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Bottomhole zone treatment method for horizontal well Bottomhole zone treatment method for a horizontal well includes running-in into the treated bottomhole zone of a hydroperforator with a one-way acting pipe string with nozzles faced upwards, impact of hydrocarbon solvent jet through it, then impact by acid solution, process withhold for reaction with acid, running-out of the equipment from the well, swabbing and bringing the well into production. Before running-in, at the head of a horizontal well, the lower end of the pipe string is equipped bottom upwards with a centralising tube, the one-way acting hydroperforator with nozzles faced upwards, a pulsed liquid pulsator, a valve consisting of a saddle and body with openings covered tightly by the saddle fixed by a shear pin in regards to the body, the pipe string is run in into the bottomhole of a horizontal well until it backs the centralising tube. Then in pulse mode, in two stages, the bottomhole zone is impacted through the hydroperforator at first by a hydrocarbon solution jet, then by a jet of hydrochloric acid. While implementing two stages with simultaneous injection of hydrocarbon solvent or hydrochloric acid the pipe string is moved from the bottomhole to the head at constant speed along the length of the horizontal well screen. When injection of hydrochloric acid is completed the hydroperforator is placed at the well screen end from the well head side, then a plug is set at the head to the pipe string and flushed by process liquid through the pipes till it sets at the valve saddle and the shear pin is destroyed under pressure in the pipe string. Then the process is withhold during 1 hour, at that in process of this withhold the pipe string is run in until the hydroperforator rests in the bottomhole of a horizontal well. Then, during three cycles, 0.5 m3 of process liquid is injected to the pipe string and tubing-casing annulus in turn. When withhold time is over reaction products are washed out by return circulation in one and a halve volume of the well. |
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Treatment method of bottomhole zone Method includes running-in of a pipe string into the bed perforation interval, flushing of the well equipped with the master and casing valves, treatment of the bottomhole zone by injection of a hydrochloric acid solution through the pipe string and a process holdup for reaction. According to the invention the pipe string is equipped by an impulse pulsator from below and by a valve above the impulse pulsator. The pipe string is run in into the well so that the lower end of the pipe string is located opposite the bed perforation interval, fresh water with addition of a surface active compound (SAC) is injected into the bed in a pulsed mode closing the casing valve under pressure that does not exceed permitted pressure to production casing with further spill and recovery of direct circulation. Then the valve is actuated and the impulse pulsator is cut off, the pipe string is run in additionally so that radial openings of the valve are located opposite the bed perforation interval. The hydrochloric acid solution is pumped through the pipe string until it reaches the bed perforation interval, a hydrochloric bath is set and the well is held. During the process holdup fresh water with SAC addition is injected each half an hour in sequence to the pipe string and a tubular annulus. After the holdup completion the reaction products are flushed from the well. An actual bed intake is determined by injection of fresh water with SAC to the bed through the tubing-casing annulus under pressure that does not exceed the permitted pressure to the production casing. If the actual bed intake is bigger or equal to the optimal intake then treatment of the bottomhole zone is stopped and the pipe string is run out from the well. If the actual bed intake is less than the optimal intake then at the open master and casing valves return circulation of the fluid is induced and the well is flushed. At that the master valve is closed periodically till the bottomhole pressure increases per 4 MPa from the initial value with further opening of the master valve till a transparent fluid appears. At that permitted pressure for production string is not exceeded. Return circulation is continued within 1 hour and then the actual bed intake is determined again. |
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Procedure for treatment of bottomhole zone of reservoir of oil well Invention refers to oil industry, namely to methods for treatment of a bottomhole formation zone of an oil well with acid compositions. Method for treatment of a bottomhole formation zone of oil well involves pumping of acid water solution under pressure over 5 MPa into formation with further process conditioning. As acid water solution, 0.5-1% water solution of agent with phosphonic acids is used. The specified solution is pumped in during 7-10 days under pressure up to 8 MPa in volume of up to 2 m3 per 1 m of penetrated net thickness, or in case of pumping in of 2 m3 per 1 m of penetrated net thickness before 7 days, during the remaining time until process conditioning the specified solution is flushed into formation by process fluid under pressure of 5-8 MPa with further process conditioning during 7-10 days. In case if less than 0.5 m3 per 1 m of penetrated net thickness is pumped in during 10 days, process conditioning is carried out by maintaining pressure in a well of 5-8 MPa. |
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Simulated completion method for gas well productive formations Flow sting with a re-entry guide is run in up to the perforated interval. Through the flow string to the perforated interval one or several shape-charge perforators are run in at the logging cable, depending on the interval size, the perforators are equipped with a connected container filled with a chemical compound, for example, with foam compound or gas- and foam generating composition. At first the container is actuated by breaking the protective shell. The chemical compound reduces density of the solution inside the perforated interval of the well, in result depression is formed (Par>Pbth). The perforators are ejected. When in result of perforation communication with the formation appears, the foamed liquid (aerated mixture), remains of the drill mud are lifted to the surface by the gas flow. |
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Treatment method of bottom-hole formation zone In the method for treatment of bottom-hole formation zone space above and below the perforation interval is straddled, solvent for asphalt, resin and paraffin deposits (ARPD) is injected into the straddled space, acidic agent - aqueous solution of acid - and displacing fluid is injected with maximum flow rate at pressure not more than 5 MPa, the process is withhold so that components could react and well is developed by swabbing. A mix of solvents MIS-prom, ITPS-RS and process water are used as ARPD solvent with the component ration of (0.34-0.38):(0.03-0.05):(0.57-0.63), polyamide acid salts are used as acidic reagent and oil is displacing fluid. |
