RU164347U1 - DEVICE WITH INDICATOR IN AN AMPOULE FOR TRACER RESEARCH OF HORIZONTAL WELL WITH SEPARATED INTERVAL PACKERS AND INTERMEDIATE HYDRAULIC BREAKING - Google Patents

Abstract

1. Device for tracer research of a horizontal well with packers separated by intervals of interval hydraulic fracturing, comprising a container with an indicator, characterized in that it is arranged to be placed on the outer wall of the casing of the well in the bottomhole zone of the well interval and introduce the indicator into the wellbore zone wells and made in the form of a container containing a housing with means for attaching it to the outer wall of the casing of the well, an external protective a casing and at least one chamber with an indicator in a pressure-breakable ampoule and openings and channels for entering the chamber with a formation fluid indicator and exiting formation fluid with an indicator into the bottom-hole zone of the well interval. 2. The device according to claim 1, characterized in that it contains an indicator in an ampoule that is destroyed by hydraulic fracturing pressure. 3. The device according to claim 1, characterized in that the holes and channels for entering the chamber with the formation fluid indicator and exiting the formation fluid with the indicator are calibrated. 4. The device according to claim 1, characterized in that the openings and channels for entering the chamber with the formation fluid indicator and out of the formation fluid with the indicator comprise means for controlling the amount of formation fluid entering the chamber with the indicator and / or the amount of formation fluid exiting from it indicator, made, for example, in the form of fittings or valves for regulating the amount of formation fluid entering the chamber with an indicator and / or the amount of outgoing formation fluid with an indicator. 5. The device according to claim 1, characterized in that

Description

Technical field

The utility model relates to the mining oil industry, to geophysical exploration of horizontal wells at intervals separated by packers and with interval hydraulic fracturing, and can be used to monitor the development of oil and gas fields using horizontal wells in oil reservoirs.

State of the art

One of the main tasks of the oil industry is to increase the efficiency of oil reservoir production and increase oil recovery of producing wells.

Hydraulic fracturing (hydraulic fracturing) is a common method of intensifying the work of oil and gas wells.

Hydraulic fracturing is one of the most complex and expensive types of work in the oil and gas industry. Due to the high cost of hydraulic fracturing, the issues of determining the parameters of hydraulic fractures formed are of great practical importance from the point of view of controlling the process of formation of fractures, evaluating the productivity of individual intervals (sections) of a horizontal well and the success of hydraulic fracturing.

One of the modern best practices in the oil industry is the multi-zone fracturing method, the most effective for horizontal wells.

In particular, in 2013-2015, LUKOIL plans to drill 449 horizontal wells, followed by the use of multi-zone hydraulic fracturing. The application of this technology has shown high efficiency in fields with hard-to-recover reserves in Western Siberia [http://www.rogtecmagazine.com/PDF/lssue_031/04_Multi Zone Hydro Fracturing at Lukoil.pdf].

The horizontal trunk for this is equipped with special annular swellable packers that divide the trunk into separate intervals (sections). In each interval, devices are installed that provide access for hydraulic fracturing (hydraulic fracturing ports) through which subsequent production of well fluid or gas is usually carried out by means of production and injection wells.

To optimize the relative position and operating modes of production and injection wells, it is necessary to have reliable information about the intensity of formation fluid input into one or another interval of the horizontal wellbore. This information allows you to clarify the hydrodynamic model of the oil reservoir and optimize oil production.

Reliable information on the movement of reservoir fluids is particularly important in the case of oil production in low-production horizontal wells with interval hydraulic fracturing.

In addition to the heterogeneity of the properties of the oil reservoir, which can be known from geophysical studies, in the production process there is heterogeneity of the filtration properties of the reservoir associated with the volume and composition of the reservoir fluid, and, accordingly, different performance of the horizontal ports located at different intervals of individual ports.

Between injection and production wells can also arise channels filled with water (having a low viscosity), through which the injected water enters the production well and does not provide oil displacement.

When developing a field using wells with horizontal completion, information is needed on which interval and through which port of the horizontal well the main flow of injection water and well fluid occurs.

For these reasons, the development of research methods and control of the movement of reservoir fluids in an oil reservoir developed using hydraulic fracturing in multi-interval horizontal wells is of great practical interest.

The flow of the borehole fluid along the horizontal section of the borehole is usually accompanied by the separation of the fluid into phases (gas, oil and water). Each of the phases is significantly different from the other rheological properties, as a result of which all phases move in the well at different speeds, the formation of stagnant zones of water in the lower part and gas caps in the upper part.

In this regard, reliable quantitative determination of fluid inflow (flow measurement) in each individual interval of the well with a horizontal end and determination of the phase ratio (water / hydrocarbons) coming from the reservoir into each interval of the well are relevant.

Known technologies for oil production using tracer methods for monitoring and studying fracture parameters during multi-stage fracturing. Tracer research methods are the most direct and accessible methods for obtaining reliable information.

The tracer methods for studying the reservoirs are based on the use of data on the movement of indicators (indicator reagents, tracers, tracing agents) together with the carrier fluid, taking into account the filtration-capacitive parameters of productive deposits, changes in reservoir and bottomhole pressures.

However, in the well-known tracer methods for studying reservoirs, indicators, along with injection fluid, are usually introduced into the formation through injection wells, pass with injection fluid through the formation into the bottom-hole zone of the producing well, are selected through the appropriate ports and analyzed as part of the well fluid taken from the producing well.

There is a method of studying the movement of oil in the reservoir during the development of a reservoir, which consists in introducing into the reservoir through injection wells an indicator with a carrier, according to which separate fractions of oil selected from the reservoir are used as a carrier, and tritium or fluorine is used as an indicator (SU 1017794 E21B 47 / 00, published in BV No. 18, 1983).

There is a method of studying the movement of oil in the reservoir during the development of a reservoir, which consists in simultaneously injecting several different indicators into several injection wells together with a carrier, namely industrial water, into one of the injection wells, moreover, one indicator is pumped into each of the injection wells, and in the flows, coming out of production wells separately record the content of all used indicators and control the movement of oil in water by the time of their passage (see Wagner OR Journal of Petroleum Technology, 1977, N 11, p. 1410-1416).

A known method of hydrodynamic research of horizontal wells in real time, which to obtain real-time information about the properties of the productivity of a horizontal wellbore in real time during the operation of a well includes exciting the well, measuring parameters using downhole instruments installed inside perforated tubing in horizontal sections of the well with various geophysical characteristics, and processing of measurement results. As deep instruments, remote instruments are used, interconnected by a geophysical cable, using a lead-in sub, the geophysical cable is led out of the tubing string into the annulus. A downhole pump is installed in the vertical part of the well and, at the same time as the geophysical cable is lowered, the downhole pumping equipment is lowered. In this case, the geophysical cable is fixed on the tubing string with bands, to the surface the cable is led out through the technological hole in the pipe holder, where it is sealed and connected to the ground-based registration unit [RU 2483212 E21B 47/00 Publ. 05/27/2013]

The disadvantage of the method according to RU 2483212 is the inability to measure the flow rate of individual phases of the multiphase flow of a horizontal well.

A known method of researching a horizontal well, which, in order to obtain reliable information for constructing a quantitative injectivity profile of productive intervals of “hot” horizontal wells, involves the descent of the tubing string into the well and pumping the working agent into the pipes with a measurement of its flow rate and injection pressure at the wellhead. Before lowering the tubing, the packer is assembled with a multi-action packer with a liner, and when lowering the tubing, the packer is installed above the roof of the first production interval in the direction of drilling the well. The injection pressure of the working agent is fixed at the wellhead after it is stabilized, then the packer is disrupted and the tubing is further lowered, followed by the packer installed over the roof of the next productive interval during the course of the well drilling. Then, the working agent is again injected, and after stabilization of the wellhead injection pressure, it is maintained equal to the injection pressure of the working agent in the previous study and the flow rate of the working agent is also fixed, while the packer is stalled, the tubing is lowered and the packer is installed above the roofs of the productive intervals repeatedly depending on the number of productive intervals, and the injection pressure of the working agent during each study is maintained at the wellhead nym equal to the discharge pressure of working agent when installing a packer above the roof of the first production interval in the course of drilling, then on the basis of recorded operating costs agent determines the number of working agent absorbed by each production interval in a unit time [RU 2515641 E21B 47/00 Publ. 05/20/2014].

