CN114456298A - Demulsifier for short-process treatment of oil-in-water emulsion in offshore oil field and preparation method thereof - Google Patents
Demulsifier for short-process treatment of oil-in-water emulsion in offshore oil field and preparation method thereof Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 44
- 239000007764 o/w emulsion Substances 0.000 title claims abstract description 35
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 78
- 230000008569 process Effects 0.000 claims abstract description 34
- 238000006243 chemical reaction Methods 0.000 claims description 47
- 238000005086 pumping Methods 0.000 claims description 39
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 36
- 238000010438 heat treatment Methods 0.000 claims description 34
- 238000003756 stirring Methods 0.000 claims description 33
- 239000008367 deionised water Substances 0.000 claims description 30
- 229910021641 deionized water Inorganic materials 0.000 claims description 30
- 239000007864 aqueous solution Substances 0.000 claims description 24
- 239000010865 sewage Substances 0.000 claims description 24
- 239000003999 initiator Substances 0.000 claims description 21
- 239000003945 anionic surfactant Substances 0.000 claims description 20
- 239000000243 solution Substances 0.000 claims description 20
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 18
- -1 alkyl propenyl carboxylate Chemical compound 0.000 claims description 18
- 239000000178 monomer Substances 0.000 claims description 18
- 229910052757 nitrogen Inorganic materials 0.000 claims description 18
- LDHQCZJRKDOVOX-UHFFFAOYSA-N 2-butenoic acid Chemical compound CC=CC(O)=O LDHQCZJRKDOVOX-UHFFFAOYSA-N 0.000 claims description 15
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims description 14
- 238000001816 cooling Methods 0.000 claims description 14
- 239000012986 chain transfer agent Substances 0.000 claims description 12
- 229920000642 polymer Polymers 0.000 claims description 12
- 239000012429 reaction media Substances 0.000 claims description 12
- 238000002156 mixing Methods 0.000 claims description 11
- 238000011049 filling Methods 0.000 claims description 10
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 claims description 9
- JIGUQPWFLRLWPJ-UHFFFAOYSA-N Ethyl acrylate Chemical compound CCOC(=O)C=C JIGUQPWFLRLWPJ-UHFFFAOYSA-N 0.000 claims description 6
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 claims description 6
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 6
- PNJWIWWMYCMZRO-UHFFFAOYSA-N pent‐4‐en‐2‐one Natural products CC(=O)CC=C PNJWIWWMYCMZRO-UHFFFAOYSA-N 0.000 claims description 6
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 claims description 5
- SUPCQIBBMFXVTL-UHFFFAOYSA-N ethyl 2-methylprop-2-enoate Chemical compound CCOC(=O)C(C)=C SUPCQIBBMFXVTL-UHFFFAOYSA-N 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 5
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 claims description 4
- GVGUFUZHNYFZLC-UHFFFAOYSA-N dodecyl benzenesulfonate;sodium Chemical compound [Na].CCCCCCCCCCCCOS(=O)(=O)C1=CC=CC=C1 GVGUFUZHNYFZLC-UHFFFAOYSA-N 0.000 claims description 4
- 229940080264 sodium dodecylbenzenesulfonate Drugs 0.000 claims description 4
- LCPVQAHEFVXVKT-UHFFFAOYSA-N 2-(2,4-difluorophenoxy)pyridin-3-amine Chemical compound NC1=CC=CN=C1OC1=CC=C(F)C=C1F LCPVQAHEFVXVKT-UHFFFAOYSA-N 0.000 claims description 3
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 3
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 3
- 229910000013 Ammonium bicarbonate Inorganic materials 0.000 claims description 3
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 claims description 3
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 claims description 3
- 235000012538 ammonium bicarbonate Nutrition 0.000 claims description 3
- 239000001099 ammonium carbonate Substances 0.000 claims description 3
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims description 3
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical compound CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 claims description 3
- JRKICGRDRMAZLK-UHFFFAOYSA-L peroxydisulfate Chemical compound [O-]S(=O)(=O)OOS([O-])(=O)=O JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 claims description 3
- 229910000028 potassium bicarbonate Inorganic materials 0.000 claims description 3
- 235000015497 potassium bicarbonate Nutrition 0.000 claims description 3
- 239000011736 potassium bicarbonate Substances 0.000 claims description 3
- TYJJADVDDVDEDZ-UHFFFAOYSA-M potassium hydrogencarbonate Chemical compound [K+].OC([O-])=O TYJJADVDDVDEDZ-UHFFFAOYSA-M 0.000 claims description 3
- USHAGKDGDHPEEY-UHFFFAOYSA-L potassium persulfate Chemical compound [K+].[K+].[O-]S(=O)(=O)OOS([O-])(=O)=O USHAGKDGDHPEEY-UHFFFAOYSA-L 0.000 claims description 3
- CHQMHPLRPQMAMX-UHFFFAOYSA-L sodium persulfate Substances [Na+].[Na+].[O-]S(=O)(=O)OOS([O-])(=O)=O CHQMHPLRPQMAMX-UHFFFAOYSA-L 0.000 claims description 3
- 238000007667 floating Methods 0.000 abstract description 5
- 239000000839 emulsion Substances 0.000 abstract description 3
- 239000002994 raw material Substances 0.000 abstract description 3
- 239000006185 dispersion Substances 0.000 abstract description 2
- 239000002893 slag Substances 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 55