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Treatment method of bottomhole zone Invention relates to oil industry. Treatment method of bottomhole zone includes running tubing string to the interval of stratum perforation, pulsed pumping of 10-15% water solution of hydrochloric acid through the tubing string, process holdout within 3 hours for the purpose of reacting and extracting of reaction products. Before running the tubing string is equipped bottom-up with device for pulsed fluid pumping, breakable valve, tube with perforated holes and sleeve inside and packer. In running process tube with perforated holes is installed 2 meters below the lower interval of stratum perforation. Hydrocarbon solvent is pumped through the tubing string in continuous mode with unseated packer; then process holdout is maintained. In process holdout process fluid is pumped in volume of 0.5 m3 to the tubing string and annular space alternately in 4 cycles each 20 minutes; thereafter hydrocarbon solution and reaction products are washed by backwash from the well. Then the tubing string is elevated so that the device for pulsed fluid pumping is set opposite bottom of the stratum; the packer is seated, sleeve is moved down relative to the tube with perforated holes, and holes of the perforated tube are sealed by sleeve fixing in regard to the tube with perforated holes; the tubing string is filled with process fluid and by created excessive pressure the breakable valve is cut thus allowing fluid communication in the piping string and stratum through the device for pulse fluid pumping. Then through the tubing string pumping ad squeezing of 10-15% water solution of hydrochloric acid is made in pulsed mode in volume based on calculation of 0.8 m3 per 1 m of stratum thickness with gradual flow rise of 10-15% water solution of hydrochloric acid pumping from 0.5 m3/h up to 0.8 m3/h; process holdout is maintained within 3 hours and reaction products are extracted by swabbing. |
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Carbonate formation hydraulic fracturing method In a carbonate formation hydraulic fracturing method involving perforation of well walls at the required interval of the well with channels with depth of not less than length of a stress concentration zone in rocks from the well shaft, lowering to the well of the tubing string with a packer, sealing of the tubular annulus with the packer above the perforation interval, performance of hydraulic formation fracturing by stage pumping to the well of gel-like fracturing liquid and acid, hydraulic fracturing of carbonate formation is performed in series at several stages; with that, at the fist stage, gel-like fracturing liquid is pumped in the volume of at least 6 m3; at the second stage, gel-like fracturing liquid mixed with a propping agent is pumped. As the propping agent, metallic spheres with particle size of 12/18, or 16/20, or 20/40 mesh, which are made from magnesium metal, are used. The propping agent is pumped in portions with subsequent increase in its concentration mixed with gel-like fracturing liquid; at the third stage, forcing-through liquid - service water is pumped in the volume equal to inner volume of the tubing string lowered to the well; at the fourth stage, chlorhydric acid is pumped in the volume of at least 0.6-0.7 of total volume of gel-like fracturing liquid; at the fifth stage, forcing-through liquid - service water is pumped in the volume equal to the volume of the tubing string lowered to the well plus 0.2 m3. |
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Method of submerged reservoirs processing Method of processing for dissolution of acid-soluble material and solubilisation of hydrocarbons, emulsions and water barriers comprises the following jobs. Injection of micellar dispersion in the bed, said dispersion is a Winsor micro emulsion IV containing water, one or several precursors of organic acids, one or several surfactants and, not necessarily, one or several substances selected from salts, auxiliary surfactants and/or organic fluids which are not precursors of organic acids. Solubilisation is performed of micellar dispersion of hydrocarbons, emulsions or water barriers present in the bed and in-situ hydrolysis of, at least, a portion of organic acid precursor to produce sufficient amount of organic acid to cause notable dissolution of acid-soluble material present in filtration crests or nearby them, or other damage in the bed. Hydrolysis of organic acid precursor brings about the production of at least one of formic, acetic, hydroxiacetic and lactic acids. Organic acid precursor concentration makes at least 1 wt %. Well shutdown after introduction of micellar dispersion makes 0.5 h or more. |
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Development method of bottom-hole zone Invention relates to oil industry. Method of bottom-hole zone treatment includes running-in of pipe string with packer to perforated interval, washing of the well equipped with master and casing valves, packer seating above the formation and treatment of the well by pumping of hydrochloric acid solution through the pipe string in pulsed mode, process exposure for reaction and extraction of reaction products. Optimal intake of the formation is set before treatment of bottom-hole zone. Then the pipe string at the well mouth below packer is equipped with impulse liquid pulsator, at that a valve is mounted between the packer and liquid pulsator. The pipe string is run-in into the well so that packer is located above the formation, thereafter with open master and casing valves the well is flushed by straight ring circulation during 10-20 minutes. The casing valve is closed and process liquid is pumped into the formation under pressure that does not exceed permitted pressure to the production string during 5-10 minutes. The casing valve is closed and process liquid is drained from the well. Washing and drainage of process liquid is repeated 3-5 times. Then hydrocarbon solvent is pumped to the pipe string, the packer is seated, hydrocarbon solvent is pressed into the formation by process fluid under pressure not exceeding permitted pressure to the formation; the well is subjected to process exposure. When process exposure is completed the valve is actuated, liquid pulsator is cut off, the packer is released, the pipe string is run-in additionally so that radial openings of the valve are located opposite the formation; and then the well is washed out by process liquid at open master and casing valves by straight ring circulation during 2 hours. At that casing valve is closed partially periodically till bottom hole pressure increases per 3-5 MPa in comparison with the initial pressure value transparent liquid appears; at that permitted pressure for production string is not exceeded. Thereafter hydrochloride acid solution and acid-clay cut mud heated up to temperature of 40-50°C is pumped to the pipe string, the packer is seated, hydrochloride acid solution and acid-clay cut mud are pressed to the formation by process liquid under pressure that does not exceed permitted pressure on formation, the packer is released and the well remains under exposure, then by return ring circulation reaction products are washed out till transparent liquid appears, hereupon actual intake of the formation is defined. |
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Development method of bottom-hole zone Invention relates to oil industry. Method of bottom-hole zone treatment includes running-in of pipe string with packer to perforated interval, washing of the well, packer seating in production casing with master and casing valves above the formation and pumping of hydrochloric acid solution through the pipe string in pulsed mode, process exposure for reaction and extraction of reaction products. Optimal intake of the formation is set before treatment of bottom-hole zone. At the well mouth the pipe string below packer is equipped with impulse liquid pulsator, at that a valve is mounted between the packer and liquid pulsator; pipe string is run-in into the well so that packer is located above the formation; thereafter the well is flushed with process liquid at open master and casing valves by straight ring circulation in pulse mode during 10-20 minutes. The casing valve is closed and process liquid is pumped into the formation under pressure that does not exceed permitted pressure to the production string during 5-10 minutes. The casing valve is closed and process liquid is drained from the well. Washing and drainage of process liquid is repeated 3-5 times. Then actual intake of the formation is determined at pressure that does exceed permitted pressure to the production string. If actual intake is lower than the optimal one then hydrochloride acid bath is installed in the well opposite formation interval under pressure that does not exceed permitted pressure to the production string. If actual intake is equal to the optimal one or higher then hydrocarbon solvent is pumped to the pipe string, add process liquid up to volume bigger per 0.5-1 m3 than volume of the reagent displaced from the pipe string under pressure not exceeding permitted pressure to the formation. The well is subjected to process exposure. When exposure is completed the valve is actuated, liquid pulsator is cut off, the packer is released, the pipe string is run-in additionally so that radial openings of the valve are located opposite the formation; by return ring circulation reaction products are washed out during 3-5 hours, at that fluid influx from the formation is controlled. Then casing valve is closed and by process liquid pumping to the pipe string through the valve well intake is determined under intake pressure of the formation. |
