RU2781311C1 - Method for monitoring producing horizontal boreholes - Google Patents

Abstract

FIELD: petroleum industry.

SUBSTANCE: invention relates to the field of petroleum and gas industry, in particular, to the field of operation of horizontal boreholes, and can be used in the development of petroleum, gas, and gas condensate fields. The method includes using tracer tags characterising the operation of the borehole, followed by analysing the contents of the tracer tags in the borehole fluid. In the implemention of the method, at least one chamber containing tracer tags is temporarily installed along the length of the borehole during operation in the flow of borehole fluid, configured to be removed and/or moved in the borehole, said being suitable for isolation into the surrounding borehole fluid in order to determine the interval inflow and phase composition of the borehole fluid.

EFFECT: possibility of obtaining qualitative and quantitative information on the inflow of fluids from various intervals of the layer.

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Description

The invention relates to the field of oil and gas industry, in particular to the field of operation of horizontal wells, and can be used in the development of oil, gas and gas condensate fields.

Known (RU, patent 2171888, publ. 10.08.2001) method for monitoring the tightness of the annulus. According to the known method, a cement slurry with gaseous chemically inert radioisotopes is injected behind the casing string of pipes, background gamma ray logging is carried out after the formation of cement stone and gamma ray logging after specified periods of time with the determination of the moment of the start of behind-the-casing flow based on the results of comparison of control gamma ray logging with background, moreover, as a radioisotope, a long-lived gaseous chemically inert radioisotope with monochromatic gamma radiation is used, which does not have short-lived decay products that are injected directly into the cement slurry. It is generally recommended to use the radioisotope krypton-85, which has a half-life of 10.71 years, having monochromatic gamma radiation of 0.5 MeV, in the absence of short-lived decay products.

Known (SU, author's certificate 977726, publ. 11/30/1982) method of monitoring the development of oil and gas fields. According to the known method, a labeling agent is used for control, previously introduced into the body of a productive formation, and at least one fluorocarbon compound is used as a labeling agent. For its qualitative and quantitative determination in well production, the method of nuclear magnetic resonance is used.

Known (RU, patent 2544923, publ. 20.01.20016) is a method for monitoring the production of fluid in a well passing from the surface of the earth into the reservoir. According to this method, a cartridge well filter is installed in the well, including the first end, the second end opposite the first end, the cylindrical wall, including the inner surface forming the inner space of the well filter, open from the first end to the second end, and the outer surface, an opening passing through the cylindrical wall to create access from the outer surface to the internal space, a fluid filtering material for filtering that excludes the passage of oversized particles through the hole, a fluid tracer material movable in the downhole filter and located on an installation site spaced from the hole, passing to the inner space, and outside of the inner space, and the mounting platform is located so that the fluid flow path is limited by the limits of passage from the mounting platform along the outer surface and through the opening before entering the inner space space, allow the fluid flow to pass past the fluid tracer material on the outer surface and through the opening into the inner space, wherein the fluid captures the tracer from the fluid tracer material, ensure the movement of the fluid through the inner space to the surface, and monitor the fluid entering on the surface, for the presence of a tracer.

Known (RU, patent 2702042, publ. 03.10.2016) is a method for quantifying the inflow profile in low- and medium-rate horizontal oil wells with multiple hydraulic fracturing, which consists in implementing the thermoconductive principle of measuring the flow rate using artificial heating of a fiber-optic sensing element, and heating and the temperature measurement is carried out simultaneously within the local zones or the entire length of the distributed fiber optic measuring system located in the wellbore in the investigated depth interval.

Also known (RU, patent 2735795, publ. 09.11.2020) is a method for determining interval fluid inflow in oil and gas wells, including the use of sources of fluid temperature changes distributed inside the well and sensors for measuring changes in this temperature, which determine the characteristics of the formation fluid inflow, and before starting measurements are performed to shut down the well, after which the fluid temperature is changed by creating a thermal mark using a heater in the form of a heating cable winding located on axisymmetric mandrel in working areas, and a distributed temperature sensor in the form of an optical fiber located on axisymmetric mandrel between the heating cable rings or rings located after the heating cable, and then, after a time interval sufficient for the appearance of heat marks in this working area, the well is started, after which the speed of movement of the created heat marks in the wellbore is measured to determine the flow rate in various working zones of fluid inflow is determined by the speed of movement of the indicated marks and the previously known diameter of the well pipe, and the result obtained in the nearest working zone with the maximum flow rate before the wellhead is taken as the well flow rate.

The disadvantage of these methods is the use of additional equipment, which makes it difficult to descend into the well.

The technical problem solved by the implementation of the developed method is to provide the possibility of profiling the well fluid inflow in the operating mode of the well without distorting the inflow profile pattern without requiring stops for sampling by using equipment lowered into the well during its operation, while the equipment used contains marker ( tracer) substances that are released into the well fluid in one way or another.

The technical result achieved by implementing the developed method is to provide the possibility of obtaining qualitative and quantitative information about the influx of fluids from different reservoir intervals.

To achieve this technical result, it is proposed to use the developed method for monitoring production horizontal wells. According to the developed method, tracer-markers characterizing the operation of the well are used, followed by analysis of the content of tracer-markers in the well fluid, and along the length of the well during its operation, at least , one chamber with tracer-markers placed in the chamber with different unique properties suitable for isolation into the surrounding well fluid in one way or another to determine the interval inflow and phase composition of the well fluid.

