Method for preventing deposition of sodium chloride in formation bottom-hole zone and wellbores of underground gas storages

FIELD: oil and gas industry.

SUBSTANCE: method for prevention of deposition eliminates formation thereof by maintaining concentrations of sodium chloride dissolved in formation water at a level excluding its crystallization. Maintenance of specified value of concentration provides injection of humidified gas into the underground storage to exclude the process of absorption by gas moisture from formation water. The required amount of fresh water to humidify the injected gas is defined as the difference in absolute maximum gas moisture content in the formation conditions and absolute moisture content of gas supplied from the main pipeline for injecting into the underground storage.

EFFECT: increased duration of wells and storages operation, and total volume of extracted gas, increased overhaul period, operation for liquidation of salt plugs is eliminated.

4 dwg, 1 tbl

 



 

Same patents:

FIELD: mining.

SUBSTANCE: method presumes the action in view of types of deposits on the cleaned surface by setting of the respective values of physical parameters of the effecting working medium, geometry of a cavitator and its position with reference to the cleaned surface: x¯, Pc and Ps, where x¯ - relative distance from the cavitator outlet to the cleaned surface, Pc - dynamic pressure downstream the cavitator, Ps - static pressure in the flooded cavity. Values of the parameters x¯ and Pc are pre-set within the limits: x¯=550, Pc=5-45 MPa. Static pressure Ps in the flooded cavity is pre-set according to the condition Ps=0,075Pcexp(0,4x¯) with providing of pulsation of the jet cavitating flow with a variable frequency and achievement of a resonance of layers of deposits. The pulsation of the jet cavitating flow is provided using a sweep generator. Occurrence of resonance of layers of deposits is identified by growth of concentration of pollution of destroyed layers in the taken-away flow, the frequency of pulsation of the jet cavitating flow is registered, at this frequency the cleaned surface is processed further.

EFFECT: improvement of efficiency of cleaning and maintenance of wells and pipelines increases.

9 cl, 5 dwg

FIELD: oil and gas industry.

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

EFFECT: higher efficiency and stability of the well operation.

2 cl, 3 dwg

FIELD: oil and gas industry.

SUBSTANCE: device contains installed on the sucker-rod string the reception branch pipe in the form of a feather, the check dish-shaped valve, the check ball valve, the filter, the hydrodynamic valve, the throttle coupling, the hydrostatic valve, the knock-off valve; the valve with compulsory operation. The hydrostatic valve includes a plunger with cross-over holes and is fitted with sealing rings, and its internal cavity is fitted with circulating microvalves . The hydrodynamic valve includes the housing, the adjusting nut, the spring, the thrust, the conical valve and the branch pipe. The housing of the lower check dish-shaped valve is implemented as a centraliser with the maximum allowable diametrical sizes for the casing string of the specific well.

EFFECT: reliability and quality of cleaning of the bottomhole zone of formation and the well face with ensuring of the device operability in the inclined directed and horizontal wells and adjustability of cleaning process.

4 dwg

FIELD: oil and gas industry.

SUBSTANCE: method comprises pumping into the annular space of the well of emulsifier at a rate of 60-80 g per 1 m3 of extracted water, discharge of gas from annular space into the air. After formation in annular space of finely dispersed water-oil emulsion it is flushed into the tubing string by heat carrier until full removal of asphaltene-resin-paraffin deposits.

EFFECT: well cleaning efficiency improvement.

3 ex

FIELD: mining.

SUBSTANCE: device contains a housing, a connecting branch pipe, a seat with longitudinal grooves and a throttle channel, a pusher with a punched cage with a seat and a spherical valve inside, a ring piston with a hollow rod, a nut. Between the hollow rod and the barrel a ring chamber is formed which is hydraulically connected by a circulating hole with the ring channel between the barrel and the housing and, through the throttle channel in the seat body, with the axial channel of the extender. The ring piston is rigidly connected with the pusher fitted with the transitional coupling with the punched cage inside, freely installed with a possibility of interaction by the end valve on the outer side with a bearing surface in the connecting branch pipe which is rigidly connected with the housing through the extender. The nut is connected with a barrel and forms movable connection with the hollow rod. The rod is rigidly connected with the ring piston. The area of the ring piston from the side of ring chamber is smaller, than the area of the ring piston being sat on the seat.

