Method and apparatus for testing adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil
By simulating the interfacial reaction between completion fluid and hydrogen sulfide-containing crude oil in a high-temperature and high-pressure reactor, and utilizing fugacity and gravity differentiation technologies, the problem of the inability to accurately assess the hydrogen sulfide resistance of completion fluid in existing technologies has been solved, and safe and reliable laboratory testing has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA NAT PETROLEUM CORP
- Filing Date
- 2022-09-30
- Publication Date
- 2026-06-23
AI Technical Summary
Existing technologies cannot accurately simulate the interfacial reaction between completion fluid and hydrogen sulfide-containing crude oil, and the experimental methods have safety hazards, making it impossible to truly assess the hydrogen sulfide resistance of completion fluid.
A high-temperature, high-pressure reactor was used to simulate the interfacial reaction between the completion fluid and the formation crude oil containing hydrogen sulfide. By controlling fugacity and gravity differentiation, the hydrogen sulfide was ensured to be in static contact with the completion fluid after being saturated in the crude oil. The suitability of the completion fluid was determined by combining density detection and ion content analysis.
This method enables a realistic simulation of the wellbore environment under laboratory conditions, accurately assesses the hydrogen sulfide resistance of completion fluids, reduces experimental risks, and provides a safe and reliable testing method.
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Figure CN117846542B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a testing method and equipment for the adaptability of water-based completion fluids in crude oil containing hydrogen sulfide, belonging to the field of petroleum engineering technology. Background Technology
[0002] Many oil reservoirs contain hydrogen sulfide in their crude oil, therefore, all working fluids used during well completion must be resistant to hydrogen sulfide. In particular, completion fluids, if reacting with hydrogen sulfide, can easily form precipitates that clog the wellbore or reservoir; more importantly, the density of the completion fluid may change, leading to well control risks. Therefore, completion fluids used in hydrogen sulfide-containing oil and gas wells need to undergo hydrogen sulfide resistance testing to ensure their stability in the hydrogen sulfide-containing wellbore environment.
[0003] However, the experimental design for the reaction of completion fluid with hydrogen sulfide-containing crude oil has always been a bottleneck problem in the industry. When completion fluid is stationary in the wellbore, it mainly serves to control the well. Its reaction with hydrogen sulfide-containing crude oil only occurs at the interface between the completion fluid and crude oil. Therefore, directly mixing completion fluid and crude oil for reaction is unreasonable. At the same time, hydrogen sulfide is a highly toxic gas, and mixing and reacting it can easily cause leakage, endangering the personal safety of experimental personnel.
[0004] Currently, the industry generally uses two methods to evaluate the hydrogen sulfide resistance of completion fluids: one is to prepare a dilute solution of hydrogen sulfide (i.e., hydrosulfuric acid) and mix it with the completion fluid to test its hydrogen sulfide resistance; the other is to place the completion fluid in a high-temperature, high-pressure reactor and then introduce hydrogen sulfide gas into the completion fluid to test its hydrogen sulfide resistance. Neither of these methods can simulate the actual interfacial reaction state, nor can they simulate the actual concentration of hydrogen sulfide. Testing the hydrogen sulfide resistance of completion fluids has always been one of the urgent problems to be solved in this field. Summary of the Invention
[0005] To address the aforementioned technical problems, the present invention aims to provide a testing method and equipment for the adaptability of water-based completion fluids in hydrogen sulfide-containing crude oil. The testing method provided by this invention can simulate the interfacial reaction between the completion fluid under well-killing conditions and the formation hydrogen sulfide-containing crude oil, accurately determining the adaptability of water-based completion fluids in hydrogen sulfide-containing crude oil.
[0006] To achieve the above objectives, the first aspect of the present invention provides a method for testing the adaptability of water-based completion fluids in crude oil containing hydrogen sulfide, comprising the following steps:
[0007] (1) Testing the completion fluid to be tested, the testing including at least testing the basic properties of the completion fluid to be tested, the basic properties testing including at least density testing;
[0008] (2) Pump crude oil into a high-temperature and high-pressure reactor, and then introduce hydrogen sulfide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide.
[0009] (3) Deoxygenate the well completion fluid to be tested, and then introduce the deoxygenated well completion fluid to be tested into the high temperature and high pressure reactor;
[0010] (4) Heat the high-temperature and high-pressure reactor to the set temperature and adjust its pressure to the set pressure, which is the fugacity of hydrogen sulfide, and then keep it stable; measure the temperature and pressure of the high-temperature and high-pressure reactor every once in a while. If the temperature and / or pressure are different from the set temperature and / or set pressure, adjust the temperature and / or pressure of the high-temperature and high-pressure reactor to make them the same as the set temperature and set pressure.
[0011] (5) After the set reaction time is reached, release the pressure, stop heating and allow the high-temperature and high-pressure reactor to cool to room temperature, and discharge the fluid inside;
[0012] (6) Test the reaction-treated completion fluid, the test including at least the test of the basic properties of the reaction-treated completion fluid, the test of the basic properties of the reaction-treated completion fluid including at least density test;
[0013] (7) Based at least on the test results of the completion fluid to be tested obtained in step (1) and the test results of the post-reaction completion fluid obtained in step (6), determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
[0014] According to a specific embodiment of the present invention, preferably, the testing method further includes preliminary screening after step (1), the preliminary screening including:
[0015] (a)-1 The crude oil is pumped into a high-temperature and high-pressure reactor, and then hydrogen sulfide gas is introduced into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide.
[0016] (a)-2 Deoxygenate the well completion fluid to be tested, and then introduce the deoxygenated well completion fluid to be tested into the high temperature and high pressure reactor;
[0017] (a)-3 Heat the high-temperature and high-pressure reactor to the set temperature and adjust its pressure to atmospheric pressure as the set pressure, and then keep it stable; measure the temperature of the high-temperature and high-pressure reactor every once in a while. If the temperature is different from the set temperature, adjust the temperature of the high-temperature and high-pressure reactor to be the same as the set temperature.
