Carbon dioxide dynamic water-rock reaction measuring device and measuring method

Abstract

The invention relates to the technical field of oil and gas reservoirs, and discloses a carbon dioxide dynamic water-rock reaction measuring device and method.According to the method, five groups of rock samples from the same well and with the same well depth are adopted for a parallel control experiment, the five groups of rock samples correspond to five reaction times set by the experiment respectively, and after each reaction is finished, the reaction time is calculated; according to the method, the porosity, permeability, mineral components and clay mineral components of corresponding rock samples are measured, the fluid ion concentration after the reaction is measured and analyzed, the carbon dioxide burying amount is calculated, experiments of other groups are not interfered, the reaction continuity and the reaction system sealing performance can be guaranteed, and the stratum reaction environment can be simulated more truly.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas reservoirs, and in particular to a device and method for measuring dynamic water-rock reaction of carbon dioxide. Background Art

[0002] The storage and utilization of carbon dioxide in oil and gas reservoirs can effectively improve the recovery rate of oil and gas reservoirs on the one hand, and effectively seal carbon dioxide in underground reservoirs on the other hand. It is a dual measure with both economic benefits and social and environmental effects. After being injected into oil and gas reservoirs, carbon dioxide will interact with formation water and reservoir rocks, causing mineral dissolution and precipitation. The dissolution of mineral components and ion reaction precipitation will cause changes in the pore structure of the reservoir. Accurately characterizing the impact of water-rock reaction on reservoir porosity and permeability is of great significance for evaluating changes in reservoir seepage capacity and sealing effects. Experimental determination of the impact of water-rock reaction on reservoirs is currently a common research method.

[0003] Prior art CN 110320339A provides a water-rock reaction device and operation method for simulating a closed formation environment. The device uses two reactors, the first reactor replenishes the reaction fluid, and the second reactor collects the fluid after the reaction, attempting to close the reaction environment to simulate the real reaction environment of the formation. However, when the fluid of the first reactor is replenished to the second reactor to continue the water-rock reaction, the fluid composition of the second reactor changes, and the real water environment of the water-rock reaction formation cannot be restored. Technology CN 109459362A discloses an integrated test device and method for high-temperature and high-pressure water-rock reaction and gas permeability, which can simulate the real high-temperature and high-pressure environment of the formation, and can directly measure the gas permeability of the core after the water-rock reaction. The device can more conveniently and safely measure the physical property changes of the water-rock reaction rock. Since the high-temperature and high-pressure water-rock reaction is a long-term dynamic change, this technology can only measure the physical property changes of the core after a single reaction stage, and cannot study the impact of the water-rock reaction on the rock over time. Technology CN 117269221 A proposes a nuclear magnetic resonance-based high-temperature and high-pressure water-rock reaction device and testing method. This technology uses nuclear magnetic resonance scanning to monitor the changes in rock pore throat distribution during the water-rock reaction process in real time. However, the dynamic changes in permeability during the water-rock reaction process and the changes in reservoir minerals and ion composition in the formation cannot be dynamically characterized.

[0004] Therefore, how to accurately characterize the dynamic changes in reservoir physical properties after carbon dioxide is injected into the formation in order to accurately evaluate the reservoir stability during the carbon dioxide storage process is a technical problem that urgently needs to be solved. Summary of the invention

[0005] The purpose of the present invention is to provide a carbon dioxide dynamic water-rock reaction measuring device and a measuring method, which aims to accurately restore the reservoir fluid configuration relationship after carbon dioxide is injected into the formation, measure the changes in formation water ion components, core permeability, porosity, mineral composition and clay mineral content at different water-rock reaction stages, and accurately evaluate the carbon dioxide mineralization storage capacity.

[0006] In order to achieve the above purpose, the technical solutions adopted are as follows:

[0007] In a first aspect, the present invention provides a carbon dioxide dynamic water-rock reaction measuring device, comprising an injection pump, a constant pressure pump, a formation water container, and a formation water intermediate container, wherein the injection pump is connected to the carbon dioxide intermediate container, a first helium intermediate container, and a second nitrogen intermediate container through a pipeline; a heating device is arranged on the outer side of the second nitrogen intermediate container, the carbon dioxide intermediate container is connected to a solution dispenser through a pipeline, a heating module and a rotary control button are arranged on the solution dispenser, the rotary control button is connected to the heating module to control the power of the heating module, the solution dispenser is connected to a first liquid collecting device and a first six-way valve through a pipeline, the first helium intermediate container and the second nitrogen intermediate container are connected to the first six-way valve through a pipeline, the constant pressure pump is connected to the formation water intermediate container through a pipeline, the formation water intermediate container is connected to the solution dispenser through a pipeline, the formation water container is connected to the connecting pipeline between the carbon dioxide intermediate container and the solution dispenser through a pipeline, a first pressure gauge is arranged on the connecting pipeline between the carbon dioxide intermediate container and the solution dispenser, the solution dispenser is connected to the first six-way valve and the first liquid collecting device through a pipeline The first liquid collecting device is connected to the first drainage and gas production device through a pipeline, the first six-way valve is respectively connected to the first temperature sensor, the second six-way valve and the ball valve through pipelines, a second pressure gauge is arranged on the connecting pipeline between the first six-way valve and the first temperature sensor, the ball valve is connected to the reference chamber and the constant temperature box through a pipeline, the second temperature sensor and the third pressure gauge are arranged outside the constant temperature box, the first core clamp, the second core clamp, the third core clamp, the fourth core clamp and the fifth core clamp are arranged inside the constant temperature box, the reference chamber is sequentially connected through pipelines The first core clamp, the second core clamp, the third core clamp, the fourth core clamp and the fifth core clamp are connected, and the first core clamp, the second core clamp, the third core clamp, the fourth core clamp and the fifth core clamp are all connected to a confining pressure pump. The outer side of the thermostatic box is connected to a back pressure valve and a back pressure pump through a pipeline. The back pressure valve is connected to a second liquid collecting device, a vacuum pump, anhydrous calcium chloride and an electronic flow meter through a pipeline. The anhydrous calcium chloride is arranged on the upper end of the electronic balance. The second liquid collecting device is connected to a second water drainage and gas production device through a pipeline.

