Methyl methacrylate refining device

Abstract

The utility model belongs to the technical field of methyl methacrylate, and specifically relates to a methyl methacrylate refining device. It comprises a light-removing tower, the top outlet of which is connected to a separation tank through a first condenser, the gas phase outlet of the first condenser is connected to a first induced draft fan through a pipeline; the outlet of the separation tank is connected to an esterification unit through a pipeline; the bottom outlet of the light-removing tower is connected to a distillation tower through a pipeline, the top outlet of the distillation tower is connected to a stratified reflux tank through a second condenser, the gas phase outlet of the second condenser is connected to a second induced draft fan through a pipeline; the stratified reflux tank is connected to an MMA storage unit through a pipeline; the bottom outlet of the distillation tower is connected to an esterification unit through a pipeline; the tops of the light-removing tower and the distillation tower are respectively connected to inhibitor adding pipelines. The device, by utilizing the difference in boiling points of different components, realizes the effective separation of light components and heavy components in MMA through step-by-step distillation of the light-removing tower and the distillation tower, and significantly improves the purity of the product.

Description

Technical Field

[0001] The utility model belongs to the technical field of methyl methacrylate, and in particular relates to a methyl methacrylate refining device. Background Art

[0002] In the chemical industry, methyl methacrylate (MMA) is an important organic chemical raw material, widely used in coatings, adhesives, plastics and other fields. However, in the production process of MMA, due to the impurity of raw materials or the limitation of production process, the obtained crude MMA often contains impurities such as water, methanol, methacrylic acid, etc. The presence of these impurities will seriously affect the quality and application performance of MMA. Therefore, refining and purifying crude MMA to obtain high-purity MMA products has become an important technical problem.

[0003] The traditional MMA refining method mainly relies on distillation technology, which separates MMA from impurities by heating and collects MMA by condensation. However, since MMA is prone to polymerization at high temperatures, it is difficult to improve the purity and yield of MMA during the refining process. In addition, the traditional refining method also has problems such as high energy consumption and complex operation, which limits its application in industrial production. Utility Model Content

[0004] In view of the above deficiencies in the prior art, the purpose of the utility model is to provide a methyl methacrylate refining device, which, through the combined use of a light-removing tower and a distillation tower, not only achieves effective separation of light components and heavy components in MMA, thereby significantly improving product purity, but also effectively prevents the polymerization reaction of MMA during the refining process by adding an inhibitor, thereby further ensuring the purity of the product; at the same time, the device is also equipped with an incineration treatment unit to harmlessly treat the non-condensable gas generated during the refining process, thereby meeting environmental protection requirements.

[0005] The utility model is realized by adopting the following technical solutions:

[0006] The methyl methacrylate refining device comprises a light-removing tower, wherein the tower top outlet of the light-removing tower is connected to a first condenser through a pipeline, the liquid phase outlet of the first condenser is connected to a separation tank through a pipeline, and the gas phase outlet of the first condenser is connected to a first induced draft fan through a pipeline; the outlet of the separation tank is divided into two routes, one route is connected to the light-removing tower through a reflux pipeline, and the other route is connected to an esterification unit through a pipeline; the tower bottom outlet of the light-removing tower is connected to a distillation tower through a pipeline, the tower top outlet of the distillation tower is connected to a second condenser through a pipeline, the liquid phase outlet of the second condenser is connected to a stratified reflux tank through a pipeline, and the gas phase outlet of the second condenser is connected to a second induced draft fan through a pipeline; the outlet of the stratified reflux tank is divided into two routes, one route is connected to the distillation tower through a reflux pipeline, and the other route is connected to an MMA storage unit through a pipeline; the tower bottom outlet of the distillation tower is connected to the esterification unit through a pipeline; and the tops of the light-removing tower and the distillation tower are respectively connected to inhibitor adding pipelines.

[0007] The lightness removal tower and the distillation tower are also respectively connected with a tower bottom reboiler.

[0008] The inlet of the lightness removal tower is connected to the extraction unit through a pipeline.

[0009] The first induced draft fan and the second induced draft fan are connected to the incineration treatment unit through pipelines respectively.

[0010] The inlet of the polymerization inhibitor adding pipeline is respectively connected with the polymerization inhibitor pipeline and the solvent pipeline.

[0011] The inhibitor pipeline and the solvent pipeline are respectively provided with regulating valves; and the inlet pipelines from the inhibitor adding pipeline to the lightness removal tower and the distillation tower are respectively provided with switch valves.

[0012] The device described works as follows:

[0013] 1) Lightness removal tower (lightness removal operation):

[0014] The pre-treated crude MMA enters the light-removal tower from the extraction unit for primary distillation. In the light-removal tower, the light components (such as methanol, water, etc.) in the crude MMA are evaporated by heating due to the difference in boiling points of different components and discharged from the top of the tower. The steam discharged from the top of the tower enters the first condenser for condensation, and the condensate enters the separation tank for separation. The separation tank is divided into two phases of oil and water, of which the oil phase is refluxed to the light-removal tower through the reflux pipeline, and the water phase is sent to the esterification unit for further treatment.

