Composition and method for acid processing of bottom hole formation zone

FIELD: oil-and-gas industry.

SUBSTANCE: composition for bottom hole formation zone processing comprises following elements in wt %: hydrochloric acid - 10.0-20.0, anionic surfactant, or non-ionic surfactant, or cationic surfactant, or mix thereof - 0.4-3.0, phosphorus compound AFON 300M - 0.01-15.0, solvent - 5.0-25.0, water making the rest. Proposed process comprises injection of said acid compound and its driving. Said compound is held to remove the reaction products. Note here that said acid compound is forced in pulse mode or in continuous mode in amount of 1-3 m3 per running meter of perforated depth of the bed at pressure allowable for this bed.

EFFECT: higher capacity of injection wells and fluid inflow due to decelerated reaction with bed rock, lower intensity of acid corrosion.

4 cl, 2 tbl, 17 ex

 

The invention relates to oil industry and can be used in acid treatment of bottomhole formation zone to increase injectivity of injection wells and well stimulation fluid from the reservoir in carbonate reservoirs.

Known composition for treatment of bottom-hole zone of carbonate reservoir, comprising in wt.%: hydrochloric acid 10-20, neinogennye surface-active agent (nonionic surfactant) 0.3 to 1.0, acetone 20-40 and the rest is water (see auth. SVID. No. 1513131, MKI E21B 43/27, publ. 1989).

This composition does not provide the required depth of processing bottom-hole zone of the well due to the high dissolution rate of the breed.

Known surface-active acid composition for treatment of carbonate reservoirs, comprising in wt.%: hydrochloric acid 6,0-24,0, spirit connection 5,0-30,0, detergents, technical TMS "Jenolen" 0,5-2,0, cationic surfactants, Ossipov or don-96 0,2-1,0, stabilizer iron of 0.5-3.0 and the rest is water (see RF Patent №2494136, MKI C09K 8/74, publ. 2013).

The disadvantage of this composition is the presence in the detergent composition of the technical "Jenolen" sodium silicate. During injection of the composition in the carbonate formation are allocated ions of Ca2+and Mg2+also in the stratal waters of these ions are present in the form of salts CaCl2and MgCl2. The presence of these ions �riodic to the formation of insoluble precipitation of silicate of calcium and magnesium.

The closest in technical essence and the task of the claimed composition is an acidic composition for treatment of bottom-hole zone, comprising in wt.%: galoidvodorodnykh acid 8,0-75,0, corrosion inhibitor of 0.5-2.0, phosphonic acid and/or nevoennoe ethoxylated surfactant of 0.5-2.0, solvent - other (see RF Patent №2100587, MKI E21B 43/27, publ. 1997).

Conducted laboratory studies have shown that non-selectivity of application of the composition for oil - and water-saturated interlayers of the productive formation.

The known method of oil recovery by injection of the acid composition, containing in wt.%: acid of 97.5-99,9 and the moderator of the reaction with the reservoir rock of 0.1-2.5, and compositions containing in wt.%: surfactant 5,0-16,0, liquid hydrocarbon 84,0-95,0, when the ratio of its volume to the volume of the acid composition from 2 to 4 (see RF Patent №2295635, MKI E21B 43/22, publ. 2007).

This method has a significant drawback. The technology involves injection of two solutions: the acid and hydrocarbon composition.

A method of processing bottom-hole zone of the well, including prodavcu easy oil-in zone of the productive formation is pre-prepared in distilled water with a temperature of 80-90°C solution of hydrochloric acid 5,0-20,0% concentration with surface-�active substance - ML-81 B, conducting technological exposure not more than 2 hours and the impact of depression (see RF Patent №2280154, MKI E21B 43/27, publ. 2006).

The known method involves pre-heating the acid composition to 80-90°C, which requires additional energy consumption and thus does not provide the required depth of treatment.

Known composition for treatment of bottom-hole zone carbonating collector, containing in wt.%: hydrochloric acid 7,0-19,0, solvent 10,0-45,0, the surfactant is 0.1-3.0, phosphoric acid 4,0-14,0 and the rest is water, and the method of acid treatment of bottom-hole zone of carbonate oil reservoir, including injection into the well above the acid with subsequent produvkoi in the depth of the formation and implementation of technological exposure (see RF Patent №2293101, MKI C09K 8/72, E21B 43/27, publ. 2007).

The disadvantage of this invention is the use of phosphoric acid, while reducing the concentration of hydrochloric acid due to its interaction with the carbonate rock forms the reservoir rock insoluble precipitates of calcium phosphate and magnesium, resulting in reduced treatment efficacy.

