RU2544360C1 - Device for measurement of composition and flow rate of multi-component liquids by method of nuclear magnetic resonance - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: device for measurement of composition and flow rate of multi-component liquids using a method of nuclear magnetic resonance (NMR) includes a NMR relaxometer with a sensor having a tube for irradiation of a liquid flow and receiving NMR spin-echo signals, as per which liquid parameters are determined, a sampling system containing a measurement pipe connected via the sampling tube to NM relaxometer. The measurement pipe has a conical expander, and in the sampling tube there installed is a branch pipe having a possibility of being moved along the cross-section of the conical expander; with that, the conical expander is located vertically, in the measurement pipe, before the liquid flow enters the conical expander, there installed is a protective net; in the conical expander there installed are pressure strain gauges, and in the cavity of the lower part of the conical expander there arranged along the perimeter are geared rings; on the sampling tube there arranged are electromagnetic coils for control of movement of the branch pipe; with that, control of movement of the branch pipe of the conical expander is performed by the introduced controller connected to electromagnetic coils.

EFFECT: eliminating phase disengagement in a conical expander of a measurement pipe and a possibility of blockage of a sampling branch pipe with asphaltene-resin inclusions and mechanical impurities; providing effective turbulisation and homogenisation of a liquid flow in the conical expander of the measurement pipe; automation of a measurement process.

2 cl, 1 tbl, 2 dwg

Description

The invention relates to resonant radio spectroscopy, in particular to measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance (NMR), and can be used in the analysis of any proton-containing liquid mixtures in various industries, mainly for measuring the composition and flow rate of fuels, oils, oil and chemical products, food liquids in oil production, oil refining, as well as in energy facilities in the analysis of liquid fuel. Mostly the device can be used in the selection and analysis of samples of oil-water-gas mixture from the pipeline at the well and / or group metering unit (GZU), as well as on the main pipe.

State of the art

In the 80s there was a tendency towards a transition to flowmeters without moving parts and without stopping the flow. The interest in measuring multiphase production of wells (borehole fluid - SKZh) without preliminary separation is associated with the development of small and offshore fields, the use of more technological schemes with a minimum of equipment, with platforms on which the presence of operating personnel is not provided. The measurement of the flow rates of all well fluids without dividing them into phases, without using moving parts and without controlling the process is advisable, since it eliminates the cost of separators. But the complexity of the problems involved is enormous.

When developing oil fields, measurements of oil, gas and water flow rates are performed at least twice. They measure what is mined (operational accounting) and what is sold / transferred (commercial accounting).

Production measurements are made at the wellhead, and oil or gas sold is produced at or near the product pipeline, and usually after separation into components. According to GOST 8.615-2005, it is now required to measure the extracted SKZh to calculate the tax amount. Measurements are also needed to monitor the size of reserves, control the operation of plants, record keeping, optimize the production process and plan field development, i.e. technical (team) accounting is also needed. At the same time, according to GOST 8.615-2005 at the well, measurement errors should be no more than: fluid mass ± 2.5%; net oil mass ± 6% with water cut to 70%; ± 15% at water cut to 95%; the volume of oil gas ± 5%. When changing ownership of oil, they usually require that measurements of oil or gas production rates be carried out with an accuracy of 0.35-0.5%. As for the quality of oil (concentration of water, salts, density, viscosity), the main data comes from laboratories with a frequency of 2, 6 hours, 2 times a day. Laboratory data are the most reliable, but the large discreteness of the analysis and subjective factors do not allow timely responses to changes in oil quality. This is especially pronounced when passing through the metering unit of small batches of oil with different properties from different producing companies.

Therefore, the problem arises of monitoring the entire SKZh and using automation to combine the high accuracy of laboratory analysis with the constancy of the work of flow analyzers. The requirement for flexibility was determined by the development of operational, in-line and laboratory control. The practice of Western oil companies shows that none of these areas is dominant and their combination is optimal.

The control at the well is overwhelmingly carried out on group measuring units (GZU) of the Sputnik type by phase separation and measuring the flow rate and quality of the phases by interrogating pipelines from the wellbore. Measurement accuracy does not exceed 4%.

