Quantitative water-rock reaction experimental device and experimental method

Abstract

The invention provides a quantitative water-rock reaction experimental device and experimental method. By adopting the quantitative water-rock reaction experimental device provided by the invention and implementing the quantitative water-rock reaction experimental method provided by the invention, quantitative and qualitative simulation and real-time online monitoring, recording and storage can be carried out on the interreaction process from a deep stratum to surface stratum fluid and surrounding rock; effective means and methods are provided for exploring the deep carbonate reservoir formation mechanism and predicting the deep carbonate reservoir formation mechanism, and the method is suitable for application and popularization.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water-rock reaction process, and particularly relates to a quantitative water-rock reaction experimental device and experimental method. BACKGROUND

[0002] Deep-ultra deep marine carbonate rock is an important target field for present oil and gas exploration. Carbonate rock reservoir is more susceptible to fluid modification, thus forming secondary reservoir space. Fluid flows and migrates along the primary reservoir space of rock such as pores, holes and fractures, dissolves surrounding rock minerals, precipitates new minerals, and thus changes the pore space geometry and fluid flow path. The modified surrounding rock reservoir performance is improved or reduced. The source of fluid can be deep hydrothermal fluid, formation fluid or pore water. At present, the interaction between carbonate rock reservoir and formation fluid in surface-deep formation environment and the potential influence of these interactions on carbonate rock reservoir are not fully understood, and there is a lack of quantitative effective means for the development of this process, thus it is necessary to develop corresponding experimental device and method to carry out corresponding simulation experiment to find out.

[0003] The detection result of the existing water-rock chemical reaction device is to calculate the reaction kinetics parameters such as reaction rate after the reaction is completed, but it cannot monitor the kinetics parameters at a certain moment or at a certain reaction progress during the reaction process, cannot quantify the reaction process, and cannot meet the demand of exploring fluid-rock reaction process / mechanism. Therefore, a water-rock reaction device and corresponding experimental method are needed to quantitatively simulate and reproduce the reaction process of fluid modifying surrounding rock in surface-deep formation environment, to meet the demand of exploring fluid-rock reaction process / mechanism. SUMMARY

[0004] In view of the problems in the prior art that there is a lack of quantitative research means for the interaction between carbonate rock reservoir and formation fluid in surface-deep formation environment and the potential influence of these interactions on carbonate rock reservoir, and the existing water-rock reaction device cannot quantify the reaction process and cannot meet the technical demand of exploring fluid-rock reaction process / mechanism, the purpose of the present application is to provide a quantitative water-rock reaction experimental device and experimental method, which quantitatively controls the reaction progress of water-rock reaction at a stable reaction rate, supports monitoring the kinetics parameters at a certain moment or at a certain reaction progress during the water-rock reaction process, and meets the technical demand of exploring fluid-rock reaction process / mechanism.

[0005] To achieve the above-mentioned purpose, one of the present application provides a quantitative water-rock reaction experimental device, which comprises a reaction device 10 and a computer 50, and a carbon dioxide input device 20, a reaction fluid input device 30 and a chemical signal acquisition device 40 connected with the reaction device 10 and the computer 50 respectively; wherein,

[0006] The reaction device 10 contains basic fluid and rock sample, and provides a place for water-rock reaction;

[0007] The carbon dioxide input device 20 is used for controllably delivering carbon dioxide to the reaction device 10;

[0008] The reaction fluid input device 30 is used for automatically metering the reaction fluid to the reaction device 10 in real time;

[0009] The chemical signal collection device 40 is used for collecting chemical signals in real time;

[0010] The computer 50 is used for acquiring the chemical signals in real time and the delivery amount of the reaction fluid, and controlling the carbon dioxide input device 20 and the reaction fluid input device 30, so as to realize quantitative control of reaction progress and stable maintenance of reaction rate.

[0011] According to the present application, the carbon dioxide input device 20 comprises a gas inlet pipeline 201, and a first constant pressure and constant flow pumping device 202 and a first stop valve 203 arranged in sequence on the gas inlet pipeline 201 along the carbon dioxide delivery direction; and / or

[0012] The reaction fluid input device 30 comprises an automatic metering liquid inlet pipeline 301, and a second constant pressure and constant flow pumping device 302 and a second stop valve 303 arranged in sequence on the automatic metering liquid inlet pipeline 301 along the reaction fluid delivery direction; wherein the automatic metering liquid inlet pipeline 301 is used for automatically metering the amount of the reaction fluid pumped to the reaction device 10 in real time.

[0013] According to the present application, the automatic metering liquid inlet pipeline 301, the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 are connected with the computer 50 respectively.

[0014] According to the present application, the computer 50 is configured to calculate a first target amount of the reaction fluid required for quantitatively controlling the water-rock reaction at a target reaction progress, and automatically acquire the amount of the reaction fluid pumped to the reaction device 10 in real time from the automatic metering liquid inlet pipeline 301;

[0015] When the amount of the reaction fluid pumped to the reaction device 10 by the second constant pressure and constant flow pumping device 302 reaches the first target amount, the computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to be closed, stops pumping carbon dioxide and the reaction fluid to the reaction device 10, closes the first stop valve 203 and the second stop valve 303, and stops the reaction.