[0015] 2) Distillation tower (refining operation):

[0016] The MMA solution flowing out from the bottom of the light-removal tower enters the distillation tower for deep refining. In the distillation tower, the difference in boiling points is continued to be used to separate MMA from heavy components (such as methacrylic acid, etc.). High-purity MMA vapor is discharged from the top of the distillation tower and enters the second condenser for condensation. The condensate enters the stratification reflux tank, where MMA is separated from trace amounts of water, methanol, etc. through stratification. The MMA phase part flows back to the distillation tower through the reflux pipeline and continues to participate in the distillation process to ensure the purity of the product. The other part is discharged to the MMA storage unit. The heavy components discharged from the bottom of the distillation tower are sent to the esterification unit for reprocessing.

[0017] 3) Addition of inhibitor:

[0018] At the top of the light-removal tower and the distillation tower, there are pipelines for adding polymerization inhibitors. The polymerization inhibitors and solvents are controlled by regulating valves and switch valves and added in a certain proportion to prevent polymerization of MMA during the refining process.

[0019] 4) Product collection:

[0020] The MMA purified by the distillation tower is transported to the MMA storage unit through a pipeline for storage.

[0021] 5) Waste gas treatment:

[0022] The gas phase outlets of the first condenser and the second condenser are connected to the first induced draft fan and the second induced draft fan respectively. The induced draft fan extracts the non-condensable gas (such as air, trace solvent vapor, etc.) and sends it to the incineration treatment unit for harmless treatment.

[0023] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0024] (1) The methyl methacrylate refining device of the utility model utilizes the difference in boiling points of different components and realizes the effective separation of light components and heavy components in MMA through step-by-step distillation of a light removal tower and a distillation tower, thereby significantly improving the purity of the product;

[0025] (2) The methyl methacrylate refining device described in the utility model is provided with an inhibitor adding pipeline at the top of the light removal tower and the distillation tower. By adding the inhibitor and the solvent, the polymerization reaction of MMA during the refining process is effectively prevented, and the purity and quality of the product are further guaranteed;

[0026] (3) The methyl methacrylate refining device described in the utility model is provided with a bottom reboiler in both the lightness removal tower and the distillation tower, which reduces the energy consumption in the refining process by recovering and utilizing the steam condensation heat; at the same time, the use of the induced draft fan also enables the effective utilization of the exhaust gas, further improving the energy utilization efficiency; in addition, the device is equipped with an incineration treatment unit to harmlessly treat the non-condensable gas generated in the refining process, which meets the environmental protection requirements and reduces the pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of the methyl methacrylate refining device described in the utility model;

[0028] In the figure: 1. light-removal tower; 2. first condenser; 3. separation tank; 4. first induced draft fan; 5. esterification unit; 6. distillation tower; 7. second condenser; 8. stratified reflux tank; 9. second induced draft fan; 10. MMA storage unit; 11. inhibitor addition pipeline; 12. bottom reboiler; 13. extraction unit; 14. incineration treatment unit; 15. inhibitor pipeline; 16. solvent pipeline; 17. regulating valve; 18. switch valve. DETAILED DESCRIPTION

[0029] In order to make the purpose and technical solution of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings.

[0030] Example 1

[0031] like Figure 1 As shown, the methyl methacrylate refining device comprises a light-removing tower 1, the top outlet of the light-removing tower 1 is connected to the first condenser 2 through a pipeline, the liquid phase outlet of the first condenser 2 is connected to the separation tank 3 through a pipeline, and the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the outlet of the separation tank 3 is divided into two routes, one of which is connected to the light-removing tower 1 through a reflux pipeline, and the other is connected to the esterification unit 5 through a pipeline; the bottom outlet of the light-removing tower 1 is connected to the distillation tower 6 through a pipeline, and the gas phase outlet of the distillation tower 6 ... gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase outlet of the first condenser 2 is connected to the first induced draft fan 4 through a pipeline; the gas phase The top outlet of the tower is connected to the second condenser 7 through a pipeline, the liquid phase outlet of the second condenser 7 is connected to the stratified reflux tank 8 through a pipeline, and the gas phase outlet of the second condenser 7 is connected to the second induced draft fan 9 through a pipeline; the outlet of the stratified reflux tank 8 is divided into two routes, one route is connected to the distillation tower 6 through a reflux pipeline, and the other route is connected to the MMA storage unit 10 through a pipeline; the bottom outlet of the distillation tower 6 is connected to the esterification unit 5 through a pipeline; the tops of the light removal tower 1 and the distillation tower 6 are respectively connected to the inhibitor addition pipeline 11.

[0032] The lightness removal tower 1 and the distillation tower 6 are also connected to a bottom reboiler 12 respectively.

[0033] The inlet of the light-removal tower 1 is connected to the extraction unit 13 through a pipeline.

[0034] The first induced draft fan 4 and the second induced draft fan 9 are connected to the incineration treatment unit 14 through pipelines respectively.