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Invention relates to oil industry and may be used for treatment in wellbottom zone. Method of formation treatment includes running-in of pipe string with packer to perforated interval. The well equipped with master and casing valves is flushed. Packer is seated above the stratum, thereafter the well is treated by acid solution pumping through the pipe string in pulsed mode. Before treatment the optimal intake is set for formation. Then the pipe string at the well mouth below packer is equipped with impulse liquid pulsator. At that a valve is mounted between the packer and liquid pulsator. The pipe string is run-in into the well so that packer is located above the formation; thereafter the well is flushed with process liquid at open master and casing valves by straight ring circulation during 1 hour. Then process liquid circulation is continued; periodically casing valve is closed until bottomhole pressure increases per 3-5 MPa in comparison with initial pressure with subsequent opening of the casing valve till transparent liquid appears. At that permitted pressure for production string is not exceeded. Thereafter ring circulation is continued within half an hour. Then hydrocarbon solvent is pumped to the pipe string, the packer is seated, hydrocarbon solvent is pressed into the formation by process fluid under pressure not exceeding permitted pressure to the formation. The packer is released and the well remains under exposure. Then acid-clay cut mud heated up to temperature of 40-50°C is pumped to the pipe string, the packer is seated, acid-clay cut mud is pressed to the formation by process fluid under pressure that does not exceed permitted pressure on formation. The packer is released and the well remains under exposure. After exposure period the valve is actuated and impulse liquid pulsator is cutoff. Then the packer is released, the pipe string is run-in so that radial openings of the valve are located opposite the formation and by reverse ring circulation reaction products are washed out during 1 hour. Thereafter the master valve is closed and process fluid is pumped to the formation though annulus and actual intake value is determined for the formation. |
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Acid treatment method of bottom-hole zone of well in carbonate formation In an acid treatment method of bottom-hole zone of a well in a carbonate formation, which involves pumping of acid solution to the well, forcing-through of acid solution with forcing-through fluid, exposure of the well for reaction of acid solution and well development, prior to pumping of acid solution to the well there determined is porosity and permeability of a productive formation, as well as productive formation temperature. After that, volume pumping rate of acid solution and forcing-through fluid is calculated as per the following formula: q = q 0 ⋅ e 25.8 − 7550 T K m 10 ⋅ h , , where q - volume pumping rate of axis solution and forcing-through liquid to the well, m3/s; h - productive formation thickness, m; T - productive formation temperature, K; K - productive formation permeability, mcm2; m - productive formation porosity, unit fractions; q0 - empirical coefficient equal to 0.05 to 0.20. Acid solution and forcing-through liquid with calculated volume rate is pumped. Acid solution pumping is performed under pressure on the working face below natural mircocrack opening pressure. |
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Treatment method of bottom-hole oil formation zone In treatment method of bottom-hole zone of an oil formation, which involves series pumping of hydrocarbon solution of the product based on non-ionogenic surface active substance and acid-containing reagent, as hydrocarbon solution of the product based on non-ionogenic surface active substance there used is hydrocarbon solution of emulsifier of inverted emulsion of hydrocarbon solution of a mixture of non-ionogenic surface active substances, or hydrocarbon solution of a mixture of non-ionogenic surface active substances with anionic surface active substances, which is forced through with water to the formation; exposure is performed during 1-24 hours; after that, acid-containing reagent is pumped and forced-through with water to the formation. |
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Method of efficiency and control estimation for carbonate formation acid treatment Method of efficiency and control estimation for carbonate formation acid treatment involves core sampling and preparation of core samples. Chemical agent is pumped through core samples. Polished specimens are taken from the side of chemical agent input and output. At that before chemical agent pumping through prepared core samples the samples are surveyed at scanning electron microscope. After chemical agent pumping core samples are tested by CT-scanner. Images are compared and the most effective forms of solution channels are detected. Thereafter efficiency of acid treatment is estimated by calculating impact factor by computer processing of images; at minimum impact coefficient summary is made about the biggest efficiency of acid treatment. |
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Device for treatment of bottom-hole formation zone of oil well Device for treatment of a bottom-hole formation zone of an oil well includes an air chamber with atmospheric pressure and a receiving chamber made from light-weight elasto-plastic material. In the receiving chamber a provision is made for composite materials of cylindrical shape: slightly gassy material and material that generates gas at combustion, and in addition, the receiving chamber of the device includes composite material that generates gas and acid at combustion between slightly gassy and gas-generating composite materials. Slightly gassy composite material at combustion, which faces the air chamber and is fixed with radially located metal pins relative to the receiving chamber housing, is made of composition containing the following, wt %: agranulated ammonium nitrate grade B 45-46, potassium bichromate 1-2, epoxy resin grade ED-20 40-42, plasticising agent grade EDOS 2-3, hardening agent Agidol grade AF-2M 9-10. Gas- and acid-generating composite material at combustion is made of composition containing the following, wt %: ammonium nitrate 40-50, powder-like fluorine rubber grade SKF-32 with dispersity of 0.5-1.5 mm 10, chlorinated paraffin wax grade KhP-1100 10-30, and fluoroplastic grade F-32L 10-40. Composite material that generates gad at combustion is made of composition containing the following, wt %: ammonia nitrate 78-85, powder-like nitryl butadiene rubber with dispersity of 0.5-1.5 mm 12, and potassium bichromate 3-10. |
