Method for accumulation of cold in formation

FIELD: oil and gas industry.

SUBSTANCE: method for accumulating cold in the formation involves the use of a two-tube arrangement in a dual horizontal well, lowering of a first lift pipe with packer installation for separating the annulus and production of oil, lowering a second lift pipe of smaller diameter. Coolant is circulated by means of injection into the second lift pipe and lifting along the annulus. In this case, the formation is cooled simultaneously with production of oil from the well, as a result the conditions for keeping hydrates at the boundary of gas-oil contact are provided.

EFFECT: increased oil recovery of oil-gas condensate fields due to presence of hydrate barrier at the boundary of gas-oil contact.

1 dwg

 



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the oil industry and may be used in the operation of a horizontal well. According to the method well operation is performed. A pipe string is run down to the horizontal well. An insulating material is injected through the pipe string to a water-inflow interval of the productive formation. Oil is extracted until the horizontal well is flooded. Under the main borehole along the boundary of the oil-water contact an additional borehole is drilled from the horizontal well per 50 m longer than the old hole. The coil tubing is run down to the well complete from below with a hydraulic whipstock and a screen, which openings are covered hermetically by a hollow bushing. The process fluid is injected to the coil tubing thus creating an excess pressure. Simultaneously the coil tubing is moved down until it gets to the additional borehole. The coil tubing is run down up to the bottomhole of the additional hole. At the wellhead a top cementing plug is set into the coil tubing. An excess pressure is created in the coil tubing above the top cementing plug and the hollow bushing is moved thus opening the screen openings. Microcement grout is injected through the coil tubing and flushed to the additional hole and the bottomhole zone. Simultaneously the coil tubing is pulled out for the purpose of additional hole filling with the microcement grout. Flushing of the microcement grout is stopped when pressure increases in the coil tubing up to a permissible value. The coil tubing is pulled out from the well and the process is withheld for cement setting and hardening. The additional hole is cut off from the old hole by setting a bridge plug in a kickoff interval at the inlet to the offshoot. A pump is run down at the process pipe string to the old hole of the horizontal well and operation of the horizontal well is started. At water encroachment into the produced product the process pipe string with the pump is pulled out from the well, a geophysical study is performed and a water-producing interval is indentified in the horizontal well. The water-producing interval in the old hole of the horizontal well is isolated.

EFFECT: increased efficiency of the method due to the complete exhaustion of oil reserves from the productive formation notwithstanding the drawdown value.

4 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is referred to oil and gas industry, and namely to methods of automatic flow control at well operation of oil and gas deposit. According to the method injectors and producers equipped with pump units and electric motors are used. A passive sonar multiphase flow meter is mounted at the mouth of each well. Pressure, temperature and flow rate is defined continuously in real time for each phase, including water. The data are collected and transferred to automatic flow process control system continuously in real time. The data are averaged for a certain period of time. Average flow rate is processed and defined by phases for the selected period of time. The results are compared with preset parameters and based on flow rate data for each phase dependency of flow rate for each well is defined on pumped volume of brine water. Version of pump units operation with electric motors for producers is selected and maintained so that oil flow rate is maximum and pumped volume of brine water and power consumption is minimum. At that when design flow rate values are exceeded one of the following actions is performed: efficiency of pump unit is reduced due to reduced rate speed of the electric motor; efficiency of pump unit is increased due to increased rate speed of the electric motor; pump unit is stopped temporarily to accumulate oil in the bottom hole. Product of the producers is separated into phases and transported depending on the phase to oil and gas collection system or reservoir pressure maintenance system.

EFFECT: increased efficiency of the method due to increased oil flow rate, reduced volume of brine water pumped and reduced power consumption.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is referred to systems of oil and gas equipment automatic control and allows timely detecting of pre-emergency situations related to hydrate formation in gas equipment. According to the method gas pressure and temperature is measured periodically upstream and downstream gas equipment, gas flow rate through gas equipment or gas pressure drop is measured at orifice located in the gas flow passing through gas equipment. Then against measured values hydrate formation coefficient is formed for operating gas equipment and degree of hydrate formation is evaluated against deviation of this coefficient from the basic value determined in hydrate-free mode of gas equipment. In hydrate-free mode of gas equipment basic values of the above hydrate formation coefficient are used as technical state indicator for gas equipment.

