CN113800484A - Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas - Google Patents
Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas Download PDFInfo
- Publication number
- CN113800484A CN113800484A CN202111119064.XA CN202111119064A CN113800484A CN 113800484 A CN113800484 A CN 113800484A CN 202111119064 A CN202111119064 A CN 202111119064A CN 113800484 A CN113800484 A CN 113800484A
- Authority
- CN
- China
- Prior art keywords
- recovery tower
- tail gas
- nitrogen trifluoride
- gas
- vented
- 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.)
- Pending
Links
- 238000011084 recovery Methods 0.000 title claims abstract description 92
- 239000007789 gas Substances 0.000 title claims abstract description 81
- QKCGXXHCELUCKW-UHFFFAOYSA-N n-[4-[4-(dinaphthalen-2-ylamino)phenyl]phenyl]-n-naphthalen-2-ylnaphthalen-2-amine Chemical compound C1=CC=CC2=CC(N(C=3C=CC(=CC=3)C=3C=CC(=CC=3)N(C=3C=C4C=CC=CC4=CC=3)C=3C=C4C=CC=CC4=CC=3)C3=CC4=CC=CC=C4C=C3)=CC=C21 QKCGXXHCELUCKW-UHFFFAOYSA-N 0.000 title claims abstract description 52
- 238000000034 method Methods 0.000 title claims abstract description 17
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 36
- 238000000746 purification Methods 0.000 claims abstract description 18
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 17
- 239000007788 liquid Substances 0.000 claims abstract description 16
- 238000000465 moulding Methods 0.000 claims description 15
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 6
- 238000003825 pressing Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 230000008569 process Effects 0.000 claims description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 3
- 239000001569 carbon dioxide Substances 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- 239000003513 alkali Substances 0.000 claims 1
- 238000005336 cracking Methods 0.000 claims 1
- 239000001257 hydrogen Substances 0.000 claims 1
- 229910052739 hydrogen Inorganic materials 0.000 claims 1
- 239000012535 impurity Substances 0.000 claims 1
- 238000006722 reduction reaction Methods 0.000 claims 1
- 238000005530 etching Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 239000012459 cleaning agent Substances 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- -1 fluorine ions Chemical class 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 238000000992 sputter etching Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 150000003658 tungsten compounds Chemical class 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/082—Compounds containing nitrogen and non-metals and optionally metals
- C01B21/083—Compounds containing nitrogen and non-metals and optionally metals containing one or more halogen atoms
- C01B21/0832—Binary compounds of nitrogen with halogens
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Separation By Low-Temperature Treatments (AREA)
Abstract
The invention provides equipment for recovering nitrogen trifluoride gas from vented tail gas, which comprises a primary recovery tower and a secondary recovery tower, wherein the upper end of the primary recovery tower is connected with a first connecting pipe, the upper end of the secondary recovery tower is connected with a second connecting pipe, one end of the primary recovery tower is connected with a first mould press, one end of the secondary recovery tower is connected with a second mould press, and one end of the second mould press is connected with a purification conveying pipeline; the invention also discloses a method for recovering nitrogen trifluoride gas from the vented tail gas, which comprises the following steps. According to the invention, the vented tail gas is pressurized to the recovery tower by using the mould press, the temperature of the recovery tower is controlled by using liquid nitrogen, so that the recovery of nitrogen trifluoride in the tail gas is realized, and the standard emission of nitrogen trifluoride in the emitted tail gas is realized.
Description
Technical Field
The invention belongs to the technical field of nitrogen trifluoride recovery, and particularly relates to a recovery device and a recovery method for nitrogen trifluoride gas in exhausted tail gas.
Background
Nitrogen trifluoride is a colorless, odorless and stable gas at normal temperature, is a strong oxidant, is used as an excellent plasma etching gas in the microelectronic industry, is cracked into active fluorine ions during ion etching, has excellent etching rate and selectivity (for silicon oxide and silicon) for silicon and tungsten compounds, is a very good cleaning agent for high-purity nitrogen trifluoride, does not leave any residue on the surface of an etching object during etching, and is widely applied to chip manufacturing and high-energy lasers.