The closest to the technical nature of the achieved effect to the claimed method is a method of processing bottom-hole zone of oil formation comprising prodavcu acid reagent cher�W well in zone of the productive formation in the volumes providing excess filtration resistance in the remote from the well bore area of the reservoir above those in her bottom-hole zone, conducting technological exposure and the removal of waste products by impact of depression on the well depending on the ratio of injectivity of the well, and as the displacement fluid take fresh water or process water or process water with the addition of the cleaning agent or the oil from the oil-soluble emulsifier (see RF Patent №2346153, MKI E21B 43/27, C09K 8/74, publ. 2009).

This method is applicable for processing only terrigenous reservoirs and in the absence of the reagent composition of the retarder does not provide the required depth of processing bottom-hole zone.

The aim of the invention is to provide a composition for acid treatment of bottom-hole formation zone and method of acid treatment of bottomhole formation zone with its use, with high efficiency by slowing down the rate of acid reaction with the reservoir rock, reduce the intensity of acid corrosion, prevent secondary precipitation and the formation of the emulsion and provide the cleaning action of the composition.

This goal is achieved by creating a composition for acid treatment of bottom-hole formation zone containing hydrochloric acid, surface-active�e substance - Nonionic surfactant, or ANIONIC, or cationic surfactant is established, or a mixture thereof, Athos 300M, solvent and water, with the following ratio of components, wt.%:

hydrochloric acid10,0-20,0
ANIONIC surfactants, nonionic surfactant, cationic surfactant is established or a mixture thereof0.4 to 3.0
Athos 300M0,01-15,0
solvent5,0-25,0
waterthe rest,

moreover, the composition may further contain a corrosion inhibitor in an amount of 0.5 to 2.0 mass%, and in the method of acid treatment of bottomhole formation zone shall fix the above acid composition with its subsequent produvkoi and conducting technological exposure, and injection is carried out in pulse or continuous mode in volume at the rate of 1-3 m3LM perforated formation thickness at a pressure not exceeding allowable on the processed layer.

In an embodiment of the method, the injection of the acid composition to the treated layers is carried out pointervalue that allows you to adjust the volume and mode of injection depending on the filtration properties of the reservoir.

Hydrochloric acid is used in THE 2122-131-05807960-97 with am. 1-3,THE 2458-017-12966038-2002, THE 2458-264-05765670-99 with am. 1, THE 2458-526-05763441-2010, THE 2122-252-05763441-99 with am. 1-4, GOST 3118-77, GOST 857-95.

As surfactants can be used aminooctane surfactants, non-ionogenic surfactants, cationic surfactants or a mixture thereof, such as alkylsulfonate Volgoneft beyond 2481-308-05763458-2001; neftenol K (RD-1) TU 2483-065-17197708-2002; soluble NGL-205 brand And THE 0253-050-70351853-2008; alcapa 16.30 TU 2482-004-04706205-2005; neonol AF9-6, AF9-12 beyond 2483-077-05766801-98; Oksana CD-6, O-18, CA-21 to THE 2483-328-05763441-2000; OP-10 GOST 8433-81; sintimid-5 beyond 6-02-640-91; sintana DS-10, DT-7 on THE 6-14-577-88. The introduction of the surfactant contributes to the reduction of interfacial tension on the border with hydrocarbons, prevents the formation of water-oil emulsions and ensures compatibility of the composition and formation fluid, and also provides easier removal of waste products of the reaction and contamination of the formation.

Athos 300M is a mixture of sodium salts of phosphonic and hydrochloric acids, and is produced according to TU 2499-540-05763441-2012 with am. 2. The introduction of the Athos 300M helps to slow the rate of dissolution of carbonate rocks (table 1, example 16) by forming a film on the surface of the section of phases: carbonate rock - acid composition.

As a corrosion inhibitor may be used:

catesol 18-3 on THE 2482-005-49811-247-2010; metilen-2 SPT-500-2006; KI-1 Mr TU 2482-033-42942526-2002; PB-5 beyond 6-01-28-92; PKU-e p� THE 6-02-1299-85; The synola CQI beyond 2482-002-48482528-98; BA-6 to THE 6-02-1192-79; KI-1 on THE 6-046-89-381.006-97. The corrosion inhibitor is introduced into the composition in the use of inhibited hydrochloric acid.

As the solvent used organic solvents, such as isopropyl alcohol according to GOST 9805-84; propyl alcohol beyond 2632-106-4449379-07; methyl alcohol according to GOST 2222-95; technical ethyl alcohol GOST 17299-78. The use of Monohydric alcohols reduces the interfacial tension on the border with hydrocarbon that contributes to the creation of a homogeneous system upon contact and mixing of formation and injected reagents and prevents the formation of emulsions, blocking the channels of the filter.

