High-temperature and high-pressure thickened oil-gas mixed fluid on-line viscosity detection device and method

Abstract

The application provides a high-temperature and high-pressure thickened oil and gas mixed fluid on-line viscosity detection device and method, and belongs to the technical field of oil and gas yield increase. The application comprises a circulating mechanism, a temperature control mechanism and a data acquisition and processing system. The circulating mechanism comprises a circulating pump, a high-temperature and high-pressure container, a dosing pump, a high-pressure reversing valve, an air compressor and a main pipeline. The high-temperature and high-pressure container and the main pipeline are connected with the high-pressure reversing valve. The dosing pump is used for injecting the liquid in the high-temperature and high-pressure container into the main pipeline. The air compressor is used for injecting gas into the main pipeline. The circulating pump and the high-pressure reversing valve make the oil and gas mixed fluid circulate. The data acquisition and processing system acquires and processes the physical parameters of the oil and gas mixed fluid in the main pipeline. The viscosity is calculated through the formula provided by the application, the pressure thickening and the thickened oil shear thinning characteristics are fully considered, the pressure and shear influencing factors are added, and the blank of the on-line viscosity real-time measurement of the thickened oil and gas two-phase mixed fluid under high-temperature and high-pressure is filled.

Description

Technical Field

[0001] This invention relates to the field of oil and gas production enhancement technology, and in particular to an online viscosity detection device and method for high-temperature and high-pressure heavy oil and gas mixtures. Background Technology

[0002] The flow of oil and gas two-phase mixtures is widely used in petroleum, chemical and other related industries. In particular, the flow of oil and gas two-phase mixtures is quite common in the petroleum industry, and the study of their flow laws is especially important.

[0003] Viscosity is a crucial physical parameter for measuring a liquid's ability to inhibit flow, and it is one of the important physical properties and technical indicators of liquids. The characteristics of a liquid are often related to other properties such as color, density, stability, solid content, and molecular weight changes. The most convenient and sensitive method for detecting these characteristics is online viscosity measurement. In physical chemistry, fluid mechanics, and other scientific fields, viscosity measurement plays a vital role in understanding fluid properties and studying flow states. With the continuous improvement of the national economy, the accurate determination of the viscosity of multiphase fluids is of great significance in many industrial sectors and scientific research fields, and the requirements for viscosity measurement are becoming increasingly prominent. In practical engineering and industrial production, online viscosity measurement of fluids is frequently required to ensure optimal process operating environment and product quality, thereby improving production efficiency, especially in industries such as petrochemicals, pharmaceuticals, metallurgy, and food. For example, during long-distance crude oil pipeline transportation, excessively high crude oil viscosity not only affects transportation efficiency but may also cause crude oil to condense and lead to accidents. By measuring the viscosity of gas-liquid mixtures online and obtaining data on liquid rheological behavior, it is of significant guiding value for predicting process control, transportability, and operability of products during use. With increasing demands for product quality control, traditional laboratory measurements or outdated inspections are no longer sufficient.

[0004] The viscosity of an oil-gas mixture is a measure of the frictional resistance generated when one part of the oil flows relative to another. It has a significant impact on oil and gas migration, accumulation, and oil and gas field development. Therefore, the measurement of the viscosity of the two phases of oil and gas is of great importance. Currently, most common viscometers use offline viscosity measurement methods, such as the vibration method, falling ball method, and rotation method. These methods require precise measurement of the temperature and viscosity of the liquid being measured. The principle is that the viscosity of a liquid increases as the temperature decreases; offline methods primarily measure the static viscosity-temperature properties of the fluid. Online viscosity measurement methods mainly use the capillary method, but capillary tubes are generally used for single-phase flow measurements and are inaccurate in describing the flow characteristics of multiphase fluids. Furthermore, they are poorly suited for crude oil, which has strong non-Newtonian properties, inevitably leading to significant errors and hindering industrial development.

[0005] The existing technology has at least the following shortcomings:

[0006] 1. The capillary method for online viscosity measurement is only applicable to single-phase flow measurement and is inaccurate in describing the flow characteristics of multiphase fluids;

[0007] 2. The capillary method for online viscosity measurement is poorly applicable to crude oil with strong non-Newtonian properties and has a large error. Summary of the Invention

[0008] To address the problems existing in the prior art, this invention provides an online viscosity detection device and method for high-temperature and high-pressure heavy oil-gas mixtures. The online viscosity detection device includes a circulation mechanism, a temperature control mechanism, and a data acquisition and processing system. The circulation mechanism includes a circulation pump, a high-temperature and high-pressure container, a dosing pump, a high-temperature and high-pressure intermediate container, a high-pressure reversing valve, an air compressor, a main pipeline, and a back-pressure valve. The high-temperature and high-pressure container and the main pipeline are both connected to the high-pressure reversing valve. The dosing pump is connected to the high-temperature and high-pressure intermediate container, which is connected to the main pipeline. The back-pressure valve is connected to the main pipeline and a sampling port. The dosing pump injects liquid from the high-temperature and high-pressure intermediate container into the main pipeline through an injection port. The air compressor provides a stable air source, which is injected into the main pipeline via a gas buffer tank and then into the high-temperature and high-pressure container. One end of the high-temperature and high-pressure container is connected to the circulation pump, and the output end of the container is connected to the data acquisition and processing system. The circulation pump and the high-pressure reversing valve work together to circulate the oil-gas mixture within the main pipeline. The temperature control mechanism is located between the high-temperature and high-pressure vessel and the data acquisition and processing system, and is used to control the temperature of the oil-gas mixture in the main pipeline. The data acquisition and processing system includes sensors and a control unit. The sensors measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit, which receives and processes the physical parameters. A formula for online viscosity detection of high-temperature and high-pressure heavy oil-gas mixtures by the control unit is given. This device and method fill the gap in real-time online viscosity measurement of heavy oil-gas two-phase mixtures under high temperature and high pressure. This method fully considers the characteristics of pressure-induced viscosity increase and shear-induced thinning of heavy oil, and adds influencing factors such as pressure and shear. It can measure the pipe flow viscosity of heavy oil-gas two-phase mixtures at different ratios in real time, study the viscosity change law during the dynamic mixing process of different fluids, and study the viscosity change law of heavy oil-gas two-phase mixtures with temperature and system pressure. It has a wide research range, with a measurement temperature up to 200℃ and a measurement pressure up to 70MPa.