The main objective of the reconstruction of oil metering stations is to equip them with an automated system for measuring the quantity and quality of oil (ASIKN). But their cost reaches $ 300 thousand to $ 0.7-1.2 million. For small oil and gas companies that supply more than 30% of oil production, their price is too high.

The solution to the problem of measuring production at the wellhead is seen from the experience of Western companies in replacing a complex separation system with a multiphase device for measuring the entire flow, requiring minimal or complete lack of maintenance.

In 1989, prof. Roger Baker, in his Multiphase flow move son article, proposed a multiphase flow meter with a preliminary mixer-homogenizer, a sampler for partial separation of water and gas, with a gamma source on two isotopes for determining the density of the SCR and a volumetric flow meter. But static homogenizers have a limited speed range of 0.75 m / s to 4 m / s at which they operate. In addition, according to modern requirements of oil companies, the pressure drop across the analyzer (due to flow resistance) should not exceed ΔР = 0.25-0.5 MPa. Multiphase flow meters (MFR) open up possibilities for measuring oil, water and gas production rates in real time, allow a new approach to field development and optimization of the production process, since it is possible to better control the well and the field and increase the balance reserves and oil production. The data obtained allows us to make operational decisions, for example, at the choice of the moment of closing a well with a high water content.

Obstacles to the use of MFR: overcoming conservatism in the transition to new technologies; price / perception of a new price; a large number of existing gas separation plants. Field of application of MFR: multiphase oil-water-gas media with negligible sand concentration; gas with trace concentrations of water and sand; water-cut of water-oil emulsions with microconcentration of sand; clay solutions - a suspension of solid particles in a liquid with a trace gas concentration. That is, there should be only traces of sand, water, gas.

Schlumberger VFR technology with a combination of a venturi to create a differential pressure and a gamma source fractionometer with a gamma-ray spectrum at two energy values provides an acceptable accuracy of 5% for long sampling periods. Calculation of flow is carried out according to a physical model that takes into account the features of a multiphase flow. The price of the equipment is $ 200,000.

The operating principle of Weatherford meters is near-infrared absorption spectroscopy, in which the optical density D is measured at several wavelengths. An Alpha VS / R flow meter is used to monitor gas flows, but without a radioactive source.

Agar is promoting the MPFM-50 multi-flowmeter based on the principle of a Coriolis flowmeter with a high-precision moisture meter. When choosing these flowmeters, companies are guided by the principle of minimum pressure drop and the absence of radioactive sources.

Of the MFR, it should be noted “Ultraflow” developed by the Industrial Company LLC (Moscow) using ultrasound sensing methods. Measurement of water cut, speed and gas content is carried out in two channels of different diameters. Comparative characteristics of the MFR are shown in table 1.

Table 1
Comparative technical characteristics of MFR Name of MFR (company) Flow rate, t / day, m ³ / day Pressure, MPa, and T Weight kg Error,% Dimensions OZNA Vx - Schlumberge 2009 150-6000 4 MPa 210 / ± 2.5% (crude oil consumption) 684 × 479 × 467 / 270 / 663 × 686 × 633 / 398 ± 5% (volume and vol. Gas consumption 742 × 766 × 930 mm MPFM-50 (Agar Corporation, Inc. USA) 2009, frequency 4 MHz Protection IP65 / IP66 State Register No. 43523-09 Liquids 1-160 m ³ / hour Up to 69 MPa Temperature 0-232 ° C 200 ± 2% (water and oil) 76 × 51 × 127 cm ⌀50 / 0.9 × 0.9 × 2.4 m Gas 14-24000 m ³ / h ± 5% (gas) ⌀80 / 1.2 × 1.4 × 3 m For the environment: ⌀100 / 1.4 × 1.5 × 3.7 m Vyazk. 0.1-200 cP Dense 700-1100 REMMS with separation (Weatherford),), 2008. 40-2400 140 bar at 150 ° C max 2700-4500 ± 2% (water and oil) 274 × 213 × 213 cm ± 5% gas Alpha-Vs / R / D (Weatherford), 2009. On IR analysis 40-13000 Up to 420 bar (at 150 ° C) 200-1500 ± 2% (water and oil) 160 × 50 × 50 cm ± 5% (gas) Ultraflow (Industrial Company, APZ) 2001 20-400 Up to 10 MPa 80 ± 2.5% (crude oil consumption) 140 × 47 × 46 cm 50-1000 one hundred 140 × 51 × 51 cm 100-2000 120 ± 5% (gas consumption 140 × 59 × 59 cm Sputnik-M with separation and ASIKN. Price - 1.575 million p. (≈2006 g.) (SIBNA, Tyumen) 1-400 (liquids) ± 2.5% (oil consumption) Block box 4.0 1500 240 × 240 × 400 cm 40-20000 (gas) ± 5% (gas consumption)

