Method for temporary productive reservoir interval plugging

FIELD: oil and gas industry, particularly temporary plugging of productive reservoir intervals, killing of wells having abnormally low reservoir pressure during well repair and to separate gas and oil intervals during plugging of multizone reservoir under combined development thereof and lost-circulation zone isolation during well drilling.

SUBSTANCE: method involves creating porous packer by injection of two compositions, namely polymeric solution and plugging liquid in well, wherein polymeric composition includes water-soluble polymer, cross-linking agent, foaming agent and water. The water-soluble polymer is polyacrylamide and/or carboxymethylcellulose and/or styromaleate. Above components are taken in the following amounts (% by weight): water-soluble polymer - 0.1-10, cross-linking agent, namely Cr2(SO4)3, Cr(C2H3O2)3, CrCl3, - 0.05-10, foaming agent, namely sodium alkyl benzene sulfonate, Neonol, sulfanole, Neftenol, - 0.1-5.0, remainder is water. The composition may additionally have gaseous agent, namely nitrogen, carbon dioxide, natural gas so that expansion ratio of the composition is 1.28-3.0. The plugging liquid is invert emulsion based on hydrocarbon phase, namely oil and/or hydrocarbon solvent, aqueous phase, namely water and/or salt solution of CaCl2 or NaCl2 or MgCl2 or BaCl2 in emulsifier presence. Above components are taken in the following amounts (% by weight) - hydrocarbon phase 15-18, aqueous phase - 72-82, emulsifier is 3-10. The composition is serially injected in well and followed by well killing liquid injection. Extreme dynamic shearing stress of polymeric solution is 25-110 Pa. Static shearing stress of porous packer is 50-410 Pa. Composition is formed on surface with cementing agent usage. The compositions are injected in laminar flow regime. Packer porosity is 10-50%. Plugging liquid volume is 2-4 m3, density thereof exceeds that of well killing liquid. The injection is carried out in two stages and time interval between the stages is not less than 30 min. Injection pressure is not higher than proof-test pressure. In winter unfreezing liquid is added to polymeric composition. Packer density is changed by heaving agent, namely metal salt CaCl2, KCl, MgCl2, BaCl2 solution addition. Packer is also used to create elastico-viscous screen to protect against mechanical impurities entering from exploitable reservoir or to isolate reservoirs during simultaneous or serial reservoir exploitation. Packer is retained for predetermined time interval.

EFFECT: possibility to maintain collecting properties of reservoir during current well repair and well workover.

20 cl, 5 ex, 3 tbl

 

The invention relates to the oil and gas industry, in particular to methods of temporary isolation intervals of productive formations, killing wells with abnormally low formation pressure during workover, and can be used in dividing the deposits of oil and gas, oil and water, in dividing jointly operated reservoirs, as well as isolation zones absorption during drilling.

There is a method of temporary isolation layer zones, including sequential injection of liquid glass and hydrochloric acid to precipitate on the bottom of the precipitate as oxide of silicon and subsequent destruction of its 40% alkaline solution [1].

The disadvantage of this method is the infiltration of the leachate injected fluids in the reservoir, reducing its permeability, and the use of concentrated solutions of corrosive substances (40% alkaline solution).

The closest solution is used as a prototype, is a method of temporary isolation of high-permeability zones of the bottom-hole formation zone, including the injection of polymers, salts of metals of variable valence to create a viscoelastic packer and its destruction acidic solution [2].

The disadvantage of this method is low static and dynamic shear stresses and viscosity at sukachevin and packer in the bottomhole formation zone at the initial moment. It is known that viscoelastic composition forms a spatial grid with high structural-mechanical properties after a certain period of time from the instant of joining up to several hours. Crosslinked viscoelastic composition cannot be injected into the reservoir, so pumped unstitched low-viscosity polymer solution with a period of increasing viscosity of not less than 30 minutes. During this time there is a partial spreading of the polymer solution in the pores of a header followed by joining in its pores, thus not provided a sufficient degree of conservation of reservoir properties in the current and capital repair of wells.

Object of the invention is a method of temporary isolation layer with a high index of ultimate dynamic shear stress of porous packer at the initial moment while also lowering its density. Gas bubbles prevent the penetration of porous material in the reservoir throughout the porous structure of the packer, which ensures the preservation of reservoir properties of the bottom-hole formation zone at the current and capital repair of wells during the renovations.