[0016] According to the present application, the chemical signal acquisition at least includes real-time hydrogen ion concentration acquisition in the reaction system in the reaction device 10.

[0017] According to the present application, the computer 50 is further configured to set a target pH value corresponding to a target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid.

[0018] According to the present application, the computer 50 is further configured to automatically acquire the real-time hydrogen ion concentration from the chemical signal acquisition device 40 and automatically convert it into a real-time pH value, compare the real-time pH value with the target pH value, automatically calculate a second target amount of the reaction fluid required to adjust the real-time pH value to the target pH value when the real-time pH value exceeds the target pH value, and automatically control the second constant pressure and constant flow pumping device 302 to pump the second target amount of the reaction fluid into the reaction device 10 through the automatic metering liquid inlet pipeline 301.

[0019] According to the present application, during the pumping of the reaction fluid into the reaction device 10, the automatic metering liquid inlet pipeline 301 automatically meters the pumped amount of the reaction fluid, the chemical signal acquisition device 40 acquires the real-time hydrogen ion concentration of the reaction system, until the computer 50 acquires the pumped amount of the reaction fluid from the automatic metering liquid inlet pipeline 301 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration acquired from the chemical signal acquisition device 40 reaches the target pH value, so as to maintain the stability of the reaction rate.

[0020] According to the present application, the quantitative water-rock reaction experimental device further comprises a separation device 60, which is connected with the reaction device 10 through a liquid outlet pipeline 101, and is used to collect post-reaction solution and post-reaction rock sample from the post-reaction fluid for subsequent analysis and testing.

[0021] A back pressure valve 102 and a third shut-off valve 103 are further arranged on the liquid outlet pipeline 101 respectively at positions close to the inlet and outlet of the separation device 60.

[0022] According to the present application, the base fluid is a sodium chloride-calcium chloride mixed solution; and / or the reaction fluid is an acid solution.

[0023] Preferably, the salinity of the sodium chloride-calcium chloride mixed solution is the same as that of seawater; and / or

[0024] The acid solution is dilute hydrochloric acid.

[0025] The second aspect of the present application provides a quantitative water-rock reaction experimental method, which is realized by the quantitative water-rock reaction experimental device according to the first aspect of the present application, and comprises the following steps:

[0026] S1. In the reaction device 10, the base fluid and the rock sample are added, carbon dioxide is controllably delivered into the reaction device 10 through the carbon dioxide input device 20, and the reaction fluid is automatically metered into the reaction device 10 in real time through the reaction fluid input device 30, and the water-rock reaction is carried out;

[0027] S2. In the process of the water-rock reaction, the reaction device 10 is subjected to real-time chemical signal acquisition through the chemical signal acquisition device 40, and the reaction rate is maintained stable under the control of the computer 50 in cooperation with the reaction fluid input device 30;

[0028] S3. The computer 50 is used to acquire real-time chemical signals and the delivery amount of the reaction fluid, control the carbon dioxide input device 20 and the reaction fluid input device 30 to deliver carbon dioxide and the reaction fluid into the reaction device 10 respectively, and quantitatively control the reaction progress; when the water-rock reaction reaches the target reaction progress, the reaction is stopped, and sampling is carried out for subsequent analysis and testing.

[0029] According to the present application, the computer 50 is used to calculate a first target amount of the reaction fluid required for quantitatively controlling the water-rock reaction at the target reaction progress; and / or a target pH value corresponding to a target reaction rate is set according to the first kinetics between the rock sample and the reaction fluid;

[0030] Then, the step S1 is carried out again.

[0031] According to the present application, in the step S1, the back pressure valve 102, the third stop valve 103, and the first stop valve 203 are opened, the first constant pressure and constant flow pumping device 202 is started, carbon dioxide is pumped into the reaction device 10 through the gas inlet pipeline 201; synchronously, the second stop valve 303 is opened, the second constant pressure and constant flow pumping device 302 is started, and the reaction fluid is pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301; the automatic metering liquid inlet pipeline 301 automatically meters the pumping amount of the reaction fluid.

[0032] According to the present application, in the step S2, the real-time hydrogen ion concentration of the reaction system in the reaction device 10 is acquired by the chemical signal acquisition device 40; the computer 50 is used to acquire the real-time hydrogen ion concentration from the chemical signal acquisition device 40 and automatically convert the real-time hydrogen ion concentration into a real-time pH value; the real-time pH value is automatically compared with the target pH value, and when the real-time pH value exceeds the target pH value, a second target amount of the reaction fluid required for adjusting the pH to the target pH value is automatically calculated;

[0033] Under the automatic control of the computer 50, the second target amount of the reaction fluid is pumped into the reaction device 10 through the second constant pressure and constant flow pumping device 302 via the automatic metering liquid inlet pipeline 301.

[0034] According to the present application, during the pumping of the reaction fluid, the pumped amount of the reaction fluid is automatically metered in real time by the automatic metering liquid inlet pipeline 301, and the real-time hydrogen ion concentration in the reaction system is collected by the chemical signal collection device 40; until the pumped amount of the reaction fluid obtained by the computer 50 from the automatic metering liquid inlet pipeline 301 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained by the chemical signal collection device 40 reaches the target pH value, the reaction rate of the water-rock reaction is maintained at the target reaction rate.