Nitrogen trifluoride has excellent etching rate and selectivity, no residue is left on the surface of an etched object, and the nitrogen trifluoride is also a very good cleaning agent. With the development of nanotechnology and the large-scale development of technology in the electronics industry, the demand for it will increase.
However, the collection rate is low in the existing preparation process of nitrogen trifluoride, the emission of the content of nitrogen trifluoride in the emptying tail gas is not up to the standard, and the air is polluted; therefore, an apparatus and a method for recovering nitrogen trifluoride gas from vented tail gas are provided to solve the above problems.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a device for recovering nitrogen trifluoride gas from vented tail gas, aiming at overcoming the defects of the prior art, and solving the problems proposed in the background art.
In order to solve the technical problems, the invention adopts the technical scheme that:
in a first aspect, the equipment for recovering nitrogen trifluoride gas from the exhausted tail gas comprises a primary recovery tower and a secondary recovery tower, wherein one end of the secondary recovery tower is connected with a second mould press, one end of the second mould press is connected with a purification conveying pipeline, the upper end of the primary recovery tower is connected with a first connecting pipe, one end of the first connecting pipe is connected to one side of the purification conveying pipeline, the upper end of the secondary recovery tower is connected with a second connecting pipe, one end of the purification conveying pipeline is connected to the upper end of the second connecting pipe, one end of the second connecting pipe is connected with a fixed pipe, and a delivery pipe is connected to the purification conveying pipeline;
the other side end of the primary recovery tower is also connected with a first molding press.
Furthermore, one side of the upper end of the first-stage recovery tower and one side of the upper end of the second-stage recovery tower are respectively connected with a cold nitrogen discharge pipe, and one side of the lower end of the first-stage recovery tower and one side of the lower end of the second-stage recovery tower are respectively connected with a liquid nitrogen conveying pipe.
Furthermore, the lower ends of the first molding press and the second molding press are respectively fixed with a mounting bracket.
Further, the lower end of the first molding press is connected with a tail gas emptying pipe.
Furthermore, the upper ends of the first connecting pipe and the second connecting pipe are respectively provided with a pressure reducing valve.
In a second aspect, the method for recovering nitrogen trifluoride gas from the vented tail gas comprises the following steps:
s1, pressurizing the vented tail gas in the pretreatment stage by a first mould pressing machine, and enabling the vented tail gas to enter a primary recovery tower;
s2, controlling recovery by using liquid nitrogen in a primary recovery tower, and liquefying most of nitrogen trifluoride in the vented tail gas;
s3, re-pressurizing the residual tail gas treated by the primary recovery tower through a second mould press, and enabling the residual tail gas to enter a secondary recovery tower, wherein the pressure and the temperature are the same as the parameters of the primary recovery tower, so that the further recovery of the residual nitrogen trifluoride is realized;
and S4, performing secondary recovery by a secondary recovery tower, wherein the content of nitrogen trifluoride in tail gas reaches below 3ppm, heating the secondary recovery tower when the liquid level of the recovery tower reaches 1/3, and further purifying the gasified nitrogen trifluoride in a purification section through a discharge pipe.
Further, in S1, the pressure of the first molding press is 5 to 7 MPa.
Further, in S1, the vent tail gas is the vent tail gas of the pretreatment stage in the production, and the vent tail gas mainly comprises 98-98.5% of nitrogen, 1% of nitrogen trifluoride and the balance of carbon dioxide.
Further, in S2, the liquid nitrogen is controlled to recover at a temperature of-45 ℃ to-95 ℃.
Compared with the prior art, the invention has the following advantages:
according to the recovery process, the vented tail gas is pressurized to the recovery tower through the mould press, the temperature of the recovery tower is controlled by using liquid nitrogen, so that the recovery of nitrogen trifluoride in the vented tail gas is realized, and the emission requirement of the content of nitrogen trifluoride in the exhausted tail gas is met.
