CN205607955U - CO2 solubility and foaming stabilization testing arrangement in crude oil - Google Patents

Abstract

A test device for the solubility of _CO2 in crude oil and foam stability, including a gas injection part, an inlet pressure control part, a foam test part and an outlet pressure control part, through the combined adjustment of the two-stage valves in the inlet pressure control part, the transparent reactor can be precisely controlled The temperature of the transparent reaction kettle can be precisely controlled by using the constant temperature water bath and the circulating water between the transparent water jacket, and the gas flow meter can be used to accurately measure the volume of _CO2 injected into the transparent reaction kettle, and then the crude oil under the conditions of the set temperature and pressure can be obtained. Solubility of _CO2 . The transparent reactor cylinder is made of transparent material to realize the visual observation of the stable state of the foam. The utility model can simulate the actual separation process of dissolved gas crude oil, can test and evaluate the dissolution characteristics of _CO2 in crude oil and the stability characteristics of _CO2 foam under different temperature and pressure conditions, has the advantages of precise control and accurate measurement, and realizes The optimization of the key parameters of the separation process provides a basis for the optimal design and efficient operation of the separation equipment.

Description

A testing device for CO2 solubility and foam stability in crude oil

technical field

The utility model relates to a _CO2 solubility and foam stability testing device in crude oil, which is used for testing and evaluating the solubility characteristics of _CO2 in crude oil and the stability characteristics of _CO2 foam under different temperature and pressure conditions. The utility model belongs to the technical field of multiphase separation of oil and gas gathering and transportation systems.

Background technique

As a mature oil recovery technology, CO ₂ flooding technology is gradually adopted in the development of oilfields at home and abroad. Oilfield development practice shows that CO ₂ flooding technology is an effective means to enhance oil recovery, reduce production cost and store CO ₂ . However, a large amount of CO ₂ gas is dissolved in the crude oil produced by this technology, which will easily cause the crude oil to foam and form a stable foam, resulting in the inability of the separation equipment to separate effectively, resulting in the failure of the entire gathering and transportation system to operate normally.

The solubility of _CO2 gas in crude oil is high, but the physical and chemical properties of different crude oils are quite different, and the amount of _CO2 dissolved cannot be accurately predicted. Therefore, it is necessary to test the solubility characteristics of _CO2 in crude oil to provide a basis for process optimization of gathering and transportation systems parameter. At the same time, in order to effectively remove _CO2 gas in crude oil and improve the efficiency of separation equipment, it is necessary to test the stability characteristics of _CO2 foam to provide a basis for the design and operation of separation equipment.

The difference between the existing foam stability evaluation methods is mainly reflected in two aspects: foaming mode and evaluation index. Foaming methods can be divided into two types according to different principles. One is to mix air bubbles in the liquid by inflating, dispersing or disturbing the liquid, such as airflow method, Ross-Miles method and Warning Blender method; The gas and liquid are decompressed to form bubbles. At the same time, the physical and chemical properties of dissolved air crude oil are greatly affected by pressure and temperature, and the evaluation method of foam stability under normal temperature and pressure cannot truly reflect the characteristics of foam under actual temperature and pressure. The device of the utility model can accurately test and evaluate the stability characteristics of the _CO2 foam in the depressurization process of the dissolved gas crude oil.

For evaluation indicators of foam stability, scholars at home and abroad have defined parameters such as foam half-life, foam comprehensive index, and foam comprehensive performance indicators. Chinese patent 201410724298.0 (authorized patent announcement number CN 104502059 A) discloses a foam stability test under pressure fluctuations Device and working method, the patent evaluates the foam characteristics with the liquid discharge volume. US Patent 5853618 (Granted Patent Publication No. US 005853618A) has invented a foam preparation method, and the foam performance is defined by the half-life of the foam volume. These two patents do not consider the influence of the liquid phase volume on the foam volume, and the utility model uses the relative foam volume as an index to analyze the total decay time of the foam.

In order to simulate the gas-liquid separation process of _CO2 foamed crude oil in the actual production process, it is necessary to invent a set of test equipment, which can reproduce the gas-dissolving process of crude oil under a certain pressure and temperature, and measure the solubility of _CO2 in crude oil ; At the same time, it can simulate the actual production process of the gathering and transportation system, and evaluate the stability characteristics of CO ₂ foam in the dissolved gas; realize the optimization of the key parameters of the separation process, and provide a basis for the optimal design and efficient operation of the separation equipment.