EFFECT: design simplification, improvement of efficiency of destruction of sand plug.

3 dwg

FIELD: oil and gas industry.

SUBSTANCE: marketable oil pre-treated with a hydrogen sulphide neutraliser till complete neutralisation of the latter is pumped to a pipeline. Replacement of the transported product in the pipeline is performed by pushing-through with preservation liquid of two elastic dividers, between which a concentrated neutraliser solution is arranged. Replaced liquid is displaced to a storage tank under the level of the hydrogen sulphide neutraliser solution, for example Darsan-N neutraliser.

EFFECT: method has ecological cleanness, provides for personnel safety at preservation and depreservation of the pipelines and does not prevent utilisation of neutralisation products.

2 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: proposed device comprises barrel rigidly secured at flow string and provided with holes made in its wall and perforated casing pipe section-case. Said flow string can displace up and down with working elements secured thereat along the case. Said barrel has opposite upper and lower working elements composed by fixed swirler case, swirler and swirler guide cone that make a circular slot. Inner spaces of working elements are aligned with the barrel wall holes. Additionally, said barrel is provided with bypass channel of directed overflow to communicate annulus under lower working element and that above it. Resilient shutter is arranged at the barrel lower end.

EFFECT: higher reliability and quality of cleaning, swabbing effect.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: hydraulic hammer is installed on the lower end of a flexible pipe and lowered to a well to a location place of a sand-clay plug. A coiled tubing unit is located on the well head. A bench of foam-forming liquid (FFL) of design length is formed in an axial duct of the flexible pipe. Mechanical action on the sand plug surface is performed by the hydraulic hammer at its movement and pumping through it of FFL benches with further generation of foam in inter-pipe space in each bench by bubbling through it of a bench of gas supplied from the axial duct of the flexible pipe through the hammer. After the plug is removed, development of the well is performed by continuous supply of gas to the axial duct of a flexible string of pipes and by invoking an influx at reduction of pressure below the formation one.

EFFECT: improving efficiency of removal of a sand-clay plug and development of a well.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes running in of a working part with channel or channels on its surface, which is placed at outer surface of the tubing string, up and down movement of the tubing string with overflow of working fluid filling the well bore through channel or channels in the working part. Overflow of working fluid from annular space below the working part to from annular space above the working part is made through bypass channel inside the tubing string bypassing channel or channels at surface of the working part in case of downward motion. Broken combatant is removed by fluid delivered from the formation with additional of working fluid to the tubing string from the surface without its pumping from the surface through the treated zone.

EFFECT: improved treatment efficiency without limitation of simultaneously treated thickness of the perforation interval.

5 cl, 3 dwg

FIELD: oil and gas industry.

SUBSTANCE: while implementing the method a tubing string is run in to a well up to a bottomhole with a tube having a diameter more than the diameter of the tubing string with triangular windows and inner sharp tabs faced upwards under an angle of 25-30° to the vertical, circulation of the borehole fluid with a consumption rate within limits from 3.5 up to 8 l/s through the annular space, tube and tubing string through a holding tank in the volume not less than the well volume and lifting of the tubing string with the tube from the well.

EFFECT: raised efficiency of the well cleaning.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: stratum is impact cyclically, at that each cycle of impact includes gas injection to the stratum with further gas extraction. The stratum is impacted during 10 cycles at least. In each cycle current formation pressure as well as gas extraction (or injection) volume is measured simultaneously in gas- (Pt''ф'') and water-bearing (Pt''фв'') zone of the storage facility, then considering the measured parameters the design pressure in the underground storage facility (Pt''P'') is defined for the facility operation mode without gas losses and operation mode with gas losses. Then function (F) is defined as arithmetic mean value of deviations (Pt''P'') from (Pt''ф''), which are received for each ith measurement for the facility operation mode without gas losses and the function (Fy) for the facility operation mode with gas losses and when inequality Fy<F is satisfied the summary is made about available gas leaks in the storage facility.

EFFECT: simplifying control of gas leak-tightness, improving reliability and safety of the underground storage facilities made in the water-bearing strata.

1 tbl

FIELD: oil and gas industry.