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Treatment method of bore-hole zone Treatment method of a bore-hole zone involves the first stage, at which solution of surface-active substance (SAS) 0.5-1.5% in formation water in the volume of 100-200 m3 is pumped to the well; the second stage, at which there pumped is water solution of hydrochloric acid (10-15%) in the volume based on 0.25-0.5 m3 per running metre of perforated depth of the formation at initial pressure equal to final pressure at the previous stage; the third stage. At which there pumped is water solution of hydrochloric acid (10-15%) with a retarder of the reaction of acid with rock in the volume of 2-5% of volume of the acid solution in the pumping volume of 1-1.5 m3 per running metre of the perforated formation depth at initial pressure equal to final pressure at the previous stage; formation water forcing-through in the volume of 100-200 m3 at initial pressure equal to final pressure of pumping at the previous stage; process exposure during 16-48 hours and bringing the well into operation. Formation water can be pumped in advance to the well till pumping pressure rise at the well head to 1-2 MPa. |
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Treatment method of bottom-hole formation zone Acid treatment method of a bottom-hole formation zone involves pumping to the formation of emulsion and water solution of an acid; at that, first, water solution of acid is pumped, and pumping of water solution of acid and emulsion is performed in a series-and-alternating mode, and emulsion containing the following components, wt %, is used as emulsion: acid 5.0-40.0; emulsifier - anionic or nonionic, or cationic surface-active substance, or their mixture 1.0-10.0; hydrocarbon solvent 5.0-40.0; decomposer - primary or secondary alcohol or their mixture 0.1-5.0; corrosion inhibitor 0.01-0.05 and water is the rest. Emulsion can contain viscosity regulator in the quantity of 0.01-6.0 wt %. Water solution of acid with concentration of 3.0-24.0% is used. |
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Treatment method of bottom-hole formation zone In a treatment method of a bottom-hole formation zone, which involves pumping to the formation of acid-oil emulsion of reverse type and acid, as acid-oil emulsion of reverse type there used is emulsion containing the following components, wt %: dispersion medium - hydrocarbon liquid 31-38, emulsifier - reaction products of aliphatic amines of fat acids of hydrated tall oil with hydrochloric acid in terms of amines 0.02-0.08, dispersion medium - synthetic, inhibited hydrochloric acid (10-18%) is the rest. |
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Method for near well-bore treatment with acid Method for near well-bore treatment with acid involves at the first stage pumping into the well of 10-15% aqueous solution of hydrogen chloride in a volume calculated on the basis of 0.25-0.5 m3 per 1 running metre of penetrated stratum depth; at the second stage - pumping of 10-15% aqueous solution of hydrogen chloride with a retarder of the acid reaction with rock in the volume of 2-5% of acid solution volume in total volume of pumping calculated on the basis of 1-1.5 m3 per 1 running metre of penetrated stratum depth at initial pressure equal to the final pressure value during pumping at the previous stage; overflushing by oil in volume of 5-15 m3 at initial pressure equal to the final pressure value during pumping at the previous stage; soaking during 16-48 hours and input of the well into operation. |
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Procedure for treatment of bottomhole zone of producer with two wellheads In procedure for treatment of bottomhole zone with two wellheads in case of failure of an electric-centrifugal pump (ECP) with no apparent deviation in its operating parameters and in case of alkalinity growth for extracted product up to pH>7 the required volume of hydrogen chloride solution is calculated on the basis of a length and diameter of the well filtering part; the required volume of hydrogen chloride solution is selected to treat the whole volume of the strainer; the required volume of flush fluid is calculated for delivery of compounds into a slope wellhead. ECP is shutdown at the vertical wellhead before pumping of hydrogen chloride solution is started. The required volume of hydrogen chloride solution is carried out into tubular annulus from the side of the vertical wellhead. When pumping of hydrogen chloride solution is over extraction from the slope wellhead is increased and ECP is started from the vertical wellhead. ECP is stopped at the vertical wellhead and hydrogen chloride solution is overflushed by the flush fluid into filtering part of the well. After ECP startup in enlarged extraction rate from the slope wellhead samples are taken periodically in order to check pH value, monitor dynamics in changes of fluid supply from the slope wellhead. When pH value id recovered up to the normal value ECP is started into operation from the vertical wellhead and supply from the slope wellhead is returned back to normal operation mode. |
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In method for well completion including pumping of acid solution into open horizontal hole in the mode of jet impact such impact is attained due to a jet delivery by a jet nozzle at the end of a flexible flush-joint pipe. The nozzle is placed at the borehole bottom. The acid solution is pumped with circulation through the well mouth; while acid solution is circulating the flexible flush-joint pipe is lifted simultaneously from the well with the speed not exceeding speed of the borehole filling by the acid solution. When horizontal hole is filled with the acid solution, the solution is overflushed into the stratum with staged pressure build-up and exposure at each stage. The flexible flush-joint pipe with a nozzle is placed again at the borehole bottom and the operation of borehole filling and overflushing is repeated again. Soaking takes place so that acid solution could react with the rock. The flexible flush-joint pipe is lifted to the interval of inert gas pumping, an inert gas is pumped and a build-up curve is recorded. Cyclic well killing is carried out in the mode of water pumping - soaking - oil draining till complete oil drain; thereafter a submerged pump is run-in and the well is input into operation. |
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Device for treatment of bottomwhole formation zone contains an air chamber with atmosphere pressure and length of 20-50 m connected to the first additional perforated chamber with seal layer, solid heat generating compound A with flame igniter, combustible high-strength compound B and breakable calibrated membrane located inside; the first added perforated chamber by means of a coupling with holes is connected to the second added inlet chamber with combustible high-strength compound C, igniter and breakable calibrated membrane located inside; the second additional perforated chamber by means of a coupling with added air chamber with length of 1.5-3 m connected by means of a coupling and metal adapter with to inlet chamber that is made of elastic plastic material with seal layer, solid acid generating compound D with igniter located inside; in the metal adapter there are drilled holes; compound A generated heat and gas of the following components by wt %: ammonium nitrate 35; sodium bichromate 2; barium nitrate 15; aluminium ASD-1 1.5; iron-aluminium thermite 31; epoxide compound (mixture of ED-20 tar, EDOS plasticiser and AF-2M hardener) 15.5; compound B is made of the following components by wt %: ammonium nitrate 30-40, calcium carbonate 5-10, the above epoxide compound 50-65; inside the added inlet chamber there is a layer of glass sealant and solid gas generating compound E made of the following compounds by wt %: ammonium nitrate 70, sodium bichromate 1, the above epoxide compound 29; compound C is made of the same composition as compound B; compound D is made as thermal-gas-chemical solid fuel with a layer of glass sealant and a layer of epoxide compound on top of it; the above fuel consists of the following components by wt %: ammonium nitrate 12-16, lithium