Recovery method for oil-source reservoirs by the controlled multi-stage hydraulic fracture

FIELD: oil and gas industry.

SUBSTANCE: invention can be applied in the development of oil-source reservoirs managed using a controlled multi-stage hydraulic fracturing (MHF). To isolate high permeability zones and fractures, the method comprises applying in the wells of injection of mixture of surfactants, polyacrylamide (PAA), a stapler - chromium acetate, filler and water, well subjecting to process exposure, products selection from wells. According to the invention, a low-permeability reservoir is selected with an average absolute permeability of less than 2 mD, which are used for drilling, or already drilled horizontal sidetrack wells are used. In each of such wells, the first MHF is performed, during which the fracture propagation area is recorded by means of low-frequency seismic survey. Packers separate the horizontal wellbores into sections, then the wells with conducted MHF are injected, through each horizontal wellbore section, with insulating composition with the following component ratio, wt %: SAW - 0.2-5.0, PAA - 0.005-2.5, chromium acetate - 0.01-1.0, filler - 0.5-15.0, water with a salinity of less than 1.5 g/l - the rest. After the soak period during 1-10 days and colmatation of fractures after the first HF, the second HF is conducted in the same wells by the pumped insulation compound, during which fracture propagation is also recorded by means of the low-frequency seismic survey. Upon obtaining data on fractures distribution after the first and the second MHF, a decision is made on performance in these injection wells of subsequent phases of insulating composition injection and MHF conducting. Moreover, the number of subsequent MHF is determined based on the full reservoir coverage with MHF fracture zones both in plan and in profile around each horizontal wellbore. After all MHF, the reservoir is processed by separate injection in each stage of the horizontal wellbores of the insulating composition solvent in a volume of 0.8-2.0 from the total volumes previously pumped insulating compositions to this satge of the horizontal wellbore.

EFFECT: increasing of the coverage factor and oil production of the oil-source reservoirs.

 



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: coupling comprises a housing with inner trapezoidal grooves, a movable element in the form of a pipe with a mating protrusion of trapezoidal shape on the outer surface and a seat for placement of the ball inside, a port for hydraulic fracturing, a ball activating the movable element, a hollow piston with holes and a supporting spring mounted in the cavity under the piston. The movable element is made without a hole and is provided with two protrusions of trapezoidal shape on the outer surface and one seat. The seat is located between the protrusions of trapezoidal shape.

EFFECT: increase in reliability of fixing of the movable element in the housing of the device, and improvement of quality of processing of the borehole due to improvement of the system of opening ports.

2 cl, 3 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: chemistry.

SUBSTANCE: invention relates to liquids for the hydraulic fracturing of subterranean formations in oil and gas extraction. The method of applying liquid for hydraulic fracturing in the formation of fracturing of subterranean formations includes the retardation of polymer splitting in the liquid for hydraulic fracturing at a temperature from 125 to 400F, when the liquid for hydraulic fracturing contains a liquefier, by the combination of at least one radical acceptor with the liquid for hydraulic fracturing. The mixture for the application in the liquid for hydraulic fracturing contains a radical acceptor and a liquefier. The method of the hydraulic fracturing of subterranean formation includes the supply of the liquid for hydraulic fracturing, containing a propping means, a polymer and the liquefier, addition of the radical acceptor, supply of the liquid to a desired location in a subterranean formation to form at least one hydraulic fracturing, making it possible for the liquefier to split the polymer and reduce the viscosity of the liquid for hydraulic fracturing at a specified time or at a specified temperature. The invention is developed in dependent claims.

EFFECT: increase of viscosity control efficiency.

15 cl, 1 dwg, 1 ex

FIELD: oil-and-gas industry.

SUBSTANCE: group of inventions relates to methods of preparation and treatment for well stimulation. The method of preparation of branch holes includes drilling of multiple branch holes from a vertical well. A selective injection deflector with pass-through for tubing between each respective pair of branch holes is installed. Hydraulic fracturing of multiple branch holes within one completion run by means of consecutive isolation of branch holes from multiple branch holes and supply of hydraulic fracturing fluid medium to each consistently isolated branch hole during lowering are performed.

EFFECT: improvement of efficiency of hydraulic fracturing of branch holes without lifting of equipment.

9 cl, 37 dwg

FIELD: mining.