[0035] The inlet of the polymerization inhibitor adding pipeline 11 is connected to the polymerization inhibitor pipeline 15 and the solvent pipeline 16 respectively.

[0036] The inhibitor pipeline 15 and the solvent pipeline 16 are respectively provided with regulating valves 17; and the inlet pipelines from the inhibitor adding pipeline 11 to the lightness removal tower 1 and the distillation tower 6 are respectively provided with switch valves 18.

[0037] When working, the specific process is as follows:

[0038] 1. Raw material supply

[0039] The crude MMA is transported from the extraction unit 13 to the light removal column 1.

[0040] 2. Operation of Lightness Removal Tower 1

[0041] In the light removal tower 1, crude MMA is heated, and the light components (such as methanol, water, etc.) are gradually evaporated and discharged from the top of the tower by utilizing the difference in boiling points of its different components. These light components are condensed by the first condenser 2 and enter the separation tank 3 for oil-water separation. The separated oil phase is recycled to the light removal tower 1 to continue to participate in distillation, while the water phase flows into the esterification unit 5 for subsequent treatment.

[0042] 3. Distillation Tower 6 Deep Refining

[0043] The MMA solution flowing out from the bottom of the light removal tower 1 enters the distillation tower 6 for further refining. In the distillation tower 6, the heavy components (such as methacrylic acid, etc.) are effectively separated. High-purity MMA vapor escapes from the top of the tower, and after condensation in the second condenser 7, it enters the stratified reflux tank 8. In the tank, MMA and trace impurities such as water and methanol are separated by natural stratification. The pure MMA part is recovered to the distillation tower 6, and the other part is transported to the MMA storage unit 10 for storage.

[0044] 4. Addition of Inhibitor

[0045] In order to prevent polymerization of MMA during the refining process, an inhibitor adding pipeline 11 is provided at the top of the light removal tower 1 and the distillation tower 6. The inhibitor in the inhibitor pipeline 15 and the solvent in the solvent pipeline 16 are added into the tower in a preset ratio, precisely controlled by the regulating valve 17 and the switch valve 18, so as to maintain the stability of MMA.

[0046] 5. Waste gas treatment

[0047] During the refining process, the first condenser 2 and the second condenser 7 will produce non-condensable gas (such as air, trace solvent vapor, etc.). These waste gases are extracted through the first induced draft fan 4 and the second induced draft fan 9 and transported to the incineration treatment unit 14 for harmless treatment to meet environmental protection standards.

Claims

1. A methyl methacrylate refining device, characterized in that: The invention comprises a light-removal tower (1), wherein the tower top outlet of the light-removal tower (1) is connected to a first condenser (2) via a pipeline, the liquid phase outlet of the first condenser (2) is connected to a separation tank (3) via a pipeline, and the gas phase outlet of the first condenser (2) is connected to a first induced draft fan (4) via a pipeline; the outlet of the separation tank (3) is divided into two paths, one of which is connected to the light-removal tower (1) via a reflux pipeline, and the other is connected to an esterification unit (5) via a pipeline; the tower bottom outlet of the light-removal tower (1) is connected to a distillation tower (6) via a pipeline, and the tower top outlet of the distillation tower (6) is connected to a first induced draft fan (4) via a pipeline; The second condenser (7) is connected to the second condenser (7), the liquid phase outlet of the second condenser (7) is connected to the stratified reflux tank (8) through a pipeline, and the gas phase outlet of the second condenser (7) is connected to the second induced draft fan (9) through a pipeline; the outlet of the stratified reflux tank (8) is divided into two paths, one of which is connected to the distillation tower (6) through a reflux pipeline, and the other is connected to the MMA storage unit (10) through a pipeline; the bottom outlet of the distillation tower (6) is connected to the esterification unit (5) through a pipeline; the tops of the light removal tower (1) and the distillation tower (6) are respectively connected to the inhibitor addition pipeline (11).

2. The methyl methacrylate refining device according to claim 1, characterized in that: The light-removal tower (1) and the distillation tower (6) are also respectively connected to a tower bottom reboiler (12).

3. The methyl methacrylate refining device according to claim 2, characterized in that: The inlet of the lightness removal tower (1) is connected to the extraction unit (13) via a pipeline.

4. The methyl methacrylate refining device according to claim 3, characterized in that: The first induced draft fan (4) and the second induced draft fan (9) are respectively connected to the incineration treatment unit (14) through pipelines.

5. The methyl methacrylate refining device according to claim 4, characterized in that: The inlet of the polymerization inhibitor adding pipeline (11) is respectively connected to the polymerization inhibitor pipeline (15) and the solvent pipeline (16).

6. The methyl methacrylate refining device according to claim 5, characterized in that: The inhibitor pipeline (15) and the solvent pipeline (16) are respectively provided with regulating valves (17); and the inlet pipelines from the inhibitor adding pipeline (11) to the light removal tower (1) and the distillation tower (6) are respectively provided with switch valves (18).

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