Method of multi-stage treatment of injection well bottomhole zone in terrigenous and carbonate formations

FIELD: oil and gas industry.

SUBSTANCE: method of multi-stage treatment of injection well bottomhole zone in terrigenous and carbonate formations includes hydrochloric acid treatment with acid composition of 0.5-1m3/m volume followed by pressing with aqueous solution of colloidal silicon dioxide nanoparticles or aqueous solution of surface-active substance of 2-3 m3/m volume; clay-acid treatment with clay-acid composition based on hydrochloric and hydrofluoric acids with 0.8 0.5 m3/m volume followed by pressing with aqueous solution of colloidal silicon dioxide nanoparticles or an aqueous solution of surface-active substance of 2-3 m3/m volume, treatment with hydrocarbon solvent of 0.5 m3/m volume and with clay-acid composition based on hydrochloric and hydrofluoric acids with 0.5 m3/m volume then by spraying aqueous solution of colloidal silicon dioxide nanoparticles or aqueous solution of surface-active substance of 2-3 m3/m volume. The following composition is used as acid composition, vol %: 30% hydrochloric acid 50-63; diethylene glycol 6-16; acetic acid 1-3; water-repellent agent based on amides, 1-3; corrosion inhibitor, 1.5-2; the rest is process water. The following composition is used as the clay-acid composition, vol %: 30% hydrochloric acid 48-60; hydrofluoric acid 1-4; diethylene glycol 6-16; acetic acid 1-3; water-repellent agent based on amides, 1-3; corrosion inhibitor, 1.5-2; the rest is process water. As aqueous solution of colloidal silicon dioxide nanoparticles, 1-2%- aqueous solution of colloidal silicon dioxide nanoparticles is used, containing wt %: colloidal silicon dioxide in acrylic acid, 32-40; propylene glycol monomethyl ether, 59.5-67.5; the rest is water. Aqueous solution of surface-active substance is 2-4% aqueous solution of surface-active substance containing, wt %: diethylene glycol, 1-3; hydrophobic agent based on amides, 0.5-2; the rest is process water. Solvent based on toluene fraction of straight-run gasoline or based on an aromatic hydrocarbon concentrateC10 is used a hydrocarbon solvent.

EFFECT: increased efficiency injection wells, reduced time for implementation of the method, its simplification and reduced cost.

2 cl, 7 dwg

 



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: method includes drilling of horizontal wellbore in productive stratum with cementing of casing string, lowering of perforator to the horizontal wellbore at the pipe string and performance of perforated openings in the horizontal wellbore with azimuth upward direction, lowering of the pipe string with a packer to the well, setting of the packer, pumping of breakdown agent through the pipe string and formation of hydraulic cracks in the horizontal wellbore. The horizontal wellbore in productive stratum is drilled in parallel to direction of the maximum stress in rocks. Then perforator is lowered to the horizontal wellbore at coil tubing (CT) and perforation openings are made in the horizontal wellbore in one row, then CT is pulled out from the well with perforator, the perforator is dismounted and the CT is equipped from below with an inflatable packer. CT is lowered up to the bottomhole by axial movement of CT from the mouth to the bottom to distance of 50m with speed rate of 0.5m/min and simultaneous pumping of viscous gel with density exceeding density of water in volume sufficient for filling with the following acid viscoelastic composite, wt %: gelling agent 12.0; 22% hydrochloric acid (HCl) 22.5; fresh water 65.5; in lower part of the horizontal wellbore section per 2/3 of the horizontal wellbore diameter. The inflatable parker is set, hydraulic fracturing is performed by pumping the following thickened acid composite, wt %: gelling agent 12.0; 22% hydrochloric acid (HCl) 68.0; fresh water 20.0; with further filling with gelling fluid with decomposer of perforated openings in the upper part of the horizontal wellbore section per 1/3 of the horizontal wellbore diameter. The inflatable packer releasing is made; then hydraulic fracturing is performed in the remaining part of the horizontal wellbore; to this end the above operations are repeated starting from the CT axial movement from the mouth to the bottom up to filling of the treated interval with gelling fluid with decomposer. Upon completion of interval hydraulic fracturing the well is developed by swabbing, at that viscoelastic gel is diluted at contact with stratal fluids and unblocks drained parts of the horizontal wellbore and then removed from the well.

EFFECT: increased efficiency of crack development, improved quality of hydraulic fracturing, reduced time for hydraulic fracturing.