SUBSTANCE: device comprises a housing with a channel, elastic sealing elements mounted therein on it, between which a piston pair with the sealing rings is placed, and the retaining nut. The working chamber of the piston pair is connected with the housing channel, and in its cylinder a radial hole is made with the ability of communication with the working chamber of the piston pair when packing the well with elastic sealing elements and the additional compression of the elastic sealing elements when hydraulic fracturing pressure with self- locking of the isolated part of the well. The elastic sealing elements are made of soft material and reinforced with rigid elements with different elastic properties.

EFFECT: increase in the sealing capacity of the device and the elastic properties of the elastic sealing elements.

2 dwg

FIELD: mining.

SUBSTANCE: method comprises a test injection of fracturing fluid and a pack of fracturing fluid with proppant, correction of the fracturing project and carrying out the main fracturing process. At that in the high-permeability reservoirs having an absolute permeability of not less than 100 mD, the main process of hydraulic fracturing is carried out using standard working fluid flow rate of 2.2 m3/min to 4.0 m3/min. When pressing the proppant-gel mixture the stepwise reduction of flow rate is carried out with the reduction step in the range of 0.1 m3/min to 0.5 m3/min, but to the value of not less than 2.0 m3/min. The final concentration of proppant is set of not less than 800 kg/m3.

EFFECT: increase in efficiency of intensification of operation of the well by creating a wider and conducting crack in the bottom-hole area of the layer.

1 tbl

FIELD: oil and gas industry.

SUBSTANCE: method includes bottom hole back filling, test pumping of a breakdown agent and a pack of the breakdown agent with a proppant, correction of the breakdown project and completion of the primary breakdown process. For backfilling of the bottom hole they use proppant waste of hydraulic rupture completion. The waste is delivered to the bottom hole in portions by means of a sludge pump.

EFFECT: reduction of material consumption for hydraulic rupture.

1 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: method includes uptake of oil via production wells, pumping of a working fluid via injection wells, hydraulic fracture of a bed in the injection and production wells. A pool area is identified with the low bed pressure and the injection well with low injection capacity. Hydraulic fracture is carried out in the identified injection well. Development is carried out to increase the bed and bottom hole pressure in reacting production wells. Hydraulic fracturing is carried out in the production wells in series from a well with the lowest increase of the bed and bottom hole pressure to a well with the highest increase of the bed and bottom hole pressure. At the same time in the wells with a reservoir with high permeability they carry out a sparing hydraulic fracture, and in the wells with the low permeable clayey reservoir they carry out intense hydraulic fracture with the maximum length of the crack.

EFFECT: increased efficiency of the bed hydraulic fracture.

FIELD: oil and gas industry.

SUBSTANCE: method involves landing of tubing string with packer to a well, packer seating, hydraulic fracture liquid injection by the tubing string with packer to a low-permeable formation, hydraulic fracturing of the low-permeability formation with further fracture fixation by injection of liquid carrier with propping agent via the tubing string, pressure relief in the well. Before tubing string landing to the well, water-bearing interlayer interval of the low-permeable formation is perforated to form perforation holes. Then at the wellhead the tubing string is filled upwards from the bottom with a plug, lower hole rows, packer, upper hole rows and additional packer. Inside the tubing string, a mobile bushing with radial channels is inserted to seal lower hole rows of the tubing string tightly in initial position and connecting the tubing string via upper hole rows and perforation holes to the ware-bearing interlayer. A seat is installed inside the mobile bushing, the mobile bushing and the seat are fixated in initial position against the tubing string by a differential shear element. The tubing string is landed to the well, packer and additional packer are seated in the well so as to shot water-bearing interlayer off tightly at two sides, upper water0bearing interlayer is isolated by injection and flushing of water isolation composition via the tubing string through upper hole rows to the water-bearing interlayer through perforation holes under pressure twice lower than hydraulic fracture pressure of the formation, process break is made for solidification of the water isolation composition, then a ball is dropped to the tubing string from wellhead, and overpressure is formed in the tubing string. First the shear element is destroyed, and under impact of overpressure above the ball, mobile bushing is shifted down along the tubing string to a stop against the tubing string plug, overpressure increase in the tubing string is continued, and the shear element is destroyed again. The seat is brought down to a stop against the plug under impact of overpressure above the ball. Upper hole rows of the tubing string are shut off tightly by the mobile bushing, and lower hole rows are connected to the tubing string by radial channels of the mobile bushing.

EFFECT: improved efficiency of hydraulic fracturing.

