Method of selectively inhibiting gelation of hydrophobically associating substances

FIELD: polymer materials.

SUBSTANCE: invention, in particular, relates to hydrophobically modified water-soluble polymers or complexes of the latter with surfactants and discloses a method for selectively inhibiting gelation of hydrophobically associating gel-forming liquid containing hydrophobically associating water-soluble polymers or complexes of the latter with surfactants. Advantage of invention resides in that, when thus inhibited liquid contacts with a hydrocarbon medium, inhibitory effect is preserved and gelation does not occur and, when liquid contacts with an aqueous medium, inhibitory effect is cancelled and gelation takes place. Inhibitor is selected such that it is well soluble in aqueous media but insoluble in hydrocarbon media, for example ethanol or methanol. Hydrophobically associating substance in associating gel-forming liquid is, in particular, hydrophobically modified water-soluble polymer based on polyacrylamide containing 84.4 or 88.8 mol % acrylamide units, 1.5 mol % n-dodecylacrylamide units, and 14.1 or 9.7 mol % sodium acrylate units. Surfactant used in polymer complexes is, in particular, cetylpyridinium chloride. Invention further discloses associating gel-forming liquid containing 1 to 10% by weight of hydrophobically associating substances and also composition for treating oil well, which comprises associating liquid. Disclosed is also a method for selectively blocking water entry into producing oil well from underground water-bearing formations. Invention can thus be used in oil production to control water inflows in oil-production well allowing restriction of water entry into well without unfavorably affecting oil production process.

EFFECT: facilitated gelation control in polymer-containing liquids.

4 cl, 2 dwg, 1 tbl

 

The technical FIELD

The present invention relates to a method of selective inhibition of gelation associating gel-forming liquid containing a hydrophobic associating substances. The invention relates also to associate the gel-forming liquid capable of selective gelation depending on the type of medium (water or hydrocarbon), in contact with which it is situated. The invention can be applied in the oil industry for the limitation of the water in the producing oil well, and keep a steady flow of oil.

Prior art

All oil wells along with the oil is extracted and the water flowing into the well. As aging wells the amount of produced water increases. From depleted oil reservoirs is pumped at an average of about 3 tons of water per 1 ton of crude oil [1]. The use of modern methods of limitation of the water can significantly reduce the costs of oil production and, more importantly, to provide the most complete recovery of oil from the subsoil. A promising method for limitation of the water is the use of selective liquids, able to selectively lock the water flow without disturbing the flow of oil [2]. This requires the injection into the borehole selective liquid had a low viscosity, what about later over time formed the gel ("tube") in those zones of the well, where there is water flow. At the same time in contact with the oil gelation will not occur.

The main component of selective liquid is hydrophobic associating substance (AB), capable of forming a physical gel in the aquatic environment [2, 3]. Such substances include, in particular, hydrophobic modified polymers, viscoelastic surfactants (surfactant) and their complexes [2, 3].

The formation of physical gels of hydrophobically modified polymers described in many works, for example [4-6]. The formation of physical gels of viscoelastic surfactants described in [7-9]. Gelation in the complexes of the polymer/surfactant described in [10-12].

The disadvantage of these hydrophobic associating substances when used in the composition of the selective fluid is that these substances form physical gels almost immediately after placing in the water. Such selective fluid, which is already partially occurred the formation of a physical gel, difficult to inject into the well because of their high viscosity. Another disadvantage of such systems is that the contact is swollen in water physical gel with hydrocarbons often does not lead to the destruction of already formed gel, so that the blockage can be exposed and oil-bearing strata. This is especially true of gels formed hydrophobic modi is these polymers. To overcome these disadvantages it is necessary to solve two problems: (1) to slow down the process of gelation in aqueous medium so that when the injection solution was a low viscosity and a gel was formed in the well under the selective contact of the liquid with water, (2) completely suppress gelation upon contact selective fluid with oil.

For selective fluid containing a viscoelastic surfactant, proposed several ways to slow gelation [3]. At the same time, to the authors ' knowledge this application, a means of monitoring the rate of formation of physical gels in selective fluid containing hydrophobic modified polymers have not been developed yet.