fluoride 1-3, barium nitrate 5-8, aluminium ASD-1 0.7-0.8, iron-aluminium thermite 14-16, hexachlorane 20-30, polytetrafluoroethylene 20-30, the above epoxide compound 5-10. The method for treatment of bottomhole zone (BHZ) includes delivery of the above device by a wireline, combustion of compound D and formation of maximum quantity of chemical agents, holding for the purpose of reaction of acids produced during combustion with BHZ formation, running with installation of the coupling with holes at the level of treated stratum, opening of the chamber with length of 20-50 m, actuation of breakable calibrated membrane in result of layer-by-layer combustion of compounds A and B with implosion treatment of BHZ, removal of impurities from bottomhole stratum; during holding thermal-gas-chemical impact acts on the stratum for 30 minutes ad pressure can be corrected due to availability of holes in the metal adapter at fixed position of the above fuel inside the inlet chamber due to the above layers of sealant and compound with formation of gases heated up to high temperatures at high pressure within treatment range; opening of the chamber with length of 1.5-3 m is carried out by sequential actuation of the igniter, compounds E and C and breakable calibrated membrane located in the second added inlet chamber; after hydraulic shock there's another holding of the process for 30 minutes; when the chamber with length of 20-50 m is opened combustion of compound A takes place with formation of gases heated up to high temperature at high pressure within treatment range. |
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Stimulation method of formation fluid influx from well Stimulation method of formation fluid influx from the well consists in lowering to the well of a tubing string. Counter pressure on the productive formation is decreased owing to replacing the liquid column with liquid-gas mixture (LGM) at observance of the required value of depression on the productive formation. Before the tubing string is lowered, its lower end is equipped with a remote subsurface pressure gauge and a filter. The tubing string is lowered to the well so that the filter is located opposite the formation perforation interval; after that, treatment of the bottom-hole zone of the formation is performed using a chemical method with process exposure for reaction. Then, the tubing string is lowered further so that the filter is located below the formation bottom, and into the inter-string space there lowered is a string of flexible tubes (FT) 100 m below the liquid level in the well. The liquid column is replaced in the inter-string space of the well with LGW and lowering of the FT string is continued. When lower end of the filter of the tubing string is reached, lowering of the FT string is stopped; then, stimulation of the formation fluid influx is started by gradual reduction of density of pumped LGM till the required depression on the productive formation, which is controlled as per readings of the remote subsurface pressure gauge, is achieved. After completion of stimulation of the influx from the well there removed is FT string from the inter-string space of the well, and operating equipment is lowered to the well and the well is put into operation. |
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Method for reagent clay cake removal from well Method for reagent clay cake removal from a well involves preliminary lowering of the tubing to lower perforation holes, formation in the zone of perforation holes of the first bath by pumping to the well via the tubing of a clay cake removing solution, its exposure, removal, further formation in the same zone of the second bath of water solution of acid with its being forced through the perforation zone to the formation and removal of the second bath by flushing; development of the well. As the clay cake removing solution, water solution of caustic soda with addition of surface active substance (SAS) is used. When the tubing is being lowered to the ell, it is equipped with a packer. Then, at open casing valve there performed is formation of the first bath by pumping of the above water solution of caustic soda via the tubing string, and the specified water solution of caustic soda is delivered to the formation by its being forced with process liquid via the tubing. Them the packer is set at the depth of not less than 50 metres above the treated formation, and forcing of water solution of caustic soda is performed with process liquid to the formation without exceeding allowable pressure on the formation; then, the well is kept for 10 hours for reaction under pressure not exceeding allowable pressure on the formation. Then, the packer is unpacked, and the working face is flushed by reverse flushing with process water by additional lowering of the tubing to the distance of 1-1.5 metres till the working face. Then, the packer is lifted so that it can be located at the depth of not less than 50 metres above the formation. Then, in the same zone there formed is the second bath by pumping of clay-acid solution with addition of Katapin KI-1 reagent on the basis of the fact that volume of clay-acid solution shall be 0.5-1 m3 per metre of the formation. The above clay-acid solution is forced with process fluid via the tubing to the formation; then, the packer is set and forcing of clay-acid solution is performed with process fluid to the formation without exceeding allowable pressure on the formation. Reaction exposure is performed during 1-2 hours. Then, well swabbing is performed via the tubing in the volume of 1.5-2 of the well volume. Then, the well injection capacity is determined at the pressure not exceeding maximum allowable pressure on the formation. When the required well injection capacity is not achieved, the above operations are repeated maximum for three times till the required well injection capacity is achieved. |
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Method for increasing oil recovery of deposit in carbonate reservoirs of fracture-pore type Method for increasing oil recovery of the deposit in carbonate reservoirs of fracture-pore type involves formation of a group of production wells with an injection well in the centre so that the injection well can be located in the lower part of the deposit structure in relation to production wells, oil recovery from the group of wells watered out with bottom water, forced extraction of fluid from the injection well till the response of the neighbouring wells to that action and reduction of formation pressure in the area of responding production wells. After steady reduction of formation pressure in the area of responding production wells by more than 10 %, each of them is pumped with waterproof compound that is strengthened under action of chlorhydric acid in the volume of 15-20 m3. After waterproof compound is cured, forced extraction of the fluid is stopped and acid bearing compound in the volume of 0.4-1.0 m3 per metre of oil saturated part of the formation is pumped to each well treated with waterproof compound. Responding production wells are brought into operation. |
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Method for bottom-hole zone treatment Method for formation bottom-hole area treatment includes mounting of oil-well tubing in the well below perforation holes, determination of technical condition of production string and character of production formation saturation in perforation zone on the base of geological-geophysical researches data, pumping and squeezing down to the formation water solution of alkali metal supersalt with holding for reaction for 10-12 h, extraction of reaction products from bottom-hole area by well blowing by inert gas or gas from well-donor through casing annulus, pumping and squeezing down to the formation hydrogen chloride, holding for reaction for 6-8 h, well development by gas from well-donor or inert gas. |