The proposed composition for acid treatment can be prepared as in industrial production, and directly before use by serial dilution of the components in the claimed amounts. The ratio of components in the composition is determined experimentally as the most optimal for the task.

The proposed composition is a liquid from colorless to brown, stable during transportation and storage.

The proposed method of treatment consists in the injection into the well of the acid composition in volume at the rate of 1-3 m3per meter of the perforated formation thickness at a pressure �e exceeding permissible on the processed layer. At low injectivity of the well is carried out first exposure mode baths. The pumping of the acid composition can be produced in a pulsed mode, which allows to increase the depth of processing at low permeability, or in continuous mode, which ensures the continued movement of the bottomhole formation zone. To handle reservoir areas with different permeability funnel for pumping the acid composition is established on the level of the lower holes of the perforation. After injection of the acid composition it is forced into the formation process water or water-in-oil emulsion or oil in the amount of pump-compressor pipes and next conduct technology exposure for 4-6 hours depending on the temperature of the formation. In the case of high heterogeneity of filtration properties of the treated zones of the reservoir injection of the acid composition is carried out pointervalue. This fix allows you to adjust the volume and mode of injection of the acid composition. Extraction of the reaction products of the acid with the carbonate rock is carried out by swabbing.

To prove compliance of the claimed proposal, the criterion of "industrial applicability" here are examples of the preparation of a composition for acid treatment of bottom-hole formation zone and impact on the bottom zone and claimed�about trains. The results are shown in table 1.

Example 1 (inventive composition).

At 64.2 g of water are added with stirring 12.0 g Athos 300M, 0.8 g of oceanol CD-6, and 13.0 g of isopropyl alcohol and 10.0 g of hydrochloric acid (see table 1, example 1).

Examples 2-6 was carried out analogously to example 1, varying the types of components used and their content in the composition.

Example 7.

To 73,1 g of water are added with stirring 0.9 g Athos 300M, a mixture of 1.0 g of cintanya DT-7 and 1.0 g of alcapa 16.30, 11.0 g of methyl alcohol, 2.0 g of the corrosion inhibitor KI-1 and 11.0 g of hydrochloric acid (see table 1, example 7).

Examples 8-15 carried out analogously to example 7, by changing the types of components used and of the content in the composition.

Example 16.

To of 58.9 g of water are added with stirring 2.1 g of sintimid-5, 25,0 g of isopropyl alcohol and 1.0 g of corrosion inhibitor - Metylan (see table 1, example 16).

Example 17 (prototype).

60.0 g of hydrochloric acid 25% concentration are added with stirring 2.0 g of the corrosion inhibitor KI-1, then 2.0 g of nitrilotriethanol acid, 1.0 g of neonol AF9-12and 3.0 g of acetone (see table 1, example 17).

To study the kinetics of interaction of the compound with the carbonate used technique based on the measurement in time of the volume of carbon dioxide emitted during the interaction of the proposed composition with calcium carbonate (marble).

Installation with�faces from the flask, in which reaction occurs interaction, connected by flexible hose with Drexel, placed in a container of water. Released carbon dioxide from the vessel displaces water, which by a flexible hose comes in a foster volumetric capacity.

In every experience using a cube of size 1×1×1 cm, carved out of solid marble sample, which is placed in the flask with the test compound. The amount of composition 50 cm3the temperature of the experiment 20±2°C, the pressure is atmospheric. The speed of reaction of calcium carbonate with a composition of the following by changing the volume of evolved carbon dioxide over time. The coefficient of solubility of calcium carbonate calculated for dissolving half cube, based on the time allocation of 50% of the total volume of evolved gas:

where γ is the weight of the cube, g;

τ50- time allocation of 50% of the volume of carbon dioxide, h;

S is the surface area of the cube, cm2.