As shown in [13-15], hydrophobic aggregates formed in dilute solutions of hydrophobically modified polymers and complexes of polymer/surfactant can be dissolved in aqueous-organic media. For example, in [13, 14] it is shown that in dilute solutions of hydrophobically modified polyacrylamide hydrophobic aggregates are destroyed when added to water 20-50 vol.% acetonitrile. This solvent is used to determine the molecular weight of individual macromolecules by the GPC method. Similar behavior is observed in the complexes of the polymer/surfactant. In [15] it is shown that in mixtures of water/ethanol and water/isopropanol, the content is asih 40-50 vol.% alcohol, is the destruction of the complexes of the polymer/surfactant due to the weakening of hydrophobic interactions. However, in the above work says nothing about the influence of organic solvents on the formation of physical gels.

As was established by the authors, a similar approach can be successfully used for monitoring formation of physical gels in selective polymer-containing fluids, providing (1) a slowdown in the process of gelation in aqueous medium and (2) complete suppression of gelation upon contact with hydrocarbons, which allowed us to make the present invention.

The INVENTION

In accordance with the present izobretenii proposes a method of selective inhibition of gelation associating gel-forming liquid containing a hydrophobic associating substance representing hydrophobically modified water-soluble polymers or complexes of such polymers with surfactants, which provides in case of contact associating fluid with a hydrocarbon environment preservation inhibitory effect, so that gelation does not occur, and in case of contact associating fluid with the aqueous environment, the disappearance of the inhibitory effect, so that gelation occurs, consisting in the fact that in these liquid before bringing them into pins these environments impose inhibitor, the inhibitory hydrophobic Association hydrophobic associating substances, which is well soluble in water, but insoluble in hydrocarbon environments.

In the invention serves also capable of selective gelation of the associative gelling liquid containing 1-10 wt%. hydrophobic associating substances representing a hydrophobically modified water-soluble polymers or complexes of these polymers with surfactants, the gelation inhibitor effective to prevent gelation of the number and the aquatic environment, with the specified inhibitor is an inhibitor that suppresses hydrophobic Association hydrophobic associating substances and which is well soluble in water and practically insoluble in hydrocarbon environments.

Further, in the invention features a composition for treatment of oil wells, including such associated fluid capable of selective gelation, which contains hydrophobic associating substance representing hydrophobically modified water-soluble polymers or complexes of these polymers with surfactants, the gelation inhibitor effective to prevent gelation of the number and the aquatic environment, and the specified inhibitor is an inhibitor that suppresses hydrophobic Association is hydrophobic associating substances and which is well soluble in water and practically insoluble in hydrocarbon environments.

In the present invention it is also proposed a method of selective blocking the flow of water in mining oil well from an underground aquifer in which the well bore pump of the above compound for the treatment of oil wells, comprising associating fluid that forms over time, blocking gel tube only in those places well, where associating the liquid is in contact with an aqueous medium, and does not form tubes in contact associating fluids with oil.

BRIEF DESCRIPTION of FIGURES

Figure 1 shows the frequency dependence of the components of the complex modulus of elasticity of the polymer solution of example 1, which was in contact with an aqueous medium.

Figure 2 shows the frequency dependence of the components of the complex modulus of elasticity of the polymer solution of example 1, were in contact with the hydrocarbon.

DETAILED description of the INVENTION

In the present invention proposes a composition is associative gelling fluid and method of selective inhibition of gelation associative gelling fluid, allowing you to control the rate of formation of a physical gel. Thus control the rate of formation of a physical gel is carried out in such a way as to make the process of selective gelation, that is, the head is reported from in contact with any medium (water or hydrocarbon) is the solution of associating substances.

