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Water and gas influx limiting method with well productivity recovery Water and gas influx limiting method with well productivity recovery includes running in of a perforator at the flow string, perforation of the production casing, isolation of water and gas influx and elimination of leak-tightness failures in the production casing by injection of isolating compound through new openings thus forming a water-shutoff screen. At that perforation of the production casing and injection of the isolating compound are carried out during one trip of the perforator. A hydromechanical perforator designed to make openings in the production casing and further injection of the isolating compound is used as a perforator. At that perforation of the production casing is made within the interval of water and gas inflows. |
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Method of productivity recovery and commissioning of non-operating oil and gas wells Method includes the conducting of repair and insulating works, "moderate" perforation of the production casing by a power drill with the working member equipped with hydromonitor channels, injection of sealing composition into the punched holes, bridge installation inside the production casing and subsequent re-perforation and development of the productive formation. Meanwhile during a single tripping of the perforator "moderate" perforation of the production casing is made in the interval below the productive formation and above the water producing formation. A simultaneous sealing of the formed holes of the interval and the bridge installation inside the production casing by means of supply of cementing composition through the perforator are performed. The perforator is backwashed when it is lifted to the productive formation, which is re-perforated and developed by the same perforator. |
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Interval isolation method of brine water influx in horizontal wells Method includes running in of a flexible coiled tubing, filling of the well with blocking fluid in the interval from the bottomhole up to the lower part of water influx closest to the bottomhole. Water-shutoff compound is injected and flushed to the producing formation with simultaneous running out of the flexible coiled tubing up to the upper part of water influx closest to the bottomhole. At that the rate of the well horizontal section should be several times more than the rate of the flexible coiled tubing movement in order to ensure even placement of water-shutoff compound in the producing formation. The well horizontal section is filled with blocking fluid up to the next water influx shutoff interval and isolation works are performed in sequence at each influx interval starting from the interval closest to the bottomhole. Upon isolation of the last water influx the well is closed under pressure for reaction of water shutoff elements and destruction of the blocking fluid. Thereafter the flexible tubing is run in up to the bottomhole and the well is washed in volume of at least 2 circulation cycles. |
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Method for shutoff of stratal water influx Invention is related to oil and gas industry, and namely to shutoff of stratal water influx in gas and gas condensate wells by means of coil tubing technique. The concept of the invention is as follows: the method lies in running in of a flexible pipe into inner cavity of gas-well production tubing up to the bottomhole and cleanout of the bottomhole from liquid and mechanical impurities, filling of the well with gas condensate, subsequent lifting of the flexible pipe up to tubing shoe, injection to the perforated interval through annular space between the flexible pipe and production tubing of the first package of hydrophobisated compound containing ethyl silicate ETC-40 with 10% concentration in gas condensate with volume of 1-2 m3 per each meter of gas net pay with its further flushing to the stratum and formation of water shutoff screen in the productive stratum thus pushing stratal water out from the bottomhole to the stratum depth radially. Then through annular space between the flexible pipe and production tubing injection of the second package of hydrophobisated compound is made containing ethyl silicate ETC-40 with 100% concentration in volume of 0.4-0.6 m3 per each meter of gas net pay with its further flushing to the stratum by gas condensate in the volume of production tubing and inner space of the well - production string below the tubing shoe. Then running in of a flexible pipe is repeated to the interval of gas-water contact, water-repellant organosilicon liquid GKZH-11N is injected through the flexible pipe in volume of 0.10-0.15 m3 per each meter of water-bearing thickness of the stratum, return washing of the well during 2 cycles with back pressure. The flexible pipe is removed from the well; the latter is withheld for reaction under pressure. |
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According to the method the well is killed, the sand plug is washed and hydraulic fracturing of the formation is made with its simultaneous setting within the whole perforation interval. Volume of the well bottomhole zone within the perforation interval is divided into two production facilities by injecting and flushing of waterproofing compound to the formation depth radially thus forming water shutoff screen. Time is withheld for hardening of the waterproofing compound. The well volume at the water shutoff screen level is divided into two production zones by setting a packer run in with the tubing string. The tubing string is equipped with a gas lift valve in the upper part of the upper facility perforation interval. The string shoe is set at the level of 1.5-2m below the lower openings in the lower facility perforation interval and water extraction is made by intrawell gaslift from the lower production facility due to gas energy from the upper production facility. |
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Group of inventions is related to downhole devices for instillation in the well bore in the underground area and methods of flow regulation in the well bore. Technical result lies in effective regulation of fluid flow. The downhole device for instillation in the well bore in the underground area contains the first fluid diode having the first inner surface limiting the first inner chamber and output of the first inner chamber, at that the first inner surface facilitates fluid swirling when it is directed to the output; and the second fluid diode having the second inner surface limiting the second inner chamber in fluid communication with the above output, moreover the second inner surface facilitates fluid swirling when the swirling fluid is received through the above output. In the method of flow regulation in the well bore in the underground area fluid is transferred through the first fluid diode and the second fluid diode through the channel between inner space of the downhole device and its outer space in the underground area. |
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Flow restriction control system for use in subsurface well Group of inventions is related to mining engineering and may be used for regulation of fluid inflow to the well. The system contains a flowing chamber through which a multicomponent fluid passes, at that this chamber contains at least one input, one output and at least one structure spirally located in regard to the output and thus facilitating helical swirling of the multicomponent fluid flow around the output. According to another version the system contains a flowing chamber with the output, at least one structure facilitating helical swirling of the multicomponent fluid flow around the output and at least one structure preventing redirection of the multicomponent fluid flow to radial trajectory passing towards the output. |