[0009] This invention provides an online viscosity detection device for high-temperature and high-pressure heavy oil-gas mixtures, comprising: a circulation mechanism, a temperature control mechanism, and a data acquisition and processing system;

[0010] The circulation mechanism includes a circulation pump, a high-temperature and high-pressure vessel, a dosing pump, a high-temperature and high-pressure intermediate vessel, a high-pressure reversing valve, an air compressor, a main pipeline, and a back pressure valve; the main pipeline is made of high-temperature resistant materials such as stainless steel.

[0011] The high-temperature and high-pressure vessel and the main pipeline are both connected to the high-pressure reversing valve; the back pressure valve is connected to the main pipeline and the sampling port.

[0012] The dosing pump is connected to the high-temperature and high-pressure intermediate container, which is connected to the main pipeline. The dosing pump is used to inject the liquid in the high-temperature and high-pressure intermediate container into the main pipeline through the injection hole.

[0013] The air compressor is connected to the gas buffer tank, the gas buffer tank is connected to the main pipeline, and the main pipeline is connected to the high-temperature and high-pressure vessel.

[0014] The air compressor is used to provide a stable air source, which is injected into the main pipeline through the gas buffer tank, and then injected into the high-temperature and high-pressure container through the main pipeline. One end of the high-temperature and high-pressure container is connected to the circulation pump, and the output end of the high-temperature and high-pressure container is connected to the data acquisition and processing system.

[0015] The circulating pump and the high-pressure reversing valve work together to make the oil-gas mixture circulate in the main pipeline;

[0016] The temperature control mechanism is located between the high-temperature and high-pressure vessel and the data acquisition and processing system, and is used to control the temperature of the oil-gas mixture in the main pipeline;

[0017] The data acquisition and processing system includes sensors and a control unit. The sensors are used to measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit. The control unit receives the physical parameters and processes them.

[0018] Preferably, the temperature control mechanism includes an oil bath temperature controller, which is connected to the inlet of the data acquisition and processing system.

[0019] Preferably, all main pipes in the high-temperature and high-pressure heavy oil-gas mixture online viscosity testing device are equipped with a sleeve, the inside of the main pipe is used to contain the test fluid, and the oil bath temperature controller is used to heat the temperature-controlled fluid, so that the temperature-controlled fluid circulates between the sleeve and the main pipe.

[0020] Pipelines are also called oil pipes because the fluid flows in a circulating manner, so they are also called circulating oil pipes. Casings are also called circulating casings.

[0021] Preferably, the sensor includes a temperature sensor, a pressure sensor, and a differential pressure sensor, which are used to measure the system temperature, system pressure, and differential pressure at the test end, respectively.

[0022] Preferably, the control unit calculates the fluid viscosity in the pipeline based on the measured system pressure and the pressure difference at the test end.

[0023] Preferably, the control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters;

[0024]

[0025] in,

[0026] μ m The viscosity of the oil-gas mixture is expressed in mPa·s.

[0027] D is the inner diameter of the pipe section being measured, in meters (m).

[0028] v so The apparent flow rate of the oil is expressed in m / s.

[0029] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0030] P represents the operating pressure, measured in MPa.

[0031] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0032] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0033] g is the acceleration due to gravity;

[0034] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0035] b, c, and d are correction coefficients. The values ​​of each correction coefficient b, c, and d are determined based on the experimental results. The ranges of the correction coefficients b, c, and d are -50.13 to -61.22, c from 150.01 to 172.29, and d from -1.18 to -1.45, respectively.

[0036] This invention provides an online viscosity detection method for high-temperature, high-pressure heavy oil-gas mixtures, using the aforementioned online viscosity detection device for high-temperature, high-pressure heavy oil-gas mixtures. The main pipeline includes an oil phase and a gas phase, and the method comprises the following steps:

[0037] The sensor measures the physical parameters of the oil-gas mixture in the main pipeline and sends them to the control unit.

[0038] The control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters;

[0039]

[0040] in,

[0041] μ mThe viscosity of the oil-gas mixture is expressed in mPa·s.

[0042] D is the inner diameter of the pipe section being measured, in meters (m).

[0043] v so The apparent flow rate of the oil is expressed in m / s.

[0044] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0045] P represents the operating pressure, measured in MPa.