[0035] According to the present application, in step S3, the amount of the reaction fluid pumped into the reaction device 10 is obtained by the computer 50 from the automatic metering liquid inlet pipeline 301, and when the first target amount is reached, it represents that the water-rock reaction reaches the target reaction progress; the computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to close, stops pumping carbon dioxide and the reaction fluid into the reaction device 10, closes the first stop valve 203 and the second stop valve 303, and stops the reaction.

[0036] According to the present application, in step S3, after the reaction is stopped, the post-reaction fluid is transported to the separation device 60 via the liquid outlet pipeline 101 for solid-liquid separation, and the post-reaction solution and the post-reaction rock sample are collected.

[0037] According to the present application, in step S3, the subsequent analysis test includes detecting the hydrogen ion concentration in the post-reaction solution and the metal cation concentration contained in the rock sample; and / or

[0038] The surface morphology of the post-reaction rock sample is observed and the mineral composition is analyzed.

[0039] Preferably, the metal cation concentration includes calcium ion concentration or magnesium ion concentration.

[0040] According to the present application, according to the hydrogen ion concentration and the metal cation concentration in the post-reaction solution, the change trend of the carbonate ion product of the reaction fluid is calculated, and the dissolution ability of the reaction fluid to the rock sample and the amount of carbonate precipitate generated are estimated; and / or

[0041] According to the results of the micro-morphology observation and the mineral composition analysis of the post-reaction rock sample, the evolution of the dissolution characteristics and the relationship between different reaction progress are summarized, and the evolution law of the reservoir internal reservoir space in the open environment is analyzed and predicted.

[0042] According to the present application, before the experiment starts, the sealing performance of the whole quantitative water-rock reaction experimental device is detected;

[0043] Then the carbon dioxide input device 20 is used to transport carbon dioxide gas into the reaction device 10; synchronously, the reaction fluid input device 30 is used to transport the solvent in the reaction fluid into the reaction device 10;

[0044] The chemical signal collection device 40 is used to collect the hydrogen ion concentration in the solvent, and then the step S1 is performed.

[0045] Compared with the prior art, the present application has at least the following advantages:

[0046] On the one hand, the quantitative water-rock reaction experimental device provided by the present application is first provided with a computer, which can automatically calculate the first target amount of reaction fluid required to carry out the water-rock reaction to the target reaction progress according to the determined target reaction progress before the experiment starts; further, the quantitative water-rock reaction experimental device provided by the present application is further provided with an automatic metering liquid feeding pipeline, which can automatically meter the reaction fluid pumped into the reaction device; the computer provided in the quantitative water-rock reaction experimental device can also obtain the amount of reaction fluid pumped into the reaction device from the automatic metering liquid feeding pipeline until the first target amount is reached, so as to realize the quantitative control of the water-rock reaction progress; based on the above structural design of the quantitative water-rock reaction experimental device provided by the present application, when the quantitative water-rock reaction experimental method provided by the present application is implemented, the water-rock reaction can be terminated at any reaction progress, and the kinetic parameters at the reaction progress can be obtained.

[0047] In another aspect, the present application also considers the influence of the reaction rate on the evolution of the dissolution characteristics and the different reaction progress, and specifically, the computer arranged in the quantitative water-rock reaction experimental device provided by the present application is further used to calculate and set a target pH value corresponding to the water-rock reaction at a target reaction rate according to the first-order kinetics of the rock sample and the reaction fluid, and the reaction rate of the water-rock reaction is stabilized at the target reaction rate by controlling the pH value of the reaction system at the target pH value during the water-rock reaction; for this purpose, the quantitative water-rock reaction experimental device provided by the present application is further provided with a chemical signal acquisition device, which can acquire the hydrogen ion concentration in the reaction system in the reaction device during the water-rock reaction, and the computer obtains the real-time hydrogen ion concentration in the reaction system from the chemical signal acquisition device and converts it into a real-time pH value, and when the real-time pH value exceeds the target pH value, the second target amount of the reaction fluid required for adjusting the real-time pH value to the target pH value is calculated, and the second target amount of the reaction fluid is pumped into the reaction system under the automatic metering of the automatic metering pipeline to adjust the pH value to the target pH value, so as to maintain the target reaction rate; based on the above structural design of the quantitative water-rock reaction experimental device provided by the present application, when the quantitative water-rock reaction experimental method provided by the present application is implemented, the pH value of the reaction system can be flexibly adjusted, and the water-rock reaction rate is stabilized at the target reaction rate.

[0048] In summary, through the structural design of the quantitative water-rock reaction experimental device and the quantitative water-rock reaction experimental method based on the quantitative water-rock reaction experimental device, the water-rock reaction at any reaction progress can be quantitatively carried out at an almost constant reaction rate, which is suitable for quantitatively and qualitatively simulating the process of the mutual reaction between the fluid and the surrounding rock from the deep formation to the surface formation, and can real-time monitor, record and store the mutual reaction process, solves the technical problem that the existing water-rock reaction device cannot quantitatively simulate the chemical kinetics process of different types of fluid and surrounding rock containing rock samples in different depths and different formations, and can also be applied to different lithological rock samples, and can study the process of the change of the carbonate reservoir physical property with temperature and pressure and the fluid dissolution surrounding rock-cemented pore in the continuous multi-stage tectonic uplift-subsidence process, monitor the degree of reservoir space expansion or filling under different temperature, pressure and flow conditions, and judge the occurrence trend of dissolution / precipitation, which has important scientific significance for monitoring the reconstruction degree of the carbonate reservoir by the fluid in different depths and identifying the formation mechanism of different environments. The quantitative water-rock reaction experimental device and experimental method provided by the present application can be used in the fields of reservoir formation, reservoir reconstruction, reservoir prediction research, and is suitable for popularization and use. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 The structural schematic diagram of the quantitative water-rock reaction experimental device provided by the embodiment of the present application.