EFFECT: method allows timely detecting of pre-emergency situations related to hydrate formation in gas equipment.

3 cl, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: according to the method fluid pumping from the well is alternated with fluid accumulation in the well at switched off pump set and average delivery in time is controlled for the purpose of matching with the well flow rate by changing speed rate of the pump shaft. Pump capacity in pumping process is controlled by a submersible flow rate meter placed at the pump output. Pumping out will be performed till the pump reaches the preset minimum pressure at suction and accumulation will be performed till the pump reaches the preset maximum pressure. Pressure value is controlled by means of a submersible pressure sensor. Frequency of the pump shaft rotation during pumping period is changed on the basis of readings of the submersible flow rate meter so that maximum value of efficiency factor is reached for the pump during pumping period. Time of accumulation is limited by regulations on motionless fluid in surface equipment in winter time by permitted decrease of oil temperature in the submersible electric motor and permitted frequency of stops and starts of the latter. Maximum pressure value for the cemented stratum is selected on condition of maximum oil production and for the stratum destructed intensely in extraction process on conditions of minimum discharge of mechanic impurities.

EFFECT: increased production and maintained reliability for submersible equipment due to its operation in the mode of maximum efficiency factor.

FIELD: physics.

SUBSTANCE: methods and systems for gathering, deriving and displaying the azimuthal brittleness index of a borehole are disclosed. Certain embodiments include various methods for calculating and displaying borehole measurements in real-time for geosteering and drilling operations. One embodiment of the disclosed method for calculating and displaying azimuthal brittleness includes a step of taking measurements of compressional and shear wave velocities as a function of position and orientation from inside the borehole. These velocity measurements are taken by an azimuthal acoustic device. Azimuthal brittleness is then derived based on the compressional and shear wave velocities.

EFFECT: high reliability of data of planning geological survey operations.

19 cl, 6 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes cyclic forced gas pumping from the annulus and pressure decreasing in it. Periodically the well flow header is partially closed. Pressure upstream the shutdown element of the header is increased to ensure the produced fluid supply to the expansion chamber of the tank with resilient element and to accumulate mechanical energy in the expansion chamber. Then full opening of the header shutdown element is performed. Pressure upstream the shutdown element is decreased, and fluid is displaced from the expansion chamber to the header due to the accumulated mechanical energy. Each cyclic volume increasing of part of the tank above the expansion chamber ensures annulus gas suction in it, and this volume decreasing ensures gas displacement to the header.

EFFECT: possibility of gas pumping from the annulus in tubing string of the well for different methods of mechanised oil production.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: group of inventions is related to oil production industry, in particular, to secondary and tertiary methods of enhanced oil recovery for beds with low oil saturation that envisage use of equipment for production of gaseous nitrogen with high pressure and temperature. Nitrogen compressor plant comprises a multistage piston-type compressor with a power drive unit made as diesel engine, and gas-separating unit. Output of the compressor intermediate stage is coupled to input of gas-separating unit. Output of gas-separating unit is coupled to input of the compressor stage, which follows the intermediate stage. At that nitrogen compressor plant includes heat exchanger, which working medium input is coupled to the compressor output. Input of the compressor heat exchanger is coupled to exhaust output of diesel engine. Gas-separating unit is made as a hollow-fibre membrane unit. Output of the heat exchanger working medium is coupled to input of additional heater. At that output of the additional heater serves as output of the station.

EFFECT: development of more effective means for oil extraction from low-permeable collectors complicated by high paraffin content.

8 cl, 4 dwg

FIELD: oil and gas industry.

