CN111039788A - Environment-friendly efficient natural gas hydrate inhibitor - Google Patents
Environment-friendly efficient natural gas hydrate inhibitor Download PDFInfo
- Publication number
- CN111039788A CN111039788A CN201911300018.2A CN201911300018A CN111039788A CN 111039788 A CN111039788 A CN 111039788A CN 201911300018 A CN201911300018 A CN 201911300018A CN 111039788 A CN111039788 A CN 111039788A
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- CN
- China
- Prior art keywords
- natural gas
- gas hydrate
- hydrate inhibitor
- polyester polyol
- hyperbranched polyester
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
- C07C69/66—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety
- C07C69/67—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety of saturated acids
- C07C69/675—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety of saturated acids of saturated hydroxy-carboxylic acids
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
- C09K8/524—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning organic depositions, e.g. paraffins or asphaltenes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/005—Pipe-line systems for a two-phase gas-liquid flow
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/02—Pipe-line systems for gases or vapours
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2208/00—Aspects relating to compositions of drilling or well treatment fluids
- C09K2208/22—Hydrates inhibition by using well treatment fluids containing inhibitors of hydrate formers
Abstract
The invention belongs to the technical field of chemical industry, and relates to an environment-friendly and efficient natural gas hydrate inhibitor which comprises hyperbranched polyester polyol, wherein the hyperbranched polyester polyol is obtained by polymerizing a plurality of 2, 2-dimethylolpropionic acids. The hyperbranched polyester polyol is substituted by a hydrophobic or hydrophilic substituent group on the terminal hydroxyl group, and the biodegradable and nontoxic hyperbranched polyester polyol is modified, so that the hyperbranched polyester polyol and the surface of a hydrate form interaction, and the hyperbranched polyester polyol can be used as a natural gas hydrate inhibitor. Because the nontoxic 2, 2-dimethylolpropionic acid is adopted, the treatment is not needed in the processes of transportation, use and the like, and no environmental pollution, personal damage and safety accidents are caused; in addition, the process does not need to be modified, and the existing alcohol injection process can be fully utilized. Therefore, the natural gas hydrate inhibitor is a nontoxic, degradable and low-dose dynamic hydrate inhibitor, is safe, environment-friendly and economical, and can efficiently control the generation of natural gas hydrate.
Description
Technical Field
The invention belongs to the technical field of chemical industry, relates to a dynamic hydrate inhibitor, and particularly relates to an environment-friendly and efficient natural gas hydrate inhibitor.
Background
Natural gas hydrates are ice-like crystalline substances formed from natural gas and water under high pressure and low temperature conditions. In the oil and gas production process, natural gas hydrate is a potential hazard and can be formed in a shaft, a pipeline, equipment and the like, so that the shaft, the pipeline, the equipment and the like are frozen and blocked, and even shut-down and production stop are performed in severe cases. Thus, operators need to use hydrate inhibitors to remove hydrates, prevent hydrate formation or prevent hydrate particle agglomeration.
Conventional hydrate inhibitors are largely divided into thermodynamic and kinetic inhibitors. A thermodynamic hydrate inhibitor is a chemical substance that shifts the thermodynamic equilibrium of a hydrate to a lower temperature. Currently, the most common thermodynamic inhibitors are methanol and monoethylene glycol, and methanol as a traditional thermodynamic hydrate inhibitor causes great harm to personnel and environment due to the high toxicity of the thermodynamic hydrate inhibitor, so that the thermodynamic hydrate inhibitor can not meet the requirements of safe, environment-friendly and low-cost development of oil and gas fields. They are added at very high concentrations, 10-60% relative to the concentration of water, and therefore often require regeneration and recycling. The use of low dose inhibitors to replace thermodynamic inhibitors such as methanol has been studied at home and abroad since the 90 s.
The kinetic inhibitor is mostly a water-soluble or water-dispersible polymer, inhibits the formation of hydrate only in a water phase, does not influence the thermodynamic condition of the hydrate, and is more effective than the thermodynamic inhibitor in a low-concentration system. Since the kinetic inhibitor mainly exerts an inhibitory action on the formation or growth of hydrate crystals, prolongs the induction time of hydrate nucleation or changes the aggregation process of the crystals, thereby inhibiting the formation of hydrates, the polymers constituting the dynamic hydrate inhibitor tend to contain amide groups which make them polar, and hydrocarbon chains adjacent to or directly linked to the amides; atomic absorption spectroscopy does not prevent the formation of hydrate particles, but prevents agglomeration of hydrate particles. However, if the low dosage of the inhibitor is adopted in the prior art, the cost of the existing alcohol inhibitor matching equipment is high; at the same time, kinetic inhibitors are also dependent on different process parameters, such as supercooling, pressure, fluid composition, etc.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide an environment-friendly and efficient natural gas hydrate inhibitor which can replace methanol, is a nontoxic, degradable and low-dose gas hydrate inhibitor and can effectively inhibit the generation of natural gas hydrate.