[0018] (a)-4 After the set reaction time is reached, stop heating and allow the high-temperature and high-pressure reactor to cool to room temperature, then discharge the fluid inside.
[0019] (a)-5 The reaction-treated completion fluid is tested, and the testing includes at least the testing of the basic properties of the reaction-treated completion fluid, which includes at least density testing.
[0020] (a)-6 Based at least on the test results of the completion fluid to be tested and the test results of the completion fluid after reaction, it is preliminarily determined whether the completion fluid is suitable for crude oil containing hydrogen sulfide. The completion fluid that is preliminarily determined to be suitable for crude oil containing hydrogen sulfide is then subjected to steps (2) to (7) to finally determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
[0021] Those skilled in the art should understand that since the basic performance test of the well completion fluid has been performed in step (1) above, it is not necessary to repeat the basic performance test of the well completion fluid during the preliminary screening process.
[0022] In the above method, preferably, in step (1), the basic performance testing of the well completion fluid to be tested also includes one or a combination of pH value testing, viscosity testing, crystallization temperature testing and turbidity testing.
[0023] In the above method, preferably, in step (1), the detection of the well completion fluid to be tested also includes detecting the ion content of the well completion fluid to be tested.
[0024] In the above method, preferably, in steps (2) and (a)-1, the amount of crude oil pumped into the high-temperature and high-pressure reactor is 1000-3000 mL.
[0025] In the above method, preferably, in steps (2) and (a)-1, the hydrogen sulfide gas is introduced for 1.5 to 2.5 hours to saturate the crude oil with hydrogen sulfide, that is, to dissolve as much hydrogen sulfide as possible in the crude oil, while minimizing the influence of other residual gases in the reactor.
[0026] In the above method, preferably, steps (2) and (a)-1 further include: introducing carbon dioxide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide and carbon dioxide. The time for introducing hydrogen sulfide gas and carbon dioxide gas can be 1.5 to 2.5 hours.
[0027] In the above method, in steps (3) and (a)-2, the deoxygenation of the completion fluid to be tested can be performed using conventional completion fluid deoxygenation methods in the art. Preferably, the deoxygenation method can be activated carbon deoxygenation. The specific operation method of activated carbon deoxygenation and the ratio of activated carbon to the completion fluid to be tested can be conventionally adjusted by those skilled in the art.
[0028] In the above method, preferably, in steps (3) and (a)-2, the amount of deoxygenated well completion fluid to be tested introduced into the high-temperature and high-pressure reactor is 1000-3000 mL.
[0029] In the above method, preferably, the amount of crude oil pumped into the high-temperature and high-pressure reactor is the same as the amount of deoxygenated well completion fluid to be tested introduced into the high-temperature and high-pressure reactor.
[0030] In the above method, preferably, in step (4), the fugacity of the hydrogen sulfide is calculated according to the following formula (1):
[0031]
[0032] In formula (1), The value represents the fugacity of hydrogen sulfide, expressed in MPa. This represents the partial pressure of hydrogen sulfide, expressed in MPa. This is the fugacity coefficient.
[0033] The partial pressure of hydrogen sulfide refers to the partial pressure of hydrogen sulfide in hydrogen sulfide-containing crude oil. Its calculation method is conventional in this field, generally obtained by multiplying the total system pressure (i.e., the formation pressure of the hydrogen sulfide-containing crude oil) by the mole fraction of hydrogen sulfide in the gas phase. Fugacity coefficient. Alternatively, calculations can be performed using conventional methods in this field. For example, the fugacity coefficients of components in a mixture can be calculated using the formula disclosed on pages 6-8 of "Improvement of the SRK Equation and Its Application in Phase Equilibrium Calculations" (Luo Mingjian, Master's Thesis, Tianjin University, December 2005), which combines the SRK equation with the 1-parameter van der Waals mixing rule, i.e., Equation (2-34).
[0034] In the above method, preferably, in steps (4) and (a)-3, the set temperature is the crude oil temperature of the working formation of the well completion fluid to be tested, and more preferably it can be 80-120℃.
[0035] In the above method, preferably, in step (4), the temperature and pressure of the high-temperature and high-pressure reactor are measured every 60 to 80 hours.
[0036] In the above method, preferably, in step (a)-3, the temperature of the high-temperature and high-pressure reactor is measured every 24 to 80 hours. More preferably, the temperature of the high-temperature and high-pressure reactor is measured every 60 to 80 hours.
[0037] In the above method, preferably, in step (4), the temperature of the high-temperature and high-pressure reactor is adjusted by the heating intensity, and the pressure of the high-temperature and high-pressure reactor is adjusted by introducing hydrogen sulfide gas. More preferably, when the measured pressure of the high-temperature and high-pressure reactor is more than 0.5 MPa lower than the set pressure, hydrogen sulfide gas is introduced into the high-temperature and high-pressure reactor to replenish the pressure to the set pressure. More preferably, when adjusting the pressure, the flow rate of hydrogen sulfide gas is less than 10 mm / min, and the flow rate is 150 to 250 mL / min (especially preferably 200 mL / min). Alternatively, if step (2) further includes: introducing carbon dioxide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide and carbon dioxide, the pressure of the high-temperature and high-pressure reactor can be adjusted by introducing hydrogen sulfide gas and carbon dioxide gas. Preferably, the flow rate of both hydrogen sulfide gas and carbon dioxide gas is less than 10 mm / min, and the flow rate is 150 to 250 mL / min (more preferably 200 mL / min). During pressurization, the gas flow rate and flow rate specified in this application can be used to avoid disturbances and flow impacts at the gas outlet in the reactor, thereby preventing convection at the interface between crude oil and completion fluid.
[0038] In the above method, preferably, in step (a)-3, the temperature of the high-temperature and high-pressure reactor is adjusted by the intensity of heating.
[0039] In the above method, preferably, in step (5), the set reaction time is 6-8 days.
[0040] In the above method, preferably, in steps (a)-4, the set reaction time is 1 day to 2 months. More preferably, the set reaction time is 1 month to 2 months.
