Oil recovery composition

FIELD: oil and gas production.

SUBSTANCE: invention is intended for use during development of oil pools at different waterflooding phase for intensifying functioning of producing wells and increasing current oil recovery of formation. Composition contains, wt %: liquid hydrocarbon 10.0-20.0, oil-soluble surfactant 0.3-5.0, water-soluble or water-oil-soluble surfactant 0.1-1.0, superfine hydrophobic material 0.1-2.0, and water (the rest). Composition may further contain 0.3-5.0% calcium chloride. Oil recovery is increased owing to hydrophobization of formation structure, reduction of surface tension in water/rock/oil phase boundary, increase in detergent power of polluted surface, increase in composition viscosity, and increase of relative permeability of the formation for hydrocarbon phase as compared with water phase.

EFFECT: increased oil recovery.

2 cl, 2 tbl, 2 ex

 

The invention relates to the extraction of oil from the reservoir, in particular compositions for oil recovery, and can be used in the development of oil fields in any stage of flooding, to intensify the work of producing wells, increasing the current oil recovery.

Famous oil-driving micellar mixture containing hydrocarbon 10-70 wt.%; surfactant 6-14 wt.%; alcohol is 0.8 to 6.0 wt.% and water 10-80 wt.% (patent SU 1473721, E 21 In 43/22, publ. 15.04.89., Bull. No. 14).

Specified oil-driving blend has good oil-driving properties, but has a high consumption of surfactants and metastability composition.

Known composition to extract oil containing neonol AF9-4 2.0 to 4.0 wt.%, anionic water-soluble surfactants of 6.0 to 12.0 wt.%; liquid hydrocarbon is 10.8-30.0 wt.% and water 52,0-to 77.7 wt.% (..SU No. 1668642, E 21 In 43/22, publ. 07.08.91, bull. No. 29).

This composition, having a high oil-driving properties, has a high consumption of surfactants, especially anionic surfactants, as at the meeting of the composition in the reservoir with saline water more than 17 g/l may salting out of natural latex, which leads to disruption of the stability of the composition.

Known invert microemulsion for processing oil reservoirs containing 10.0 to 20.0 wt.% liquid hydrocarbon, 0.3-5.0 wt.% Netanya NC, 0.3 to 1.5 wt.% calcium chloride and water - the rest (patent No. 2110675,6, E 21 3/22, publ. 10.05.98, bull.№13).

However, a well-known microemulsion insufficient reduces the surface tension at the phase boundary water - rock - oil, has insufficient washing action of the contaminated surface.

The closest in technical essence and the achieved result is a composition for extracting oil containing liquid hydrocarbon 10.0 to 20.0 wt.%, oil-soluble surfactants neprinol NC 0.3 to 3.0 wt.%, water-soluble surfactants NGL-10 (NGL-11) of 0.1 to 1.0 wt.% and water - the rest. (EN 2065033, E 21 B 43/22, 10.08.1996).

As water-soluble surfactants used NGL-10 or NGL-11-water-alcohol solution of alkylsilane sodium, which constitute the liquid from colorless to light brown color, having a density at 20°1,17-1,21 g/cm3and containing ethyl alcohol 12-18 wt.%.

Additive NGL-10 or NGL-11 enhances the hydrophobic properties of the prototype within 8 hours.

The objective of the proposed invention is to increase oil recovery by increasing the hydrophobization of the reservoir rock, decreasing the surface tension at the phase boundary water - rock - oil and increase the cleaning action of the contaminated surface, and increasing the viscosity of the composition and increase the relative permeability of the reservoir for hydrocarbon phase is compared to water.

The task is solved by Thu the proposed composition for extracting oil contains liquid hydrocarbons, the mixture of surfactants and water, characterized in that it contains as a surfactant oil, water or sadomasochistically surfactants and optionally finely dispersed hydrophobic material in the following ratio, wt.%:

Liquid hydrocarbon 10,0-20,0

Oil-soluble surfactant 1,0-5,0

Water-soluble or

sadomasochistic surfactant of 0.1-1.0

Fine

the hydrophobic material of 0.1-2.0

Water the rest

Composition for oil recovery according to claim 1, characterized in that it further contains calcium chloride in the amount of 0.3-5.0 wt.%.