There is a known method of researching reservoirs, in which to increase the efficiency of work when developing oil deposits to increase oil recovery, water is pumped through injection wells, production is taken through production wells, primary tracer studies are used to identify filtration channels connecting injection wells to production wells, with their subsequent blockage insulating material, and continued injection of water into injection wells. Moreover, in addition to the flow diverting compositions and solutions of chemical reagents forming the insulating material, a tracer agent compatible with them is introduced that is different from that used for primary tracer studies. Based on the results of monitoring the composition of the produced products from the producing wells and the content of tracing agents in it, the direction of the flow diverting compositions and solutions of chemical reagents, the effectiveness of the impact on the formation and the stability of the insulating material over time are determined. Sedimentary compositions, crosslinked polymer systems, oil-water emulsions, polymer solutions with controlled gelation time, and reagents that create an insulating material by interacting with formation water are used as flow-deflecting compositions and solutions of chemical reagents. [RU 2398962 E21B 47/10, E21B 43/20 Publ. 09/10/2010].

There is a method of monitoring the geometrical and hydrodynamic parameters of hydraulic fracturing, according to which to control the geometrical and hydrodynamic parameters of hydraulic fracturing with the possibility of obtaining reliable hydrodynamic characteristics resulting from hydraulic fracturing of fracture systems, and simplifying the generation of their model in space, they carry out surface radon imaging, radon indicator research, measurement of gamma activity by a borehole gamma-gamma-defectometer-thickness gauge (SGDT), while surface radon survey is carried out prior to hydraulic fracturing in a square of 400 × 400 m, in increments of 50 m, radon indicator studies are performed to obtain such hydrodynamic characteristics of the formation as permeability and injectivity profile, gamma activity is measured by the SGDT instrument hydraulic fracturing, repeat radon survey, radon indicator studies, measurement of gamma activity with the help of the SGDT device, the obtained data is compared and the azimuthal location of hydraulic fractures is established, as well as the permeability and injectivity profile of the formation [RU 2390805 G01V 5/12 Publ. 05/27/2010].

There is a method of research and development of a multilayer hydrocarbon field in the development of an oil reservoir with a porous-fractured reservoir, according to which, to increase the information content of the studied reservoirs of the development object and optimization of the reservoir pressure field, a tracer agent of the required concentration is pumped together with the displacing agent at the wellhead pressure and record its concentration in production wells. For this, an individual tracer is pumped into each of the layers of at least one injection well at a given bottomhole pressure, and its concentration in production wells is recorded at the outlet of the corresponding formation. After that, the basic parameters of each layer are determined - the presence, orientation and volume of cracks (discontinuous faults), the filtration rate along them, their permeability, the volume of unproductively injected water, as well as their hydrodynamic connection with each other. The bottomhole pressure is changed when the tracer is injected for at least one of the injection well reservoirs and this process is continued until the uncertainty in the reservoir parameters is eliminated or until the optimum displacement agent injection pressure is achieved [RU 2315863 E21B 47/10 E21B 43/00 Publ. 01/27/2008].

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, или F′, или I'. Зная, какимиAs a tracing agent in this method, salts are used that are stable under reservoir and barometric conditions and are not adsorbed on the formation rocks, rhodanites (ammonium), sodium fluorescein, rhodamine, alkali metal nitrates (sodium, ammonium), alkali metal sulfates (sodium, potassium), phosphates of alkali metals, as well as radioactive isotopes with predetermined half-lives. As an individual tracing agent, the components of the displacing agent are used, which differ in their properties from the produced and injected water, and which are not adsorbed on the rock. One of the criteria for choosing tracing agents is their low adsorption on the rock, dissociability. The concentration of cations and / or anions is recorded in water - Na ^- or Ca ^- , or Mg ^- , or K ^- , or Li ^- , or Sr ^- , or Ba ^- , or V ^--- , or Mn ^- or Fe ^- , or Ba ^- , or

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The components of the injected water are different from the formation water, their ratio or the ratio of specially created groups is analyzed, and the origin of the water in the produced products is revealed.

A known method for studying the productivity of sections and ports of a horizontal wellbore is a method for studying liquid-phase dynamic processes in formations with abnormally low pressure [RU 2164599, E21B 47/00, E21B 47/10 Publ. 03/27/2001], according to which indicators of several colors are used to increase the reliability of studies by choosing the indicator properties, and the indicator of each color is obtained in the form of a liquid suspension of microgranules consisting of a mixture of a polycondensation resin and an organic luminescent substance. The degree of dispersion of the microgranules is determined by the proposed formula. The indicators are mixed with the selected volume of reservoir fluid in a predetermined ratio. The centrally located injection wells are selected in a specific manner. The suspension of the indicator of the same color is pumped into each of them. The proposed formula determines the time after which the first sample is taken from each observation well. Also, the proposed formulas determine the frequency of sampling of the reservoir fluid and the time of completion of sampling. In each sample taken, the concentration of the indicator of each color is determined. According to the proposed formula, the corresponding concentration of a similar indicator entering the bottomhole formation zone corresponds to it. By the found set of values of the change in the concentration of the indicator of each color over time in the bottom-hole zone of the formation, its capacitive-filtration properties and the direction of liquid-phase flows are determined.

In the preparation of indicator microgranules according to this prototype method, a polycondensation resin (melamine formaldehyde resin or melamine urea formaldehyde resin) is used (the action is identical), which is mixed with acetone and an organic luminescent substance: fluorescein (green indicator) or rhodamine B (other red indicator) indicators of blue and yellow in the ratio of wt. hours, equal to 1: 1: 0.1, respectively, until a homogeneous mass is formed, which cures within 24 hours. The resulting solid mass is ground in a ball mill (LE-101.1 Hungary) and sieved to a fraction of not more than 2 mm. The powder is mixed with solutions of ammonia and anionic surfactant brand Crystal in the ratio of wt. hours equal to 1: 0.6: 0.05, respectively. Next, grinding is done on a ball mill (LE-101.1 Hungary) to the calculated degree of dispersion.

Then the suspension of the indicator in an amount of 0.007 m ^{3 is} mixed with 7 m ^{3 of} produced water, realizing the ratio of vol. hours equal to 0.001 - 1, respectively.

Using a cement-mixing unit CA-320M, the obtained suspension of the indicator with the reservoir fluid, volume 7.007 m ³ , is pumped through the injection well into the reservoir. The starting concentration of the indicator is 10 ¹³ microgranules / m ³ .

Water samples are taken from the level of the wellbore fluid using the GGP-20 bailer from observation wells. The content of the indicator is determined in the selected water samples by filtering the sample through a fine-porous Vladipor filter with a pore diameter of 0.4 μm. On a fine-porous filter, the microgranules of the indicator of each color are quantified using a Lumam-P2 luminescent microscope.

The indicator is identified by five parameters: 1) the color of the microgranules, 2) the shape of the microgranules, 3) the nature of the surface of the microgranules, 4) the intensity of the glow, 5) the size of the microgranules.

In the most difficult cases, according to the method of RU 2164599, quantitative fluorimetry is used, realized using a fluorescence-microscopic fit FMEL-1A, and an FEU-79 photomultiplier with a set of light filters SS 15, KS 11, OS 11, NS 10, ZS 12 is used as a spectrum analyzer , ZS 1, UFS 6-3, UFS 6-5, FS 1-1, FS 1-2, FS 1-4, FS 1-6, SS 15-2, SS 15-4, SZS 24-4, SZS 21-2. An SVDSh-250 mercury lamp is used as a source of ultraviolet radiation.

By the values of the indicator concentrations in water samples taken from the level of the wellbore fluid, the indicator concentrations corresponding to them, previously received in the bottomhole formation zone, are determined.

A common drawback of the methods described above is the inability to determine the parameters of certain sections (intervals) of the horizontal production well through which the main flow of produced products takes place, as well as the inability to determine the ratio of the water / oil phases from different intervals of the horizontal well.