[0041] In the above method, preferably, in steps (6) and (a)-5, the basic performance testing of the completed fluid after the reaction also includes one or a combination of pH value testing, viscosity testing, crystallization temperature testing and turbidity testing.
[0042] In the above method, preferably, the detection of the reaction-treated completion fluid in steps (6) and (a)-5 further includes detecting the ion content of the reaction-treated completion fluid.
[0043] In the above method, preferably, in step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide includes the following method: if the density change of the completion fluid before and after the reaction is greater than 0.2SG or there is obvious precipitation in the completion fluid after the reaction, then the completion fluid is not suitable for crude oil containing hydrogen sulfide. More preferably, the obvious precipitation is defined as a precipitation amount of 100g / 1000mL (amount of completion fluid after reaction) or more after passing through a 300-400 mesh (more preferably 400 mesh) filter. Herein, SG (specific gravity) is the ratio of the density of the completion fluid to the density of water under standard atmospheric pressure and 3.98℃.
[0044] In the above method, preferably, in step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following methods: if the pH value of the completion fluid to be tested is above 2, or if the viscosity change of the completion fluid before and after the reaction is above 10 mPa·s, or if the crystallization temperature change of the completion fluid before and after the reaction is above 5°C, or if the turbidity change of the completion fluid before and after the reaction is above 10 NTU, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
[0045] In the above method, preferably, in step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following method: if the change in the content of the main ions in the completion fluid before and after the reaction is greater than 0.05 kg / L, then the completion fluid is not suitable for crude oil containing hydrogen sulfide. The main ions include calcium ions, zinc ions, etc., which mainly originate from inorganic salts commonly used in the completion fluid.
[0046] In the above method, in step (7), if the density change of the completion fluid before and after the reaction is less than 0.2SG and there is no obvious precipitation in the completion fluid after the reaction, and if the pH value, viscosity, crystallization temperature, turbidity and ion content of the completion fluid before and after the reaction are also tested, then all of them must not meet the above-mentioned index conditions that are not suitable for completion fluids containing hydrogen sulfide crude oil, then the completion fluid is suitable for completion fluids containing hydrogen sulfide crude oil.
[0047] In the above method, preferably, in step (a)-6, the preliminary determination of whether the completion fluid is suitable for hydrogen sulfide-containing crude oil includes the following methods: if the density change of the completion fluid before and after the reaction is greater than 0.2SG or there is obvious precipitation in the completion fluid after the reaction, then the completion fluid is not suitable for hydrogen sulfide-containing crude oil; if the density change of the completion fluid before and after the reaction is less than 0.2SG and there is no obvious precipitation in the completion fluid after the reaction, then the completion fluid is preliminarily determined to be suitable for hydrogen sulfide-containing crude oil. More preferably, the obvious precipitation is defined as the amount of precipitation after passing through a 300-400 mesh (more preferably 400 mesh) filter screen being 100g / 1000mL (amount of completion fluid after the reaction) or more. The completion fluids that are preliminarily screened as suitable for hydrogen sulfide-containing crude oil are subjected to the above steps (2) to (7) to finally determine whether the completion fluid is suitable for hydrogen sulfide-containing crude oil.
[0048] In the above method, preferably, in step (a)-6, the preliminary determination of whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following methods: if the pH value of the completion fluid to be tested is above 2, or if the viscosity change of the completion fluid before and after the reaction is above 10 mPa·s, or if the crystallization temperature change of the completion fluid before and after the reaction is above 5°C, or if the turbidity change of the completion fluid before and after the reaction is above 10 NTU, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
[0049] In the above method, preferably, in step (a)-6, the preliminary determination of whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following: if the change in the main ion content of the completion fluid before and after the reaction is greater than 0.05 kg / L, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
[0050] In the above method, in step (a)-6, during the preliminary screening process, if the pH value, viscosity, crystallization temperature, turbidity, and ion content of the completion fluid before and after the reaction are also tested, then all of them must not meet the above-mentioned index conditions for completion fluids that are not suitable for crude oil containing hydrogen sulfide. Therefore, it is preliminarily determined that the completion fluid is suitable for crude oil containing hydrogen sulfide.
[0051] In the above method, preferably, step (a)-6 further includes: steps (2) to (7) can also be performed for completion fluids that are initially determined to be unsuitable for crude oil containing hydrogen sulfide, so as to finally determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
[0052] The present invention provides a method for testing the adaptability of water-based completion fluids in hydrogen sulfide-containing crude oil. This method is used for testing the hydrogen sulfide resistance of water-based completion fluids in oil and gas wells. It can simulate the interfacial reaction between the completion fluid and the formation hydrogen sulfide-containing crude oil when the completion fluid is in a well-killing state, and accurately determine the adaptability of the water-based completion fluid in hydrogen sulfide-containing crude oil. This method has at least the following groundbreaking advancements:
[0053] (1) This invention uses the fugacity of hydrogen sulfide in crude oil under specific temperature and pressure conditions to simulate experimental pressure conditions. On the one hand, it is more realistic and effective (fugacity represents the effective pressure of a real gas in chemical thermodynamics); on the other hand, it has a lower value than partial pressure, making it easier to achieve in the laboratory than using partial pressure to simulate experimental pressure, and the experimental risk is smaller.
[0054] In the petroleum industry, experiments involving hydrogen sulfide assume it to be in a gaseous state, and the pressure of hydrogen sulfide is obtained by multiplying the total system pressure by the mole fraction of hydrogen sulfide in the gas phase. The industry standard NACE TM0177: Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking and Stress Corrosion Cracking in H2S Environments, also recommends using the partial pressure of hydrogen sulfide in the gas to simulate a corrosive environment containing hydrogen sulfide—mixing hydrogen sulfide with nitrogen or carbon dioxide to achieve the required partial pressure, and then passing the mixed gas into the reaction solution.
