CN113480700A - Solid asphaltene inhibitor and preparation method thereof - Google Patents
Solid asphaltene inhibitor and preparation method thereof Download PDFInfo
- Publication number
- CN113480700A CN113480700A CN202110746319.9A CN202110746319A CN113480700A CN 113480700 A CN113480700 A CN 113480700A CN 202110746319 A CN202110746319 A CN 202110746319A CN 113480700 A CN113480700 A CN 113480700A
- Authority
- CN
- China
- Prior art keywords
- solid asphaltene
- asphaltene inhibitor
- solid
- asphaltene
- inhibitor
- 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.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
- C08F283/006—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polymers provided for in C08G18/00
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/49—Phosphorus-containing compounds
- C08K5/51—Phosphorus bound to oxygen
- C08K5/53—Phosphorus bound to oxygen bound to oxygen and to carbon only
- C08K5/5317—Phosphonic compounds, e.g. R—P(:O)(OR')2
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L95/00—Compositions of bituminous materials, e.g. asphalt, tar, pitch
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Civil Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
Abstract
The invention discloses a solid asphaltene inhibitor, which comprises the following raw materials in proportion: 50-70 parts of epoxy resin modified waterborne polyurethane, 20-35 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 10-23 parts of ammonium persulfate and 5-17 parts of p-styrene sulfonic acid. The invention also discloses a preparation method of the solid asphaltene inhibitor. The solid asphaltene inhibitor is adsorbed or embedded into an asphaltene lamellar molecular structure, so that the oriented accumulation of the asphaltene is disturbed, and the asphaltene is not easy to aggregate and deposit; and has high inhibition rate and inhibition effect.
Description
Technical Field
The invention relates to the field of oilfield chemicals, and particularly relates to a solid asphaltene inhibitor and a preparation method thereof.
Background
Asphaltenes refer to components of crude oil that are insoluble in low molecular weight alkanes (especially n-pentane and n-heptane), but soluble in aromatic hydrocarbon solvents (such as toluene and benzene). Asphaltene precipitation often occurs in the process of oil exploitation and gathering and transportation, which brings difficulty to reservoir and ground gathering and transportation. The main action mechanism of the transport of the asphaltene in a shaft or a pipeline is Brownian diffusion, the deposition speed is slow, deposited particles are loose, and the asphaltene is easy to dissolve again or transport together with fluid under proper conditions; if the flow regime of the fluid is generally in the case of pipe flow, the deposition mechanism is a combination of brownian diffusion, rayleigh diffusion, collision, etc., and the deposition rate is influenced by the flow rate. The research on petroleum system considers that Zhejiang blue matter molecules form micelles through self-association, and then the micelles aggregate into larger aggregates to form flocs. Asphaltene deposition can generally be divided into several steps: precipitation, aggregation, surface contact and adhesion, some of the macromolecular asphaltenes may also adsorb directly to the contact surface.
In order to solve the problem of asphaltene precipitation, researchers develop different kinds of asphaltene inhibitors, and research on low-molecular-weight amphiphilic inhibitors including aliphatic alkylbenzene sulfonic acid, para-alkylphenol, fatty acid and the like is carried out, and the capabilities of dispersing and inhibiting asphaltene coagulation are compared. In addition, ionic liquids, polymer chemicals, vegetable oils, proprietary commercial dispersants (consisting of a mixture of dispersants), and the like, have also been tested for their potential application in oil field applications and have all been shown to have certain inhibition properties.
PBTCA (1,2, 4-tricarboxylic acid-2-phosphonic butane) is used as a nontoxic and pollution-free low-phosphorus chelating agent and a scale inhibitor, and is widely applied to corrosion and scale inhibition of industrial circulating cooling water devices and other petrochemical industries. But the invention is not applied to the research of asphaltene inhibitors, and the invention uses ammonium persulfate as an initiator, epoxy resin modified waterborne polyurethane as a copolymer, 1,2, 4-tricarboxylic acid-2-phosphonic acid butane as a compound agent, and p-styrene sulfonic acid as a dispersant, and adopts a polymerization and compound synchronous mode to obtain the solid asphaltene inhibitor, thereby having better inhibition effect.