2 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: invention mainly relates to methods of hydrocarbons production from hydrocarbons containing reservoirs. Method of treatment of the reservoir containing crude oil including stages when: (a) composition is supplied to extract the hydrocarbons to at least part of the reservoir, at that the composition contains at least two internal olefin sulphonates selected from group comprising internal C15-18-olefin sulphonates, internal C19-23-olefin sulphonates, internal C20-24-olefin sulphonates and internal C24-28-olefin sulphonates, and at least one viscosity decreasing compound, that is isobutyl alcohol, ethoxylated C2-C12-alhohol, 2-butoxyethyl, butyl ether of diethylene glycol or their mixture, and (b) composition is provided with possibility to react with the reservoir hydrocarbons. Invention also relates to method of viscosity decreasing of composition of highly active surface-active substance and composition for hydrocarbons extraction.

EFFECT: result is creation of more effective method of hydrocarbons extraction from crude oil containing reservoir.

14 cl, 2 dwg, 2 tbl, 2 ex

FIELD: oil and gas industry.

SUBSTANCE: method involves hydrophobisation of pore space in bottom-hole zone rock with 0.5-25% solution of polymethylhydridosiloxane in organic liquid containing its polymerisation catalyst. The solution is pushed down into the reservoir by gaseous agent selected out of nitrogen, natural gas, exhaust gases of combustion engines. Gaseous agent is fed to the well at a pressure exceeding reservoir pressure at least by 1.0 MPa. After the solution is pushed down, the well is left for process aging for two days.

EFFECT: reduced water saturation of reservoir bottom-hole zone, enhanced gas well deliverability with single treatment of reservoir.

3 tbl

FIELD: oil and gas industry.

SUBSTANCE: method includes vibration impact on the oil reservoir by the resilient oscillation sources. For this on ground surface near the wellhead of the production well the oscillation sources of same frequency are installed. Near the external boundary of the specified well the oscillation sources of same but higher frequency are also installed. Simultaneous impact of oscillations from all sources on the oil reservoir is performed with intensity, time of impact and oscillations interference ensuring coagulation of oil drops in porous space of the oil reservoir with water and directed flow movement due to difference of frequencies of the oscillation sources towards wellhead of the production well. At that contracting effect of the directed flow movement towards the wellhead of the production well is specified by number of sources of the resilient oscillations in the external boundary of the production well.

EFFECT: increased oil extraction due to reduced filtration resistances during water-oil emulsion movement via the porous environment.

2 dwg, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to secondary methods of HC extraction from the underground reservoirs, in particular to methods of the hydraulic fracturing without the proppant, as well as to the selective injection to some underground reservoirs. As per the method the selective stratum of stratums set is isolated along the well bore in the underground section from rest stratums of the set. The selective injection is used to supply fluid to the selective stratum in the stratums set. At that the fluid is supplied to the selective stratum regardless of the fact weather the fluid was supplied to the neighbouring stratum of the stratums set. Isolation means isolation of the stratums set from pressure acting on the selective stratum when the fluid is supplied to the selective stratum. Hydraulic fracturing of each stratum of the stratums set is performed. Testing of the stepwise pressure variation is performed for at least one stratum of the stratums set. Testing of the stepwise pressure variation includes opening of one of the reservoir stratums in the stratums set by the fluid injection to the well bore. At that one of the stratums is opened at specified pressure. The fluid backflow is ensured such that one of the reservoir stratums is closed. Re-opening of the one of the reservoir stratums is performed for one or more times. At that the reservoir opening pressure is reduced each time. Mode is determined when the reservoir opening pressure is below the injection pressure at which the reservoir injection ensures the fluid supply to the stratums set. As response to determination that the reservoir re-opening pressure is below the injection pressure the test is completed by stepwise pressure variation.

EFFECT: increased efficiency of HC production.

21 cl, 7 dwg

FIELD: oil and gas industry.

SUBSTANCE: according to the method capital mining operations are carried out on penetration and developing access channels to a productive formation of a deposit. Underground mining and development operations and field operations on the well production of shale oil and gas are performed using multistaged hydraulic fracturing or thermal effect on the formation. A shale oil- and gas-containing deposit is penetrated by vertical shafts. Preparation of the productive formation for hydrocarbon production is carried out by the underground mining and development openings placed below a water-bearing horizon covering the rock above the shale rock of the deposit. Hydrocarbon production is carried out by mining blocks of underground producing wells with horizontal sections protruded in the formation. The producing wells are drilled from underground cells constructed mainly in the mining and development openings. Before complete hydraulic fracturing of the formation small diagnostic hydraulic fracturing of the formation is made in the producing wells of a small diameter, which are drilled mainly from the mining and development openings to the whole thickness of the productive formation transversely to its course. The product of the producing wells is divided in the shaft bottom into shale gas and shale oil. The shale oil is outputted to the surface for further treatment before delivery to consumers. The shale gas is burnt in the boiler of a shaft bottom heat-generating plant to generate water steam or hot water used for the production of electricity or for the purpose of a thermal effect on the productive formation in order to increase intensity and the production rate.