[0008] Further, it also includes a valve assembly, which includes eighteen valves, namely a first valve, a second valve, a third valve, a fourth valve, a fifth valve, a sixth valve, a seventh valve, an eighth valve, a ninth valve, a tenth valve, an eleventh valve, a twelfth valve, a thirteenth valve, a fourteenth valve, a fifteenth valve, a sixteenth valve, a seventeenth valve and an eighteenth valve; wherein:

[0009] A first valve and a second valve are provided on a connecting pipe between the carbon dioxide intermediate container and the solution dispenser and a connecting pipe between the formation water container;

[0010] A third valve and a fourth valve are respectively provided on the connecting pipes of the first helium intermediate container and the second nitrogen intermediate container and the first six-way valve;

[0011] A fifth valve is provided on the connecting pipe between the formation water intermediate container and the solution dispenser;

[0012] A sixth valve is provided on the connecting pipe between the solution dispenser and the first liquid collecting device;

[0013] A seventh valve is provided on the connecting pipe between the first liquid collecting device and the first drainage and gas collecting device;

[0014] An eighth valve is provided on the connecting pipe between the first six-way valve and the first temperature sensor;

[0015] The first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder are connected through a circulation pipeline, and a ninth valve, a tenth valve, an eleventh valve, a twelfth valve and a thirteenth valve are respectively arranged on the circulation pipeline corresponding to the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder;

[0016] A fourteenth valve is arranged on one side of the back-pressure valve, a fifteenth valve is arranged on the connecting pipe between the back-pressure valve and the second liquid collecting device, a sixteenth valve is arranged on the connecting pipe between the second liquid collecting device and the second water drainage and gas production device, a seventeenth valve is arranged on the connecting pipe between the back-pressure valve and anhydrous calcium chloride, and an eighteenth valve is arranged on the connecting pipe between the back-pressure valve and the vacuum pump.

[0017] In a second aspect, the present invention provides a measurement method based on the above-mentioned carbon dioxide dynamic water-rock reaction measurement device, the measurement method comprising:

[0018] Step 1, preparing rock samples to obtain a first rock sample, a second rock sample, a third rock sample, a fourth rock sample and a fifth rock sample;

[0019] Step 2, respectively loading the first rock sample, the second rock sample, the third rock sample, the fourth rock sample and the fifth rock sample into the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder, starting the confining pressure pump and opening the valve of the corresponding pipeline to load the confining pressure to the core holder to the experimental value, and then turning on the vacuum pump to evacuate the core;

[0020] Step 3, preparing carbon dioxide saturated formation water;

[0021] Step 4, collecting the fluid before reaction;

[0022] Step 5, carrying out a carbon dioxide water-rock reaction;

[0023] Step 6, collecting the post-reaction fluid;

[0024] Step 7, measuring the gas permeability of the rock sample: open the second nitrogen intermediate container and the corresponding pipeline valve of the first core holder 31, open the heating device, fully heat the nitrogen to 120°C, then open the third valve, use the high-temperature nitrogen to displace the first core holder, when the electronic balance reading no longer changes, it means that the outlet gas no longer contains water vapor, indicating that the core has been dried, adjust the inlet of the first core holder to constant pressure nitrogen drive, turn on the back pressure pump and the back pressure valve, set the specified back pressure at the outlet, form a stable pressure difference at both ends of the first core holder, read the gas flow rate passing through the core per unit time through the electronic flow meter, and calculate the core gas permeability using the following formula:

[0025]

[0026] Where:

[0027] K-gas permeability, unit is μm 2 ;

[0028] p0-atmospheric pressure, in MPa;

[0029] p1-inlet pressure, in MPa;

[0030] p2- outlet pressure, in MPa;

[0031] μ-gas viscosity, in mPa·s;

[0032] L-core length, in cm;

[0033] d-core diameter, in cm;

[0034] Q0-gas volume flow rate, in mL / s;

[0035] Step 8, when the gas permeability of the core is greater than the liquid permeability, the Krebs permeability of the rock sample is calculated based on the gas permeability model;

[0036] Step 9, measuring the porosity of the rock sample;

[0037] Step 10, measuring the mineral components of the rock samples before and after the reaction by X-ray diffraction, after measuring the porosity, taking out the first rock sample, cutting the rock sample of a set length, grinding the two rock samples of the set length before and after the reaction into powder, measuring the mineral components and clay mineral components thereof by X-ray diffraction, and comparing and analyzing the mineral changes;

[0038] Step 11. After the first set of rock sample experiments are completed, steps 1 to 10 are repeated according to the different reaction stages set in the experiment until four sets of experimental measurements are completed. By comparing the porosity, permeability, ion concentration changes, mineral composition changes and storage capacity at different reaction times, the impact of water-rock reaction on the reservoir and mineralized storage capacity is comprehensively evaluated.

