CN220360727U - Mixed gas separation system - Google Patents
Mixed gas separation system Download PDFInfo
- Publication number
- CN220360727U CN220360727U CN202321692815.1U CN202321692815U CN220360727U CN 220360727 U CN220360727 U CN 220360727U CN 202321692815 U CN202321692815 U CN 202321692815U CN 220360727 U CN220360727 U CN 220360727U
- Authority
- CN
- China
- Prior art keywords
- tower
- tail gas
- separation system
- rectifying tower
- buffer tank
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 238000000926 separation method Methods 0.000 title claims abstract description 31
- 238000003786 synthesis reaction Methods 0.000 claims abstract description 18
- 238000003860 storage Methods 0.000 claims abstract description 17
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 16
- 239000012071 phase Substances 0.000 claims abstract description 15
- 238000004891 communication Methods 0.000 claims abstract description 11
- 239000007791 liquid phase Substances 0.000 claims abstract description 10
- 238000012856 packing Methods 0.000 claims description 11
- 238000010521 absorption reaction Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 abstract description 26
- 239000000047 product Substances 0.000 abstract description 9
- 239000006227 byproduct Substances 0.000 abstract description 6
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 4
- 229910052717 sulfur Inorganic materials 0.000 abstract description 4
- 239000011593 sulfur Substances 0.000 abstract description 4
- XPVRBHCXMWRJEY-UHFFFAOYSA-N difluoro(imino)-$l^{4}-sulfane Chemical compound FS(F)=N XPVRBHCXMWRJEY-UHFFFAOYSA-N 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 90
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 12
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 12
- RAHZWNYVWXNFOC-UHFFFAOYSA-N sulfur dioxide Inorganic materials O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 9
- 239000000463 material Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 4
- 238000009835 boiling Methods 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 150000003949 imides Chemical class 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 235000010265 sodium sulphite Nutrition 0.000 description 2
- FYSNRJHAOHDILO-UHFFFAOYSA-N thionyl chloride Chemical compound ClS(Cl)=O FYSNRJHAOHDILO-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- -1 bis-fluorosulfonyl imide Chemical class 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011552 falling film Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- HRZFUMHJMZEROT-UHFFFAOYSA-L sodium disulfite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])(=O)=O HRZFUMHJMZEROT-UHFFFAOYSA-L 0.000 description 1
- 229940001584 sodium metabisulfite Drugs 0.000 description 1
- 235000010262 sodium metabisulphite Nutrition 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Landscapes
- Separation By Low-Temperature Treatments (AREA)
Abstract
The utility model belongs to a gasThe technical field of separation, and discloses a mixed gas separation system. The device comprises a synthesis tail gas buffer tank, a high-pressure tail gas buffer tank, a first condensing device, a liquefied tail gas buffer tank, a first rectifying tower and a second rectifying tower; the synthetic tail gas buffer tank is communicated with the high-pressure tail gas buffer tank through a tail gas compressor; the upper end of the first rectifying tower is connected with a first tower top condenser, and the lower end of the first rectifying tower is connected with a first tower bottom reboiler; the upper end of the second rectifying tower is connected with a second tower top condenser, and the lower end of the second rectifying tower is connected with a second tower bottom reboiler; the mixed gas separation system further comprises a gas absorbing device in communication with the gas phase outlet of the first condensing device and the gas phase outlet of the first overhead condenser, and a first storage tank in communication with the liquid phase outlet of the second overhead condenser. The utility model has simple structure, is suitable for treating tail gas generated in the production of the difluoro sulfimide, can reduce the sulfur content in the byproduct hydrochloric acid, and ensures the product quality; improving by-product SO 2 The purity of the product is improved.
Description
Technical Field
The utility model belongs to the technical field of gas separation, relates to a mixed gas separation system, and in particular relates to a tail gas separation system for bis-fluorosulfonyl imide production.
Background
In the industrial production of bisfluorosulfonyl imide, various mixed gases (SO) are produced in the first reaction step 2 、HCl、SOCl 2 ) Is difficult to separate. At present, multistage falling film absorption is generally adopted to lead SOCl therein 2 React with water to generate SO 2 HCl, by SO 2 Unlike HCl, HCl is dissolved in water to form hydrochloric acid with concentration of 30%, and the rest is SO with a small amount of water vapor 2 The sodium sulfite device is absorbed by sodium carbonate, so that the sulfur content in the hydrochloric acid is too high when the sodium sulfite device is used for treatment, the treatment of the hydrochloric acid is difficult, and the chloride ion content of a sodium metabisulfite product is too high to corrode equipment.