5 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes the detection of dependence between an adsorption layer structure and the concentration of non-ionogenic surfactant. The concentration of the surfactant in an aqueous solution of the non-ionogenic surfactant is accepted on the condition of formation of an "island" adsorption layer on the surface of the rock - alternating hydrophilic sections of an oil reservoir surface and hydrophobic sections of absorbed molecules of the surfactant providing for structuring of oil drops in the flow. A well is selected for the operation. Control measurements of yield, well head and bottom hole pressures are carried out. The wells are investigated at stabilised and transient conditions. An acid-containing solution is pumped to the well bottom hole. Then the acid-containing solution is removed from the well by well flushing with oil. Then a packer device is installed into the well. Further pumping of a water-removing composition is carried out, as well as the aqueous solution of non-ionogenic surfactant, displacing fluid into the production well. The well is soaked, and then oil is uptaken via production wells.

EFFECT: increased efficiency of treatment due to the development of a structured adsorption layer of surfactants in a bed.

1 ex, 5 tbl, 6 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention relates to compositions for wells treatment for use in oil industry. Composition for well treatment containing chemical for well treatment adsorbed using water-insoluble adsorbent, where composition is produced by the well treatment chemical deposition from liquid, at that the well treatment chemical is adsorbed on the water-insoluble adsorbent, and where the well treatment chemical is deposited upon metal salt presence. Well treatment liquid containing the above mentioned composition and carrying liquid. Method of the underground reservoir or wellbore treatment including the above mentioned well treatment liquid injection in the reservoir or wellbore. Method to monitor the well treatment chemical release in the wellbore including the above composition injection in the wellbore. Invention is developed in subclaims.

EFFECT: improved efficiency of treatment in environments with high pH.

38 cl, 3 dwg, 4 ex

FIELD: oil and gas industry.

SUBSTANCE: method of filter cake removal of bottom hole area of low-permeable low-temperature terrigenous reservoir located near the permafrost rocks comprises sequential injection through the column of oil-well tubing to the bottom hole area of mudded low-permeable low-temperature terrigenous reservoir of methanol in a volume of 1-2 m3 per 1 m of perforated thickness, phosphoric acid of 5-6% concentration with technological thermal equilibrium time of not more than 0.5 hours. Then aerated dispersed aqueous solution of hydrogen peroxide of low concentration of not more than 10-15 wt % is injected in the volume of 2-3 m3 per 1 m of the perforated thickness with forcing the orthophosphoric acid in a distal part of the reservoir. Then aerated dispersed aqueous solution of hydrogen peroxide is injected and forced again in the reservoir using the gas condensate with short-term technological thermal equilibrium time of not more than 0.5-1.0 h. Then removal and taking away of the remaining part of the aerated dispersed aqueous solution of hydrogen peroxide from the reservoir and the well to the surface is carried out. Then the well is developed by feeding to the well of inert gas, such as nitrogen, worked out, and the well is brought into production. At that injection of aerated dispersed aqueous solution of hydrogen peroxide is carried out by pulsed-cyclical method with alternate pumping the aqueous solution of hydrogen peroxide and inert gas, such as nitrogen.

EFFECT: increased permeability of dried bottom hole area of the reservoir, increase in the degree of filter cake removal of the bottom hole area and increase in productivity of the wells.

3 ex

FIELD: oil and gas industry.

SUBSTANCE: method of acid treatment of bottom-hole zone of carbonate reservoir includes injection of the acid composition containing in wt %: inorganic or organic acid, or their mixture 9.0-24.0; zwitterion surface-active substance - oleinamidopropylbetaine 1.0-10.0; hydrophobically-modified polyurethane polymer 0.05-3.0; water - rest, at that the acid composition is injected by single stage or by portions with holding between injections. The acid composition can additionally contain anionic surface-active substance in amount of 0.1-3.0 wt %. The above specified acid composition is injected alternating with injection of hydrochloric acid at 12-24% concentration.

EFFECT: alignment of profile of inflow of the production wells in carbonate reservoirs with non-uniform permeability, creation of new fluid conducting channels through entire perforated thickness of the reservoir, restoration of reservoir characteristics of bottom-hole zone due to its cleaning of mud solid particles.

3 cl, 1 tbl, 16 ex, 4 dwg

FIELD: chemistry.