As the liquid hydrocarbon used stable gasoline, hexane fraction (a mixture of saturated hydrocarbons With6-C8and above), gas condensate, gasoline nefras, diesel fuel, and low-viscosity oil and other hydrocarbon solvents.

As oil-soluble surfactant use neprinol NC containing hydrocarbon solution of the esters of the acids of tall oil and triethanolamine;

neonols AF94-6 - nonionic nonylphenols, sciterian 4-6 moles of oxyethylene; and Neftekhim, containing a complex mixture of derivatives of carboxylic acids, lung tall oil and salt piperizine of these acids in the solution of kerosene and catalyzate reforming; oil-soluble petroleum sulfonates with MM=600-00, synthetic alkylarylsulfonate (for example, alkylnaphthalenes), reactant sinol-EM containing hydrocarbon solution of the product of the interaction of the acids of tall oil with triethanolamine and urea, alkylchloride and oxide alkyldiphenylamine and other oil-soluble surface-active substances.

As water-soluble nonionic surfactants are used neonol AF9-12 - Nonylphenol, ethoxylated with 12 moles of ethylene oxide, or a low-melting form SNO-ZB, as water-soluble anionic surfactant-Las or as sadomasochistic surfactant is a mixture of anionic and nonionic surfactants in the composition of the ML-80 ML-81B (winter version) and other water-soluble and sadomasochistically surfactants.

As superfine material used is chemically modified on the surface of highly dispersed materials tetrafluoroethylene, oxides of silicon, titanium, iron, chromium, zinc, aluminum, polyvinyl alcohol, and fine materials of silicon oxides brand Policy.

Fine materials are chemically inert material with an average size of individual particles from 0.1 to 100 μm and a bulk density of 0.1 to 2.0 g/cm3with boundary wetting angles from 114 to 178° and the degree of hydrophobicity from 96,0 do,99%. They do not have harmful effects on humans and the environment.

As Policie use of chemically modified silica (SiO2and depending on the method of modification applied hydrophobic (Policy-P1) and devilry (Policy-DF).

Policy is a trademark of chemically modified silica (SiO2) (Trademark “Policy”, certificate No. 196999 from 06.12.2000 year).

Policy-P1 has a strong hydrophobic and organophilic properties, which means it represents a fine powder on the basis of silicon dioxide, chemically modified organosilicon compound has a bulk density a 0.035-0.14 g/cm3particle size of 0.005 to 0.04 μm, specific surface area 300 m2/g, the effective contact angle for the surface-treated Policrom-P1 140-170°, the range of working temperatures from -60 to +180°With the degree of hydrophobicity -99% (TU 2169-001-0470693-93).

Policy-DF has the properties of a solid nonionic surfactants due to the chemical structure of the grafted surface layer possesses emulsifying properties, has a bulk density a 0.035-0.14 g/cm3particle size of 0.005 to 0.04 μm, specific surface area 300 m2/g, the effective contact angle for the surface-treated Policrom-DF 0°, the range of working temperatures from -60 to +180°With the degree of hydrophobicity of -100% (THE 2311-002-4706-93).

Modified dispersion materials are chemically inert powders that will have no adverse impact on human health and the environment, in accordance with the “Primary Toxicological-hygienic passport new connection”, approved by the RF Ministry of health, this class of materials is according to GOST 12.007-76 to the 4th class of low-hazard substances. Storage conditions of Policie: dry location at temperatures from-50 to +50°C.

Comparative analysis of the prototype allows us to conclude that the proposed composition differs from the known introduction of a new component is highly dispersed hydrophobic material.

In addition, the composition may additionally contain calcium chloride in the amount of 0.3-5.0 wt.%.

After downloading the proposed composition containing finely dispersed hydrophobic material, the increase in oil recovery is achieved by increasing the hydrophobization of the reservoir rock, decreasing the surface tension at the phase boundary water - rock - oil and increase the cleaning action of the contaminated surface, and increasing the viscosity of the composition and increase the relative permeability of the reservoir for hydrocarbon phase is compared to water.

