CN102093880B - Water control agent for oil well and preparation method thereof - Google Patents
Water control agent for oil well and preparation method thereof Download PDFInfo
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- CN102093880B CN102093880B CN2010106100414A CN201010610041A CN102093880B CN 102093880 B CN102093880 B CN 102093880B CN 2010106100414 A CN2010106100414 A CN 2010106100414A CN 201010610041 A CN201010610041 A CN 201010610041A CN 102093880 B CN102093880 B CN 102093880B
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Abstract
The invention relates to a water control agent for an oil well and a preparation method thereof. The method comprises the steps of: mixing sorbitan monooleate, a hydrophobic monomer and an oil phase solvent to form a continuous phase; adding ammonium persulfate serving as an oxidant into acrylamide and 2-acrylamido-2-methyl propane sulfonic acid serving as comonomers, and dissolving into water together to form a dispersed phase; adding the dispersed phase into the continuous phase to form inverse emulsion; and dripping a reducing agent, namely sodium hydrogen sulfite into the inverse emulsion step by step, and raising the temperature to initiate polymerization, wherein a generated terpolymer can be taken as the water control agent for the oil well and can also be taken as a water control fracturing thickener for the oil well. The product is simple in preparation technology; reaction conditions are easy to control; and the water control agent for the oil well is particularly suitable for water control and oil production increase of waterside or high-water-content and low-permeability oil reservoirs.
Description
Technical field
The present invention relates to a kind of oil well control aqua and preparation method thereof, relate in particular to a kind of nearly water or high moisture LOW PERMEABILITY RESERVOIR oil well control water or pressure break control aqua of being used for.
Background technology
Control water or well stimulation transformation and effective output of controlling water at nearly water and high moisture reservoir, be a difficult problem always.The big water gaging of recovery well output; Usually can cause oil offtake to descend rapidly and recover the oil to consume energy increasing; The increase that a large amount of water treatments bring production cost, also can cause shake out, some other problems such as corrosion and fouling, make recovery well be compelled to close a well in advance because of no the economic exploitation value.Since 1997; The U.S. to moisture greater than 60% well; Use the treatment solution that changes the relative permeability characteristic fracturing yield increasing measures to reform has been carried out on a plurality of stratum such as Pernran Basin, Kansas, Argentina, effectively reduce the output of water, increased oil yield; And post-processed expense, remarkable benefit have been reduced.At present, the most of east oilfields of China have got into the middle and later periods of exploitation, and oil well is in high saturation state; And in the new hydrocarbon exploration resource, have the limit at the bottom of water low-permeability oilfield proportion increasing.In this type formation fracturing raising the output transformation process, the crack often becomes the circulation passage of water at the bottom of invalid injection water or the limit, and moisture rapid rising even water logging after the pressure break will be transformed for the wellfracturing raising the output and brought great risk.
Carrying out " steady oil control water " is the important channel of improving the oil-field development benefit.Selecting to control efficiently aqua is the key that oil well is implemented the water and oil control measure, and external associated mechanisms is devoted to ooze mutually research and the application that improves water control technique always.At present, ooze the improvement system mutually and be high-molecular weight polymer, tensio-active agent (wettability reversal) or crosslinked polymer system (gel or weak gel) mostly, and be applied, have certain control water effect at scene, high oil impregnate field.But in the low-permeability oilfield use; Some problems below main the existence: (1) LOW PERMEABILITY RESERVOIR reservoir properties is poor, susceptibility is strong, have the trigger pressure gradient, and high molecular polymer or cross-linking system viscosity is big; Injection pressure is high, is prone to the clogging raw oil seepage channel and causes reservoir damage; (2) wettability reversal technology construction cost is high, and the control water cycle is short, and effect is difficult to control; (3) the domestic foreign minister research of oozing the improvement system stresses to ooze reservoir selective water shut-off and scene or shop experiment effect assessment at height mostly.
CN101476452A (CN200910020940.6) discloses a kind of water-control fracturing yield increasing method for oil gas well, is when pressing crack construction, adopts chemical degradation to coat the mode of stopping up; At underground formation plugged zone; It is characterized in that: the chemical reaction weight proportion is: 1000 parts in water, 20～40 parts of paraffin or Microcrystalline Waxes, 180～360 parts in English sand; 3～4 parts of viscosifying agents; 7～9 parts of linking agents, 0.29～6.6 part of additive, (2) construction technology step is: 1., in the dressing machine the paraffin of 50#～70# or Microcrystalline Wax heating and melting; With silica sand according to paraffin or Microcrystalline Wax: the weight ratio of silica sand=1: 4.5～18 adds in paraffin or the Microcrystalline Wax, and cooling forms and encapsulates propping agent in the dressing machine then; 2., in the container that has pump circulation or whisking appliance, add a certain amount of water, open pump circulation or whisking appliance then, slowly add viscosifying agent, add additive again after, continue the pump circulation or stirred 30 minutes, make liquid mixing abundant, form mixing solutions.3., the mixing solutions and the linking agent that 2. step are formed mix formation frozen glue spearhead according to volume ratio at 100: 0.7.4., frozen glue spearhead that 3. step is formed mixes according to weight ratio with the propping agent that encapsulates that 1. step forms at 100: 30, after stirring, with being pumped into the purpose stratum.
Summary of the invention
To the shortcoming that prior art exists, the present invention provides a kind of oil well control aqua and preparation method thereof.
Technical scheme of the present invention is following:
A kind of oil well control aqua is formed by following feedstock production:
A, external phase: be dissolved in the oil phase solvent by sorbitan monooleate (Span80) and hydrophobic monomer and make, the mass volume ratio of hydrophobic monomer and oil phase solvent is 1.0-5.0%, and unit is a grams per milliliter; The mass volume ratio of sorbitan monooleate and oil phase solvent is 5.0-8.0%, and unit is a grams per milliliter;
Said hydrophobic monomer is selected from N, N-DMAA, methyl acrylate, TEB 3K, N-vinyl acetamide, N-vinyl-N-methylacetamide, N-vinyl formamide or N-vinyl-2-Pyrrolidone;
B, disperse phase: with acrylic amide and 2-acrylamido-2-methyl propane sulfonic acid is comonomer, and ammonium persulphate is an oxygenant, common soluble in water making; The mass ratio of acrylic amide and 2-acrylamido-2-methyl propane sulfonic acid is (85-95): (5-15).
The oil phase in the above-mentioned external phase and the volume ratio of the water in the disperse phase are 3: (2-5);
Disperse phase added in the external phase stir, emulsification gets reversed-phase emulsion, regulating reversed-phase emulsion pH value is 7-8, adding reductive agent sodium sulfite anhy 96 is warmed up to 30-70 ℃ of initiated polymerization, the reaction times is 5-12h.It is 10-40% that acrylic amide and 2-acrylamido in the polymerization system-2-methyl propane sulfonic acid total monomer accounts for solution quality concentration, and ammonium persulphate and sodium sulfite anhy 96 redox initiator total mass concentration are the 0.05-0.5% of said monomer total mass.
From reactant, collect the terpolymer that generates at last, be oil well control aqua.
According to the present invention, preferred, described oil phase is kerosene or white oil.The oxygenant ammonium persulphate mol ratio that adds in said reductive agent sodium sulfite anhy 96 and the disperse phase is 1: (3-6).
The inventive method product terpolymer has following structure:
The content of hydrophobic grouping and hydrophilic radical obtains through elemental analysis method in the above-mentioned terpolymer.Wherein, preferred, hydrophobic grouping and hydrophilic radical mass percent are respectively at 3-4% and 7-8%.
According to the present invention, a kind of preparation method of oil well control aqua comprises the steps:
1,, constitutes external phase with sorbitan monooleate, hydrophobic monomer and oil phase solvent proportional mixing; Feed nitrogen deoxygenation 1-5h;
2,2-acrylamido-2-methyl propane sulfonic acid is dissolved in the water, adds acrylic amide again, the adding ammonium persulphate is an oxygenant, common formation disperse phase soluble in water; Logical nitrogen deoxygenation 1-5h;
3, be added dropwise to disperse phase in the external phase gradually and stirring fast, rotating speed is 800-1200r/min, forms reversed-phase emulsion, and adjusting reversed-phase emulsion pH value is 7-8;
4, the reversed-phase emulsion system is changed in the water bath with thermostatic control; Rotating speed is that 800-1200r/min stirs 20-30min fast, then rotating speed is transferred to 400-600r/min, in the reversed-phase emulsion system, drips the reductive agent sodium sulfite anhy 96 while stirring; Be warmed up to 30-70 ℃ of initiated polymerization; Reaction times is 5-12h, gets white size emulsus reaction product terpolymer, as oil well control aqua liquid product.
Further, above-mentioned gained white size emulsus reaction product is no longer reduced up to washed product weight with ethanol or washing with acetone 3-5 time, last 40 ℃ of vacuum-drying 5-10h, the terpolymer powder, be oil well control aqua solid phase prod.
Preferably, above-mentioned reductive agent sodium sulfite anhy 96 is mixed with the aqueous solution adding of mass concentration 0.1-0.5%.The aqueous solution that the oxygenant ammonium persulphate is mixed with mass concentration 1-3% adds.
The application of oil well control aqua of the present invention is used for nearly water or high moisture LOW PERMEABILITY RESERVOIR oil well control water or pressure break control water viscosifying agent.
Product preparation process of the present invention is simple; Easily-controlled reaction conditions; Can change that the reservoir profit oozes characteristic mutually or the part water blockoff has reached the control WOR; The product dissolution rate is fast simultaneously, has characteristics such as good anti-shearing property, thermostability, salt resistance, adsorptivity and frictional resistance are low, is particularly useful for nearly water or the measure of high moisture LOW PERMEABILITY RESERVOIR water-control oil-increasing.
Compared with present technology, the present invention has following beneficial effect:
1, the terpolymer that makes of the inventive method, productive rate are up to 70-95%, and hydrophobic grouping and hydrophilic radical content can be as required in adjustment in a big way in the product.Hydrophobic grouping and hydrophilic radical content can be regulated through the additional proportion of 2-acrylamido-2-methyl propane sulfonic acid in hydrophobic monomer and the step 2 in the control aqua preparation method step 1.
2, the white size emulsus reaction product dissolution rate of the acquisition of the oil well control aqua preparation method step 4 among the present invention is fast, can directly be used for the measure of on-the-spot control water.
Embodiment
Come the present invention is described further below in conjunction with specific embodiment, but the present invention's scope required for protection is not limited to the related scope of embodiment.The percentage concentration of ammonium persulfate solution, sodium sulfite solution is mass percent among the embodiment.
Embodiment 1
In the 250ml four-hole boiling flask that whisking appliance, tap funnel, logical nitrogen tube, TM are housed, add 40ml kerosene, add 3.2g Span80 and 0.6g methyl acrylate, dissolving is the logical nitrogen deoxygenation 5h in back fully, is mixed with external phase.
Beaker is put in the mixture of ice and water; Measure the 60ml deionized water and pour in the beaker, take by weighing 0.3g 2-acrylamido-2-methyl propane sulfonic acid and be added to and be stirred to it in the beaker and dissolve fully, regulate pH value 7-9; Taking by weighing the 11.1g acrylic amide then is added to and is stirred to it in the beaker and dissolves fully; Measure 0.9ml 2% ammonium persulfate solution and be added in the beaker, stirring mixes it, and logical nitrogen deoxygenation 5h is mixed with disperse phase.
At mixing speed is under the 1000-1200r/min condition, is added dropwise to external phase to disperse phase, and 10-30min dropwises, and forms reversed-phase emulsion, regulates pH value 7-9.
The reversed-phase emulsion system is changed in 40 ℃ of waters bath with thermostatic control, continue 1000r/min and stir 30min fast, rotating speed transfers to 400r/min then; And in system, adding 4ml 0.1% sodium sulfite solution, reaction begins, 40 ℃ of temperature of reaction; Stopped reaction behind the 6h obtains thickness oyster white latex.
The latex that obtains dropwise is added drop-wise in the acetone of 300ml, and after stirring 30min, room temperature leaves standstill 5h, wait to precipitate complete back collecting precipitation, put into 30 ℃ of dry 72h of vacuum drying oven, obtain the white copolymer powder, be product oil well control aqua of the present invention.
Product yield is near 95%, and the product property viscosity number is 543ml/g.
The white copolymer that takes a morsel powder obtains hydrophobic grouping and hydrophilic radical content in the product through elemental analysis method, and the result shows that the hydrophobic grouping of product in the present embodiment and hydrophilic radical mass percent are respectively 2.5% and 7.5%.
Embodiment 2
Of embodiment 1, different is to add 1.2ml 2% ammonium persulfate solution, adds 6ml 0.1% sodium sulfite solution, obtains product yield 72%, and the product property viscosity number is 343ml/g.It is respectively 3.0% and 7..2% that ultimate analysis gets in the product hydrophobic grouping and hydrophilic radical mass percent.
Embodiment 3
Of embodiment 1, different is 50 ℃ of temperature of reaction.Final product yield 80%, product property viscosity number are 843ml/g.Ultimate analysis gets that hydrophobic grouping and hydrophilic radical mass percent are respectively 3.4% and 7.6% in the product.
The experiment of control water:
Embodiment 1-3 products therefrom is used for oil well control water effect; Can be according to the static experimental arrangement that flows of the oil and gas industry standard SY/T5358-94 of the People's Republic of China sandstone formation rock core; Reservoir rock hole profit permeability variation obtained relevant data such as table 1 before and after the control aqua was injected in test:
Table 1
Can find out that by table 1 product of the present invention has and reduces water phase permeability significantly, reach more than 70% that and less to the permeability to oil influence, fall is controlled in 20%, has good control water effect.
Claims (7)
1. oil well control aqua is characterized in that being formed by following feedstock production:
A, external phase: be dissolved in the oil phase solvent by sorbitan monooleate and hydrophobic monomer and make, the mass volume ratio of hydrophobic monomer and oil phase solvent is 1.0-5.0%, and unit is a grams per milliliter; The mass volume ratio of sorbitan monooleate and oil phase solvent is 5.0-8.0%, and unit is a grams per milliliter; Described hydrophobic monomer is methyl acrylate or TEB 3K;
B, disperse phase: with acrylic amide and 2-acrylamido-2-methyl propane sulfonic acid is comonomer, and ammonium persulphate is an oxygenant, common soluble in water making; The mass ratio of acrylic amide and 2-acrylamido-2-methyl propane sulfonic acid is (85-95): (5-15);
The oil phase in the above-mentioned external phase and the volume ratio of the water in the disperse phase are 3: (2-5);
Disperse phase added in the external phase stir, emulsification gets reversed-phase emulsion, regulating reversed-phase emulsion pH value is 7-8, adding reductive agent sodium sulfite anhy 96 is warmed up to 30-70 ℃ of initiated polymerization, the reaction times is 5-12h; It is 10-40% that acrylic amide and 2-acrylamido in the polymerization system-2-methyl propane sulfonic acid total monomer accounts for solution quality concentration, and ammonium persulphate and sodium sulfite anhy 96 redox initiator total mass concentration are the 0.05-0.5% of said monomer total mass; From reactant, collect the terpolymer that generates, be oil well control aqua.
2. oil well control aqua according to claim 1 is characterized in that described oil phase is kerosene or white oil.
3. oil well control aqua according to claim 1 is characterized in that the oxygenant ammonium persulphate mol ratio in said reductive agent sodium sulfite anhy 96 and the disperse phase is 1: (3-6).
4. the preparation method of each said oil well control aqua of claim 1-3 comprises the steps:
(1), constitutes external phase with sorbitan monooleate, hydrophobic monomer and oil phase solvent proportional mixing; Feed nitrogen deoxygenation 1-5h;
(2) 2-acrylamido-2-methyl propane sulfonic acid is dissolved in the water, adds acrylic amide again, the adding ammonium persulphate is an oxygenant, common formation disperse phase soluble in water; Logical nitrogen deoxygenation 1-5h;
(3) be added dropwise to disperse phase in the external phase gradually and stirring fast, rotating speed is 800-1200r/min, forms reversed-phase emulsion, and adjusting reversed-phase emulsion pH value is 7-8;
(4) the reversed-phase emulsion system is changed in the water bath with thermostatic control; Rotating speed is that 800-1200r/min stirs 20-30min fast, then rotating speed is transferred to 400-600r/min, in the reversed-phase emulsion system, drips the reductive agent sodium sulfite anhy 96 while stirring; Be warmed up to 30-70 ℃ of initiated polymerization; Reaction times is 5-12h, gets white size emulsus reaction product terpolymer, is oil well control aqua liquid product.
5. like the preparation method of the said oil well control of claim 4 aqua; It is characterized in that further; Gained white size emulsus reaction product is no longer reduced up to washed product weight with ethanol or washing with acetone 3-5 time; Last 40 ℃ of vacuum-drying 5-10h get the terpolymer powder, are oil well control aqua solid phase prod.
6. like the preparation method of the said oil well control of claim 4 aqua, it is characterized in that said reductive agent sodium sulfite anhy 96 is mixed with the aqueous solution adding of mass concentration 0.1-0.5%.
7. like the preparation method of the said oil well control of claim 4 aqua, it is characterized in that said oxygenant ammonium persulphate is mixed with the aqueous solution adding of mass concentration 1-3%.
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| CN102604608A (en) * | 2011-10-19 | 2012-07-25 | 中国石油化工股份有限公司 | Water shutoff agent for extra-low permeability oil reservoir |
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| CN106543353A (en) * | 2015-09-23 | 2017-03-29 | 中国石油天然气股份有限公司 | A kind of polymer thickening agent and its preparation method and application |
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| CN106008803B (en) * | 2016-05-26 | 2018-08-03 | 中国石油集团渤海钻探工程有限公司 | A kind of high temperature resistant cross-linked acid thickening agent and preparation method thereof |
| CN106256870A (en) * | 2016-07-20 | 2016-12-28 | 天津中油渤星工程科技有限公司 | A kind of fluid loss additive for boring fluid and preparation method thereof |
| CN110699055B (en) * | 2019-10-28 | 2021-11-23 | 中国石油集团渤海钻探工程有限公司 | Plugging composition suitable for medium-small leakage plugging |
| CN113185630B (en) * | 2021-04-22 | 2022-11-01 | 四川川庆井下科技有限公司 | Biodegradable salt-tolerant thickening system and preparation method and application thereof |
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