Table 1
The content of components, wt.%The solubility coefficient of the breed, g/cm2·h
№№Hydrochloric acid in conversion to HClAthos 300M Corrosion inhibitorSolventSurfactantsWater
12345678
110,012,0-13,0 isopropyl alcohol0.8 oxanol KD-664,23,45
212,00,5-7,0 methyl alcohol1.4 soluble NGL-205 grade A79,13,50
314,01,5-9.0 technical ethyl alcohol0,4 alcapa 16.3075,13,56
416,05,0 -15,0 isopropyl alcohol0.9 neonol AF9-6for 63.14,40
518,00,01-16,0 ethyl alcohol technical2.5 neonol AF9-1263,493,26
620,011,0-5,0 propyl alcohol3.0 neonol AF9-1061,04,00
711,00,92,0 KI-111,0 methyl alcohol1.0 sintana DT-7+1,0 alcapa 16.3073,13,46
818,00,041,4 BA14,0 propyl alcohol1,5 OP-1065,064,12
9 14,015,01.0 CI22,0 methyl alcohol1.5 sintana DS-10+1.5 soluble NGL-205 grade A453,11
1015,06,02.0 synola10,0 isopropyl alcohol0.5 oxanol CA-2166,54,55
1115,01,12,0 PB-512.0 technical ethyl alcohol1.1 neftenol K (RD-1)+1,1 OP-1067,73,12
1217,00,30,5 PKU-e8,0 propyl alcohol0.6 alkylsulfonate Volgoneft73,53,90
1320,00,52.0 Metylan12,0 isopropyl alcohol1.6 Oksana� O-18 63,94,15

2.1 sintimid-5
Continuation of table 1
12345678
1419,00,11.6 ketazol10.0 ethyl alcohol technical1.0 neonol AF9-668,33,15
15of 13.00,71.0 Metylan25,0 isopropyl alcohol2.1 sintimid-558,24,70
16of 13.0-1.0 Metylan25,0 isopropyl alcohol58,915,7
Prototype
1760,02,0 NTF2,0 KI-135,0 acetone1.0 neonol AF9-12-5,6

C - concentration of acid, the share units.

From the data presented in table 1, it is seen that the rate of dissolution of rocks by using the inventive composition compared to the composition of the prototype. When using the composition without component Athos 300M to the rate of dissolution increases with marble 3,11-4,55 g/cm2·h to 15.7 g/cm2·h, which suggests that the use of the component Athos 300M slows down the rate of dissolution of carbonate rocks by using the inventive composition.

To determine the filtration resistance change is carried out model tests. Take bulk lengths of 3.0-3.3 cm and a cross-section of 1.54 cm2filled with quartz sand with the addition of 10% calcium carbonate. The model is saturated with water, then subjected to displacement with oil, and then pumped back side of the test�th composition, stand up and displace oil. In water-saturated models after water is pumped test composition, stand up and displace water. Changing the filtration resistance is determined by the formula:

Q=K2(in,n)-K1(in,n)K2(in,n)100%a,

K2(b,n)and K1(b,n)- permeability models before and after injection of the composition, µm2. The test formulations are shown in table 2.

Table 2
No. p. p.Permeability, μm2The number of the injected compositionThe filtration resistance change, %
Before processingafter processing
1234 5
Water-saturated model
10,160,0942-41,0
20,310,249-22,6
Prototype
30,170,4217+147,0
Oil-saturated model
40,0260,1125+330,8
50,0350,26615+660,0
Prototype
60,0290,00417-86,2

From table 2 it is seen that when using the proposed composition is reduced filtration resistance and oil C�filtration ceases resistance through the water, that provides selective impact on the reservoir rock.

Here is an example of a specific application of the method of acid treatment of bottomhole formation zone using the proposed formulation.

Processing bottom-hole zone of the producing well for the purpose of intensification of oil production. Depth of 1700 m, the diameter of the casing 146 mm. Spacing productive carbonate reservoir 1611-1635 m, perforation intervals 1611-1615 m and 1630-1635 m. the Estimated volume of the reagent for treatment of the first zone is 8.0 m3second 10.0 m3. Allowable pressure on the first interlayer 4.0 MPa, the second - 3,0 MPa.

Treatment of the lower interval. Technological column of pump-compressor pipes (tubing), equipped with a funnel, down to a depth of 1635 m and packer at a depth of 1620 m. With an open annular valve tubing is filled with a reagent (4.9 m3). Close the tube off the valve, put the packer and pump the remaining reactant (5.1 m3). Prodavcu reagent is carried out with oil in the amount of 5.0 m3at a pressure of not more than 3.0 MPa. When the pressure of injection above the acceptable fix temporarily stop and resume after it fell. Conduct technology exposure for 6 hours. The development of the after treatment is carried out by swabbing of the plunger in the tubing string to the point of depression on the bottom of 3.0 MPa at zapakowane annular space�nste up to neutral pH of the produced output.

Treatment of the upper interval. The funnel is mounted on the depth 1615 m, packer at a depth of 1600 m. With an open annular valve tubing is filled with a reagent (4.9 m3). Close the tube off the valve, put the packer and pump the remaining reactant (3.1 m3). Prodavcu reagent is carried out with oil in the amount of 5.0 m3at a pressure of not more than 4.0 MPa. Conduct technology exposure for 6 hours. The development of the after treatment is carried out by swabbing of the plunger in the tubing string to the point of depression on the bottom of 3.0 MPa at zapakowane the annulus up to neutral pH of the produced products. Pull pumping equipment and allowed the well to the work. As a result of processing the oil rate increased from 1.5 to 7.0 tonnes.