This goal is achieved due to the fact that the associative gelling liquid add the gelation inhibitor, which, firstly, it suppresses hydrophobic Association hydrophobic associating substances and, secondly, is a substance, soluble in water, but insoluble in hydrocarbons. Therefore, when the contact associated gelling liquid water inhibitor is transferred from the volume associated gelling liquid in water, and its concentration in associating fluid is reduced, which causes gelation of the liquid that has previously been suppressed by the inhibitor. On the other hand, when the contact associated gelling liquid hydrocarbons, in which the insoluble inhibitor, gelation does not occur, since the inhibitor remains in the amount of associative gelling liquid and continues to suppress gelation.

In the present invention are also compound for the treatment of oil wells on the basis of the above associating fluid and process for the selective blocking of the flow of water in mining for oil from underground aquifers using such a composition.

As selective inhibitors of gelation at present is eating the invention can be used solvents, which as inhibitors is to suppress hydrophobic Association responsible for gelation, and which are mixed with water, but not mixed with hydrocarbons, such as methanol, ethanol, acetonitrile, etc.

The physical gel formed in the aquatic environment, had a rather high mechanical characteristics, as polymers, use of hydrophobic modified polymers containing a sufficient number of associating groups with strong hydrophobic properties, is able to provide strong binding of the polymer chains between themselves due to the formation of hydrophobic complexes, or complexes such hydrophobically associating polymers with surfactants. One of the possible types of hydrophobically modified polymers based on polyacrylamide represented by the following formula:

where R=-(CH2)nCH3, n=8, 11; X=-O-NH; Y=-H, -CH3.

The proposed composition is associative gelling fluid and method of selective inhibition of gelation associating gel-forming liquid can be used to selectively block the flow of water in mining for oil from underground aquifers, and keep a steady flow of oil. The inhibitors included in an associate the ith fluid, used for the selective blocking of the flow of water in mining oil well, allow to suppress hydrophobic Association responsible for gelation. Therefore, the viscosity of the composition prior to its injection into the well is negligible. At the same time, the presence of these inhibitors in associating fluid improves wetting conditions at its contact with the rock, which promotes a more efficient penetration selective fluid to the "job site" extractive oil wells after the injection in this well. Over time pumped into the borehole associating fluid according to the invention forms a blocking gel tube in those places well, where the liquid is in contact with the aqueous medium. In places of contact of associating fluids with oil gelation continues to be suppressed by the inhibitor, and the gel plugs are not formed.

The invention further additionally illustrated by the following not limiting examples.

Example 1.

0.2 g of terpolymer I containing 84,4 mol.% acrylamide, a 1.5 mol.% n-dodecylamine and 14.1 mol.% sodium acrylate synthesized by the method of micellar polymerization at a concentration of sodium dodecyl sulphate to 1.5 wt.% and the total concentration of monomers 3.0 wt.%, dissolved in 10 ml of a mixture of ethanol (60%) and water (40%vol.) when continuous lane is mesheanii within 2 hours. To simulate the contact of the polymer solution with reservoir water, 1 ml of the prepared polymer solution is poured to 20 ml of an aqueous salt solution containing 30 g/l of sodium chloride and 3 g/l of calcium chloride. To simulate contact with oil, 1 ml of the polymer solution is poured 20 ml of n-heptane. After 2 weeks measure the frequency dependence of the complex modulus of elasticity of the polymer solutions were in contact with aqueous salt solution and n-heptane. They are presented in figure 1 and 2. It is seen that in the sample who were in contact with water, in the frequency range from 0.01 to 10 Hz modulus of elasticity higher than the loss modulus, i.e. the sample is a physical gel. At the same time in the sample who were in contact with n-heptane, in the frequency range from 0.1 to 10 Hz modulus of elasticity lower than the loss modulus, i.e. in this sample, gelation did not occur. Values of modulus of elasticity, measured at a frequency of 0.1 Hz, and the initial viscosity of the polymer solution shown in table 1.

Example 2.

to 0.060 g terpolymer I (composition described in Example 1) are dissolved in 3.8 ml of a mixture of methyl alcohol (53%) and water (47%). Examine the change in rheological properties of the solution upon contact with the aqueous salt solution and n-heptane as described in Example 1. Measurement data are shown in table 1.