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Flow control device to be fitted in well (versions) and method to this end Invention relates to control over flow resistance in the well. Proposed device has the surface making the chamber and including lateral and opposite end surfaces. Note here that maximum distance between opposite end surfaces is smaller than maximum length of opposite end surfaces. It has first opening in one of end surfaces and second opening in said surface, isolated from first opening. Note here that lateral surface serves to swirl the flow from second opening to circulate around first opening. |
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Flow restriction control system for use in subsurface well According to the first alternative a flow resistance control system includes a cyclone through which multicomponent fluid flows and the cyclone input is coupled to the cyclone chamber with at least two channels. Flow resistance of the multicomponent fluid passing through the cyclone depends on rotational intensity of the multicomponent fluid at the cyclone input. According to the second alternative a flow resistance control system includes the first cyclone with input and the second cyclone receiving the multicomponent fluid from the first cyclone input through the input coupled to a cyclone chamber with at least two channels. Flow resistance of the multicomponent fluid passing through the second cyclone depends on rotational intensity of the multicomponent fluid at the first cyclone input. |
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Method of water influx isolation and limitation to horizontal wells Method includes pumping and flushing of the polymer solution and well shutdown for the period of polymer gelling. According to the invention geophysical survey is made in order to specify the interval of water influx. Computational experiments are made on the basis of water influx isolation and limitation mathematical model thus evaluating stability of polymer screens for different viscosity and volume of polymer solutions in oil- and water-bearing areas of the productive stratum at the limit depression and depression in service, residual water and oil resistance factors for injected polymer solutions considering type of the productive stratum as well as water cut of the produced oil and its flow rate after insulation and limitation of water influx. At that viscosity of polymer solutions are evaluated in time at temperature of the productive stratum. Then the polymer is selected with required viscosity and volume of injection ensuring stability of the screen based on the above polymer in oil-bearing area of the productive stratum. The selected polymer solution is injected in the calculated volume. |
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Operation method for wells placed in oil-water contact zone Operation method for a well placed in oil-water contact zone contains the stages at which the well is perforated in the oil-containing area of the stratum and water-containing area of the stratum; dual product extraction is arranged from the oil-containing area and water-containing area of the stratum through the above perforation with the controlled rate; at that well production rate is controlled and equipment is selected for production on the basis of the certain ratio and periodically changed physical and chemical and reservoir properties. |
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Method of decreasing oil producing well watering In compliance with this method, well is shut in to open casing and linear gate valves for pumping highly mineralised water into annular space. Casing valve is closed to release excess pressure for pumping of highly mineralised water into seam in preset amount at 7.5-10.0 MPa. Pumping is stopped to close the well and to level the pressure for uniform distribution of highly mineralised water in the seam water-flooded zone. Well is started to run it to constant duty for up to 5 days. Well is operated at seam depression of 0.5-1.5 MPa. Volume of injected highly mineralised water is defined by analytical expression. |
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Development method of water-flooded oil deposit Method involves drilling of a deposit with production wells crossing a formation consisting of a water-saturated zone separated with a non-permeable natural interlayer with an oil-saturated zone, lowering of a casing string with further formation perforation, investigation of its water-oil saturation and their deposit intervals, dimensions of non-permeable natural interlayer, creation of a screen from an insulating compound, which separates water-saturated zone of the formation from oil-saturated zone, cutting of some part of the casing string, enlarging the well shaft at that interval; filling of the enlarged interval of the well shaft with insulating compound, drilling of insulating compound after the insulating compound hardening. At arrangement of water-saturated zone below oil-saturated zone of the formation and at thickness of the non-permeable natural interlayer of more than 3 m, some part of the casing string is cut from the internal of 1.5 m below the roof of the non-permeable natural interlayer and up to the interval of 1.5 m above the bottom of the water-saturated zone of the formation. The well shaft is enlarged at each interval. A setup consisting of a shank and a hydraulic disconnector is assembled on the well head in an upward direction. The shank is made in the form of pipes with outer diameter of less than inner diameter of the casing string. A check valve is installed on the lower end of the shank with possibility of its opening or closing under action of excess pressure, and a filter is installed below it. The shank length of chosen with the size of not less than distance from the mine face up to the interval of 1.5 m below the roof of non-permeable natural interlayer. The assembled setup on the filling pipe string is lowered to the well till the lower end of the shank is borne against the mine face. A hydraulic disconnector is actuated; after that, the filling pipe string is raised to the height of 1 m and lowered; then, an insulating compound is pumped via the pipe string and the shank and the insulating compound is forced through by pumping of forcing-through liquid to the pipe string through the check valve opened under action of excess pressure and the filter of the shank to tubular annulus and brought to the shank head. The filling pipe string with the hydraulic disconnector is removed from the well and the insulating compound is left till it is cured. Microcement is used as an insulating compound. After the insulating compound is cured, drilling of the insulating compound and the check valve is performed, and drill products are removed from the shank by flushing. |