Contents of the invention

The utility model provides a CO ₂ solubility and foam stability testing device in crude oil, which can test the solubility characteristics of CO ₂ in crude oil under different temperature and pressure conditions, and can test CO ₂ foam under different temperature, pressure and decompression rate conditions. The stable characteristics solve the test problems of _CO2 solubility and foam stability in the actual production process. The test results of the test device can be used as a reference for the design and operation of the separation equipment of the gathering and transportation system.

The utility model also provides a test method of the above-mentioned test device. The test method uses the relative volume of the foam as the foam performance index, and can obtain the complete change trend of the relative volume of the foam in the time dimension, and can more accurately evaluate the stability of the _CO2 foam. characteristic.

A kind of _{CO2solubility} and foam stability testing device in crude oil, it is characterized in that, comprise gas cylinder, on the outlet pipeline of gas cylinder, gas cylinder decompression valve and first valve are installed successively, and described first valve respectively Connect the second valve and the inlet pressure regulating valve, the other end of the second valve communicates with the top of the vacuum container, the top of the vacuum container is provided with a vacuum gauge and a vacuum pump, and the bottom is also provided with a third valve; the inlet pressure regulating valve The other end of the valve is connected to the transparent reaction kettle through the fourth valve, the inlet gas flowmeter and the fifth valve in sequence; between the inlet pressure regulating valve and the transparent reaction kettle, there is also a connection with the above-mentioned fourth valve, the inlet gas flowmeter, The fifth valve is connected in parallel with the bypass valve——the sixth valve; the transparent reactor includes a transparent cylinder marked with a scale on the outer wall, and the upper and lower ends of the cylinder are respectively provided with a top cover and a bottom cover. There is a transparent water jacket, the transparent water jacket is connected with the constant temperature water bath, and the circulating water circulates between the transparent water jacket and the constant temperature water bath to keep the temperature of the transparent reactor constant; the bottom cover and the top cover of the transparent reactor are respectively equipped with temperature sensors and gas outlets , wherein the gas outlet communicates with the pressure sensor, the top cover of the transparent reaction kettle is also provided with a stirring motor, the stirring shaft of the stirring motor is located inside the transparent cylinder, and the stirring shaft is provided with a stirring paddle; the constant temperature water bath, temperature sensor, pressure The sensor and the stirring motor are respectively connected with the control box; the gas outlet of the top cover of the transparent reaction kettle is also connected with the outlet back pressure valve through the seventh valve, the outlet gas flowmeter, and the eighth valve in turn, and the gas in the top cover of the transparent reaction kettle Between the outlet and the outlet back pressure valve, there is also a bypass valve, the ninth valve, connected in parallel with the seventh valve, the outlet gas flow meter and the eighth valve.

The bottom cover of the transparent reaction kettle is also provided with an emptying port.

A testing device for _CO2 solubility and foam stability in crude oil, characterized in that it includes a gas injection unit, an inlet pressure control unit, a foam test unit and an outlet pressure control unit, and the parts are connected in series in sequence.

The gas injection part includes a gas cylinder connected in sequence along the gas flow direction, a gas cylinder decompression valve and a first valve, and a second valve and a vacuum container are arranged in parallel with the first valve; the top of the vacuum container is connected with a vacuum Gauge and vacuum pump with a third valve connected at the bottom.

The inlet pressure regulating part includes an inlet pressure regulating valve, a fourth valve, an inlet gas flowmeter, a fifth valve and a sixth valve. The pipeline where the sixth valve is located and the pipeline where the fourth valve, the inlet gas flowmeter and the fifth valve are located form a parallel pipeline.

The foam test section includes a transparent reactor and a control box; the transparent reactor includes a reactor cylinder, a reactor bottom cover and a reactor top cover, and a transparent water jacket is arranged on the outside of the reactor cylinder, and the The transparent water jacket and the constant temperature water bath form a circulation loop; the bottom cover of the reaction kettle is provided with a temperature sensor; the top cover of the reaction kettle is provided with a pressure sensor and a stirring part, and the stirring part is provided with a motor, a stirring shaft and a stirring paddle.

The outlet pressure regulating part includes a seventh valve, an outlet gas flow meter, an eighth valve, a ninth valve and an outlet back pressure valve. The pipeline where the ninth valve is located and the pipeline where the seventh valve, the outlet gas flowmeter and the eighth valve are located form a parallel pipeline.

