Ethylene glycol monomethyl ether and water melt crystallization separation device

Abstract

The utility model provides an ethylene glycol monomethyl ether and water melt crystallization separation device which comprises a melt crystallizer which is provided with a feeding pipe, a crystal slurry outlet, a vertical pipe bundle module consisting of a crystallization pipe, an upper end plate and a lower end plate, a water distribution system comprising an annular liquid distribution pipe and a liquid distribution branch pipe, and a crystallization strengthening unit comprising a spiral flow deflector and a super-hydrophobic nano groove, the spiral flow deflector enables mixed liquid to form a rotational flow falling film, the super-hydrophobic nano groove optimizes the crystallization environment, and the spiral flow deflector and the super-hydrophobic nano groove synergistically improve the crystallization efficiency. The device realizes efficient separation, is energy-saving and environment-friendly, has a stable and durable structure, can meet the purification requirement of ethylene glycol monomethyl ether, and improves the product quality and the production benefit.

Description

Technical Field

[0001] This utility model relates to the field of melt crystallization separation technology, and more specifically, to a device for melt crystallization separation of ethylene glycol methyl ether and water. Background Technology

[0002] Ethylene glycol methyl ether (EDGME) is an important organic solvent and chemical raw material widely used in industries such as coatings, inks, and electronic chemicals. However, during its production or use, it often forms a mixture with water, requiring separation and purification to meet the quality requirements of different production stages.

[0003] Currently, the main methods for separating ethylene glycol methyl ether from water include distillation and extraction, but these traditional methods have certain limitations. Distillation requires a large amount of energy for heating and cooling, resulting in high separation costs, and it is not effective for some azeotropic mixtures. Extraction requires specific extractants, which not only increases production costs but may also introduce new impurities and complicates subsequent processing.

[0004] With increasingly stringent environmental protection and energy conservation requirements, melt crystallization separation technology has gained growing attention. Melt crystallization utilizes the differences in solubility of components in a mixture at different temperatures, controlling the temperature to induce the crystallization of the target component, thereby achieving separation. However, existing melt crystallization separation devices suffer from low crystallization efficiency and poor separation effects when applied to the separation of ethylene glycol methyl ether and water. For example, uneven distribution of the mixture within the crystallization tube prevents sufficient crystallization; the wettability of the inner wall of the crystallization tube affects the formation of crystal nuclei and crystal growth, reducing separation efficiency. Utility Model Content

[0005] Based on the above-mentioned technical problems, this utility model proposes a device for separating ethylene glycol methyl ether and water by melting and crystallization.

[0006] An apparatus for separating ethylene glycol methyl ether from water by melt crystallization includes:

[0007] A melting crystallizer, which has a feed pipe at the top and a crystal slurry outlet at the bottom;

[0008] The vertical tube bundle module consists of multiple parallel crystallizing tubes, with the upper and lower ends of each tube fixed to an upper end plate and a lower end plate, respectively. The end plates are sealed to the inner wall of the crystallizer.

[0009] The water distribution system is located above the upper end plate and includes a liquid distribution branch pipe connected to the feed pipe.

[0010] Crystallization strengthening unit, comprising:

[0011] The spiral guide vanes installed at the upper end of each crystallizer tube have a pitch P that satisfies the tube diameter D as follows: 0.2≤P / D≤0.5, so that the mixture forms a swirling falling film.

[0012] Axially extending superhydrophobic nanogrooves are formed on the inner wall of the crystallization tube, with a groove depth H = 0.1-1 mm and a surface contact angle θ ≥ 150°.

[0013] The spiral lead of the trench is consistent with the lead of the guide plate, and the surface of the trench is formed by plasma etching to form a nanoscale rough structure.

[0014] Furthermore, the inlet tilt angle α of the spiral guide vane satisfies: 15°≤α≤35°;

[0015] The ratio of the area S of the upper port of the flow guide plate to the area S of the crystallizer tube satisfies: 0.3≤S≤0.6.