[0039] Furthermore, the rock sample preparation includes: taking samples from the same well and the same well section, the porosity and permeability deviations of the samples do not exceed 5%, the sample length is 12 cm, the diameter is 2.54 cm, the number of samples is 5, and each sample is cut into two sections of 2 cm and 10 cm.

[0040] Further, the configuration of carbon dioxide saturated formation water includes:

[0041] Inject formation water into the solution dispenser at a constant speed through the intermediate container, start the solution dispenser heating module, heat the solution dispenser to the formation temperature, set the constant temperature condition, and then, under the control of the injection pump, inject carbon dioxide into the solution dispenser at a constant pressure through the carbon dioxide intermediate container. When the temperature of the solution dispenser stabilizes at the formation temperature and the first pressure gauge reaches the formation pressure, close the fifth valve, start the heating module of the solution dispenser and rotate the control button, stir under the formation temperature and pressure conditions until the formation fluid state is reached. After the solution is prepared, the liquid dispenser is placed vertically.

[0042] Further, the collecting of pre-reaction fluid comprises:

[0043] Open the liquid collection device and the corresponding valves, collect the configured saturated carbon dioxide formation water, determine the ion components of the saturated carbon dioxide formation water, measure the volume of carbon dioxide through the drainage and gas production device, and calculate the solubility of carbon dioxide.

[0044] Further, the carrying out of the carbon dioxide water-rock reaction comprises:

[0045] Open the first six-way valve, inject the configured saturated carbon dioxide formation water into the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder, and increase the pressure to the formation pressure, then close the first six-way valve, open the thermostat 30, adjust the temperature to the experimental setting value, and start the carbon dioxide water-rock reaction.

[0046] Furthermore, the collecting of the post-reaction fluid comprises: when the reaction reaches a set first time cutoff point, opening the second liquid collecting device and the corresponding pipeline valve, collecting the post-reaction fluid and determining the ion composition and concentration, and using the second drainage and gas collection device to measure the volume of carbon dioxide, determining the current solubility of carbon dioxide, and analyzing the changes in the ion composition and ion concentration of the fluid before and after the reaction in combination with step 4, and calculating the carbon dioxide storage amount;

[0047] Furthermore, when the gas permeability of the core is greater than the liquid permeability, the absolute permeability of the rock sample is calculated based on the gas permeability model, including:

[0048] Perform multiple experiments under different average pressures and calculate the gas permeability according to the following formula:

[0049]

[0050] Determine Kg and Relationship:

[0051]

[0052] Where:

[0053] K ∞ Indicates absolute permeability in μm 2 ;

[0054] Kg represents the gas permeability, the unit is μm 2 ;

[0055] Indicates the average pressure at the core inlet and outlet, in MPa;

[0056] b represents a constant that depends on the gas properties and the rock pore structure;

[0057] Plot Kg vs. Relationship curve, where Kg and There is a straight line relationship between them, and the intercept of the straight line relationship on the Kg axis is K ∞ , that is, the absolute permeability of rock.

[0058] Further, measuring the porosity of the rock sample includes:

[0059] Close the valve of the first nitrogen intermediate container, open the vacuum to evacuate the first core holder, then close the vacuum pump, open the first helium intermediate container and the corresponding pipeline valve of the first rock sample, inject helium into the reference chamber, read the data T1 of the first temperature sensor and the data P1 of the second pressure gauge and record the data, then open the second six-way valve, diffuse the reference chamber gas to the first core holder, read the data T2 of the second temperature sensor and the data P2 of the third pressure gauge 42 and record the data, and calculate the porosity by the following formula:

[0060]

[0061] Where:

[0062] P1 represents the initial absolute pressure of the reference chamber;

[0063] P2 represents the absolute pressure after expansion;

[0064] P a represents the initial absolute atmospheric pressure in the rock sample;

[0065] z1 represents the gas deviation factor at P1 and T1;

[0066] z2 represents the gas deviation factor at P2 and T2;

[0067] T 1r represents the absolute temperature of the reference chamber at P1;

[0068] T1 means P a The absolute temperature of the pore space of the rock sample at that time;

[0069] T2 represents the absolute temperature of the rock sample and the reference chamber after P2 equilibrium;

[0070] V r represents the volume of the reference chamber;

[0071] V p represents the pore volume of the rock sample;

[0072] V v represents the valve displacement volume;

[0073] V d Represents the system dead volume.