Highly dispersed hydrophobic material of the above modifications, introduced into the composition, having a submicron particles, easily pron is producing the pores and microcracks formation, modifies energy surface (wettability). This qualitatively changes the filtration characteristics of the reservoir for water and for oil.

The proposed composition containing finely dispersed hydrophobic material with a degree of hydrophobicity from 96,0 up to 99.99%, largely hydrofobicity the rock surface. The hydrophobization of the surface of the breed is the result of a consolidation of fine material in the pore volume due to the small size of its particles and due to forces of adhesion, but also due to changes in wetting angle to 170-178° and reduce surface tension.

After downloading the proposed composition, for example, a clay-containing reservoir layer is tobitatsu clay particles, resulting in reduced thickness of the hydration shells surrounding the clay particles, which increases the effective size of the pore channels and reduction of swelling clay particles.

The composition may contain modified material brand Policy-DF. Due to the structure of the grafted surface layer POLYSIL-DF has the properties of a solid nonionic surfactant.

In the result of consolidation in the pore volume due to the small size of its particles and due to forces of adhesion Policy-AF dramatically reduces the surface tension at the border once the eating phase water - rock - oil, increasing permeability of the fluid.

Add material brand Policy-DF in the composition enhances the cleaning effect of the contaminated surfaces and leads to emulsification of the fat and oil pollution, dispersion and stabilization of the particles of solid impurities (ASPO).

Unlike the prototype, where as a component that increase the hydrophobic properties of the composition used aqueous-alcoholic solution NGL-10 (NGL-11), which increases gidrofobiziruyuschey the ability of the composition within 8 hours, included in the modified hydrophobic material of the above modifications due to its high dispersibility is well fixed in the pore space and the disproportionately greater increases gidrofobiziruyuschey ability, because the hydrophobic material has a hydrophobicity 96,0-to 99.99%, for example, highly dispersed hydrophobic material brand POLYSIL-P1 chemical surface modification of silicon dioxide to produce organic silicon compound of General formula Cl4-nSiRnwhere n=1-3; R=H, methyl, ethyl, Cl-methyl, phenyl -, followed by treatment with a compound selected from the group consisting of tetramethoxysilane or tetraethoxysilane, or polymethylsilane.

Use defiling dispersed material POLYSIL-AF significantly reduces surface Natai the tion on the phase boundary water rock - oil and increases the cleaning effect of the emulsion.

The result is the introduction of a modified superfine material of different brands and calcium chloride increases the viscosity, sedimentation stability, hydrophobic and surface active properties of the emulsion and increases the insulating effect of the composition.

By increasing the concentration of highly dispersed hydrophobic material introduced into the composition, increases the stabilizing effect of it, which allows to obtain a stable emulsion of a higher viscosity.

The presence of calcium chloride increases the stability of emulsions with increasing temperature from 20 to 85°C. This affects mainly through chemical transformations of emulsifier in the emulsion and changes in the composition of the adsorption layer. The presence of metal cations (calcium) contributes to the behavior of metabolic reactions of formation of metal Soaps of higher carboxylic acids present in the composition of the emulsifier, which leads to a sharp decrease in interfacial tension, more efficient emulsification, stabilization of the emulsion and increase the structural viscosity of the emulsions.

In addition, oil-soluble and water - or sadomasochistically surfactant contained in the proposed structure, increase its surface-active properties, the injection of such composition in Obvodny is installed oil wells surface of the reservoir rock changes the wettability, namely gidrofobizatsija due to hydrophobic chains of the surfactant. When the joint hydrophobization of the surface rocks of surfactants and modified hydrophobic material improves the adhesion of the composition to the breed, which contributes to better hold it in place. The hydrophobization of the surface of the breed also deletes rychlovarnou formation water of the previously drained or poorly drained intervals and zones of the layer.

The proposed composition containing liquid hydrocarbon, oil - in - water or sadomasochistically surfactants, highly dispersed hydrophobic material and water by increasing the viscosity and the waterproofing composition and increase the relative permeability of the reservoir for hydrocarbon phase compared to water will allow you to use it effectively to increase oil recovery.