When using the proposed composition for acid treatment of bottom-hole formation zone and method of acid treatment with its use in comparison with the prototype reduces the speed of reaction between acid composition from the reservoir rock, increasing penetration of the acid composition in low-permeability oil-saturated zone and increases the coverage of the formation impact, which, ultimately, leads to increased oil production.

1. Composition for acid treatment of bottom-hole formation zone that contains hydrochloric acid, a surfactant surfactants, phosphorous soy�the coalescing and the solvent, characterized in that the composition as a surfactant contains aminooctane ANIONIC or nonionic surfactant nonionic, or cationic, the cationic surfactant is established, or a mixture thereof, as phosphorus-containing compounds - Athos 300M and additionally water in the following ratio of components, wt.%:

hydrochloric acid10,0-20,0
ANIONIC or nonionic surfactant or a cationic surfactant is established, or a mixture thereof0.4 to 3.0
ATHOS 300M0,01-15,0
solvent5,0-25,0
waterelse

2. The composition according to claim 1, characterized in that it further comprises a corrosion inhibitor in an amount of 0.5-2.0 wt.%.

3. The method of processing bottom-hole formation zone, including the pumping of the acid composition and its subsequent produvkoi, conducting technological exposure and removal of the reaction products, characterized in that as the acid composition is injected composition according to claim 1 or 2, the pumping of the acid composition is carried out in pulse or continuous mode in volume at the rate of 1-3 m3LM perforated formation thickness at a pressure not exceeding the allowable for the given layer.

4. Method p� claim 3, characterized in that the pumping of the acid composition is carried out pointervalue in oil reservoirs.



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: in a carbonaceous oil deposit development method that includes drilling of horizontal wells with a core sampling from the productive formation, performance of core laboratory tests, acid treatment and multiple hydraulic fracturing of the formation in these wells, according to the invention the core is sampled at different sections along the whole length of the horizontal shaft. The sampled core is subjected to the laboratory tests to determine the fracturing pressure, at that the sections are identified along the shaft where the minimum fracturing pressure Pmin, MPa, and the maximum fracturing pressure Pmax, MPa is required. Each section is treated by acid; at that the acid concentration for each section is set as identical. During the acid treatment each treated section of the formation is isolated temporarily by packers from the remaining part of the well. Then multiple proppant hydraulic fracturing of the formation is made under pressure that does not exceed Pmax. At that at the sections, where Pmax is required the acid treatment is performed in a volume of Qmax, m3/m, at the sections where Pmin is required the acid treatment is performed in a volume not exceeding 10% of the maximum value. At the remaining sections the volume of the injected acid is defined proportionally to the obtained fracturing pressure in compliance with the following ratio: Qn=QminQmaxPminPmax(PnPmin)+Qmin, where Qn is the specific volume per meter of the thickness, which is required for the injection to the nth section of the formation along the horizontal shaft, m3/m, Pn is the required fracturing pressure at the nth section of the formation along the horizontal shaft, MPa.

EFFECT: improved sweep efficiency and increased oil recovery of the oil deposit.

1 dwg

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3 ex, 7 dwg

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EFFECT: improving efficiency of acid treatment of a well.

1 ex

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EFFECT: improving the acid treatment efficiency.

1 ex

FIELD: oil and gas industry.

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EFFECT: more effective exposure for greater-depth productive formations and cost saving.

1 tbl, 1 ex

FIELD: mining.

SUBSTANCE: method comprises the formation exposing by vertical well, tripping in the well on the pipe string of the water jet tool with even amount of injection nozzles and its placement in the preset interval of the formation, injection of driving fluid through injection nozzles of the water jet tool for caving in the formation, subsequent formation fracturing from caverns by the spray stagnation pressure in caverns. Meanwhile the water jet tool with a series of injection nozzles, located along the tool with the interval between nozzles in a line no more than two diameters of the casing is used. The water jet tool is rotated to the preset angle to change the direction of progressing of each subsequent fracture. The fractures are formed at driving fluid injection pressure in the casing below the side rock pressure. Before tripping of pipe string into the well in the bottom end of the water jet tool the rotating device and mechanical packer are installed. To compensate leakages and the wedging of fractures during the process of hydraulic formation fracturing an acid is added in volume equal to 20% of the volume of the driving fluid, the driving fluid is injected into the pipe string through the water jet tool into a cavern until fracturing, then into the annular space of the well an acid is injected to compensate the leakages and fracture wedging. The pressure of acid injection into annular space of the well amounts 85% from the pressure created in the pipe string during progressing of fracture, upon termination of progressing fracture and the wedging of fracture in the same direction raise a pipe string on 1 m, turn a pipe string on an angle applicable to a direction of forming of following fracture, and lowered, then the process operations are repeated.