[0074] The beneficial effects of the present invention are:

[0075] The present invention uses five groups of rock samples from the same well and the same well depth to conduct parallel control experiments. The five groups of rock samples correspond to five reaction times set in the experiment. After each reaction, the porosity, permeability, mineral composition and clay mineral composition of the corresponding rock samples are measured, and the fluid ion concentration after the reaction is measured and analyzed, and the carbon dioxide storage capacity is calculated. It will not interfere with the experiments of other groups, can ensure the continuity of the reaction and the closedness of the reaction system, and more realistically simulate the formation reaction environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 A structural diagram of a device for measuring dynamic water-rock reaction of carbon dioxide according to an embodiment of the present invention is shown.

[0077] Figure 2 A flow chart of a measurement method according to an embodiment of the present invention is shown.

[0078] Reference numerals:

[0079] 1-injection pump; 2-carbon dioxide intermediate container; 3-first helium intermediate container; 4-second nitrogen intermediate container; 5-heating device; 6-constant pressure pump; 7-formation water container; 8-first valve; 9-formation water intermediate container; 10-second valve; 11-third valve; 12-fourth valve; 13-fifth valve; 14-first pressure gauge; 15-solution dispenser; 16-heating module; 17-rotation control button; 18-sixth valve; 19-first liquid collection device; 20-seventh valve; 21-first drainage and gas production device; 22-first six-way valve; 23-second pressure gauge; 24-eighth valve; 25-first temperature sensor; 26-reference chamber; 27-second six-way valve; 28-spherical valve; 2 9-second temperature sensor; 30-constant temperature box; 31-first core holder; 32-second core holder; 33-third core holder; 34-fourth core holder; 35-fifth core holder; 36-ninth valve; 37-tenth valve; 38-eleventh valve; 39-twelfth valve; 40-thirteenth valve; 41-confining pressure pump; 42-third pressure gauge; 43-back pressure pump; 44-back pressure valve; 45-fourteenth valve; 46-fifteenth valve; 47-second liquid collecting device; 48-sixteenth valve; 49-second drainage and gas production device; 50-electronic balance; 51-anhydrous calcium chloride; 52-seventeenth valve; 53-electronic flow meter; 54-eighteenth valve; 55-vacuum pump. DETAILED DESCRIPTION

[0080] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0081] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0082] Figure 1 The structure diagram of a carbon dioxide dynamic water-rock reaction measuring device according to an embodiment of the present invention is shown. The embodiment of the present invention provides a carbon dioxide dynamic water-rock reaction measuring device, please refer to Figure 1The carbon dioxide dynamic water-rock reaction measuring device comprises an injection pump 1, a constant pressure pump 6, a formation water container 7, and a formation water intermediate container 9. The injection pump is connected to a carbon dioxide intermediate container 2, a first helium intermediate container 3, and a second nitrogen intermediate container 4 through a pipeline; a heating device 5 is arranged on the outer side of the second nitrogen intermediate container 4; the carbon dioxide intermediate container 2 is connected to a solution dispenser 15 through a pipeline; a heating module 16 and a rotary control button 17 are arranged on the solution dispenser 15; the rotary control button 17 is connected to the heating module 16 to control the power of the heating module 16; the solution dispenser 15 is connected to a first liquid collecting device 19 and a second liquid collecting device 19 through a pipeline. The first six-way valve 22, the first helium intermediate container 3 and the second nitrogen intermediate container 4 are connected to the first six-way valve 22 through a pipeline, the constant pressure pump 6 is connected to the formation water intermediate container 9 through a pipeline, the formation water intermediate container 9 is connected to the solution dispenser 15 through a pipeline, the formation water container 7 is connected to the connecting pipeline between the carbon dioxide intermediate container 2 and the solution dispenser 15 through a pipeline, the connecting pipeline between the carbon dioxide intermediate container 2 and the solution dispenser 15 is provided with a first pressure gauge 14, the solution dispenser 15 is connected to the first six-way valve 22 and the first liquid collecting device 19 through a pipeline, and the first liquid collecting device 19 is connected to the first water drainage and gas extraction device 21 through a pipeline, The first six-way valve 22 is connected to the first temperature sensor 25, the second six-way valve 27 and the ball valve 28 through pipelines, the second pressure gauge 23 is arranged on the connecting pipeline between the first six-way valve 22 and the first temperature sensor 25, the ball valve 28 is connected to the reference chamber 26 and the constant temperature box 30 through pipelines, the second temperature sensor 29 and the third pressure gauge 42 are arranged outside the constant temperature box 30, the first core clamp 31, the second core clamp 32, the third core clamp 33, the fourth core clamp 34 and the fifth core clamp 35 are arranged inside the constant temperature box 30, the reference chamber 26 is connected to the first core clamp 31, the second core clamp 32, the third core clamp 33, the fourth core clamp 34 and the fifth core clamp 35 in sequence through pipelines The first core holder 31, the second core holder 32, the third core holder 33, the fourth core holder 34 and the fifth core holder 35, the first core holder 31, the second core holder 32, the third core holder 33, the fourth core holder 34 and the fifth core holder 35 are all connected to a confining pressure pump 41, the outside of the constant temperature box 30 is connected to a back pressure valve 44 and a back pressure pump 43 through a pipeline, the back pressure valve 44 is connected to a second liquid collecting device 47, a vacuum pump 55, anhydrous calcium chloride 51 and an electronic flow meter 53 through a pipeline, the anhydrous calcium chloride 51 is arranged on the upper end of the electronic balance 50, and the second liquid collecting device 47 is connected to a second water drainage and gas production device 49 through a pipeline.