[0046] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0047] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0048] g is the acceleration due to gravity;

[0049] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0050] b, c, and d are correction coefficients. The values ​​of each correction coefficient b, c, and d are determined based on the experimental results. The ranges of the correction coefficients b, c, and d are -50.13 to -61.22, c from 150.01 to 172.29, and d from -1.18 to -1.45, respectively.

[0051] Preferably, the density of the oil-gas mixture is calculated using the following formula:

[0052] ρ m =(1-φ g )ρ o +φ g ρ g ;

[0053] in,

[0054] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0055] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0056] ρ g This refers to the gas phase density, expressed in g / cm³. 3 ;

[0057] Φg This represents the gas phase content.

[0058] Preferably, the gas phase content Φ is calculated using the following formula. g :

[0059]

[0060] in,

[0061] Φ g This refers to the gas phase content;

[0062] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0063] ρ g This refers to the gas phase density, expressed in g / cm³. 3 ;

[0064] σ1 is the interfacial tension between oil and gas, in N / m;

[0065] g is the acceleration due to gravity;

[0066] Q o Q g These represent the flow rates of the oil phase and the gas phase, respectively, in cubic meters per second (m³). 3 / s;

[0067] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0068] K3 and n are correction coefficients. The magnitudes of each correction coefficient K3 and n are determined by fitting a large amount of experimental data. The value ranges of correction coefficients K3 and n are 0.1 to 0.3 and 0.1 to 0.5, respectively.

[0069] Preferably, the correction coefficients b, c and d are as follows: b = -52.14, c = 160.39, d = -1.13, K3 = 0.157 and n = 0.32.

[0070] Preferably, when the gas-oil ratio is less than 10:1, the gas phase distribution factor c og The gas phase distribution factor c is 1.2 when the gas-oil ratio is 10:1 to 30:1. og The value is 1.62; when the gas-oil ratio is 30:1 to 60:1, the gas phase distribution factor c is... og The value is 2.23; when the gas-oil ratio is 60:1 to 90:1, the gas phase distribution factor c is... og The value is 2.45; when the gas-oil ratio is 90:1 to 120:1, the gas phase distribution factor c is... og It is 2.78.

[0071] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0072] (1) The high temperature and high pressure heavy oil-gas mixture online viscosity detection device of the present invention can be used to simulate actual industrial production conditions in the laboratory and simulate fluid flow environments with different temperatures and pressures. The entire device uses stainless steel pipes and is a fully enclosed circulation loop, which meets the requirements of high temperature and high pressure resistance. The entire device can withstand temperatures up to 200℃ and pressures up to 70MPa. The differential pressure sensor can measure up to 5MPa and measure viscosity up to 7000mPa·s, achieving a wide measurement range. Gas can be injected into the main pipeline through an air compressor and an air buffer tank to measure the viscosity of multiphase flow of oil and gas. Additives can be injected into the main pipeline through a dosing pump and a high temperature and high pressure intermediate container to measure the viscosity of the fluid with added additives.

[0073] (2) The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixture of the present invention combines physical simulation and mathematical modeling. It simulates the flow state of the oil-gas two-phase flow in a pipeline under high temperature and high pressure conditions, measures the flow pressure difference of the oil-gas two-phase fluid, and uses the measured pressure difference as a parameter to calculate the kinematic viscosity of the fluid using a viscosity calculation mathematical model. It employs mature and highly accurate conventional instruments for on-site signal detection, ensuring accurate and reliable measurement information. Conventional instruments refer to temperature, system pressure, and differential pressure sensors; the measurement accuracy should be within ±0.1% of the range to demonstrate high measurement accuracy.

[0074] (3) The data acquisition system of the high temperature and high pressure heavy oil-gas mixture online viscosity detection device of the present invention is equipped with a corresponding analysis model, which can detect the properties, flow resistance and viscosity changes of the fluid in the system in real time. It has high accuracy, fully meets the needs of crude oil mining, has low equipment investment, low cost and convenient installation and maintenance.

[0075] (4) In the viscosity calculation simulation of the high temperature and high pressure heavy oil-gas mixture online viscosity detection method of the present invention, correction coefficients K3 and n are added. These two parameters reflect the shear thinning characteristics of heavy oil and are applicable to non-Newtonian heavy oil-gas two-phase mixtures. When applied to multiphase fluid mechanics, only the values ​​of correction parameters a, b, c, d, e, k3, and n need to be modified. This provides technical guidance and theoretical support for actual production and can also be used to analyze the phase changes and flow friction of oil-gas two-phase fluids in pipelines. It also has important contribution value to the research of multiphase fluid mechanics. Attached Figure Description

[0076] Figure 1This is a schematic diagram of an online viscosity detection device for a high-temperature, high-pressure heavy oil-gas mixture according to an embodiment of the present invention. The dashed lines in the diagram represent heating circuits, which can be used to heat the oil-gas mixture to a high temperature.

[0077] Figure 2 This is a schematic diagram of the injection hole of a high-temperature and high-pressure container for injecting oil and gas according to an embodiment of the present invention. The upper vertical section and the middle horizontal section are the cross sections of the vertical and horizontal sections of the main pipeline, respectively, and the lower vertical section is connected to the gas buffer tank.

[0078] Figure 3 This is a cross-sectional schematic diagram of the casing and tubing according to an embodiment of the present invention.