- 239000010779 crude oil Substances 0.000 description 11
- 239000003814 drug Substances 0.000 description 9
- 238000007599 discharging Methods 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 238000002347 injection Methods 0.000 description 5
- 239000007924 injection Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 125000000129 anionic group Chemical group 0.000 description 4
- 238000000605 extraction Methods 0.000 description 4
- 238000005188 flotation Methods 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 241000758789 Juglans Species 0.000 description 3
- 235000009496 Juglans regia Nutrition 0.000 description 3
- 239000013543 active substance Substances 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000004090 dissolution Methods 0.000 description 3
- 239000012153 distilled water Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 230000014759 maintenance of location Effects 0.000 description 3
- 239000008239 natural water Substances 0.000 description 3
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 3
- UIIMBOGNXHQVGW-UHFFFAOYSA-M sodium bicarbonate Substances [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 3
- 235000020234 walnut Nutrition 0.000 description 3
- 230000004075 alteration Effects 0.000 description 2
- 239000003093 cationic surfactant Substances 0.000 description 2
- 229940079593 drug Drugs 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000012190 activator Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004581 coalescence Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000008398 formation water Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
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- 238000011084 recovery Methods 0.000 description 1
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- 239000013589 supplement Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
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- 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
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/04—Acids; Metal salts or ammonium salts thereof
- C08F220/06—Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
-
- 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
- C08F2/00—Processes of polymerisation
- C08F2/38—Polymerisation using regulators, e.g. chain terminating agents, e.g. telomerisation
-
- 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
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/10—Esters
- C08F220/12—Esters of monohydric alcohols or phenols
- C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
- C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
- C08F220/1802—C2-(meth)acrylate, e.g. ethyl (meth)acrylate
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G33/00—Dewatering or demulsification of hydrocarbon oils
- C10G33/04—Dewatering or demulsification of hydrocarbon oils with chemical means
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Colloid Chemistry (AREA)
Abstract
The invention provides a demulsifier for short-process oil-in-water emulsion treatment of offshore oil fields and a preparation method thereof. The demulsifier prepared by the invention has the advantages of easily available raw materials, controllable preparation process and low slag rate; the product is blue phase, small in granularity and good in stability; the product has the characteristics of good water solubility, high dispersion speed, high floating speed of separated oil drops, clear water color and the like, and is suitable for treating oil-in-water emulsions in short process of offshore oil fields.
Description
Technical Field
The invention relates to the technical field of petroleum industry, in particular to a demulsifier for treating oil-in-water emulsion in short process of offshore oil fields and a preparation method thereof.
Background
The technological measures of exploitation, separation, sewage treatment and the like of offshore oil fields are concentrated on oil extraction platforms or floating oil extraction vessels, the space is small, equipment is concentrated, oily sewage enters a sewage treatment system after being primarily separated from a three-phase separator, and the whole technological process is only twenty minutes, even has an ultrashort flow platform which is less than 3 minutes. The produced liquid of the oil field is an emulsion fluid formed by mixing trace impurities with crude oil, natural gas and formation water, enters an old oil field in the later development stage, along with the implementation of water injection measures, the water content in the produced liquid tends to rise year by year, and the water content of the produced liquid of a certain oil field in Bohai sea is up to more than 85 percent. When the produced fluid contains more than 70% of water, a part of the crude oil except the crude oil free in water is dispersed in water in the form of small droplets, and is wrapped by the water to form an oil-in-water emulsion, and the oil-in-water emulsion is required to be separated to obtain the crude oil. The old oil field which runs for ten years or decades almost reaches the upper limit of the designed productivity, and then the expansion, large-scale transformation and capacity improvement of the platform production process are almost impossible.