The well-known methods of tracer studies described above are aimed at obtaining information about the movement of fluid through the reservoir from the injection well to the producing one, but not one of the methods does not solve the problem of reliably determining the productivity of specific sections (ports, intervals) of the horizontal well of the producing well and the operations of individual hydraulic fracturing in specific separated by packers intervals of horizontal wells.

Known devices for the study of horizontal wells using flowmeters of various designs, which are technically complex, require the use of expensive operations to lower / raise pumping equipment from the well, stop the operation of the well and have insufficient reliability of the results.

Known methods and devices of field-geophysical (PIP) in horizontal wells using instruments with several flowmeters at different flow levels, according to which the instruments are lowered using coiled tubing based on the use of flexible continuous pipes that are pushed into the well and replace traditional prefabricated drill pipes works inside the wells [https://ru.wikipedia.org/wiki/%D0%9A%D0%BE%D0%BB%D1%82%D1%8E%D0%B1%D0%B8%D0%BD%D0 % B3].

Coiled tubing can reduce the time of operations for launching geophysical instruments into wells and partially solve the problem of moving instruments in the horizontal part of the trunk, but in itself it is a complex and expensive equipment. The use of several flowmeters at different levels of the flow allows to reduce the measurement error, but does not solve the question of the reliability of measurements completely. In addition, it does not allow to determine the phase ratio of the extracted products.

Such studies of the road, mainly foreign service companies possess the necessary equipment, therefore they are hardly accessible to domestic oil companies.

Currently, various devices are known for monitoring and studying parameters of hydraulic fracturing results based on hydrodynamic studies, seismic-acoustic monitoring, and geophysical methods.

Most geophysical instruments successfully used to study fluid flow rates in vertical and deviated wells are based on the principle of a blade flowmeter. However, the use of such flowmeters in a horizontal shaft is both inefficient and often impossible.

In a horizontal wellbore, the flowmeter blades are washed by a three-phase flow with different speeds of each flow. Thus, the indications of standard geophysical instruments based on the principle of a vane flowmeter are unreliable.

In addition, the descent into the well with a horizontal end of the geophysical instruments on the geophysical cable is either impossible or requires the use of expensive equipment to move the geophysical instrument.

A device for researching wells [Petrov A.I. Measurement methods and techniques for field research of wells. - M .: Nedra, 1972], including a geophysical instrument lowered into a well on a cable (flowmeter, moisture meter, resistivity meter, etc.). When moving the device along the filter part of the well, information is recorded that allows you to determine the intervals of inflow and the composition of the fluid flowing into the wellbore from the formation. The disadvantage of this device is the ability to study only vertical wells and the inability to conduct studies of horizontal and deviated wells.

A device for researching horizontal wells is known (Rapin V.A., Chesnokov V.A., Evdokimov V.I., Lezhankin S.I. New technology for conducting geophysical exploration of horizontal wells, Oil industry, N 9, 1993, p. 14-16), which includes a geophysical instrument, a pusher, and a mover loaded into the well on a logging cable. As a pusher and mover load, standard deep pump rods are used, which are fixed to the logging cable with the help of the upper and lower cable clamps. The length of the pusher is 357 m, and the length of the propulsive load is 167 m, respectively. When conducting research, a geophysical instrument is lowered into the well by cable. Next, the pusher rods are attached to it and, increasing them, are lowered into the well. When all the rods of the pusher and the propulsion load are lowered into the well, the upper end is fixed to the cable using the upper cable clamp. Next, the entire assembly on the cable is lowered into the well. When the geophysical instrument reaches the curved part of the well, under the influence of gravity of the rods of the pusher and the propulsion load, it slides along the bottom wall of the casing, as if on an inclined plane, and passes into a horizontal wellbore. Then, the pusher rods slide behind it and push the geophysical instrument towards the bottom of the well. Research is carried out during the launch of the geophysical instrument through the tubing and the excitation of the well from the compressor. According to the research results, intervals of fluid inflow into the wellbore are distinguished.

This device is inexpensive and not difficult to manufacture, it uses standard deep-sucker rods, however, its significant drawback is the limited length of the studied horizontal trunk, since it can actually be used with a horizontal trunk length of not more than 200 m, and with a longer length, the load on cable during tripping is close to the breaking strength of the cable.

A device for conducting research of horizontal wells is known (Chesnokov V.A., Galin V.A. Improvement of well logging technology in drilled exploited and horizontal wells. Well construction on land and at sea, VNIIOENG, 1995, N 6, pp. 25-27 ), which is a pusher lowered into a well on a wireline cable, made of thin-walled air-filled airtight pipes with current-carrying conductors inside. The length of the pusher is equal to the total length of the horizontal and curved parts of the well. A geophysical instrument is attached to the bottom of the pusher, and a propulsive load is fixed on top of it to the wireline cable. This complete assembly is lowered into the well on a wireline cable. When the curved part of the well is reached, the geophysical instrument, under the action of gravity of the propulsive load and the pusher tubes and due to the rigidity of the latter transferred to the instrument body, begins to slide along the bottom wall of the well, as if on an inclined plane, turning into a horizontal wellbore. Pusher tubes slide behind it, moving the device to the bottom of the well. The device allows you to explore horizontal active wells. Moreover, due to the fact that the pusher is made of air-filled, airtight pipes, the average density of which is close to the density of the fluid filling the well, the force required to push it in the horizontal well is reduced and it is possible to study wells with a horizontal well of 300 m or more.

According to the results of studies conducted using similar geophysical instruments (flow meters, moisture meters, resistivity meters, etc.), the intensity of fluid inflow into the wellbore and its composition are determined.

However, most horizontal wells have a large horizontal wellbore (300 m or more) and a relatively low production rate (average production rate of no more than 10 tons / day of oil).

In this regard, there is a low specific flow rate (fluid inflow per unit length of the filter) and, as a result, the separation of liquids in a horizontal well in density. In this case, oil fills the upper part, and water accumulates in the lower part of the casing string. In addition, there may be stagnant water, which accumulates in low sections of the horizontal trunk at low flow rates.

When conducting research in a horizontal bore with an off-center small-sized device, the latter moves along the bottom wall of the casing. If there is stagnant water in the horizontal shaft, the device will show the presence of water, as in fact there may be an influx of oil over the top of the column. Similarly, the oil flow may not be fixed by a centered small-sized device, because most of the casing can be filled with stagnant water, and oil flows in a thin stream along the upper wall of the casing.

Thus, it is not possible to unambiguously determine the composition of the fluid, and therefore the interval of the horizontal well from which it arrives, using known devices in low-production wells.

Known geophysical instrument, made in the form of a multi-section sampling chamber, the length corresponding to the length of the filter part of the well, in which each section of the chamber has an inlet with a controlled valve and in each section there is an air-filled compartment by which the average density of the fluid-filled chamber is less than the density of the oil pumped out from the well, and the device itself is equipped with removable weighting agents, allowing to increase the average density of the unfilled chamber to values exceeding the flat the density of the water pumped out of the well [RU 2109941 E21B 47/00 Publ. 04/27/1998].

Due to the fact that this geophysical instrument is made in the form of a multi-section sampling chamber, the length corresponding to the length of the filter part of the well, each section of which has an inlet with a controlled valve, it is possible to take fluid samples along the entire length of the horizontal well, which allows you to determine the composition of the fluid at each point of the horizontal trunk.

The implementation in this device of each section of the sampling chamber with an air-filled compartment (through which the average density of the fluid-filled sampling chamber is less than the density of oil pumped out of the well) allows the chamber to float in the horizontal well and the upper wall of the casing and, in the case of oil flow through stagnant water, can determine the interval the influx of oil into the well, and the supply of the device with removable weighting agents, allowing to increase the average density of the unfilled chamber to a value At the same time, it is possible to take samples at the bottom wall of the casing and, accordingly, to determine sections of the horizontal wellbore filled with stagnant water.