[0079] In the picture:

[0080] 1-Dosing pump, 2-High temperature and high pressure intermediate container, 3-High pressure reversing valve, 4-Gas buffer tank, 5-Air compressor, 6-Main pipeline, 7-High temperature and high pressure container, 8-Casing, 9-Circulation pump, 10-Oil bath temperature controller, 11-Vacuum pump, 12-Sampling port, 13-Back pressure valve, 14-Data acquisition and processing system. Detailed Implementation

[0081] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0082] This invention provides an online viscosity detection device for high-temperature and high-pressure heavy oil-gas mixtures, comprising: a circulation mechanism, a temperature control mechanism, and a data acquisition and processing system;

[0083] The circulation mechanism includes a circulation pump 9, a high-temperature and high-pressure vessel 7, a dosing pump 1, a high-temperature and high-pressure intermediate vessel 2, a high-pressure reversing valve 3, an air compressor 5, a main pipeline 6, and a back pressure valve 13; the main pipeline 6 is made of high-temperature resistant materials such as stainless steel; the back pressure valve 13 is connected to the main pipeline 6 and the sampling port 12.

[0084] The back pressure valve 13 is used to sample the fluid inside the main pipeline 6 while maintaining high pressure. The oil bath temperature controller 10 is the temperature control mechanism. Figure 1 In the solid box, the main pipeline 6 and the data acquisition and processing system 14 are located. Oil enters the main pipeline 6 from the outlet of the high-temperature and high-pressure vessel 7, passes through the high-pressure reversing valve 3, and enters the test main pipeline 6 in the data acquisition and processing system 14. The oil circulates clockwise in the device, and after circulation, it enters the right end of the high-temperature and high-pressure vessel.

[0085] Both the high-temperature and high-pressure vessel 7 and the main pipeline 6 are connected to the high-pressure reversing valve 3.

[0086] The dosing pump 1 is connected to the high-temperature and high-pressure intermediate container 2, which is connected to the main pipeline 6. The dosing pump 1 is used to inject the liquid in the high-temperature and high-pressure intermediate container 2 into the main pipeline through the injection hole. The high-temperature and high-pressure intermediate container 2 contains chemicals, which typically include crude oil viscosity reducers and other liquids used to reduce the viscosity of crude oil. The dosing pump 1 injects the chemicals in the high-temperature and high-pressure intermediate container 2 into the main pipeline 6 to achieve mixing with the oil-gas mixture in the main pipeline 6.

[0087] Air compressor 5 is connected to gas buffer tank 4, gas buffer tank 4 is connected to main pipeline 6, and main pipeline 6 is connected to high temperature and high pressure vessel 7.

[0088] Air compressor 5 provides a stable air source, which is injected into the main pipeline 6 via gas buffer tank 4. The injection port for injecting gas has a diameter of 0.003m. The gas is then injected into high-temperature and high-pressure container 7 via the main pipeline 6. One end of high-temperature and high-pressure container 7 is connected to circulation pump 9. Circulation pump 9 injects liquid from high-temperature and high-pressure container 7 into the main pipeline 6 through the injection port. The liquid in high-temperature and high-pressure container 7 is petroleum. The injection port for injecting oil has a diameter of 0.01m. This injection port can also be used to inject other media, such as water.

[0089] The output terminal of the high-temperature and high-pressure vessel 7 is connected to a data acquisition and processing system;

[0090] The circulating pump 9 and the high-pressure reversing valve 3 work together to make the oil-gas mixture circulate in the main pipeline 6;

[0091] The temperature control mechanism is located between the high-temperature and high-pressure vessel 7 and the data acquisition and processing system, and is used to control the temperature of the oil-gas mixture in the main pipeline 6.

[0092] The data acquisition and processing system 14 includes sensors and a control unit. The sensors measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit, which receives and processes the physical parameters. Figure 1 The solid line box contains the main pipeline 6 and the data acquisition and processing system 14. Oil enters the main pipeline from the outlet of the high-temperature and high-pressure vessel, passes through the high-pressure reversing valve, and enters the test main pipeline in the data acquisition and processing system 14. The oil circulates clockwise in the device and enters the right end of the high-temperature and high-pressure vessel 7 after the circulation is completed.

[0093] According to a specific embodiment of the present invention, the temperature control mechanism includes an oil bath temperature controller 10, which is connected to the inlet of the data acquisition and processing system 14.

[0094] According to a specific embodiment of the present invention, all main pipes 6 in the high-temperature and high-pressure heavy oil-gas mixture online viscosity detection device are provided with a sleeve 8. The inside of the main pipe 6 is used to contain the test fluid, and the sleeve 8 and the main pipe 6 contain a temperature-controlled fluid. After the temperature-controlled fluid is heated to a specified temperature in the oil bath temperature controller 10, it is circulated between the sleeve 8 and the main pipe 6. The hot oil in the sleeve 8 then transfers the temperature to the test fluid in the main pipe 6.

[0095] According to a specific embodiment of the present invention, the sensor includes a temperature sensor, a pressure sensor, and a differential pressure sensor, which are used to measure the physical parameters of system temperature, system pressure, and differential pressure at the test end, respectively.

[0096] According to one specific embodiment of the present invention, the control unit calculates the viscosity of the fluid in the pipeline based on the measured system pressure and the pressure difference at the test end.

[0097] According to a specific embodiment of the present invention, the control unit calculates the fluid viscosity in the main pipeline based on the physical parameters using the following formula;

[0098]

[0099] in,

[0100] μ m The viscosity of the oil-gas mixture is expressed in mPa·s.