SUBSTANCE: device comprises a pipe string run in to the well, a packer with a flow shutoff mounted in it. The packer is made as a hollow body with the upper row of openings placed above the sealing element in the packer. Inside the hollow body there is a pipe concentric to its axis and fixed rigidly to the pipe string from top and to the piston from bellow. The pipe with piston may be moved axially in regard to the hollow case of the flow shutoff. In the hollow body below the sealing element of the packer there is the lower row of openings. The piston is made hollow and plugged from below. Opposite the upper and lower rows of openings in the hollow body the piston is equipped with inner cylindrical sample capture and a row of feedthrough openings. In the hollow body above the upper row of radial openings there is a cam slot in the form of longitudinal groove and three transversal grooves. The transversal grooves are made from the upper, medium and lower parts of the lower part of the longitudinal grove. In cam slot of the hollow body there is a guide pin installed so that it may be moved axially and transversally. It is fixed rigidly in the piston above its upper inner circular sample capture. When the guide pin is placed in the transversal groove made of the medium part of the longitudinal groove, the device is designed to connect inner space of the pipe through a row of feedthrough openings of the piston, inner cylindrical sample capture, the upper and lower rows of openings with over-packer and below-packer space of the well. When the guide pin is placed in the transversal groove made of the upper part of the longitudinal groove, the device is designed to connect inner space of the pipe through a row of feedthrough openings of the piston, inner cylindrical sample capture, the upper row of openings with over-packer space of the well. The lower row of openings in the hollow body is sealed in tight-proof way by the piston. When the guide pin is placed in the transversal groove made of the lower part of the longitudinal groove, the device is designed to connect inner space of the pipe through a row of feedthrough openings of the piston, inner cylindrical sample capture, the lower row of openings with below-packer space of the well. At that the upper row of openings in the hollow body is sealed in tight-proof way by the piston.

EFFECT: simplified design of the device, improved reliability of its operation and expanded functionality.

3 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is related to oil and gas producing industry and can be used for annular gas bypassing to the flow string in wells operated by sucker-rod pump units. Task of the invention is to perfect design of the downhole device for annular gas bypassing in order to improve operational efficiency of the well sucker-rod pumping equipment notwithstanding temperature conditions of the well operation and pressure of annular gas. The device is placed in the well annular space over the well fluid level in the flow string collar. The device comprises a return valve and a radial hydraulic channel. In the collar lower part there is a radial hydraulic channel interconnected to the well annular space at the one side through the return valve and to the flow string cavity at the other side through a jet device. At that axes of the radial hydraulic channel and the jet device are crossed in the nozzle area of the latter. Besides the device comprises a flow string with a whipstock for gas-fluid flow in it. The whipstock is made as a bushing capable to be fixed in the flow string collar. Length of the whipstock for gas-fluid flow is less than distance between receipt and discharge of the jet device. Axes of the radial hydraulic channel and the jet device are perpendicular. Fixation of the whipstock for gas-liquid flow in the flow string collar may be implemented by equipping the flow string collar with an inner groove and the whipstock for gas-liquid flow with a ring holder.

EFFECT: usage of device allows reducing pressure of annular gas notwithstanding temperature and pressure conditions thus increasing life between overhauls for the sucker-rod pumping equipment; besides, this device allows reducing pump-setting depth for the sucker-rod pump due to increase of fluid level over the pump thus reducing consumption of the flow string and pump rods and increasing life between overhauls for the units.

3 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: according to the method the hydraulic fracturing of formation is performed. After hydraulic fracturing of the formation in the well the proppant underflash is left. From above in addition from the coarse fraction proppant the bridge with a rated length is created. This length is selected in view of the condition of providing of counter-pressure on the proppant in the hydraulic fracturing crack sufficient for holding of proppant in a hydraulic fracturing crack at decrease of liquid level in the well down to the well bottomhole level. The package of downhole pumping equipment includes the antisand filter. During the well operation the antisand filter is placed directly over the proppant bridge. The liquid is sampled. The liquid level during liquid sampling - operation is maintained at the level of the deep-well pump.

EFFECT: increase in oil production.

1 ex

FIELD: oil and gas industry.

SUBSTANCE: steam-gas generator for production of oil and gas condensate comprises a closed cabin with steam-gas generator mounted on the gate connected in series to adapter, tubing head, adapter and casing head of the injecting well at the deposit. Besides the generator comprises gas turbine with ejector and regenerator, piston-type compressor, electric board and electric generator coupled to gas turbine. At that the closed cabin with a door and lifting eyes comprises radiator and blower with electric motor in order to cool cooling fluid in combustion chamber of the steam-gas generator, supports with retractable rods for mounting at concrete base, water and fuel tanks placed at the cabin walls, gate couple at one side to piston-type compressor and on the other side to regenerator air duct, gas turbine placed at the cabin roof. The steam-gas generator comprises combustion chamber complete with a jacket for recirculation of cooling fluid in space between walls, with a cover and inlet valve for compressed air heated in the regenerator up to temperature of 600-700C, outlet valve for discharge of exhaust gas to ejector and gas turbine with outlet pipe connected to inlet pipe of the regenerator or to outlet valve with tube. At that the valve gear includes a cylinder with valve piston and spring having a channel for inlet under the valve piston of compressed air from receiver equipped with return valve coupled to the piston-type compressor. Cylinder has openings for discharge of combustion products into circular cylindrical channel with nozzles installed there for injection of water and generation of stream-gas mixture. The combined nozzle comprises a body with tubes to deliver electrically conducting fluid, which are connected to cylindrical channels placed inside the body in the layer of electrically insulating material in parallel to fuel nozzle; at one side of the tubes there are electrodes connected to pulse generator and on the other side there nozzles directed at angle towards each other and interconnected by blasting chamber of the nozzle with orifice. At that regenerator for compressed air heating is made with start-up fuel nozzle, blower and electric motor.