[0050] The meanings of the reference numerals in the drawings are as follows:

[0051] 10 - reaction device, 20 - carbon dioxide input device, 30 - reaction fluid input device, 40 - chemical signal collection device, 50 - computer, 60 - separation device, 101 - liquid outlet pipeline, 102 - back pressure valve, 103 - third stop valve, 201 - gas inlet pipeline, 202 - first constant pressure and constant flow pumping device, 203 - first stop valve, 204 - first pressure vessel, 301 - automatic metering liquid inlet pipeline, 302 - second constant pressure and constant flow pumping device, 303 - second stop valve, 304 - second pressure vessel.

[0052] The drawings are not drawn according to the actual size and proportion. DETAILED DESCRIPTION

[0053] In order to make the technical solutions and advantages of the present application clearer, the exemplary embodiments of the present application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not an exhaustive enumeration of all embodiments. And in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0054] It is crucial to explore and develop deep-ultra-deep marine carbonate reservoirs to explicitly understand the interaction between carbonate reservoirs and formation fluids in surface-deep formation environment and the potential impact of these interactions on carbonate reservoirs. However, the interaction between carbonate reservoirs and formation fluids in surface-deep formation environment and the potential impact of these interactions on carbonate reservoirs have not been clearly understood, although there are some water-rock reaction devices and methods. However, most of these existing water-rock reaction devices and methods calculate reaction kinetics parameters such as reaction rate after the completion of the reaction, but cannot monitor the kinetics parameters at a certain moment or at a certain reaction progress during the reaction process, cannot quantitatively monitor the reaction progress, and cannot meet the technical needs of exploring the fluid-rock reaction process and reaction mechanism, which limits the in-depth study of the interaction between carbonate reservoirs and formation fluids in surface-deep formation environment and the potential impact of these interactions on carbonate reservoirs.

[0055] In view of the technical blank of the prior art in quantifying the water-rock reaction process, exploring the fluid-rock reaction process and reaction mechanism, the application provides a quantitative water-rock reaction experimental device and experimental method. The quantitative water-rock reaction experimental device provided by the application and the quantitative water-rock reaction experimental method provided by the application can quantitatively measure the water-rock reaction process, reflect the kinetic parameters of the reaction progress at the moment and the changes in the morphology of the water-rock reaction interface in real time, and quantitatively and qualitatively measure the interaction process of different types of reaction fluids and surrounding rocks in different depths and different formations, thereby providing an effective experimental device and experimental method for the genesis mechanism of deep-ultra-deep carbonate reservoirs and the prediction of deep-ultra-deep carbonate reservoirs.

[0056] The technical solutions of the application will be described in detail below with reference to the drawings.

[0057] As shown in Figure 1 The application provides a quantitative water-rock reaction experimental device, which comprises a reaction device 10 and a computer 50, and is connected with a carbon dioxide input device 20, a reaction fluid input device 30 and a chemical signal acquisition device 40, respectively. The reaction device 10 contains a basic fluid and a rock sample, and provides a place for water-rock reaction. The carbon dioxide input device 20 is used for controllably delivering carbon dioxide to the reaction device 10. The reaction fluid input device 30 is used for automatically and real-timely metering the delivery of reaction fluid to the reaction device 10. The chemical signal acquisition device 40 is used for real-time chemical signal acquisition. The computer 50 is used for acquiring real-time chemical signals and the delivery of reaction fluid, and controlling the carbon dioxide input device 20 and the reaction fluid input device 30, so as to quantitatively control the reaction progress and maintain the stability of the reaction rate.

[0058] In order to better simulate the interaction between the reaction fluid and the deep-ultra-deep marine carbonate reservoir, in one embodiment of the application, the rock sample is a carbonate rock sample, such as a calcium carbonate rock sample or a magnesium carbonate rock sample. The basic fluid is a sodium chloride-calcium chloride mixed solution. The reaction fluid is an acid liquid. Preferably, the salinity of the sodium chloride-calcium chloride mixed solution is the same as that of seawater. The acid liquid is dilute hydrochloric acid. Further preferably, the solvent in the reaction fluid is water.

[0059] In one embodiment of the present application, the carbon dioxide input device 20 comprises an inlet pipeline 201, and a first constant pressure and constant flow pumping device 202 and a first stop valve 203 arranged in sequence along the carbon dioxide conveying direction on the inlet pipeline 201. The inlet end of the inlet pipeline 201 is connected to a carbon dioxide gas source, and cooperates with the first constant pressure and constant flow pumping device 202 and the first stop valve 203 to controllably convey carbon dioxide gas into the reaction device 10. Further, the carbon dioxide input device 20 further comprises a first pressure container 204, which stores carbon dioxide gas as the carbon dioxide gas source. The form of the first pressure container 204 includes but is not limited to a top cap type.