The purpose of the invention is realized by the following technical scheme:
the environment-friendly efficient natural gas hydrate inhibitor comprises hyperbranched polyester polyol, wherein the hyperbranched polyester polyol is obtained by carrying out polymerization reaction on 2, 2-dimethylolpropionic acid through a formula (1), and in the formula (1), n is an integer larger than 1.
Further, the hyperbranched polyester polyol has a plurality of hydroxyl end groups, which can be esterified with at least one hydrophilic group or hydrophobic group.
Further, the hydrophobic group is generated by reacting the hyperbranched polyester polyol with carboxylic acid and/or carboxylic anhydride.
Further, the carboxylic acid is any one of pivalic acid, dimethylbutyric acid, trimethylpentanoic acid, tert-butyltrimethylpentanoic acid, diethylhexanoic acid and cyclopentanecarboxylic acid.
Further, the carboxylic anhydride is trimethylacetic anhydride.
Further, the hydrophobic group is an aliphatic or aromatic substituent group, and the chain length is between C1 and C40.
Further, the hydrophobic group is any one of pentyl, butyl, pentyl isomer or butyl isomer.
Further, the hydrophilic group is an acid functional group.
Further, the composite material also comprises a synergist which is matched with the hyperbranched polyester polyol for use; the synergist is at least one of n-butyl alcohol, chitosan, 2-butoxyethanol, propanol, polysuccinimide, diethylene glycol monomethyl ether and non-polymer surfactant containing caprolactam or alkylamine head group.
In addition, the invention also provides application of the environment-friendly and efficient natural gas hydrate inhibitor, which is suitable for an oil-gas-water three-phase or gas-water two-phase coexistence system.
Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects: the molecular structure of the natural gas hydrate inhibitor is hyperbranched polyester polyol, the hyperbranched polyester polyol is obtained by polymerizing 2, 2-dimethylolpropionic acid, the hyperbranched polymer is a polymer which radially extends in space, and each repeating unit has a potential branch point instead of forming a long chain like the traditional linear polymer; the hyperbranched polyester polyol is substituted by a hydrophobic or hydrophilic substituent group on the terminal hydroxyl group, and the biodegradable and nontoxic hyperbranched polyester polyol is modified, so that the hyperbranched polyester polyol and the surface of a hydrate form interaction, and the hyperbranched polyester polyol can be used as a natural gas hydrate inhibitor. The hydrate inhibitor is non-toxic due to the use of non-toxic 2, 2-dimethylolpropionic acid. Therefore, the treatment is not needed in the processes of transportation, use and the like, and no environmental pollution, personal damage and safety accidents are caused; in addition, the process does not need to be modified, and the existing alcohol injection process can be fully utilized. Therefore, the natural gas hydrate inhibitor provided by the invention is a nontoxic, degradable and low-dose dynamic hydrate inhibitor, is safe, environment-friendly and economical, and can efficiently control the generation of natural gas hydrate.
Detailed Description
The exemplary embodiments will be described herein in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention.
In order to make those skilled in the art better understand the technical solution of the present invention, the present invention is further described in detail with reference to the following examples.
Example 1:
the invention provides an environment-friendly efficient natural gas hydrate inhibitor which comprises hyperbranched polyester polyol, wherein the hyperbranched polyester polyol is obtained by carrying out polymerization reaction on 2, 2-dimethylolpropionic acid through a formula (1), and in the formula (1), n is an integer larger than 1.
Wherein, the structural formula of the 2, 2-dimethylolpropionic acid (DMPA) is shown as a formula (2), and the monomer is a nontoxic biodegradable low molecular compound; the hyperbranched polymer has a plurality of hydroxyl end groups (-OH), is easy to form hydrogen bonds, and the end groups can be modified into amphipathic (hydrophilic and hydrophobic) groups with different degrees, so that the hyperbranched polymer has good interaction with the surface of a hydrate.
Further, the hyperbranched polyester polyol has a plurality of hydroxyl end groups, and can be substituted by hydrophobic or hydrophilic substituent groups, so that the hyperbranched polymer and the surface of the hydrate form interaction to inhibit the formation of the hydrate; the hydroxyl end group can be subjected to esterification reaction with at least one hydrophilic group or hydrophobic group, and can be esterified with the hydrophilic group, so that the water solubility of the hyperbranched polymer can be increased, and the interaction between the hyperbranched polymer and a hydrate can be increased by esterification with the hydrophobic group.