EFFECT: increased oil recovery of the deposit reservoirs.

6 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: inventions group refers to methods and systems for hydrocarbons, hydrogen and/or other products production from various underground formations. Method of underground formation heating is means that melted salt is injected in first channel of pipe-in-pipe heater at first place. At that the melted salt injection to the first channel includes the melted salt injection in the internal pipe of the pipe-in-pipe heater, and melted salt passes through the flow switch to re-direct the flow from the internal pipe to the ring are between the internal and external pipes. The melted salt passes through the pipe-in-pipe heater in the formation to the second place at distance from the first place, at that during the melted salt passage through the pipe-in-pipe heater the heat is transferred from the melted salt to the treated area. The melted salt is removed from the pipe-in-pipe heart at specified second place.

EFFECT: higher efficiency of formation heating.

21 cl, 1 tbl, 12 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is related to oil and gas industries and may be used during development and operation of deposits in the area of permafrost formations. Device for thermal stabilisation at wellhead area includes an aggregate of heat stabilisers placed around the well and connected through the common collector in the upper part with a condenser. At that the lower part of heat stabilisers is also united by the common collector, and finned surface factor and the area of unfinned condenser surface are selected in order to meet performance of the specified mathematical expression.

EFFECT: provision of unconstrained operation and repair of the well at effective stabilisation of thermal state in the wellhead area in permafrost formations.

2 cl, 1 tbl, 2 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: set of inventions relates to extraction of products from underground beds. Proposed method of underground bed heating comprises heat feed from multiple heaters to one section of underground bed by heat carrier fluid circulation via at least one pipeline in at least one heater. Note here that a part of said pipeline of said heater can displace relative to well mouth with appropriate heater using at least one or more sliding seals in said well mouth to compensate for pipeline thermal expansion.

EFFECT: higher efficiency of bed heating.

19 cl, 1 tbl, 24 dwg

FIELD: mining.

SUBSTANCE: cooling fluid medium is fed through the annular space formed between the operational flow column and the final casing string communicating with the fluid medium with the collector. The cooling fluid medium is mixed with the fluid medium of the collector and the fluid media are obtained through the operational flow column. The temperature of the produced fluid media is regulated or reduced by heat exchanging with the cooling fluid medium fed through the annular space to prevent excessive heat dissipation into the geological layer.

EFFECT: improving the efficiency of thermal protection of the layer and controlling the temperature of the fluid media.

20 cl, 1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: invention can be used at exploration of northern deposits and at control over heat-isolation capacity of well structure, contact of permafrost strata thawing halos at adjacent wells of developed deposit cluster. Thermal and physical conditions at wells are determined at two adjacent walls with subsiding permafrost strata that can cause problems at their thawing. Note here that thermometer instruments are arranged in every well behind the outer case strings for temperature measurement in well string space nearby permafrost stratum and at wellhead for fluid temperature registration inside every well at first and second time moments for every well. Said time moments are counted down from the start of well operation to start of permafrost stratum thawing there around. Measures temperatures and time of thawing start are introduced into expressions used to define the empirical factor dependent on stratum heat conductivity. Rime-variable radii of thawing zones and width of through thawed fracture are compared with their actual values measured at gas penetration to forecast the well conditions.

EFFECT: intensified oil production.

1 tbl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is related to submerged wellhead valves passing flow of hydrocarbons from an oil and/or gas well. The submerged wellhead valve has an inner channel for passing extracted hydrocarbons, an inlet port and an outlet port. The inlet and outlet ports are placed at the ends of the inlet and outlet channels respectively and intended for connection to the cooling fluid. At that the above inlet and outlet channels come to the above device to the area suitable for cooling of components heated by warm flow of hydrocarbons.