This technical solution allows you to determine the composition of the fluid in the horizontal wellbore, i.e. the water content in the oil-water mixture and, accordingly, the depth interval with which it flows into the wellbore, however, the use of this device is associated with significant costs for launching the device using a geophysical elevator, it is not possible to study long horizontal wells, and the device also provides information about the source of water supply, but does not allow to measure the volume of fluid from each interval of the well.

A device for the study of horizontal wells is known, which, to increase the accuracy of measuring the flow rate and composition of the liquid in horizontal low-rate wells, contains a geophysical instrument lowered into the well on a cable with a pusher and mover and is additionally equipped with float elements at the ends of the geophysical instrument, the average density of which together with geophysical instrument less than the density of oil pumped out of the well [RU 2114298 E21B 47/01, E21B 47/00 Publ. 06/27/1998].

The presence of float elements in this geophysical instrument ensures its floating due to the Archimedean force to the upper wall of the casing and, due to the fact that the average density of float elements together with the geophysical instrument is lower than the density of oil pumped out of the well, the geophysical instrument is pressed against the upper wall casing string, regardless of whether this section of the string is filled with water or oil. In this case, the device is in the oil flow and its flow rate (flow rate) and composition (percentage of water) are measured.

This device allows you to place the geophysical instrument directly into the oil stream, which flows through stagnant water with a thin loop along the upper wall of the casing. This provides an increase in the accuracy of measuring the flow rate and composition of the reservoir oil fluid flowing into the wellbore, but it does not allow simultaneously measuring the flow rate and composition of the water fluid

The closest analogue prototype for the proposed device for studying the productivity of sections and ports of a horizontal wellbore is a device for researching horizontal wells containing a jet pump, a packer and a tubing string in a vertical section of a well, characterized in that the jet pump shank is equipped with a pump string -compressor pipes to the bottom with containers for installation of deep autonomous integrated devices placed in a horizontal section [RU 41081 E21 B 49/00 Publ. 10/10/2004].

The prototype device for the study of horizontal pumping wells according to RU 41081 contains a jet pump connected by a tubing string on one side to the wellhead, to which a pump unit is connected via valves, connected to a measuring tank, which is connected through the valve to the annulus of the well. At the other end, the pump is connected by tubing through a packer to a slotted filter, which is connected through the tubing to the other end in series with containers in which complex, stand-alone instruments are installed that record temperature and pressure. The containers are short pipes (1.5-3 m) of the same type of size as the rest of the tubing (1.5 ″, 2.0 ″ or 2.5 ″) with 5-10 openings for communicating the internal cavity pipes with a borehole and plugs on both sides to prevent fluid from moving inside the container.

The prototype device according to RU 41081 works as follows: A tubing string with a jet pump, a packer, a slotted filter and a liner including series-connected containers with integrated devices installed in such a way is lowered into a well cased with pipes and having a horizontal section. to cover the entire horizontal section of the wellbore. The containers are connected to each other by means of one or more tubing, depending on the required distance between the devices. Then equip the wellhead with buffer and annular valves. A pumping unit is connected to the buffer valve, and a measuring tank is connected to the annular valve, which is connected to the unit to ensure fluid circulation, after which the device is ready for well development or pumping oil production with the simultaneous study of the thermohydrodynamic parameters of the reservoir being operated.

The disadvantage of the prototype device according to RU 41081 is the significant cost of running tubing with a jet pump, a packer, a slotted filter, and with a shank that includes containers connected in series with complex devices installed in them. In addition, the use of the device in research requires a shutdown of the well, which inevitably leads to losses in oil production.

Task and technical result

In hydrodynamic studies of horizontal wells, an important task is to determine the productivity and composition of well fluids in individual specific intervals of a horizontal well and to identify useful and / or poorly working intervals of the well, followed by the possible shutdown of badly working intervals of the well and a corresponding increase in well productivity through the use of only well-working intervals.

This problem is of particular relevance when applying to oil production in low-production horizontal wells, as well as when determining the location of new producing wells in a developed productive formation with different water cuts in different intervals of the well.

The flow of a well with a horizontal completion when moving in the horizontal part is usually divided into several phases - gas, water, oil and their mixtures in various combinations and in different proportions in different areas (intervals).

Each phase moves with its own speed and with its volumetric flow rate. In addition, stagnant zones and gas caps are formed at the points of bending of the trunk.

The use of commonly used mechanical flowmeters is technically difficult and inefficient, since their promotion and functioning in the horizontal wellbore is difficult and therefore the known flowmeters do not allow reliable results for individual intervals of the horizontal well.

In this regard, the development of technology and related equipment for reliable determination of the productivity and composition of the borehole fluid of each individual interval (section, port) of a horizontal well is relevant.

The purpose of the utility model is to solve the problem of obtaining reliable information about the productivity (intake of water, oil and their mixtures) of individual intervals of a horizontal well and the ratio of the phases of the well fluid in individual intervals of the horizontal well.

The technical result achieved by using the utility model is

- improving the accuracy of measuring the flow rate and composition of the borehole fluid in various intervals of the horizontal well.

- increase the reliability of the quantitative determination of fluid flow (flow measurement) in individual intervals of the well with a horizontal end (horizontal well).

increasing the reliability of determining the ratio of phases (water / hydrocarbon) coming from the reservoir from individual intervals of the horizontal well

- increasing the reliability of research results by choosing the properties of indicators, allowing to obtain an adequate model that reflects the natural dynamics of liquid-phase flows in various intervals of horizontal wells.

- increasing the efficiency of hydrocarbon field development by making informed decisions based on more complete and reliable information about the studied development object, as well as by optimizing the reservoir pressure field for each of the horizontal well intervals, which ultimately leads to an increase in the hydrocarbon recovery coefficient for the field .

- expanding the range of application of hydraulic fracturing technology by providing the introduction of indicators (tracers) with desired properties with any liquid carrier, including those used with proppant fluids.

Utility Model Disclosure

Typical distinguishing features of the technology, in which it is possible to use the proposed device for the study of individual intervals (sections) of the horizontal wellbore, are:

- the use of various indicators (tracers, tracing agents, tracers, chemical labels, reagent indicators), which can be reliably separately identified and accurately measured in the flow of well fluid in low concentrations;

- the use of various indicators to monitor the movement of fluid from the bottom-hole zones of individual intervals of the horizontal wellbore of the producing well;

- placement of various indicators directly in the bottom-hole zones of individual intervals (ports) of the horizontal wellbore in such a way that each interval corresponds to a unique one, i.e. different from placed at other intervals, indicator.

- analysis of the presence and number of indicators in the composition of the borehole fluid with the determination of the ratio of various indicators brought to the surface by the flow of borehole fluid from the corresponding specific intervals (ports) of the horizontal well;

- calculation and accounting of parameters of well sections, volumes and composition of well fluid from specific intervals (ports) of the well by the amount in the total flow of well fluid corresponding to a specific interval (port) of the quantity of a particular indicator;

- calculation and accounting of water cut and productivity parameters of reservoir sections separated by packers by the ratio of indicators transferred by oil and water;

Typical distinguishing features of the proposed device for studying the productivity of individual intervals of the horizontal wellbore according to the proposed method are:

- the presence in the device of indicators that can be identified and measured in the fluid flow from the well in small concentrations;

- the use of dispensing means (jets, calibrated holes or channels) as part of the device, which allows to regulate the intensity of the output of indicators from the device;

In contrast to the known methods for horizontal well research, the proposed device for studying the parameters and productivity of individual intervals (ports) of a horizontal well with packer intervals and interval hydraulic fracturing, the proposed method and device for its implementation allow:

- with high accuracy to measure the volume of inflow of the well fluid (oil and water) from the individual intervals of the horizontal well;

- obtain reliable information about changes over time in the productivity of well intervals;

- avoid the use of expensive equipment for tripping in the well;

- conduct tracer studies and monitor the productivity of horizontal well intervals without interruptions in the operation of the producing well.