[0083] In some embodiments, the carbon dioxide dynamic water-rock reaction measuring device also includes a valve assembly, which includes eighteen valves, namely a first valve 8, a second valve 10, a third valve 11, a fourth valve 12, a fifth valve 13, a sixth valve 18, a seventh valve 20, an eighth valve 24, a ninth valve 36, a tenth valve 37, an eleventh valve 38, a twelfth valve 39, a thirteenth valve 40, a fourteenth valve 45, a fifteenth valve 46, a sixteenth valve 48, a seventeenth valve 52 and an eighteenth valve 54; wherein: the first valve 8 and the second valve 10 are arranged on the connecting pipeline between the carbon dioxide intermediate container 2 and the solution dispenser 15 and the connecting pipeline between the formation water container 7; the third valve 11 and the fourth valve 12 are respectively arranged on the connecting pipeline between the first helium intermediate container 3 and the second nitrogen intermediate container 4 and the first six-way valve 22; the fifth valve 13 is arranged on the connecting pipeline between the formation water intermediate container 9 and the solution dispenser 15; the sixth valve 18 is arranged on the connecting pipeline between the solution dispenser 15 and the first liquid collecting device 19; the first liquid collecting device 19 and A seventh valve 20 is provided on the connecting pipe of the first water drainage and gas production device 21; an eighth valve 24 is provided on the connecting pipe between the first six-way valve 22 and the first temperature sensor 25; the first core clamp 31, the second core clamp 32, the third core clamp 33, the fourth core clamp 34 and the fifth core clamp 35 are connected through a circulation pipe, and the first core clamp 31, the second core clamp 32, the third core clamp 33, the fourth core clamp 34 and the fifth core clamp 35 are provided on the circulation pipe. A ninth valve 36, a tenth valve 37, an eleventh valve 38, a twelfth valve 39 and a thirteenth valve 40; a fourteenth valve 45 is arranged on one side of the back pressure valve 44, a fifteenth valve 46 is arranged on the connecting pipe between the back pressure valve 44 and the second liquid collecting device 47, a sixteenth valve 48 is arranged on the connecting pipe between the second liquid collecting device 47 and the second drainage and gas collection device 49, a seventeenth valve 52 is arranged on the connecting pipe between the back pressure valve 44 and the anhydrous calcium chloride 51, and an eighteenth valve 54 is arranged on the connecting pipe between the back pressure valve 44 and the vacuum pump 55.

[0084] In some embodiments, the present invention also provides a measurement method, such as Figure 2 FIG. 1 is a flow chart of the measurement method, which is based on the carbon dioxide dynamic water-rock reaction measurement device as described above and includes the following steps:

[0085] Step 1, rock sample preparation. Rock sample sampling requirements: taken from the same well and the same well section, porosity and permeability deviation does not exceed 5%, which can reduce the error caused by reservoir heterogeneity. The sample length is 12cm, the diameter is 2.54cm, and the number of samples is 5. Cut each sample into 2cm and 10cm sections.

[0086] Step 2, rock sample equipment. Five groups of rock samples are loaded into five core holders 31-35 respectively, and then the confining pressure pump 41 is started and the valves of the corresponding pipelines are opened to load the confining pressure to the core holders to the experimental value, and then the vacuum pump is turned on to evacuate the cores.

[0087] Step 3, prepare saturated carbon dioxide formation water. First, inject 200mL of formation water into the solution preparer 15 at a constant rate through the intermediate container 9. Start the solution preparer heating module 16, heat the solution preparer temperature to the formation temperature, and set the constant temperature condition. Then, under the control of the injection pump 1, inject carbon dioxide into 15 at a constant pressure through the carbon dioxide intermediate container 2. When the solution preparer temperature stabilizes at the formation temperature and the pressure gauge 14 reaches the formation pressure, close the valve 13. Start the heating module and the rotary button 17 of the solution preparation container 15, and stir for 2 hours under the formation temperature and pressure conditions until the formation fluid state is reached. After the solution preparation is completed, the liquid preparer is placed vertically.

[0088] Step 4, collecting the fluid before the reaction. Open the liquid collection device 19 and the corresponding valves, collect the prepared saturated carbon dioxide formation water, determine its ion components, measure the carbon dioxide volume through the drainage gas collection device 21, and calculate the carbon dioxide solubility.

[0089] Step 5, conduct the carbon dioxide water-rock reaction. Open the first six-way valve 22, inject the prepared saturated carbon dioxide formation water into the five core holders, and raise the pressure to the formation pressure, then close the first six-way valve. Open the thermostat 30, adjust the temperature to the experimental setting value, and start the carbon dioxide water-rock reaction.

[0090] Step 6, collect the fluid after the reaction. When the reaction reaches the set first time cutoff point, open the liquid collection device 47 and the corresponding pipeline valve, collect the fluid after the reaction and determine the ion composition and concentration, and use the drainage gas collection device 49 to measure the volume of carbon dioxide. Determine the current solubility of carbon dioxide. Combined with step 4, analyze the changes in the ion composition and ion concentration of the fluid before and after the reaction, and calculate the carbon dioxide storage capacity.