Example 3.

0.3 g terpolymer II, containing an 8.8 mol.% acrylamide, a 1.5 mol.% n-dodecylamine and 9.7 mol.% sodium acrylate synthesized by the method of micellar polymerization at a concentration of sodium dodecyl sulfate 3.0 wt.% and the total concentration of monomers 3 wt.%, dissolved in 10 ml of a mixture of ethanol (40%vol.) and water (60 vol.%) under continuous stirring for 2 hours. Examine the change in rheological properties of the solution upon contact with the aqueous salt solution and n-heptane as described in Example 1. Measurement data are shown in table 1.

Example 4.

The gel-forming mixture on the basis of terpolymer I prepared as described in Example 1, except that 4 ml of a mixture of optionally poured 70 μl of an aqueous solution of surfactant - cetylpyridinium chloride concentration at 0.020 mol/l Examine the change in rheological properties of the solution upon contact with the aqueous salt solution and n-heptane as described in Example 1. Measurement data are shown in table 1.

tr>
Table 1.

Comparison of moduli of elasticity of the samples selective fluid after contact with the aqueous medium with n-heptane.
ExampleThe viscosity of the initial solution, the PA·G' of the sample at a frequency of 0.1 Hz, PA
Contact with an aqueous mediumContact with n-heptane
10.13670.16
20.525.30.36
30.33230.47
40.1812.00.85

Thus, similar results (formation of a physical gel upon contact with water and the absence of gelation upon contact with n-heptane) were obtained for a variety of hydrophobically modified polymers and complexes with hydrophobic modified polymer/surfactant in the presence of various inhibitors.

Literature.

1. Bailey, B., Crabtree M, tire D., Kucuk, F., Romano, K., Rudhart L., elfic D. Diagnosis and limiting water production. "Oil and gas review, spring 2001, p.44.

2. Patent WO 99/49183 on September 30, 1999

3. US patent # US 6194356 B1 from February 27, 2001

4. Bock J., Valint P.L., Jr., Pace S.J., Siano D.B., Schuiz D.N., Turner S.R. Hydrophobically associating polymers. In Water-Soluble Polymers for Petroleum Recovery; G.A. Stahl, Schuiz D.N., Eds.; Plenum Press: New York, 1988; pp.147-160.

5. Regalado E.J., Selb J., Candau F. Viscoelastic behavior of semidilute solutions of multisticker polymer chains. Macromolecules 1999, v.32, pp.8580-8588.

6. Chassenieux S., J. Fundin, G. Ducouret, Iliopoulos I. Amphiphilic copolymers of styrene with a surfactant-like comonomer: gel formation in aqueous solution. J. Molecular Structure 2000, v.554, pp.99-108.

7. Rehage, H., Hoffmann H. Viscoelastic surfactant solutions: model systems for rheological research. Mol. Phys. 1991, v.74, pp.933-973.

8. Hoffmann H. In Structure and Flow in Surfactant Solutions; ACS Symp. Ser 578; Herb C.A., R. Prudhomme, Eds. American Chemical Society: Washington, DC, 1994; pp.2-31.

9. S.R. Raghavan, E.W. Kaler Highly viscoelastic wormlike micellar solutions formed by cationic surfactants with long unsaturated tails. Langmuir 2001, v.17, pp.300-306.

10. Iliopoulos I., Wang AS, Audebert R. Viscometric evidence of interactions between hydrophobically modified poly(sodium acrylate) and sodium dodecyl sulfate. Langmuir 1991, v.7, pp.617-620.

11. Sarrazin-Cartalas A., Iliopoulos I., Audebert R., Olsson U. Association and thermal gelation in mixtures of hydrophobically modified polyelectrolytes and non-ionic surfactants. Langmuir 1994, 10, pp.1421-1426.

12. Piculell L., Thuresson K., O. Ericsson Surfactant binding and micellisation in polymer solutions and gels: binding isotherms and their consequences. Faraday Discussions 1995, v.101, pp.307-318.