Disclosure of Invention
The invention overcomes the defects in the prior art, the technological measures of exploitation, separation, sewage treatment and the like of the offshore oil field are concentrated on an oil extraction platform or a floating oil extraction wheel, the space is small, the equipment is concentrated, the whole technological process is only twenty minutes, even less than 3 minutes, and therefore, the demulsifier needs to be used for treating the oil-in-water emulsion, and the demulsifier and the preparation method thereof for treating the oil-in-water emulsion in the short process of the offshore oil field are provided, the demulsifier has the advantages of easily obtained raw materials, controllable preparation process, low slag rate and good stability; the product has the characteristics of good water solubility, high dispersion speed, high floating speed of separated oil drops, clear color of separated water and the like, and when the medicine adding concentration is 30mg/L in application, the deoiling rate of the production sewage can reach 75-95%.
The purpose of the invention is realized by the following technical scheme.
A demulsifier for treating oil-in-water emulsion in short process of offshore oil field and a preparation method thereof are carried out according to the following steps:
step 1, adding deionized water into a reaction kettle, stirring, starting a vacuum pump, pumping the pressure in the kettle to-0.01 MPa, repeating the process for 3 times, closing the vacuum pump, and starting nitrogen for 30 min. All outlets are closed, and steam is started to heat up. Deionized water is adopted to dissolve the anionic surfactant to obtain 10% of anionic surfactant aqueous solution. When the temperature of the deionized water in the reaction kettle is raised to 55-65 ℃, the nitrogen is started again to supplement the pressure, so that the micro-positive pressure of 0.5-0.6MPa is formed in the kettle. Pumping the 10% anionic active agent aqueous solution into a reaction kettle by a dosing pump, and uniformly stirring to obtain a reaction medium A;
step 2, stopping heating, continuously stirring under the protection of nitrogen, naturally cooling the reaction medium A prepared in the step 1 to 25-30 ℃, and pumping lipophilic monomers into the reaction kettle, wherein the lipophilic monomers are one or more of propenyl carboxylate, styrene and alkyl propenyl carboxylate; stirring for 20-40min, pumping propenyl carboxylic acid into the kettle, and stirring for 20-40 min. Heating with steam, heating to 55-60 deg.C, pumping half of 1% aqueous solution of initiator into the reaction kettle, and heating; pumping the rest 1% of initiator aqueous solution into the reaction kettle after the temperature is raised to 60-65 ℃, continuously heating until the temperature is higher than 70 ℃, so as to initiate the reaction, stopping heating when the temperature is raised to be higher than or equal to 5 ℃ within 1min, cooling with water, controlling the temperature of the reaction kettle to be 70-80 ℃ after the reaction tends to be stable, reacting for 4-6h, and adding a chain transfer agent to obtain a polymer solution B;
step 3, dissolving the dispersing aid in deionized water to form a 10% dispersing aid aqueous solution, pumping the dispersing aid aqueous solution into the polymer solution B prepared in the step 2, and stirring at room temperature, namely 15-40 ℃ for 20-40min to obtain the demulsifier for the short-process oil-in-water emulsion treatment of the offshore oilfield;
in the demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field, the mass percent of propenyl carboxylic acid is 3-7%, the mass percent of oleophilic monomer is 3-7%, the mass percent of anionic surfactant is 0.1-0.3%, the mass percent of initiator is 0.01-0.03%, the mass percent of chain transfer agent is 10-30%, the mass percent of dispersing aid is 0.1-0.5%, and the mass percent of deionized water is 65-80%.
In step 1, sodium dodecyl sulfate or sodium dodecyl benzene sulfonate is used as the anionic surfactant.
In the step 2, the lipophilic monomer adopts propenyl carboxylic ester and alkyl propenyl carboxylic ester in the mixing mass ratio of (1-4):1 or adopts the mixing mass ratio of propenyl carboxylic ester to styrene to alkyl propenyl carboxylic ester of (1-4):1:1, the propenyl carboxylic ester adopts ethyl acrylate or butyl acrylate, the alkyl propenyl carboxylic ester adopts ethyl methacrylate or methyl methacrylate, the propenyl carboxylic acid adopts acrylic acid or methacrylic acid, the initiator adopts persulfate, sodium persulfate, ammonium persulfate or potassium persulfate, and the chain transfer agent adopts ethylene glycol or propylene glycol.
In step 3, the dispersing aid is bicarbonate, specifically sodium bicarbonate, potassium bicarbonate or ammonium bicarbonate.
The demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field is suitable for treating the oil field output liquid with the water content of 70-85 percent, the filling concentration of the demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field is 10-100mg/L, the dosage of the demulsifier is reduced by 10-30 percent, and the oil removal rate of the production sewage reaches 75-95 percent.
The beneficial effects of the invention are as follows: the demulsifier provided by the invention belongs to anionic surfactants, and the molecule contains carboxylate ion groups, so that compared with nonionic surfactants, the demulsifier has ionic activity, is easier to diffuse in water, and is easier to adsorb on the surface of oil drops in water to destroy the interfacial activity; compared with cationic surfactant, the cationic surfactant has flexible molecular structure, and can be made into various sizes, and its special processing technology can make the grain size of formed emulsion be less than 50nm, diffusion speed is quick, and the long chain can be quickly extended in water, and the added HCO3 -The oil-water interfacial tension can be reduced, so that rapid demulsification and oil drop coalescence are realized, and the sewage is cleared; the invention has the advantages of easily obtained raw materials, mild reaction and controllable process; the synthesis process of the demulsifier effectively reduces the particle size of the product, and the product has better stability, diffusivity and water solubility; the application of the demulsifier can reduce the dosage of the demulsifier of a crude oil system and the flocculant of a sewage system in the process; the oil residue skimmed after treatment is returned to the process and then treated, so that the operation of oil system equipment is not influenced; the treated sewage is injected back into the stratum without increasing the water injection pressure.
Drawings
Figure 1 is a photograph of a product of the invention.
Detailed Description
The technical solution of the present invention is further illustrated by the following specific examples.
Example 1
A preparation method of a demulsifier for oil-in-water emulsion treatment in short process of offshore oil field comprises the following steps:
(1) ensuring that a reaction kettle is cleaned, adding 600Kg of deionized water or distilled water into the reaction kettle, starting stirring, deoxidizing by using vacuum nitrogen for three times, introducing nitrogen for protection to form (0.5-0.6) MPa micro-positive pressure, and starting steam to heat; dissolving 1.5Kg of anionic surfactant sodium dodecyl sulfate with 15Kg of deionized water at the temperature of 60 ℃ to form 10% of anionic surfactant; when the temperature of the deionized water in the kettle is raised to 60 ℃, pumping 10% of the anionic active agent into the reaction kettle in one step through a medicament pump, and stirring for 1 hour to obtain a reaction medium A;
(2) under the protection of nitrogen, stopping steam heating, emptying a jacket, naturally cooling the reaction medium A, cooling to below 30 ℃, pumping 32Kg of lipophilic monomer ethyl acrylate and 10Kg of ethyl methacrylate in proportion, stirring for 30min, uniformly mixing, pumping 42Kg of hydrophilic monomer methacrylic acid in proportion, stirring for 30min, starting steam heating, and pumping 1/2 of initiator solution for the first time when the temperature is raised to (55-60) DEG C (120 g of initiator is prepared into 12Kg of aqueous solution by deionized water in situ); continuing heating, when the temperature is raised to (60-65) DEG C, pumping in the rest initiator solution for the second time, continuously heating to a temperature higher than 70 ℃ to initiate the reaction, rapidly increasing the temperature and the pressure at the moment, stopping heating when the temperature is raised to 5 ℃ within 1 minute, emptying a jacket, cooling by using natural water, reacting for 4 hours by controlling the temperature of the reaction kettle to be (70-80) DEG C until the reaction is stable, and adding 300Kg of chain transfer agent ethylene glycol to obtain a polymer solution B;
(3) 1Kg of dispersing aid NaHCO3Dissolving in deionized water to form 10Kg of aqueous solution, pumping into the polymer solution B once after complete dissolution, stirring for 30min at room temperature (15-40 ℃), discharging, filling, filtering with a 200-mesh filter bag, and discharging to obtain 1000Kg of demulsifier for oil-in-water emulsion treatment in short process of offshore oilfield.