The problem is solved, and the required technical result is achieved by the fact that the device for tracer research of a horizontal well with separate packers at intervals of interval hydraulic fracturing containing a container with an indicator, according to a utility model, is configured to be placed on the outer wall of the casing of the well in the bottomhole zone of the well interval and introducing the indicator into the formation fluid into the bottomhole zone of the well interval and is made in the form of a container containing a body with means of mounting it on the outer wall of the casing string of the well, an external protective casing and at least one chamber with an indicator in a pressure-breakable ampoule and openings and channels for entering the chamber with an indicator of formation fluid and exiting formation fluid with an indicator into the bottomhole zone of the well interval .

In this case, the openings and channels for entering the chamber with the formation fluid indicator and out of the formation fluid with the indicator are calibrated or contain means for regulating the amount of formation fluid entering the chamber with the indicator and / or the amount of formation fluid leaving the chamber with the indicator, made for example in in the form of fittings or valves for regulating the amount of formation fluid entering the chamber with an indicator and / or the amount of outgoing formation fluid with an indicator.

In addition, the device in various versions of the design is made with the possibility of:

- placement on the outer wall of the well casing in the bottom-hole zone of the well interval in the immediate vicinity of the interval port;

- introducing into the bottom-hole zone of the indicator and the ability to determine by the number of indicator in the fluid from the well the effectiveness of hydraulic fracturing in a given interval of the well and the functioning parameters of this interval of the well;

- introducing the indicator into the bottom-hole zone of the well interval and the possibility of determining by the amount of the indicator in the fluid from the well the amount of fluid produced from the given well interval;

- introducing the indicator into the bottom-hole zone of the well interval and the possibility of determining by the amount of the indicator in the liquid from the well the flooding of the liquid produced from the given interval of the well;

- placement on the outer wall of the casing of the well before hydraulic fracturing.

Moreover, as an indicator, the device contains

luminescent and / or fluorescent indicators, for example, microcondensation resin microgranules, for example melamine-formaldehyde resin or melamine-urea-formaldehyde resin, colored with a luminescent substance: green fluorescein or red rhodamine B or other fluorescent substances soluble in formaldehyde;

or oil-soluble or oil-dispersible and water-soluble or water-dispersible indicators with the ability to determine the ratio of water to oil in a liquid from a well interval.

Brief Description of the Drawings

In FIG. 1 shows a view through an eyepiece of a fluorescence microscope of the field of observation of a water filtrate containing fluorescent water-soluble indicators.

In FIG. 2 is a view through an eyepiece of a fluorescence microscope of the field of observation of an oil filtrate containing fluorescent oil-soluble indicators.

In FIG. 3 is a flow chart of the equipment of the well for conducting multi-zone (multi-interval) hydraulic fracturing with an indication of the recommended location for entering indicators and the route of their entry into the well for a variant of introducing indicators into the bottom-hole zone before hydraulic fracturing, which shows: pumping units 1, 2, 3, 4; blender (device for grinding, mixing and preparing the emulsion) 5, manifold block 6; indicator entry point 7; control unit 8; water containers 9, 10; unit CA-320 11; wellhead equipment 12.

In FIG. 4 is a flow chart of the equipment at the well for conducting multi-zone (multi-interval) hydraulic fracturing, indicating the recommended location for entering indicators and the route of their entry into the well for the option of entering indicators into the bottomhole zone during hydraulic fracturing, which shows: pumping units 1, 2, 3, 4 ; blender (device for grinding, mixing and preparing the emulsion) 5, manifold block 6; place of entry of tracers 7; control unit 8; water containers 9, 10; unit CA-320 11; wellhead equipment 12.

In FIG. 5 is a diagram of the application of indicators (tracers) on the surface of the particles of the proppant (proppant), which shows: ceramic proppant 28; water or oil destructible coating with indicators of one of the selected colors 29; indicators 30 entering the well production as a result of dissolution of the proppant coating.

In FIG. 6 is a diagram of a container with an indicator with a possible location of the container on the outer wall of the casing of the horizontal section of the well, where: a flow control fitting 13; indicator (tracer) 14; container body 15; casing (liner) 16 horizontal section of the well.

In FIG. 7 is a diagram of a container with ampoules in the container with an indicator with the location of the container with ampoules with an indicator on the outer wall of the casing of the horizontal section of the well, where it is shown: flow control fitting 17; ampoule with indicator (tracer) 18; container body 19; casing (liner) 16 horizontal section of the well.

In FIG. 8 is a diagram of a studied horizontal section of a well with multi-interval (multi-zone) hydraulic fracturing, where: casing 21 is shown; packers 22; oil reservoir 23; the individual intervals of the horizontal barrel 24, hermetically limited by the packers 22; ports of interval fracturing 25; bottom-hole zones of 26 individual intervals of the horizontal trunk; hydraulic fractures 27.

In FIG. 9 is a graph of the arrival of the IIK indicator

In FIG. 10- schedule of receipt of the IIN indicator

In FIG. 11 is a graph of the receipt of the IIR indicator

In FIG. 12 is a graph of the receipt of the IFN indicator

In FIG. 13 is a graph of the arrival of the indicator IGF

In FIG. 14 - comparison of data on the performance of wells No. 1564, bush No. 344, Vyngapurovsky field

In FIG. 15 - data on the relative mass of the output indicators

In FIG. 16 - performance data of 1-5 multistage ports

In FIG. 17 - data on the coefficient of beneficial participation of 1-5 hydraulic fracturing ports

Key terms, concepts and abbreviations

Hydraulic fracturing (hydraulic fracturing), eng. Hydraulic fracturing, tracking, is one of the methods of intensifying the operation of oil and gas wells and increasing the injectivity of injection wells. The method consists in creating a highly conductive fracture in the target formation to ensure the flow of produced fluid (gas, water, condensate, oil or a mixture of them) to the bottom of the well, increasing production or injectivity, improving fluid connectivity between the well and the formation [http: //ru.wikipedia .org / wiki / hydraulic fracture].

The hydraulic fracturing method is the main tool for developing low-permeability reservoirs and low-yield wells. It was the development and large-scale implementation of hydraulic fracturing that made it possible to transfer low-permeable unproductive reservoirs into the category of recoverable oil reserves, the drilling and operation of which without hydraulic fracturing in Western Siberia is technologically impossible.

The essence of the hydraulic fracturing method is the formation of cracks in rock masses saturated with oil or gas produced. The effect of the method is based on increasing productivity, the so-called well flow rate during the formation of faults, extended cracks in oil and gas bearing formations, by forming a penetrating branched drainage system.

Hydraulic fracturing is carried out in the well by injecting at a high speed a significant amount of the working fluid supplied under a pressure of 100 MPa, creating high pressure at the bottom of the well. When the pressure of the working fluid exceeds the horizontal component of the rock pressure, a vertical crack is formed. And, accordingly, in the event that the pressure of the working fluid exceeds the vertical component of the rock pressure, the rock ruptures horizontally.

At the same time as the working fluid, as a rule, the fixing agent is injected - it can be sand or other solid material that will fill the crack and not allow it to close. In order to minimize leakage of the working fluid into the formation or into groundwater, thickeners are used. For the same purpose, the layers are isolated from each other, for example, due to the multi-column design of the well, as well as the use of particularly strong materials in the cementing process. The mixture that is pumped into the well during hydraulic fracturing consists of 99% water and sand (or a special agent, proppant), and 1% of chemical reagents [http://kniganefti.ru/word.asp?word=147 ].

Multistage hydraulic fracturing (MHF) is one of the newest and most advanced technologies in the oil industry, which is more effective for horizontal wells. The difference between this technology and simple hydraulic fracturing is that several hydraulic fractures are carried out in turn. [http://kniganefti.ru/word.asp?word=152].

Multi-zone (multi-interval, interval) hydraulic fracturing - consecutive hydraulic fracturing of a formation in one well at several bore intervals delimited by casing packers.

Hydraulic fracturing port - a device that provides access to the bottomhole zone of a well for hydraulic fracturing, through which subsequent production of well fluid or gas is usually carried out by means of producing and injection wells.

A manifold is an element of oil and gas fittings in the form of several pipelines, usually fixed on one base, designed for high pressure and connected according to a certain pattern, and equipped with the necessary shutoff, other fittings, SR drill sleeves and expansion joints [https://ru.wikipedia.org/ wiki / manifold].