13. Noda T., Morishima Y. considered are hydrophobic association of random copolymers of sodium 2-(acrylamido)-2-methylpropanesulfonate and dodecyl methacrylate in water as studied by fluorescence and dynamic light scattering. Macromolecules 1999, v.32, pp.4631-4640.

14. I.V. Blagodatskikh, Sutkevich M.V., Sitnikova N.L., Churochkina N.A., Pryakhina T.A., Philippova O.E., Khokhlov A.R. Polymers with strongly interacting groups. Molecular weight characterization using GPC/LS. J. Chromatography, in press.

15. Khandurina J.V., Rogachev V.B. have been, Zezin A.V., V.A. Kabanov Stability of polycomplexes net polyelectrolyte-surfactant in water-salt and water-organic media. Polymer sciense ser. Conn. 1994, T.36, No. 2, s-246.

1. The method of selective inhibition of gelation associating gel-forming liquid containing a hydrophobic associating substance representing hydrophobically modified water-soluble polymers or complexes of these polymers with surfactants, ensuring in case of contact associiruyuschihsya with a hydrocarbon environment preservation inhibitory effect so that gelation does not occur, and in case of contact associating fluid with the aqueous environment, the disappearance of the inhibitory effect, so that gelation occurs, characterized in that the said liquid before bringing them into contact with these environments impose inhibitor that suppresses hydrophobic Association hydrophobic associating substances, which is well soluble in water, but insoluble in hydrocarbon environments.

2. The method according to claim 1, where the hydrophobic associating substances associated gelling liquid contains hydrophobically modified water-soluble polymer on the basis of polyacrylamide containing 84,4 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 14.1 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulphate to 1.5 wt.% and the total concentration of monomers 3.0 wt.%.

3. The method according to claim 2, wherein the associating fluid optionally add a surfactant solution of cetylpyridinium chloride at the rate of 70 μl of the surfactant solution concentration of 0.02 Mol/l to 4 ml of associating fluids.

4. The method according to claim 1, where the hydrophobic associating substances associated gelling liquid contains hydrophobically modified water-soluble polymer based on polyacrylamide, containing the s and 88.8 mol.% acrylamide links, a 1.5 mol.% n-dodecylamine links and 9.7 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulfate 3.0 wt.% and the total concentration of monomers 3.0 wt.%.

5. The method according to any one of claims 1 to 4, where the inhibitor use ethanol.

6. The method according to any one of claims 1 to 4, where the inhibitor use methanol.

7. Associating the gel-forming liquid containing 1-10 wt.% hydrophobic associating substances representing a hydrophobically modified water-soluble polymers or complexes of these polymers with surfactants, the gelation inhibitor effective to prevent gelation of the number and the aquatic environment, characterized in that the inhibitor is an inhibitor that suppresses hydrophobic Association hydrophobic associating substances and which is well soluble in water and practically insoluble in hydrocarbon environments.

8. Associating the gel-forming liquid according to claim 7, where the hydrophobic associating substance use hydrophobic modified water-soluble polymer on the basis of polyacrylamide containing 84,4 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 14.1 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of dodecylsulfate the sodium of 1.5 wt.% and the total concentration of monomers 3.0 wt.%.

9. Associating the gel-forming liquid of claim 8, characterized in that it further contains a surfactant, pyridinium chloride at the rate of 70 μl of the surfactant solution concentration of 0.02 Mol/l to 4 ml of associating fluids.

10. Associating the gel-forming liquid according to claim 7, where the hydrophobic associating substance use hydrophobic modified water-soluble polymer on the basis of polyacrylamide containing 88,8 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 9.7 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulfate 3.0 wt.% and the total concentration of monomers 3.0 wt.%.

11. Associating the gel-forming liquid according to any one of claims 7-10, where the inhibitor use ethanol.

12. Associating the gel-forming liquid according to any one of claims 7-10, where the inhibitor use methanol.

13. Compound for the treatment of oil wells, comprising associating a liquid containing a hydrophobic associating substances, which are hydrophobically modified water-soluble polymers or complexes of these polymers with surfactants, the gelation inhibitor effective to prevent gelation of the number and the aquatic environment, characterized in that the inhibitor is an inhibitor that pod is the focus of hydrophobic Association hydrophobic associating substances and which is well soluble in water and practically insoluble in hydrocarbon environments.