Disclosure of Invention
Accordingly, the present invention is directed to a solid asphaltene inhibitor capable of inhibiting precipitation, aggregation, surface contact and adhesion of asphaltenes.
The technical scheme of the invention is realized as follows:
a solid asphaltene inhibitor comprising the starting material 1,2, 4-tricarboxylic acid-2-phosphonobutane.
The technical scheme is that the inhibitor comprises epoxy resin modified waterborne polyurethane, ammonium persulfate and p-styrene sulfonic acid.
The further technical scheme is that the inhibitor comprises the following raw materials in proportion: 50-70 parts of epoxy resin modified waterborne polyurethane, 20-35 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 10-23 parts of ammonium persulfate and 5-17 parts of p-styrene sulfonic acid.
The preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on epoxy resin modified waterborne polyurethane, 1,2, 4-tricarboxylic acid-2-phosphonic butane, ammonium persulfate and styrene sulfonic acid, and then carrying out drying and shearing to prepare the solid asphaltene inhibitor.
The further technical proposal is that the melt blending is carried out for 4 to 6 hours under the temperature condition of 75 to 80 ℃ by stirring and reaction.
The further technical scheme is that the stirring speed is 300-500 r/min.
The further technical scheme is that the drying and shearing are carried out for 2-4h under the condition of 45-55 ℃ and then for 1-2h under the condition of 45-55 ℃.
The further technical scheme is that the shear rate is 500-2000 r/min.
The further technical proposal is that the finished product granularity of the solid asphaltene inhibitor is 50-100 μm.
The further technical proposal is that the weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 50-200.
Compared with the prior art, the invention has the beneficial effects that:
(1) the raw material epoxy resin adopted by the invention is a polyhydroxy compound, can directly react with-NCO groups, and the epoxy resin is introduced to the main chain of the waterborne polyurethane to form a partial network structure, so that the performance is more excellent; in addition, the epoxy resin also contains epoxy groups, the epoxy groups have high reactivity and are easy to generate ring-opening reaction, and a more compact net-shaped three-dimensional structure is easy to form by combining with the 1,2, 4-tricarboxylic acid-2-phosphonic butane, so that the epoxy resin is adsorbed or embedded into an asphaltene sheet molecular structure, the oriented accumulation of the asphaltene is disturbed, and the asphaltene is difficult to aggregate and deposit.
(2) The solid asphaltene inhibitor is compounded with the 1,2, 4-tricarboxylic acid-2-phosphonic butane, and the phosphonic acid group on the solid asphaltene inhibitor helps the asphaltene inhibitor to be adsorbed on rocks, so that the precipitation, aggregation, surface contact and adhesion of the asphaltene are further prevented.
(3) The solid asphaltene inhibitor has high inhibition rate, and the inhibition rate of the asphaltene can reach more than 90% after 50min by experiments in an asphaltene toluene solution.
Detailed Description
For clear and complete description of the technical solutions in the present invention, it is obvious that the inventor combines the embodiments to describe, but the following embodiments describe only some embodiments of the present invention, not all 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.
Example 1
The solid asphaltene inhibitor comprises the following raw materials in proportion: 50 parts of epoxy resin modified waterborne polyurethane, 20 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 10 parts of ammonium persulfate and 5 parts of p-styrene sulfonic acid.
Example 2
The solid asphaltene inhibitor comprises the following raw materials in proportion: 70 parts of epoxy resin modified waterborne polyurethane, 35 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 23 parts of ammonium persulfate and 17 parts of p-styrene sulfonic acid.
Example 3
The solid asphaltene inhibitor comprises the following raw materials in proportion: 60 parts of epoxy resin modified waterborne polyurethane, 30 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 15 parts of ammonium persulfate and 12 parts of p-styrene sulfonic acid.
Example 4
A solid asphaltene inhibitor, the formulation of the inhibitor material being the same as in example 1.
The preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on epoxy resin modified waterborne polyurethane, 1,2, 4-tricarboxylic acid-2-phosphonic butane, ammonium persulfate and p-styrene sulfonic acid at the temperature of 75 ℃, and carrying out stirring reaction for 4 hours, wherein the stirring speed is 300 r/min; and then drying and shearing, specifically drying for 2h at 45 ℃, and shearing for 1h at 45 ℃ to prepare the solid asphaltene inhibitor. The shear rate was 500 r/min. The finished product granularity of the solid asphaltene inhibitor is 50 mu m. The weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 50.