The problem is solved in that in the method of temporarily isolating interval of the reservoir, including the creation of porous packer by pumping into the well of the first to the position a polymer solution containing a water-soluble polymer, the crosslinker, the blowing agent and water injection into the well of the second composition is divisive fluid according to the invention the polymer solution as a water-soluble polymer contains polyacrylamide (PAA) and/or carboxymethyl cellulose (CMC), and/or a hydrolyzed copolymer of styrene and maleic anhydride (sodium styromaniac), having the structural formula of the type

in the following ratio, wt.%:

The specified water-soluble polymer0,1-10
The staplerof 0.05-10
The expander0,1-5,0
Waterthe rest,

and optionally gaseous agent at a ratio of increase of the specified polymer solution of 1.28-3,0,

and as divisive liquids using inverse emulsion of hydrocarbons - oil and/or hydrocarbon solvent, the aqueous phase is water and/or saline CaCl2or NaCl or MgCl2or BaCl2in the presence of the emulsifier Multala or Netanya NC, in the following ratio, wt.%:

The hydrocarbon phase15-18
The aqueous phase72-82
Emulsifier3-10,

the injection of these compositions perform consistently in a given volume and a given mode of injection, and after this injection are pumping kill fluid.

Ultimate dynamic shear stress specified polymer solution 25-110 PA, static shear stress of porous packer after structuring polymer solution 50-410 PA. The composition with the desired properties get on the surface with the use of cementing unit, and the injection is carried out in a laminar mode.

As the stapler using soluble trivalent chromium salt Cr2(SO4)3; Cr(C2H3O2)3; CrCl3. As the foaming agent can be used Las sodium, Neonol, Sulfinol, Neprinol VVD, as a gaseous agent, you can use nitrogen, carbon dioxide, natural gas.

Prestest porous packer is 10-50%indicated divisive liquid prepared with a density greater than the density of the kill fluid, injected volume specified divisive liquid - 2-4 m3. The injection of the specified polymer solution and the release of fluid is carried out in 2 stages with a break of at least 30 minutes for guests who compete porous packer.

The injection of the specified polymer solution passes through the tube space and/or through the annulus, the pressure of injection of these compositions does not exceed the pressure of the crimp.

In winter conditions specified polymer solution further comprises a non-freezing liquid (alcohols: isopropyl or methyl, or ethyl, or ethylene glycol, or triethylene glycol - TAG) in the amount of 10-15 wt.%.

The density of the porous packer regulate the addition of mass - solutions of salts of metals CaCl2or KCl or MgCl2or BaCl2.

Porous packer create over the level and/or level and/or below the level of the interval insulation in the pipe and/or in the annular space.

Porous packer retain for a specified period of time plugging wells and/or the isolation of water inflow, and/or time prevent cross-flows, and/or exploitation of well installation and/or operation of the reservoir, and/or operation of the well.

Porous packer can additionally be used to create a viscoelastic filter from solids, removed from the exploited reservoir or for zonal isolation while simultaneously separate and/or sequential exploitation - the extraction of these fluids and/or downloading them working agent.

The essence of the proposed method which consists in the following. To preserve the reservoir properties of the bottom-hole formation zone at the current and capital repair of wells stopped in the well before pumping inverse emulsion and liquid damping - create a porous packer of a porous polymeric material. For this purpose, we first prepare a solution of water-soluble polymeric material, a binder and speciates with gaseous agent to the extent necessary to fill part of the casing opposite the isolated interval.

To avoid penetration of easily filterable fluid damping in porous material of the packer during the framing above it is divisive liquid - reverse emulsion, which is characterized by high values of plastic viscosity and ultimate dynamic shear stress, which prevents the penetration of divisive liquid in the porous material of the packer, with one hand. On the other hand, the reverse emulsion - dispersed two-phase system with external hydrocarbon phase, that is not soluble in water and saline solutions, which are well kill fluid.

To eliminate gravity and sedimentation processes between the composition of the packer and oil, gas and water porous material has a low density in terms of overall compression.

Porous packer with the AMI physico-chemical properties is dispersed two-phase system the polymer solution and the gas. The stability of such a solution is determined by the ability to retain particles of the dispersed phase is a gas vesicles in suspension, which is characterized by the value of the static shear stress. Static shear stress determines the strength of the structural grid, i.e. the stability of the dispersed system to adhesion of gas bubbles.