Example 2
A preparation method of a demulsifier for oil-in-water emulsion treatment in short process of offshore oil field comprises the following steps:
(1) ensuring that a reaction kettle is cleaned, adding 1600Kg of deionized water or distilled water into the reaction kettle, starting stirring, deoxidizing by vacuum nitrogen for three times, introducing nitrogen for protection to form (0.5-0.6) MPa micro-positive pressure, and starting steam to heat; 2.6Kg of anionic surfactant, sodium dodecyl sulfate, is dissolved in 15Kg of deionized water at 60 ℃; when the temperature of the deionized water in the kettle is raised to 60 ℃, pumping the dissolved anionic activator into the reaction kettle in one step through a medicament pump, and stirring for 1h to obtain a reaction medium A;
(2) continuing under the protection of nitrogen, stopping steam heating, emptying a jacket, naturally cooling the reaction medium A, cooling to below 30 ℃, pumping 84Kg of oleophylic monomer ethyl acrylate in proportion, stirring for 30min, uniformly mixing, pumping 84Kg of hydrophilic monomer methacrylic acid in proportion, stirring for 30min, starting steam heating, and pumping 1/2 of initiator solution for the first time when the temperature is increased to (55-60) DEG C (250 g of initiator is prepared into 12Kg of aqueous solution by deionized water on site); continuing heating, when the temperature is raised to (60-65) DEG C, pumping in the rest initiator solution for the second time, continuously heating to a temperature higher than 70 ℃ to initiate the reaction, rapidly increasing the temperature and the pressure at the moment, stopping heating when the temperature is raised to 5 ℃ within 1 minute, emptying a jacket, cooling by using natural water, reacting for 4 hours by controlling the temperature of the reaction kettle to be (70-80) DEG C until the reaction is stable, and adding 200Kg of chain transfer agent ethylene glycol to obtain a polymer solution B;
(3) 2Kg of dispersing aid NaHCO3Dissolving in deionized water to form 20Kg of aqueous solution, pumping into the polymer solution B once after complete dissolution, stirring for 30min at room temperature (15-40) DEG C, discharging, filling, filtering with a 200-mesh filter bag, and discharging to obtain 2000Kg of demulsifier for oil-in-water emulsion treatment in short process of offshore oilfield.
Example 3
A preparation method of a demulsifier for oil-in-water emulsion treatment in short process of offshore oil field comprises the following steps:
(1) ensuring that a reaction kettle is cleaned, adding 7000Kg of deionized water or distilled water into the reaction kettle, starting stirring, deoxidizing by using vacuum nitrogen five times, introducing nitrogen for protection to form (0.5-0.6) MPa micro-positive pressure, and starting steam to heat; dissolving 15Kg of anionic surfactant sodium dodecyl benzene sulfonate with deionized water at 60 ℃ and 200Kg to form the anionic surfactant; when the temperature of the deionized water in the kettle is raised to 60 ℃, pumping the anionic active agent solution into the reaction kettle at one time through a medicament pump, and stirring for 2 hours to obtain a reaction medium A;
(2) under the protection of nitrogen, stopping steam heating, emptying a jacket, naturally cooling the reaction medium A, cooling to below 30 ℃, pumping 168Kg of oleophylic monomer ethyl acrylate, 84Kg of styrene and 84Kg of ethyl methacrylate in proportion, stirring for 1h, uniformly mixing, pumping 336Kg of hydrophilic monomer methacrylic acid in proportion, stirring for 1h, starting steam heating, when the temperature is increased to (55-60) DEG C, firstly pumping 1/2 of initiator solution (20 Kg of aqueous solution prepared by deionized water in situ for 1Kg of initiator), continuously heating, and when the temperature is increased to (60-65) DEG C, secondly pumping the rest of initiator solution. The reaction can be initiated when the temperature is continuously heated to be higher than 70 ℃, the temperature and the pressure are sharply increased at the moment, the heating is stopped when the temperature is increased by 5 ℃ within 1 minute, the jacket is evacuated, the temperature is reduced by adopting natural water, the reaction is finished when the reaction is stable and the temperature of the reaction kettle is controlled to be (70-80) DEG C, and 800Kg of chain transfer agent ethylene glycol is added to obtain a polymer solution B;
(3) 8Kg of dispersing aid NaHCO3Dissolving in deionized water to form 20Kg of aqueous solution, pumping into the polymer solution B once after complete dissolution, stirring for 30min at room temperature (15-40 ℃), discharging, filling, filtering with a 200-mesh filter bag, and discharging to obtain 8000Kg of demulsifier for oil-in-water emulsion treatment in short process of offshore oilfield.
Verification of Experimental examples
According to the process condition of the offshore oil field, the demulsifier for the short-process treatment oil-in-water emulsion of the offshore oil field is injected into a crude oil treatment system, the injection concentration is 10-100mg/L, the using amount of the demulsifier can be reduced by 30%, the oil removal rate of production sewage can reach more than 90%, oil drops float quickly, and water is clear.