[0091] Step 7, measure the gas permeability of the rock sample. Open the nitrogen intermediate container 4, the corresponding pipeline valve of the first core clamp 31, open the nitrogen bottle heating device 5, fully heat the nitrogen to 120°C, and then open the valve 11 to use the high-temperature nitrogen to displace the first core clamp. When the reading of the electronic balance 50 no longer changes, it means that the outlet gas no longer contains water vapor, which means that the core has been dried. Adjust the inlet of the core clamp 31 to constant pressure nitrogen drive, open the back pressure pump 43 back pressure valve 44, set the specified back pressure at the outlet, form a stable pressure difference at both ends of the clamp 31, read the gas flow rate passing through the core per unit time through the electronic flowmeter 53, and calculate the core gas permeability using the following formula:

[0092]

[0093] Where:

[0094] K-gas permeability, unit is μm 2 ;

[0095] p0-atmospheric pressure, in MPa;

[0096] p1-inlet pressure, in MPa;

[0097] p2- outlet pressure, in MPa;

[0098] μ-gas viscosity, in mPa·s;

[0099] L-core length, in cm;

[0100] d-core diameter, in cm;

[0101] Q0-gas volume flow rate, in mL / s.

[0102] Step 8, Klinkenberg correction of gas permeability. Due to the gas sliding effect, the measured gas permeability is greater than the liquid permeability. The absolute permeability of the rock sample can be calculated by the gas permeability model given by Klinkenberg that takes into account the gas sliding effect. Perform experiments at 5 different average pressures, calculate Kg according to the following formula, and plot Kg vs. Relationship curve, Kg and The intercept of the straight line on the Kg axis is K ∞ , that is, the absolute permeability of rock.

[0103]

[0104] Where:

[0105] K ∞ Indicates absolute permeability in μm 2 ;

[0106] Kg represents the gas permeability, the unit is μm 2 ;

[0107] Indicates the average pressure at the core inlet and outlet, in MPa;

[0108] b represents a constant that depends on the properties of the gas and the pore structure of the rock.

[0109] Step 9, measure the porosity of the rock sample. Close the valve of the nitrogen intermediate container, open the vacuum pump 55 to evacuate the first core 31, then close the vacuum pump, open the helium intermediate container 3 and the valve of the corresponding pipeline of the first rock sample, inject helium into the reference chamber 26, read the data T1 of the first temperature sensor 25 and the data P1 of the second pressure gauge 23 and record the data, then open the second six-way valve 27 corresponding to the first core, diffuse the reference chamber gas to the first core holder, read the data T2 of the second temperature sensor 29 and the data P2 of the third pressure gauge 42 and record the data, and calculate the porosity by the following formula:

[0110]

[0111] Where:

[0112] P1 represents the initial absolute pressure of the reference chamber;

[0113] P2 represents the absolute pressure after expansion;

[0114] P a represents the initial absolute atmospheric pressure in the rock sample;

[0115] z1 represents the gas deviation factor at P1 and T1;

[0116] z2 represents the gas deviation factor at P2 and T2;

[0117] T 1r represents the absolute temperature of the reference chamber at P1;

[0118] T1 means P a The absolute temperature of the pore space of the rock sample at that time;

[0119] T2 represents the absolute temperature of the rock sample and the reference chamber after P2 equilibrium;

[0120] V r represents the volume of the reference chamber;

[0121] V p represents the pore volume of the rock sample;

[0122] V v represents the valve displacement volume;

[0123] V d Represents the system dead volume.

[0124] Step 10, measuring the mineral components of the rock samples before and after the reaction by X-ray diffraction. After measuring the porosity, take out the first rock sample, cut a 2 cm rock sample, grind the two 2 cm rock samples before and after the reaction into powder, measure their mineral components and clay mineral components by X-ray diffraction, and compare and analyze the mineral changes.

[0125] Step 11, complete the remaining four parallel experiments. After the first group of rock sample experiments are completed, according to the different reaction stages set in the experiment, repeat steps 1 to 10 until the four groups of experimental measurements are completed. By comparing the porosity, permeability, ion concentration changes, mineral composition changes and storage capacity at different reaction times, the impact of water-rock reaction on the reservoir and mineralization storage capacity is comprehensively evaluated.

