A dimethyl sulfoxide rectification device
By designing a combination of distillation column, product column and reboiler, the problem of poor separation effect of crude dimethyl sulfoxide was solved, and high-purity, low-cost and stable production results were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHONGQING XINGFA JINGUAN CHEM IND CO LTD
- Filing Date
- 2025-06-12
- Publication Date
- 2026-05-29
AI Technical Summary
The existing crude dimethyl sulfoxide separation method is ineffective, resulting in unstable product quality, high maintenance costs, and high energy consumption, making it difficult to meet the requirements for high-purity separation.
Design a dimethyl sulfoxide distillation unit including a distillation column, a product column, and a reboiler. A combination of feed pipe, reflux pipe, constant discharge pipe, and steam jacket is used to achieve efficient separation and stable production.
It improves the purity and yield of dimethyl sulfoxide, reduces maintenance costs and energy consumption, and ensures product stability and continuity.
Smart Images
Figure CN224292552U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the chemical industry, and in particular to a dimethyl sulfoxide distillation apparatus. Background Technology
[0002] The crude dimethyl sulfoxide synthesized by chemical enterprises contains impurities such as water and salt, and needs to be separated to obtain a dimethyl sulfoxide product that meets the purity requirements.
[0003] Currently, chemical companies use distillation columns to perform negative pressure distillation of crude dimethyl sulfoxide (DMSO), collecting the vapor phase within a specific temperature range, and then condensing it to obtain the DMSO product. The following problems exist in this distillation process:
[0004] 1. It is not effective in separating crude dimethyl sulfoxide with complex composition and many impurities, and it is difficult to meet the requirements of high purity separation.
[0005] 2. During the distillation process, as time goes by and the composition of the materials in the column changes, it is difficult to keep the distillation conditions constant, resulting in large fluctuations in product quality and making it difficult to ensure product consistency and stability.
[0006] 3. The bottom product of the tower usually contains residue, which can easily cause blockage of pipelines or feed inlets. Regular cleaning and maintenance are required, which increases maintenance costs and downtime, and affects the continuity of production.
[0007] 4. The distillation column operates continuously, requiring a constant supply of heat and cold to maintain the distillation process, resulting in high overall energy consumption and increased production costs.
[0008] Therefore, designing a dimethyl sulfoxide distillation apparatus with high operating efficiency and high separation purity is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention
[0009] The purpose of this invention is to address the shortcomings of existing technologies by providing a dimethyl sulfoxide distillation apparatus that has a simple structure, low modification cost, can guarantee the purity of the separated dimethyl sulfoxide product, and improves the separation efficiency of the distillation apparatus.
[0010] The technical solution of this utility model is: a dimethyl sulfoxide distillation apparatus, comprising a distillation column, a product column, and a reboiler. A feed pipe is provided in the middle of the side wall of the distillation column and connected to a crude dimethyl sulfoxide source. A first gas phase pipe is provided at the top of the distillation column and connected to a negative pressure source. A second gas phase pipe is provided at the top of the product column and connected to a negative pressure source. A reflux pipe is provided at the top of the side wall of the product column and connected to the reflux port of the distillation column. The bottom of the side wall of the reboiler is connected to the bottom of the distillation column and the product column via a first pipe and a second pipe, respectively. The top of the side wall of the reboiler is connected to the middle of the side walls of the distillation column and the product column via a third pipe and a fourth pipe, respectively. The cross-sectional area of the fourth pipe is larger than that of the third pipe. A fixed-flow pipe is provided at the bottom of the reboiler.
[0011] Both the feed pipe and the fixed discharge pipe are equipped with steam jackets.
[0012] The downstream end of the reflux pipe is connected to a sprayer and is located in the distillation column.
[0013] The bottoms of the distillation column and the product column are at the same height, and the top of the product column is lower than the top of the distillation column. The distillation column is equipped with a first reflux pipe, and the product column is equipped with a second reflux pipe.
[0014] Both the first and second pipelines extend horizontally and are located at the same height.
[0015] The third and fourth pipes are of the same specifications, with one third pipe and two fourth pipes. Both the third and fourth pipes extend horizontally and are located at the same height.