EFFECT: improvement of accuracy of orientation of fractures, performance and reliability of fracturing of carbonate reservoirs.

3 dwg

FIELD: mining.

SUBSTANCE: method comprises the drilling of a horizontal well bore in oil saturated part of the productive formation of the well, tripping of the pipe string into the well, the forming of perforations and fractures using the a hydrofracturing of formation in the hole of horizontal well, successively, starting from the end of far from the vertical borehole axis. During the next hydrofracturing the section, through which hydrofracturing is performed, is insulated from another part of the string with a packer. During drilling of the horizontal well bore the permeability and porosity of rocks are determined and the intervals of the productive formation with low permeability and porosity of rocks are identified, and on completing of drilling the rock hydrofracturing pressure is determined in each interval of the horizontal borehole. Then the volumes of fracturing fluid and acid for each interval of the oil saturated part of the formation with low permeability and porosity are determined, then the pipe string is moved to the interval of the productive formation nearest to the borehole bottom, with low permeability and porosity, the mechanical packer is seated, from hole mouth using the pumping unit the gelled fracturing fluid is injected into the pipe string through nozzles of the water jet tool and reshape perforations, then, not stopping injection gelled of fracturing fluid on a pipe string, construct fracture pressure applicable to the given interval of the oil saturated part of the productive formation. After 30% drop of pressure of injection of gelled fracturing fluid in the pipe string the hydrofracturing fractures are formed, for this purpose into the annular space of the well an acid is injected at the variable flow rate ensuring maintaining of pressure of injection of gelled fracturing fluid in the pipe string 10% less than the fracture pressure for the given interval of the oil saturated part of the productive formation. The packer releasing is performed and the pipe string is removed from bottomhole to the mouth into the following interval of the oil saturated part of the formation with low permeability and porosity of rocks for forming perforations and conducting of a hydrofracturing of the formation with forming and progressing of fractures.

EFFECT: shortening time for formation hydrofracturing, improvement of performance and reliability of formation hydrofracturing.

3 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: method of treatment of the well bottomhole zone with low bed pressure means well washing with fresh water, renewal of the production formation perforation on the basis 10 holes per running meter of well, formations saturation with fresh water to 6MPa. The first portion of hydrochloric acid solution is injected to the well in amount 2.0m3 and is held under bath mode for 2 h. Injection to the formation is performed by four stages. At first stage 6 times pulse injection to the formation of specified first portion of hydrochloric acid solution is performed under cycle mode, including injection for 1 minute at pressure 1-6MPa and holding for 5 minutes for reaction, injection of the specified portion is completed under continuous mode until complete release of the well bore from the hydrochloric acid solution. At the second stage 6 times pulse injection to the formation of the second portion of the hydrochloric acid solution is performed in volume 3.0m3 under cycle mode, including injection for 1 minute at pressure 1-6MPa and holding for 5 minutes for reaction, injection is completed under continuous mode. Then process holding for 3 h is performed for reaction. At the third stage the third portion of the hydrochloric acid solution on the basis 0.5m3 per running meter of the production formation is performed under continuous mode at pressure 1-6MPa, and holding for reaction for 3 h is performed. At the forth stage the 6 times pulse injection to the formation of the second portion of the hydrochloric acid solution is performed on the basis 1.0m3 per running meter of the production formation under cycle mode including injection for 1 minute at pressure 1-6MPa and holding for 5 minutes for reaction, injection is completed under continuous mode. Holding for 3 h for reaction is performed, then reaction products are removed by swabbing.

EFFECT: improving treatment efficiency of the well bottom-hole zone.

1 ex

FIELD: oil and gas industry.

SUBSTANCE: according to the first version grouting composite contains oil-well Portland cement, water and additive that includes chlorine-containing setting accelerator, at that the composite contains sodium chloride and lithium carbonate as the additive with the following ratio of components, weight parts: Portland cement 100, sodium chloride 1.2-4.05, lithium carbonate 1.6-5.4, water 50-52, at that sodium chloride and lithium carbonate are taken in mass ratio 3:4 respectively and according to the second version the composite contains as the additive sodium chloride and biopolymer - reagent based on xanthane gum, at that sodium chloride and the above biopolymer are taken in mass ratio 10:1 respectively.