When analyzing foreign and domestic non-separation MPFs, the following drawbacks are noteworthy: the lower limit of flow rate measurements, which begins with 24 t / day in liquid, is rather high. In domestic wells, it is much lower and reaches - 0.5 tons / day: consumers are scared away by the source of gamma radiation in the device; a long sampling time period is required; the liquid should contain a negligible concentration of sand, and the gas should contain trace concentrations of water and sand; heavy weight and dimensions. Meanwhile, according to the requirements of domestic oil companies (including OAO Tatneft), the flowmeter parameters should be: flow rate range 0-600 t / day; the measurement error of the mixture flow rate is 1.5-4.0%, the pressure is up to 6.4 MPa, the gas content is V _G / V _Ж = 0-25, the ambient temperature is -60 ÷ + 50 ° C, the limits of the permissible measurement errors: mixture ± 1 , 5 ÷ 4%; water ± 2.5 ÷ 6%; oil ± 2.5 ÷ 6%; gas ± 5 ÷ 10%; the permissible pressure difference across the analyzer is 0.25-0.5 MPa, viscosity ≤600 cSt, explosion protection, the number of workers serving the installation - 1, category 4.

As you know, sampling contributes half the measurement error and will be completely representative if 100% of the sample is analyzed. This is almost impossible to achieve.

Therefore, according to the recommendations of Jiskoot Autocontrol, Ltd, in order to increase the representativeness of partial sampling, it is necessary to fulfill the following requirements: create maximum uniformity of components in the pipeline with a uniform distribution of components over the cross section, i.e. it must either be ensured or it must be possible to select pipe sections at different levels; carry out sampling from the pumped liquid, i.e. from a vertical flow to prevent gravitational separation of components; to prevent sampling of a distorted sample, the sample taken must be proportional to the speed of the flow, i.e. the isokinetic condition must be met in accordance with change No. 1 in GOST 2517; a sample should be taken often enough to record a change in parameters (W, density, etc.); to carry out laboratory analysis with the correct processing and mixing of samples - this is the last instance that determines the value of sampling. The representativeness of the sampling is influenced by the position of the pipe. When the sampler pipe is horizontal, streams will stratify (especially at low speeds) and the pipe will not be completely filled.

When controlling multiphase flows and SLE, analyzers based on the method of nuclear magnetic resonance (NMR) have several advantages: zero lower limit for measuring flow (can be measured in a stopped flow); independence of flow measurements from the concentration of sand and other inclusions; lack of radioactive radiation sources; the possibility of density measurements (if appropriate techniques are available), short analysis time (several minutes), full automation and small dimensions.

NMR flow meters can be single coil and double coil design. In single-coil NMR flow meters, the principle of the dependence of the signal amplitude, resonant frequency and phase on the speed of the medium is used. Their advantage is the simplicity of design, reliability, lack of dependence on the viscosity and density of the medium. They are most suitable for measuring multiphase liquids. In the speed range of 2-7 m / s, the accuracy of a single measurement is 2-2.5%. Two-coil designs of NMR flow meters, various versions of which were developed in the USSR, suggest two magnets - polarizing and analyzing.