Example 5
A solid asphaltene inhibitor, the formulation of the inhibitor material being the same as in example 2.
The preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on epoxy resin modified waterborne polyurethane, 1,2, 4-tricarboxylic acid-2-phosphonic acid butane, ammonium persulfate and p-styrene sulfonic acid at the temperature of 80 ℃, and carrying out stirring reaction for 6 hours, wherein the stirring speed is 500 r/min; and then drying and shearing, specifically drying for 4h at 55 ℃, and shearing for 2h at 55 ℃ to prepare the solid asphaltene inhibitor. The shear rate was 2000 r/min. The finished product granularity of the solid asphaltene inhibitor is 100 mu m. The weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 200.
Example 6
A solid asphaltene inhibitor, the formulation of the inhibitor material being the same as in example 3.
The preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on epoxy resin modified waterborne polyurethane, 1,2, 4-tricarboxylic acid-2-phosphonic acid butane, ammonium persulfate and p-styrene sulfonic acid at the temperature of 78 ℃, and carrying out stirring reaction for 5 hours, wherein the stirring speed is 400 r/min; and then drying and shearing, specifically drying for 3h at 50 ℃, and shearing for 1.5h at 50 ℃ to prepare the solid asphaltene inhibitor. The shear rate was 1000 r/min. And the particle size of the finished product of the solid asphaltene inhibitor is 80 mu m by drying and shearing. The weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 100.
Comparative example 1
The difference from example 4 is that the epoxy-modified aqueous polyurethane was replaced with polyacrylate. The method specifically comprises the following steps: the preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on polyacrylate, 1,2, 4-tricarboxylic acid-2-phosphonic acid butane, ammonium persulfate and p-styrene sulfonic acid at the temperature of 75 ℃, and carrying out stirring reaction for 4 hours, wherein the stirring speed is 300 r/min; and then drying and shearing, specifically drying for 2h at 45 ℃, and shearing for 1h at 45 ℃ to prepare the solid asphaltene inhibitor. The shear rate was 500 r/min. The finished product granularity of the solid asphaltene inhibitor is 50 mu m. The weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 50.
Comparative example 2
In contrast to example 4, 1,2, 4-tricarboxylic acid-2-phosphonobutane was replaced by aminotrimethylenephosphonic acid. The method specifically comprises the following steps: the preparation method of the solid asphaltene inhibitor comprises the steps of carrying out melt blending on epoxy resin modified waterborne polyurethane, amino trimethylene phosphonic acid, ammonium persulfate and p-styrene sulfonic acid at the temperature of 75 ℃, and carrying out stirring reaction for 4 hours, wherein the stirring speed is 300 r/min; and then drying and shearing, specifically drying for 2h at 45 ℃, and shearing for 1h at 45 ℃ to prepare the solid asphaltene inhibitor. The shear rate was 500 r/min. The finished product granularity of the solid asphaltene inhibitor is 50 mu m. The weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 50.
Inhibition experiments
The experimental principle is as follows: adding the solid asphaltene inhibitor into an asphaltene (mass m) toluene solution (the mass ratio of the asphaltene to the toluene is 1:5000), gradually dripping n-heptane to flocculate the asphaltene, reducing the concentration of the asphaltene in the solution, allowing the asphaltene to begin to aggregate and precipitate, taking out the precipitated asphaltene after 30, 40 and 50min, drying at 70 deg.C for 30min, weighing m1The asphaltene inhibition ratio is: { (m-m)1)/m}×100％。
The effect of the inhibitor on inhibiting the deposition of asphaltenes can be evaluated on the basis of the change in the amount of asphaltene deposition after the inhibitor is added.
TABLE 1
As shown in Table 1, the asphaltene inhibition ratios of examples 4 to 6 are 82.5 to 86.3% after 30min, 82.5 to 86.3% after 40min, and 82.5 to 86.3% after 50min, and it can be seen that the asphaltene inhibitor of the solid asphaltene inhibitor of the present invention reaches 90% or more after 50min, reflecting that the solid asphaltene inhibitor of the present invention has a high inhibition rate.