[0060] In one embodiment of the present application, the reaction fluid input device 30 comprises an automatic metering liquid inlet pipeline 301, and a second constant pressure and constant flow pumping device 302 and a second stop valve 303 arranged in sequence along the reaction fluid conveying direction on the automatic metering liquid inlet pipeline 301; wherein the automatic metering liquid inlet pipeline 301 is used to automatically meter the amount of reaction fluid pumped into the reaction device 10 in real time. The liquid inlet end of the automatic metering liquid inlet pipeline 301 is connected to a reaction fluid source, and cooperates with the second constant pressure and constant flow pumping device 302 and the second stop valve 303 to automatically meter the reaction fluid conveyed into the reaction device 10 in real time. Further, the reaction fluid input device 30 further comprises a second pressure container 304, which contains the reaction fluid as the reaction fluid source. The form of the second pressure container 304 includes but is not limited to a top cap type.

[0061] In one embodiment of the present application, the automatic metering liquid inlet pipeline 301, the first constant pressure and constant flow pumping device 202, and the second constant pressure and constant flow pumping device 302 are respectively connected to the computer 50.

[0062] In one embodiment of the present application, the computer 50 is configured to calculate the first target amount of the reaction fluid required for quantitatively controlling the water-rock reaction to a target reaction progress, and to automatically acquire the amount of the reaction fluid pumped into the reaction device 10 in real time from the automatic metering liquid inlet pipeline 301; when the second constant pressure and flow pumping device 302 pumps the reaction fluid into the reaction device 10 to the first target amount, the computer 50 automatically controls the first constant pressure and flow pumping device 202 and the second constant pressure and flow pumping device 302 to be closed, stops pumping carbon dioxide and the reaction fluid into the reaction device 10, closes the first stop valve 203 and the second stop valve 303, and stops the reaction. In this way, the quantitative water-rock reaction experimental device provided by the embodiment of the present application can quantitatively control the water-rock reaction to any reaction progress, and can monitor the kinetic parameters at a certain time or a certain reaction progress in the reaction process, and study and compare the evolution of the dissolution characteristics of the rock sample under the reaction fluid and carbon dioxide gas at different reaction progress, thereby laying a foundation for in-depth research on the interaction between the carbonate rock reservoir and the formation fluid in the surface-deep formation environment and the potential influence of the interaction on the carbonate rock reservoir.

[0063] It should be noted that the method for calculating the amount of the reaction fluid required for the water-rock reaction to reach any reaction progress belongs to the prior art, and will not be described here.

[0064] In the water-rock reaction process, the reaction rate in the reaction process is kept substantially constant, which can basically eliminate the reaction rate as a variable, and is more conducive to the comparative study of the evolution of the dissolution characteristics of the rock sample under the reaction fluid and carbon dioxide gas at different reaction progress. Under the condition that the temperature is unchanged, the change of the reaction rate in the water-rock reaction process in the present application mainly reflects the change of the pH value of the entire reaction system, and therefore the real-time chemical signal acquisition at least includes real-time hydrogen ion concentration acquisition in the reaction system in the reaction device 10.

[0065] In one embodiment of the present application, the computer 50 is further configured to set a target pH value corresponding to a target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid. Taking a calcium carbonate rock sample as an example, after the target reaction rate is determined, the amount of substance of CaCO3 that should be reacted is calculated according to the target reaction progress; for example, it is known that 1 mol of CaCO3 corresponds to 2 mol of H+ 2+ , so when 10% of CaCO3 is reacted, 20% of H+ + should be reacted, and then the amount of substance of H+ + corresponding to the target pH value is calculated according to the amount of substance of H+ +The computer 50 is further configured to automatically obtain the real-time hydrogen ion concentration from the chemical signal acquisition device 40, and automatically convert the real-time hydrogen ion concentration into a real-time pH value, and compare the real-time pH value with the target pH value; in the case that the real-time pH value exceeds the target pH value, automatically calculate a second target amount of the reaction fluid required to adjust the real-time pH value to the target pH value; and automatically control the second constant pressure and flow pumping device 302 to pump the second target amount of the reaction fluid into the reaction device 10 through the automatic metering liquid inlet pipeline 301. During the process of pumping the reaction fluid into the reaction device 10, the automatic metering liquid inlet pipeline 301 automatically meters the pumped amount of the reaction fluid, and the chemical signal acquisition device 40 collects the real-time hydrogen ion concentration of the reaction system, until the computer 50 obtains the pumped amount of the reaction fluid from the automatic metering liquid inlet pipeline 301 to reach the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained from the chemical signal acquisition device 40 reaches the target pH value, so as to maintain the stability of the reaction rate. In this way, the reaction rate variable can be basically excluded, and further, for example, in actual application, the reaction rates in the processes of water-rock reaction experiments of different target reaction progress can be controlled at the same target reaction rate, and since the influence of the reaction rate variable is excluded, the comparative study of the evolution of the reaction fluid and the carbon dioxide gas to the rock sample dissolution characteristics under different reaction progress can be better performed.