Disclosure of Invention
The utility model aims to provide a mixed gas separation system, which is used for treating tail gas from the production of bisfluorosulfonyl imide, reducing the sulfur content in byproduct hydrochloric acid and improving byproduct SO 2 Is a pure product of (a).
In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows:
a mixed gas separation system comprises a synthesis tail gas buffer tank, a high-pressure tail gas buffer tank, a first condensing device, a liquefied tail gas buffer tank, a first rectifying tower and a second rectifying tower which are communicated in sequence; the synthetic tail gas buffer tank is provided with a synthetic tail gas inlet, and is communicated with the high-pressure tail gas buffer tank through a tail gas compressor;
the upper end of the first rectifying tower is connected with a first tower top condenser, and the lower end of the first rectifying tower is connected with a first tower bottom reboiler;
the upper end of the second rectifying tower is connected with a second tower top condenser, and the lower end of the second rectifying tower is connected with a second tower bottom reboiler;
the mixed gas separation system further comprises a gas absorption device communicated with the gas phase outlet of the first condensing device and the gas phase outlet of the first tower top condenser, and a first storage tank communicated with the liquid phase outlet of the second tower top condenser.
Further, a first return pipe is arranged between the synthesis tail gas buffer tank and the high-pressure tail gas buffer tank.
Further, a booster pump is arranged between the liquefied tail gas buffer tank and the first rectifying tower.
Further preferably, a second return pipe is arranged between the feed inlet of the first rectifying tower and the liquefied tail gas buffer tank.
Further, the first condensing device comprises a first-stage condenser and a second-stage condenser, a liquid phase outlet of the first-stage condenser and a liquid phase outlet of the second-stage condenser are communicated with the liquefied tail gas buffer tank, a gas phase outlet of the first-stage condenser is communicated with an input end of the second-stage condenser, and a gas phase outlet of the second-stage condenser is communicated with the gas absorption device.
Further, the gas absorbing device is a water absorbing device.
Further, the mixed gas separation system also comprises a tail gas absorption device communicated with the gas phase outlet of the second tower top condenser.
Further, the mixed gas separation system also comprises a second storage tank communicated with a bottom discharge port of the second rectifying tower; or the bottom discharge port of the second rectifying tower is directly communicated with the synthesis kettle.
Further, the first rectifying tower is a corrugated plate packing tower, and is provided with 4 sections of corrugated plate packing, including 2 sections of rectifying sections and 2 sections of stripping sections; the second rectifying tower is a corrugated plate packing tower, and is provided with 4 sections of corrugated plate packing, including 2 sections of rectifying sections and 2 sections of stripping sections.
Further, valves are arranged on communication pipelines of all components of the mixed gas separation system.
Compared with the prior art, the utility model has the beneficial effects that:
the mixed gas separation system has simple structure and is suitable for the tail gas (SO) produced by the difluoro sulfimide 2 、HCl、SOCl 2 ) In the operation process, the system can increase the boiling point of each material by pressurizing, so that the boiling point difference between the three materials is increased, and the purity of the separated materials is improved. The method comprises the following steps: the sulfur content in the byproduct hydrochloric acid is reduced, and the product quality is ensured; increase of by-product SO 2 The purity of the product is improved.
Drawings
The accompanying drawings are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate the utility model and together with the embodiments of the utility model, serve to explain the utility model. In the drawings:
FIG. 1 is a schematic diagram of a mixed gas separation system according to the present utility model;
wherein: 1-synthesis tail gas buffer tank, 101-synthesis tail gas inlet, 2-tail gas compressor, 3-high pressure tail gas buffer tank, 4-liquefied tail gas buffer tank, 5-first-stage condenser, 6-second-stage condenser, 7-first rectifying tower, 8-first tower bottom reboiler, 9-first tower top condenser, 10-second rectifying tower, 11-second tower bottom reboiler, 12-second tower top condenser, 13-second storage tank, 14-first storage tank, 15-sulfur dioxide finished product, 16-tail gas absorbing device, 17-gas absorbing device, 18-first return pipe and 19-second return pipe.
Detailed Description
The present utility model will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments are shown, for the purpose of illustrating the utility model, but the scope of the utility model is not limited to the specific embodiments shown.
Unless defined otherwise, all technical and scientific terms used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the scope of the present utility model.
Unless otherwise specifically indicated, the various raw materials, reagents, instruments, equipment and the like used in the present utility model are commercially available or may be prepared by existing methods.
Examples
Referring to fig. 1, the present embodiment discloses a mixed gas separation system including a synthesis gas buffer tank 1, a high-pressure tail gas buffer tank 3, a first condensing device, a liquefied tail gas buffer tank 4, a first rectifying tower 7, a second rectifying tower 10, a first storage tank 14, a second storage tank 13, a tail gas compressor 2, a tail gas absorbing device 16, and a gas absorbing device 17.