[0055] In the reaction of hydrogen sulfide in its dissolved state with the completion fluid, as described in this invention, the above-mentioned simulation experiment using partial pressure is unreasonable because the chemical reactivity of hydrogen sulfide is much lower in this state than in its gaseous state. If partial pressure is used for characterization, the reactivity of hydrogen sulfide is estimated to be too high (especially under high temperature and high pressure conditions), which does not conform to reality; and if the pressure of the reaction environment is too high, it is difficult to simulate under laboratory conditions. Therefore, this invention creatively uses fugacity to characterize the chemical reactivity of hydrogen sulfide in its dissolved state.
[0056] (2) This invention utilizes the density difference and gravitational differentiation between water-based completion fluid and crude oil to simulate the interfacial reaction between completion fluid and hydrogen sulfide-containing crude oil. Crude oil is first placed in the reactor, and then hydrogen sulfide is introduced until saturation. After that, deoxygenated completion fluid is pumped into the reactor. Because the completion fluid has a high density, it will accumulate below the hydrogen sulfide-containing crude oil, thus ensuring that during the reaction process, hydrogen sulfide only reacts with the completion fluid through mass transfer to the crude oil interface.
[0057] In the petroleum industry, the reaction between hydrogen sulfide and well fluid is often tested by directly introducing hydrogen sulfide gas into the liquid phase. However, this method is far from simulating the contact reaction between hydrogen sulfide-containing crude oil and well fluid. When using this method to conduct the experiments of this invention, the measured reaction rate will inevitably be much higher than the actual reaction rate. This is because the reaction rate between crude oil containing dissolved hydrogen sulfide and completion fluid depends on two processes: convection and mass transfer. Therefore, simulating the mass transfer-controlled reaction process is crucial. In the application scenario of this invention, both the completion fluid and crude oil are static, and the hydrogen sulfide is also in a dissolved, static liquid phase with no convection. The only factor affecting the reaction rate is mass transfer. This invention first saturates the crude oil with hydrogen sulfide, and then allows it to contact and react with the completion fluid in a static state, completely and realistically simulating the working state of the completion fluid. This is an innovative advancement in the industry.
[0058] Furthermore, the order in which the fluids are introduced is crucial in this invention. If the completion fluid is introduced first, followed by the crude oil, it is impossible to saturate the crude oil with hydrogen sulfide, and it cannot be guaranteed that the completion fluid and hydrogen sulfide will not undergo a convective reaction. The method of this invention, however, involves first introducing crude oil and then saturating it with hydrogen sulfide, followed by the completion fluid; maintaining a static state throughout the entire reaction process, it realistically simulates the mass transfer reaction at the interface.
[0059] (3) This invention ensures constant experimental pressure conditions throughout the reaction process by pressurizing. During the experimental reaction, if the system pressure drop is detected to be greater than 0.5 MPa, hydrogen sulfide gas is introduced to replenish the pressure, ensuring that the pressure value throughout the reaction process is equal to the set fugacity value.
[0060] A second aspect of the present invention provides a testing device for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil. The device is used to implement the aforementioned testing method for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil. The device includes at least: a high-temperature, high-pressure reactor, a hydrogen sulfide tank, a completion fluid inlet pipeline, a gas outlet pipeline, a pressure measuring device, and a temperature control device. The temperature control device includes a heating unit, a temperature measuring unit, and a regulating unit.
[0061] The hydrogen sulfide tank is connected to the high-temperature and high-pressure reactor via a pipeline; the completion fluid inlet pipeline is connected to the high-temperature and high-pressure reactor; the gas outlet pipeline is connected to the high-temperature and high-pressure reactor; the pressure measuring device is installed on the gas outlet pipeline via a tee; the heating unit is located inside the high-temperature and high-pressure reactor; the temperature measuring unit is connected to the high-temperature and high-pressure reactor; and the regulating unit collects the temperature measured by the temperature measuring unit and controls the heating intensity of the heating unit to adjust the temperature of the high-temperature and high-pressure reactor.
[0062] In the above-mentioned equipment, preferably, the opening of the hydrogen sulfide tank is provided with a pressure regulator.
[0063] In the aforementioned equipment, preferably, a pressure-replenishing valve is provided at the inlet of the hydrogen sulfide tank, and the pressure-replenishing valve controls the needle valve and the check valve. The pressure-replenishing valve is located closer to the inlet of the hydrogen sulfide tank than the needle valve. More preferably, the nominal diameter of the needle valve is 5 mm. The pressure-replenishing valve used in this invention includes a needle valve capable of precise flow control and a check valve to prevent backflow. If a system pressure drop greater than 0.5 MPa is detected, the check valve and the needle valve are opened for pressure replenishment, but the opening degree of the needle valve should be low to ensure a low flow rate of the replenished hydrogen sulfide gas, so as to avoid disturbance and flow impact at the outlet of the hydrogen sulfide gas in the reactor, thereby avoiding convection at the interface of crude oil and completion fluid. Therefore, this invention preferably uses a needle valve with a nominal diameter of 5 mm.
[0064] According to a specific embodiment of the present invention, preferably, the testing equipment for the adaptability of the water-based completion fluid in crude oil containing hydrogen sulfide further includes a carbon dioxide tank, wherein the carbon dioxide tank is connected to the pipeline connecting the hydrogen sulfide tank and the high-temperature and high-pressure reactor via a tee.
[0065] In the above-mentioned equipment, preferably, the carbon dioxide tank and the tank opening are provided with a pressure regulator.
[0066] In the above-described equipment, preferably, the carbon dioxide tank is equipped with a one-way valve at its opening, and a needle valve is provided on the pipeline connecting the tee to the high-temperature and high-pressure reactor. More preferably, the nominal diameter of the needle valve is 5 mm.
[0067] According to a specific embodiment of the present invention, preferably, the testing equipment for the adaptability of the water-based completion fluid in hydrogen sulfide-containing crude oil further includes a hydrogen sulfide absorption device, wherein one end of the gas discharge pipeline is connected to the high-temperature and high-pressure reactor, and the other end is connected to the hydrogen sulfide absorption device. More preferably, the hydrogen sulfide absorption device contains a sodium hydroxide solution.