Abroad, a single-phase NMR flowmeter was developed by BodgerMeter Manufacturing Co. for pipe diameters of 10, 20, 25, 50 and 150 mm with a measurement accuracy of 0.5% rel. from the limit of the scale, with the dimensions of the transducer 73 × 12 cm, the measuring unit 45 × 60 cm, pressure up to 8 MPa, the temperature of the medium being measured up to 400 ° C, the environment - 50- + 1200 ° C.

A similar NMR flowmeter MRG-P was developed in Japan with an accuracy of 0.5% rel., Flow measurement range 160-1200 l / h (3.8-29 t / day), for diameters of 9 (25.50) mm, temperature of the medium to 120 ° C, environment 0-60 ° C.

In the USSR, in the 70s, an NMR flowmeter RMR OK No. 6823-78 was developed with the following parameters: accuracy of flow measurement 0.5% rel., Range 1.44-14.4 t / day, temperature of the medium measured 40 ± 10 ° C, environment 10-40 ° C, pipe diameter - 8 mm, dimensions of the measuring unit 53 × 40 × 20 cm.

The prototype of the invention is a device for measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance, including an NMR relaxometer with a sensor for irradiating the liquid flow and receiving spin-echo NMR signals, which determine the parameters of the liquid, a sampling system containing a measuring pipe connected a sampling tube with an NMR relaxometer, while the measuring tube has a conical expander, and a nozzle is installed in the sampling tube, having the ability to move over the cross section of the conical expander (RU patent for utility model No. 74710, IPC G01N 24/08, 07/10/2008).

The fluid flow entering the conical tube expander reduces the speed ν and increases the pressure P due to the continuity of the flow Q _i = S _i ν _i = const.

As a result, turbulence and homogenization of the SCR occurs, which through the inlet pipe enters with a velocity ν _i , determined by the position of the pipe in the section of the expander S _i , into the magnet sensor of the NMR analyzer and exits through the outlet pipe. As a result, the flow rate is determined by the pressure difference (P _T -P _i ) in the sections S _T and S _i , where S _T is the cross section in the pipe, S _i is the cross section in the conical expander corresponding to the position of the nozzle. When the pipe is located on the section of the measuring pipe, the pressure difference will be close to zero regardless of P _T in the pipe and the flow rate ν _D through the NMR sensor will also be close to zero, which is necessary for measuring the NMR parameters (relaxation times and concentration of water, oil and gas , dispersion, density, etc.) in a “stopped" flow. Structurally, this means the rejection of sample delivery pumps and valves requiring explosion protection and having a low service life.

The disadvantages of the prototype are the possibility of phase separation in a horizontally arranged conical expander of the measuring pipe, the possibility of clogging of the pipe with asphalt-resin aggregates and mechanical impurities, insufficient turbulence of the fluid flow in the conical expander of the measuring pipe, insufficient automation of the measurement process.

The objective of the invention is the elimination of phase separation in the conical expander of the measuring tube and the possibility of clogging of the sampling pipe with asphalt-resin inclusions and mechanical impurities, ensuring efficient turbulization and homogenization of the fluid flow in the conical expander of the measuring pipe, as well as automation of the measurement process.

The technical result is achieved in that in a device for measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance (NMR), including an NMR relaxometer with a sensor having a tube, for irradiating the fluid flow and receiving spin-echo NMR signals, which determine the parameters liquid, a sampling system containing a measuring tube having a conical expander connected by a sampling tube to an NMR relaxometer, and a pipe having the ability to move over the cross section of the conical expander, according to the invention, the conical expander is located vertically, the measuring tube has a settling cavity, and a protective mesh is installed in the measuring tube, before the liquid flow enters the conical expander, strain gauge pressure sensors are installed in the conical expander, and in the cavity of the lower part conical extender along the perimeter placed gear rings, on the sampling tube there are electromagnetic coils for controlling the movement of the pipe, and that control of movement of the nozzle section of the conical expander carried introduced controller coupled to the electromagnetic coils.