[0066] In an embodiment of the present application, the computer 50 internally solidifies a program capable of realizing the above-mentioned functions, and the computer 50 realizes the above-mentioned functions of the computer 50 by executing the program.

[0067] In an embodiment of the present application, in order to facilitate sampling and characterization after the water-rock reaction is stopped at any reaction progress, the quantitative water-rock reaction experiment device further comprises a separation device 60, the separation device 60 and the reaction device 10 are connected through a liquid outlet pipeline 101, and are used to collect the post-reaction solution and the post-reaction rock sample from the post-reaction fluid to perform subsequent analysis and testing; a back pressure valve 102 and a third shut-off valve 103 are further arranged on the liquid outlet pipeline 101, and are respectively arranged near the inlet and the outlet of the separation device 60. The arrangement of the back pressure valve 102 can maintain the pressure in the reaction device 10 at a specified pressure (for example, atmospheric pressure) during the water-rock reaction, so as to exclude the influence of the pressure factor on the comparative study of the evolution of the reaction fluid and the carbon dioxide gas to the rock sample dissolution characteristics under different reaction progress.

[0068] In one embodiment of the present application, the reaction device 10 is a reactor made of any one of Hastelloy, PTFE, PEEK and ceramic. The material of the reactor can be selected according to the specified pressure and temperature, and the material should be able to withstand the specified pressure and temperature. Further, the reactor is also provided with a jacket for adjusting the temperature of the reaction system to the specified temperature.

[0069] In one embodiment of the present application, the quantitative water-rock reaction experimental device further comprises a preheating device (not shown in the figure). Further, the preheating device can be an oven that wraps the entire quantitative water-rock reaction experimental device. Before the experiment, the oven is used to preheat the entire quantitative water-rock reaction experimental device, so that the carbon dioxide gas, the reaction fluid, the base fluid and the rock sample involved in the water-rock reaction process can more easily reach the specified temperature.

[0070] In one embodiment of the present application, the preheating device can also be a heating jacket (for example, a commonly marketed heating jacket with an internal heating component made of glass fiber) that wraps the gas inlet pipeline 201, the automatic metering liquid inlet pipeline 301 and the reaction device 10 respectively, so as to preheat the carbon dioxide, the reaction fluid input into the reaction device 10, and the base fluid and the rock sample in the reaction device 10.

[0071] The embodiment of the present application also provides a quantitative water-rock reaction experimental method, which is realized according to the quantitative water-rock reaction experimental device described in the above embodiments of the present application, and comprises the following steps:

[0072] S1. The base fluid and the rock sample are added into the reaction device 10, the carbon dioxide is controllably delivered into the reaction device 10 through the carbon dioxide input device 20, and the reaction fluid is automatically metered and delivered into the reaction device 10 in real time through the reaction fluid input device 30, so as to perform the water-rock reaction; S2. In the water-rock reaction process, the reaction device 10 is subjected to real-time chemical signal collection through the chemical signal collection device 40, and the reaction rate is maintained stable under the control of the computer 50 in cooperation with the reaction fluid input device 30; S3. The computer 50 is used to acquire the real-time chemical signal and the delivery amount of the reaction fluid, control the delivery amounts of the carbon dioxide and the reaction fluid into the reaction device 10 through the carbon dioxide input device 20 and the reaction fluid input device 30, and quantitatively control the reaction progress; when the water-rock reaction reaches the target reaction progress, the reaction is stopped, and sampling is performed for subsequent analysis and testing.

[0073] In one embodiment of the present application, before the experiment starts, the sealing performance of the whole quantitative water-rock reaction experiment device is detected; then the carbon dioxide gas is transported into the reaction device 10 through the carbon dioxide input device 20; synchronously, the solvent (such as water) in the reaction fluid is transported into the reaction device 10 through the reaction fluid input device 30; the hydrogen ion concentration in the solvent is collected through the chemical signal collection device 40, and then the step S1 is performed. The specific operation method of detecting the sealing performance of the device belongs to the prior art, and will not be described here.

[0074] In one embodiment of the present application, before the experiment starts, the first target amount of the reaction fluid required for quantitatively controlling the water-rock reaction to the target reaction progress is calculated by the computer 50; and / or the target pH value corresponding to the target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid is set, and then the step S1 is performed. The calculation of the amount of the reaction fluid required for quantitatively controlling the water-rock reaction to the target reaction progress and the target pH value corresponding to the target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid can be performed before, after or simultaneously with the steps of performing the sealing performance detection and collecting the hydrogen ion concentration in the solvent.

[0075] Based on the quantitative water-rock reaction experiment device provided in the above embodiments of the present application, the quantitative water-rock reaction experiment method provided in the embodiments of the present application can quantitatively investigate the kinetic parameters of the water-rock reaction under any reaction progress, and study and compare the evolution of the dissolution characteristics of the rock sample under different reaction progress.

[0076] In one embodiment of the present application, in step S1, the back pressure valve 102, the third stop valve 103 and the first stop valve 203 are opened, the first constant pressure and constant flow pumping device 202 is started, the carbon dioxide is pumped into the reaction device 10 through the gas inlet pipeline 201; synchronously, the second stop valve 303 is opened, the second constant pressure and constant flow pumping device 302 is started, and the reaction fluid is pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301; the automatic metering liquid inlet pipeline 301 automatically meters the pumping amount of the reaction fluid.