SUBSTANCE: method for interval acidising of a horizontal well using a carbonate reservoir, which includes lowering a pipe string into a well; pumping acid compositions into the formation through the pipe string; conducting geophysical investigations in the horizontal well before treatment; selecting and separating intervals of the horizontal well into two groups; the first group includes intervals with permeability of 40-70 mD and water cut of the extracted product of 70-80%; the second group includes intervals with permeability of 5-39 mD and water cut of the extracted product of 50-69%; lowering into the horizontal well a pipe string plugged at the bottom and fitted with two packers with a perforated connecting pipe in between; performing consecutive treatment of the intervals of the horizontal well relating to the first group by sealed cut-off of each interval with subsequent alternating pumping into each interval in three cycles a temporary blocking composition at a rate of 6-12 m3/h, the temporary blocking composition used being a water-in-oil emulsion with dynamic viscosity of 120 mPa·s at 20°C, and an acid composition at a rate of 54-66 m3/h; after treatment of the intervals of the horizontal well relating to the first group, retrieving the pipe string from the horizontal well; at the mouth of the horizontal well, the pipe string is fitted with a liquid pulsator above the perforated connecting pipe and the pipe string which is plugged at the bottom and fitted with two packers with a perforated connecting pipe in between is once more lowered into the horizontal well; treating the intervals of the horizontal well of the second group by sealed cut-off of each interval with subsequent pulsed pumping into each interval a self-deviating acid composition based on a gelling agent at a rate of 24-36 m3/h.

EFFECT: intensifying oil extraction from a horizontal well, increasing oil yield and reducing the water cut of the extracted product.

3 dwg

FIELD: oil and gas industry.

SUBSTANCE: method of acid treatment of the oil reservoir includes geophysical survey in open horizontal wellbore to determine dislocations crossed by the bore in the reservoir, i.e. cracks, fractures, cavities, run in the horizontal wellbore on pipes string the filters with variable perforation density, packers installation, acid injection in horizontal wellbore, acid flush, well washing and commissioning. At that one packer is installed upstream the opened wellbore between the casing string and pipes string, and rest packers (expansing packers) are installed at places where the bore crosses dislocations. For each dislocation packer is selected with length exceeding width of the dislocation determined according to geophysical curves by at least 10 times. In pipes string hydrochloric acid with concentration 10-20% is injected on the basis 5-30 m3 per meter of oil-saturated reservoir thickness under wellhead pressure Pwh=(0.008…0.011)·H, MPa, where H is average depth of the reservoir, m. Perforation holes of filters are made round with diameter 5-10 mm, similar along the wellbore. Density of filters perforation for each section created between the packers, and between packer and bore end is increased linearly from zero at periphery to maximum in centre, in its turn this is determined via the hydrodynamical perfection coefficient as follows: k1h1Lnl1rc+С1=k2h2Lnl2rc+С2=...=knhnLnlnrc+Сn, where C1, C2, Cn are hydrodynamical perfection coefficients of the well as per character of opening on each nth section along the horizontal wellbore; l1, l2, ln are length of nth section, m; k1, k2, kn are average permeability of nth section, m2; h1, h2, hn are average oil saturated thickness of nth section, m; rc is well radius, m.

EFFECT: increased oil recovery of the reservoir due to increased reservoir coverage by action.

2 dwg, 2 ex

FIELD: oil-and-gas industry.

SUBSTANCE: oil field development method involves working fluid pumping in through the injection wells and formation products withdrawal through the retrieving wells. The oil field is developed with the established ratio of formation products withdrawal compensation through working fluid pumping in. The borehole zone is treated with acid in the injection wells. The oil field is developed with the newly established ratio of formation products withdrawal compensation through working fluid pumping in until approach of the displacement front, changed as the result of acid treatment, to the retrieving well. Hydrofracturing is performed in the retrieving well with withdrawal compensation recovered to the initial value after recovery of formation products water content changed as a result of hydrofracturing.

EFFECT: field oil yield increase.

1 ex

FIELD: oil and gas industry.

SUBSTANCE: invention is related to the technology intended for well productivity improvement. Large-volume selective acid treatment (LVSAT) for producers in carbonate reservoirs includes the injection to the well of an acid composite band with the specific volume of 1.5-3m3 per 1 m of an oil-saturated interval and non-linear viscous deflecting fluid before and/or upon the injection of the acid composite band, at that the injection of the acid composite is carried out with an optimal flow rate and an optimal ratio of a deflecting fluid volume to the acid composite volume, which are defined by mathematic modelling of the process considering changes in the wellhead and bottomhole pressure, type of the acid composite, type of the deflecting fluid, porosity and permeability of rock; at that for the purpose of the optimal flow rate optimisation for the acid composite injection dependencies of the optimal flow rate of injection on the specific volume of reagents injection are obtained with different constants of the reaction.