To measure the flow rate Q _{T, the} nozzle is located in a section that provides a flow rate for which the maximum slope of the dependence of the effective relaxation rate (T _2Eff ) ^-1 on the flow rate of the liquid is obtained, while the flow rate ν _T and flow rate Q _T in the measuring tube are determined respectively by the formulas ν _T = K _C S [(T _2Eff ) ^-1 ] / KS _D and Q _T = K _C S (T _2Eff ) ^-1 , where S _D is the cross-sectional area of the tube of the sensor of the NMR relaxometer, S is the cross-sectional area of the conical expander on nozzle position level, K = S _T / S _M - gear ratio, K _C - coefficient depending Q = K _{A D C} S (T _2Eff) ^-1 _(2Eff T) ^-1 = (T _2o) ^-1 + (τ) ^-1, T _2a - relaxation time in stationary fluid, τ - moment sensor being in fluid NMR and costs Q _i fluid component is determined by the formula Q _i = Q · P _i, where P _i - concentration of the i-th component of the mixture, determined from the decomposition components of the envelope of the spin-echo NMR signal of extrapolated to zero time values holdup of gas V _{G is} determined by the formula V _G = (A ₀ -A _G ) / A ₀ , where A ₀ , A _G are, respectively, the initial amplitudes when the NMR sensor is completely filled with crude oil and partially filled gas.

The invention is illustrated by drawings, where figure 1 shows the proposed device (side view), and figure 2 view a in figure 1 (top view).

In the drawing, the numbers indicate:

1 - measuring tube,

2 - cavity sludge,

3 - protective net,

4 - conical expander,

5 - flange

6 - sampling tube,

7 - pipe

8 - electromagnetic coils,

9 - temperature sensor,

10 - flange

11 - NMR relaxometer,

12 - pole tip

13 - tube of the NMR sensor,

14 - inductor,

15 - flange

16 - connector

17 - strain gauge pressure sensors,

18 - gear rings,

19 - main pipe

20 - case,

21 - pipe discharge sludge,

22 - cable

23 - transceiver

24 - controller

25 - control point (UP) of the dispatcher.

A device for measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance (NMR) includes an NMR relaxometer 11 with a sensor having a tube 13 for irradiating the liquid flow and receiving NMR spin-echo signals, which determine the parameters of the liquid, a sampling system containing a measuring tube 1 having a conical expander 4 connected by a sampling tube 6 with an NMR relaxometer 11, and a pipe 7 is installed in the sampling tube 6, which can move along the horse’s cross section expansion device 4. The entire device is placed in the housing 20.

The difference of the proposed device is that the conical expander 4 is located vertically, the measuring tube 1 has a cavity 2 sludge, and in the measuring tube 1, before the liquid flow enters the conical expander 4, a protective mesh 3 is installed, strain gauge pressure sensors 17 are installed in the conical expander 4 and in the cavity of the lower part of the conical expander 4 along the perimeter there are toothed rings 18, electromagnetic coils 8 for controlling the movement of the pipe 7 are placed on the sampling tube 6, while To move the nozzle 7 along the cross section of the conical expander 4 is carried out by the introduced controller 24, connected to electromagnetic coils 8.

In the housing 20 is a pipe 21 for discharging settled in the cavity 2 of mechanical impurities.

To measure the flow rate, the pipe 7 is located in a section that provides a flow rate for which the maximum steepness of the dependence of the effective relaxation rate on the flow rate of the liquid is obtained.

The flow rate ν _T or flow rate Q _T in the measuring tube 1 are determined respectively by the formulas:

where S _D and S are the cross-sectional areas, respectively, of the tube 13 of the NMR sensor and the conical expander 4 of the measuring tube 1 at the level of the position of the pipe 7, K = S _T / S _D is the reduction coefficient, K _C is the coefficient depending on Q _D = K _C S _D (T _2Eff ) ^-1 , (T _2Eff ) ^-1 = (T _2o ) ^-1 + (τ) ^-1 , T _2o is the relaxation time in a stationary liquid, τ is the residence time of the liquid in the NMR sensor. The costs Q _{i the} component of the liquid is determined by the formula:

where P _i is the concentration of the ith component of the mixture, determined from the decomposition into components of the envelope of the spin-echo of the NMR signal by values extrapolated to zero time.