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Development method of water-flooded oil deposit Method involves drilling of a deposit with production wells crossing a formation consisting of a water-saturated zone separated with a non-permeable natural interlayer with an oil-saturated zone, lowering of a casing string with further formation perforation, investigation of its water-oil saturation and their deposit intervals, dimensions of non-permeable natural interlayer, creation of a screen from an insulating compound, which separates water-saturated zone of the formation from oil-saturated zone, cutting of some part of the casing string, enlarging the well shaft at that interval; filling of the enlarged interval of the well shaft with insulating compound, drilling of insulating compound after the insulating compound hardening. At arrangement of a water-saturated zone below the oil-saturated zone of the formation and thickness of the non-permeable natural interlayer of less than 3 m there cut is some part of the casing string from the bottom of the non-permeable natural interlayer to the roof of the oil-saturated zone of the formation, and the well shaft at that interval is enlarged. After that, a setup consisting of a cutter with teeth and holes, a shank and an attachment assembly is assembled on the well head in an upward direction. With that, the shank is made in the form of pipe with the diameter that is smaller than the casing string diameter. A check valve is installed on the lower shank end. The shank length is chosen so that it is equal to distance from the mine face to roof of the oil-saturated zone of formation plus two metres. The assembled setup is connected by means of a left-hand adapter to a filling pipe string and lowered to the casing string of the well till the cutter teeth are borne against the mine face. Cutter teeth are directed to the side opposite to rotation direction of the filling pipe string at detachment of the filling pipe string from the shank. Rotation of the filling pipe string is performed from the well head in a clockwise direction through 8-10 revolutions and detachment of the filing pipe string from the shank is performed. The filling pipe string is raised by 1.5 m; insulating compound is pumped to the filling pipe string and pumped with forcing-through liquid to the tubular annulus; brought to the shank head; the filling pipe string with the left-hand adapter and the attachment assembly is removed from the well, and the insulating compound is left till it is cured. Microcement is used as an insulating compound. After microcement is cured, drilling of the check valve is performed from the inner space of the shank and excess microcement is removed from the shank. Then, the well is brought into development as a production well for extraction of the product from the oil-saturated zone of the formation or as an injection well for pumping of liquid to the water-saturated zone of formation. |
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Method of development of flooded oil deposit Casing is sunk into well to perforate the bed. Oil and water saturation intervals and impermeable seam sizes are analysed. Casing part is cut out to expand the borehole in said interval. Fluid is injected in string for packer to define the bed specific capacity. Fluid circulation is defined by injecting fluid via casing string-borehole annulus. In case circulation exists, isolation composition is injected to produce isolation bridge inside casing string 20-30 m above perforation interval. In case circulation does not exist, isolation composition is discharged via casing string-borehole annulus to interval of perforation of oil-and water saturated bed zone to fill expanded bore expanded interval with isolation composition. After hardening of isolation composition, isolation composition is drilled to produce the shield opposite said saturated zone. Isolation quality is analysed. Bed perforation is repeated to resume its development. |
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Development method of water-flooded oil deposit Method involves drilling of a deposit with production wells crossing the formation with water-saturated and oil-saturated zones separated with a non-permeable natural interlayer, lowering of a casing string with further formation perforation, investigation of its water-oil saturation and their deposit intervals, dimensions of non-permeable natural interlayer, creation of a screen from an insulating compound, which separates water-saturated zone of the formation from oil-saturated zone, cutting of some part of the casing string, enlarging the well shaft at that interval; filling of the enlarged interval of the well shaft with insulating compound, drilling of insulating compound in the well so that the screen remains opposite to oil-saturated zone of the formation after waiting period of the insulating compound curing, perforation opposite to oil-saturated zone of the formation, and development of the well. At arrangement of non-permeable natural interlayer below oil-saturated zone of formation and thickness of non-permeable natural interlayer over 8 m at the bottom interval of non-permeable natural interlayer there installed is a blind packer, and temporary clogging of oil-saturated zone of formation is performed. Some part of the casing string is cut out to 1.0-1.5 m at height of 1.0 m above bottom of non-permeable natural interlayer, and in casing string interval at height 1.0-1.5 m below roof of non-permeable natural interlayer there made are holes across the casing string. Cementing casing string is lowered to well with through drillable packer, packer is installed in casing string opposite to non-permeable natural interlayer in interval between cut out part and holes in casing string, circulation of fresh water is induced on well head along cementing casing string under packer via casing string annulus and intertube space on well head by pumping of fresh water. If there is no fresh water circulation, impulse treatment of non-permeable natural interlayer by mud acid composition is performed. When circulation is available pumping of fresh water is stopped, then insulating compound is pumped via grout casing string and is forced into casing string annulus in interval of non-permeable natural interlayer with formation of insulating bridge in inner space of casing string to the bottom of oil-saturated zone of the formation. Then grout casing string is lifted above the bottom of oil-saturated zone of the formation and surpluses of synthetic resin are washed out from intertube space of casing string. After some period required for synthetic resin curing through and blind packers are drilled as well as insulating bridge, temporary clogging of formation is removed and well is brought into operation. |
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Development method of water-flooded oil deposit Method involves drilling of a deposit with production wells crossing the formation with water-saturated and oil-saturated zones separated with a non-permeable natural interlayer, lowering of a casing string with further formation perforation, investigation of its water-oil saturation and their deposit intervals, dimensions of non-permeable natural interlayer, creation of a screen from an insulating compound, which separates water-saturated zone of the formation from oil-saturated zone, cutting of some part of the casing string, enlarging the well shaft at that interval; filling of the enlarged interval of the well shaft with insulating compound, drilling of insulating compound in the well so that the screen remains opposites oil-saturated zone of the formation after waiting period of the insulating compound hardening, perforation opposite oil-saturated zone of the formation, and development of the well. At arrangement of water-saturated zone below oil-saturated zone of the formation and thickness of non-permeable natural interlayer of 0.5 to 4 m at the bottom interval of non-permeable natural interlayer there installed is a blind packer; some part of the casing