To prevent the ascent of gas bubbles porous packer is prepared with a high value of the static shear stress.

Physico-chemical properties at different content of the porous components of the packer and viscoelastic composition (prototype) after 5 minutes after preparation are shown in table 1.

Within 20-30 minutes in situ at elevated temperature and pressure to harden the porous structure of the packer. This is explained in the following. The proposed porous packer forms a durable a single structural system, which can be represented in the form of two hierarchical structures. The first structure - water, water-soluble polymer and crosslinker, the second structure - water, foaming agent and gas bubbles, which increases the structural strength of the grid and to improve thermal stability. In laboratory conditions, porous packer starts to break down at a temperature of more than 90°C. This increase components the stability can be explained by the structure of the obtained porous packer. The increase of temperature and pressure conducive to the formation of a strong structural grid of the gaseous agent in the presence of a blowing agent and water, due to the expansion of gas bubbles, and the water-soluble polymer and crosslinker are structured, forming a cross connection, preventing the release of gas bubbles. Thus, a viscoelastic porous packer with reduced density and gravitational sedimentation sustainable, not filtered into the reservoir.

Disconnecting the fluid allows the fluid damping to disturb the equilibrium of the resulting system, blocking packer.

Physico-chemical properties with different content components divisive fluid are shown in table 2.

The minimum volume of the porous material is determined based on the reservoir pressure, the location of the packer and structural-mechanical properties of a porous material (in this case the maximum dynamic shear stress) and is calculated by the formula:

The results of the calculation of the volume of the porous packer shown in table 3.

After repairs porous packer and divisive liquid takes place with the well completion freely.

For the process of plugging the wells sequentially perform the following operations.

The first solution is oppozitsii porous packer or "Aerogel" is prepared as follows: in half of the calculated amount of water estimated number vodorastvorimogo polymer and blowing agent. In the second capacity, prepare a solution of the crosslinker. To do this, in the remaining part of water, add the estimated amount of the staple. Then both solutions are combined in a vessel and cementing unit and stirred until complete mixing and straight from the container Assembly CA-320 pumped into the well with the help of the compressor.

Consistently prepare the second composition - the composition of the release fluid. The inverse emulsion is prepared in the aggregate cement mixing components and upload a pre-prepared solution into the well, with over a porous packer. Fill the well with fluid damping. After repairs divisive fluid and porous packer is issued when the well completion freely.

The proposed method of temporary isolation interval of the reservoir, including the creation of a porous polymer packer before download divisive fluid and fluid damping with subsequent development wells, enables to keep the reservoir properties of bottom-hole formation zone, significantly reduces the startup time of the wells in operation after the current and capital repair of wells under conditions of abnormally high and low values of reservoir pressure.

Specific examples of implementation of the proposed method.

The method was tested in promyslovyh conditions on van Yogan field in Western Siberia.

Example 1. Complicated killing.

The work was carried out at well # 3654 Bush 1043. The purpose of the repair is complicated by the killing. A four-time work on the prototype well absorbed. The well was stopped at the exit mouth of the gas. Pumped into the annular space 12 m3solution with a density of 1020 kg/m3shut down failed (outlet gas). Was added a solution of re (35 m3solution with a higher density of 1050 kg/m3). Circulation no - absorbs well, drown failed.

Decided to apply the proposed method. Prepared the first composition. Dissolved in the pump cementing unit CA-320 33,2 kg CMC in 231,9 liters of water. In an intermediate tank 500 l of dissolved blowing agent Las sodium - 0.3 kg in 100 l of water. Using compressor made barbotirovanie nitrogen in the solution of the blowing agent to achieve a foam volume of 200 L. has fed from the pump cementing unit prepared solution of the polymer in the resulting solution of the foam. Mixing solutions, added crosslinker (16.6 kg) Cr2(SO4)3. The resulting composition is 0.52 m3porous packer (with multiplicity increase of 1.3) was pumped at a pressure of 5 MPa (three times less pressure molding) process the string of pipe (tubing) to the interval isolation. When the volume is estimated column height was 31 m i.e. packer was created at the interval isolation. For structuring packer survived 35 minutes. The calculated porosity of the obtained packer is 30%. The time stability of the packer 48 hours.