The volumetric gas content V _G is determined by the formula:

where A ₀ , A _G are the initial amplitudes, respectively, when the NMR sensor is completely filled with crude oil and partially filled with gas.

Distinctive design features of the proposed device provide the following technical results.

The vertical arrangement of the conical expander 4 eliminates the possibility of delamination and the influence on the measurement of the incomplete filling of the tube 6 leading to the NMR relaxometer 11.

The presence in the measuring tube 1 of the cavity 2 provides the subsidence (sediment) of mechanical impurities.

Mesh 3 protects the pipe 7 from asphalt-resin inclusions and mechanical impurities.

To control the pressure in the conical expander 4 mounted strain gauge pressure sensors 17.

The placement of the gear rings 18 around the perimeter of the cavity of the lower part of the conical expander 4 creates effective turbulation and additional homogenization of the fluid flow, thereby achieving a higher sampling representativeness.

Monitoring and controlling the movement of the pipe 7 along the cross section of the conical expander 4 is carried out by the controller 24, while the measurement process is automated by controlling the position of the pipe 7 at a level corresponding to the maximum slope of the effective relaxation rate from the fluid flow rate.

A device for measuring the composition and flow rate of multicomponent liquids works as follows.

Previously, in a stopped fluid flow, when the pipe 7 is at the level of the cross section of the measuring pipe 1, i.e. the pressure drop (P _T -P _i ) is equal to zero, the concentration W of water in the liquid phase of the SCF is measured, which selects the dependence (T _2Eff ) ^-1 corresponding to a given concentration W on the velocity ν _i of the liquid flow and the optimal position of the nozzle 7. When measuring flow rate on command from the controller 23, the pipe 7 moves to a position corresponding to the maximum slope of the dependence (T _2Eff ) ^-1 on the velocity ν _i of the fluid flow.

The temperature of the flow in the tube 6 is measured by the temperature sensor 9. Next, the flow through the flanges 10 enters the magnet of the NMR relaxometer 11, namely, the gap of the pole pieces 12 through the non-magnetic tube 13, on which the inductor 14 is wound, from which the effective relaxation time T _{2Eff is determined} SKZh flow, which through flanges 15 enters the bend of the pipe 1 and then into the main pipe 19. The NMR signal is transmitted to the connector 16 and through the cable 22 with a length of a quarter of the resonant wave (λ / 4 = ν _o c, where c is the speed of light) to the receiver, to the controller and over the air to the dispatcher. The pressure P _i (and, accordingly, the component speeds ν _i ) is controlled by strain gauge pressure sensors 17 installed in a conical expander 4.

From the main pipe 19, the SCF stream enters the measuring pipe 1, in which mechanical impurities settle in the cavity 2 of the sludge. Then, through the protective grid 3, the fluid flow enters the conical expander 4, connected to the measuring tube 1 by the flanges 5. In the conical expander 4, turbulence and homogenization of the fluid flow occurs, which under the influence of the pressure drop (P _T -P _i ) in sections S _T and S _i flows into the tube 6 through a pipe 7 whose position is fixed current supplied to the electromagnetic coil 8. The temperature of the fluid flow in the tube 6 is measured by a temperature sensor 9. Next, flow of fluid through the flanges 10 relaxometer 11 enters the NMR magnet, namely the gap of the pole pieces 12 of a nonmagnetic tube 13 on which is wound a coil inductor 14, the signal which is determined by the effective relaxation time T _2Eff SCF flow which enters through the flanges 15 to the knee of the measuring tube 1 and further in the main pipe 19. The NMR signal is transmitted to connector 16 and cable 22, a quarter of the resonant wavelength (λ / 4 = ν _o c, where c is the speed of light), enters the transceiver 23, to the controller 24 and via the radio channel to the control point 25 of the dispatcher.