[0016] Furthermore, the width W and depth H of the superhydrophobic nanogroove satisfy: 0.8≤W / H≤1.5;

[0017] The spacing between adjacent trenches is δ=10-100μm, and the trenches are loaded with fluoropolymer coatings.

[0018] Beneficial effects:

[0019] 1. High-efficiency crystallization and separation: Through the uniform liquid distribution of the water distribution system, and the synergistic effect of the swirling falling film formed by the spiral guide plate in the crystallization enhancement unit and the superhydrophobic nanogrooves, the mixed liquid can achieve uniform distribution and high-efficiency crystallization in the crystallization tube. The swirling falling film increases the contact area and time between the mixed liquid and the inner wall of the crystallization tube, and the superhydrophobic nanogrooves reduce the wettability of the liquid and promote crystal precipitation, thereby improving the separation efficiency and purity of ethylene glycol methyl ether and water, and obtaining high-quality ethylene glycol methyl ether products;

[0020] 2. Energy saving and environmental protection: Compared with traditional separation methods such as distillation, melt crystallization separation technology itself has the advantage of energy saving. This device further improves the efficiency of crystallization separation and reduces energy consumption through optimized structural design.

[0021] 3. Stable and durable structure: The materials and structures of components such as crystallizer tubes, spiral guide vanes and superhydrophobic nanogrooves have been optimized, resulting in good stability and durability. The plasma etching and fluoropolymer coating treatment on the surface of the superhydrophobic nanogrooves improves their wear resistance and corrosion resistance, ensuring long-term stable operation of the device and reducing equipment maintenance costs. Attached Figure Description

[0022] Figure 1 A schematic diagram of the structure of this utility model is shown;

[0023] Figure 2A schematic diagram of the internal structure of this utility model is shown;

[0024] Figure 3 A schematic diagram of the spiral guide vane is shown.

[0025] Figure 4 A schematic diagram of the trench structure of this utility model is shown;

[0026] In the attached diagram, 10 is the melt crystallizer, 11 is the feed pipe, 12 is the crystal slurry outlet, 20 is the crystallization tube, 21 is the upper end plate, 22 is the lower end plate, 30 is the water distribution system, 31 is the liquid distribution branch pipe, 40 is the spiral guide vane, and 50 is the groove. Detailed Implementation

[0027] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0028] like Figures 1-4 The apparatus shown is a melting crystallization separation device for ethylene glycol methyl ether and water, which consists of a melting crystallizer 10, a vertical tube bundle module, a water distribution system 30, and a crystallization enhancement unit.

[0029] The melt crystallizer 10 is equipped with a feed pipe 11 at the top for feeding a mixture of ethylene glycol methyl ether and water into the device; and a crystal slurry outlet 12 at the bottom for discharging the crystal slurry after crystallization separation. The melt crystallizer 10 provides a closed space environment for the crystallization separation of the mixture. It is also equipped with a water inlet pipe 14 and a water outlet pipe 13 at the top and bottom, which are connected to the inside of the melt crystallizer 10 and connected to the external temperature regulation equipment.

[0030] The vertical tube bundle module consists of multiple parallel crystallization tubes 20. The upper and lower ends of each crystallization tube 20 are fixed to the upper end plate 21 and the lower end plate 22, respectively. The end plates are sealed to the inner wall of the crystallizer. The crystallization tubes 20 are the main places for the crystallization and separation of the mixture. The arrangement of multiple crystallization tubes 20 increases the surface area for crystallization and improves the crystallization efficiency. The upper end plate 21 and the lower end plate 22 serve to fix and support the crystallization tubes 20, while ensuring the sealing of the crystallizer and preventing leakage of the mixture.

[0031] The water distribution system 30 is located above the upper end plate 21 and includes a liquid distribution branch pipe 31 connected to the feed pipe 11. The mixed liquid input from the feed pipe 11 enters the liquid distribution branch pipe 31 and is evenly distributed to the upper port of each crystallization tube 20, ensuring that the mixed liquid can enter the crystallization tube 20 evenly, providing conditions for subsequent uniform crystallization.