The proposed composition is prepared as follows. In the calculated quantity of a solution of oil-soluble surfactants in a liquid hydrocarbon under mechanical stirring enter the estimated amount of the hydrophobic material of the above brands and dispense small amounts calculated amount of water or sadomasochistic surfactant in water or an aqueous solution of calcium chloride, stirred thoroughly until a homogeneous emulsion of the type water-in-oil”.

Example 1. Prepare the emulsion on the proposed composition: 10 ml GE is canovai faction added under mechanical stirring of 3.75 ml of oil-soluble surfactants of Netanya NC, then enter in the small portions 1, the hydrophobic material brand POLYSIL-P1 and mix thoroughly, then dispense small amounts 85,75 ml of 0.5%aqueous solution of water-soluble surfactants of neonols AF9-12 and stirred until a homogeneous emulsion.

The emulsion obtained is characterized by a density of 965 kg/m3and a dynamic viscosity of 18.2 MPa·20°C.

Oil-driving ability of the emulsion is determined in terms of Tootmine of residual oil on the linear model for the homogeneous reservoir, representing a stainless steel column with a length of 220 mm, an inner diameter of 32 mm, the Column is filled with a mixture containing 95% quartz sand and 5% montmorillonite clay. Of the three main types of clay - kaolinite, hydrology and montmorillonite - with different degrees of swelling, as the clay component of the model was selected montmorillonite as having the greatest ability to swell. The model under vacuum saturated with water, the weight method is determined by the porosity and permeability of the core on the water.

After that in the model under pressure is pumped oil until until exit appears clean (without water) oil, is determined by the initial oil saturation. In the filtration works use natural oil density 842 kg/m3and a dynamic viscosity of 8.5 MPa with 20°C. the Initial displacement is performed with water (three pore volume) and determine the ratio of oil displacement by water. Then filtered through the model one pore volume of the test emulsion and three pore volumes of water, determine the growth rate and total fertility rate of oil displacement (see table 1).

Example 2. In the model layer with a permeability of water of 1.98 μm2and the initial oil saturation to 72.6% upload three pore volumes of water. Residual oil saturation after water flooding is 25.3%, the ratio of oil displacement by water - 0,64. Through the model one filter pore volume of the emulsion of the following composition, wt.%: hexane fraction -10,0; MPAW of Netanya H3 -1,5; POLYSIL-P1 -1,0; neonols AF9-12 -0,5; 1%aqueous solution of calcium chloride - other. After injection of one pore volume of the emulsion is pumped three pore volumes of water and determine the residual oil saturation, which is 14.6 percent. The total of oil displacement efficiency is 0.93, an increase of the displacement coefficient is equal to 0.29 (see table 2).

Studies of the filtration characteristics of emulsions of different composition and dynamic viscosity are shown in table 1 and 2.

As oil-soluble surfactant in the synthesis of 1-4, 13-15 in table 1 and table 2 use Neprinol NC; in the synthesis of 5, 6, 16-17 use Neonol AF9-4; in synthesis 7, 8, 18, 19 use Neftekhim; in the synthesis of the x 9, 10, 20, 21 use petroleum sulfonate with M M=700; in the synthesis of 11, 12, 22-27 use Sinol-EM.

As water-soluble surfactants in the synthesis of 1-4, 13, 14 in table 1 and table 2 use Neonol AF9-12; in the synthesis of 5, 6, 15-17 use SNO-ZB; as sadomasochistic surfactants in the synthesis of 7, 8, 18, 19 use ML-80, as a water-soluble anionic surfactants in the synthesis of 9, 10, 20, 21 use Sulfinol (Las); as sadomasochistic surfactants in the synthesis of 11, 12, 22-27 use ML-81B.

As modified on the surface of highly dispersed hydrophobic material in the synthesis of 1, 7, 10 in table 1 and table 2 use tetrafluoroethylene, in the syntheses of 2, 14 and 17 use of titanium dioxide in the synthesis 11,13 and 16 are used,49 silicon dioxide trademark Aerosil, in the syntheses of 3 and 18 use the iron oxide in the synthesis of 4, 15, 19 and 22 use Policy-P1, in the synthesis of 5 and 20 use of polyvinyl alcohol in the synthesis of 6, 21 and 23 use the chromium oxide in the synthesis of 7 and 27 use the aluminum oxide in the synthesis 8 and 24 use zinc oxide in the synthesis of 9,12 25 and 26 use Policy-DF.