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Acidic aqueous solution containing chelating agent and use thereof Invention relates to an acidic aqueous solution containing a chelating agent and an acid, wherein the chelating agent is glutamic N,N-diacetic acid (GLDA) or a salt thereof and wherein the amount of GLDA or the salt thereof is 20-60 wt %, based on the weight of the aqueous solution, and wherein the acid is selected from hydrochloric acid, hydrobromic acid, hydrofluoric acid, hydroiodic acid, sulphuric acid, nitric acid, phosphoric acid, formic acid, acetic acid, citric acid, lactic acid, malic acid, tartaric acid, maleic acid, boric acid, hydrogen sulphide or a mixture of two or more of these acids, and use of said solution in cleaning processes, precipitation processes or processes of removing salt deposits, at oil fields in completion and stimulation by acid treatment, fracturing and/or deposit removal. The acidic aqueous solution has pH below 3. |
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Development method of bottom-hole zone of terrigenous oil formation According to the method of development of bottom-hole zone of terrigenous oil formation, before pumping of acid solution well is killed by solution of alkali metal hydroxide adding potassium and/or natrium chloride in quantity 0-35 wt % to obtain optimum density of composition, then well is pumped with aqueous solution containing 4-8 wt % of chlorhydric acid and 0.5-1.5 wt % of fluorhydric acid adding versene (trilon "B") in quantity 0.01-0.5 wt %, sodium dodecylsulfate in quantity 0.01-0.1 wt %, then aqueous solution of oil wetting agent NG-1 with concentration 0.01-2 wt % is pumped into formation. |
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Method of well bore zone treatment of production well Method of well bore zone treatment of production well involves determination of material composition of formation rock in the treated zone by means of carbon-oxygen logging (COL) immediately after the well drilling, at the following formation rock component ratio: quartz - not more than 50 wt %, clay - more than 10 wt %, and content of a layer of bitumen-resin-paraffin substances in oil of more than 30 wt %, and temperature in the well bore zone of 80-100°C; as treatment agent, Khimeko TK-3 acid composition diluted with hydrochloric acid (3%) is used in the ratio with the latter of 1:(2÷4) by weight respectively. |
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Treatment method of bottom-hole zone of horizontal or inclined well Treatment method of bottom-hole zone of horizontal or inclined well involves well treatment with the liquid providing the absence of absorption; viscous oil or fuel oil is used as the above liquid; then, the well is flushed with gas condensate; solution of acid is pumped to productive formation; technological exposure is performed for reaction of the acid solution; hydrocarbon solvent is pumped to perform the well flushing from residues of viscous oil or fuel oil and reaction products; well is developed by means of inert gas or gas from donor well. |
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Well bore zone treatment method Well bore zone treatment method involves determination of formation rock composition in the treated zone by means of carbon-oxygen logging (COL) immediately after well drilling and at content of carbonates in the formation rock of more than 5 wt %, irrespective of clay and quartz content, brine water mineralisation of 200-250 g/l, iron content of 2000-5000 ppm, content of layer of bitumen-resin-paraffin substances in oil, which is equal to 30-40 wt %, and well bore zone temperature of 60-160°C; treatment agent there used is the solution of "Khimeko TK-2K" Intensifying Compound in the ratio of the latter and the solvent equalling to 1:(1-5) by weight respectively. |
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Development method of bottom-hole zone Bottom-hole zone treatment method involves the transportation to the working face of the device by means of a wireline, which consists of an air chamber ending with a receiving chamber with the composition located in it and generating the gas during combustion, which releases the mixture of chlorhydric and hydrofluoric acids at thermal destruction, combustion of gas-generating composition and formation of heated gaseous products at increased pressure at treatment interval, process exposure for deeper reaction of chlorhydric acid with the rock, opening of the air chamber at the specified time period due to operation of the combustible diaphragm with igniter, which is installed at its bottom, and export of contaminants from the bottom-hole zone; as the above gas-generating composition there used is the mixture containing the following, wt %: ammonium nitrite grade B 32-33, hexachloroethane 51-53, plastic fluor FP-4 15-16. |
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Method of bottom hole formation zone processing Invention relates to oil industry. Proposed method comprises injection and driving acid agent into productive bed, process holding and extracting the products by depression effects. Note here that said acid agent comprises the following components in wt%: halogen acid - 0.5-5.0, acetic, or citric, or boric, or formic, or chloroacetic, or alkyl benzene sulfonic acid - 8.0-85.0, surfactant - 0.2-5.0, complexing agent - 0.1-1.0, water making the rest. In compliance with second version, prior to injecting said acid agent, bed is subjected to implosion effects. |
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Invention relates to construction, completion and pull-out of holes. Proposed method comprises adding peroxide compound into mud used for tailing-in and flushing including polysaccharides and mudding agent to be replaced by acid process fluid including said peroxide compound, acid and water, curing in reaction with subsequent removal of reaction products from the bed. Said peroxide represents urea peroxyhydrate, or sodium peroxyborate, or sodium percarbonate. It includes also adding said compound in concentration of 0.5-1.0 wt % to mud solution during circulation in last lift of drilling tool from the well and lowering of tubing with curing said composition in reaction for art least four hours. Note here that acid process fluid comprises the following components in wt %: said peroxide compound 0.5-3.0, hydroxycarboxylic, citric or lactic acid 5.0-10.0, nonionic surfactant - oxanol or neonol "АФ"9-12, or LML-4312, or "МЛ"-80 0.005-0.02, saline water making the rest. Note here that density of said acid process fluid equals that of mud solution used in tailing-in, or differs therefrom by not over 10%. |
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Method of carbonate bed processing Invention relates to oil industry. Proposed method comprises injecting urea-formaldehyde resin-based cementing composition with acid buffer solution as hardener, and, additionally, injecting said acid buffer solution as delayed-action acid penetrating into oil-saturated portions of reservoir. Acid buffer solution with pH 2.0-5.0 in amount of 10-30 wt % per 100 wt % of urea-formaldehyde resin is used as hardener. |
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Method for performing pulse hydraulic fracturing of carbonate formation Method involves lowering to the well of tubing string, pumping of fracturing fluid with a pump unit via discharge line to tubing string, formation of pressure drops between annular space, bottom-hole zone and cavity of tubing string by means of periodic pressure pulses in bottom-hole zone in the form of moving fluid mass wave. Annular space of well is sealed with packer installed above roof of formation subject to hydraulic fracturing, and on the end of tubing string there arranged is pulse generator. Drain valve is installed above pulse generator, but below packer as a part of tubing string. Hydropulsation compensator is installed on the well head for protection of pump unit against high pressure surges in its discharge line. Hydraulic fracturing of formation is performed by pulse pumping of fracturing fluid at the pressure exceeding crack opening pressure by 20-25% during 20-30 minutes. After that, pumping of acid solution is performed in pulse mode. For that purpose, chlorhydric acid solution (10-15%) in quantity equal to 1.3-2 m3 per 1 m of perforated formation thickness, but not less than 10 m3 is used. After that, well is closed and pressure reduction and acid reaction is awaited; drain valve is destructed and well is developed by swabbing via tubing string. Then, packer is released and tubing string is removed from the well. |