[0032] Crystallization strengthening unit

[0033] Spiral guide vanes 40: Located at the upper port of each crystallizer tube 20, the spiral guide vanes 40 have a pitch P that satisfies the tube diameter D as follows: 0.2 ≤ P / D ≤ 0.5. When the mixture passes through the upper port of the crystallizer tube 20, the spiral guide vanes 40 cause the mixture to form a swirling falling film. The formation of this swirling falling film increases the contact area and contact time between the mixture and the inner wall of the crystallizer tube 20, promoting the formation of crystal nuclei and crystal growth. Simultaneously, the inlet inclination angle α of the spiral guide vanes 40 satisfies: 15° ≤ α ≤ 35°, and the area S covering the upper port of the crystallizer tube 20 by the guide vanes satisfies: 0.3 ≤ S ≤ 0.6. Optimizing these parameters further improves the effect of the swirling falling film, making the distribution of the mixture within the crystallizer tube 20 more uniform, which is beneficial for the crystallization process.

[0034] Superhydrophobic nanogrooves 50: Axially extending superhydrophobic nanogrooves 50 are provided on the inner wall of the crystallization tube 20. The depth of the groove 50 is H=0.1-1mm and the surface contact angle θ≥150°. The superhydrophobic surface can reduce the wettability of the mixture on the inner wall of the crystallization tube 20, so that the mixture flows in the form of a liquid film, reducing the residence and accumulation of liquid on the tube wall, and promoting the precipitation and growth of crystals. The spiral lead of the groove 50 is consistent with the lead of the guide plate. This design can make the swirling falling film match the structure of the groove 50, further enhancing the flow characteristics and crystallization effect of the mixture in the crystallization tube 20. Furthermore, the surface of the trench 50 is formed with a nanoscale rough structure by plasma etching, and the trench 50 is loaded with a fluoropolymer coating. These treatments can improve the stability and durability of the superhydrophobic properties and ensure the long-term effective operation of the crystallization strengthening unit. At the same time, the width W and depth H of the superhydrophobic nano-trench 50 satisfy: 0.8≤W / H≤1.5; the spacing between adjacent trenches 50 is δ=10-100μm. The optimized setting of these parameters can enable the trench 50 structure to play a better role and improve the crystallization efficiency and separation effect.

[0035] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A device for separating ethylene glycol methyl ether from water through melt crystallization, characterized in that, include: The melting crystallizer (10) has a feed pipe (11) at the top and a crystal slurry outlet (12) at the bottom. The vertical tube bundle module consists of multiple parallel crystallization tubes (20), with the upper and lower ends of each tube fixed to the upper end plate (21) and the lower end plate (22) respectively. The end plates are sealed to the inner wall of the crystallizer. The water distribution system (30) is located above the upper end plate (21) and includes a liquid distribution branch pipe (31) connected to the feed pipe (11). Crystallization strengthening unit, comprising: The spiral guide vanes (40) installed at the upper end of each crystallizer tube have a pitch P and a tube diameter D that satisfy: 0.2≤P / D≤0.5, so that the mixture forms a swirling falling film; An axially extending superhydrophobic nanogroove (50) is provided on the inner wall of the crystallization tube, with a groove depth H=0.1-1mm and a surface contact angle θ≥150°; The spiral lead of the groove (50) is consistent with the lead of the guide plate (40), and the surface of the groove is formed by plasma etching to form a nanoscale rough structure.

2. The apparatus for separating ethylene glycol methyl ether from water by melt crystallization according to claim 1, characterized in that, The inlet inclination angle α of the spiral guide vane (40) satisfies: 15°≤α≤35°; The ratio of the area S of the upper port of the flow guide plate to the area S of the crystallizer tube satisfies: 0.3≤S≤0.

6.

3. The apparatus for separating ethylene glycol methyl ether from water by melt crystallization according to claim 1, characterized in that, The width W and depth H of the superhydrophobic nanogroove (50) satisfy: 0.8≤W / H≤1.5; The spacing between adjacent trenches is δ=10-100μm, and the trenches are loaded with fluoropolymer coatings.

Images