The following are application effect cases:
the Bohai sea certain oil field FPSO (floating oil recovery vessel) has the functions of oil-gas-water treatment, storage, life and the like, the comprehensive water content of the oil field developed at present exceeds 85 percent, the sewage treatment time is only about 11min, and the oil field belongs to a short-flow oil field; meanwhile, the platform equipment is simple, and the requirement on the performance of the oil-water treatment agent is high. The oil field oil gas water treatment process system comprises a crude oil treatment system and a water treatment system, wherein the flow of the crude oil treatment system is divided into a Train1 system and a Train 2 systemThe row comprises three stages, namely a first-stage separator V-2140/V-2340 (the volume is 311.2m3) and a second-stage separator V-2160/V-2360 (the volume is 311.2m3)3) An electric dehydrator V-2190/V-2390(282.63m 3); the water treatment process has three stages, and the daily treatment capacity of the sewage is about 56000m3Mixing the sewage of each level of water phase of the crude oil separator and then entering the first level of a sewage treatment process: oil skimmer V-2610A/B/C, total volume of each separator 63m3The operation temperature is about 75 ℃, and the retention time of the sewage is about 4 min; the second stage is an air floatation separator V-2630A/B/C, and the total volume of each separator is 63m3The operation temperature is about 74 ℃, and the retention time of the sewage is about 4 min; the third stage is walnut shell filter F-26500/1/2/3/4/5, each filter has total volume of 41m3The sewage retention time is about 3 min. Table 1 lists the product residence times for each stage of the treater:
TABLE 1FPSO Sewage treatment System flow parameters and Sewage residence time
The demulsifier of the invention in the embodiment 1 is used for carrying out field pilot test in an oil field in 4 months in 2020, a medicament is injected into an inlet of a Train1 series primary separator V-2140/V-2340 of a crude oil treatment system, monitoring points are respectively positioned at an outlet of the primary separator V-2140/V-2340 of an oil system, an outlet of an oil skimmer of a water system, an outlet of an air flotation device and an outlet of walnut shells, and the specific injection conditions are shown in Table 2:
TABLE 2FPSO on-site agent specific filling
The field test is carried out for 5 days, from 21 days at 4 months to 26 days at 4 months, the water quality and oil content values of each monitoring point are respectively tested during the test period, and are compared with the recorded data during the original medicament period, and the specific water quality monitoring condition is shown in table 3:
table 3 example 1 monitoring of oil in water during testing of the inventive agents
As can be seen from table 3:
(1) crude oil system crude drug (from 4 months 21 days 17: 00 to 4 months 23 days 17: 00): v2140 has an average value of 268ppm of oil in the water phase outlet sewage; the average oil content of the sewage at the inlet of the oil skimmer is about 232 ppm;
(2) raw drug data for water treatment system (from 17: 00 on day 21/4/21 to 17: 00 on day 23/4): the average oil content of the sewage at the outlet of the oil skimmer is about 60 ppm; the average value of the oil content of the sewage at the outlet of the air flotation device is about 40 ppm;
(3) during the test (20: 00pm at 23 days 4 and 25 days 4 and 20:00), after the demulsifier is filled, the average value of oil content in each level of water in a water system is reduced, the average value of water quality at the outlet of an oil skimmer is about 54ppm, and the reduction amplitude is about 10%; the average value of the oil content of the water at the outlet of the air flotation device is about 39ppm, and the reduction amplitude is about 2.5%;
(4) after the filling amount of the medicament is reduced by 20:30pm in 25 days of 4 months and 26 days of 4 months and 11:00am, the average value of the water quality at the outlet of the oil skimmer is about 55ppm, and the reduction amplitude is about 8.3%; the average value of the oil content of the water at the outlet of the air flotation device is 38ppm, and the reduction range is about 5 percent.
(5) During the test period, the water quality and the water injection value of the walnut shell outlet are kept stable.
(6) By optimizing the filling amount of the reverse demulsifier, the filling amount is adjusted from 800mL/min to 750m/min, the filling amount is adjusted by about 6.3 percent, and the field process is stable.
The invention being thus described by way of example, it should be understood that any simple alterations, modifications or other equivalent alterations as would be within the skill of the art without the exercise of inventive faculty, are within the scope of the invention.