[0077] In one embodiment of the present application, in step S2, the real-time hydrogen ion concentration of the reaction system in the reaction device 10 is collected by the chemical signal collection device 40; the real-time hydrogen ion concentration is obtained from the chemical signal collection device 40 by the computer 50, and the real-time pH value is automatically converted; the real-time pH value is automatically compared with the target pH value, and when the real-time pH value exceeds the target pH value, the second target amount of the reaction fluid required for adjusting the pH to the target pH value is automatically calculated; under the automatic control of the computer 50, the second target amount of the reaction fluid is pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301 by the second constant pressure and constant flow pumping device 302. During the pumping of the reaction fluid, the pumped amount of the reaction fluid is automatically metered in real time by the automatic metering liquid inlet pipeline 301, and the real-time hydrogen ion concentration in the reaction system is collected by the chemical signal collection device 40; until the pumped amount of the reaction fluid obtained from the automatic metering liquid inlet pipeline 301 by the computer 50 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained from the chemical signal collection device 40 reaches the target pH value, the reaction rate of the water-rock reaction is maintained at the target reaction rate.

[0078] In one embodiment of the present application, in step S3, the amount of the reaction fluid pumped into the reaction device 10 is obtained from the automatic metering liquid inlet pipeline 301 by the computer 50, and when the first target amount is reached, it represents that the water-rock reaction reaches the target reaction progress; the computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to close, stops pumping carbon dioxide and the reaction fluid into the reaction device 10, closes the first stop valve 203 and the second stop valve 303, and stops the reaction.

[0079] In one embodiment of the present application, after the water-rock reaction reaches the target reaction progress and the reaction is stopped, the post-reaction fluid is transported to the separation device 60 through the liquid outlet pipeline 101 for solid-liquid separation, and the post-reaction solution and the post-reaction rock sample are collected. Then, the post-reaction solution and the post-reaction rock sample are respectively analyzed and tested.

[0080] In one embodiment of the present application, in step S3, the subsequent analysis and testing includes detecting the hydrogen ion concentration in the post-reaction solution and the metal cation concentration contained in the rock sample; and / or

[0081] The surface morphology of the post-reaction rock sample is observed and the mineral composition is analyzed.

[0082] Preferably, the metal cation concentration includes the calcium ion concentration or the magnesium ion concentration.

[0083] In one embodiment of the present application, the change trend of the carbonate ion product of the reaction fluid is calculated according to the hydrogen ion concentration and the metal cation concentration in the solution after the reaction, the dissolution capacity of the reaction fluid to the rock sample and the amount of carbonate precipitate generated are estimated, the evolution of the dissolution characteristics and the relationship of different reaction progress are summarized according to the results of the micro-morphology observation and the mineral composition analysis of the rock sample after the reaction, and then the evolution law of the internal reservoir space in the reservoir in the open environment is analyzed and predicted.

[0084] The quantitative water-rock reaction experimental method provided by the present application will be introduced in detail in the following three embodiments taking the reaction progress of 10%, 20% and 50% as examples in combination with the quantitative water-rock reaction experimental device shown in the drawings. Figure 1

[0085] The part of raw material information used in the following embodiments is as follows:

[0086] Calcium chloride solid: analytical pure;

[0087] Sodium chloride solid: analytical pure;

[0088] Dilute hydrochloric acid: the total mass of the dilute hydrochloric acid is 100%, and the mass of HCl accounts for 5wt%.

[0089] The part of device information used in the following embodiments is as follows:

[0090] Reaction device: reaction kettle with jacket made of hastelloy;

[0091] First and second constant pressure and flow pumping devices: constant pressure and flow pumps;

[0092] Chemical signal collection device: ion sensor;

[0093] Automatic metering liquid inlet pipeline: pipeline with a small sample pump (not shown in the figure) capable of automatically metering the liquid inlet amount;

[0094] ​Computer: solidified with the program capable of realizing the following functions, the functions at least include calculating the first target amount of reaction fluid required to quantitatively control the water-rock reaction to the target reaction progress, and capable of automatically acquiring the amount of reaction fluid pumped into the reaction device 10 from the automatic metering liquid inlet pipeline 301 in real time; according to the first order kinetics between the rock sample and the reaction fluid, set the target pH value corresponding to the target reaction rate; automatically acquire real-time hydrogen ion concentration from the chemical signal acquisition device 40, and automatically convert it into real-time pH value, and compare it with the target pH value; automatically calculate the second target amount of reaction fluid required to adjust the real-time pH value to the target pH value; control the opening and closing of the first constant pressure constant flow pumping device 202, the second constant pressure constant flow pumping device 302, the first stop valve 203 and the second stop valve 303, control the quantitative water-rock reaction to the target reaction progress and maintain the stability of the reaction rate.

[0095] Example 1

[0096] This embodiment uses the quantitative water-rock reaction experimental device as shown in Figure 1 The temperature and pressure are specified as normal temperature and pressure, the quantitative water-rock reaction experimental method provided by the present application is implemented, the water-rock reaction is quantitatively carried out to 10% of the reaction progress, the reaction is stopped, and then sampling is carried out for analysis test.