[0101] D is the inner diameter of the pipe section being measured, in meters (m).

[0102] v so The apparent flow rate of the oil is expressed in m / s.

[0103] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0104] P represents the operating pressure, measured in MPa.

[0105] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0106] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0107] g is the acceleration due to gravity;

[0108] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0109] b, c, and d are correction coefficients. The values ​​of each correction coefficient b, c, and d are determined based on the experimental results. The ranges of the correction coefficients b, c, and d are -50.13 to -61.22, c from 150.01 to 172.29, and d from -1.18 to -1.45, respectively.

[0110] This invention provides an online viscosity detection method for high-temperature, high-pressure heavy oil-gas mixtures, using the aforementioned online viscosity detection device for high-temperature, high-pressure heavy oil-gas mixtures. The main pipeline includes an oil phase and a gas phase, and the method comprises the following steps:

[0111] The sensor measures the physical parameters of the oil-gas mixture in the main pipeline and sends them to the control unit.

[0112] The control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters;

[0113]

[0114] in,

[0115] μ m The viscosity of the oil-gas mixture is expressed in mPa·s.

[0116] D is the inner diameter of the pipe section being measured, in meters (m).

[0117] v so The apparent flow rate of the oil is expressed in m / s.

[0118] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0119] P represents the operating pressure, measured in MPa.

[0120] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0121] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0122] g is the acceleration due to gravity;

[0123] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0124] b, c, and d are correction coefficients. The values ​​of each correction coefficient b, c, and d are determined based on the experimental results. The ranges of the correction coefficients b, c, and d are -50.13 to -61.22, c from 150.01 to 172.29, and d from -1.18 to -1.45, respectively.

[0125] In the viscosity calculation simulation of this invention, correction coefficients K3 and n are added. These two parameters reflect the shear thinning characteristics of heavy oil and are applicable to non-Newtonian heavy oil two-phase mixtures.

[0126] Under the same oil-gas ratio, when the oil phase is continuous, the flow pattern of the oil-gas two-phase flow changes from single-phase flow, bubbly flow, slug flow to slug flow, and the effective viscosity gradually increases. When the gas phase becomes continuous, the effective viscosity of the oil-gas two-phase flow decreases sharply. Therefore, by measuring the effective viscosity, the phase change of the heavy oil-gas two-phase fluid can be analyzed. At the same time, the effective viscosity can be substituted into the friction calculation model to calculate the flow friction.

[0127] When this viscosity calculation method is applied to multiphase fluid mechanics, only the values ​​of the correction parameters a, b, c, d, e, k3, and n need to be modified to make it applicable to heavy oil mixtures under different conditions.

[0128] According to a specific embodiment of the present invention, the density of the oil-gas mixture is calculated using the following formula:

[0129] ρ m =(1-φ g )ρ o +φ g ρ g ;

[0130] in,

[0131] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0132] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0133] ρ g This refers to the gas phase density, expressed in g / cm³. 3 ;

[0134] Φ g This represents the gas phase content.

[0135] According to a specific embodiment of the present invention, the gas phase holdup Φ is calculated using the following formula. g :

[0136]

[0137] in,

[0138] Φ g This refers to the gas phase content;

[0139] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0140] ρ g This refers to the gas phase density, expressed in g / cm³. 3 ;

[0141] σ1 is the interfacial tension between oil and gas, in N / m;

[0142] g is the acceleration due to gravity;

[0143] Q o Q g These represent the flow rates of the oil phase and the gas phase, respectively, in cubic meters per second (m³). 3 / s;

[0144] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0145] K3 and n are correction coefficients. The values ​​of each correction coefficient K3 and n were determined based on fitting a large amount of experimental data. The range of correction coefficients K3 and n is 0.1 to 0.3 and 0.1 to 0.5, respectively. After correction, the calculated final gas holdup can be more applicable to heavy oil with strong non-Newtonian characteristics.

[0146] According to a specific embodiment of the present invention, the correction coefficients b, c and d are as follows: b is -52.14, c is 160.39, d is -1.13, K3 is 0.157 and n is 0.32.

[0147] According to a specific embodiment of the present invention, when the gas-oil ratio is less than 10:1, the gas phase distribution factor c og The gas phase distribution factor c is 1.2 when the gas-oil ratio is 10:1 to 30:1. og The value is 1.62; when the gas-oil ratio is 30:1 to 60:1, the gas phase distribution factor c is... og The value is 2.23; when the gas-oil ratio is 60:1 to 90:1, the gas phase distribution factor c is... og The value is 2.45; when the gas-oil ratio is 90:1 to 120:1, the gas phase distribution factor c is... og It is 2.78.

[0148] Example 1

[0149] According to a specific embodiment of the present invention, the online viscosity detection device for high-temperature and high-pressure heavy oil-gas mixture of the present invention will be described in detail with reference to the accompanying drawings.

[0150] The circulation mechanism includes a circulation pump 9, a high-temperature and high-pressure vessel 7, a dosing pump 1, a high-temperature and high-pressure intermediate vessel 2, a high-pressure reversing valve 3, an air compressor 5, a main pipeline 6, and a back pressure valve 13; the main pipeline 6 is made of high-temperature resistant materials such as stainless steel.

[0151] The high-temperature and high-pressure vessel 7 and the main pipeline 6 are both connected to the high-pressure reversing valve 3; the back pressure valve 13 is connected to the main pipeline 6 and the sampling port 12.