SUBSTANCE: method includes alternating gas injection and extraction to/from the well and during their alternation one part of the reservoir bed is isolated while the other is penetrated. According to the invention at the well construction stage the production string with a cement-inflatable packer is run in to the well and cemented; at that the packer divides the borehole annulus in the reservoir bed area into two conditional parts. The production string is perforated in both parts above and below the cement-inflatable packer. Thereafter a tubing string with a tubing-casing packer equipped with a circulation valve is run in so that when the tubing string is set to the production string the above circulation valve is placed below the cement-inflatable packer and above the tubing-casing packer between the perforated sections of the production string. Then the space between the production and tubing strings are filled with immiscible portions of the packer fluid. During further operation of the well injection of gas to the reservoir bed is made through the tubing string and lower perforation interval with temporary isolation of the upper perforation interval by one of the packer fluid portions while gas extraction is made through the upper perforation interval and tubular annulus with temporary isolation of the lower perforation interval by the other portion of the packer fluid.

EFFECT: increased efficiency of the method.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is related to the area of oil and gas industry and intended for operation of underground gas storage (UGS) operation. At UGS with arranged producers with storage collector opening cyclic injection of natural gas is made with creation of its buffer and active volume and extraction of the gas active volume. In process of the UGS operation carbon dioxide in injected to the lower part of the storage thus replacing natural gas in the buffer volume. At the end of natural gas extraction cycle the boundary line of carbon dioxide and natural gas reaches the lower openings in the perforation interval of the producers.

EFFECT: invention ensures increase in active volume of stored natural gas in the UGS and reduction of costs for formation of the buffer volume.

FIELD: oil-and-gas industry.

SUBSTANCE: invention can be used in permafrost regions with hydraulically isolated lenses of underground smelt water bearing sand collectors, cryopag (CP), for burial of drilling wastes (DW). Proposed method comprises drilling of one injection well in CP and at least one CP relieving well. Besides, it includes pressure pre-decrease in CP by forcing water-sand pulp via said CP relieving well. Decreased pressure stabilised in injection well, uniform mix of drilling wastes and at least 10 wt. % of crushed ice made from sea water or water pumped from CP with additional of the mix of fluid hydro geological indicator (HGI). Note here that drill wastes are continuously subjected to audio frequency vibrator effects nearby suspended tubing shoe. Injection is continued unless HGI traces appear in pulp forced from relieving well. Then, drilling waste injection into CP, their vibration and pumping of pulp from CP are terminated to eliminate RW. For burial of extra volume of drilling wastes, another RW is constructure to go on injecting of drilling wastes via the same IW with their vibration and application of another RW.

EFFECT: ecologically safe and efficient process.

2 cl, 1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: in compliance with this method, seam is subjected to cycling, every cycle including gas injection therein with subsequent gas withdrawal. Cycling includes at least 10 cycles. Current seam pressure (Ptf) and gas withdrawal (or injection) volume are measures at regular intervals in every cycle. Measured parameters allowed for design pressure in underground storage facility (Ptd) is determined for facility operation without gas leaks and with leaks. Function (F) is defined as mean arithmetic value of (Ptd) deviations from (Ptf) obtained at every ith measurement for operation without leaks and function (Fl) for operation with leaks. Given Fl<F, leaks are considered available.

EFFECT: simplified control, higher safety and reliability.

1 tbl

FIELD: oil-and-gas industry.

SUBSTANCE: proposed method comprises construction of wells with exposure of geological structure with pods and pool cap, injection of gas into said structure to force formation water downward from pool cap with prevention of gas escape from the boundaries of geological structure and gas extraction from underground storage (UGS) top section. Note here that availability of superhigh-seam-pressure formation water deposits with dissolved and/or dispersed gas is checked in region with geological structure intended for underground gas storage. Production wells are made with exposure of said deposit, water with dissolved and/or dispersed gas is extracted there through and bypassed into aforesaid geological structure. Gas extraction from UGS is carried out after extraction of dissolved and/or dispersed gas from water and their immiscibility. Water with dissolved and/or dispersed gas is bypassed from superhigh-seam-pressure geological structure is carried out as pressure in UGS decreases owing to gas extraction.