In some embodiments of the developed method, marker chambers are mounted on tubing pipes.

At the same time, tracer tags can be installed with the possibility of being released upon contact with water, oil or gas and/or upon exposure to an external control signal.

In other embodiments of the developed method, marker cameras can be installed on a logging cable that is lowered into the well into the inner part of the production string, with the possibility of releasing tracer marks upon contact with water, oil or gas and/or from an external control signal.

In other embodiments of the developed method, marker cameras can be installed on a geophysical cable lowered into the well into the internal cavity of the tubing, when the well is operated by a gas lift method of operation, with the possibility of releasing tracer marks upon contact with water, oil or gas and / or from an external control signal.

In some embodiments of the developed method, the marker chambers are set for a certain information collection time: the release time can be controlled both autonomously upon contact with water, oil or gas, and from an external control signal.

Marker chambers can be used as part of an assembly with insulating downhole elements (packers, cup packers, etc.)

In the basic version, the developed method is implemented as follows. Marker chambers are lowered into the well to be monitored in the process of its operation on tubing or on a geophysical cable, inside which tracers-marks for detecting hydrocarbons and tracers-marks for detecting water are placed by any known method.

The required number of marker cameras for monitoring individual intervals of a larger or smaller part of the well is used.

Marker chambers are placed opposite the inflow intervals that need to be monitored. In this case, a means for detecting tracers-marks of both types is placed at the well outlet. By controlling the relative content of both types of tracers, the inflow profile and the phase composition of the well fluid are determined. With a sharp increase in tracer marks for detecting water, water breakthrough into the well is determined and a well-known set of measures is taken to eliminate the breakthrough. With a sharp increase in tracer marks for gas detection, an undesirable interval of gas breakthrough is revealed and a well-known set of measures is taken to eliminate it.

An example of the implementation of the method is the following. After the engineering calculation, the tubing assembly is lowered into the well on a hanging packer, on which marker chambers containing tracers for oil, water and gas are mounted. Marker cameras are placed opposite the perforation intervals of the oil and gas formation. The intervals where the marker chambers are set can be isolated with cup packers, for example. Further, downhole pumping equipment is lowered into the well and the well is put into operation. During operation, as the fluid flow passes through the marker chambers, the tracer substances are washed out and carried to the wellhead. Liquid samples are taken from the surface. As a result of the analysis of fluid samples, the concentration of tracer marks determines the influx of oil, water and gas in the intervals of installation of the cameras.

Another implementation example. After the engineering calculation, the tubing assembly with downhole pumping equipment is lowered into the well. At the end of the pump, using a geophysical cable, marker chambers containing tracer substances are suspended opposite the perforation intervals of the oil and gas reservoir. During operation, as the fluid flow passes through the marker chambers, the tracer substances are washed out and carried to the wellhead, where they are analyzed. As a result of the analysis, the influx of oil, water and gas is determined in the intervals of installation of the cameras.

Another implementation example. Marker chambers can be opened and injected into the surrounding well fluid using a signal from an external control device coming through the geophysical cable, thus surveys can be carried out at any time necessary. When operating a well without the need for surveys, the marker chambers are in the closed position.

Another implementation example. After the engineering calculation, the tubing assembly is lowered into the well on a hanging packer, on which marker chambers containing marker (tracer) substances are mounted to detect oil, water and gas. Marker cameras are placed opposite the perforation intervals of the oil and gas formation. Further, downhole pumping equipment is lowered into the well and the well is put into operation.

The marker chambers can be opened and closed using a signal from a control device mounted with the marker chamber. The control device has a battery and a control unit. The signal to open and close is programmed before the device is lowered into the well.

During operation, as the fluid flow passes through the open marker chambers, the tracer substances are washed out and carried to the wellhead, where they are analyzed. As a result of the analysis, the inflow of oil, water and gas is determined. If the marker chambers are closed, the tracer substances are not washed out.

Another implementation example. When the well is operated by the gas-lift method of operation, marker chambers containing tracer substances for oil, water and gas are lowered into the internal cavity of the tubing on a geophysical cable. Marker cameras are placed opposite the perforation intervals of the oil and gas formation.

Marker chambers can be opened and closed using a signal from an external control device coming through the geophysical cable, thus surveys can be carried out at any time required. When operating a well without the need for surveys, the marker chambers are in the closed position.

During operation, as the fluid flow passes through the marker chambers, the tracer substances are washed out and carried to the wellhead, where they are analyzed. As a result of the analysis, the inflow of oil, water and gas is determined.

Claims (3)

1. A method for monitoring producing horizontal wells, including the use of tracer marks characterizing the operation of the well, followed by analysis of the content of tracer marks in the well fluid, characterized in that along the length of the well during its operation, the flow of the well fluid is temporarily with the possibility of removal and / or moving along the well, at least one flow chamber is installed with tracers-markers placed in the flow chamber, suitable for isolation into the surrounding well fluid to determine the interval inflow and phase composition of the well fluid, each flow chamber being placed against the formation length interval that needs to be controlled , while the flow chambers are used as part of the assembly with insulating downhole elements. 2. The method according to p. 1, characterized in that the flow chamber is mounted on the tubing. 3. The method according to p. 1, characterized in that the tracers-tags are installed with the possibility of release when exposed to an external control signal.