In the embodiment, a synthesis tail gas buffer tank 1, a high-pressure tail gas buffer tank 3, a first condensing device, a liquefied tail gas buffer tank 4, a first rectifying tower 7 and a second rectifying tower 10 are sequentially communicated; the synthesis tail gas buffer tank 1 is provided with a synthesis tail gas inlet 101, and the synthesis tail gas buffer tank 1 is communicated with the high-pressure tail gas buffer tank 3 through a tail gas compressor 2; valves are arranged on communication pipelines of all components of the mixed gas separation system.
In this embodiment, the upper end of the first rectifying tower 7 is connected to a first tower top condenser 9, and the lower end is connected to a first tower bottom reboiler 8; the upper end of the second rectifying tower 10 is connected with a second tower top condenser 12, the lower end of the second rectifying tower is connected with a second tower bottom reboiler 11, a first storage tank 14 is communicated with a liquid phase outlet of the second tower top condenser 12, a tail gas absorbing device 16 is communicated with a gas phase outlet of the second tower top condenser 12, and a second storage tank 13 is communicated with a bottom discharge hole of the second rectifying tower 10.
In this embodiment, the first condensation device includes a first-stage condenser 5 and a second-stage condenser 6, where a liquid-phase outlet of the first-stage condenser 5 and a liquid-phase outlet of the second-stage condenser 6 are communicated with the liquefied tail gas buffer tank 4, a gas-phase outlet of the first-stage condenser 5 is communicated with an input end of the second-stage condenser 6, and a gas-phase outlet of the second-stage condenser 6 is communicated with the gas absorption device 17.
In this embodiment, a first return pipe 18 is disposed between the synthesis tail gas buffer tank 1 and the high-pressure tail gas buffer tank 3, and a regulating valve is disposed on the first return pipe 18, so that due to the fluctuation of the synthesis tail gas pressure, the intake pressure of the tail gas compressor 2 can be stabilized through the arrangement of the first return pipe 18 and the regulating valve, and the stable operation of the system is maintained.
In this embodiment, a booster pump is disposed between the liquefied tail gas buffer tank 4 and the first rectifying tower 7. A second return pipe 19 is arranged between the feed inlet of the first rectifying tower 7 and the liquefied tail gas buffer tank 4, so that the minimum flow of the outlet of the booster pump is ensured, the stable operation of the booster pump is ensured,
as one of preferable aspects of the present embodiment, the gas absorbing device 17 is a hydrogen chloride gas absorbing device, specifically a water absorbing device.
As one of the preferable schemes of the embodiment, the first storage tank 14 is a sulfur dioxide storage tank, and the output of the first storage tank 14 is a sulfur dioxide finished product 15.
As one of preferable aspects of the present embodiment, the second tank 13 is a thionyl chloride tank, and the second tank 13 may be in communication with a synthesis tank of the preceding process.
As one of the preferable aspects of the present embodiment, the tail gas absorbing device 16 is an alkali liquor spraying absorbing device. Preventing the second overhead condenser 12 from controlling too high in temperature, resulting in a portion of SO 2 Overflow leakage and absorption of hydrogen chloride gas leaking from the first rectifying tower 7 into the second rectifying tower 10 are also possible.
As one of the preferable schemes of the embodiment, the first rectifying tower 7 is a corrugated plate packing tower, 4 sections of corrugated plate packing are arranged on the first rectifying tower 7, and each section comprises 2 rectifying sections and 2 stripping sections, and the height of each section is 3.2m; the second rectifying tower 10 is a corrugated plate packing tower, and the second rectifying tower 10 is provided with 4 sections of corrugated plate packing, including 2 rectifying sections and 2 stripping sections, and the height of each section is 3.2m.
As one of the preferable aspects of the present embodiment, the synthesis off-gas buffer tank 1, the off-gas compressor 2, the high-pressure off-gas buffer tank 3, the liquefied off-gas buffer tank 4, the primary condenser 5, the secondary condenser 6, the first tower bottom reboiler 8, the first tower top condenser 9, the second tower bottom reboiler 11, the second tower top condenser 12, and the second storage tank 13 are provided with a heating medium jacket or a cooling medium jacket, providing a circulating medium inlet and a circulating medium outlet.