14. The composition according to item 13, where the hydrophobic associating substance use hydrophobic modified water-soluble polymer on the basis of polyacrylamide containing 84,4 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 14.1 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulphate to 1.5 wt.% and the total concentration of monomers 3.0 wt.%.

15. The composition according to 14, characterized in that the associative gelling liquid further comprises a surfactant, pyridinium chloride at the rate of 70 μl of the surfactant solution concentration of 0.02 Mol/l to 4 ml of associating fluids.

16. The composition according to item 13, where the hydrophobic associating substance use hydrophobic modified water-soluble polymer on the basis of polyacrylamide containing 88,8 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 9.7 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulfate 3.0 wt.% and the total concentration of monomers 3.0 wt.%.

17. The composition according to any one of p-16, where the inhibitor use ethanol.

18. The composition according to any one of p-16, where the inhibitor use methanol.

19. Process for the selective blocking of the flow of water in mining oil well from an underground aquifer the seams, including the injection wellbore, comprising associating fluid, forming with time blocking gel tube only in those places well, where associating the liquid is in contact with an aqueous medium, and not forming plugs in the contact associated with the liquid oil, characterized in that, as mentioned composition for treatment of an oil well using the composition according to item 13.

20. The method according to claim 19, where the hydrophobic associating substances associated fluid contains hydrophobically modified water-soluble polymer on the basis of polyacrylamide containing 84,4 mol.% acrylamide links of 1.5 mol.% n-dodecylamine links and 14.1 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulphate to 1.5 wt.% and the total concentration of monomers 3.0 wt.%.

21. The method according to claim 20, wherein the associating fluid optionally add a surfactant solution of cetylpyridinium chloride at the rate of 70 μl of the surfactant solution concentration of 0.02 Mol/l to 4 ml of associating fluids.

22. The method according to claim 19, where the hydrophobic associating substances associated fluid contains hydrophobically modified water-soluble polymer on the basis of polyacrylamide containing 88,8 mol.% acrylamide links of 1.5 mol.% n-dodecyltin midnig links and 9.7 mol.% parts of sodium acrylate, obtained by the method of micellar polymerization at a concentration of sodium dodecyl sulfate 3.0 wt.% and the total concentration of monomers 3.0 wt.%.

23. The method according to any of PP-22, where the inhibitor use ethanol.

24. The method according to any of PP-22, where the inhibitor use methanol.



 

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EFFECT: provision of vibratory and wave well bottom zone treatment within wide frequency range.

1 dwg

FIELD: methods or apparatus for obtaining oil, gas, water from wells, particularly to produce methane from multizone oil reservoir and for reservoir development by underground leaching method.

SUBSTANCE: system comprises production and auxiliary wells with production, filtering and extraction or injection strings. Area of productive wells provided with filtering strings is divided into upper and lower isolated zones. Upper zones of production wells are auxiliary zones, upper zones of auxiliary wells are production ones. Production zones communicates one with another, auxiliary ones are isolated from productive well columns and are communicated with extraction or injection strings.

EFFECT: increased efficiency of product development and reduced capital outlays.

4 cl, 1 dwg

FIELD: oil production industry, particularly for well operation in complicated environment.

SUBSTANCE: plant includes main cased well bore, additional well bore provided with extension pipe and pump. In accordance with the first embodiment main well bore is drilled up to reaching roof of upper clay rock interval. Extension pipe is arranged in additional bore of oil production well, spaced therefrom and is not subjected to cementation. Extension pipe is provided with packing devices located above roof of each clay rock interval penetrated by additional bore of oil production well. Extension pipe is perforated below bottom of each clay rock interval and provides clay rock interval flooding with oil during production well operation. In another embodiment main oil production well bore is drilled up to reaching roof of upper clay rock interval. Extension pipe is arranged in additional bore of oil production well, spaced therefrom and is not subjected to cementation. The extension pipe is connected with pump. Lower end of the extension pipe extends below clay rock interval and provides flooding of above interval with oil during oil production well operation.