The results of measurements of the dynamic viscosity show that with the introduction of highly dispersed hydrophobic material, the viscosity of the emulsion increases 1.3-2.0 times (see tables 1 and 2).

The results showed that the optimal concentration to obtain stable emulsions ablauts the liquid hydrocarbon-10-20 wt.%; oil-soluble surfactants of-1.0 to 5.0 wt.%; water-soluble or sadomasochistic surfactant minus 0.1 to 1.0 wt.%; highly dispersed hydrophobic material -0,1-2.0 wt.%; water - the rest.

The composition may contain calcium chloride in the amount of 0.3-5.0 wt.%.

When the content of the components of the emulsion: a liquid hydrocarbon of less than 10.0 wt.%; oil-soluble surfactant is less than 1.0 wt.%; water-soluble or sadomasochistic surfactant is less than 0.1 wt.%; highly dispersed hydrophobic material is less than 0.1 wt.% form an unstable emulsion, therefore, these concentrations are taken as the lower limit of concentration.

When the content of the components of the emulsion: a liquid hydrocarbon of more than 20.0 wt.%; oil-soluble surfactant more than 5.0 wt.%; water-soluble or sadomasochistic surfactant is more than 1.0 wt.%; highly dispersed hydrophobic material more than 2.0 wt.% does not lead to a significant increase of the displacement coefficient, therefore, to use compositions containing components above these concentrations is inappropriate.

The use of the proposed structure will increase the recovery of oil by increasing the hydrophobization of the reservoir rock and decreasing the surface tension at the phase boundary water - rock - oil and increase the cleaning action of the contaminated surface, and increasing the viscosity of the composition and increase the relative pronice the spine formation for hydrocarbon phase is compared to water.

Technology of application of the proposed structure is simple and is injected into a reservoir to reduce the injectivity of wells by 30-50%, the displacement of the composition from the wellbore into the reservoir with water or oil, the extract in the reservoir within 12-24 h and putting the well into operation for oil wells or injection water for injection wells.

0,66
Table 1.

Oil-driving ability of the proposed formulations and compositions-prototypes
ExampleContent, wt.%Dynamic viscosity, mPa.s atThe initial oil saturation,%The ratio of oil displacement
Liquid hydrocarbons-rodThe oil-soluble surfactantOdorant or/m Rast. PAVH/dyshidrotic mater.Water20°80°on the watergrowthtotal
1234567 89101112
The placeholder10,0 10,0 15,0 20,00,3

1,0

1,5

3,0
0,1

0,3

0,5

1,0
-89,6 88,7 83,0 76,014,0 13,4 10,5

6,8
20,8 19,7 18,7 21,268,5

64,0

78,2

73,5
0,71 0,58 0,65 0,690,15 0,18 0,20 0,190,87 0,75 0,85 0,88
The proposed composition
110,01,00,10,1and 88.815,322,573,60,710,160,87
210,01,50,51,0of 87.018,227,870,80,640,280,92
310,03,00,81,584,716,5/td> 30,275,80,640,290,93
410,05,01,02,082,0the 13.435,3to 78.30,640,300,94
515,01,00,10,1is 83.813,123,168,50,650,230.88
615,01,50,51,082,018,326,671,30,650,280,93
715,03,00,81,579.714,533,273,70,650,300,95
8150 5,01,02,077,012,829,371,20,650,320,97
920,01,00,10,178,810,621,872,90,630,250,88
1020,01,50,51,077,014..524,5to 75.20,630,300,93
1120,03,00,81,574,711,726,878,10,650,310,96
1220,05,01,02,072,09,821,376,00,280,94
Test cases
135,00,30,10,0594,55The emulsion is not stable
145,01,00,10,193,816,821,369,70,660,080,76
155,05,01,02,586,515,134,672,10,590,120,71
1610,00,30,10,0589,55The emulsion is not stable
Continuation of table 1.
12345678 9101112
1710,00,31,02,086,7The emulsion is not stable
1810,01,01,02,086,016,324,268,30,700,180,88
1910,06,01.22,580,313,838,873,60,630,300,93
2015,00,30,10,184,5The emulsion is not stable
2115,05,01,02,576,513,235,768,20,6 0,300,96
2220,00.30,10,179,5The emulsion is not stable
2320,05,01,02,072,010,629,565,40,650.280,93
2420,06,01,22,570.39,228,4to 78.30,660,260,92
2525,00,30,10,174.5The emulsion is not stable
2625,05,01,02,067,06,624,175,30,650,28/td> 0,93
2725,06,01,22,565,35,323,873,20,680.220,90