Tubing pipes (tubing) - pipes for the extraction of liquid and gas from wells, injection of water, compressed air (gas) and the production of various types of work on the ongoing and overhaul of wells.

Proppant (or proppant, from the English propping agent - “proppant”) is a granular material that is used in the oil industry to increase the efficiency of well returns using hydraulic fracturing technology. Serves to preserve the permeability of cracks obtained during hydraulic fracturing. It is a granule with a typical diameter of 0.5 to 1.2 mm.

Indicator (tracer, tracer, tracer, chemical label, reagent indicator) - substances that have the property to dissolve or disperse in the borehole fluid and that can be reliably identified, and their amount is accurately measured in the borehole fluid stream in low concentrations.

Breaker - a chemical used in hydraulic fracturing technology to destroy hydraulic fracturing gel after injection of hydraulic fracturing gel with proppant.

Utility Model Implementation

The proposed method for studying sections and ports of a horizontal wellbore is based on recording data on the quantitative movement of indicators from the bottom-hole zones of the well intervals separated by packers into the wellbore together with the carrier fluid, taking into account the filtration-capacitive parameters of the productive deposits of the formation, changes in the reservoir parameters and bottomhole pressures.

The indicators used must not disturb the geochemical balance of the formation fluids, worsen the oil-displacing properties of the injected water and reagents, and affect the technological characteristics of the fracturing fluid and the properties of the proppant. Therefore, before entering specific indicators, a study is conducted on their compatibility with each other, with the fluids available in the well and the substances used in the development of the well.

The main condition for the study is the technical health of the wellhead equipment, tubing, tubing and leak tightness of the annulus.

It is advisable to mainly use microgranules as indicators, polycondensation resin (melamine formaldehyde or melamine urea formaldehyde) painted with a luminescent dye (fluorescein (green indicator), rhodamine B (red indicator) and others).

The selection of indicators for research is carried out from amongst well-studied and successfully used in oil production stable reagents for tracer studies of oil reservoirs, in particular: fluorescent reagents, salts of nitric, thiocyanate, phosphoric acid, urea and thiocarbamide.

The indicators used must not disturb the geochemical balance of the formation fluids, impair the oil-displacing properties of the injected water and reagents, and affect the technological characteristics of the fracturing fluid and the properties of the proppant.

The main requirements for indicators used in conducting tracer studies of oil reservoirs are as follows:

good solubility or dispersibility in the traceable fluid and insolubility in other fluids saturating the formation;

stability of physical and chemical properties in reservoir conditions in carrier fluids;

high accuracy and sensitivity of the method for determining indicators;

safety for research personnel;

availability for widespread use;

the ability to identify individual indicators in their mixtures.

their introduction into the composition of hydraulic fracturing fluids should not affect the technological parameters of the gel (crosslinking time, strength and - timely degradation at specific reservoir temperatures).

Before starting the study, it is advisable to check the influence of the additives of the indicators on the hydraulic fracturing fluids used, on the physicochemical and rheological properties of the gel and its destruction at a specific reservoir temperature. As a sample for comparing the characteristics, it is advisable to use the gels used with hydraulic fracturing without additives.

As a result of preliminary testing, tracers that are inert with respect to the components of the fracturing gel gel do not affect its physicochemical and rheological properties, as well as the destructive ability of the breaker reagent (a chemical reagent designed to break the fracturing gel after pumping the gel with proppant into the well )

The range of initial concentrations of the indicators was chosen from 0.05 g / dm ³ to 0.5 g / dm ³ , with their correct determination in the return flow of liquid when diluted 1000-10000 times.

The volume of the rim labeled with fluid indicators is determined based on the required design volume of the carrier fluid for the j-th fracturing stage (well interval):

V _j = Vggr _j ,

where Vggr _j is the design volume of the carrier fluid for the jth fracturing stage, m3.

The amount of the initial mass of the indicator for the j-th stage of hydraulic fracturing is determined as follows:

M _{0, j} = V _j · C _{0, j} ,

where V _j is the volume of the rim of the labeled fluid for the j-th stage of hydraulic fracturing, m3;

C _{0, j} is the initial concentration of the indicator for the j-th fracturing stage, kg / m3.

The transfer of indicators from the bottomhole zone of the well to the wellbore through the port occurs due to the movement of the fluids contained in the formation (oil, water, gas). The number of indicators carried by fluid flows into the wellbore is proportional to the number of fluids.

Thus, by analyzing the variety and number of specific indicators carried by the flow of the borehole fluid to the surface, it is possible to determine with sufficient accuracy the amount of a particular carrier fluid and the specific interval from which this fluid arrived.

Interval placement of indicators in the bottom-hole zones of a horizontal well can be performed in various ways (options):

Option 1 - indicator fluids (dispersions based on microgranules of indicators) are pumped into the bottomhole zone through the open hydraulic fracturing port before hydraulic fracturing.

A typical work schedule for conducting multi-zone hydraulic fracturing includes operations to open one of the ports, and preliminary “test” injection of hydraulic fracturing fluid into the port.

Tracers according to option 1 can be introduced into a container with water intended for the preparation of hydraulic fracturing fluid.

The flow chart and the place of entry of tracers during hydraulic fracturing according to option 1 is shown in FIG. 3.

Option 2 - indicator fluids are injected into the bottomhole zone together with hydraulic fracturing fluid (hydraulic fracturing gel).

In this embodiment, it is advisable to apply the indicator substances directly to the “blender” (a device for preparing hydraulic fracturing fluid).

The flow chart and the place of input of indicators during hydraulic fracturing according to option 2 is shown in FIG. four.

Option 3 - indicator substances are mixed with proppant (proppant), or applied to the surface of the particles of proppant and they fall with it into hydraulic fractures, which are also parts of the bottom-hole zones of the well.

In this case, a water or oil-soluble composition containing indicator substances is applied to the surface of the proppant (Fig. 5).

The proppant for each stage of hydraulic fracturing and for each interval of the well is labeled with an individual color for the stage or type of indicator. In the process of hydraulic fracturing, the proppant is pumped into hydraulic fractures and becomes part of the bottom-hole zone of the corresponding interval of the well, and thus the indicators fall into the bottom-hole zones of the corresponding intervals of the well.

Option 4 - on the basis of indicator substances, solid substances are prepared having properties that will dissolve in water and / or oil and placed in the proposed devices (containers with an indicator), which are located in the annulus of the well at the stage of its construction by attaching horizontal sections of the well on the outer wall of the casing .

The container with the indicator is a device that encircles the “liner” pipe (casing of the horizontal section of the well), consisting of an external protective casing, a chamber with an indicator, and fittings (calibrated holes) for fluid inlet and outlet (Fig. 6).

The flow of formation fluid is washed by containers with indicators and, through appropriate fittings or valves, enter the internal chambers of the containers in which the indicators (tracer trains) are located.

Indicators of reservoir fluid are removed from the containers and through the corresponding ports enter the wellbore.

Option 5 — the indicators are placed in glass ampoules that are destroyed at certain points, for example, under hydraulic fracturing pressure, which are placed in containers located in the annular space of the well at the stage of its construction (Fig. 7). During hydraulic fracturing operations, the ampoules with the indicator under the influence of hydraulic fluid pressure fracture and the indicators of the substance fall into the bottom-hole zones of the corresponding intervals.

Unlike option 4, the placement of indicators in glass ampoules allows the casing to be launched without loss of indicator substances. The wall thickness and strength of the ampoules with the indicator is selected so that their destruction occurs at certain hydraulic fracture pressures. Thus, the problem of supplying various indicators to the bottomhole zones of the well after the start of hydraulic fracturing operations at the appropriate intervals is solved, which increases the accuracy of the placement of indicators and increases the ability to track the output of indicators for a longer time.

There are other options for the delivery of indicators in the bottom-hole zones of specific intervals of the horizontal wellbore, providing selective hit of specific indicators in the bottom-hole zones of the corresponding intervals of the well.

The analysis of the quantities carried out by the well fluid indicators can be performed by one of the known methods for the analysis of indicators.