Claims (10)
1. The demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field is characterized by comprising the following components in parts by weight: the method comprises the following steps:
step 1, adding deionized water into a reaction kettle, stirring, starting a vacuum pump, pumping the pressure in the kettle to-0.01 MPa, repeating the process for 3 times, closing the vacuum pump, starting nitrogen for 30min, closing all outlets, starting steam for heating, dissolving an anionic surfactant by using the deionized water to obtain a 10% anionic surfactant aqueous solution, starting nitrogen for pressure compensation when the temperature of the deionized water in the reaction kettle is raised to 55-65 ℃, so that micro-positive pressure of 0.5-0.6MPa is formed in the kettle, pumping the 10% anionic surfactant aqueous solution into the reaction kettle by using a dosing pump, and uniformly stirring to obtain a reaction medium A;
step 2, stopping heating, continuously stirring under the protection of nitrogen, naturally cooling the reaction medium A prepared in the step 1 to 25-30 ℃, and pumping lipophilic monomers into the reaction kettle, wherein the lipophilic monomers are one or more of propenyl carboxylate, styrene and alkyl propenyl carboxylate; stirring for 20-40min, pumping propenyl carboxylic acid into the kettle, stirring for 20-40min, heating with steam, heating to 55-60 deg.C, pumping half of 1% initiator aqueous solution into the reaction kettle, and continuing heating; pumping the rest 1% of initiator aqueous solution into the reaction kettle after the temperature is raised to 60-65 ℃, continuously heating until the temperature is higher than 70 ℃, so as to initiate the reaction, stopping heating when the temperature is raised to be higher than or equal to 5 ℃ within 1min, cooling with water, controlling the temperature of the reaction kettle to be 70-80 ℃ after the reaction tends to be stable, reacting for 4-6h, and adding a chain transfer agent to obtain a polymer solution B;
step 3, dissolving the dispersing aid in deionized water to form a 10% dispersing aid aqueous solution, pumping the dispersing aid aqueous solution into the polymer solution B prepared in the step 2, and stirring at room temperature, namely 15-40 ℃ for 20-40min to obtain the demulsifier for the short-process oil-in-water emulsion treatment of the offshore oilfield;
in the demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field, the mass percent of propenyl carboxylic acid is 3-7%, the mass percent of oleophilic monomer is 3-7%, the mass percent of anionic surfactant is 0.1-0.3%, the mass percent of initiator is 0.01-0.03%, the mass percent of chain transfer agent is 10-30%, the mass percent of dispersing aid is 0.1-0.5%, and the mass percent of deionized water is 65-80%.
2. The demulsifier for oil-in-water emulsion short-flow treatment of offshore oilfield according to claim 1, wherein: in step 1, sodium dodecyl sulfate or sodium dodecyl benzene sulfonate is used as the anionic surfactant.
3. The demulsifier for oil-in-water emulsion short-flow treatment of offshore oilfield according to claim 1, wherein: in the step 2, the lipophilic monomer adopts propenyl carboxylic ester and alkyl propenyl carboxylic ester in the mixing mass ratio of (1-4):1 or adopts the mixing mass ratio of propenyl carboxylic ester to styrene to alkyl propenyl carboxylic ester of (1-4):1:1, the propenyl carboxylic ester adopts ethyl acrylate or butyl acrylate, the alkyl propenyl carboxylic ester adopts ethyl methacrylate or methyl methacrylate, the propenyl carboxylic acid adopts acrylic acid or methacrylic acid, the initiator adopts persulfate, sodium persulfate, ammonium persulfate or potassium persulfate, and the chain transfer agent adopts ethylene glycol or propylene glycol.
4. The demulsifier for short-process oil-in-water emulsion treatment of offshore oilfield according to claim 1, wherein the demulsifier comprises: in step 3, the dispersing aid is bicarbonate, specifically sodium bicarbonate, potassium bicarbonate or ammonium bicarbonate.
5. A preparation method of a demulsifier for oil-in-water emulsion treatment in short process of offshore oil field is characterized by comprising the following steps: the method comprises the following steps:
step 1, adding deionized water into a reaction kettle, stirring, starting a vacuum pump, pumping the pressure in the kettle to-0.01 MPa, repeating the process for 3 times, closing the vacuum pump, starting nitrogen for 30min, closing all outlets, starting steam for heating, dissolving an anionic surfactant by using the deionized water to obtain a 10% anionic surfactant aqueous solution, starting nitrogen for pressure compensation when the temperature of the deionized water in the reaction kettle is raised to 55-65 ℃, so that micro-positive pressure of 0.5-0.6MPa is formed in the kettle, pumping the 10% anionic surfactant aqueous solution into the reaction kettle by using a dosing pump, and uniformly stirring to obtain a reaction medium A;
step 2, stopping heating, continuously stirring under the protection of nitrogen, naturally cooling the reaction medium A prepared in the step 1 to 25-30 ℃, and pumping lipophilic monomers into the reaction kettle, wherein the lipophilic monomers are one or more of propenyl carboxylate, styrene and alkyl propenyl carboxylate; stirring for 20-40min, pumping propenyl carboxylic acid into the kettle, stirring for 20-40min, heating with steam, heating to 55-60 deg.C, pumping half of 1% initiator aqueous solution into the reaction kettle, and continuing heating; pumping the rest 1% of initiator aqueous solution into the reaction kettle after the temperature is raised to 60-65 ℃, continuously heating until the temperature is higher than 70 ℃, so as to initiate the reaction, stopping heating when the temperature is raised to be higher than or equal to 5 ℃ within 1min, cooling with water, controlling the temperature of the reaction kettle to be 70-80 ℃ after the reaction tends to be stable, reacting for 4-6h, and adding a chain transfer agent to obtain a polymer solution B;
step 3, dissolving the dispersing aid in deionized water to form a 10% dispersing aid aqueous solution, pumping the dispersing aid aqueous solution into the polymer solution B prepared in the step 2, and stirring at room temperature, namely 15-40 ℃ for 20-40min to obtain the demulsifier for the short-process oil-in-water emulsion treatment of the offshore oilfield;
in the demulsifier for oil-in-water emulsion treatment in short process in offshore oilfield, the mass percent of propenyl carboxylic acid is 3-7%, the mass percent of lipophilic monomer is 3-7%, the mass percent of anionic surfactant is 0.1-0.3%, the mass percent of initiator is 0.01-0.03%, the mass percent of chain transfer agent is 10-30%, the mass percent of dispersing aid is 0.1-0.5%, and the mass percent of deionized water is 65-80%.
6. The preparation method of the demulsifier for oil-in-water emulsion in short-flow treatment of offshore oilfield according to claim 5, wherein the demulsifier comprises: in step 1, sodium dodecyl sulfate or sodium dodecyl benzene sulfonate is used as the anionic surfactant.
7. The preparation method of the demulsifier for oil-in-water emulsion in short-flow treatment of offshore oilfield according to claim 5, wherein the demulsifier comprises: in the step 2, the mixing mass ratio of propenyl carboxylate and alkyl propenyl carboxylate is adopted as the oleophilic monomer (1-4):1 or the mixing mass ratio of propenyl carboxylate, styrene and alkyl propenyl carboxylate is adopted as (1-4):1:1, ethyl acrylate or butyl acrylate is adopted as propenyl carboxylate, ethyl methacrylate or methyl methacrylate is adopted as alkyl propenyl carboxylate, acrylic acid or methacrylic acid is adopted as propenyl carboxylic acid, persulfate, sodium persulfate, ammonium persulfate or potassium persulfate is adopted as initiator, and ethylene glycol or propylene glycol is adopted as chain transfer agent.
8. The preparation method of the demulsifier for oil-in-water emulsion in short-flow treatment of offshore oilfield according to claim 5, wherein the demulsifier comprises: in step 3, the dispersing aid is bicarbonate, specifically sodium bicarbonate, potassium bicarbonate or ammonium bicarbonate.
9. The demulsifier for oil-in-water emulsion short-flow treatment of offshore oilfield according to any one of claims 1 to 4, wherein the application time of the demulsifier in the offshore oilfield production platform process flow is 5 to 20 min.
10. Use according to claim 9, characterized in that: the demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field is suitable for treating the oil field output liquid with the water content of 70-85 percent, the filling concentration of the demulsifier for treating the oil-in-water emulsion in the short process of the offshore oil field is 10-100mg/L, the using amount of the demulsifier is reduced by 10-30 percent, and the oil removal rate of the production sewage reaches 75-95 percent.
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| EP0260108A1 (en) * | 1986-09-08 | 1988-03-16 | Exxon Research And Engineering Company | Hydrophobically functionalized cationic polymers |
| CN109734835A (en) * | 2018-12-05 | 2019-05-10 | 中海油天津化工研究设计院有限公司 | A kind of acrylic acid ester emulsion reverse-phase emulsifier and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0260108A1 (en) * | 1986-09-08 | 1988-03-16 | Exxon Research And Engineering Company | Hydrophobically functionalized cationic polymers |
| CN109734835A (en) * | 2018-12-05 | 2019-05-10 | 中海油天津化工研究设计院有限公司 | A kind of acrylic acid ester emulsion reverse-phase emulsifier and preparation method thereof |
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