[0126] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. A device for measuring the dynamic water-rock reaction of carbon dioxide, characterized in that: The invention comprises an injection pump, a constant pressure pump, a formation water container, and a formation water intermediate container. The injection pump is connected to a carbon dioxide intermediate container, a first helium intermediate container, and a second nitrogen intermediate container through a pipeline. A heating device is arranged on the outer side of the second nitrogen intermediate container. The carbon dioxide intermediate container is connected to a solution dispenser through a pipeline. A heating module and a rotary control button are arranged on the solution dispenser. The rotary control button is connected to the heating module to control the power of the heating module. The solution dispenser is connected to a first liquid collecting device and a first six-way valve through a pipeline. The first helium intermediate container and the second nitrogen intermediate container are connected to the first six-way valve through a pipeline. The constant pressure pump is connected to a formation water intermediate container through a pipeline. The formation water intermediate container is connected to the solution dispenser through a pipeline. The formation water container is connected to a connecting pipeline between the carbon dioxide intermediate container and the solution dispenser through a pipeline. A first pressure gauge is arranged on the connecting pipeline between the carbon dioxide intermediate container and the solution dispenser. The solution dispenser is connected to the first six-way valve and a first liquid collecting device through a pipeline. The first liquid collecting device is connected to the first six-way valve through a pipeline. The first six-way valve is connected to the first water drainage and gas production device through a pipeline, the first six-way valve is respectively connected to the first temperature sensor, the second six-way valve and the ball valve through pipelines, a second pressure gauge is arranged on the connecting pipeline between the first six-way valve and the first temperature sensor, the ball valve is connected to the reference chamber and the constant temperature box through a pipeline, a second temperature sensor and a third pressure gauge are arranged outside the constant temperature box, a first core holder, a second core holder, a third core holder, a fourth core holder and a fifth core holder are arranged inside the constant temperature box, the reference chamber is sequentially connected to the first core holder through pipelines, The invention relates to a core clamp, a second core clamp, a third core clamp, a fourth core clamp and a fifth core clamp, wherein the first core clamp, the second core clamp, the third core clamp, the fourth core clamp and the fifth core clamp are all connected to a confining pressure pump, the outer side of the thermostatic box is connected to a back pressure valve and a back pressure pump through a pipeline, the back pressure valve is connected to a second liquid collecting device, a vacuum pump, anhydrous calcium chloride and an electronic flow meter through a pipeline, the anhydrous calcium chloride is arranged on the upper end of the electronic balance, and the second liquid collecting device is connected to a second water drainage and gas production device through a pipeline.

2. The carbon dioxide dynamic water-rock reaction measuring device according to claim 1, characterized in that: The device also includes a valve assembly, which includes eighteen valves, namely a first valve, a second valve, a third valve, a fourth valve, a fifth valve, a sixth valve, a seventh valve, an eighth valve, a ninth valve, a tenth valve, an eleventh valve, a twelfth valve, a thirteenth valve, a fourteenth valve, a fifteenth valve, a sixteenth valve, a seventeenth valve and an eighteenth valve; wherein: A first valve and a second valve are provided on a connecting pipe between the carbon dioxide intermediate container and the solution dispenser and a connecting pipe between the formation water container; A third valve and a fourth valve are respectively provided on the connecting pipes of the first helium intermediate container and the second nitrogen intermediate container and the first six-way valve; A fifth valve is provided on the connecting pipe between the formation water intermediate container and the solution dispenser; A sixth valve is provided on the connecting pipe between the solution dispenser and the first liquid collecting device; A seventh valve is provided on the connecting pipe between the first liquid collecting device and the first drainage and gas collecting device; An eighth valve is provided on the connecting pipe between the first six-way valve and the first temperature sensor; The first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder are connected through a circulation pipeline, and a ninth valve, a tenth valve, an eleventh valve, a twelfth valve and a thirteenth valve are respectively arranged on the circulation pipeline corresponding to the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder; A fourteenth valve is arranged on one side of the back-pressure valve, a fifteenth valve is arranged on the connecting pipe between the back-pressure valve and the second liquid collecting device, a sixteenth valve is arranged on the connecting pipe between the second liquid collecting device and the second water drainage and gas production device, a seventeenth valve is arranged on the connecting pipe between the back-pressure valve and anhydrous calcium chloride, and an eighteenth valve is arranged on the connecting pipe between the back-pressure valve and the vacuum pump.

3. A measurement method based on the carbon dioxide dynamic water-rock reaction measurement device according to claim 2, characterized in that: The measuring method comprises: Step 1, preparing rock samples to obtain a first rock sample, a second rock sample, a third rock sample, a fourth rock sample and a fifth rock sample; Step 2, respectively loading the first rock sample, the second rock sample, the third rock sample, the fourth rock sample and the fifth rock sample into the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder, starting the confining pressure pump and opening the valve of the corresponding pipeline to load the confining pressure to the core holder to the experimental value, and then turning on the vacuum pump to evacuate the core; Step 3, preparing carbon dioxide saturated formation water; Step 4, collecting the fluid before reaction; Step 5, carrying out a carbon dioxide water-rock reaction; Step 6, collecting the post-reaction fluid; Step 7, measuring the gas permeability of the rock sample: open the second nitrogen intermediate container and the corresponding pipeline valve of the first core holder 31, open the heating device, fully heat the nitrogen to 120°C, then open the third valve, use the high-temperature nitrogen to displace the first core holder, when the electronic balance reading no longer changes, it means that the outlet gas no longer contains water vapor, indicating that the core has been dried, adjust the inlet of the first core holder to constant pressure nitrogen drive, turn on the back pressure pump and the back pressure valve, set the specified back pressure at the outlet, form a stable pressure difference at both ends of the first core holder, read the gas flow rate passing through the core per unit time through the electronic flow meter, and calculate the core gas permeability using the following formula: Where: K-gas permeability, unit is μm 2 ; p0-atmospheric pressure, in MPa; p1-inlet pressure, in MPa; p2- outlet pressure, in MPa; μ-gas viscosity, in mPa·s; L-core length, in cm; d-core diameter, in cm; Q0-gas volume flow rate, in mL / s; Step 8, when the gas permeability of the core is greater than the liquid permeability, the Krebs permeability of the rock sample is calculated based on the gas permeability model; Step 9, measuring the porosity of the rock sample; Step 10, measuring the mineral components of the rock samples before and after the reaction by X-ray diffraction, after measuring the porosity, taking out the first rock sample, cutting the rock sample of a set length, grinding the two rock samples of the set length before and after the reaction into powder, measuring the mineral components and clay mineral components thereof by X-ray diffraction, and comparing and analyzing the mineral changes; Step 11. After the first set of rock sample experiments are completed, steps 1 to 10 are repeated according to the different reaction stages set in the experiment until four sets of experimental measurements are completed. By comparing the porosity, permeability, ion concentration changes, mineral composition changes and storage capacity at different reaction times, the impact of water-rock reaction on the reservoir and mineralized storage capacity is comprehensively evaluated.

