axial pressure loss to below 35% of traditional equipment. Simultaneously, it can handle materials with viscosities up to 5000 cP, significantly improving evaporation efficiency and product quality. Verification shows that this solution achieves an evaporation efficiency of 38 kg / (m³) under vacuum conditions ≤100 Pa. 2 The process efficiency is 240% higher than traditional equipment; the product yield exceeds the critical value of 95% (determined by ASTM D86 method), and the residue after evaporation is ≤5%. The specially designed short-path structure controls the material residence time to 45-90s, effectively avoiding thermal decomposition problems.
[0032] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. A high vacuum evaporation device suitable for use in a desublimation system, characterized in that: It includes an evaporator, with a separation cylinder coaxially connected to the upper end of the evaporator. The evaporator includes a straight evaporation zone and a conical discharge section connected to the bottom of the straight evaporation zone. The length-to-diameter ratio of the evaporator is 4.8:1, and a scraping film mechanism is provided inside the evaporator.
2. A high vacuum evaporation device suitable for use in a vapor deposition desublimation system according to claim 1, characterized in that: The direct-section evaporation zone includes a primary evaporation zone and a high-temperature concentration zone. The primary evaporation zone has a medium-temperature hot oil inlet and a medium-temperature hot oil outlet at its bottom and top, respectively. The high-temperature concentration zone has a high-temperature hot oil inlet and a high-temperature hot oil outlet at its bottom and top, respectively. The conical discharge section also has a high-temperature hot oil inlet and a high-temperature hot oil outlet at its bottom and top, respectively. The scraping mechanism includes a cantilever rotor scraper in the primary evaporation zone, a spiral propulsion scraper in the high-temperature concentration zone, a conical double-spiral pusher in the conical discharge section, and a rotating shaft located at the axis of the evaporation cylinder and the separation cylinder. The rotating shaft is connected to the motor through a reducer. The cantilever rotor scraper, the spiral propulsion scraper, and the conical double-spiral pusher are connected to the rotating shaft through a scraper bracket.
3. A high vacuum evaporation device suitable for use in a vapor deposition desublimation system according to claim 2, characterized in that: The high-temperature concentration zone is equipped with an evaporation surface coated with silicon carbide.
4. A high vacuum evaporation device suitable for use in an evaporative desiccant system according to claim 3, characterized in that: The primary evaporation zone is connected to a feed inlet, which is connected to a twin-screw metering pump.
5. A high vacuum evaporation device suitable for use in a vapor deposition desublimation system according to claim 4, characterized in that: The ratio of the height of the straight evaporation zone to the height of the conical discharge zone is 5:
1.
6. A high vacuum evaporation device suitable for use in a vapor deposition desublimation system according to claim 5, characterized in that: The total height of the evaporator is 4800mm, the height of the straight evaporation zone is 4000mm, and the diameter of the evaporator is 1000mm.