12td align="right" namest="c0" nameend="c18"> Continued table 2.
Table 2.

Oil-driving ability of the proposed formulations and compositions prototype (proposed formulations contain Policy: compositions 1-4 and 9-16-Policy-P1, compounds 5-8-Policy-SF).
ExampleContent, wt.%Dynamic viscosity, MPa·The initial oil saturation,%The ratio of oil displacement
Liquid hydrocarbonOil-soluble surfactantOdorant. or / m PAVH/var. hydrophob mater.CaCl2Water20°80°on the watergrowthtotal
1234 5678910111213
The placeholder10,0 10,0 15,0 20,00,3 1,0 1,5 3,00.1 0,3 0,5 1,0--89,6 88,7 83,0 76,014,0 13,4 10,5 6,820,8 19,7 18,7 21,2and 68.5 64.0 78,2 73,50,71 0,58 0,65 0,690,16 0,18 0,22 0,190,87 0,75 0,87 0,88
The proposed composition
110,01,00,10,10,388,5the 17.323,570,60,700,180,88
210,01,50.51,01,086,021,427,872,60,640,290,93
310,03,0 1.01,53,081,518,328,671,70,650,300,95
410,05,01,02,05,077,015,436,068,30,640,320,96
515,01,00,10,10,3to 83.513,6to 25.378,50,670,230,90
615,01,50,51,01,081,019,328,673,30,690,250,94
715,03,01.01.53,066,516,434,5 70.70,670,300,97
815,05,01,02,05,073,014,829,766,50,660,320,98
920,01,00.10.10,378,512,622,572,50,600,280,88
1020,01.50,51,01,076,015,531,272.30,650,300,95
1120,03,01,01,53,071,513,723,775.40,650,310,96
20,05,01.02,05,067,011,524,473,00,650,300,95
Test cases
135.00,30,10,10,3a 94.2The emulsion is not stable
145,01,00,10,10,393,518,523,567,70,670,110,78
155,05,01,02,56,080,516,336,370,10,680,150,83
1610,00,30,10,10,389,2The emulsion is not stable
12345678910111213
1710,00,31,02,55,081,2The emulsion is not stable
1810,01,01,02,05,081,018,525,171,60,700,200,90
1910,06,01,02,56,074,514,6a 38.573,50,700,260,96
2015,00,30,10,10,384,5The emulsion is not stable
2115,05,010 2,55,071,5the 13.436,968,20,660,300,96
2220,00,30,10,10,379,2The emulsion is not stable
2320.05,01,02,05,067,012,530,365.40,650,280,93
2420,06,01,22,56,064,310,834,468,60,660,280,94
2525,00,30,10,10,374,2The emulsion is not stable
2625.05,01,02,05,062,09,4 24,275,30.660,280,94
2725.06,01,22,56,059,36,225,470,50,660,260,92

1. Composition for extracting oil containing liquid hydrocarbon, a mixture of surfactants and water, characterized in that it contains as a surfactant oil, water or sadomasochistically surfactants and additionally highly dispersed hydrophobic material in the following ratio, wt.%:

Liquid hydrocarbon10,0-20,0
Oil-soluble surfactant1,0-5,0
Water-soluble or sadomasochistic SAS0,1-1,0
Highly dispersed hydrophobic material0,1-2,0
WaterRest

2. Composition for oil recovery according to claim 1, characterized in that it additionally contains calcium chloride in the amount of 0.3-5.0 wt.%.



 

Same patents:

FIELD: oil and gas production.