EFFECT: reduced total volume of operations on drilling producing wells while developing shale deposits.

2 cl, 11 dwg

FIELD: oil and gas industry.

SUBSTANCE: method involves the use of horizontal holes, the horizontal section of which passes through the oil formation at the minimum distance from the gas cap 1/2 thickness of the oil part. The branch with sealing of annular space directed upwards is formed, with crossing of gas-oil contact and opening of gas saturated part of the formation. Meanwhile the string is perforated with opening of the gas cap in two opposite sections of the well within the target formation. Control of flows of gaseous and liquid fluids in the well between various perforation intervals is performed using the bypasses adjustable from the surface. The well design according to the method allows to perform independent gas recovery in required volumes from two intervals of gas cap opening, that allows independently to monitor the movement of the gas-oil contact and lift the formation fluid to the surface at the expense of natural gas-lift.

EFFECT: increase of level of development of oil stocks by means of control of intraformational cross-flows of gaseous fluid and minimizing of risks of coning, decrease of expenses for lifting of formation fluids to the surface at the expense of natural gas-lift.

6 cl

FIELD: oil and gas industry.

SUBSTANCE: according to the method intervals of a well are completed opposite the gas-saturated part, so called gas cap, and oil-saturated part of a productive stratum. A tubing string is run in to the well. The gas cap is isolated by a packer. Gas is injected to the gas-saturated part of the productive stratum and the product is extracted by a borehole pump. Simulated completion opposite the gas-saturated part of the productive stratum is ensured by the creation of drainage channels oriented radially inward the stratum. Then two coaxially mounted tubing strings of a different diameter are run in to the well. The tubing string with a lesser diameter is run in to the level of the oil-saturated part of the stratum and equipped with the borehole pump connected by an exhaust line to the ground separator intended for the separation of associated gas. The tubing string with a bigger diameter is run in to the level of the gas-saturated part of the stratum and connected to a pressure line of the separated associated gas from the ground gas compressor. Oil is extracted through the tubing string of a lesser diameter. Injection of the separated gas is made through the tubing string of a bigger diameter. At that the separated gas under pressure is delivered to a space between packers in the gas-saturated part of the stratum over gas-oil contact (GOC) thus supporting energy of the stratum at a permanent level. As far as to oil extraction from the oil-saturated part of the stratum and injection of the separated gas to the gas-saturated part of the stratum, GOC boundary is shifted stage by stage as per the thickness of the stratum from its roof to the bottom thus ensuring the gradual oil draw-down rate.

EFFECT: reduced labour costs at implementing associated gas injection to oil wells in order to maintain the reservoir pressure during operation of hydrocarbon deposits and improvement of their productivity.

1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: drilling of new wells or selection of drilled wells is executed. Several pumps are lowered in the well. Note here that in terrigenous or carbonate bed oil afflux to every productive well horizontal hole is predefined. Horizontal boreholes that differ in oil yield by 20% and more are selected. Pumps are lowered on parallel strings in horizontal borehole in length smaller than 300 m. Pumps are lowered on parallel strings in horizontal borehole in length over 300 m. Spacing between pumps does no 30 m. Every horizontal borehole is arbitrarily divided into three sequential sections. Pumps with output 2-10 times higher than that of pumps in section at horizontal borehole end are lowered at the central section.

EFFECT: accelerated oil extraction, uniform development, higher bed oil yield.

2 cl, 1 dwg

FIELD: oil extractive industry.

SUBSTANCE: method includes electro-hydraulic treatment of bed at resonance frequency and extraction of oil from bed. According to invention bed is excited by resilient pulses at broad frequency range from 0 to 10 kHz. Frequencies are set, at which bed is treated. Resonance frequency is kept by singular, periodical, radially focused electro-hydraulic pulses with generation frequency, divisible by bed resonance frequency. Concurrently in adjacent well bed excitation frequency is controlled by resilient pulses and corrected according to measurements results.

EFFECT: higher efficiency.

2 dwg

Up!