EFFECT: improved efficiency of large-volume selective acid treatment (LVSAT) for carbonate reservoirs.

2 cl, 5 tbl, 1 ex, 11 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: proposed process comprises lowering of flow string in hydrofrac zone and sealing of well annulus by packer. Rock is subjected to hydrofracturing to produce cracks by forcing gasified fluid via said flow string with the fracture propping. After sealing of casing string-borehole annuity packer is used to cool bottom hole zone by nitrogen gas with temperature of minus 40 to minus 45 degrees Centigrade. Then, hydrofrac is performed by injection of the mix of hydrochloric acid and nitrogen in amount sufficient for production of hydrochloric acid foam with foam content of 57% at well bottom. Then, 220°C superheated steam is forced via said flow string to hydrofracture. Note here that volume of said steam is selected to equal or to exceed that of forced hydrochloric acid foam and that of flow string. Now, the well is operated.

EFFECT: higher efficiency of fracturing.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is referred to the oil industry and may be used for the stimulation of hydrocarbon production, in particular, of an oil or gas condensate, in wells, increase in their recovery factor due to the treatment of the bottomhole zone of this production formation penetrated by wells included into the formation development. According to the technique, wellhead sealing is performed. Then the well is shut down by the injection of a fluid blocking inflow from the productive formation. At the initial phase an excess pressure is generated in the well so that it exceeds the hydrostatic pressure of the fluid column affecting the productive formation per a preset value. The pressure in the well is increased further with the generation of pulse series of pressure increase in the mode of resonant oscillations with the preset frequency. Then the blocking fluid in the well is replaced by an operating fluid with the simultaneous generation of the pulse series of pressure increase in the well. The operating fluid is flushed to the productive formation at maintaining the pulse impact mode for the productive formation at another frequency differing from the earlier preset frequency until the pressure increases further in the productive formation at the final phase up to a preset value. Thereupon the pressure is decreased sharply in the well by pulse series with the provision of a break in integrity of a hydraulic medium in the productive formation zone. At that time intervals between the pulses in operations with the pressure increase are accepted as different from the time intervals between the pulses in operations with the pressure decrease.

EFFECT: increasing the production rate and reaching an initial value of the bottomhole zone permeability due to opening of a fracture network in the productive formation with prevailing vertical fractures, increasing mass exchange in the filtration zone and reliability of the filtration zone cleanup from products of man-made colmatation.

9 cl, 1 dwg, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to oil producing industry and intended for improvement of oil recovery of productive formations. The method of excitement of wave field on the injection well face consists in that the flat constrained flow of liquid is supplied continuously from the slot-hole nozzle to the wedge nose. Meanwhile the area of primary generation of vortex structures in the zone behind the nozzle cut edge is formed. Periodic breakdown of ring vortex structures from the nozzle cut edge, their movement with flow and impact with the wedge nose are provided. Pressure disturbances are generated at deformation and destruction of vortex structures on the wedge nose. Propagation of periodic pressure disturbances from the wedge nose extensively in the form of elastic waves and their chaotic reflection from surrounding walls is performed. The excitation by energy of multiple vortex structures due to energy of elastic oscillations achieving primary generation area is conducted. The liquid flow on the wedge nose is deflected to one of two diverging outlet channels. The flow is divided at the inlet upstream the output channel and sent partially to the lateral chamber interfaced with the nozzle edge and the output channel. In the chamber the pressure is increased due to piston effect of the supplied flow and the flow is pushed away to the opposite output channel, formed from two of its sides by the pressure difference. Periodic switching of the liquid flow direction between output channels is provided. The liquid is displaced alternately from the diverging channels into the common punched output collector. The field of elastic oscillations is excite on the injection well face. Thus the elastic waves reflected from walls of each chamber are focused on the nozzle cut edge interfaced to it.

EFFECT: improvement of efficiency of conversion of kinetic energy of the flow to oscillatory energy of the wave field.

2 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to the field of oil industry and can be used for enhanced oil recovery of the reservoir in the development of water-flooded reservoirs with viscous oil and bitumen at a late stage of development. The method comprises opening the reservoir with the ability to transfer the production well into the injection one, the reservoir processing, keeping the hole without any influence, intake of oil from the reservoir. At that a system of microwave electromagnetic generators with radiation frequency of 2.5 GHz is lowered into the injection well, connected to the slot antenna using the feeder. The length of the slot antenna is selected equal to the thickness of the aquifer of the reservoir. In the mode of injection, the water injection into the reservoir is carried out with simultaneous influence on the reservoir with microwave electromagnetic field, the radiation power is determined by the time of heating of the water injected in the downhole to the desired temperature. When filling 5-10% of the volume of the pore space of the formation, the well is maintained, the well is transferred into the production well, and the liquid intake from the production well is carried out.