string is cut out from the blind packer to the roof of the formation oil-saturated zone; the well shaft is expanded at the interval of the cutout part; the expanded well shaft interval is filled with insulating compound. Microcement is used as the above insulating compound so that an insulating bridge is obtained. After waiting period of microcement hardening, the insulating bridge and the blind packer are drilled so that the screen remains opposite non-permeable natural interlayer and oil-saturated zone of the formation with the diameter equal to inner diameter of the casing string; water-saturated formation zone is cutout by placing in the casing string below the cut-out part of a stationary packer with a perforated shank with a limit stop on the working face from below and a sealing joint from above. After that, the cut-out section of the casing string is fixed in the well by lowering an additional string with its installation opposite the cut-out section of the casing string and tight fixation of upper and lower ends of the additional string in the casing string above and below the cut-out section in the well. When oil-saturated zone of the formation is being introduced to the development, drilling perforation of an additional string is performed opposite oil-saturated zone of the formation. During development of water-flooded oil deposit, periodic operation of oil-saturated and water-saturated formation zones is performed. |
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Isolation method of brine water influx in well According to the proposed method, after a tubing string is removed from the well to the interval of flooded part of productive formation, a sand plug is inwashed. Above it at the interval of the non-flooded part of productive formation there installed is an insulating cement bridge from hydrophobisating cement composition. After completion of waiting-on-cement period (WOC), it is drilled and a cement ring is left on walls of the production string. The sand plug is removed below the cement ring in flooded part of the productive formation. An insulating packer lowered on a string of process pipes is installed on the roof of productive formation. At the interval of the flushed sand plug there pumped under pressure through existing perforation holes of flooded part of productive formation or through newly created process openings for waterproofing is waterproofing composition; waterproofing composition is reinforced with a reinforcement cement bridge from cement mortar based on cement of normal density, which is installed on the well shaft. After the reinforcement cement bridge is installed, the insulating packer is unpacked, and the string of process pipes is lifted. After wait-on-cement time (WOC) is over and strength and leakage test of cement bridge is completed, the pipe string with the packer is removed from the well, repeated perforation of the non-flooded part of productive formation covered with cement ring is performed in the most effective gas-saturated part of the section. Acid treatment of newly developed perforation interval is performed to destruct the cement ring; a new tubing string is lowered to the well and the well is developed. After stable influx of gas is obtained from the formation to the well there pumped and forced through to the bottom-hole zone of the formation is mixture of methanol with non-ionogenic surface-active substance to remove water component of the filtrate of hydrophobisating cement compound, the well flaring is performed till the well reaches the working mode and then it is put into operation. |
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Method to isolate inflow of reservoir water in low-angle and horizontal wells Method provides for isolation of an inflow of reservoir water in low-angle and horizontal wells, equipped in productive formations with a tail filter separated into sections with solid and filter sections with packers installed on each segment of solid sections and connected with a lift string, the diameter of which is more or equal to the diameter of the tail filter. According to the invention, as water level increases in the productive formation, serially, without well plugging, a perforation charge is lowered on a flexible pipe via a stuffing box into the tail filter. Perforation holes are created under the packer in the zone of inflow of reservoir water. The flexible pipe is extracted. Then a packer plug is lowered on it with circulation holes. The pipe space is sealed over the zone of reservoir water inflow in the segment of the solid section, and a process fluid is injected for absorption into a waterlogged section of the bed under the packer plug for displacement of the reservoir water. This zone is filled with a tamping fluid. Afterwards the flexible pipe is disconnected from the packet plug, lifted above the packer plug to close circulation holes and extracted from the well. After dismantling of the stuffing box the well is put in service with operation of the bed above the packer plug. |
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Method for limiting water influx in production well Method involves descending of hydraulic jet perforator at specified depth, descending of tubing string with packer into the well, pumping of fracturing fluid and sand-carrier with restraining material into tubing string, process exposure, well putting into operation. According to invention the data of geological-geophysical researches help to determine the character of formation saturation and position of gas-water contact. Hydraulic jet perforator is descended at 5-10 m below gas-water contact. There performed is a hydraulic fracturing of the formation in interval opened by hydraulic jet perforator. Water saturated part of the formation is developed via tubing string and gas saturated part of the formation - via annular space. The restraint of water influx into the well is adjusted by water withdrawal through tubing string. |
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Isolation method of brine water influx in well Isolation method of brine water influx in the well flooded with brine water cone, at which isolating cement bridge from hydrophobisating cement compound is installed after removal of tubing string from well at perforation of non-flooded part of productive formation. After waiting on cement period is completed, it is drilled so that cement ring remains on walls of production string, which covers the perforation interval of non-flooded part of productive formation. To interval of flooded part of productive formation there pumped under pressure through lower perforation holes is water isolating composition, for example plasticised cement grouting or gel with increased flowability and permeability so that make-up cement bridge from cement solution on the basis of cement of normal density remains in well shaft, which covers lower perforation holes made in flooded part of productive formation. After wait-on-cement time (WOC) is over and strength and leakage test of cement bridge is completed, repeated perforation of the perforation interval of non-flooded part of productive formation covered with cement ring is performed in the most effective gas-saturated part of the section. Methanol is pumped through newly formed perforation holes to remove aqueous component of filtrate of hydrophobisating cement compound; then, acid treatment of newly opened perforation interval is performed to destruct cement ring, tubing string is lowered to the well to the depth of upper holes of new perforation interval and the well is developed. |