The working process of the utility model is that the vacuum pump sucks the dissolved gas in the crude oil and the air in the transparent reaction kettle, the gas cylinder provides _CO2 gas, the joint adjustment of the gas cylinder decompression valve and the two-stage valve realizes pressure control, and the transparent water jacket The circulating water realizes temperature control, and multiple pressure adjustments realize the dissolution balance of crude oil and _CO2 gas under a certain temperature and pressure. The cumulative flow rate of the inlet gas flowmeter minus the gas volume in the transparent reactor is the volume of dissolved _CO2 gas in crude oil under certain temperature and pressure conditions. The joint adjustment of the outlet two-stage valve realizes the control of the depressurization rate. The crude oil and foam are observed through the transparent reactor, and the volume of the foam relative to the crude oil is selected as an index to evaluate the stability of the _CO2 foam under a certain temperature, pressure and depressurization rate.

The basic principle of the utility model is that the dissolved _CO2 gas in the crude oil precipitates bubbles as the pressure drops, and the bubbles rise from the inside of the crude oil to the liquid surface, and the bubbles will not burst immediately, but will burst after a certain period of time. Therefore the total volume of crude oil and foam will go through a process of increasing to a maximum value and then decreasing to the initial volume. In this process, the stability characteristics of the _CO2 foam can be accurately evaluated by using the volume of the foam relative to the crude oil as an index.

The beneficial effect of the utility model is that it can accurately measure the solubility of _CO2 in crude oil under different temperature and pressure conditions, and accurately evaluate the stability characteristics of _CO2 foam under different temperature, pressure and decompression rate conditions. The dissolved gas in the crude oil and the air in the transparent reactor are sucked by a vacuum pump to increase the measurement accuracy. The gas injection process of the transparent reactor can be precisely controlled through the combined adjustment of the pressure reducing valve of the gas cylinder and the two-stage valve of the inlet pressure control part; the accurate measurement of the solubility of _CO2 in crude oil under different temperature and pressure conditions is realized through the inlet gas flow meter. The transparent reactor realizes the visual observation of the stable state of the foam under various working conditions, and the circulating water in the transparent water jacket ensures the precise control of the temperature of the transparent reactor. The pressure drop rate of the transparent reactor can be precisely controlled through the joint adjustment of the two-stage valve of the outlet pressure control part. Using the relative foam volume to analyze the total decay time of the foam can obtain the complete change trend of the relative volume of the foam in the time dimension, and can more accurately evaluate the stability characteristics of the CO ₂ foam.

Description of drawings

Fig. 1 is a flowchart of the utility model.

Among them, 1—gas cylinder 2—gas cylinder pressure reducing valve 3—first valve 4—second valve 5—vacuum container 6—vacuum gauge 7—vacuum pump 8—third valve 9—inlet pressure regulating valve 10—fourth valve 11—Inlet gas flow meter 12—Fifth valve 13—Sixth valve 14—Transparent reactor 15—Transparent water jacket 16—Constant temperature water bath 17—Temperature sensor 18—Pressure sensor 19—Motor 20—Stirring shaft 21—Stirring paddle 22 - control box 23 - seventh valve 24 - outlet gas flow meter 25 - eighth valve 26 - ninth valve 27 - outlet back pressure valve.

Fig. 2 is the structural diagram of the utility model transparent reactor.

Among them, 15—transparent water jacket 17—temperature sensor 18—pressure sensor 19—stirring motor 20—stirring shaft 21—stirring paddle 28—circulating water bath outlet 29—circulating water bath inlet 30—evacuation port 31—gas outlet.

detailed description

As shown in Figures 1 and 2, the utility model comprises: a gas cylinder (1), a gas cylinder decompression valve (2), a first valve (3), a second valve (4), a vacuum container (5), a vacuum gauge (6 ), vacuum pump (7), third valve (8), inlet pressure regulating valve (9), fourth valve (10), inlet gas flow meter (11), fifth valve (12), sixth valve (13) , transparent reaction kettle (14), transparent water jacket (15), constant temperature water bath (16), temperature sensor (17), pressure sensor (18), motor (19), stirring shaft (20), stirring paddle (21), Control box (22), seventh valve (23), outlet gas flowmeter (24), eighth valve (25), ninth valve (26), outlet back pressure valve (27), circulating water bath outlet (28), Circulating water bath inlet (29), emptying port (30), gas outlet (31), etc.

A gas cylinder decompression valve (2) is installed behind the gas cylinder (1). The first valve (3) is installed behind the gas cylinder decompression valve (2), and can cut off the gas supply of the gas cylinder. The vacuum pump (7) can suck the dissolved gas in the crude oil and the air in the transparent reactor (14), and the vacuum gauge (6) can indicate the degree of vacuum in the vacuum container (5). The inlet and outlet of the vacuum container (5) are controlled by the second valve (4) and the third valve (8) respectively.