[0152] The dosing pump 1 is connected to the high-temperature and high-pressure intermediate container 2, which is connected to the main pipeline 6. The dosing pump 1 is used to inject the liquid in the high-temperature and high-pressure intermediate container 2 into the main pipeline 6 through the injection hole.

[0153] Air compressor 5 is connected to gas buffer tank 4, gas buffer tank 4 is connected to main pipeline 6, and main pipeline 6 is connected to high temperature and high pressure vessel 7.

[0154] Air compressor 5 is used to provide a stable air source, which is injected into the main pipeline 6 through gas buffer tank 4, and then injected into high temperature and high pressure container 7 through the main pipeline 6. One end of high temperature and high pressure container 7 is connected to circulation pump 9, and the output end of high temperature and high pressure container 7 is connected to data acquisition and processing system.

[0155] The circulating pump 9 and the high-pressure reversing valve 3 work together to make the oil-gas mixture circulate in the main pipeline 6;

[0156] The temperature control mechanism is located between the high-temperature and high-pressure vessel 7 and the data acquisition and processing system 14, and is used to control the temperature of the oil-gas mixture in the main pipeline 6.

[0157] The data acquisition and processing system 14 includes a sensor and a control unit. The sensor is used to measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit. The control unit receives the physical parameters and processes them.

[0158] Example 2

[0159] According to a specific embodiment of the present invention, the online viscosity detection device for high-temperature and high-pressure heavy oil-gas mixture of the present invention will be described in detail with reference to the accompanying drawings.

[0160] The circulation mechanism includes a circulation pump 9, a high-temperature and high-pressure vessel 7, a dosing pump 1, a high-temperature and high-pressure intermediate vessel 2, a high-pressure reversing valve 3, an air compressor 5, a main pipeline 6, and a back pressure valve 13; the main pipeline 6 is made of high-temperature resistant materials such as stainless steel.

[0161] The high-temperature and high-pressure vessel 7 and the main pipeline 6 are both connected to the high-pressure reversing valve 3; the back pressure valve 13 is connected to the main pipeline 6 and the sampling port 12.

[0162] The dosing pump 1 is connected to the high-temperature and high-pressure intermediate container 2, which is connected to the main pipeline 6. The dosing pump 1 is used to inject the liquid in the high-temperature and high-pressure intermediate container 2 into the main pipeline 6 through the injection hole.

[0163] Air compressor 5 is connected to gas buffer tank 4, gas buffer tank 4 is connected to main pipeline 6, and main pipeline 6 is connected to high temperature and high pressure vessel 7.

[0164] Air compressor 5 is used to provide a stable air source, which is injected into the main pipeline through gas buffer tank 4 and into high temperature and high pressure container 7 through main pipeline 6. One end of high temperature and high pressure container 7 is connected to circulation pump 9, and the output end of high temperature and high pressure container 7 is connected to data acquisition and processing system 14.

[0165] The circulating pump 9 and the high-pressure reversing valve 3 work together to make the oil-gas mixture circulate in the main pipeline 6;

[0166] The temperature control mechanism is located between the high-temperature and high-pressure container 7 and the data acquisition and processing system 14, and is used to control the temperature of the oil-gas mixture in the main pipeline 6. The temperature control mechanism includes an oil bath temperature controller 10, which is connected to the inlet of the data acquisition and processing system 14. All the main pipelines 6 in the high-temperature and high-pressure heavy oil-gas mixture online viscosity detection device are provided with a sleeve 8. The inside of the main pipeline 6 is used to contain the test fluid. The oil bath temperature controller 10 is used to heat the temperature control fluid, so that the temperature control fluid circulates between the sleeve 8 and the main pipeline 6.

[0167] The data acquisition and processing system 14 includes sensors and a control unit. The sensors are used to measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit. The control unit receives the physical parameters and processes them. The sensors include a temperature sensor, a pressure sensor, and a differential pressure sensor, which are used to measure the system temperature, system pressure, and differential pressure at the test end, respectively. The control unit calculates the viscosity of the fluid in the pipeline based on the measured system pressure and differential pressure at the test end.

[0168] The control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters;

[0169]

[0170] in,

[0171] μ m The viscosity of the oil-gas mixture is expressed in mPa·s.

[0172] D is the inner diameter of the pipe section being measured, in meters (m).

[0173] v so The apparent flow rate of the oil is expressed in m / s.

[0174] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0175] P represents the operating pressure, measured in MPa.

[0176] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0177] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0178] g is the acceleration due to gravity;

[0179] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0180] b, c, and d are correction coefficients. The values ​​of each correction coefficient (b, c, and d) were determined based on experimental results. The ranges for correction coefficients b, c, and d are: b = -50.13 to -61.22, c = 150.01 to 172.29, and d = -1.18 to -1.45.

[0181] Example 3

[0182] According to a specific embodiment of the present invention, and in conjunction with the accompanying drawings, the online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures of the present invention will be described in detail using the online viscosity detection device for high-temperature and high-pressure heavy oil-gas mixtures of the present invention.

[0183] This invention provides an online viscosity detection method for high-temperature, high-pressure heavy oil-gas mixtures. Using the online viscosity detection device for high-temperature, high-pressure heavy oil-gas mixtures described in this invention, the main pipeline 6 includes an oil phase and a gas phase, and the method comprises the following steps:

[0184] The sensor measures the physical parameters of the oil-gas mixture in the main pipeline 6 and sends them to the control unit.