EFFECT: levelling down requirements to submerged wellhead equipment in regard to mechanical stability in combination with high temperatures resistance, thus excluding use of expensive components.

2 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: invention is related to the field of oil and gas industry, mainly to production of viscous and superviscous oil, and it may be used for production stimulation of oil with viscous components and deposits. High-frequency impulse current is generated by a group HF surge-current generators in a group of twin-transmission power lines in a group of wells and consisting of two isolated conductors or one isolated conductor and used as the second metal conductor of pipelines in the group of wells. The impact is made by an electromagnetic high-frequency pulsed field generated by high-frequency impulse current of conductors in the groups of twin-transmission power lines to the metal surface of pipelines in the group of wells. Thermal and acoustic impact is made on intratubal liquid in the well group and through it on the oil deposit by heating and mechanical vibration of the pipeline metal which occurs at passage of high-frequency impulse current through the twin-transmission power line. Additional thermal and acoustic impact is made on intratubal liquid in the well group and through it on the oil deposit by heating and pressure fluctuations which occur at the end of the twin-transmission power line in result of high-frequency impulse charge through intratubal liquid. At that the HF surge-current generators are set so that they generate high-frequency current pulses with identical pulse length and repetition.

EFFECT: increase of oil production stimulation.

22 cl, 3 dwg

FIELD: physics, atomic power.

SUBSTANCE: invention relates to systems and methods of treating a subsurface formation. An in situ heat treatment system for extracting hydrocarbons from a subsurface formation comprises a self-regulating nuclear reactor; a system of pipes at least partly lying in the core of the self-regulating nuclear reactor with a first heat carrier which circulates through the system of pipes and a heat exchanger. The heat exchanger is designed to allow the first heat carrier to pass through it in order to heat a second heat carrier. The second heat carrier is designed to raise the temperature of at least part of the formation to a point higher than the temperature which enables to form a mobile fluid, light cracking and/or pyrolysis of hydrocarbon-containing material, resulting in formation, in the subsurface formation, of mobile fluids, fluids that are a result of light cracking and/or fluids that are a result of pyrolysis. The influx of heat into at least part of the formation over time at least approximately correlates with the decay rate of the self-regulating nuclear reactor.

EFFECT: high efficiency of formation heating.

19 cl, 8 dwg

FIELD: physics, atomic power.

SUBSTANCE: group of inventions relates to methods and systems for extracting hydrocarbons, hydrogen and/or other products from different subsurface formations. The in situ heat treatment system for extracting hydrocarbons from a subsurface formation comprises a self-regulating nuclear reactor, a pipe at least partly situated in the core of the self-regulating nuclear reactor, having a first heat-transfer medium which circulates through the pipe, and a heat exchanger through which said first heat-transfer medium flows and heats a second heat-transfer medium. The second heat-transfer medium is used to raise the temperature of at least part of the formation to a point higher than the temperature which facilitates fluid mobilisation, light cracking and/or pyrolysis of hydrocarbon-containing material in order to form mobile fluids, light cracking fluids and/or pyrolysis fluids in the formation. The self-regulating nuclear reactor is configured to regulate its temperature by controlling pressure of hydrogen fed into it. Said pressure is controlled based on formation conditions.

EFFECT: reduced amount of energy required to extract products from subsurface formations.

10 cl, 8 dwg

FIELD: mining industry.

SUBSTANCE: method includes mounting of packing element at lower limit of upper portion of thermo-isolated tubing pipe. Circulation pipe, performing a function of heat-exchange contour, with diesel fuel as heat carrier and following heat exhaust into atmosphere, is connected at whole length to upper portion of tubing string. Their lowering into well and support on the mouth is performed with displacement of tubing string axis relatively to well axis. Upper end of circulation pipe in summer period is connected to forcing line of heat-exchange plant, in winter period to forcing line of cooling plant. Forced circulation of diesel fuel is performed in upper portion of operation column through circulation pipes with following ascent along ring-shaped space. Mathematical formulae for calculating depth of packing element mounting, circulation pipe diameter, tubing string displacement value and diesel fuel flow are provided.

EFFECT: higher efficiency.

1 dwg

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