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Isolation method of brine water influx in well Isolation method of brine water influx in the well flooded with bottom formation waters with rise of water-gas contact (WGC) above lower holes of perforation interval, at which cement bridge from hydrophobisating cement compound is installed after the well killing and removal from it of tubing string at interval from working face to upper perforation holes. After the waiting period of cement curing ends, it is drilled in non-flooded part of productive formation and below current WGC by 3-5 m so that cement ring remains on walls of production string. In wall of production string, at interval of 2-3 m above and 2-3 m below current WGC there made are process openings, through which waterproof composition, for example plasticised cement solution or gel with increased flowability and penetrating capacity, is pumped to the formation depth. Make-up cement bridge from cement grouting on the basis of cement of normal density, which covers the process openings, is installed in well shaft at interval of 3-4 m above and 3-5 m below current WGC. After waiting on cement there partially drilled is make-up cement bridge at the distance of 2-3 m above current WGC. Repeated perforation of the current perforation interval covered with cement ring is performed at the most effective gas-saturated part of cross section, with formation of new perforation interval. Methanol is pumped through newly formed perforation openings; then, acid treatment of newly opened perforation interval is performed. Production tubing is lowered into the well to the depth of upper holes of new perforation interval and the well is developed. |
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Method control over oil deposit development Invention relates to control over oil deposit development and may be used for increasing reservoir recovery or in reservoirs developed by heat methods. Method of developing deposit with different-permeability beds and high seam temperature of 90°C and higher, or in subjecting the bed to 100-320°C, comprises injecting, portion-by-portion, the water solution of aluminium and carbamide salt. Note here that, first, injected is portion of water solution containing in wt %: aluminium salt 1.0-3.0, carbamide 3.75-15.0 wt % and water making the rest, to make sol in the bed, and, then, one more portion of water solution containing in wt %: aluminium salt 3.5-17.0, carbamide 16.0-30 and water making the rest to make gel in the bed. Aluminium salts represent anhydrous or hydrated aluminium chloride or nitrate, or their partially hydrolysed elements. Note that aluminium hydroxochloride aluminium oxide 10-30 wt %. |
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Method of producing oil in porous fractured reservoirs reducing well product water content Proposed method comprises injecting displacement agent via injection wells and oil extraction via production well to water influx into well products making operation inefficient, injecting water-shutoff agent containing water-swellable particles with initial size smaller than flooded fracture follow section, conserving the well for composition structurisation period, developing and commissioning the wells. Grit from rubber-based elastomer resulted from crushing rubber 'AQUASTOP' channel or polymer grit resulted from crushing sealing gasket 'PLUG' are fed into fluid to be injected into production and injection wells, grit initial grain size being smaller than flooded fracture flow section but exceeding than of pores of oil-saturated block of bed. Said grit swells in water by, at least, 300% in 24 hours to concentration of 3-40 wt % in working fluid based on water thickened by polymer and bearing viscosity killer to release injection water. Said fluid is forced into bed by sweet water. |
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Method of recovery of flooded gas well with collapsed production tubing in productive interval In compliance with proposed method, top section of production tubing is cut and extracted. Permanent cement plug is fitted in well flooded parent hole. Opening is cut above said plug in parent hole production tubing and extra hole is drilled not extending beyond parent hole of flooded well bottom zone to arrange shoe 2-3 mm above gas-water contact (GWC). Said extra hole is cased by casing liner and cemented. Said liner is perforated some 5-7 m above GWC to produce water-shutoff holes. Water-shutoff agent if injected via said holes to displace water down into bed to make water-shutoff shield. Water-shutoff composition forced through process holes for water-shutoff is made up by plasticised oil-well cement composition with increased penetrating capacity. Water-shutoff cement bridging from oil-well normal-density cement is arranged in liner to cover aforesaid process holes. After cement curing and testing cement bridging for strength and tightness, liner is perforated at productive bed top section to develop the well. |
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Oil deposit development method According to the method working agent is pumped through injection wells, oil is extracted through production wells and insulation works are performed in production wells. According to invention, in order to perform water-insulation works there chosen are production wells in which watering-out of extracted products has increased with current water-oil of less than 8, with fluid rate of not less than 10 m3/day, water-intake rate of not less than 100 m3/day at mined oil-saturated thickness of productive layer of not less than 3 m and at stable operating mode of not less than 1.5 months. Besides, injection wells shall have influence coefficient of not less than 0.4 and be in stable operation for at least 1.5 months. Polymer systems hardened in formation conditions so that polymer gels are created are chosen as material for waterproof works. |
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In method for balancing of injection well water-intake capacity profile and restriction of water influx to production wells, which involves pumping to the formation of gel-forming composition containing, wt %: sodium silicate 1-10, chrome acetate 0.5-2, water is the rest, pumping of the above composition to formation, technological pause, prior to pumping of the above composition to wells there pumped is fresh water; induction period of gel-forming composition at formation temperature is set so that it is equal to 6-10 hours, and technological pause is chosen so that its duration is equal to 24-36 hours. |
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Formation permeability control method In formation permeability control method involving subsequent pumping to the well through separating bank of fresh water or oil, liquid wastes of produced zeolites and gel formation initiator, forcing-through of pumped reagents to formation with waste water or oil, the solution of by-product of produced polyethylenepolyamines - reagent of ammonium chloride is used as gel formation initiator. |
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Method for horizontal well operation According to the method, a well is operated until water intrusion of production. A pipe string is lowered into a horizontal part of the well, and the annular space is filled with a cement mortar, the cement mortar is squeezed into a borehole environment via the pipe string, and squeezing is stopped, when pressures in the pipe string and the annular space are balanced, the process exposure is carried out for cement setting and hardening, the pipe string is cleaned from cement remains. The process exposure is carried out for at least 3 months with periodical research of the borehole environment with a pulse neutron generator. The process exposure is stopped after readings of the pulse neutron generator are stabilised. Using the readings of the pulse neutron generator, oil zones of a horizontal bore are identified. Oil zones are perforated from the remote end of the horizontal bore to the wellhead. Oil is withdrawn until water intrusion into a zone, the watered zone is isolated, and oil withdrawal continues. |