The inlet pressure regulating valve (9) is jointly adjusted with the fourth valve (10) and the fifth valve (12) to control the gas cylinder to inject gas into the transparent reaction kettle; the inlet gas flow meter (11) measures the gas flow through the pipeline. Gas volume; the sixth valve (13) is a bypass valve.

The cylinder body of the transparent reaction kettle (14) is a cylinder made of transparent material, and the outer wall surface is marked with a height scale, so that crude oil and foam can be observed, and the existence time of foam in the foamed crude oil can be visually monitored and measured; the cylinder of the transparent reactor (14) The body wall thickness is 5mm, the inner diameter is 50mm, and the height is 500mm; the ratio of the height to the inner diameter is 10, which can reduce the volume measurement error caused by the uneven distribution of foam on the horizontal plane.

A transparent water jacket (15) is arranged on the outside of the transparent reaction kettle (14), and the transparent water jacket (15) is connected to the constant temperature water bath (16), and the circulating water circulates between the transparent water jacket (15) and the constant temperature water bath (16) Flow, keep transparent reactor (14) temperature constant.

The temperature sensor (17) is installed in the bottom cover of the transparent reactor (14), tests the temperature in the transparent reactor, and is connected with the control box (22), and the pressure sensor (18) is installed in the transparent reactor (14) The top cover is used to test the pressure in the transparent reactor, and is connected with the control box (22).

The motor (19) is installed on the top cover of the transparent reaction kettle (14) to drive the stirring shaft (20) to rotate. Stirring paddle (21) is installed on the stirring shaft (20), realizes stirring crude oil, promotes _CO gas dissolving. The motor (19) is connected with the control box (22), and its rotating speed is regulated by the control box (22).

The outlet back pressure valve (27) is combined with the seventh valve (23) and the eighth valve (25) to control the pressure drop rate in the transparent reactor; the outlet gas flowmeter (24) measures the gas volume flowing through the pipeline; The ninth valve (26) is a bypass valve.

Claims (2)

1. _CO in crude oil Solubility and foam stability testing device, it is characterized in that, comprise gas cylinder (1), on the outlet pipeline of gas cylinder (1), gas cylinder decompression valve (2) and first are installed successively Valve (3), the first valve (3) is respectively connected to the second valve (4) and the inlet pressure regulating valve (9) through a tee, and the other end of the second valve (4) is connected to the vacuum container (5) The top is connected, and the top of the vacuum container (5) is provided with a vacuum gauge (6) and a vacuum pump (7), and the bottom is also provided with a third valve (8); The other end of the inlet pressure regulating valve (9) is communicated with the transparent reactor (14) through the fourth valve (10), the inlet gas flowmeter (11), and the fifth valve (12) successively; 9) Between the transparent reaction kettle (14), there is also a bypass valve connected in parallel with the above-mentioned fourth valve (10), inlet gas flow meter (11), and the fifth valve (12)—the sixth valve ( 13); The transparent reaction kettle (14) comprises a transparent cylinder marked with a scale on the outer wall, a top cover and a bottom cover are respectively provided at the upper and lower ends of the cylinder, and a transparent water jacket (15) is arranged on the outside of the transparent reaction kettle (14). The water jacket (15) is connected to the constant temperature water bath (16), and the circulating water circulates between the transparent water jacket (15) and the constant temperature water bath (16) to keep the temperature of the transparent reactor (14) constant; Transparent reactor (14) bottom cover and top cover are provided with temperature sensor (17) and gas outlet (31) respectively, and wherein gas outlet (31) communicates with pressure sensor (18), and transparent reactor (14) top cover is also provided with Stirring motor (19) is arranged, and the stirring shaft (20) of this stirring motor (19) is positioned at transparent cylinder inside, and stirring shaft (20) is provided with stirring paddle (21); Described constant temperature water bath (16), temperature sensor (17), pressure sensor (18) and stirring motor (19) are connected with control box (22) respectively; The gas outlet (31) of the top cover of the transparent reaction kettle (14) is also connected to the outlet back pressure valve (27) through the seventh valve (23), the outlet gas flowmeter (24), and the eighth valve (25) successively, Between the gas outlet (31) of the transparent reactor (14) top cover and the outlet back pressure valve (27), it is also provided with the seventh valve (23), the outlet gas flow meter (24), the eighth valve ( 25) Bypass valves connected in parallel—the ninth valve (26). 2. CO in a kind of crude oil according to claim ₁ Solubility and foam stability testing device is characterized in that, described transparent reactor (14) bottom cover is also provided with emptying port (30).