Drawings
FIG. 1 is a flow chart of the apparatus of the present invention.
The system comprises a guide pipe 1, a purification conveying pipeline 2, a pressure reducing valve 3, a cold nitrogen gas discharge pipe 4, a primary recovery tower 5, a first mould press 6, a tail gas vent pipe 7, an installation support 8, a second mould press 9, a second connecting pipe 10, a fixed pipe 11, a secondary recovery tower 12, a liquid nitrogen conveying pipe 13 and a first connecting pipe 14.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In this embodiment, the upper end side of the first-stage recovery tower 5 and the upper end side of the second-stage recovery tower 12 are both connected with a cold nitrogen gas discharge pipe 4, and the lower end side of the first-stage recovery tower 5 and the lower end side of the second-stage recovery tower 12 are both connected with a liquid nitrogen delivery pipe 13.
In this embodiment, the lower ends of the first molding press 6 and the second molding press 9 are both fixed with a mounting bracket 8, the lower end of the first molding press 6 is connected with a tail gas vent pipe 7, and the upper ends of the first connecting pipe 14 and the second connecting pipe 10 are both provided with a pressure reducing valve 3, which facilitates internal pressure adjustment.
s1, pressurizing the vent tail gas in the pretreatment stage by a first mould press 6, wherein the vent tail gas is the vent tail gas in the pretreatment stage in the production process and mainly comprises 98-98.5% of nitrogen, 1% of nitrogen trifluoride and the balance of carbon dioxide, and the pressure of the first mould press 6 is 5-7MPa, so that the vent tail gas enters a primary recovery tower 5;
s2, controlling recovery by using liquid nitrogen in a primary recovery tower 5, and liquefying most of nitrogen trifluoride in the vented tail gas;
s3, re-pressurizing the residual tail gas treated by the primary recovery tower 5 by a second mould press 9, enabling the residual tail gas to enter a secondary recovery tower 12, wherein the pressure and the temperature are the same as the parameters of the primary recovery tower 5, further recovering the residual nitrogen trifluoride, and controlling the recovery temperature to be-45 ℃ to-95 ℃ by liquid nitrogen;
s4, performing secondary recovery by the secondary recovery tower 12, wherein the content of nitrogen trifluoride in tail gas reaches below 3ppm, when the liquid level of the recovery tower reaches 1/3, heating the secondary recovery tower 12, and further purifying the gasified nitrogen trifluoride by a purification section through a discharge pipe 1.
The method has the main advantages that the low-concentration nitrogen trifluoride gas is pressurized by the mould press, the boiling point of the nitrogen trifluoride gas at high pressure is reduced, the nitrogen trifluoride gas is easy to liquefy and recycle, and the low-concentration nitrogen trifluoride gas is fully recycled by the secondary recycling device.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (9)
1. The utility model provides a nitrogen trifluoride gas recovery plant in unloading tail gas which characterized in that: the device comprises a primary recovery tower (5) and a secondary recovery tower (12), wherein one end of the secondary recovery tower (12) is connected with a second mould pressing machine (9), one end of the second mould pressing machine (9) is connected with a purification conveying pipeline (2), the upper end of the primary recovery tower (5) is connected with a first connecting pipe (14), one end of the first connecting pipe (14) is connected to one side of the purification conveying pipeline (2), the upper end of the secondary recovery tower (12) is connected with a second connecting pipe (10), one end of the purification conveying pipeline (2) is connected to the upper end of the second connecting pipe (10), one end of the second connecting pipe (10) is connected with a fixed pipe (11), and the purification conveying pipeline (2) is connected with a guide pipe (1);
the other side end of the primary recovery tower (5) is also connected with a first mould press (6).
2. The equipment for recovering nitrogen trifluoride gas from vented tail gas according to claim 1, wherein the primary recovery tower (5) and the secondary recovery tower (12) are connected at their upper ends with a cold nitrogen discharge pipe (4) respectively, and the primary recovery tower (5) and the secondary recovery tower (12) are connected at their lower ends with a liquid nitrogen delivery pipe (13) respectively.