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Polymers swelling in water preventing loss of circulation Here is disclosed procedure for treatment of borehole of well entering underground reservoir. The procedure consists in placement of composition of sealant with polymer containing reverse emulsion in borehole of the well to prevent absorption of working substance in the underground reservoir during its placement in the borehole. According to the procedure polymer containing reverse emulsion is dehydrated to content of 10% of water before its placement in the borehole of the well. Composition of sealant for realisation of this procedure includes polymer containing reverse emulsion. The latter includes particles with dimension in the range from approximately 0.01 micron to approximately 30 microns. Also, polymer containing reverse emulsion is produced with its dehydration to content of 10% of water. The invention is developed in dependent clauses of the patent claim. |
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Procedure for development of multi-pay oil deposit Procedure for development of multi-pay oil deposit consists in casing string opening, in lowering packer on oil-well tubing (OWT), in positioning packer between reservoirs, in pumping hardening back-filling solution and in its conditioning. Back-filling solution is preliminary pumped and pressurised into a lower watered reservoir. Upon back-filling solution hardening in the reservoir the casing string is opened above the lower reservoir. Packer is set above interval of casing string perforation. A connecting rod receiving fluid from the watered reservoir by means of the pump is arranged at a lower end of the OWT string. |
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Procedure for development of water-flooded oil deposits Procedure consists in drilling-out with producers crossing impermeable natural inter-layers in pay-out bed, in lowering casing string with successive perforation of pay-out bed, in analysis of oil-and-water saturation and intervals of their bedding, in analysis of dimension of impermeable natural interlayer and in making barriers out of insulating composition separating water-saturated zones of bed from oil-saturated zones. By results of analysis there is determined thickness of the oil-saturated zone of the bed. If thickness of oil-saturated zone of the bed exceeds 4 metres, part of the casing string is cut out in the interval above lower perforation orifices of the oil-saturated zone of the bed up to a bottomhole of the well. Borehole is enlarged in this interval and is filled with isolating composition corresponding to cement grout. When thickness of the oil-saturated zone of the bed is below 4 metres, then a part of casing string is cut out from the roof of the impermeable natural interlayer to the bottomhole of the well. The borehole of the well is enlarged in this interval and is filled with isolating composition. There is formed a packer by introduction into the bottomhole zone of the oil-saturated zone of the well bed. |
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Sand plug is washed down to lower perforation holes of existing interval of perforation, and buckling of flow string is eliminated. Then tail of smaller diametre pipes is lowered in inner cavity of flow string to head of washed sand plug, with arrangement of tail head by 20 m higher than reservoir roof, which is cemented by mortar, leaving cement sleeve in inner cavity of tail down to depth of upper holes of existing perforation interval. After cement hardening, tail and flow string are perforated in interval of above dehydrated part of reservoir to its roof. Lifting string is lowered into well, gas inflow is caused from reservoir, and well is flared, gas dynamics research is carried out, and well is put in operation. At the same time cement mortar consists of portland cement, superplasticiser C-3, polyvinyl alcohol and polypropylene fibre. |
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Sand plug is washed down to lower perforation holes of existing interval of perforation, and buckling of flow string is eliminated. Then water-insulation composition is injected into existing interval of perforation, is pushed into reservoir, creating a water-insulation screen, and displacing reservoir water in depth of reservoir by displacement fluid. Then tail of smaller diametre pipes is lowered in inner cavity of flow string to head of washed sand plug, with arrangement of tail head by 20 m higher than reservoir roof, which is cemented by mortar, leaving cement sleeve in inner cavity of tail down to depth of 1-2 m higher than current gas-water contact and higher than upper holes of existing perforation interval. As cement hardening waiting time elapses, two strings, tail and operating strings are perforated for operation, in interval above the cement sleeve to roof of reservoir. Then lifting string is lowered in well by 1-2 m higher than the tail head. Gas flow is caused from reservoir, and well is flared. Gas dynamics research is carried out, and the well is commissioned. At the same time water-insulation composition is represented by liquid glass, displacement fluid - by methanol, cement mortar is a composition that consists of portland cement, superplasticiser C-3, polyvinyl alcohol and polypropylene fibre. |
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In well operation method involving pumping of composite material to the formation to the interval below oil-water contact, process exposure and operation of the well, there preliminarily performed is forcing of water from inter-tube space with oil to the interval below oil-water contact; in order to prepare composite material the thickener is filled to inter-tube space of the well on the basis of 1-5 kg per 1 m3 of oil located in inter-tube space, and mixing of thickener with oil in inter-tube space by oil circulation with thickener via tubing string and inter-tube space, and pumping of solution of oil and thickener from inter-tube space to the interval below oil-water contact is performed in pulse mode under pressure exceeding hydrostatic one by not more than 10%; at that after process exposure the well operation is performed during the first 5-15 days in moderate mode with flow rate of not more than 50% of the operating one. |
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Method of supply of hydrocarbons from watering out formation Method involves use of the well and flow column lowered to it, pumping to productive formation of liquid or liquid-gas mixture prepared by using the mixing device the discharge of which is interconnected with flow column, and low and high pressure chambers - with gas and/or liquid sources. According to invention, the pumping of liquid or liquid-gas mixture is performed periodically to the watered-out interval of productive formation. On bottom hole of the well, in annular space between flow column and casing string in the interval above and within the limits of the watered-out part of productive formation there installed are not less than two packers. Annular space in the packer installation interval is filled with non-newtonian fluid. Two circulation valves are installed in flow column. One is installed in watered-out interval of the formation, and the other one - above the upper packer. |