In the pump cementing unit CA-320 circulation within 30 minutes prepared a second composition in a volume of 2 m3mixing oil 419,3 liters in the presence of the emulsifier of Netanya NC (200 l) with 1580,7 liters of an aqueous solution containing 100 kg CaCl2. The density of the resulting solution is divisive liquid - 1138 kg/m3; static shear stress - 12.0 PA; viscosity plastic - 343 MPa·S. Pumped divisive fluid sequentially for porous packer, then crushed the kill fluid with a specific gravity of 1080 kg/m3.

The injection was made in the course of 20 minutes with a flow rate of 290 m3/day, through the drill pipe with a diameter of 73 mm and the rate of solution viscosity of 4 PA·0.8 m/s, Re=7,3 that characterizes the mode of injection as laminar.

The well was stopped. Replaced the pump. After 48 hours have mastered well. Just got the oil flow.

Example 2. The creation of a viscoelastic filter from solids.

The work was carried out at well # 900, where layer 1 PCs Megion field imposed solids (content in crude production 853 mg/l).

Analogion the example 1 was prepared 2 songs.

The first composition in an amount of 193, 2 l contains: water-soluble polymer is polyacrylamide (PAA) - 11.6 kg; staple CrCl31.2 kg; the expander - neprinol VVD - 4.8 kg; water - 193,2 l, the volume of the gaseous agent - natural gas - 200 litres, which provides 50%porosity. The height of the packer - 112 m Time stability of the obtained packer 3 months.

Pumped her through the process pipe with nadavlivanie 80-90 l partially in the reservoir.

The second volume of 2 m3contains: hexane (hydrocarbon solvent) with the emulsifier amaltal (140 l) - 487,9 liters; the aqueous phase 1512,1 l MgCl2(530,6 kg). Properties obtained divisive liquids: static shear stress and 15.3 PA, the viscosity of the plastic - 480 MPa·s; density - 1286 kg/m3.

The share of the kill fluid - 1050 kg/m3. The density of the downhole fluid 1020 kg/m

The injection was made in the course of 25 minutes with a flow rate of 22.9 m3/day through the drill pipe with a diameter of 73 mm, the injection Pressure 3 MPa, which is 25% of the pressure of the crimp. The speed of solution viscosity 6 PA·amounted to 0.06 m/s, Re=0,374 that characterizes the mode of injection as laminar. The well was ostavleno on structuring (hardening of the structure).

Influx after 24 hours. The content of solids decreased from 853 mg/l to 20 mg/L.

Example 3. Killing in the winter period is.

The work was carried out on the well 4449 Bush 3 North-Pokursky field.

Analogously to example 1 was prepared 2 songs. The first composition comprises: 559 l of water; a water-soluble polymer is sodium styromaniac - 0.6 kg; staple - (Cr(C2H3About2)3- 6 kg; the expander - Neonol - 24 kg; weight MgCl2- 37 kg; non-freezing liquid (isopropyl alcohol) - 75 kg; volume of the gaseous agent is carbon dioxide - 1100 litres, which provides 50%porosity. The time stability of the obtained packer 16 days. The ratio of foaming is 2.5. The height of a column of porous packer 112 m

The second volume of 3 m3contains: oil - 908,3 liter; emulsifier amaltal - 240 l; aqueous phase 2091,7 L. Properties obtained divisive liquids: static shear stress and 15.3 PA, the viscosity of the plastic - 480 MPa·s; density - 1480 kg/m3.

The specific weight of the fluid damping 1050 kg/m3. The density of the downhole fluid 1020 kg/m3.

The injection was made within 30 minutes with a flow rate of 72 m3/day. Packer create in the annulus. The injection pressure of 3.5 MPa, which is 50% of the pressure of the crimp. The speed of solution viscosity of 2 PA·0.2 m/s, Re=3,64 that characterizes the mode of injection as laminar. The well was stopped on the structuring of 3 hours, were then produced the modern repair wells. Ten days later, well mastered and got the oil flow in the same day.

Example 4. Killing the well with two working layers.

Well # 1079 Bush 56 Atinskogo field work two layers. Stratum B8absorbs fluid damping.

Analogously to example 1 there were prepared two songs.

The first composition comprises: a water-soluble polymer is polyacrylamide (PAA) - 45 kg, the staple CrCl3- 0.5 kg, the expander neprinol VVD - 48 kg; water - 972,4 l-freezing agent (triethylene glycol) - 150 kg, the volume of the gaseous agent is a nitrogen - 2600 liters. The rate of increase equal to 3, which provides 66%porosity. The height of the packer 232,6 m, i.e. packer was created at and above the interval isolation. The time stability of the obtained packer 2 days.