EFFECT: increase of the effectiveness and economical efficiency of development of water-flooded reservoirs of high-viscosity oil, intensification of oil production in water-flooded reservoirs of high-viscosity oil by increasing the coverage with influence to the reservoir with heating in the bottomhole area of the reservoir of the production wells.

2 cl, 3 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes creation of compressive pressure drop between bottomhole zone of stratum and cavity of tubing string by fluid injection, pressure release at motion of fluid from bottomhole zone to day surface, generation of periodic pressure pulses in bottomhole zone of stratum, repetition of pressure release stages and pressure pulse generation stages; control over these stages. Pressure drop is generated by fluid injection into the well at the preset pressure created in the first receiver during injection subperiod, while pressure release up to the preset value is made at opening of control valve during pressure release subperiod through the first receiver. Pressure is controlled against wellhead pressure sensor and bottomhole zone pressure sensor. When maximum flow rate is attained for permanent fluid flow in annular space during injection subperiod, a submersible flow shutoff device is actuated. When maximum pressure is obtained during injection period at bottomhole zone of stratum, the second receiver is switched on.

EFFECT: higher efficiency and stability of the well operation.

2 cl, 3 dwg

FIELD: mining.

SUBSTANCE: according to the method acoustic, electric, mechanical and hydrodynamic compressing and pulling stresses are formed by acting by periodic short impulses by means of explosion of a calibrated conductor placed in a working interval of a well. This energy of explosion is brought to the coal seam. In the well the slot-hole perforation is created which is oriented in the directions of main stresses in the coal seam. An additional slot-hole perforation is formed in permeable rocks containing the coal seam. The direction of additional slot-hole perforation is oriented in the directions of the main stresses of the rocks containing the coal seam. It strengthens acoustic and hydrodynamic cavitation of gas bubbles emitted from coal, fractures, microfractures, pores, micropores, capillaries, microcapillaries of the coal seam. Fractures and microfractures are also formed in the permeable rocks containing the coal seam. It favors to development of mesh of abnormal microfracturing in the coal seam and additional fractures and microfractures in the permeable rocks containing the coal seam. In general all factors provide the maximum desorption and diffusion of methane.

EFFECT: increase of production of coal methane, reduction of energy consumption, improvement of safety and environmental friendliness of the process.

5 dwg

FIELD: oil and gas industry.

SUBSTANCE: well formation development device includes tubing string with a packer installed above the formation and filter blinded from bellow for the purpose of communication with the formation, a bit with a row of holes. The filter is equipped with nozzle on top, with inner cylindrical cavity. The bit is inserted from top to the nozzle from which it is supported by the spring upwards. From bellow the tip is equipped with a saddle and a ball mounted on the saddle. The packer is made as an inflated rubber element with hydraulic chamber connected by axial channel made in the nozzle with its inner cylindrical cavity. At that in initial position the row of bit holes is placed opposite inner cylindrical cavity of the nozzle and communicated to inner surface of the tubing string. At that a hollow body rigidly fixed to the tubing string from the top is installed telescopically at the bit top. The hollow body is fixed in regards to the bit in initial position by a shear tie and in operating position the bit may be moved axially in limited way in regard to the hollow body and nozzle, compression of the spring, fixation of the hollow bit in regard to the nozzle, sealed cut-off of the row of bit holes at the inner head of the nozzle. At that the tubing string above the hollow body is equipped with sucker rod pump.

EFFECT: improved quality of the operation device, improved reliability of sealing.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: device for pulse injection of liquid into a reservoir includes case, sleeve with central duct, positioned concentrically in the case, and process constriction in the form of removable bushing in the central sleeve duct. The case is installed on the sleeve on ball bearings. The sleeve features top and bottom rows of radial orifices with check valve placed between the orifices inside the sleeve and allowing for a flow upwards from below. Top and bottom rows of radial orifices are interconnected by a bypass duct between the case and the sleeve. The bypass duct features tangential vanes on the inner case surface, ensuring case rotation against the sleeve and partially overlapping and changing flow area of the bottom row of radial sleeve orifices by a ring featuring a row of through orifices. The ring is mounted outside of the sleeve opposite to the bottom row of radial sleeve orifices and is attached rigidly to the case. Removable bushing is installed in the central duct at the lower sleeve end.