[0185] The control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters;

[0186]

[0187] in,

[0188] μ m The viscosity of the oil-gas mixture is expressed in mPa·s.

[0189] D is the inner diameter of the pipe section being measured, in meters (m).

[0190] v so The apparent flow rate of the oil is expressed in m / s.

[0191] ΔP is the pressure difference per unit length between the two ends of the measured pipe section, and the unit is Pa / m;

[0192] P represents the operating pressure, measured in MPa.

[0193] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0194] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0195] g is the acceleration due to gravity;

[0196] c og This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio.

[0197] b, c, and d are correction coefficients. The values ​​of each correction coefficient (b, c, and d) are determined based on experimental results. The ranges for correction coefficients b, c, and d are: b = -50.13 to -61.22, c = 150.01 to 172.29, and d = -1.18 to -1.45. Specifically, in this embodiment, the correction coefficients b, c, and d are: b = -52.14, c = 160.39, and d = -1.13.

[0198] The density ρ of the oil-gas mixture is calculated using the following formula. m :

[0199] ρ m =(1-φ g )ρ o +φ g ρ g ;

[0200] in,

[0201] ρ m The density of the oil-gas mixture is expressed in g / cm³. 3 ;

[0202] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0203] ρ g This refers to the gas phase density, expressed in g / cm³.3 ;

[0204] Φ g This represents the gas phase content.

[0205] The gas phase content Φ is calculated using the following formula. g :

[0206]

[0207] in,

[0208] Φ g This refers to the gas phase content;

[0209] ρ o This is the density of the oil phase, in g / cm³. 3 ;

[0210] ρ g This refers to the gas phase density, expressed in g / cm³. 3 ;

[0211] σ1 is the interfacial tension between oil and gas, in N / m;

[0212] g is the acceleration due to gravity;

[0213] Q o Q g These represent the flow rates of the oil phase and the gas phase, respectively, in cubic meters per second (m³). 3 / s;

[0214] c og The gas phase distribution factor (Cg) ranges from 1.2 to 2.78, with different values ​​depending on the gas-oil ratio. Specifically, in this embodiment, the gas phase distribution factor is determined using the following method: when the gas-oil ratio is less than 10:1, the gas phase distribution factor Cg... og The gas phase distribution factor c is 1.2 when the gas-oil ratio is 10:1 to 30:1. og The value is 1.62; when the gas-oil ratio is 30:1 to 60:1, the gas phase distribution factor c is... og The value is 2.23; when the gas-oil ratio is 60:1 to 90:1, the gas phase distribution factor c is... og The value is 2.45; when the gas-oil ratio is 90:1 to 120:1, the gas phase distribution factor c is... og It is 2.78.

[0215] K3 and n are correction coefficients. The values ​​of each correction coefficient K3 and n are determined based on fitting a large amount of experimental data. The range of correction coefficients K3 and n is K3 from 0.1 to 0.3 and n from 0.1 to 0.5, respectively. Specifically, in this embodiment, the correction coefficients K3 and n are K3 = 0.157 and n = 0.32, respectively.

[0216] Example 4

[0217] According to a specific embodiment of the present invention, in conjunction with the appendix Figure 1 The following describes the usage of this high-temperature, high-pressure heavy oil-gas mixture online viscosity detection device.

[0218] Figure 1 The main pipeline and data acquisition and processing system are implemented within the frame. The data acquisition and processing system includes sensors and control units. The control units include multiple control valves, multiple valves, and a pipeline periscope inspection instrument QV. The control valves are represented by "EV" and are used for measurement. The valves are represented by "V". V1 is used to open and close the vacuum pump, and V2 is used to open and close the sampling pump.

[0219] The sensors include a first pressure sensor P1 (P1 is the measured cyclic pressure), a second pressure sensor P2, a third pressure sensor P3, a first differential pressure sensor ΔP1 and a second differential pressure sensor ΔP2, and a first temperature sensor T1 and a second temperature sensor T2.

[0220] Preliminary preparations:

[0221] Prepare a two-phase oil-gas mixture sample with the required gas-oil ratio in a high-temperature and high-pressure container. Close EV2 and QV, open all other control valves and valves, open valve V1, and evacuate the system through the vacuum port.

[0222] After vacuuming is completed, set the pressure of back pressure valve 13 to the test pressure, open EV2 and QV, and pump the sample in high temperature and high pressure container 7 into the entire wellbore flow model system through circulation pump 9, and continue to pressurize until the pressure of the entire system reaches the actual production pressure to be simulated. At the same time, turn on oil bath temperature controller 10, set the temperature to be simulated under the actual production conditions, and stabilize for a period of time until the temperature sensor in the system shows that the set temperature has been reached.

[0223] Based on the flow rate under the actual production conditions to be simulated, a certain flow rate is set for the circulating pump 9, causing the oil-gas two-phase mixed fluid sample to circulate clockwise or counterclockwise along the main pipeline 6. After the circulation stabilizes for a certain period of time, the readings of the differential pressure sensor and the pressure sensor (i.e., the readings of the first pressure sensor P1 (P1 is the measured circulating pressure), the second pressure sensor P2, and the differential pressure sensor ΔP) are read. If the fluid viscosity is high and the differential pressure through the measuring pipe section is greater than the range of the differential pressure sensor, control valves EV7 and EV8 can be closed. The differential pressure is calculated by the pressure sensors at the inlet and outlet of the measuring section, and the current fluid viscosity is automatically calculated by the data processing system.