The second composition 2 m3contains: oil - 1038,5 l dissolved emulsifier by multala (200 l); the aqueous phase is 2961,5 liters of water and 903,5 kg NaCl. Properties obtained divisive liquids: static shear stress - 12,8 PA, the viscosity of the plastic - 356 MPa·s; density - 1258 kg/m3.

For damping layers with simultaneous operation of two reservoirs produced injection for 35 minutes with a flow rate of 56 m3/day, through the drill pipe with a diameter of 73 mm, the injection Pressure 3 MPa, which is 25% of the pressure of the crimp. The speed of solution Vascos the d 4 PA· with amounted to 0.15 m/s, Re=1,4, which characterizes the mode of injection as laminar. The well was plugged and stopped at structuring for 5 hours.

After this was repaired with the replacement of a submersible pump. Well mastered after 56 hours.

Example 5. The use of porous packer to separate the layers with the purpose of their research.

Well No. 449 Bush 3 Aganskoye field.

Analogously to example 1 was prepared 2 songs.

The first composition comprises: a water-soluble polymer - PAA - 10,1 kg, staple CrCl3- 1.63 kg, the expander - alkylbenzenesulfonate sodium - 2.5 kg; water - 504,6 l, the volume of the gaseous agent - natural gas - 260 liters. The rate of increase of 1.5, which provides 33%porosity. Time stability of porous packer 15 days.

The second volume of 2 m3contains: a solution of the oil with emulsifier-multala (98.2 l) 419,8 liter; the aqueous phase is water 1580,2 l with 243,2 kg BaCl2. Properties divisive liquids: static shear stress is 14.8 PA, the viscosity of the plastic - 520 MPa·s; density - 1286 kg/m3.

The injection was made in the course of 25 minutes with a flow rate of 29 m3/day through the drill pipe with a diameter of 73 mm, injection Pressure and 4 MPa, which is 33% of the pressure of the crimp. The speed of solution viscosity of 1.5 PA·0,08 m/s, Re=1,97 that characterizes the mode for acci as laminar.

The well was stopped on structuring.

The upper level divisive fluid was on 10 meters below the perforated interval the top of the reservoir.

Then spent hydrodynamic studies for the upper reservoir. Similarly, after the installation of porous packer between the upper and lower layers held hydrodynamic investigations of the lower reservoir.

Then, on the basis of the received parameter data layers have translated well on dual operation.

The proposed method of temporary isolation interval of the reservoir, including the creation of a porous polymer packer before download divisive fluid and fluid damping with subsequent development wells, enables to keep the reservoir properties of bottom-hole formation zone, significantly reduces the startup time of the wells in operation after the current and capital repair of wells under conditions of abnormally high and low values of reservoir pressure.

Sources of information

1. A.S. 1423726, CL EV 33/13, 1988

2. A.S. USSR 1035194, CL EV 33/13, 1983 prototype.

1. Method of temporarily isolating interval of the reservoir, including the creation of porous packer way of the injection into the well of the first composition a polymer solution containing a water-soluble polymer, the crosslinker, the blowing agent and water injection into the well of the second composition is divisive fluid, characterized in that the polymer solution as a water-soluble polymer contains polyacrylamide and/or carboxymethyl cellulose CMC, and/or sodium styromaniac in the following ratio, wt.%

The specified water-soluble polymer0,1-10
The staplerof 0.05-10
The expander0,1-5,0
WaterRest

and optionally gaseous agent at a ratio of increase of the specified polymer solution of 1.28-3,0,

and as divisive liquids using inverse emulsion of hydrocarbons - oil and/or hydrocarbon solvent, the aqueous phase is water and/or saline CaCl2or NaCl or MgCl2or BaCl2in the presence of the emulsifier Multala or Netanya NC in the following ratio, wt.%:

The hydrocarbon phase15-18
The aqueous phase72-82
Emulsifier3-10

download MC is related compositions perform consistently in a given volume and a given mode of injection, and after this injection are pumping kill fluid.

2. The method according to claim 1, characterized in that the maximum dynamic shear stress specified polymer solution 25-110 PA, static shear stress of porous packer after structuring polymer solution 50-410 PA.