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Creation method of low-premeability of screen in porous medium It is implemented preparation of injection well in insulated area by path close to roof cladding configuration of insulated area of stratum. Then it is pumped into it solution of foam maker with following feeding of gas for foaming. It is defined minimal horizontal lateral dimension of screen from conditions of filtration through the screen of gas and/ or water considering pressure gradient at the boundaries of screen at the period equal to period maximal pumping into gas storage or maximal permissible withdrawal of gas from particular storage. Minimal vertical dimension if screen is considered equal to value which is not less than maximal dimension from roof of formation up to gas-water contact in the area of screen creation. In preference it is implemented injection well making, path of which is normal to vector of average speed of formation fluid in isolated area of stratum. Preferentially it is also implemented making of inclined and/or horizontal injection well. |
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Composition for oil recovery rate increase and its producing method Invention relate to oil exploration industry and can be used for formation water in-flow limitation. Composition producing method includes mixing of a water solution with carbon black, at that preliminary disperse carbon black in the methyl cellulose diluted water solution, at component ratio wt % : carbon black 15.0, methyl cellulose 0.05, the rest is water. Then mix received concentrated suspension with methyl cellulose water solution and carbamide at the following component ratio wt %: methyl cellulose 0.5-2.0, carbamide 2.0-20.0, carbon black 0.5-5.0, the rest is water. The composition of oil recovery rate increase characterised with the mentioned above method. |
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Water inflow into well limitation method Invention related to oil-and-gas industry and can be used for water inflow into well limitation methods. According to the method execute high viscosity oil and cement heated mixture pumping via thermal insulated pipes, driving with low viscous oil and process ageing. According to the invention kill the well with well killing fluid, execute works until well specific intake capacity value is equal 0.5-3.0 m3/(h·MPa), pump into the well not less then 8 m3, with density equal well killing fluid density. Execute pumping though thermal insulated pumps of the high viscosity oil and cement heated mixture with consumption rate 2-10 m3/hour. |
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Method of efficiency recovery and stand by wells, with collector of complicated design in abnormally low formation pressure conditions and production string bottom part collapse includes execution of repair-isolation works and reservoir opening. Sweep up the string, repair its compressed bottom, wash in a sand plug till depth of the nearest to a gas-water contact - GWC clay sub layer, descend in to the string a tail from casing pipes of a smaller diametre up to the sand plug head, with the tail head dislocation 20 m above of the reservoir roof, cement the tail with a cement slurry, leaving a cement barrel 1-2 m higher the tails shoe. After cement fixing - CFT drill the cement barrel, wash the sand plug up to the current GWC, through perforation holes with perforation interval 15-20 m3 of the water sealing composition, press it through 3-5 m3 of the cement slurry in to the reservoir, creating water sealing screen and stop over the defined height cement barrels sand plug. After the CFT execute perforation - hydro-sand-jetted or with powerful cumulative perforator - of the production string and the tail in interval over cement barrel head up to the reservoir roof and gas flow activation. The cement slurry contains portlandcement, superplastisiser C-3, polyvinyl alcohol, and polypropylene fiber. |
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Method of oil recovery increase in watered reservoirs Invention related to oil-and-gas production, particularly to production efficiency increase. The method includes pumping into reservoir, through injection wells system, into zones around wells tall oil with filler - dispor in amount 5-10% of the tall oil and continue watering. |
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Method for insulation of bottom water influx in gas wells Invention is related to gas production industry, in particular to methods for isolation of bottom water influx in gas wells. In method for isolation of bottom water influx in gas wells, including lowering of oil well tubing (OWT), pumping of blocking polymer compound with previously identified value of structural viscosity in annular space, cement isolating substance along OWT, their pushing through with process fluid, lowering of OWT is done down water entry bed, additionally prior to pumping of blocking polymer compound, a low-viscous gel-forming compound is supplied into annular space, which contains the following components, wt %: sodium silicate of "Sialit 30-50" grade 50, liquid waste from process of electrochemical metal coating 0.8, water - the rest, adding the latter to water entry bed, and blocking polymer compound is added to gas-bearing bed, then they are pushed through by pumping of process fluid along OWT with annular space closed, blocking polymer compound is used with a value of structural viscosity that exceeds at least thrice value of structural viscosity of low-viscous gel-forming compound, for headers with high permeability they use polymer compound as blocking polymer compound with organic filler, containing the following components, wt %: lignosulphonate 5, calcium chloride 15, gas condensate 20, peat-alkaline filler 7, technical water - the rest, and for headers with low permeability - polymer compound with condensed solid phase, which contains the following components, wt %: calcium chloride 9, twice-substituted ammonium phosphate 11, water-soluble polymer 2, surfactant 1, technical water - the rest, at the same time volume of blocking compound is defined according to given calculation formula, and pumping of cement isolation compound along OWT is done in volume that exceeds volume of operational pipe in interval of water entry bed by 20%, at the same time pushing of cement isolation compound is started to be done with annular space open, and after it reaches bottom of gas bearing bed, it is pushed with annular space closed with pressure that exceeds pressure of absorption. |
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Method of recovery of yield and bringing to operation of temporarily shut-in wells with complicated structure of collectors under conditions of abnormally low bed pressure including repair, insulating, and exposure of producing bed consists in following: initially, sand plug is washed for depth 2-3 m below current gas-water contact (GWC); producing string is callipered, shank end out of casing tubes of smaller diametre is lowered into producing string up to head of washed sand plug; head of shank end is arranged 20 m above top of producing bed. The shank end is cemented with cement grout; upon waiting-on-cement completion (WCC) two columns, the producing column and the shank end are perforated in interval below the first over current GWC clay interlayer to depth 2-3 m below current GWC. Water insulating composition at volume 15-20 m3 is pumped through perforated openings made for water insulation; composition is forced through into depth of the producing bed creating a water insulating screen with cement grout of volume 3-5 m3; a cement sleeve 1-2 m above the first over the current GWC clay interlayer is left at the bottomhole. Upon WCC perforating is performed for operation of two columns, the producing column and the shank end in interval above the second over the current GWC clay interlayer up to the top of the producing bed; gas discharge is initiated. Composition containing Portland cement, super-plasticiser C-3, polyvinyl alcohol and polypropylene fibre is used as cement grout; while for perforation either a high-power cumulative perforator or hydraulic jet are used. |