Further, the hydrophobic group is generated by reacting the hyperbranched polyester polyol with carboxylic acid and/or carboxylic anhydride.
Further, the carboxylic acid is any one of pivalic acid, dimethylbutyric acid, trimethylpentanoic acid, tert-butyltrimethylpentanoic acid, diethylhexanoic acid and cyclopentanecarboxylic acid.
Further, the carboxylic anhydride is trimethylacetic anhydride.
Further, the hydrophobic group is an aliphatic or aromatic substituent group, and the chain length is between C1 and C40.
Preferably, the hydrophobic group is any one of pentyl, butyl, pentyl isomer or butyl isomer.
Preferably, the hydrophilic group is an acid functional group.
Further, the composite material also comprises a synergist which is matched with the hyperbranched polyester polyol for use; the synergist is at least one of n-butyl alcohol, chitosan, 2-butoxyethanol, propanol, polysuccinimide, diethylene glycol monomethyl ether and non-polymer surfactant containing caprolactam or alkylamine head group.
In addition, the invention also provides application of the environment-friendly and efficient natural gas hydrate inhibitor, which is suitable for an oil-gas-water three-phase or gas-water two-phase coexistence system.
The environment-friendly efficient natural gas hydrate inhibitor NT-GHI provided by the invention is a nontoxic, degradable and low-dose kinetic hydrate inhibitor, is safe, environment-friendly and economical, can efficiently control the generation of natural gas hydrate, and has the advantages of being embodied in the following aspects: (1) low dose: the dosage of the inhibitor is greatly lower than that of a thermodynamic inhibitor, the inhibitor can be effective when the dosage is 0.5-2%, and 1% of the anti-agglomerant is equivalent to 25% of the dosage of methanol; (2) no need of harmless treatment: because the nontoxic 2, 2-dimethyl propionic acid is adopted, the hydrate inhibitor is nontoxic, and therefore, the hydrate inhibitor does not need to be treated in the processes of transportation, use and the like; (3) the existing gas collection process does not need to be modified: the process does not need to be modified, and the existing alcohol injection process can be fully utilized; (4) and no environmental pollution, personal injury and safety accident are caused. Therefore, the natural gas hydrate inhibitor NT-GHI provided by the invention can completely replace methanol.
Example 2:
the invention provides an environment-friendly and efficient natural gas hydrate inhibitor, which is verified to have an inhibiting effect on a hydrate through four groups of tests, wherein the specific test process is as follows:
group A: 1.0g of hyperbranched polyester was dispersed by grinding in 10g of tetrahydrofuran. 0.5g of pivalic anhydride was added dropwise thereto, and the mixture was stirred at room temperature overnight. After 20 hours the solvent was evaporated from the mixture to give a clear solution. The temperature of the experimental solution before hydrate formation can reach 8 ℃, and the operating temperature of the stirring device in a condensate/brine/gas system can reach 10 ℃.
Group B: 5.0g of hyperbranched polyester was dispersed by grinding in 25g of tetrahydrofuran. 3.5g of pivalic anhydride was added dropwise thereto, and the mixture was stirred at room temperature overnight. After 20 hours the solvent was evaporated from the mixture to give a clear solution. The temperature of the experimental solution before hydrate formation reached 9 ℃.
Group C: 5.0g of hyperbranched polyester was dispersed by grinding in 25g of tetrahydrofuran. 5g of pivalic anhydride was added dropwise and stirred at room temperature overnight. After 20 hours the solvent was evaporated from the mixture to give a clear solution. The temperature of the experimental solution before hydrate formation reached 7 ℃.
Group D: 2.0g of hyperbranched polyester was dissolved by grinding with 0.04g p-toluene sulfonic acid in a small amount of methanol. The mixture was heated and reacted under toluene reflux while continuously collecting the evaporated water. The temperature of the experimental solution before hydrate formation reached 7 ℃.
In conclusion, through the four groups of tests, the test results show that the temperature of the test solution is too low by using the natural gas hydrate inhibitor provided by the invention, so that the formation of the hydrate is delayed.