The movement of the nozzle 7 and the value of S is determined by the Atmega 851 SL controller 23 by its position, measured by the number of pulses from the shutter (not conventionally shown in the drawing).

The movement parameters are set from the interface window, similar to the Windows windows, front control panel on the control point 25 of the dispatcher.

To initialize the process of controlling the position of the pipe 7 according to the ratio of the liquid phases (water concentration W in the liquid), the computer (not shown conventionally in the drawing) selects from the pre-entered database the position of the pipe 7 corresponding to the maximum slope of the dependence (T _{2 Eff} ) ^-1 on speed ν _i . After that, the main drive control program is called on the main computer (not shown conventionally in the drawing). The VISA serial port is configured and the Start command is expected to enter the main subroutine for measuring the average flow rate Q _T and velocity ν _T of the SKZH flow according to formulas (1) and (2), as well as the costs Q _i of the SKZh component according to the formula (3) . To determine the flow velocity ν _i over the cross-section, it is necessary to determine the intermediate stop positions of the drive and the waiting time at each stop. The distance over which the pipe should move is always counted and accordingly set from the initial position in millimeters (mm), and the waiting time in seconds (s). The maximum distance by which the nozzle 7 can be moved in this design corresponds to 130 mm.

Using the proposed device for measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance will eliminate phase separation in the conical expander of the measuring tube and the possibility of clogging of the sampling pipe with asphalt-resin inclusions and mechanical impurities, will ensure efficient turbulation and homogenization of the fluid flow in the conical expander of the measuring pipes, as well as automation of the measurement process.

Claims (2)

1. A device for measuring the composition and flow rate of multicomponent liquids using the method of nuclear magnetic resonance (NMR), including an NMR relaxometer with a sensor having a tube for irradiating the liquid flow and receiving spin-echo NMR signals, which determine the parameters of the liquid, the sampling system, containing a measuring tube connected by a sampling tube with an NMR relaxometer, while the measuring tube has a conical expander, and a pipe is installed in the sampling tube that can be moved along the cross section of the conical expander, characterized in that the conical expander is located vertically in the measuring tube, a protective grid is installed in front of the liquid flow inlet to the conical expander, strain gauge pressure sensors are installed in the conical expander, and toothed rings are placed around the perimeter of the lower part of the conical expander , on the sampling tube there are electromagnetic coils for controlling the movement of the nozzle, while expanding the control of the movement of the nozzle along the conic section It is carried out by an input controller connected to electromagnetic coils. 2. A device for measuring the composition and flow rate of multicomponent fluids using the method of nuclear magnetic resonance according to claim 1, characterized in that for measuring the flow rate Q _{T the} nozzle is located in a section providing a flow rate for which the maximum slope of the dependence of the effective relaxation rate is obtained (T _2Eff ) ^-1 from the flow rate of the fluid, while the velocity ν _{T of the} flow and flow rate Q _T in the measuring tube is determined respectively by the formulas ν _T = K _C S [(T _2Eff ) ^-1 ] / KS _D and Q _T = K _C S (T _2Eff ) ^-1 , where S _D is the cross-sectional area of the tube d NMR relaxometer probe, S is the cross-sectional area of the conical expander at the level of the nozzle position, K = S _T / S _D is the reduction coefficient, K _C is the coefficient depending Q _D = K _C S _D (T _2Eff ) ^-1 , (T _2Eff ) ^-1 = (T _2o ) ^-1 + (τ) ^-1 , T _2o is the relaxation time in a stationary fluid, τ is the residence time of the fluid in the NMR sensor, and the flow rate Q _i of the fluid component is determined by the formula Q _i = Q · P _i where P _i is the concentration of the ith component of the mixture, determined from the expansion into the components of the envelope of the spin-echo of the NMR signal from the values extrapolated to zero time, volumetric gas content V _{G is} determined by the formula V _G = (A ₀ -A _G ) / A ₀ , where A ₀ , A _G are the initial amplitudes, respectively, when the NMR sensor is completely filled with crude oil and partially filled with gas.

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