3. The method according to claim 1, characterized in that the composition with the desired properties get on the surface with the use of cementing unit, and the injection is carried out in a laminar mode.

4. The method according to claim 1, characterized in that the stapler using soluble trivalent chromium salt Cr2(SO4)3or Cr(C2H3About2)3or CrCl3.

5. The method according to claim 1, characterized in that as the foaming agent used Las sodium and/or Neonol, and/or Sulfinol, and/or Neprinol VVD.

6. The method according to claim 1, characterized in that the gaseous agent using nitrogen or carbon dioxide, or natural gas.

7. The method according to claim 1, characterized in that the porosity of the porous packer is 10-50%.

8. The method according to claim 1, characterized in that the specified divisive liquid prepared with a density greater than the density of the liquid damping.

9. The method according to claim 1, characterized in that the injected volume specified divisive liquid 2-4 m3.

10. The method according to claim 1, ex is different, however, that the injection of the specified polymer solution and the release of fluid is carried out in 2 stages with a break of at least 30 min for structuring porous packer.

11. The method according to claim 1, characterized in that the injection of the specified polymer solution passes through the tube space and/or through the annulus.

12. The method according to claim 1, characterized in that the injection pressure of these compositions does not exceed the pressure of the crimp.

13. The method according to claim 1, characterized in that in winter conditions specified polymer solution further comprises a non-freezing liquid in the amount of 10-15 wt.%.

14. The method according to item 13, characterized in that as a non-freezing liquid use alcohol: isopropyl or methyl, or ethyl, or ethylene glycol, or triethylene glycol - TAG.

15. The method according to claim 1, characterized in that the density of the porous packer regulate the addition of mass - solutions of salts of metals CaCl2or KCl or MgCl2or BaCl2.

16. The method according to claim 1, characterized in that the porous packer create over the level and/or level and/or below the level of the interval isolation.

17. The method according to claim 1, characterized in that the porous packer creates a pipe in space and/or in the annular space.

18. The method according to claim 1, characterized in that the porous packer retain for a specified period of time and - time plugging wells and/or the isolation of water inflow, and/or time prevent cross-flows, and/or exploitation of well installation and/or operation of the reservoir, and/or operation of the well.

19. The method according to claim 1, characterized in that the porous packer additionally used to create viscoelastic filter from solids, removed from the exploited reservoir.

20. The method according to claim 1, characterized in that the porous packer additionally used for zonal isolation while simultaneously separate and/or sequential exploitation - the extraction of these fluids and/or downloading them working agent.



 

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2 cl, 1 dwg

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EFFECT: increased production well output along with water influx restriction, improved isolation quality and reduced repair costs.

FIELD: oil production, particularly to isolate casing annulus and tubing-casing annulus with the use of plugging polymer-based compositions curable in reservoir conditions.

SUBSTANCE: method involves injecting isolation material in injection or production well, wherein the isolation material includes polymer curable in reservoir conditions; forcing thereof through well and holding the composition inside well for time enough to cure and strength development. The composition is water-soluble polymeric composition including acetone-formaldehyde resin in amount of 80.0% by weight, sodium carbonate or potassium carbonate in amount of 4.0-7.0% by weight, chemical reagent Okzil-SM in amount of 0.5 % by weight, remainder is water or 30% NaCl solution. If reservoir temperature is 50°C or less alkali, namely sodium hydroxide NaOH, in amount of 0.1-2.5% by weight is additionally mixed with above composition. In the case of plugging operation performing in high-pressure wells fine inert filler, namely industrial talc, is added in amount of 30-100% of composition volume to be injected.

EFFECT: possibility of casing annulus and tubing-casing annulus plugging in temperature range of 20-90°C.

3 cl, 3 tbl, 3 dwg

FIELD: oil industry, particularly preventing gas- or water-coning phenomena, for instance the formation of a conical column of gas or water around wells.

SUBSTANCE: method involves supplying gel-forming material in isolation zone in one step up to full isolation zone saturation; injecting 27% hydrochloric acid at rate of 2-6 l/sec. The gel-forming material is pulp of syenite alkali-aluminum concentrate in calcium chloride solution having specific weight of not more than 1.2 g/cm3 and taken with volumetric ratio of 1:1. The gel-forming material is supplied at rate of not less than 3 l/sec. The gel-forming material and hydrochloric acid mass ratio is 1:1.