SUBSTANCE: invention aims at increasing productivity of oil- and gas-producing and injecting wells exposing high-temperature low-permeable oil reservoirs. In the treatment method according to invention including forcing enzyme substrate and separate enzyme into formation and creating conditions to enzymatically convert substrate into acid, geologic and productive characteristics for each interval of bottom zone are determined in order to pick out low-permeable intervals of oil reservoir for treatment, whereupon properties of enzyme substrate and separate enzyme as well as conditions for their pumping are chosen. Substrate utilized in the method is head fraction of methyl- and/or ethyl-, and/or butyl acetate production, to which aliphatic alcohols are added, and enzyme is an acid solution. Substrate is pumped simultaneously and/or before, and/or after pumping of enzyme, after which well is closed for some time and then opened and placed under predetermined operational conditions.

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25 cl, 1 tbl, 3 ex

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SUBSTANCE: invention provides a method of developing oil pool allowing production of oil from water-rich oil reservoir under difficult geological-tectonic conditions in the last development stage. In the method, neutral salt of carbonic acid and acid solution are forced into formation through injecting well with water generated in gas-liquid fringe created in formation. After pumping of neutral salt of carbonic acid, acid solution is pumped by portions alternating with water pumping. Before pumping of acid solution portions beginning by at least second portion, selective insulation of high-permeable formation intervals is performed. Aforesaid neutral salt of carbonic acid utilized is sodium carbonate aqueous solution or aqueous suspension of calcium carbonate and aforesaid acid solution is aqueous hydrochloric acid solution. Selective insulation of high-permeable formation intervals involves use of freshly prepared controllable viscoelastic composition containing water-soluble acrylic polymer, cross-linking agent, thermal stabilizer, surfactant, and water. Summary concentration of acid solution is determined from concentration of neutral salt of carbonic acid on the base of stoichiometric proportions.

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8 cl

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FIELD: oil and gas production.

SUBSTANCE: invention is intended for use during development of oil pools at different waterflooding phase for intensifying functioning of producing wells and increasing current oil recovery of formation. Composition contains, wt %: liquid hydrocarbon 10.0-20.0, oil-soluble surfactant 0.3-5.0, water-soluble or water-oil-soluble surfactant 0.1-1.0, superfine hydrophobic material 0.1-2.0, and water (the rest). Composition may further contain 0.3-5.0% calcium chloride. Oil recovery is increased owing to hydrophobization of formation structure, reduction of surface tension in water/rock/oil phase boundary, increase in detergent power of polluted surface, increase in composition viscosity, and increase of relative permeability of the formation for hydrocarbon phase as compared with water phase.

EFFECT: increased oil recovery.

2 cl, 2 tbl, 2 ex

FIELD: oil and gas production.

SUBSTANCE: composition contains 0.05-2.5% of hydrophobic power, 0.05-10% of ethylene/vinyl acetate copolymer, and organic solvent. Composition intensifies oil production owing to increased effective radius of formation bottom area treatment, prevention of moistening inversion effect upon fall of hydrophobic agent concentration, and, consequently, decreased volume of simultaneously produced water.

EFFECT: increased oil production, prolonged overhaul period, improved environmental safety, and lowered production expenses.

2 tbl, 3 ex

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes drilling product and force wells, forcing gas and water through force wells into separate zones of productive bed and extraction of hydrocarbons from product wells, forming separate gas, water and hydrocarbon saturated areas with major contents of respectively gas, collected therein for later use, water and hydrocarbons, periodical pumping of collected gas from formed gas saturated zones to water saturated zones, periodical pumping of water to gas saturated zones is performed. It is possible to pump collected gas to water saturated zones in form of gas-water mixture. It is possible to pump in passing gas of current deposit. It is possible to pump hydrocarbon or non-hydrocarbon gas from other sources. It is possible to pump water with admixture of specifically selected chemical reagents or compositions thereof. When gas content in water saturated zones reaches from 0.1 to 28% from water content in water saturated zones it is reasonable to generate resilient waves with frequency within range from 0.0001 to 45 KHz and amplitude within range from 0.02 to 2.8 MPa. It is reasonable to pump gas and water to separate areas of productive bed with concurrent generation of resilient waves in there with frequency within range from 0.0001 to 45 KHz and amplitude within limits from 0.02 to 2.8 MPa.