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Interval treatment method of bottom-hole zone of oil-gas well formations (versions) As per one of versions of the methods productivity of formations or their interlayers and boundaries and distances between them are determined, acid compounds are selected for treatment of each formation of interlayer. After that, inflatable packer-plug is lowered to unplugged well through production tubing using a flexible pipe equipped with spring centraliser when distances between formations or their interlayers differ considerably. The above packer-plug is installed in the well below the bottom of lower formation or interlayer and packed. Then, flexible pipe is detached from inflatable packer-plug and moved to the surface. After that, inflatable packer is lowered to the well using flexible pipe equipped with spring centraliser, installed above roof of lower formation or interlayer and packed. After that, acid compound chosen for treatment of that formation of interlayer is pumped through flexible pipe to lower formation or intelrayer. Acid compound is forced to bottom-hole zone of lower formation or interlayer to the depth of colmatage zone, kept for the period of its reaction with colmatage particles contained in bottom-hole zone, gas inflow is induced from lower formation or interlayer, reaction products are removed together with gas via annular space between flexible pipe and tubing string till complete recovery of productivity of lower formation or interlayer, and well is performed with regard to flame. After that, inflatable packer is unpacked and removed from the well using flexible pipe. Then, catcher is lowered to the well using a flexible pipe, connected to inflatable packer-plug, unpacked and moved with catcher below bottom of above located upper formation or interlayer, packed; inflatable packer is lowered using flexible pipe equipped with spring centraliser, installed above roof of the above located upper formation or interlayer and packed, and similar acid treatment with acid compound selected for treatment of that formation or interlayer is performed. |
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Method for defining well characteristics, formation bottom-hole zone Method for defining well characteristics, formation bottom-hole zone includes reagent pumping via tubing with closed tubular annulus, measurement of reagent flow rate at the well mouth and pumping pressure in bottom-hole zone. Measurement data is calculated for bottom-hole conditions. Accumulated flow rate and labour input per reagent flow unit in well bottom-hole zone is determined. These indices are used for definition of current formation conductivity change. Before reagent pumping fresh water is pumped into formation via tubing till well-head pressure reaches Phead=10 MPa with measurement of this pressure change in time and volume of pumped water. Their analysis is used to define initial conductivity of formation bottom-hole zone. After that there performed is an operation of bottom-hole treatment by reagent that is gassy fluid with water solution surfactant ML-81B or water solution of hydrochloric acid HCl. After that fresh water is pumped into formation similarly to the initial operation and final conductivity of formation bottom-hole zone is determined. After comparison of initial and final conductivity of bottom-hole zone there defined is a change of formation bottom-hole zone conductivities. If bottom-hole zone conductivity decreased or its increase is less than 10%, then additional treatment of bottom-hole zone is carried out by this or other reagent. |
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Acid treatment method of bottom-hole oil formation zone Acid treatment method of bottom-hole oil formation zone involves pumping of diverter -hydrocarbon gel prepared using Khimeko-N gel shaper, Khimeko-N activating agent and diesel fuel and further treatment at least of one low-permeable zone of formation with chlorhydric acid with concentration of 12% to 24%; at that, chlorhydric acid is used with decreasing concentration and volumes at repeated treatment operations. |
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Method of hydraulic fracturing of carbonate formation Method of hydraulic fracturing (HF) of carbonate formation in well includes perforation of well walls in required well interval by channels with depth not less than length of stress concentration zone in rocks from well shaft, lowering of pipe string to HF zone with sealing of intertube space by packer above perforation interval and cyclic pumping of fracturing jelly-like liquid to well. Before HF performance well is filled with process liquid in the volume of 0.2-0.4 of well shaft volume, total volume of pumped fracturing jelly-like liquid is calculated by formula: Vj=k*Hp, where Vj - volume of pumped fracturing jelly-like liquid, m3; k=1.4÷1.6 - conversion factor, m3/m; Hp - opening interval length, m. Fracturing jelly-like liquid is pumped in equal portions in 3-5 cycles, after that acid portions are pumped in the volume of 0.7-0.75 of volume of fracturing jelly-like liquid, after completion of the last pumping cycle marketable oil or fresh water is pumped in one-and-a-half volume of pipe string with further exposure during 1-2 hours, after that products of acid reaction with rock are removed, packer is dismounted and removed from well with pipe string. |
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Well bore zone treatment method In well bore zone treatment method involving determination of composition of formation rock in the treated zone by means of hydrocarbon-oxygen logging - HOL, and at carbonate content in formation rock of more than 5%, and clay - less than 10%, irrespective of quartz content, as treatment agent there used is water solution of chlorhydric acid with concentration of 10-18% with additions of Neftenol-K in quantity of 2-5% and IKU-118 in quantity of 0.10-0.30% of volume of water solution of chlorhydric acid. Invention has been developed in dependent claims. |
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Method of formation bottomhole zone acid treatment Method of formation bottom-hole zone acid treatment includes two pumping cycles of 10-15% water solution of hydrochloric acid with the use of displacement fluid each containing pulse solution pumping at 1-4 MPa, pumping of this solution at constant pressure, technological exposure for 2.5-3.5 hours for reaction and reaction products removal with further bottom-hole cleaning by flushing fluid. Solution pulse pumping is carried out for 5 minutes with 6-10 minutes breaks. Pumping at constant pressure is done by portions of 2-4 m3 with holding 2-4 hours between portions. Pumping of solution portions is stopped at pumping pressure exceeding 3 MPa. Between solution pumping cycles there pumped is oil-acid composition containing 24-26% solution of hydrochloric acid in oil with volume of 1-4 m3 at 7 MPa. Oil is used as displacement and flushing fluid. |