[0068] According to a specific embodiment of the present invention, preferably, the testing equipment for the adaptability of the water-based completion fluid in crude oil containing hydrogen sulfide further includes a completion fluid storage device, wherein one end of the completion fluid inlet pipeline is connected to the high-temperature and high-pressure reactor, and the other end is connected to the completion fluid storage device.
[0069] This invention provides a testing method and equipment for the adaptability of water-based completion fluids in hydrogen sulfide-containing crude oil. It can simulate the interfacial reaction between the completion fluid and the formation hydrogen sulfide-containing crude oil when the completion fluid is under well-killing conditions. The experimental pressure is represented by the fugacity of hydrogen sulfide in the crude oil, and the reaction at the interface between the completion fluid and crude oil is simulated using the principle of gravity differentiation through the design of the hydrogen sulfide gas introduction method. This more accurately simulates the actual reaction state of the formation. The test results can provide a basis for whether the completion fluid can be used in a hydrogen sulfide-containing crude oil environment, thus providing experimental evidence for the optimal selection of completion fluids for high-pressure sulfur-containing oil and gas wells. Attached Figure Description
[0070] Figure 1 A schematic diagram of the structure of the testing equipment for the adaptability of the water-based completion fluid in hydrogen sulfide-containing crude oil provided in Example 1;
[0071] Figure 2 This is a schematic diagram of the structure of the testing equipment for the adaptability of the water-based completion fluid in hydrogen sulfide-containing crude oil provided in Example 2;
[0072] Explanation of main component symbols: 1. High temperature and high pressure reactor; 2. Hydrogen sulfide tank; 3. Completion fluid inlet pipeline; 4. Completion fluid storage device; 5. Gas outlet pipeline; 6. Pressure measuring device; 7. Hydrogen sulfide absorption device; 8. Heating unit; 9. Temperature measuring unit; 10. Adjustment unit; 11. Pressure reducing regulator; 12. Needle valve; 13. Check valve; 14. Carbon dioxide tank; 15. First tee; 16. Second tee. Detailed Implementation
[0073] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.
[0074] Example 1
[0075] This embodiment provides a testing device for the adaptability of water-based completion fluids in crude oil containing hydrogen sulfide, such as... Figure 1 As shown, the equipment includes: a high-temperature and high-pressure reactor 1, a hydrogen sulfide tank 2, a completion fluid inlet pipeline 3, a completion fluid storage device 4, a gas outlet pipeline 5, a pressure measuring device 6, a temperature control device, and a hydrogen sulfide absorption device 7; the temperature control device includes a heating unit 8, a temperature measuring unit 9, and an adjustment unit 10.
[0076] The hydrogen sulfide tank 2 is connected to the high-temperature and high-pressure reactor 1 via a pipeline; one end of the completion fluid inlet pipeline 3 is connected to the high-temperature and high-pressure reactor 1, and the other end is connected to the completion fluid storage device 4; one end of the gas outlet pipeline 5 is connected to the high-temperature and high-pressure reactor 1, and the other end is connected to the hydrogen sulfide absorption device 7, which contains a sodium hydroxide solution; the pressure measuring device 6 is installed on the gas outlet pipeline 5 via a first tee 15; the heating unit 8 is installed inside the high-temperature and high-pressure reactor 1; the temperature measuring unit 9 is connected to the high-temperature and high-pressure reactor; the regulating unit 10 collects the temperature measured by the temperature measuring unit 9 and controls the heating intensity of the heating unit 8 to adjust the temperature of the high-temperature and high-pressure reactor 1;
[0077] The hydrogen sulfide tank 2 is equipped with a pressure regulator 11 at its opening;
[0078] The hydrogen sulfide tank 2 is also equipped with a pressure relief valve at its opening. The pressure relief valve includes a needle valve 12 and a one-way valve 13. The nominal diameter of the needle valve is 5 mm.
[0079] In this embodiment, the high-temperature and high-pressure reactor is model FCZ3-31 / 325C276, and the other devices and units are conventional devices and units in the art.
[0080] Example 2
[0081] This embodiment provides a testing device for the adaptability of water-based completion fluids in crude oil containing hydrogen sulfide, such as... Figure 2 As shown, the equipment includes: a high-temperature and high-pressure reactor 1, a hydrogen sulfide tank 2, a carbon dioxide tank 14, a completion fluid inlet pipeline 3, a completion fluid storage device 4, a gas outlet pipeline 5, a pressure measuring device 6, a temperature control device, and a hydrogen sulfide absorption device 7; the temperature control device includes a heating unit 8, a temperature measuring unit 9, and an adjustment unit 10.
[0082] The hydrogen sulfide tank 2 is connected to the high-temperature and high-pressure reactor 1 via a pipeline; the carbon dioxide tank 14 is connected to the pipeline connecting the hydrogen sulfide tank 2 and the high-temperature and high-pressure reactor 1 via a second tee 16; one end of the completion fluid inlet pipeline 3 is connected to the high-temperature and high-pressure reactor 1, and the other end is connected to the completion fluid storage device 4; one end of the gas outlet pipeline 5 is connected to the high-temperature and high-pressure reactor 1, and the other end is connected to the hydrogen sulfide absorption device 7, which contains sodium hydroxide solution; the pressure measuring device 6 is installed on the gas outlet pipeline 5 via a first tee 15; the heating unit 8 is installed inside the high-temperature and high-pressure reactor 1; the temperature measuring unit 9 is connected to the high-temperature and high-pressure reactor; the regulating unit 10 collects the temperature measured by the temperature measuring unit 9 and controls the heating intensity of the heating unit 8 to adjust the temperature of the high-temperature and high-pressure reactor 1;
[0083] The hydrogen sulfide tank 2 is equipped with a pressure reducing regulator 11 at its opening, and a one-way valve 13 is also provided at its opening.
[0084] The carbon dioxide tank 14 is equipped with a pressure regulator 11 at its opening, and a one-way valve 13 is also provided at its opening.
[0085] A needle valve 12 is installed on the pipeline connecting the second three-way valve 16 to the high-temperature and high-pressure reactor 1. The nominal diameter of the needle valve 12 is 5 mm.