EFFECT: higher efficiency.

7 cl, 5 dwg

FIELD: oil extractive industry.

SUBSTANCE: method includes pumping of Sulfacella water dispersion into bed through force well and extraction of oil through extracting well, said dispersion additionally containing non-ionogenic surfactant AF9-12 with following ratio of components, in percents of mass: Sulfacella 0.5-1, AF9-12 0.01-0.1, water- the rest, while, before pumping of said dispersion mineralized water is pumped with total mineralization until 290 g/l in amount of 10% from volume of said dispersion, when pumping said dispersion prepared in fresh water, drain water is previously pumped, and when pumping said dispersion made from drain or bed water, bed water is previously pumped. For preparation of said dispersion fresh, drain or bed water is used with mineralization till 290 g/l.

EFFECT: higher efficiency.

2 cl, 2 tbl

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes examination of operation well for gas-condensation and periodical cleaning of face-adjacent well area from precipitating hydrocarbon condensate by pumping hydrocarbon condensate solvent into bed, exposure of well for period of condensate dissolution and following removal of received solution from face-adjacent area during well launch, as solvent binary mixture is used with unlimited mutual solubility of components, while at least one of them has unlimited mutual solubility with hydrocarbon condensate, and relation of binary mixture components is determined from previously built phase diagram of three-component system, formed during dissolution of hydrocarbon condensate. As binary mixture with unlimited mutual solubility of components a mixture of acetone and methanol is used, or chloroform and methanol, or chloroform and aniline, or chloroform and acetone.

EFFECT: higher productiveness.

2 cl, 3 ex, 6 tbl, 2 dwg

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes placing water solution of carnallite ore, either modified, concentrated, or mixtures thereof, said solution is used at maximal for well temperature conditions concentration and is pumped in amount, necessary and enough for forming a hydraulic column in well shaft above ceiling of productive bed and along remaining shaft height well is filled with water up to mouth. Carnallite ore used has composition, in percents of mass: potassium chloride 20.5-21.5; sodium chloride 19.5-22.5; magnesium chloride 24.0-27.0; crystallization water 29.5-30.5. Modified ore has composition, in percents of mass: potassium chloride 23.0-29.5; magnesium chloride 31.8-46.0; crystallization water - the rest. Said water solution is prepared by dissolving ore in fresh technical water, drained from oil preparation plants, or in bed water. In case of dissolving in bed water, the latter is pumped from well at temperature 60-90°C. During perforation of well, value of technological liquid hydraulic column above productive bed ceiling is taken equal to (1.03-1.07)-(1.05-1.1)Pb, where Pb - productive bed pressure. Water solution of carnallite ore is used at density 1.23-1.37 t/m3. During use of said solution as working body of force wells it is used at density 1.05-1.20 t/m3, and solution also contains swelling inhibitor for argillaceous component of oil and gas bearing bed, like oxyethylenedendiphosphone acid, in amount 0.05-0.15% of used dissolved ore mass.

EFFECT: higher efficiency.

1 cl, 4 ex

FIELD: oil industry.

SUBSTANCE: method includes treatment of face area of oil bed by hydrophobic agent in organic solvent and pressing oil from collector with following delivery of oil from face area of product well for treatment of oil terrigenic bed, in form of hydrophobic agent solution of ethylene copolymer with vinylacetate in ethylbenzol or fraction thereof is used in relation 1:1 - 10, treatment of face area is performed with following ratio of components, in percents of mass: ethylene copolymer with vinylacetate 0.05-2.0, ethylbenzol or fraction 0.05-20.0, organic solvent - the rest.

EFFECT: higher efficiency.

2 tbl, 2 ex

FIELD: mining industry and alternative fuels.

SUBSTANCE: coal is affected by methanogenic consortium of microorganisms with culture medium utilizing continuous pumping of culture medium through wells and tank wherein methanogenic consortium of microorganisms with culture medium is placed. Tank is installed on the surface above wells and pumping of culture medium from the bottom of tank through methanogenic consortium of microorganisms. Process produces biogas and coal-water fuel.

EFFECT: increased yield of biogas to continuously effecting culturing of microorganisms.

1 dwg, 2 tbl

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