As can be seen from comparison between example 4 and comparative example 1, although polyacrylate is also a polar resin, the asphaltene inhibition ratio of the prepared solid asphaltene inhibitor is significantly lower than that of the solid asphaltene inhibitor prepared from epoxy resin modified aqueous polyurethane.
As can be seen from comparison of example 4 with comparative example 2, aminotrimethylene phosphonic acid also contains phosphonic acid groups, but the asphaltene inhibition ratio of the prepared solid asphaltene inhibitor is significantly lower than that of the solid asphaltene inhibitor prepared from 1,2, 4-tricarboxylic acid-2-phosphonobutane.
It can be seen that the inhibitor prepared by the method is related to the formation of a more compact reticular three-dimensional structure by combining the epoxy resin modified waterborne polyurethane with a part of reticular structure and the epoxy resin also containing epoxy groups, wherein the epoxy groups have high reactivity and are easy to generate ring-opening reaction, and the 1,2, 4-tricarboxylic acid-2-phosphonic acid butane is used for adsorbing or embedding the inhibitor into the molecular structure of an asphaltene sheet layer, so that the oriented accumulation of the asphaltene is disturbed, and the asphaltene is not easy to aggregate and deposit.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. A solid asphaltene inhibitor characterized by: the inhibitor comprises the starting material 1,2, 4-tricarboxylic acid-2-phosphonobutane.
2. The solid asphaltene inhibitor according to claim 1, wherein: the inhibitor raw materials also comprise epoxy resin modified waterborne polyurethane, ammonium persulfate and p-styrene sulfonic acid.
3. A solid asphaltene inhibitor according to claim 2, characterized in that: the inhibitor comprises the following raw materials in proportion: 50-70 parts of epoxy resin modified waterborne polyurethane, 20-35 parts of 1,2, 4-tricarboxylic acid-2-phosphonic butane, 10-23 parts of ammonium persulfate and 5-17 parts of p-styrene sulfonic acid.
4. The method for preparing a solid asphaltene inhibitor according to any one of claims 1 to 3, characterized in that: the epoxy resin modified waterborne polyurethane, 1,2, 4-tricarboxylic acid-2-phosphonic acid butane, ammonium persulfate and styrene sulfonic acid are subjected to melt blending, drying and shearing to prepare the solid asphaltene inhibitor.
5. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the melt blending is carried out for 4 to 6 hours under the condition of the temperature of 75 to 80 ℃ and stirring reaction.
6. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the stirring speed is 300-500 r/min.
7. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the drying and shearing are carried out by drying for 2-4h at 45-55 ℃ and shearing for 1-2h at 45-55 ℃.
8. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the shear rate is 500-2000 r/min.
9. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the finished product granularity of the solid asphaltene inhibitor is 50-100 mu m.