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Method of bottom-hole zone treatment of low-permeable terrigenous formations (versions) Method of bottom-hole zone treatment of low-permeable terrigenous formation according to the first version consists in flushing of killed well, sequential pumping of methanol, 18-20% solution of hydrochloric acid for acid bath installation, then the well is repeatedly pumped by 18-20% solution of hydrochloric acid and buffer-gas condensate, acid composition is squeezed into bottom-hole zone of formation by inert gas, then mud acid solution is pumped, gas influx from formation is caused and then reaction products are removed together with gas flow, the well is treated through flare line with removal of reaction products till it reaches design conditions and then the well is placed under production. Method of bottom-hole zone treatment of low-permeable terrigenous formation according to the second version consists in sequential pumping of methanol, 18-20% solution of hydrochloric acid and buffer-gas condensate into non-killed well through tubing casing, acid composition is squeezed into bottom-hole zone of formation by inert gas, then mud acid solution is pumped, gas influx from formation is caused and then reaction products are removed together with gas flow, the well is treated through flare line with removal of reaction products till it reaches design conditions and then the well is placed under production. |
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Method of formation face zone development Method of formation face zone development consists in pumping the gas-generating and acid-based reagents, where gas-generating reagent is the compound that includes, wt %: urea 28.4-38.4, sodium nitrite 18.2-27.6, water - the rest, and acid-based reagent is the compound that includes, wt %: inorganic acid 5.2-60.9, surface acting agent 2.4-3.5, ferrum inhibitor 1.4-2.3, flotation agent 7.0-11.4, water - the rest. Note that the proportion of gas-generating and acid-based reagents amounts 1:(1-3), after pumping of the reagents they are held. |
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Method for formation acid treatment The method for formation acid treatment includes detecting zones of various openness in the treated formation, injecting a portion of hydrochloric acid solution into the higher openness zone, subsequent squeezing of viscous fluid based on oil by the hydrochloric acid solution with a surface-active agent, squeezing of the hydrochloric acid with the surface-active agent into the lesser openness zone in cyclic mode, extraction of used hydrochloric acid from the well at the final cycle, furthermore, the concentration of hydrochloric acid is reduced with every cycle of its application. |
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Acid treatment of an oil exploitation well bottom-hole area FIELD: oil producing industry. SUBSTANCE: invention belongs to the oil producing industry and may be used for acid treatment of an oil exploitation well bottom-hole area characterized by the uncapped productive formation with carbonate reservoir rock. Acid treatment of an oil exploitation well bottom-hole area technique involves running-in of a flexible flush-joint coiled tubing unit along the annular space with the subsequent injection into the well, advance of the flexible flush-joint coiled tubing up to the well bottom, oil injection up to the full change of killing fluid to the oil, removal of flexible flush-joint coiled pipes of a coiled tubing unit up to the roof of the productive accumulation, shutting-in a well, injection of soldering acid solution to the bottom-hole area through the flexible flush-joint coiled pipes of a coiled tubing, pulling of the bottom part of flexible flush-joint coiled pipes of a coiled tubing unit to 0.8-1.2 m and injection of soldering acid solution up to the reach of productive formation bottom, running of the bottom part of flexible flush-joint coiled pipes of a coiled tubing unit to the centre of the well and curing within the period of 2-3 hours., gradual pulling of the bottom part of flexible flush-joint coiled pipes of a coiled tubing unit to the well bottom and simultaneous oil injection with the borehole fluid drainage through the annular space, flushing-out of well with oil, removal of the bottom part of flexible flush-joint coiled pipes of a coiled tubing unit and closing of the annular space, carrying out of advancing and closing operations and launching of a well. The aforementioned adaptation requires a well with the uncapping productive formation with the permeability not less than 0.01 mcm², formation pressure not less than or equal to 7 MPa, productivity index not exceeding 0.1 m³/day*atm. Immediately prior to processing, the well production rate within the bottom-hole pressure conditions should be not less than or equal to 1.5 MPa, while the formation dispersion should be not less than or equal to5.5 MPa. Within the processing the acid volume should be not less than 0.5-1 m³ for 1 m of the perforated load. Productive formation interval is perforated no sooner than in a year prior to such processing with perforation of the productive formation interval amounting to more than 10m. EFFECT: efficiency enhancement of acid treatment of an oil exploitation well bottom-hole area. 2 ex |
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Development method of bottom-hole formation zone In processing method of bottom-hole formation zone, which involves pumping to the formation of magnesium granules with further pumping of acid compound, first, hydraulic fracturing of the formation is performed with further pumping of mixture of magnesium granules and propane with fluids on hydrocarbon or water basis. Then, to the processed zone of the formation there pumped is combustible oxidation composition (COC) which contains oxidiser, catalyst decreasing the value of the temperature required for the beginning of oxidation reaction, surface-active substance required for removal of hydrocarbon film from magnesium, and water. After oxidation reaction is completed and additional cracks are formed, acid compound increasing the size of the formed cracks is pumped. |
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Procedure for production of fluids from acidulous cemented sections of underground beds Procedure for stimulation and stabilisation of region of underground bed consists in: delivery of acidulous liquid into region of underground bed and allowing acid, at least partially, to dissolve part of region of underground bed, in pumping cementing liquid containing agent increasing stickiness and including water stickiness increasing agent, in delivery of liquid for successive flushing into region of underground bed and in pumping replacing liquid into underground bed directly upon stage of delivery of acidulous liquid into region of underground bed. |
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Method of sour well intervention in terriogenous reservoir Method of sour well intervention in a terriogenous reservoir involves injecting into a productive formation a first processing medium containing, wt %: hydrazine hydrochloride N2H4·2HCl 10.8, organic phosphonic acid derivative 0.5, surface-active substance 0.5, corrosion inhibitor 0.5, water the rest. Further, after curing of the processing medium, a buffer liquid containing the surface-active substance in the concentration 0.5-0.8 % is injected into the reaction mixture. It is followed with injection of a second processing medium containing, wt %: hydrazine hydrochloride N2H4·2HCl 10.8, ammonium bifluoride NH4F·HF 4.3, organic phosphonic acid derivative 0.5, surface-active substance 0.5, corrosion inhibitor 0.5, water the rest. Further, after curing of the second processing medium, well completion is performed. |
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Procedure for treatment of bottomhole zone of well Procedure for treatment of bottomhole zone of well consists in forcing acid reagent through well into zone of pay, in process conditioning and in removal of reaction products from treated zone; as acid reagent there is used reagent of multi-functional action RMA-K in mixture with montmorillonite dispersed to dimension of particles from 10 to 200 nm at ratio of components, wt parts: 1: (0.001-1). |
Another patent 2513078.