[0016] The above technical solution has the following beneficial effects:
[0017] 1. A dimethyl sulfoxide (DMSO) distillation apparatus includes a distillation column, a product column, and a reboiler. A feed pipe is installed in the middle of the side wall of the distillation column, connected to a crude DMSO source. The crude DMSO enters the distillation column through the feed pipe. A first vapor phase pipe is installed at the top of the distillation column, connected to a negative pressure source. Impurity water vapor and a small amount of DMSO formed during flash evaporation in the distillation column are discharged through the first vapor phase pipe, completing water separation. A second vapor phase pipe is installed at the top of the product column, connected to a negative pressure source. Vaporous DMSO formed during flash evaporation in the product column is discharged through the second vapor phase pipe, yielding the finished product DMSO. A reflux pipe is installed at the top of the side wall of the product column, connected to the reflux port of the distillation column. A portion of the vaporous DMSO formed during flash evaporation in the product column flows through the reflux pipe, condenses, and is returned to the distillation column. This effectively reduces the amount of DMSO lost from the distillation column, increases the yield of DMSO, and reduces the difficulty of treating the discharged impurity water. The bottom of the reboiler's sidewall is connected to the bottom of the distillation column and the product column via a first pipe and a second pipe, respectively. Specifically, crude dimethyl sulfoxide (DMSO) entering the distillation column enters the reboiler via the first pipe, is heated to boiling, and forms a gaseous substance. The top of the reboiler's sidewall is connected to the middle of the distillation column and the product column via a third pipe and a fourth pipe, respectively. The fourth pipe has a larger cross-sectional area than the third pipe. The gaseous substance formed in the reboiler enters the distillation column via the third pipe and the product column via the fourth pipe, respectively. Furthermore, the gaseous flow rate entering the product column is larger than that entering the distillation column. Under stable production conditions, this increases the yield of DMSO and also increases the reflux flow rate of the distillation column, improving its temperature control capability. A drain pipe is installed at the bottom of the reboiler to periodically discharge residual heavy components, achieving continuous separation of DMSO.
[0018] 2. Both the feed pipe and the fixed discharge pipe are equipped with steam jackets. The steam jacket on the feed pipe is used to raise the feed temperature and improve the flash evaporation effect of impurity water in crude dimethyl sulfoxide in the distillation column. The steam jacket on the fixed discharge pipe is used to maintain the temperature. Heavy components remaining at the bottom of the reboiler are discharged through the fixed discharge pipe to prevent these heavy components from clogging due to crystallization during the discharge process. In addition, it also reduces the heat loss of the reboiler and ensures the evaporation efficiency of the material in the reboiler.
[0019] 3. The bottoms of the distillation column and the product column are at the same height, and the top of the product column is lower than the top of the distillation column. Under the same vacuum level, in the early stage of operation, by closing the second vapor phase tube and fully opening the reflux tube, more of the light components (mainly water) in the product column will enter the distillation column through the second vapor phase tube and be separated. More of the heavy components (dimethyl sulfoxide and trace amounts of dimethyl sulfone) in the product column will remain in the product column, thus improving the purity of the gaseous dimethyl sulfoxide in the product column. When the distillation unit is running stably, the purpose of continuously producing dimethyl sulfoxide product can be achieved by opening the second vapor phase tube and adjusting the opening of the reflux tube.
[0020] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details. Attached Figure Description
[0021] Figure 1 This is a connection diagram of the present invention.
[0022] In the attached diagram, 1 is a distillation column, 2 is a product column, 3 is a reboiler, 4 is a feed pipe, 5 is a first vapor phase pipe, 6 is a second vapor phase pipe, 7 is a reflux pipe, 8 is a fixed-flow pipe, 11 is a first pipeline, 12 is a second pipeline, 13 is a third pipeline, and 14 is a fourth pipeline. Detailed Implementation
[0023] See Figure 1This is a specific embodiment of a dimethyl sulfoxide (DMSO) distillation apparatus. The DMSO apparatus includes a distillation column 1, a product column 2, and a reboiler 3. Specifically, distillation column 1 and product column 2 are located at the same height, with the top of product column 2 lower than the top of distillation column 1. Both the distillation column and product column are equipped with corresponding top condensers and reflux pipes. The reboiler is located between the distillation column and product column. A feed pipe 4 is located in the middle of the side wall of distillation column 1, connected to a crude DMSO source. In this embodiment, the feed pipe 4 is equipped with a vapor jacket. A first vapor phase pipe 5 is located at the top of distillation column 1, connected to a negative pressure source. Obviously, the first vapor phase pipe passes through the condenser and is connected to the negative pressure source, which is common chemical engineering knowledge. A second vapor phase pipe 6 is located at the top of product column 2, connected to a negative pressure source. Similarly, the second vapor phase pipe passes through the condenser and is connected to the negative pressure source, which is common chemical engineering knowledge. A reflux pipe 7 is installed at the top of the side wall of the product column 2, connected to the reflux port of the distillation column 1. The gaseous dimethyl sulfoxide generated in the product column is refluxed back to the distillation column after being condensed into liquid through the reflux pipe. Furthermore, a sprayer is connected to the downstream end of the reflux pipe 7, located in the distillation column 1, and comes into countercurrent contact with the gaseous phase generated in the distillation column to reduce the content of dimethyl sulfoxide in the gaseous phase discharged from the distillation column. The bottom of the side wall of the reboiler 3 is connected to the bottom of the distillation column 1 and the product column 2 through a first pipe 11 and a second pipe 12, respectively. Specifically, the first pipe 11 and the second pipe 12 extend horizontally and are located at the same height. That is, the crude dimethyl sulfoxide entering the distillation column is sent to the reboiler to be heated to a boiling state, and the liquid phase material in the distillation column and the product column is heated. The top of the sidewall of reboiler 3 is connected to the middle of the sidewall of distillation column 1 and product column 2 via a third pipe 13 and a fourth pipe 14, respectively. The cross-sectional area of the fourth pipe is larger than that of the third pipe. Typically, the third pipe 13 and the fourth pipe 14 are designed to have the same specifications, with one third pipe 13 and two fourth pipes 14. Specifically, both the third pipe 13 and the fourth pipe 14 extend horizontally and are located at the same height, thus increasing the flow rate of the gaseous dimethyl sulfoxide generated in the reboiler into the product column. A fixed-flow pipe 8 is provided at the bottom of the reboiler 3, specifically, the fixed-flow pipe 8 is equipped with a steam jacket.