The most suitable is a method for determining the quantitative composition of luminescent and fluorescent indicators using the microscopic method.

To implement this method, a sample of the wellbore fluid (fluid from the well) containing a mixture of various indicators coming from different intervals of the well is taken.

The selected sample is thoroughly shaken and filtered through a membrane filter with a pore diameter of 0.45 μm. For this purpose, a clean funnel for filtering the sample with a neatly inserted membrane filter is installed on a Bunsen flask, in which the necessary vacuum is created using a vacuum pump. The filtering process is continued until it becomes difficult due to clogging of the filter.

After completion of filtration, the filter funnel is carefully unscrewed so as not to contaminate the filter, and the filter is transferred to a glass slide.

On a glass slide, the filter on top is closed with a coverslip, pressed tightly against the glass slide, and in this state the glasses are fixed at the ends with adhesive tape.

The filtrate volume of the filtered sample is measured with a graduated cylinder, and then the sample is disposed of. After each filtering procedure, the funnel is dried and washed with technical acetone for 3 minutes to remove the indicator of the previous sample.

A filter with tracer particles deposited on it is viewed in a luminescent microscope (for example, Lumam-I1, MLD-1) upon excitation of fluorescence with blue-violet rays (a beam-splitting plate 360-440 nm + an FS-1-4 light filter). As a blocking filter, a ZhS18 or ZhS19 filter is usually used.

Microscopy is carried out using a lens × 10 × 0.4 L and a binocular system 1.1 × 7. If necessary, use a × 40 lens or other eyepieces.

In the field of view of a luminescent microscope, indicator particles are easily identified by the brightness and color of fluorescence, as well as by their size and shape even in the presence of foreign particles.

If the number of indicator particles on the filter is small (less than 5 particles in the field of view), then the entire surface of the membrane filter is scanned and all deposited indicator particles are taken into account.

If the number of indicator particles in the field of view is more than 5, then particles in several random fields of view are considered.

To count indicator particles, at least 20 fields of view are randomly selected. It is better not to do this arbitrarily, but to move to a new field of view by turning the micrometer screw of the microscope stage by a certain amount. Based on the calculation of the fields of view, the arithmetic average number of particles in the field of view is calculated.

The number of particles of the indicator N in 1 cm ^{3 is} calculated by the formula

, где

where

n is the average number of particles in one field of view;

S is the surface area of the filter, cm ² ;

a is the area of the field of view, cm ² ;

V is the volume of filtered water, cm ³ .

Examples of fields of view of the studied filter samples are shown in FIG. 1 and FIG. 2.

The result of the analysis is the identification of a certain ratio of the number of indicators of different colors.

Knowing what color of the indicator in which interval was placed, we can reliably estimate the contribution of each interval to the total production rate of the well.

The volume of fluid received from each interval is calculated by the formula:

Q _int1 = Q _SLE ∗ (K _int1 / (K _int1 + K _int2 + ... K _intX ), where

Q _int1 - the amount of fluid received from interval 1

Q _SLE - the total amount of fluid received from the well

K _int1 - the number of color indicator corresponding to the interval 1

K _int2 - the number of color indicator corresponding to the interval 2

K _intX - the number of color indicator corresponding to the interval X

The water cut of the products of each interval is calculated as the ratio of the amount of oil-soluble indicator to the sum of oil-soluble and water-soluble color indicators corresponding to the interval:

W _int1 = K _ITN1V / (K _int1N + K _ITN1V ), where

W _int1 - water cut interval,%

K _ITN1V - the amount of water-soluble color indicator corresponding to the interval 1

K _{int1n the} amount of oil-soluble color indicator corresponding to the interval 1

Research on the proposed method allows to obtain information about:

distribution of the indicator output concentration for each interval;

the mass of the indicator extracted on the daily surface for each interval;

shares of inflow and productivity for each interval.

To confirm the feasibility of industrial implementation and achieve a technical result, pilot industrial work was carried out to download indicators during hydraulic fracturing at well No. 1564, bush No. 344, Vyngapurovsky field, Yamalo-Nenets Autonomous Okrug.

When conducting and interpreting the results obtained during the injection of indicators with multi-zone (multi-interval, interval) hydraulic fracturing, the following were taken into account:

data on the composition of the gel for hydraulic fracturing fluid with the provision of samples of reagents, water and proppant in the laboratory for testing indicators and analyzing samples;

design parameters of hydraulic fractures;

well development history data for the sampling period.

The required volumes of indicator concentrates were prepared separately for each stage of multistage hydraulic fracturing.

The indicators were supplied to the flow for the entire volume of the main hydraulic fracturing (buffer stage + proppant supply stage), excluding the sell-activation stage of the next port.

The indicators were supplied by means of a pump with a flow rate of 2 l of concentrate per 1 m ^{3 of} gel with recording of the supply by analogy with any liquid reagent supplied to the stream during hydraulic fracturing.

According to the results of tracer studies by the proposed method, the following overall effectiveness of stimulation of the target hydraulic fracturing stimulation for well No. 1564, bush No. 344, and Vyngapurovsky field was revealed:

Prior to the start of the tracer studies, reservoir water samples were taken for the content of indicators proposed for injection from the immediate surroundings of well No. 1564/344, designed for multi-stage hydraulic fracturing with injection of indicators: from wells No. 1553/344; No. 1561/344; No. 5130/351; No. 6427/351; No. 1563/344 and No. 1559/344.

Sodium thiocyanate (Cipher IIR), sodium nitrate (Cipher IIN), sodium phosphoric acid (Cipher IIF), carbamide (urea) (Cipher IIK), sodium fluorescein (Cipher IFN), and rhodamine C (Cipher IFR) were used as indicators.

When physicochemical analysis of samples for the content of indicators was carried out:

analysis of background samples and the construction of calibration dependencies;

sample preparation - separation into oil-water phases, removal of mechanical and colloidal impurities from water;

conducting analysis of samples - determining the concentration of tracers in the sample;

if necessary, repeat the stage of preparation and analysis of the sample.

The contents of the indicators were determined by spectrophotometric methods. The results are presented in table 1.

The results of the analysis of liquid samples of the return flow of the borehole fluid from the producing well No. 1564/344 are presented in table 2 and in FIG. 8-12.

The mathematical interpretation of the obtained laboratory data of the analysis of the samples was carried out in order to evaluate and confirm the effectiveness of the stages of hydraulic fracturing and determine:

- the amount of indicator extracted on the surface for each stage (each interval, port);

- shares of inflow and productivity for each stage of hydraulic fracturing;

- the overall effectiveness of stimulation of the targeted effects of hydraulic fracturing.

When conducting mathematical processing of the results of the analysis of the samples, we used the data on the measurements of the liquid flow rate and the water cut data for each sample taken, which are presented in Table 3.

In FIG. 13 shows for comparison the data of daily average performance of the well and the data on the measurements of fluid flow rate and water cut for each sample taken.

The required time for taking the entire volume of hydraulic fracturing fluid, which contains the downloaded indicators (total hydraulic fluid volume in all intervals of 491.7 m3), based on data on the flow rate of water in the entire well for the sampling period, is on average 6.86 days (excluding fluid leaving beyond the formed fractures).

The duration of fluid sampling for subsequent laboratory tests for the content of uploaded indicators in them was 10.5 days.

According to the results of the mathematical interpretation of the indicator output data during the sampling period, the following were selected:

IFN indicator, injected as part of hydraulic fracturing fluid for port No. 1 - 1094 g, which is 30.4% of the initial injected mass of the indicator;

IIR indicator, injected as part of hydraulic fracturing fluid for port No. 2 - 19852 g, which is 56.7% of the initial injected mass of the indicator;

IIN indicator, injected as part of hydraulic fracturing fluid for port No. 3 - 3827 g, which is 19.9% of the initial injected mass of the indicator;

IIC indicator, injected as part of the hydraulic fracturing fluid for port No. 4 - 28335 g, which is 81.0% of the initial pumped mass of the indicator;

the IGF indicator injected as part of the hydraulic fracturing fluid for port No. 5 is 395 g, which is 11.3% of the initial pumped mass of the indicator.