3. The apparatus for recovering nitrogen trifluoride gas from vented tail gas as claimed in claim 1, wherein mounting brackets (8) are fixed to the lower ends of said first molding press (6) and said second molding press (9), respectively.
4. A plant for the recovery of nitrogen trifluoride gas from vented offgas according to claim 1, characterized in that the lower end of the first molding press (6) is connected to an offgas vent pipe (7).
5. The apparatus for recovering nitrogen trifluoride gas from vented tail gas according to claim 1, wherein the first connecting pipe (14) and the second connecting pipe (10) are each provided with a pressure reducing valve (3).
6. A method for recovering nitrogen trifluoride gas from vented tail gas is characterized by comprising the following steps:
s1, pressurizing the vented tail gas in the pretreatment stage by a first mould pressing machine (6) to enable the vented tail gas to enter a primary recovery tower (5);
s2, controlling recovery by using liquid nitrogen in a primary recovery tower (5), and liquefying most of nitrogen trifluoride in the vented tail gas;
s3, re-pressurizing the residual tail gas treated by the primary recovery tower (5) through a second mould pressing machine (9) to enable the residual tail gas to enter a secondary recovery tower (12), wherein the pressure and the temperature are the same as the parameters of the primary recovery tower (5), and further recovering the residual nitrogen trifluoride;
s4, performing secondary recovery by a secondary recovery tower (12), wherein the content of nitrogen trifluoride in tail gas discharged from a fixed pipe (11) is less than 3 ppm; when the liquid level of the first-stage recovery tower (5) reaches 1/2 or the liquid level of the second-stage recovery tower (12) reaches 1/3, the first-stage recovery tower (5) and the second-stage recovery tower (12) are heated by standby recovery equipment for recovery, and gasified nitrogen trifluoride is sent to a subsequent purification section through a discharge pipe (1): the high-purity nitrogen trifluoride gas with the purity of more than 99.995 percent is obtained through the working procedures of cracking, washing, reduction, alkali washing, continuous rectification and the like.
7. A process for recovering nitrogen trifluoride gas from vented offgas according to claim 6, wherein in S1, the pressure of the first molding press (6) is 5 to 7 MPa.
8. The method for recovering nitrogen trifluoride gas from vent tail gas according to claim 6, wherein in S1, the vent tail gas is vent tail gas from pretreatment stage in production, and its composition includes the following gases by volume percent: 98-98.5% of nitrogen, 1-1.5% of nitrogen trifluoride and the balance of carbon dioxide, hydrogen and impurities thereof.
9. The method for recovering nitrogen trifluoride gas from vented tail gas according to claim 6, wherein the temperature of the liquid nitrogen controlled recovery at S2 is controlled to be from-45 ℃ to-95 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111119064.XA CN113800484A (en) | 2021-09-24 | 2021-09-24 | Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111119064.XA CN113800484A (en) | 2021-09-24 | 2021-09-24 | Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113800484A true CN113800484A (en) | 2021-12-17 |
Family
ID=78896497
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111119064.XA Pending CN113800484A (en) | 2021-09-24 | 2021-09-24 | Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113800484A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0771887A1 (en) * | 1995-11-06 | 1997-05-07 | Teisan Kabushiki Kaisha | Gas recovery unit |
| CN1287018A (en) * | 1999-06-28 | 2001-03-14 | 普拉塞尔技术有限公司 | Method and system for recovering perfluor compound by condensation |
| US6276168B1 (en) * | 2000-05-08 | 2001-08-21 | Air Products And Chemicals, Inc. | Purification of nitrogen trifluoride by continuous cryogenic distillation |
| KR101163959B1 (en) * | 2011-12-02 | 2012-07-06 | 오씨아이머티리얼즈 주식회사 | Apparatus and method for liquefing nitrogen trifluoride gas |