EFFECT: increased oil production output and reliability of clay rock interval isolation from water.

2 cl, 2 dwg

FIELD: oil production industry, particularly gas and/or oil producing wells, especially to increase hydrocarbon output from thick nonuniform productive reservoir through created filtering system.

SUBSTANCE: method involves cutting opening in casing pipe of the well within productive reservoir capping interval; additionally penetrating in separate productive reservoirs and/or beds and/or lenticels of the reservoir through previously cut opening and side channels; placing filtering material in the side channels and main well bore under pressure of natural vertical productive reservoir cracks opening and securing above cracks in opened state to activate fluid filtering of productive reservoir into producing well, wherein filtering material pressure in peripheral side channels spaced maximal distance from main well bore exceeds pressure of natural vertical productive reservoir cracks opening.

EFFECT: increased well yield and overhaul period, improved efficiency due to increased open area of the filtering system in proximal productive reservoir zone adjoining producing well and reduced costs and time for filtering system creation due multidirectional natural cracks utilization.

8 cl

FIELD: oil and gas industry, particularly means to provide optimal filtration mode in wells characterized by sand sloughing in the product.

SUBSTANCE: method involves extracting product of filterless well through perforated area and controlling sand content in product when well production rate declines. When sand particles with angular shape appear in the product during designed recovery of well production rate by increasing depression drawdown inside well secondary well perforation is carried out in zone containing no clay interlayers. The secondary well perforation is performed with shot density of not less than 70% of the primary one and with channel cross-section 1.15 - 5 times greater than that of the primary one. Perforation channel length is 15% greater than range of stress in active filtration zone of productive bed rock under maximal pressure drop.

EFFECT: increased efficiency due to method simplicity, reduced time and material consumption along with maintaining operational characteristics and well operational safety.

5 cl

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes placing alkali waste from kaprolaktam or its solutions production into well as working liquid, in volume not less than volume of pores and/or cracks of productive bed in radius of mudding area from well shaft. Working liquid is pressed into productive bed in saturation mode for this bed along whole thickness thereof. For this saturation of productive bed is performed at pressure of opening of its natural cracks and in cyclic mode of pressure increase, its exposure and pressure drop. This is realized for pressure gradient during loading of productive bed to be 1.1-1.8 times less than pressure gradient during unloading of productive bed.

EFFECT: higher efficiency.

6 cl

The invention relates to the oil industry, in particular to ensure reliable filtration communication between the reservoir and wellbore during its operation, and may find application also in the primary opening of the reservoir, the secondary opening of the reservoir, or temporarily killing the well for a limited time
The invention relates to the field of the oil industry and can find application in various impacts on the reservoir during operation of the well and, in particular, with its perforations, killing for the possibility of repair of wells, emergency shutdown, the intensification of oil production, the alignment of the injectivity profile while maintaining reservoir pressure, for example, flooding, etc

The invention relates to the oil industry, in particular to a method of regulating the permeability of heterogeneous reservoirs using chemical reagents
The invention relates to technology for downhole hydrocarbon production and focus on improving the injectivity of injection wells used for reservoir pressure maintenance in producing wells
The invention relates to the oil and gas industry and can find application in various technological operations in wells and, in particular, when the perforation of the well, the isolation neftegazovodoproyavleny, its killing etc

FIELD: oil and gas production.

SUBSTANCE: invention is designed for use when blocking absorbent formations and killing wells during hole pull-out completion. Composition of invention contains 4.5-50.2. hydrocarbon phase, 1.8-78.5% waste derived from sunflower oil refinement or its phosphatide concentrate, and water phase - the balance.

EFFECT: prevented pollution of productive part of formation with killing fluid, improved blocking properties of composition, and extended resource of vegetal-origin raw materials.

1 tbl, 10 ex

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