[0086] In this embodiment, the high-temperature and high-pressure reactor is model FCZ3-31 / 325C276, and the other devices and units are conventional devices and units in the art.
[0087] Example 3
[0088] This embodiment provides a test method for the adaptability of water-based completion fluid in crude oil containing hydrogen sulfide. The test equipment provided in Embodiment 1 is used to test the adaptability of CaBr2 / ZnCl2 completion fluid in crude oil containing hydrogen sulfide.
[0089] The method includes the following steps:
[0090] (1) The basic properties and main ion content of the well completion fluid (i.e., CaBr2 / ZnCl2 well completion fluid) were tested at 24℃, -28℃ and 100℃ respectively. The basic properties included density, turbidity, pH value, viscosity and crystallization temperature. The density tester (model SY-1 / 3), pH tester (model STARTER 300) and turbidity tester (model 1900C) used were all conventional in this field. The results are shown in Tables 1 to 4.
[0091] Table 1. Results of basic performance tests of CaBr2 / ZnCl2 completion fluid at different temperatures.
[0092]
[0093] Initial screening:
[0094] (a)-1 Pump 1000 mL of crude oil into a high-temperature and high-pressure reactor, and then introduce hydrogen sulfide gas into the high-temperature and high-pressure reactor for 2 hours until the crude oil is saturated with hydrogen sulfide.
[0095] (a)-2 The well completion fluid to be tested was deoxygenated by activated carbon, and then 1000 mL of the deoxygenated well completion fluid to be tested was introduced into the high temperature and high pressure reactor.
[0096] (a)-3 Heat the high-temperature and high-pressure reactor to a set temperature of 100°C, and adjust its pressure to atmospheric pressure as the set pressure, and then keep it stable; measure the temperature of the high-temperature and high-pressure reactor every 3 days, and if the temperature is different from the set temperature, adjust the temperature of the high-temperature and high-pressure reactor to be the same as the set temperature; wherein, the temperature of the high-temperature and high-pressure reactor is adjusted by the intensity of heating;
[0097] (a)-4 After the set reaction time is reached, heating is stopped, and the high-temperature and high-pressure reactor is cooled to room temperature and the fluid inside is discharged; wherein the set reaction time is 1 day, 3 days, 7 days, 15 days and 30 days respectively;
[0098] (a)-5 The basic properties and main ion content of the well completion fluid after reaction were tested at 1 day, 3 days, 7 days, 15 days and 30 days, respectively, under normal temperature and pressure. The basic properties of the well completion fluid after reaction were tested at least including density test and pH value test. The results are shown in Table 3 and Table 4.
[0099] (a)-6 Preliminary judgment on whether the completion fluid is suitable for crude oil containing hydrogen sulfide: As can be seen from the data in Tables 3 and 4, the pH value of the completion fluid to be tested is less than 2, the density change of the completion fluid before and after the reaction is less than 0.2SG, the amount of sediment in the completion fluid after the reaction after passing through a 400-mesh filter is more than 100g / 1000mL, there is obvious sedimentation, and the results of repeated experiments are consistent (i.e., the experimental results of 1 day, 3 days, 7 days, 15 days, and 30 days are consistent), and the change in zinc ion content of the completion fluid before and after the reaction is more than 0.05kg / L in some repeated experiments. Therefore, it is preliminarily judged that the completion fluid is not suitable for crude oil containing hydrogen sulfide.
[0100] However, the completion fluid will still be subjected to the following steps (2) to (8) to finally determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide;
[0101] (2) Calculate the fugacity of hydrogen sulfide according to the following formula (1), and use the calculated fugacity of hydrogen sulfide as the experimental set pressure.
[0102]
[0103] In formula (1), The value represents the fugacity of hydrogen sulfide, expressed in MPa. This represents the partial pressure of hydrogen sulfide, expressed in MPa. The fugacity coefficient;
[0104] The partial pressure of hydrogen sulfide refers to the partial pressure of hydrogen sulfide in hydrogen sulfide-containing crude oil. Its calculation method is conventional in this field, generally obtained by multiplying the total system pressure (i.e., the formation pressure of the hydrogen sulfide-containing crude oil) by the mole fraction of hydrogen sulfide in the gas phase; the fugacity coefficient... The fugacity coefficient of the components in the mixture is calculated according to the formula for calculating the fugacity coefficient of the components obtained by combining the SRK equation with the 1-parameter van der Waals mixing rule, as disclosed on pages 6-8 of "Improvement of SRK Equation and Its Application in Phase Equilibrium Calculation" (Luo Mingjian, Master's Thesis of Tianjin University, December 2005), i.e., Equation (2-34); the fugacity of hydrogen sulfide is calculated to be 5.8 MPa.
[0105] (3) Pump 1000 mL of crude oil into a high-temperature and high-pressure reactor, and then introduce hydrogen sulfide gas into the high-temperature and high-pressure reactor for 2 hours until the crude oil is saturated with hydrogen sulfide.
[0106] (4) Use activated carbon to deoxygenate the well completion fluid to be tested, and then introduce 1000 mL of the deoxygenated well completion fluid to be tested into the high temperature and high pressure reactor.
[0107] (5) Heat the high-temperature and high-pressure reactor to the set temperature, which is 100°C, and adjust its pressure to the set pressure obtained in step (2), i.e., 5.8 MPa, and then keep it stable; measure the temperature and pressure of the high-temperature and high-pressure reactor every 3 days. If the temperature and / or pressure are different from the set temperature and / or set pressure, adjust the temperature and / or pressure of the high-temperature and high-pressure reactor to make them the same as the set temperature and set pressure.
[0108] The temperature of the high-temperature and high-pressure reactor is adjusted by the heating intensity, and the pressure of the high-temperature and high-pressure reactor is adjusted by introducing hydrogen sulfide gas. When the measured pressure of the high-temperature and high-pressure reactor is more than 0.5 MPa lower than the set pressure, hydrogen sulfide gas is introduced into the high-temperature and high-pressure reactor to replenish the pressure to the set pressure. When adjusting the pressure, the flow rate of hydrogen sulfide gas is less than 10 mm / min and the flow rate is 200 mL / min.