[0024] The working principle of this invention is as follows: In the early stage of operation, the second gas phase pipe is closed and the first gas phase pipe is opened. The crude dimethyl sulfoxide (containing impurities such as water and salt) is heated through the feed pipe and sent to the distillation column. The bottom liquid enters the reboiler and the product column through the first pipeline, maintaining a consistent liquid level. The reboiler heats the bottom liquid to boiling, generating a mixed gas phase of dimethyl sulfoxide, water, and dimethyl sulfoxide. The impurity salts remain in the bottom liquid. A small portion of the mixed gas phase enters the distillation column, while the majority of the mixed gas phase enters the product column. The water vapor in the mixed gas phase entering the product column remains in the gas phase and is discharged through the first gas phase pipe, carrying a small amount of dimethyl sulfoxide (DMSO) and trace amounts of DMSO. Most of the DMSO and DMSO are converted into liquid phase and enter the reboiler for re-vaporization. Most of the light component gas phase (water vapor) and a small amount of heavy component gas phase in the product column are returned to the distillation column through the reflux pipe. During the reflux process, the light component gas phase remains in the gas phase, while the heavy component gas phase partially liquefies, reducing the DMSO content in the exhaust gas phase from the distillation column. After the system stabilizes, the second gas phase pipe is opened, and the content of light component gas phase in the collected gas phase is significantly reduced, while the content of the target substance is significantly increased. The residual liquid in the reboiler is periodically discharged through the fixed drain pipe, realizing continuous distillation operation.
Claims
1. A dimethyl sulfoxide distillation apparatus, characterized in that: It includes a distillation column (1), a product column (2), and a reboiler (3). A feed pipe (4) is provided in the middle of the side wall of the distillation column (1), which is connected to a crude dimethyl sulfoxide source. A first gas phase pipe (5) is provided at the top of the distillation column (1), which is connected to a negative pressure source. The top of the product column (2) is provided with a second gas phase pipe (6) connected to a negative pressure source, and the top of the side wall of the product column (2) is provided with a reflux pipe (7) connected to the reflux port of the distillation column (1). The bottom of the sidewall of the reboiler (3) is connected to the bottom of the distillation column (1) and the product column (2) via the first pipe (11) and the second pipe (12), respectively. The top of the sidewall of the reboiler (3) is connected to the middle of the sidewall of the distillation column (1) and the product column (2) via the third pipe (13) and the fourth pipe (14), respectively. The cross-sectional area of the fourth pipe is larger than that of the third pipe. The bottom of the reboiler (3) is provided with a fixed-flow pipe (8).
2. The dimethyl sulfoxide distillation apparatus according to claim 1, characterized in that: Both the feed pipe (4) and the fixed discharge pipe (8) are equipped with steam jackets.
3. The dimethyl sulfoxide distillation apparatus according to claim 1, characterized in that: The downstream end of the reflux pipe (7) is connected to a sprayer and is located in the distillation column (1).
4. The dimethyl sulfoxide distillation apparatus according to claim 1, characterized in that: The bottoms of the distillation column (1) and the product column (2) are at the same height, and the top of the product column (2) is lower than the top of the distillation column (1). The distillation column (1) is equipped with a first reflux pipe, and the product column (2) is equipped with a second reflux pipe.
5. The dimethyl sulfoxide distillation apparatus according to claim 1, characterized in that: The first pipeline (11) and the second pipeline (12) both extend horizontally and are located at the same height.
6. The dimethyl sulfoxide distillation apparatus according to claim 1, characterized in that: The third pipe (13) and the fourth pipe (14) have the same specifications, and there is one third pipe (13) and two fourth pipes (14). The third pipe (13) and the fourth pipe (14) both extend horizontally and are located at the same height.