The share of water inflow and productivity for 1-5 hydraulic fracturing ports:

for port No. 1, the share of inflow from the total inflow through the well is 16%, the productivity of the port is 20 m3 / day, the volume of channels replaced by labeled liquid is 205 m3;

for port No. 1, the share of inflow from the total inflow through the well is 30%, the productivity of the port is 37 m3 / day, the volume of channels replaced by labeled liquid is 384 m3;

for port No. 3, the share of inflow from the total inflow at all ports is 6%, port productivity is 7 m3 / day, the volume of channels replaced by labeled liquid is 74 m3;

for port No. 4, the share of inflow from the total inflow at all ports is 43%, port productivity is 52 m3 / day, the volume of channels replaced by labeled liquid is 547 m3;

for port No. 5, the share of the inflow from the total inflow at all ports is 6%, the port capacity is 7 m3 / day, the volume of channels replaced by labeled liquid is 76 m3.

The results of the mathematical interpretation of the indicator output data for 1-5 hydraulic fracturing ports are shown in Table 4 and in FIG. 14-17.

Tracer studies conducted, which consisted in the injection of various indicators together with proppant injection for each of the 1-5 stages of hydraulic fracturing (1-5 intervals), the subsequent selection and analysis of return flow samples after completion of hydraulic fracturing and the call of inflow from the well to assess the success of hydraulic fracturing operations for well No. 1564, bush No. 344, of the Vyngapurovskoye field, the following information was obtained:

distribution of the indicator output concentration for each stage of hydraulic fracturing (each interval, each port);

the mass of the indicator extracted to the day surface for each stage of hydraulic fracturing (each interval, each port);

fractions of inflow and productivity for each stage of hydraulic fracturing (each interval, each port).

Analysis of these parameters allowed us to evaluate the success of hydraulic fracturing operations in the well.

The share of inflow and productivity for each stage of hydraulic fracturing (each interval, each port) was estimated under the accepted conditions that the current flow rate of water in the well was the sum of the inflows of water from 1-5 hydraulic fracturing ports.

As a result of these tracer studies, the following stimulation efficiency of the hydraulic fracturing target effect was established for well No. 1564, well No. 344, Vyngapurovsky research field:

For two of the five studied hydraulic fracturing ports (ports 2 and 4), the greatest efficiency from hydraulic fracturing takes place. For these ports, there is more than 50% of the indicator output from the initial pumped mass of indicators, the share of inflow from these stages is 30 and 43%, respectively, of the total water inflow through the well.

For ports 1, 3 and 5, the efficiency of hydraulic fracturing is low. For these ports, there is no more than 30% of the indicator output from the initial injected mass, the share of inflow from these stages is 6-16%, respectively, of the total water inflow through the well.

For two of the five studied hydraulic fracturing ports (ports 2 and 4), the greatest efficiency from hydraulic fracturing was revealed. For these ports, there is more than 50% of the tracer output from their initial injected mass, the share of inflow at these intervals is 30 and 43%, respectively, of the total water inflow through the well.

Low efficiency was revealed for hydraulic fracturing ports 1, 3, and 5 from hydraulic fracturing. For these ports, there is no more than 30% of the tracer output from their initial injected mass, the share of inflow from these stages is 6-16%, respectively, of the total water inflow through the well.

The scope of the proposed technology is not limited to the method of operation and equipment of horizontal multi-interal wells developed by hydraulic fracturing, fluid inflows and injectivity levels, viscosity and gas fluid factor.

The proposed method does not impose any restrictions on the modes of operation of the wells and allow tracer studies directly during the operational functioning of the producing well.

Thus, all the essential features of the utility model are in a causal relationship with the technical result obtained from the use of the utility model.

The specific design features of the proposed devices and the operation of the method are determined experimentally and practically verified during the detailed field tests, which is confirmed by the attached photographs and drawings.

Field tests of the fire extinguishing device and method showed a confident solution to the problem and achieving the required technical result, namely, the implementation of the utility model provides:

increasing the reliability of the quantitative determination of fluid flow (flow measurement) in each individual interval of the well with a horizontal end (horizontal well);

increasing the reliability of determining the ratio of phases (water / hydrocarbon) coming from the reservoir from each individual interval of a horizontal well;

improving the accuracy of measuring the flow rate and composition of the borehole fluid in various intervals of the horizontal well;

increasing the reliability of research results by choosing the properties of indicators, allowing to obtain an adequate model that reflects the natural dynamics of liquid-phase flows in various intervals of horizontal wells;

increasing the efficiency of hydrocarbon field development by making informed decisions based on more complete and reliable information about the studied development object, as well as by optimizing the reservoir pressure field for each of the horizontal well intervals, which ultimately leads to an increase in the hydrocarbon recovery coefficient for the field;

- expanding the range of application of hydraulic fracturing technology by providing the introduction of indicators (tracers) with desired properties with any liquid carrier, including those used with proppant fluids.

As separate elements and nodes of the device options and the method implementation, various well-known and traditional structural solutions, materials and technologies commonly used in the development and operation of horizontal oil production wells with separated packers at intervals and interval hydraulic fractures can be used in the mining oil industry and geophysical research layer.

Presented a detailed disclosure of the proposed utility model and detailed examples of industrial implementation prove a confident solution to the problem, achieve the required technical results, the completeness of the disclosure of the utility model and the possibility of its implementation in an industrial way.

Claims (11)

1. Device for tracer research of a horizontal well with packers separated by intervals of interval hydraulic fracturing, comprising a container with an indicator, characterized in that it is arranged to be placed on the outer wall of the casing of the well in the bottomhole zone of the well interval and introduce the indicator into the wellbore zone wells and made in the form of a container containing a housing with means for attaching it to the outer wall of the casing of the well, an external protective a casing and at least one chamber with an indicator in a pressure-breakable ampoule and openings and channels for entering the chamber with an indicator of formation fluid and exiting formation fluid with an indicator into the bottom-hole zone of the well interval. 2. The device according to claim 1, characterized in that it contains an indicator in an ampoule that is destroyed by hydraulic fracturing pressure. 3. The device according to claim 1, characterized in that the openings and channels for entering the chamber with the formation fluid indicator and exiting the formation fluid with the indicator are calibrated. 4. The device according to claim 1, characterized in that the openings and channels for entering the chamber with the formation fluid indicator and out of the formation fluid with the indicator comprise means for controlling the amount of formation fluid entering the chamber with the indicator and / or the amount of formation fluid leaving it liquids with an indicator, made, for example, in the form of fittings or valves for regulating the amount of formation fluid entering the chamber with an indicator and / or the amount of outgoing formation fluid with an indicator. 5. The device according to p. 1, characterized in that the container is arranged to be placed on the outer wall of the well casing in the bottom-hole zone of the well interval in the immediate vicinity of the interval port. 6. The device according to p. 1, characterized in that it is configured to introduce an indicator into the bottomhole zone and to determine by the number of the indicator in the fluid from the well the effectiveness of hydraulic fracturing in a given interval of the well and the functioning parameters of this interval of the well. 7. The device according to claim 1, characterized in that it is configured to introduce an indicator into the bottomhole zone of the well interval and to determine by the amount of the indicator in the fluid from the well the amount of fluid produced from the given well interval. 8. The device according to p. 1, characterized in that it is made with the possibility of introducing the indicator into the bottomhole zone of the well interval and the ability to determine the number of indicators in the liquid from the well of the flooding of the fluid produced from this interval of the well. 9. The device according to p. 1, characterized in that it is made with the possibility of placement on the outer wall of the casing of the well before hydraulic fracturing. 10. The device according to p. 1, characterized in that the indicator contains luminescent and / or fluorescent indicators, for example microcondensation polycondensation resin, for example melamine-formaldehyde resin or melamine-urea-formaldehyde resin, painted with a luminescent substance: green fluorescein or red rhodamine B fluorescent, or substances of other colors soluble in formaldehyde resins. 11. The device according to claim 1, characterized in that the indicator comprises oil-soluble or oil-dispersible and water-soluble or water-dispersible indicators with the ability to determine the ratio of water to oil in a liquid from a well interval.

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