As one of preferable aspects of the present embodiment, the operation principle of the mixed gas separation system of the present embodiment is as follows:
the device uses the synthetic tail gas buffer tank to produce tail gas (the main component is SO) for the difluoro sulfimide 2 、HCl、SOCl 2 ) Collecting, pressurizing to 1.6Mpa by a tail gas compressor, storing in a high-pressure tail gas buffer tank, condensing and liquefying by a first condensing device, and collecting in a liquefied tail gas buffer tank;
pumping the liquefied tail gas buffer tank into a first rectifying tower through a booster pump to separate hydrogen chloride gas in the mixed gas, pressurizing the first rectifying tower to 2.1MPa, enabling the hydrogen chloride gas to be in a semi-condensation state, discharging the pure hydrogen chloride gas which is discharged from the top of the first rectifying tower, and discharging the pure hydrogen chloride gas to a water absorption device to be made into 30% hydrochloric acid solution for recycling;
the heavy component materials in the first rectifying tower enter the second rectifying tower through pressure difference to separate sulfur dioxide gas from the liquefied materials, the second rectifying tower is controlled to be pressurized to 0.6mpa and SO is controlled to be pressurized 2 Boiling point is about 40 ℃, and the top temperature of the tower is controlled at 40 ℃ to SO 2 Purifying, wherein sulfur dioxide is in a semi-condensation state at the top of the tower, and SO is in the top of the tower 2 After condensing and liquefying, collecting the liquid in a first storage tank, and obtaining SO 2 Selling the finished product;
SOCl remained in the bottom of the second rectifying tower 2 Can be collected to a second storage tank or transmitted to the front-end synthesis process for recycling.
The above is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the scope of the present utility model.
Claims (10)
1. The mixed gas separation system is characterized by comprising a synthesis tail gas buffer tank, a high-pressure tail gas buffer tank, a first condensing device, a liquefied tail gas buffer tank, a first rectifying tower and a second rectifying tower which are sequentially communicated; the synthetic tail gas buffer tank is provided with a synthetic tail gas inlet, and is communicated with the high-pressure tail gas buffer tank through a tail gas compressor;
the upper end of the first rectifying tower is connected with a first tower top condenser, and the lower end of the first rectifying tower is connected with a first tower bottom reboiler;
the upper end of the second rectifying tower is connected with a second tower top condenser, and the lower end of the second rectifying tower is connected with a second tower bottom reboiler;
the mixed gas separation system further comprises a gas absorption device communicated with the gas phase outlet of the first condensing device and the gas phase outlet of the first tower top condenser, and a first storage tank communicated with the liquid phase outlet of the second tower top condenser.
2. The mixed gas separation system of claim 1, wherein a first return line is disposed between the synthesis off-gas surge tank and the high pressure off-gas surge tank.
3. The mixed gas separation system according to claim 1, wherein a booster pump is provided between the liquefied tail gas buffer tank and the first rectifying tower.
4. The mixed gas separation system as claimed in claim 2, wherein a second return line is provided between the feed inlet of the first rectifying column and the liquefied tail gas buffer tank.
5. The mixed gas separation system of claim 1, wherein the first condensing means comprises a primary condenser and a secondary condenser, the liquid phase outlet of the primary condenser and the liquid phase outlet of the secondary condenser are in communication with a liquefied tail gas buffer tank, the gas phase outlet of the primary condenser is in communication with the input of the secondary condenser, and the gas phase outlet of the secondary condenser is in communication with the gas absorbing means.
6. The mixed gas separation system of claim 1, wherein the gas absorbing device is a water absorbing device.
7. The mixed gas separation system of claim 1, further comprising an off-gas absorbing device in communication with the gas phase outlet of the second overhead condenser.
8. The mixed gas separation system of claim 1, further comprising a second storage tank in communication with a bottom discharge of the second rectification column.
9. The mixed gas separation system according to claim 1, wherein the first rectifying tower is a corrugated plate packed tower, and 4 sections of corrugated plate packing are arranged in the first rectifying tower, and the first rectifying tower comprises 2 rectifying sections and 2 stripping sections; the second rectifying tower is a corrugated plate packing tower, and is provided with 4 sections of corrugated plate packing, including 2 sections of rectifying sections and 2 sections of stripping sections.
10. The mixed gas separation system according to any one of claims 1 to 9, wherein valves are provided on communication pipes of the respective components of the mixed gas separation system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321692815.1U CN220360727U (en) | 2023-06-30 | 2023-06-30 | Mixed gas separation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321692815.1U CN220360727U (en) | 2023-06-30 | 2023-06-30 | Mixed gas separation system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220360727U true CN220360727U (en) | 2024-01-19 |
Family
ID=89519908
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321692815.1U Active CN220360727U (en) | 2023-06-30 | 2023-06-30 | Mixed gas separation system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220360727U (en) |
-
2023
- 2023-06-30 CN CN202321692815.1U patent/CN220360727U/en active Active
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