EFFECT: reduced setting time in conditions of low and normal temperature at simultaneous reduction of thickening time and increased flexural and compression strength at break in the same conditions.

3 cl, 2 tbl

FIELD: oil and gas industry.

SUBSTANCE: treatment method of underground hydrocarbon-containing formations involves the following: a) provision of a composition including a thickening initiator measuring pH, and a polymer capable of hydration in a certain pH range; b) pumping of a composition with pH value beyond the limits of the above pH range; c) activation of an action of pH thickening initiator for displacement of pH composition to the above range of its values, and d) provision of a possibility of increasing viscosity of the composition and shaping of a plug. According to another version, a processing method of underground hydrocarbon-containing formations involves the following: a) provision of a composition containing a polymer capable of hydration in a certain pH range; b) pumping of the composition with pH value beyond the limits of the above pH range; c) provision of a pH changing thickening initiator; d) activation of the action of the thickening initiator for displacement of pH composition to the above range of its values, and e) provision of a possibility of increasing viscosity of a composition and shaping of a plug. The invention has been developed in dependent claims.

EFFECT: improving efficiency of initiation and control of plug formation.

15 cl, 5 ex, 3 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to oil production, particularly, to from underground oil deposits. In compliance with this invention, at least one production well and one injection well can be used. Temperature distribution in the zone between said wells is analysed. In case temperature is distributed between said zones so that minimum temperature makes at least 20°C, maximum temperature does not exceed 320°C, while their difference makes at least 20°C, aqueous gel-forming preparations are injected via injection well that contain one or several chemical components. These preparations after injection in the deposit form gels under the effects of deposit temperature. Said preparations differ in type and/or concentration of chemical components. Chemical components and/or their concentration are selected to make gel-forming temperature and/or geol-forming time of the second and, if required, any other injected portion, differ from portions injected there before.

EFFECT: higher efficiency of oil extraction due to levelling of injectivity.

19 cl, 4 tbl, 7 dwg

FIELD: oil and gas industry.

SUBSTANCE: isolation method of water influx to well includes injection of organosilicone product to the isolated interval. At mixing to Devonian oil is added to organosilicone product; product 119-296I of B trademark is used as organosilicone product. The water is added with density of 1000-1190 kg/m3, the composite is mixed and injected to the isolated interval with the following ratio of ingredients, parts by volume: product 119-296I of B 100 trademark, water with density of 1000-1190 kg/m3 50-100, Devonian oil 10-20. The composite is reinforced by injection of liquid glass. At that buffer of fresh water is injected between the composite and liquid glass.

EFFECT: improved efficiency of water influx isolation due to regulation of time for gel formation of the injected composite and prevention of its early gel formation.

1 tbl

FIELD: oil and gas industry.

SUBSTANCE: acid composition for acid treatment of production and injection wells in carbonate and terrigenous reservoirs contains the following, wt %: hydrochloric acid (24% or 36%) 25.0-50.0, alkyl benzene sulphonic acid containing in an alkyl group 12-14 atoms of carbon, 0.1-2.0, citric acid 0.5-3.0, acetic acid 3.0-12.0, methyl alcohol 3.0-10.0, OS-20 preparation 0.5-2.5, IKU-118 corrosion inhibitor 1.0-5.0, hydrofluoric acid (40%) 0.0-7.5, Feriks iron stabiliser 0.0-5.0, and water is the rest. An acid treatment method of the bottom-hole zone of a carbonate, terrigenous or mixed formation involves pumping to the well of the acid composition in the amount of 1.0-5.0 m3 per 1 m of perforated thickness of the formation, its forcing-through into the formation, exposure for the reaction during not more than 8 hours and further removal of reaction products; as an acid composition, there used is the above said composition or its solution in fresh water at the ratio of the above said composition to fresh water, which is equal to 1:1-1:2 respectively. The treatment method is developed in claims.

EFFECT: creation of a composition for acid treatment, which has low corrosion rate at formation temperatures; considerable improvement of efficiency of acid treatment.

3 cl, 3 tbl, 4 ex

FIELD: oil and gas industry.

SUBSTANCE: water-based composite for temporary blocking of a productive formation comprises carboxymethyl cellulose, calcium chloride, dibasic ammonium phosphate, Morpen and water, as well it contains additionally potassium chloride and zinc stearate with the following ratio of ingredients, wt %: carboxymethyl cellulose 0.5-3.0, calcium chloride 3-12, dibasic ammonium phosphate 5-15, Morpen 0.05-1.00, potassium chloride 0.1-1.0, zinc stearate 0.1-5.0, water - up to the remaining weight.