EFFECT: use of dispersed and dissolved gas in abyssal aquifers.

1 ex, 1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to environmental protection against man-made contaminants, hothouse gases and power source synthesis. In compliance with proposed invention, this method comprises isolation of aquifer with, preferably, with cropout and feed area as, for example, a river, lake, sea with total active filtration conditions. At least one local trap is isolated in isolated bed. Selected aquifer and local trap are prepared for commercial use with definition of isolated aquifer water chemical composition and that of rocks by core sample. Carbon dioxide is injected to isolated aquifer via one injection well located on aquifer feed zone side to allow downstream of injected carbon dioxide in aquifer. Catalytic reaction of polycondensation synthesis of injected carbon dioxide and water to form hydrogen, oxygen and methane homologues.

EFFECT: higher efficiency of recovery for replenishment of hydrocarbons stores and development of new oil and gas deposits.

11 cl, 4 dwg

FIELD: transport.

SUBSTANCE: proposed storage comprises reinforced concrete tank mounted on the bed of compacted soil and heat-isolation layer and having vertical sidewalls, said being surrounded by pliable layer at outer side surface and heat- and water-insulated from liquefied natural gas. Storage shaft is equipped with pipelines to fill said storage with said gas and its vapors and to discharge the latter therefrom. Said shaft extending from reinforced concrete tank to surface is equipped with tight hatches and staircase. Tank top is buried in the heat-insulation material layer. Note here that tank top features cross-section decreasing towards earth surface and is shaped to truncated cone and connected with said shaft by sealed flange joint. Aid tank top with flange joint are arranged at decreased spacing from frozen soil bottom surface.

EFFECT: simplified design.

3 dwg

FIELD: oil and gas industry.

SUBSTANCE: operating method of underground gas storages involves intermittent injection of gas by compressors, which is supplied from a main gas line through production and injection wells of an underground gas storage to a reservoir bed under pressure exceeding formation pressure; further extraction of gas from the underground storage for further gas supply to the main gas line. The above extraction from the underground storage and its supply to the main gas line is performed in a compressor mode that is performed till pressure in the reservoir bed reaches the value excluding allowable well water flooding. With that, a suction gas line of compressor is connected to a gas extraction pipeline from the underground gas storage, and a discharge gas line of compressors is connected to the main gas line.

EFFECT: improving operating efficiency of an underground gas storage.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention refers to a method for making a low-permeability screen in porous medium at underground gas storage in porous reservoir beds and can be used in oil and gas producing industry. According to the invention, first, required volumes of solutions are determined in interwell spaces; the amount of 0.5-0.55 of design volume of spike solution and spike solution itself are pumped subsequently to injection wells till gases appear in a relief well; after that, design volumes of the solution and gas, which provide minimum required width of a screen, are pumped to the unloading well; waste gas of compressor stations is used as gas for creation of a screen. Nonflammable and/or inert gases are used as gases for creation of the screen.

EFFECT: increasing the screen continuity, reducing the flow rate of foaming agent solution and consumed energy for pumping-in and pumping-out, economy of natural gas and improvement of environmental situation in the underground gas storage location area.

3 cl, 6 tbl, 4 dwg

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes performing a test pumping of liquid waste into absorbing well before operational pumping, while changing flow step-by-step. From equation of absorption base hydrodynamic parameters are determined for calculation of predicted coefficients of operation characteristics of absorbing well and reserve well. During operational pumping of liquid waste together with thermometry along absorbing well shaft, registration of actual pressures and flow on pump devices, actual pressures on mouth in tubing pipes of absorbing well, actual pressures on face are additionally registered in absorbing well as well as pressures on mouth in behind-pipe space, actual loss at mouth in behind-pipe space, actual loss of waste on mouth, actual positions of face well, upper and lower limits of absorption range from well mouth. In reserve well actual pressures on face are registered, as well as actual positions of liquid level from reserve well mouth, upper and lower limits of absorption range. Prediction coefficients are compared for operation characteristics of absorbing well and reserve well to actual coefficients. 9 conditions of hydrodynamic bed conditions at reserve well and absorbing well are considered during pumping of waste. Specific actions of operator on each condition are described.

EFFECT: higher reliability and trustworthiness.

1 ex

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