[0109] (6) After the set reaction time is reached, release the pressure, stop heating and allow the high-temperature and high-pressure reactor to cool to room temperature, and discharge the fluid therein; wherein, the set reaction time is 7 days;
[0110] (7) The basic properties and main ion content of the well completion fluid after reaction were tested at room temperature and pressure. The basic properties of the well completion fluid after reaction were tested at least including density test and pH value test. The results are shown in Table 2, Table 3 and Table 4.
[0111] Table 2. Detection results of basic properties and main ion content of completion fluid before and after reaction at ambient temperature and pressure.
[0112]
[0113] Table 3. Test results of the basic properties of CaBr2 / ZnCl2 completion fluid before and after reaction under normal temperature and pressure.
[0114]
[0115] Table 4. Results of the main ion content of CaBr2 / ZnCl2 completion fluid before and after reaction at ambient temperature and pressure.
[0116]
[0117] (8) The results are: the pH value of the completion fluid to be tested is less than 2, and the density change of the completion fluid before and after the reaction is less than 0.2SG. However, the amount of sediment in the completion fluid after the reaction is more than 100g / 1000mL after passing through a 400-mesh filter, indicating obvious sedimentation. Therefore, the completion fluid is not suitable for crude oil containing hydrogen sulfide.
Claims
1. A method for testing the adaptability of water-based completion fluid in crude oil containing hydrogen sulfide, comprising the following steps: (1) Testing the completion fluid to be tested, wherein the testing includes at least testing the basic properties of the completion fluid to be tested, and the basic properties testing of the completion fluid to be tested includes at least density testing; (2) Pump crude oil into a high-temperature and high-pressure reactor, and then introduce hydrogen sulfide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide; (3) Deoxygenate the well completion fluid to be tested, and then introduce the deoxygenated well completion fluid to be tested into the high temperature and high pressure reactor; (4) Heat the high-temperature and high-pressure reactor to the set temperature and adjust its pressure to the set pressure, which is the fugacity of hydrogen sulfide, and then keep it stable. Measure the temperature and pressure of the high-temperature and high-pressure reactor at regular intervals. If the temperature and / or pressure are different from the set temperature and / or set pressure, adjust the temperature and / or pressure of the high-temperature and high-pressure reactor to make them the same as the set temperature and set pressure. (5) After the set reaction time is reached, release the pressure, stop heating and allow the high-temperature and high-pressure reactor to cool to room temperature, and discharge the fluid inside; (6) Test the reaction-treated completion fluid, the test including at least the test of the basic properties of the reaction-treated completion fluid, the test of the basic properties of the reaction-treated completion fluid including at least the density test; (7) Based at least on the test results of the completion fluid to be tested obtained in step (1) and the test results of the post-reaction completion fluid obtained in step (6), determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
2. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, The testing method further includes preliminary screening after step (1), which includes: (a)-1 The crude oil is pumped into a high-temperature and high-pressure reactor, and then hydrogen sulfide gas is introduced into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide; (a) -2 Deoxygenate the well completion fluid to be tested, and then introduce the deoxygenated well completion fluid to be tested into the high temperature and high pressure reactor; (a) -3 Heat the high-temperature and high-pressure reactor to the set temperature and adjust its pressure to atmospheric pressure as the set pressure, and then keep it stable; measure the temperature of the high-temperature and high-pressure reactor every once in a while. If the temperature is different from the set temperature, adjust the temperature of the high-temperature and high-pressure reactor to be the same as the set temperature. (a) -4 After the set reaction time is reached, stop heating and allow the high-temperature and high-pressure reactor to cool to room temperature, then discharge the fluid inside; (a)-5 The reaction-treated completion fluid is tested, and the testing includes at least the testing of the basic properties of the reaction-treated completion fluid, and the testing of the basic properties of the reaction-treated completion fluid includes at least density testing; (a)-6 Based at least on the test results of the completion fluid to be tested and the test results of the completion fluid after reaction, it is preliminarily determined whether the completion fluid is suitable for crude oil containing hydrogen sulfide. The completion fluid that is preliminarily determined to be suitable for crude oil containing hydrogen sulfide is then subjected to steps (2) to (7) to finally determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
3. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, Step (a)-6 also includes: for completion fluids that are initially determined to be unsuitable for crude oil containing hydrogen sulfide, steps (2) to (7) are also performed to finally determine whether the completion fluid is suitable for crude oil containing hydrogen sulfide.
4. The test method for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (1), the basic performance testing of the well completion fluid to be tested also includes one or a combination of pH value testing, viscosity testing, crystallization temperature testing and turbidity testing.
5. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (1), the testing of the well completion fluid to be tested also includes testing the ion content of the well completion fluid to be tested.
6. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (2), the amount of crude oil pumped into the high-temperature and high-pressure reactor is 1000~3000mL.
7. The test method for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-1, the amount of crude oil pumped into the high-temperature and high-pressure reactor is 1000~3000mL.
8. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (2), the hydrogen sulfide gas is introduced for 1.5 to 2.5 hours.
9. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-1, the hydrogen sulfide gas is introduced for 1.5 to 2.5 hours.
10. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, Step (2) also includes: introducing carbon dioxide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide and carbon dioxide.
11. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, Step (a)-1 also includes: introducing carbon dioxide gas into the high-temperature and high-pressure reactor for a period of time until the crude oil is saturated with hydrogen sulfide and carbon dioxide.
12. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (3), the amount of deoxygenated well completion fluid to be tested introduced into the high-temperature and high-pressure reactor is 1000~3000mL.
13. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-2, the amount of deoxygenated well completion fluid to be tested introduced into the high-temperature and high-pressure reactor is 1000~3000mL.
14. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (4), the set temperature is the crude oil temperature of the working formation of the well completion fluid to be tested.
15. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 14, wherein, In step (4), the set temperature is 80~120℃.
16. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-3, the set temperature is the crude oil temperature of the working formation of the completion fluid to be tested.
17. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 16, wherein, In step (a)-3, the set temperature is 80~120℃.
18. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (4), the temperature and pressure of the high-temperature and high-pressure reactor are measured every 60 to 80 hours.
19. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-3, the temperature of the high-temperature and high-pressure reactor is measured every 24 to 80 hours.
20. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (4), the temperature of the high-temperature and high-pressure reactor is adjusted by the intensity of heating, and the pressure of the high-temperature and high-pressure reactor is adjusted by introducing hydrogen sulfide gas.
21. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 20, wherein, In step (4), when the measured pressure of the high-temperature and high-pressure reactor is more than 0.5 MPa lower than the set pressure, hydrogen sulfide gas is introduced into the high-temperature and high-pressure reactor to replenish the pressure to the set pressure.
22. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 20, wherein, In step (4), when adjusting the pressure, the flow rate of hydrogen sulfide gas is below 10 mm / min and the flow rate is 150~250 mL / min.
23. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-3, the temperature of the high-temperature and high-pressure reactor is adjusted by the intensity of heating.
24. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (5), the set reaction time is 6-8 days.
25. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In step (a)-4, the set reaction time is 1 day to 2 months.
26. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (6), the basic performance testing of the completed fluid after the reaction also includes one or a combination of pH value testing, viscosity testing, crystallization temperature testing, and turbidity testing.
27. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In steps (a)-5, the basic performance testing of the completed fluid after the reaction also includes one or a combination of pH value testing, viscosity testing, crystallization temperature testing, and turbidity testing.
28. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (6), the detection of the reacted completion fluid also includes detecting the ion content of the reacted completion fluid.
29. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In steps (a)-5, the testing of the reacted completion fluid also includes testing the ion content of the reacted completion fluid.
30. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 1, wherein, In step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide includes the following methods: if the density change of the completion fluid before and after the reaction is greater than 0.2SG or there is obvious precipitation in the completion fluid after the reaction, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
31. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 30, wherein, In step (7), the obvious precipitate is defined as the amount of precipitate after passing through a 300-400 mesh filter being 100g / 1000mL or more.
32. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 30, wherein, In step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following methods: if the pH value of the completion fluid to be tested is above 2, or if the viscosity change of the completion fluid before and after the reaction is above 10 mPa·s, or if the crystallization temperature change of the completion fluid before and after the reaction is above 5°C, or if the turbidity change of the completion fluid before and after the reaction is above 10 NTU, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
33. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 30, wherein, In step (7), determining whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following method: if the change in the main ion content of the completion fluid before and after the reaction is greater than 0.05 kg / L, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
34. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 2, wherein, In steps (a)-6, the preliminary determination of whether the completion fluid is suitable for crude oil containing hydrogen sulfide includes the following methods: if the density change of the completion fluid before and after the reaction is greater than 0.2SG or there is obvious precipitation in the completion fluid after the reaction, then the completion fluid is not suitable for crude oil containing hydrogen sulfide; if the density change of the completion fluid before and after the reaction is less than 0.2SG and there is no obvious precipitation in the completion fluid after the reaction, then it is preliminarily determined that the completion fluid is suitable for crude oil containing hydrogen sulfide.
35. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 34, wherein, In steps (a)-6, the obvious precipitate is defined as a precipitate of more than 100g / 1000mL after passing through a 300-400 mesh filter.
36. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 34, wherein, In step (a)-6, the preliminary determination of whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following methods: if the pH value of the completion fluid to be tested is above 2, or if the viscosity change of the completion fluid before and after the reaction is above 10 mPa·s, or if the crystallization temperature change of the completion fluid before and after the reaction is above 5°C, or if the turbidity change of the completion fluid before and after the reaction is above 10, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
37. The method for testing the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 34, wherein, In step (a)-6, the preliminary determination of whether the completion fluid is suitable for crude oil containing hydrogen sulfide further includes the following: if the change in the main ion content of the completion fluid before and after the reaction is greater than 0.05 kg / L, then the completion fluid is not suitable for crude oil containing hydrogen sulfide.
38. A testing apparatus for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil, the apparatus being used to implement the testing method for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to any one of claims 1-37, the apparatus comprising at least: The system includes a high-temperature and high-pressure reactor, a hydrogen sulfide tank, a completion fluid inlet pipeline, a gas outlet pipeline, a pressure measuring device, and a temperature control device; the temperature control device includes a heating unit, a temperature measuring unit, and a regulating unit. The hydrogen sulfide tank is connected to the high-temperature and high-pressure reactor via a pipeline; the completion fluid inlet pipeline is connected to the high-temperature and high-pressure reactor; the gas outlet pipeline is connected to the high-temperature and high-pressure reactor; the pressure measuring device is installed on the gas outlet pipeline via a tee; the heating unit is located inside the high-temperature and high-pressure reactor; the temperature measuring unit is connected to the high-temperature and high-pressure reactor; and the regulating unit collects the temperature measured by the temperature measuring unit and controls the heating intensity of the heating unit to adjust the temperature of the high-temperature and high-pressure reactor.
39. The testing equipment for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 38, wherein, The hydrogen sulfide tank is equipped with a pressure regulator at its opening.
40. The testing equipment for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 38, wherein, The hydrogen sulfide tank is equipped with a pressure-reducing valve at its opening, which controls a needle valve and a check valve.
41. The testing equipment for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 38, wherein, The testing equipment also includes a carbon dioxide tank, which is connected to the pipeline connecting the hydrogen sulfide tank and the high-temperature and high-pressure reactor via a tee.
42. The testing equipment for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 38, wherein, The testing equipment also includes a hydrogen sulfide absorption device, with one end of the gas discharge pipeline connected to the high-temperature and high-pressure reactor and the other end connected to the hydrogen sulfide absorption device.
43. The testing equipment for the adaptability of water-based completion fluid in hydrogen sulfide-containing crude oil according to claim 42, wherein, The hydrogen sulfide absorption device contains a sodium hydroxide solution.