EFFECT: improved efficiency of temporary blocking, maintenance of the productive formation permeability and porosity, improved workability of the blocking process due to the usage of the composite with perfected thixotropic properties promoting smooth cross-bonding in the process of the composite making and creation of high hydraulic resistance at blocking that prevent deep penetration of the blocking composite liquid phase to the formation.

1 dwg, 5 ex

FIELD: chemistry.

SUBSTANCE: grouting composition for insulation of zones of intensive absorption, includes Portland cement, semi-water gypsum, clay, foam generator and water, it also additionally contains calcium chloride, hydroxyethylcellulose and inert additive. As clay composition contains palydorskite, either montmorillonite or kaolin thermally activated mud powder, and as foam generator, and anionic or amphoteric surface-active substance SAS, with the following component ratio, wt.p.: Portland cement 76.0-91.9; semi-water gypsum 4.0-16.0; said clay powder 4.0-20.0, inert additive 0.1-4.0, said foam generator 0.1-0.5; potassium chloride 4.0-12.0; hydroxyethylcellulose 0.1-0.2; with water-solid ratio 0.6-1.0, which mixture of Portland cement, semiwater gypsum, said clay powder and inert additive constitutes 100 wt.p.

EFFECT: increased degree of insulating properties of claimed composition with insulation of intervals of absorption of well liquids in porous, cavernous fractured rocks, with opening of conducting channels from 1 mm to 10 mm, due to reduced density and high composition thixotropy, as well as due to formation of non-erodible and non-permeable cement stone with high adhesive properties to rock and increased strength characteristics.

4 cl, 2 tbl

FIELD: oil and gas industry.

SUBSTANCE: magnesia plugging material comprises a magnesium-containing binding agent, magnesium chloride and additives, at that the builder's calcined magnesite is used as the magnesium-containing binding agent, among the additives it contains a water-repellent agent being silicone oil and a hardening retarder being nitrilotrimethylphosphonic acid with the following ratio of components, wt %: builder's calcined magnesite - 70-80, magnesium chloride - 20-30, silicone oil - 0.1-0.5% above 100%, nitrilotrimethylphosphonic acid - 0.02-0.1 above 100%.

EFFECT: improved rate of the solution hardening and strength of the produced cement stone.

2 cl, 3 tbl

FIELD: oil and gas industry.

SUBSTANCE: cement slurry for cementing oil and gas wells consists of Portland cement, penetrating agent, fluid loss reducing agent, plasticising agent, antifoaming agent and water and differs in the fact that its contains PenetronAdmix as penetrating agent, any water-soluble cellulose ester as fluid loss reducing agent, lignosulphonate as plasticising agent, tributyl phosphate as antifoaming agent with the following ratio of components, wt %: Portland cement - 100, the above penetrating agent 3.0 in excess 100, the above fluid loss reducing agent - 0.03-0.1 in excess 100, the above plasticising agent - 0.3-0.7 in excess 100, tributyl phosphate - 0.01-0.1 in excess 100, water up to water-cement ratio - 0.38-0.42.

EFFECT: recovering integrity of cement sheath in annular space of wells when microcracks and microgaps are formed in it.

1 tbl

FIELD: oil and gas industry.

SUBSTANCE: in the development method of a non-homogeneous oil formation that includes injection to the formation of an aqueous solution of polyacrylamide (PAA), chrome acetate and magnesium oxide, the solution contains additionally a glass or basalt reinforcing microfiber pretreated by a 1-5% aqueous solution of AF9-6 or AF9-12 or constructional reinforcing microfiber (CRF) with the following concentration of components in the solution, wt %: PAA 0.3-1.0, chrome acetate 0.03-0.1, magnesium oxide 0.015-0.07, the above fibre 0.1-0.5.

EFFECT: increased efficiency of the method.

1 dwg, 2 tbl, 1 ex

FIELD: production and exploratory well drilling, particularly foaming drilling fluids used during penetration through incompetent rock intervals and during primary productive oil and gas deposit opening in the case of abnormally low formation pressure.

SUBSTANCE: foam composition comprises surfactant, foam stabilizer, water, water hardness control additive and lubricant. The water hardness control additive is sodium silicate. The lubricant is VNIINP-117 emulsion. The foam stabilizer is polyacrylamide, the surfactant is sulphonole. All above components are taken in the following amounts (% by weight): sulphonole - 0.8-1.5, sodium silicate - 0.2-0.5, polyacrylamide - 0.1-0.5, VNIINP-117 - 0.5-2, remainder is water.

EFFECT: reduced power inputs for well drilling, as well as reduced coefficient of friction between drilling tool and well wall.

1 tbl

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