EFFECT: increased technological effectiveness and improved efficiency due to full isolation zone saturation with gel-forming material.

2 ex

FIELD: oil production industry, particularly to isolate water-permeable formation intervals during well repair and plugging operations.

SUBSTANCE: method involves injecting aqueous solution of high-modulus sodium silicate and acid gel-generation agent; leaving thereof in well for time enough for gel forming and creating isolation screen having thickness determined as L=(Pd·K)/grad(Ps), where L is isolation screen thickness, m; Pd is rate of differential pressure drawdown in flooded productive reservoir area, MPa; K is load factor of isolation screen, K=1.2; grad(Ps) is gradient of initial pressure of reservoir water filtration through screen, wherein grad(Ps) is equal to 7.7-40.0 on experimental investigation data, MPa/m. The high-modulus sodium silicate is colloid sodium silicate, the acid gel-generation agent is liquid waste obtained during electrochemical metal coating application. Above components are mixed to form solution having pH value of 3-9.

EFFECT: increased efficiency due to increased strength of obtained isolation screen due to usage of solution having optimal gel forming time and determining of optimal isolation screen thickness, reduced time of isolation screen forming, extended range of gel forming materials along with improved ecology and possibility to utilize industrial waste.

1 ex, 2 tbl, 4 dwg

FIELD: oil and gas production.

SUBSTANCE: invention relates to insulating formation water inflow in gas and gas condensate wells with the aid of coltubing techniques. In particular, flexible conduit is descended through the tube space of well operated under pressure to the bottom with the aid of coltubing installation. Latches on tube and annulus spaces are opened. Well hole is filled through flexible conduit with gas condensate. Grouting mortar is prepared in preparation block by mixing cement mortar with setting retardant and mortar flowability enhancer in a calculated amount needed to prevent formation water inflow. Further, flushing fluid, e.g. methanol, is pumped through flexible conduit in amount constituting 0.3-0.6 volume of flexible conduit. Annulus space is closed and grouting mortar is pumped through flexible conduit in amount required to fill well hole in interval of water-inflow part of formation. When grouting mortar in hole rises to specified height, tube space is closed and grouting mortar contained in flexible conduit is forced into water-inflow part of formation by in series pumped flushing fluid and displacing solution: for example first methanol in amount 1.0-1.3 volumes of flexible conduit and then gas condensate in required amount, which however does not exceed internal volume of flexible conduit, until grouting mortar begins being pumped in amount of 0.3-0.5 volumes of flexible conduit. Then tube and annulus spaces of well are opened and gas condensate begins being simultaneously pumped into tube and annulus spaces in order to prevent rise of grouting mortar therein above interval of the water-inflow part of formation. Thereafter, bottom of flexible conduit is raised by 1 m above indicated interval and excess of grouting mortar is cut and washed away with gas condensate passed through flexible conduit into tube space, where excess grouting mortar remains in fluid state. After cement setting expectation time, flexible conduit is descended to the top of cement column and tests the latter for strength applying 4.0-5.0 kN loading by means of injector of coltubing installation through flexible conduit. Finally, cement bridging is subjected to hydraulic pressurization and flexible conduit is removed from well.

EFFECT: enabled formation water inflow insulation without killing of well and restricted pollution of water-inflow part of formation.

3 cl, 1 dwg

FIELD: oil and gas chambers construction.

SUBSTANCE: method includes pumping of portion of water-absorbing acryl polymer, exposure of it in a well, pumping of second portion of same polymer, tempered on fresh water with concentration 1-20%, buffer of fresh water dries up, and before and after pumping of second portion of water-absorbing polymer, tempered on hydrocarbon liquid with concentration 10-20%, buffer of hydrocarbon liquid is pumped in, besides, said 2-portion systems are pumped into well multiple times.

EFFECT: higher efficiency.

1 ex

FIELD: oil and gas production.

SUBSTANCE: bottom area of formation is treated with hydrophobic agent, in particular solution of ethylene/vinyl acetate copolymer expressed by general formula [-CH2-CH2-C(CH3COO)H-CH2-]n, where n=7000-10000, in hydrocarbon solvent.

EFFECT: increased source of inexpensive hydrophobic agents with improved adhesion properties, intensified oil recovery due to increased depth of penetration of hydrophobic agent into formation, improved environmental conditions in development of oil formations, and reduced oil production expenses.