Accordingly, the present invention provides such natural gas hydrate inhibitors which comprise hyperbranched polyester polyols comprising hydroxyl and carboxylic acid functional groups which can react with each other to form covalent ester bonds. The carboxylic acid is any one of trimethyl acetic acid, dimethyl butyric acid, trimethyl valeric acid, tert-butyl trimethyl valeric acid, diethyl hexanoic acid and cyclo valeric acid. Such hydrate inhibitors can be produced by preparing hyperbranched polyols based on the monomer 2, 2-dimethylpropionic acid (DMPA). In order to make the hyperbranched polymer amphiphilic, hydroxyl groups can be esterified with terminal tert-butyl valproic acid; or the terminal hydroxyl is reacted with trimethyl acetyl anhydride to prepare trimethyl acetyl substituted hyperbranched polyester.
The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention.
It is to be understood that the present invention is not limited to what has been described above, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.
Claims (10)
1. The environment-friendly efficient natural gas hydrate inhibitor is characterized by comprising hyperbranched polyester polyol, wherein the hyperbranched polyester polyol is obtained by carrying out polymerization reaction on a plurality of 2, 2-dimethylolpropionic acids through a formula (1).
2. The environmentally friendly and efficient natural gas hydrate inhibitor according to claim 1, wherein the hyperbranched polyester polyol has a plurality of hydroxyl end groups, and the hydroxyl end groups can be subjected to esterification reaction with at least one hydrophilic group or hydrophobic group.
3. The environmentally friendly and efficient natural gas hydrate inhibitor according to claim 1, wherein the hydrophobic group is generated by reacting a hyperbranched polyester polyol with a carboxylic acid and/or a carboxylic acid anhydride.
4. The environmentally friendly and efficient natural gas hydrate inhibitor according to claim 3, wherein the carboxylic acid is any one of pivalic acid, dimethylbutyric acid, trimethylpentanoic acid, tert-butyltrimethylpentanoic acid, diethylhexanoic acid and cyclopentanecarboxylic acid.
5. The environmentally friendly and efficient natural gas hydrate inhibitor according to claim 3, wherein the carboxylic anhydride is trimethylacetic anhydride.
6. The environmentally friendly and efficient natural gas hydrate inhibitor according to claim 1, wherein the hydrophobic group is an aliphatic or aromatic substituent group, and the chain length is between C1 and C40.
7. The environmentally friendly and efficient natural gas hydrate inhibitor as defined in claim 6, wherein the hydrophobic group is any one of pentyl, butyl, pentyl isomer or butyl isomer.
8. The environmentally friendly and highly effective natural gas hydrate inhibitor according to claim 1, wherein the hydrophilic group is an acid functional group.
9. The environment-friendly and efficient natural gas hydrate inhibitor according to claim 1, further comprising a synergist, wherein the synergist is used in combination with the hyperbranched polyester polyol; the synergist is at least one of n-butyl alcohol, chitosan, 2-butoxyethanol, propanol, polysuccinimide, diethylene glycol monomethyl ether and non-polymer surfactant containing caprolactam or alkylamine head group.
10. The use of the environmentally friendly and highly effective natural gas hydrate inhibitor according to any one of claims 1 to 9 in oil and gas production and gathering processes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911300018.2A CN111039788A (en) | 2019-12-16 | 2019-12-16 | Environment-friendly efficient natural gas hydrate inhibitor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911300018.2A CN111039788A (en) | 2019-12-16 | 2019-12-16 | Environment-friendly efficient natural gas hydrate inhibitor |
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| CN111039788A true CN111039788A (en) | 2020-04-21 |
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| CN201911300018.2A Pending CN111039788A (en) | 2019-12-16 | 2019-12-16 | Environment-friendly efficient natural gas hydrate inhibitor |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111499785A (en) * | 2020-04-30 | 2020-08-07 | 中海石油(中国)有限公司 | Natural gas hydrate inhibitor with hyperbranched structure and preparation method and application thereof |
| US20230272264A1 (en) * | 2021-12-28 | 2023-08-31 | Dalian University Of Technology | Environmentally friendly natural gas hydrate inhibitor and application |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150252246A1 (en) * | 2012-10-26 | 2015-09-10 | Sinvent As | Gas hydrate inhibitor, method and use of hyperbranched polyester polyols as gas hydrate inhibitors |
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2019
- 2019-12-16 CN CN201911300018.2A patent/CN111039788A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150252246A1 (en) * | 2012-10-26 | 2015-09-10 | Sinvent As | Gas hydrate inhibitor, method and use of hyperbranched polyester polyols as gas hydrate inhibitors |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111499785A (en) * | 2020-04-30 | 2020-08-07 | 中海石油(中国)有限公司 | Natural gas hydrate inhibitor with hyperbranched structure and preparation method and application thereof |
| US20230272264A1 (en) * | 2021-12-28 | 2023-08-31 | Dalian University Of Technology | Environmentally friendly natural gas hydrate inhibitor and application |
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Application publication date: 20200421 |
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