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Method of processing oil-field strata Invention relates to the oil industry, particularly to methods of processing strata of oil-fields, and can also be used for waterproofing oil wells and for regulating intake profile of intake wells. The method of processing oil-field strata involves pumping a composition into the strata, containing aqueous solution of an anionic polymer, water soluble inorganic or organic acid or a mixture of acids, aliphatic or aromatic alcohol or a product containing it, and a polyvalent metal salt. The said composition also contains a surface-active substance or a mixture of surface-active substances, fine-grained hydrophobic material FGHM and an inhibitor. Before adding polyvalent metal salt to the aqueous solution of anionic polymer, the said alcohol or product containing it, surface-active substance or mixture of surface-active substances, FGHM and inhibitor are added and pH of the reaction mixture is brought to 0.5-3.0 by adding the said acid or mixture of acids with the following content of components, wt %: water soluble anionic polymer 0.004-5.0, alcohol or product containing it 0.50-50.0, surface-active substance or mixture of surface-active substances 0.50-10.0, FGHM 0.1-3.0, polyvalent metal salt 0.003-0.30, inhibitor 0.1-3.0, water - the rest. The invention is developed in a subclaim. |
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Procedure for selective isolation and restraint of water production into horizontal wells Invention refers to oil producing industry, particularly, to procedures of isolation and restraint of water production in horizontal boreholes of producing wells. The procedure consists in polymer pumping, in driving polymer solution, and in well shut-down for the period of polymer structure formation. Prior to pumping polymer solution into each interval, blocking fluid with optimal period of "life" is pumped into the well; further, specified volume of polymer is pumped into an isolated interval during this period of "life"; after the expiration of the period blocking fluid self-decomposes in volume required for filling the horizontal borehole from the bottomhole of the well to the nearest from the bottomhole boundary of interval of polymer solution treatment. Upon conditioning, decomposer of polymer is pumped into the well for the period of polymer structure formation in the latest treated interval; with water decomposer is further driven through into a reservoir to the nearest near-well zone and is conditioned there for the period of polymer decomposition. |
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Executing mechanism and method of implementation of this mechanism For actuation of said executing mechanism it is provided osmotic element. The osmotic element is placed into flow of fluid medium owing to which there is provided an effort and motion required for actuating executing mechanism on account of using the difference of values of osmotic pressure either between solution inside the osmotic element and external flow of fluid medium or in a layer containing this fluid medium relative to the said element. It results in corresponding displacement or adjustment of the valve, or regulating device, limiting inflow. |
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Method of restriction of bottom water and annulus overflows in production wells Invention refers to methods of restriction of bottom water and annulus overflows in production wells. The method consists in pumping water and solution of sodium naphthenate into a well; then the procedure is repeated not less, than 3 times; also cement solution is pumped with addition of sodium naphthenate; while initially solution of sodium naphthenate and water is pumped and then additionally alumo-chloride is pumped. Volume ratio of sodium naphthenate and alumo-chloride can be 4:1. |
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Method of increasing oil production and reduction of water cutting of production Invention relates to methods of increasing oil production and reducing water cutting of production. According to the method water with initial ionic force of 0.0004-0.0008 mole/l is activated in a cathode zone of diaphragm electrolytic cell chamber during 0.5-3 hrs at imposition onto water of electric field of E=(1000-15000) V/m strength. Powder of silica sand, or glauconite, or a rank of alumina silicates: zeolite or amphoteric materials: bentonite, montmorillonite, nontronite, kaoline (anauxite), talk, pyrophyllite, each separately or in random mixture are introduced into activated water at weight ratio to water 5-25%. Produced dispersive mixture is passed through the cathode zone of the electrolytic cell at strength of electric field E=(1000-15000) V/m at a rate of 1-10 m3/hour during one hour, thus obtaining activated dispersive system which further is pumped into horizon in volume of 5-100 m3. After that fresh water is pumped into the horizon as a buffer at volume of 1-20 and 3-80 m3 of horizon water as driving under pressure of 60-90 atm at during 3-5 hours. |
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Method of dry operation of wells Invention relates to oil and gas production industry, namely to dry operation of wells. The substance of the invention is as follows: according to this method wells are equipped with flow and production strings and includes injection of water repellent compound under pressure into the seam. According the invention prior to mining operations a flexible pipe is lowered into the internal space of the production string under pressure by means of the coil tubing rig. The circular and annular spaces of the well are opened. The water repellent compound is injected through the flexible pipe in the amount required, overpressure being maintained in the circular and annular spaces, which exceeds the pressure of the water repellent compound injected by not less than 10%. The water repellent compound is forced through into the seam up to the depth required. Next the flexible pipe is withdrawn out of the well. The water repellent compound is injected regularly during the period of increased gas extraction out of wells without killing the same. |
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Method for non-uniform oil reservoir development Method involves injecting isolation composition namely Portland cement dispersion and water-soluble polymer in well, wherein the components are taken in proportion of 1:(0.01-0.5) in oil-bitumen product, 5-56 parts by weight of Portland cement and water-soluble polymer are taken for 100 parts by volume of said dispersion; injecting aqueous Portland cement solution along with said dispersion, wherein the solution is taken in proportion of (0.1-0.5) per 1 part of said dispersion. |
Another patent 2542209.