10. The method for preparing a solid asphaltene inhibitor according to claim 4, characterized in that: the weight ratio of the solid asphaltene inhibitor to the crude oil is 1: 50-200.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110746319.9A CN113480700B (en) | 2021-07-01 | 2021-07-01 | Solid asphaltene inhibitor and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110746319.9A CN113480700B (en) | 2021-07-01 | 2021-07-01 | Solid asphaltene inhibitor and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113480700A true CN113480700A (en) | 2021-10-08 |
| CN113480700B CN113480700B (en) | 2022-06-14 |
Family
ID=77940032
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110746319.9A Active CN113480700B (en) | 2021-07-01 | 2021-07-01 | Solid asphaltene inhibitor and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113480700B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101215464A (en) * | 2007-12-27 | 2008-07-09 | 大庆石油学院 | Bottom hole sedimentation type anti-scaling anti-wax agent |
| US20120067579A1 (en) * | 2010-09-20 | 2012-03-22 | S.P.C.M. Sa | Process for enhanced oil recovery using the asp technique |
| CN106350047A (en) * | 2016-08-18 | 2017-01-25 | 中国石油化工股份有限公司 | Corrosion inhibitor for oil-gas fields and preparation method of corrosion inhibitor |
| CN106520103A (en) * | 2016-09-27 | 2017-03-22 | 中国石油天然气股份有限公司 | Scale remover for long-acting pressure reduction and injection increase of water injection well and preparation method thereof |
-
2021
- 2021-07-01 CN CN202110746319.9A patent/CN113480700B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101215464A (en) * | 2007-12-27 | 2008-07-09 | 大庆石油学院 | Bottom hole sedimentation type anti-scaling anti-wax agent |
| US20120067579A1 (en) * | 2010-09-20 | 2012-03-22 | S.P.C.M. Sa | Process for enhanced oil recovery using the asp technique |
| CN106350047A (en) * | 2016-08-18 | 2017-01-25 | 中国石油化工股份有限公司 | Corrosion inhibitor for oil-gas fields and preparation method of corrosion inhibitor |
| CN106520103A (en) * | 2016-09-27 | 2017-03-22 | 中国石油天然气股份有限公司 | Scale remover for long-acting pressure reduction and injection increase of water injection well and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| DEMADIS, KD，等: "Chemistry of organophosphonate scale growth inhibitors: 3. Physicochemical aspects of 2-phosphonobutane-1,2,4-tricarboxylate (PBTC) and its effect on CaCO3 crystal growth", 《BIOINORGANIC CHEMISTRY AND APPLICATIONS》 * |
| 陈亚联，等: "延长油田代表性区块清、污水配伍技术及储层敏感性研究", 《中国优秀硕士学位论文全文数据库 (工程科技Ⅰ辑)》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113480700B (en) | 2022-06-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Atta et al. | Demulsification of heavy crude oil using new nonionic cardanol surfactants | |
| Atta et al. | Effect of different families of hydrophobic anions of imadazolium ionic liquids on asphaltene dispersants in heavy crude oil | |
| US8357745B2 (en) | Wax-containing materials | |
| Zhou et al. | Synthesis and property study of ter-copolymer P (MA-AMPS-HPA) scale inhibitor | |
| CN110452677A (en) | One kind is based on modified MoS2The method for preparing drag reducer | |
| CN105037903A (en) | Wax-bearing crude oil rheological aid | |
| EP2300744A1 (en) | Drag reducing compositions and methods of manufacture and use | |
| CN113480700B (en) | Solid asphaltene inhibitor and preparation method thereof | |
| AU2014376202A1 (en) | Composition and method for oilfield water clarification processes | |
| Tan et al. | Synergistic inhibition effect and mechanism of polycation and polyanion on colloidal silica | |
| EP4301827A1 (en) | Chemical additives for enhancing the performance of friction reducer solution and its applications thereof | |
| Chen et al. | Synthesis, aggregation behavior of alternating copolymer emulsifier in oil solution and its application in oil-based drilling fluids | |
| EP2197990A2 (en) | Additive useful for stabilizing crude oil | |
| Kabel et al. | Synthesis and evaluation of PAMAM dendrimer and PDPF-b-POP block copolymer as asphaltene inhibitor/dispersant | |
| Shi et al. | Synthesis, characterization and scale inhibition performance evaluation of novel dendrimers with the initiator core of pentaerythritol derivative | |
| EP1668098A1 (en) | Drag reducing agents for multiphase flow | |
| US11884891B2 (en) | Environmentally friendly flow improvers with improved formulation stability at low temperatures | |
| CN115558533B (en) | Naphthalene dispersant for preparing nano hydrocarbon fuel and application thereof | |
| CN109679613B (en) | Foam drainage agent composition and preparation method and application thereof | |
| Zhang et al. | Preparation of a novel flocculant and its performance for treating acidic oily wastewater | |
| CN109971448B (en) | Twin-chain surfactant type thickened oil viscosity reducer | |
| CN114656044B (en) | Environment-friendly nano fluid scale inhibitor and preparation method and application thereof | |
| CN110330956B (en) | Environment-friendly polyamino acid viscosity reducer for drilling fluid and preparation method thereof | |
| CN110283580B (en) | Pour point depressing and paraffin inhibitor and its prepn | |
| CN113563857B (en) | Alloy material for surface tension treatment of thickened oil and application method thereof |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |