CN1251856A - Usage of gel particles - Google Patents
Usage of gel particles Download PDFInfo
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- CN1251856A CN1251856A CN 98120664 CN98120664A CN1251856A CN 1251856 A CN1251856 A CN 1251856A CN 98120664 CN98120664 CN 98120664 CN 98120664 A CN98120664 A CN 98120664A CN 1251856 A CN1251856 A CN 1251856A
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Abstract
An oil-repelling gel particle used in oil field is prepared from unsaturated vinyl amide, unsaturated vinyl carboxylic acid, cross-linking agent, persulfate and water through stirring while dissolving, polymerizing cross-linking reaction, baking, breaking and sieving. Said gel particles can be used to repel oil in water injection well. Its performance can be controlled in reaction process. Its size can be controlled based on production condition. It serves to block big hole in the area near well, change liquid flow direction in deep oil stratum and enlarge the wave and volume of injected water for higher productivity.
Description
The invention belongs to the profile adjustment and oil displacement microgel particle of oil field displacement of reservoir oil gel product technical field, particularly a kind of precrosslink.
Well water is the serious problems that waterflooding oil field faces.In order to reduce the well water amount, avoid injecting the poor efficiency circulation of water, it is a kind of common method that adjustment intake profile technology adopts treatment agent that oil reservoir is carried out the deep processing, and wherein polyacrylamide/organic chromium frozen glue and colloidal dispersed gel become the focus of people's research.United States Patent (USP) (US 4974477 and US 4413680) is studied polyacrylamide/organic chromium and polyacrylamide/inorganic delayed cross-linking system, this frozen glue is a kind of body gel, by ground temperature underground crosslinked, gel formation is prepared multiple factor affecting such as water, pH value, difficult control, injection technology and on-the-spot preparation are complicated, and the polymkeric substance use range is between 1000～3000mg/L.Colloidal dispersed gel is the deep fluid diversion agent by the development of U.S. Tiorco oil company, it is by the high molecular polymer of lower concentration and linking agent is crosslinked forms, used linking agent is a Tiorco 677, the trivalent organic chromium, tetravalence zirconium etc., used polymkeric substance is high-molecular weight water-soluble polymers (molecular weight 900～3,100 ten thousand), working concentration is 100～1200mg/L, at this concentration range interpolymer is dispersion gel, this gel becomes adhesive tape part harshness, chocking-up degree is low, be not suitable for macropore and fissured oil reservoir, resistance to extreme temperature has only 90 degrees centigrade, and the reaction times is slow.In addition, for underground crosslinked system, in the amendment injection process, in case the balance that keeps when breaking water filling, along with the migration of amendment in thick oil pay, the reallocation of oil reservoir internal pressure makes constantly hyposmosis position migration in thick oil pay of amendment, thereby will cause serious injury to non-zone of interest, sometimes even make thick oil pay deep profile controlling failure.
The objective of the invention is to: a kind of pre-crosslinked gel particulate is provided, make gel be processed into solia particle in ground precrosslink, be used for the water injection well profile adjustment and oil displacement, the performance of gel can be controlled in reaction process, and particle size can be controlled according to working condition, can stop up macropore in the immediate vicinity of wellbore, has the fluid diversion effect in the oil reservoir deep, enlarge to inject the swept volume of water, improve recovery ratio, and injection technology and blending process are simple.
The present invention is a kind of purposes of microgel particle, and the preparation raw material of this microgel particle comprises: (A) (B) (C) N-N methylene base bisacrylamide 5.0 * 10 of thiazolinyl unsaturated carboxylic acid 6～50 parts (weight part) of thiazolinyl unsaturated amides 40～150 parts (weight part)
-5～5.0 * 10
-3Part (weight part) is 300～450 parts in water of persulfate initiator amount (E) (weight part) (D)
Said components is through stirring and dissolving, and gel is made in the reaction of generation polymerization crosslinking, and pulverize the oven dry back, sieves, and promptly obtains the microgel particle of adjustable grain; This microgel particle is used for the water injection well profile adjustment and oil displacement.
The preferred version of this programme is, the thiazolinyl unsaturated amides is an acrylamide in the preparation raw material of above-mentioned microgel particle, and the thiazolinyl unsaturated carboxylic acid is a vinylformic acid, and persulphate is an ammonium persulphate, comprising:
(A) 150 parts of acrylamides (weight part)
(B) 30 parts in vinylformic acid (weight part)
(C) N-N methylene base bisacrylamide 1.8 * 10
-3Part (weight part)
(D) 0.5 part of ammonium persulphate (weight part)
(E) 320 parts in water (weight part)
Technical scheme of the present invention can also be: a kind of purposes of microgel particle, and the preparation raw material of this microgel particle comprises:
(A) 50～150 parts of thiazolinyl unsaturated amides (weight part)
(B) N-N methylene base bisacrylamide 5 .0 * 10
-5～5.0 * 10
-3Part (weight part)
(C) persulfate initiator amount
(D) 350～450 parts in water (weight part)
Said components is through stirring and dissolving, and gel is made in the reaction of generation polymerization crosslinking, and pulverize the oven dry back, sieves, and promptly obtains the microgel particle of adjustable grain; This microgel particle is used for the water injection well profile adjustment and oil displacement.
The preferred version of this scheme is: the thiazolinyl unsaturated amides is an acrylamide in the preparation raw material of above-mentioned microgel particle, the thiazolinyl unsaturated carboxylic acid is a vinylformic acid, persulphate is a Potassium Persulphate, comprising: (A) (B) (C) N-N methylene base bisacrylamide 1.5 * 10 of anhydrous sodium carbonate 15 parts (weight part) of acrylamide 150 parts (weight part)
-3Part (weight part) be (E) 350 parts in water (weight part) of Potassium Persulphate 0.5 part (weight part) (D)
Above-mentioned microgel particle both can carry by the water injection well injection by water, also can carry by recovery well with oil and inject.Particulate carries the injection recovery well with oil, and the particulate that enters oil reservoir during oil well production does not expand effect, can not form effective obstruction to oil reservoir, and for water layer, particulate is met water and expanded, and has the selective water shut-off effect.
This microgel particle carries out crosslinking reaction on ground, reaction process is controlled easily, and process for processing is easy, adopts and injects water or oily as transport fluid, and injection technology is simple.By sieving the size that to control diameter of particle, be applicable to different geologic conditions.
After this microgel particle enters the stratum, a part remains in interior formation of hole of immediate vicinity of wellbore and stops up, viscoelastic deformation takes place in a part under the bigger water injection pressure effect in immediate vicinity of wellbore, the surplus oil in the displacement porous medium is migrated to recovery well, plays certain oil displacement efficiency; In the oil reservoir deep, because differential pressure action is less, its reactive force can't reach the required reactive force of fine migration, microgel particle will be detained formation and stop up in the oil reservoir deep, thereby forcing afterwards injection water to form in the oil reservoir deep streams, improve the swept volume that injects water, play the effect of deep fluid diversion.
The well that carries out handling in the deep at present usually is the long water injection well of water injection time, they have often formed the water drive macropore greater than tens times in original aperture even hundreds of times, thereby make reservoir heterogeneity even more serious, the tracer agent result of study shows, the water drive macropore generally only accounts for water injection well and penetrates out thickness 1%～5%, but these most permeable zones usually absorb the water injection rate of this well more than 90%, enter principle (can particulate enter porous medium and meet " 1/3rd bridge formations are theoretical ") according to the particulate selectivity, when using microgel particle, if can correctly select the matching relationship of particle diameter and pore throat, not only can make microgel particle near the borehole of shaft bottom, have selectivity and enter ability, and can make microgel particle when the inner migration of oil reservoir, not injure oil reservoir.
Enumerate the several non-limiting specific embodiment below, the present invention is further illustrated.
The purposes of 1. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises: (A) (B) (C) N-N methylene base bisacrylamide 5.0 * 10 of vinylformic acid 6 parts (weight part) of acrylamide 40 parts (weight part)
-5Part (weight part) be (E) 450 parts in water (weight part) of ammonium persulphate 0.4 part (weight part) (D)
Said components is through stirring and dissolving, and logical nitrogen 15 minutes is heated to 70 ℃, and the polymerization crosslinking reaction takes place, and makes gel, and pulverize the oven dry back, with the screening of 250 purpose screen clothes, promptly obtains the microgel particle that particle diameter is 0.062mm; This microgel particle is used for the water injection well profile adjustment and oil displacement.
Carry out the imitation oil displacement experiment experiment with this microgel particle, water is as transport fluid, be injected into the fill out sand tube that length is 30cm, being filled with particle diameter in the fill out sand tube is 0.84mm quartz sand, the pressure change in its different injection stages as shown in Figure 1, the fs is the water drive stage before transferring among the figure, and pressure is basicly stable, and subordinate phase is for annotating the grain stage, the general trend of pressure is continuous rising, but exist than great fluctuation process, fluctuate to due to the fine migration, the phase III is the water filling stage, pressure is totally on a declining curve, but also have bigger fluctuation, fluctuation is due to the migration of particle in hole and venturi, and it is particulate effusive result from core that pressure descends.Also can be observed particle from effluent flows out.Experiment showed, that this microgel particle has the effect of stopping up duct and migration.
The described microgel particle of present embodiment is carried out oil displacement experiment, the fill out sand tube that adopts is the same, experiment is preceding earlier with oily saturated core, carry out the water drive experiment again, carry out oil displacement experiment when water drive to moisture 0.8% the particulate annotated again 98% time, experimental result shows that microgel particle has displacement of reservoir oil effect preferably, can reduce the water drive residual oil saturation in the stratum greatly, see Table 1.
Table 1
The purposes of 2. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises:
| The core numbering | Recovery percent of reserves after the water drive (%) | Gel drives back recovery percent of reserves (%) | Gel drives back recovery percent of reserves increment (%) |
| ????1# | ????62 | ????88 | ????16 |
| ????2# | ????64 | ????89 | ????15 |
(A) 150 parts of acrylamides (weight part)
(B) vinylformic acid-30 part (weight part)
(C) N-N methylene base bisacrylamide 1.5 * 10
-3Part (weight part)
(D) 0.15 part of Potassium Persulphate (weight part)
(E) 320 parts in water (weight part)
(F) 40 parts (weight part) of organic sodium soil
Said components is through stirring and dissolving, and logical nitrogen 15 minutes is heated to 70 ℃, and the polymerization crosslinking reaction takes place, and makes gel, and pulverize the oven dry back, with the screening of 100 purpose screen clothes, promptly obtains the microgel particle that particle diameter is 0.149mm; This microgel particle is used for the water injection well profile adjustment and oil displacement.
We have proved that by experiment particulate has the selective water shut-off effect.Particulate in the present embodiment is injected into the fill out sand tube that length is 30cm, being filled with particle diameter in the fill out sand tube is 0.84mm quartz sand, carries out water drive and oil respectively and drives experiment, measures the pipe internal pressure and changes and mapping, as shown in Figure 2, the fs is that oil drives the stage among the figure, and it is constant that pressure keeps, and illustrates that particulate does not have ponding to oil, subordinate phase is the water drive stage, pressure rises very fast, illustrates that particulate has obvious ponding to water, and the breakthrough pressure of particulate reaches 8Mpa/m.
Additive can increase particulate intensity, and present embodiment adopts organic sodium soil as additive, and the additive of selecting according to the performance requriements and the packing variety thereof of microgel particle can also be in addition: inorganic salt, cement, flyash etc.
The purposes of 3. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises:
(A) 150 parts of acrylamides (weight part)
(B) 50 parts in vinylformic acid (weight part)
(C) N-N methylene base bisacrylamide 5.0 * 10
-3Part (weight part)
(D) 0.5 part of Potassium Persulphate (weight part)
(E) 300 parts in water (weight part)
The purposes of 4. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises:
(A) 120 parts of acrylamides (weight part)
(B) 30 parts in vinylformic acid (weight part)
(C) N-N methylene base bisacrylamide 1.8 * 10
-3Part (weight part)
(D) 0.5 part of ammonium persulphate (weight part)
(E) 350 parts in water (weight part)
The purposes of 5. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises:
(A) 150 parts of acrylamides (weight part)
(B) 15 parts of anhydrous sodium carbonates (weight part)
(C) N-N methylene base bisacrylamide 1.5 * 10
-3Part (weight part)
(D) 0.5 part of Potassium Persulphate (weight part)
(E) 350 parts in water (weight part)
The purposes of 6. 1 kinds of microgel particles of embodiment, the preparation raw material of this microgel particle comprises:
(A) 50 parts of acrylamides (weight part)
(B) 5 parts of anhydrous sodium carbonates (weight part)
(C) N-N methylene base bisacrylamide 1.5 * 10
-5Part (weight part)
(D) 0.15 part of Potassium Persulphate (weight part)
(E) 450 parts in water (weight part)
Component described in the embodiment 3～6 is passed through stirring and dissolving respectively, and logical nitrogen 15 minutes is heated to 70 ℃, and gel is made in the reaction of generation polymerization crosslinking, and pulverize the oven dry back, sieves, and can obtain the microgel particle of adjustable grain.
This microgel particle particle diameter is 0.1～30000 micron, and expansion multiple is 30～200 times, 20～150 ℃ of Applicable temperature scopes, and stability is more than 1 year.
This microgel particle is met water section or is all expanded, and forms to have certain viscoelastic microgel particle.The expansion multiple of gel particle can reach 30～200 times, and diameter can be controlled according to the oil field needs; Density approaches water, exists with the disperse particles that suspends in water, can it be isolated rice from water by filtration or other simple ways; Temperature tolerance is good, and The laboratory results shows that this microgel particle can reach more than 1 year 120 ℃ of conditions following stationary phase; Have salt tolerance preferably, the saltiness height, final expansion multiple is little, and speed of expansion is slow, and the salt solution of 200,000 mg/L still can make this grain expansion more than 30 times, and thermostability is not subjected to the influence of salts contg.
Claims (6)
1. the purposes of a microgel particle, the preparation raw material of this microgel particle comprises: (A) (B) (C) N-N methylene base bisacrylamide 5.0 * 10 of thiazolinyl unsaturated carboxylic acid 6～50 parts (weight part) of thiazolinyl unsaturated amides 40～150 parts (weight part)
-5～5.0 * 10
-3Part (weight part) is 300～450 parts in water of persulfate initiator amount (E) (weight part) (D)
Said components is through stirring and dissolving, and gel is made in the reaction of generation polymerization crosslinking, and pulverize the oven dry back, sieves, and promptly obtains the microgel particle of adjustable grain;
This microgel particle is used for the water injection well profile adjustment and oil displacement.
2. the purposes of microgel particle according to claim 1, the thiazolinyl unsaturated amides is an acrylamide in the preparation raw material of microgel particle, the thiazolinyl unsaturated carboxylic acid is a vinylformic acid, persulphate is an ammonium persulphate, comprising: (A) (B) (C) N-N methylene base bisacrylamide 1.8 * 10 of vinylformic acid 30 parts (weight part) of acrylamide 150 parts (weight part)
-3Part (weight part) be (E) 320 parts in water (weight part) of ammonium persulphate 0.5 part (weight part) (D)
3. the purposes of a microgel particle, the preparation raw material of this microgel particle comprises: (A) (B) N-N methylene base bisacrylamide 5.0 * 10 of thiazolinyl unsaturated amides 50～150 parts (weight part)
-5～5.0 * 10
-3Part (weight part) is 350～450 parts in water of persulfate initiator amount (D) (weight part) (C)
Said components is through stirring and dissolving, and gel is made in the reaction of generation polymerization crosslinking, and pulverize the oven dry back, sieves, and promptly obtains the microgel particle of adjustable grain;
This microgel particle is used for the water injection well profile adjustment and oil displacement.
4. the purposes of microgel particle according to claim 3, the thiazolinyl unsaturated amides is an acrylamide in the preparation raw material of microgel particle, the thiazolinyl unsaturated carboxylic acid is a vinylformic acid, persulphate is a Potassium Persulphate, comprising: (A) (B) (C) N-N methylene base bisacrylamide 1.5 * 10 of anhydrous sodium carbonate 15 parts (weight part) of acrylamide 150 parts (weight part)
-3Part (weight part) be (E) 350 parts in water (weight part) of Potassium Persulphate 0.5 part (weight part) (D)
5. according to the purposes of the described microgel particle of one of claim 1 to 4, it is characterized in that water carries microgel particle and injected by water injection well.
6. according to the purposes of the described microgel particle of one of claim 1 to 4, it is characterized in that, carry microgel particle with oil and inject by recovery well.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98120664 CN1251856A (en) | 1998-10-21 | 1998-10-21 | Usage of gel particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98120664 CN1251856A (en) | 1998-10-21 | 1998-10-21 | Usage of gel particles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1251856A true CN1251856A (en) | 2000-05-03 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 98120664 Pending CN1251856A (en) | 1998-10-21 | 1998-10-21 | Usage of gel particles |
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|---|---|
| CN (1) | CN1251856A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1333036C (en) * | 2003-06-06 | 2007-08-22 | 吴凤祥 | Pre-crosslinked granular plugging agent and its production |
| CN102127410A (en) * | 2010-12-16 | 2011-07-20 | 李水伯 | Slow-swelling pre-crosslinked gel volume expansion grains and preparation method thereof |
| CN102587876A (en) * | 2012-02-24 | 2012-07-18 | 中国石油天然气股份有限公司 | Method for improving oil field recovery ratio by using blasting type pre-crosslinking gel particles |
| CN103541702A (en) * | 2012-07-12 | 2014-01-29 | 中国石油天然气股份有限公司 | Method for improving crude oil recovery ratio of low-permeability sandstone oil reservoir |
| CN104046343A (en) * | 2013-03-12 | 2014-09-17 | 中国石油化工股份有限公司 | High temperature resistant pre-crosslinked granular profile control agent and preparation method and application thereof |
| CN115403699A (en) * | 2021-05-28 | 2022-11-29 | 大庆油田有限责任公司 | Gel particle for oil displacement and preparation method thereof |
| CN115926764A (en) * | 2023-03-13 | 2023-04-07 | 山东科兴化工有限责任公司 | Microgel suspending agent for water injection well and preparation method thereof |
| US11673378B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier thermoformed plastic bottle |
| US11673377B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier packaging film |
| US11673309B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier packaging film |
-
1998
- 1998-10-21 CN CN 98120664 patent/CN1251856A/en active Pending
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1333036C (en) * | 2003-06-06 | 2007-08-22 | 吴凤祥 | Pre-crosslinked granular plugging agent and its production |
| CN102127410A (en) * | 2010-12-16 | 2011-07-20 | 李水伯 | Slow-swelling pre-crosslinked gel volume expansion grains and preparation method thereof |
| CN102587876B (en) * | 2012-02-24 | 2014-11-05 | 中国石油天然气股份有限公司 | Method for improving oil field recovery ratio by using blasting type pre-crosslinking gel particles |
| CN102587876A (en) * | 2012-02-24 | 2012-07-18 | 中国石油天然气股份有限公司 | Method for improving oil field recovery ratio by using blasting type pre-crosslinking gel particles |
| CN103541702B (en) * | 2012-07-12 | 2016-06-08 | 中国石油天然气股份有限公司 | Method for improving crude oil recovery ratio of low-permeability sandstone oil reservoir |
| CN103541702A (en) * | 2012-07-12 | 2014-01-29 | 中国石油天然气股份有限公司 | Method for improving crude oil recovery ratio of low-permeability sandstone oil reservoir |
| CN104046343A (en) * | 2013-03-12 | 2014-09-17 | 中国石油化工股份有限公司 | High temperature resistant pre-crosslinked granular profile control agent and preparation method and application thereof |
| CN104046343B (en) * | 2013-03-12 | 2017-02-08 | 中国石油化工股份有限公司 | High temperature resistant pre-crosslinked granular profile control agent and preparation method and application thereof |
| US11673378B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier thermoformed plastic bottle |
| US11673377B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier packaging film |
| US11673309B2 (en) | 2020-11-23 | 2023-06-13 | Henry G. Schirmer | Crystal clear high barrier packaging film |
| CN115403699A (en) * | 2021-05-28 | 2022-11-29 | 大庆油田有限责任公司 | Gel particle for oil displacement and preparation method thereof |
| CN115403699B (en) * | 2021-05-28 | 2024-01-30 | 大庆油田有限责任公司 | Gel particle for oil displacement and preparation method thereof |
| CN115926764A (en) * | 2023-03-13 | 2023-04-07 | 山东科兴化工有限责任公司 | Microgel suspending agent for water injection well and preparation method thereof |
| CN115926764B (en) * | 2023-03-13 | 2023-05-05 | 山东科兴化工有限责任公司 | Microgel suspending agent for water injection well and preparation method thereof |
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