EFFECT: higher reliability of operation.

3 dwg

FIELD: oil and gas industry.

SUBSTANCE: method comprises adding of dispersed flow of gas into the liquid flow and mixing of gas with liquid at the joint movement in the pipeline. Gas and liquid are supplied portionally. The obtained gas and liquid system is additionally pumped through the damping section of the pipeline with subsequent dispergating. For this purpose the dampener with the length 2-12 m is used. The flow rate of gas and liquid is set from the condition of their volume ratio 1.25-1.07. The surface-active substance is also used. The gas and liquid system is provided with the size of bubbles 7-12 microns as a cellular system with water between the neighbouring bubbles in membrane state.

EFFECT: improvement of efficiency of generation of steady structured fine gas and liquid mix in conditions of portion supply of liquid and gas.

1 ex

FIELD: mining.

SUBSTANCE: in the process of construction of horizontal well, the deviated hole is drilled through the rocks, descending of the upper casing pipe, cementing the borehole annulus behind the upper casing pipe, drilling the horizontal shaft from the upper casing pipe to the lower oil reservoir, descending of the lower casing pipe with a partial placement of the latter in the lower part of the upper casing pipe, cementing the borehole annulus behind the lower casing pipe, perforation of the horizontal shaft, descending to the upper casing pipe of flow string with a packer with mounting of the packer and the shoe of the flow string in the upper casing pipe over the lower casing pipe, and performing the hydraulic fracturing in the horizontal shaft. As a part of the upper casing pipe in the interval of the upper producing layer the well casing of increased thickness are used, where the packer is placed. During the hydraulic fracturing of the lower oil reservoir the pressure is created over the packer, which is allowed on the upper casing pipe. Then the simultaneous release of pressure above and below the packer is carried out, perforating of the upper casing pipe is carried out in the interval of the upper oil reservoir, and development of the well. The height of the cement sheath between the packer top and the lower oil reservoir is determined from the ratio: LPHFLPOP2, where PHFL is pressure of hydraulic fracturing of the layer, MPa; POP is pressure in the over-packer space in the process of hydraulic fracturing of the layer, MPa; L is the height of the cement sheath between the packer top and the lower oil reservoir, m; 2 is the reliability coefficient of the cement sheath, MPa/m.

EFFECT: elimination of flows in the hydraulic fracturing crack, crushing the production casing above the place of the packer mounting, and reduction of water cut of the excavated product.

1 dwg, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: regulated hydrodynamic wave generator in the producer includes a sucker-rod pump unit and a two-piece piston with centrators placed in the production casing under dynamic level of the oil well fluid at the shank end or at the lower part of the production tubing made as the tubing string. The two-piece piston is made as a bank of elements chocking jets of the oil well fluid in the production casing. The bank is formed of choking elements so that they may be flown around their bodies and their flow passages are narrowed for the oil well fluid. The choking elements are made with sharpened outer edges and flow-around surfaces at least from the side faced towards dynamic level of the oil well fluid with potential narrowing in width of flow passages and speeding-up of the oil well fluid jets in the area of jets breaking from the outer edges of the choking elements.

EFFECT: improved oil recovery due to intensification of filtering processes in the productive stratum and involvement into operation of non-operated or low-operated interlayers in the development element.

5 cl, 4 dwg, 2 tbl, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: in a method for the displacement of high-viscosity oil from an oil deposit in a permafrost zone including injection of a heated polymer solution through injectors, flushing of the polymer solution up to the bottomhole of the producer by brine water with the displacement of high-viscosity oil from the stratum with its further extraction and transportation through the producer hole to the surface, the hydrophobic polymer solution (HPS) is used and this HPS is obtained by gauging of water-methanol injection (WMI) with the ratio of water:methanol equal to 60:40 at the ratio of the water-soluble polymer:WMI equal to 1:1, HPS is heated up to the reservoir temperature and the ratio of its viscosity to the viscosity of lock oil is not less than 1:10 at the pressure of flushing that does not exceed the pressure of bottom water and gas cap, at that water-soluble cellulose derivatives or polyacrylamide or hydrolysed polyacrylonitrile are used as the water-soluble polymer.

EFFECT: ensuring the displacement of high-viscosity oil without the contamination of the production stratum and without thawing of permafrost rock surrounding the wells.

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