2 tbl, 2 ex

FIELD: oil and gas production.

SUBSTANCE: composition is made up of 90.0-95.0% sodium silicate solution with concentration 1.36 g/cm3 and silica modulus 3.0, 3.0-8.0% alkali metal silicofluoride, 1.0-4.0% wood flour, and 1.0-4.0% triacetine. Composition can be used during repair operations on oil production stings, when disabling formations, and when confining water inflow.

EFFECT: increased insulation capacity of grouting compositions.

1 tbl

FIELD: oil extractive industry.

SUBSTANCE: method includes pumping, in carrying liquid - waterless mixture of oil products containing waterless oil, of powder-like water-soluble polymer and connector in amount of 0.05-0.2% for mass of carrying liquid or 30-100% for mass of power-like water-soluble polymer, as said mixture a mixture of waterless oil and light oil products processed in relation 0.1:9.9-9.9:0.1 is used, and as connector - dry aluminum nitrate, chrome nitrate, iron nitrate, magnesium nitrate, barium nitrate, calcium nitrate or their mixtures.

EFFECT: higher efficiency.

2 tbl

FIELD: oil extractive industry.

SUBSTANCE: method includes pumping, in carrying liquid - waterless mixture of oil products containing waterless oil, of powder-like water-soluble polymer and connector in amount of 0.05-0.2% for mass of carrying liquid or 30-100% for mass of power-like water-soluble polymer, as said mixture a mixture of waterless oil and light oil products processed in relation 0.1:9.9-9.9:0.1 is used, and as connector - dry aluminum acetate, chrome acetate, iron acetate, magnesium acetate, copper acetate, barium acetate, manganese acetate, calcium acetate or their mixtures.

EFFECT: higher efficiency.

1 tbl

FIELD: oil extractive industry.

SUBSTANCE: method includes pumping, in carrying liquid - waterless mixture of oil products containing waterless oil, of powder-like water-soluble polymer and connector in amount of 0.05-0.2% for mass of carrying liquid or 30-100% for mass of power-like water-soluble polymer, as said mixture a mixture of waterless oil and light oil products processed in relation 0.1:9.9-9.9:0.1 is used, and as connector - dry aluminum sulfate, chrome sulfate, iron sulfate, magnesium sulfate, copper sulfate or their mixtures, or their alums with common formula MIMIII(SO4)

.2
12H2O, where MI-Na,K,Pb,Cs,NH4, and MIII-Al,Cr,Fe,Mn.

EFFECT: higher efficiency.

2 tbl

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes forming a screen of viscous-elastic mass in well via interaction of working liquid pumped into well in form of alkali waste of kaprolaktam production or its solution, with influx liquid. Necessary speed of transformation of viscous-elastic mass and intensiveness of filling of well adjacent area with it is adjusted by mode of pressing of working liquid into influx zone. For this purpose pressure increase is alternated with pressure decrease. Pressure is decreased for 10-50% from achieved maximum pressure. Relation of exposure time for increased pressure to decreased pressure time is taken in limits 1.1-5.0.

EFFECT: higher efficiency.

7 cl, 1 ex

FIELD: oil industry.

SUBSTANCE: compound has carbomide, urotropine and water, additionally has chlorine iron with following relation of components in percents of mass: carbomide 6.0-16, urotropine 5.0-8.0, chlorine iron 5.0-10, water the rest.

EFFECT: higher efficiency.

8 ex, 2 tbl

FIELD: oil and gas industry.

SUBSTANCE: method includes adjustment of pumping and dosing equipment on basis of amounts of components and their feeding time. Multi-component technological system is forced into well. Adjustment of pumping and dosing equipment is performed by means of frequency converters. Frequencies, set at frequency converter of forcing pump electric engine, at frequency converter of linker-feeding pump electric engine and at frequency converter of powdered polyacrylamide dosing pump electric engine are determined from mathematical formulae. Plant has drift dosage means for powdered polyacrylamide, drift dosage means for powdered components, two ejector mixers, mixing tank, forcing pump, linker tank. Electric engines of forcing pump, linker pump, first and second drift dosage devices are provided with frequency converters. First and second ejector mixers are provided with replaceable nozzles, with diameter 4.5-8.0 mm to provide for 150-250 m3/day plant productiveness.

EFFECT: higher precision.

2 cl, 2 dwg, 1 ex, 1 tbl

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