| CN112624049A (en) * | 2020-11-29 | 2021-04-09 | 云南能投化工有限责任公司 | Comprehensive hydrogen chloride gas recovery device and method |
-
2021
- 2021-09-24 CN CN202111119064.XA patent/CN113800484A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0771887A1 (en) * | 1995-11-06 | 1997-05-07 | Teisan Kabushiki Kaisha | Gas recovery unit |
| CN1287018A (en) * | 1999-06-28 | 2001-03-14 | 普拉塞尔技术有限公司 | Method and system for recovering perfluor compound by condensation |
| US6276168B1 (en) * | 2000-05-08 | 2001-08-21 | Air Products And Chemicals, Inc. | Purification of nitrogen trifluoride by continuous cryogenic distillation |
| KR101163959B1 (en) * | 2011-12-02 | 2012-07-06 | 오씨아이머티리얼즈 주식회사 | Apparatus and method for liquefing nitrogen trifluoride gas |
| CN112624049A (en) * | 2020-11-29 | 2021-04-09 | 云南能投化工有限责任公司 | Comprehensive hydrogen chloride gas recovery device and method |
Non-Patent Citations (1)
| Title |
|---|
| 施苗: "《动手动脑学物理 热学》", 31 October 1984 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102139864B (en) | Method for producing electronic-grade nitric acid | |
| CN112647085B (en) | Method for synthesizing high-purity disilane through electrocatalysis | |
| CN106698785A (en) | Coal gasification wastewater phenol and ammonia recovery process | |
| CN208275203U (en) | Organic waste gas recycling system in a kind of cyclohexanol production | |
| CN115744915B (en) | Treatment method and treatment device for chlorosilane liquid | |
| CN109999617A (en) | The technique of CO concentration in a kind of reduction low-temperature methanol washing tail-gas | |
| CN111085081A (en) | Device and method for removing hydrogen fluoride in fluorine gas | |
| CN109437234B (en) | Compound semiconductor epitaxy tail gas recycling device and method | |
| CN109078351B (en) | Defluorination chlorine tower and process and device for removing fluorine and chlorine in sulfuric acid by adopting same | |
| CN113800484A (en) | Recovery device and recovery method for nitrogen trifluoride gas in vented tail gas | |
| CN112661115B (en) | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF produced by fluorite method | |
| CN103497086A (en) | Preparation method of perfluoropropane | |
| CN204281663U (en) | The rectifying condensing works of polyurethane foam reactor is reclaimed in a kind of alcoholysis | |
| CN116641098A (en) | Pretreatment method for preparing ultrapure hydrogen and ultrapure oxygen | |
| CN113893663B (en) | Nitrogen trifluoride production sewage disposal equipment and process method | |
| KR20190054910A (en) | Method for purifying waste solvent | |
| CN112546803A (en) | Treatment system and method for cathode tail gas of nitrogen trifluoride electrolytic cell | |
| CN215627706U (en) | Device for co-producing pentafluoroethane from tetrafluoroethylene | |
| CN107335318B (en) | Hydrogen chloride recycling system and method in industrial organic waste gas | |
| CN113842753A (en) | Treatment process of tail gas discharged from cathode of nitrogen trifluoride electrolytic cell | |
| CN220578931U (en) | Nitrogen trifluoride purification system | |
| CN216778464U (en) | Laughing gas treatment device for purification process in nitrogen trifluoride production process | |
| CN102390833B (en) | Method for recycling waste chlorosilane in polycrystalline silicon, produced by using modified Siemens process under negative pressure | |
| CN217504147U (en) | Energy-conserving recovery system of polycrystalline silicon chlorosilane-containing tail gas | |
| CN210663574U (en) | Rectification purification system for low-pressure liquefied gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: 057550 No. five Weir Road, chemical industry gathering area, Feixiang District, Handan, Hebei, 1 Applicant after: China shipbuilding (Handan) Perry Special Gas Co.,Ltd. Address before: 057550 No. five Weir Road, chemical industry gathering area, Feixiang District, Handan, Hebei, 1 Applicant before: PERIC SPECIAL GASES Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20211217 |
|
| RJ01 | Rejection of invention patent application after publication |