4. The measuring method according to claim 3, characterized in that: The rock sample preparation comprises: taking samples from the same well and the same well section, the porosity and permeability deviations of the samples do not exceed 5%, the sample length is 12 cm, the diameter is 2.54 cm, the number of samples is 5, and each sample is cut into two sections of 2 cm and 10 cm.

5. The measuring method according to claim 3, characterized in that: The configuration of carbon dioxide saturated formation water comprises: Inject formation water into the solution dispenser at a constant speed through the intermediate container, start the solution dispenser heating module, heat the solution dispenser to the formation temperature, set the constant temperature condition, and then, under the control of the injection pump, inject carbon dioxide into the solution dispenser at a constant pressure through the carbon dioxide intermediate container. When the temperature of the solution dispenser stabilizes at the formation temperature and the first pressure gauge reaches the formation pressure, close the fifth valve, start the heating module of the solution dispenser and rotate the control button, stir under the formation temperature and pressure conditions until the formation fluid state is reached. After the solution is prepared, the liquid dispenser is placed vertically.

6. The measuring method according to claim 3, characterized in that: The collecting of pre-reaction fluid comprises: Open the liquid collection device and the corresponding valves, collect the configured saturated carbon dioxide formation water, determine the ion components of the saturated carbon dioxide formation water, measure the volume of carbon dioxide through the drainage and gas production device, and calculate the solubility of carbon dioxide.

7. The measuring method according to claim 3, characterized in that: The carrying out of the carbon dioxide water-rock reaction comprises: Open the first six-way valve, inject the configured saturated carbon dioxide formation water into the first core holder, the second core holder, the third core holder, the fourth core holder and the fifth core holder, and increase the pressure to the formation pressure, then close the first six-way valve, open the thermostat 30, adjust the temperature to the experimental setting value, and start the carbon dioxide water-rock reaction.

8. The measuring method according to claim 3, characterized in that: The collecting of the post-reaction fluid comprises: when the reaction reaches a set first time cutoff point, opening a second liquid collecting device and a corresponding pipeline valve, collecting the post-reaction fluid and determining the ion composition and concentration, and using a second drainage and gas collection device to measure the volume of carbon dioxide, determining the current solubility of carbon dioxide, and analyzing the changes in the ion composition and ion concentration of the fluid before and after the reaction in combination with step 4, and calculating the carbon dioxide storage amount.

9. The measuring method according to claim 3, characterized in that: When the gas permeability of the core is greater than the liquid permeability, the absolute permeability of the rock sample is calculated based on the gas permeability model, including: Perform multiple experiments under different average pressures and calculate the gas permeability according to the following formula: Determine K as follows ∞ and Relationship: Where: K ∞ Indicates absolute permeability in μm 2 ; Kg represents the gas permeability, the unit is μm 2 ; Indicates the average pressure at the core inlet and outlet, in MPa; b represents a constant that depends on the gas properties and the rock pore structure; Plot Kg vs. Relationship curve, where Kg and There is a straight line relationship between them, and the intercept of the straight line relationship on the Kg axis is K ∞ , that is, the absolute permeability of rock.

10. The measuring method according to claim 3, characterized in that: The measuring of the rock sample porosity comprises: Close the valve of the first nitrogen intermediate container, open the vacuum to evacuate the first core holder, then close the vacuum pump, open the first helium intermediate container and the corresponding pipeline valve of the first rock sample, inject helium into the reference chamber, read the data T1 of the first temperature sensor and the data P1 of the second pressure gauge and record the data, then open the second six-way valve, diffuse the reference chamber gas to the first core holder, read the data T2 of the second temperature sensor and the data P2 of the third pressure gauge 42 and record the data, and calculate the porosity by the following formula: Where: P1 represents the initial absolute pressure of the reference chamber; P2 represents the absolute pressure after expansion; P a represents the initial absolute atmospheric pressure in the rock sample; z1 represents the gas deviation factor at P1 and T1; z2 represents the gas deviation factor at P2 and T2; T 1r represents the absolute temperature of the reference chamber at P1; T1 means P a The absolute temperature of the pore space of the rock sample at that time; T2 represents the absolute temperature of the rock sample and the reference chamber after P2 equilibrium; V r represents the volume of the reference chamber; V p represents the pore volume of the rock sample; V v represents the valve displacement volume; V d Represents the system dead volume.

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