[0224] If sampling is required during fluid circulation, the pressure set on the back pressure valve 13 can be slightly reduced (the reduction should not exceed 0.5 MPa), and valve V2 can be opened for sampling.

[0225] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for online viscosity detection of high-temperature, high-pressure heavy oil-gas mixtures, using a high-temperature, high-pressure heavy oil-gas mixture online viscosity detection device, characterized in that... The main pipeline contains both an oil phase and a gas phase; The high-temperature and high-pressure heavy oil-gas mixture online viscosity detection device includes: a circulation mechanism, a temperature control mechanism, and a data acquisition and processing system; The circulation mechanism includes a circulation pump, a high-temperature and high-pressure vessel, a dosing pump, a high-temperature and high-pressure intermediate vessel, a high-pressure reversing valve, an air compressor, a main pipeline, and a back pressure valve. The high-temperature and high-pressure vessel and the main pipeline are both connected to the high-pressure reversing valve. The dosing pump is connected to the high-temperature and high-pressure intermediate container, the high-temperature and high-pressure intermediate container is connected to the main pipeline, and the back pressure valve is connected to the main pipeline and the sampling port. The air compressor is connected to the gas buffer tank, the gas buffer tank is connected to the main pipeline, the main pipeline is connected to the high-temperature and high-pressure vessel, one end of the high-temperature and high-pressure vessel is connected to the circulation pump, and the output end of the high-temperature and high-pressure vessel is connected to the data acquisition and processing system. The circulating pump and the high-pressure reversing valve work together to make the oil-gas mixture circulate in the main pipeline; The temperature control mechanism is located between the high-temperature and high-pressure vessel and the data acquisition and processing system, and is used to control the temperature of the oil-gas mixture in the main pipeline; The data acquisition and processing system includes sensors and a control unit. The sensors are used to measure the physical parameters of the oil-gas mixture in the main pipeline and send them to the control unit. The control unit receives the physical parameters and processes them. Includes the following steps: The sensor measures the physical parameters of the oil-gas mixture in the main pipeline and sends them to the control unit. The control unit calculates the fluid viscosity in the main pipeline using the following formula based on the physical parameters; in, μm The viscosity of the oil-gas mixture is expressed in mPa·s. D The inner diameter of the pipe section being measured is in meters (m). VSO The apparent flow rate of the oil is expressed in m / s. ΔP The pressure difference per unit length between the two ends of the measured pipe section is expressed in Pa / m. P Operating pressure, in MPa; ρm The density of the oil-gas mixture, in units of ; ρo This is the density of the oil phase, in units of... ; g It is the acceleration due to gravity; cog This is the gas phase distribution factor, with a value ranging from 1.2 to 2.78, depending on the gas-oil ratio. b, c, and d are correction coefficients. The values ​​of each correction coefficient b, c, and d are determined based on the experimental results. The ranges of the correction coefficients b, c, and d are -50.13 to -61.22, c is 150.01 to 172.29, and d is -1.18 to -1.45, respectively. The density of the oil-gas mixture is calculated using the following formula: ； in, ρg This is the gas phase density, in units of... ; Φg This refers to the gas phase content; The gas phase holdup is calculated using the following formula. Φg : ； in, σ 1 represents the interfacial tension between oil and gas, in N / m. Qo , Qg These represent the flow rates of the oil phase and the gas phase, respectively, in cubic meters per second (m³). 3 / s; K3 and n These are correction coefficients, determined by fitting experimental data. K3 and n Size, correction factor K3 and n The range of values ​​are respectively K3 The value is 0.1~0.

3. n It ranges from 0.1 to 0.

5.

2. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 1, characterized in that, The correction factors are as follows: b = -52.14, c = 160.39, and d = -1.

13. K3 It is 0.

157. n It is 0.

32.

3. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 1, characterized in that, When the gas-oil ratio is less than 10:1, the gas phase distribution factor is... cog The gas phase distribution factor is 1.2 when the gas-oil ratio is 10:1 to 30:

1. cog The value is 1.62; when the gas-oil ratio is 30:1 to 60:1, the gas phase distribution factor is... cog The value is 2.23; when the gas-oil ratio is 60:1~90:1, the gas phase distribution factor is... cog The value is 2.45; when the gas-oil ratio is 90:1~120:1, the gas phase distribution factor is... cog It is 2.

78.

4. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 1, characterized in that, The temperature control mechanism includes an oil bath temperature controller, which is connected to the inlet of the data acquisition and processing system.

5. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 4, characterized in that, In the online viscosity testing device for high-temperature and high-pressure heavy oil-gas mixture, all main pipelines are equipped with a sleeve. The inside of the main pipeline is used to contain the test fluid, and the oil bath temperature controller is used to heat the temperature-controlled fluid, so that the temperature-controlled fluid circulates between the sleeve and the main pipeline.

6. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 1, characterized in that, The sensors include a temperature sensor, a pressure sensor, and a differential pressure sensor.

7. The online viscosity detection method for high-temperature and high-pressure heavy oil-gas mixtures according to claim 6, characterized in that, The control unit calculates the viscosity of the fluid in the pipeline based on the measured system pressure and the pressure difference at the test end.

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