[0097] In this embodiment, water is used as the solvent, sodium chloride and calcium chloride solids are dissolved in water to obtain a sodium chloride-calcium chloride mixed solution with the same salinity as seawater, which is the base fluid.

[0098] In this embodiment, the solvent-water of the above-mentioned base fluid is used as the blank fluid.

[0099] In this embodiment, dilute hydrochloric acid is used as the reaction fluid.

[0100] The specific steps are as follows.

[0101] S1. Add the base fluid and the rock sample to the reaction device 10, controllably transport carbon dioxide into the reaction device 10 through the carbon dioxide input device 20, and automatically meter the reaction fluid into the reaction device 10 through the reaction fluid input device 30 in real time, and carry out the water-rock reaction.

[0102] Specifically,

[0103] S1-1. Prepare the base fluid and prepare the rock sample;

[0104] Add sodium chloride solids and calcium chloride solids to water, stir until the two solids are completely dissolved, to obtain a sodium chloride-calcium chloride mixed solution with the same salinity as seawater, which is used as the base fluid of this embodiment;

[0105] The limestone sample collected (belonging to the calcium carbonate type) is crushed to obtain particles with a diameter of 2-4 mm, which are used as the rock sample in this example.

[0106] S1-2. Perform sealing performance test on the quantitative water-rock reaction experimental device and determine the background concentration of hydrogen ions in the blank fluid.

[0107] According to the formula: Figure 1 Connect the pipelines between the devices, open the first stop valve 203, the second stop valve 303, and the third stop valve 103, then pour water into the second pressure vessel 304, and store carbon dioxide gas in the first pressure vessel 204. Use the first constant pressure and constant flow pumping device 202 to pump the carbon dioxide gas into the reaction device 10 through the gas inlet pipeline 201, and at the same time, use the second constant pressure and constant flow pumping device 302 to pump water into the reaction device 10 through the automatic metering liquid inlet pipeline 301, to test the sealing performance of the entire quantitative water-rock reaction experimental device. At the same time, the chemical signal acquisition device 40 is used to collect the hydrogen ion concentration in the water into which the carbon dioxide gas is introduced in the reaction device 10. Then, close the first stop valve 203, the second stop valve 303, and the third stop valve 103.

[0108] S1-3. Calculate the amount of reaction fluid required to quantitatively control the water-rock reaction to the target reaction progress, and set the target pH value corresponding to the target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid.

[0109] Through the program solidified in the computer 50, the first target amount of dilute hydrochloric acid required to quantitatively control the water-rock reaction to 10% of the reaction progress is calculated, and the reaction rate is set to 1×10 -5 mol·cm -3 ·sec -1 , and the corresponding target pH value is 5.1. The reaction time is calculated according to the 10% reaction progress and the determined reaction rate.

[0110] S1-4. Perform water-rock reaction of carbon dioxide gas, reaction fluid, and rock sample in the base fluid.

[0111] Take 1 g of the rock sample prepared in step S1-1 and add it to the reaction device 10, and inject 100 mL of the sodium chloride-calcium chloride mixed solution prepared in step S1-1 into the reaction device 10; replace the water in the second pressure container 304 with dilute hydrochloric acid, open the first stop valve 203, the second stop valve 303, the back pressure valve 102, and the third stop valve 103, and continuously pump the carbon dioxide gas in the first pressure container 204 into the reaction device 10 at a constant flow rate through the first constant pressure and flow pumping device 202; synchronously, continuously pump the dilute hydrochloric acid in the second pressure container 304 into the reaction device 10 at a constant flow rate through the second constant pressure and flow pumping device 302, and start timing the reaction, and the automatic metering of the amount of dilute hydrochloric acid pumped through the automatic metering liquid inlet pipeline 301 is performed.

[0112] S2. During the water-rock reaction, the chemical signal acquisition device 40 acquires real-time chemical signals from the reaction device 10, and cooperates with the reaction fluid input device 30 to maintain the stability of the reaction rate under the control of the computer 50.

[0113] Specifically,

[0114] S2-1. During the water-rock reaction, the chemical signal acquisition device 40 acquires real-time hydrogen ion concentration in the reaction device 10, and the computer 50 obtains the real-time hydrogen ion concentration from the chemical signal acquisition device 40 and automatically converts it to obtain the real-time pH value; the real-time pH value is automatically compared with the target pH value set in advance;

[0115] S2-2. When the real-time pH value exceeds the target pH value, the computer 50 automatically calculates the second target amount of dilute hydrochloric acid required to adjust the pH to the target pH value, and under the automatic control of the computer 50, the second constant pressure and flow pumping device 302 pumps the second target amount of dilute hydrochloric acid required to adjust the pH to the target pH value into the reaction device 10 through the automatic metering liquid inlet pipeline 301. During the pumping of the dilute hydrochloric acid, the automatic metering of the amount of dilute hydrochloric acid pumped through the automatic metering liquid inlet pipeline 301 is performed in real time, and the chemical signal acquisition device 40 acquires the real-time hydrogen ion concentration in the reaction system; until the computer 50 obtains the pumping amount of dilute hydrochloric acid from the automatic metering liquid inlet pipeline 301 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained from the chemical signal acquisition device 40 reaches the target pH value, the reaction rate of the water-rock reaction is maintained at the target reaction rate.

[0116] S3. The computer 50 is used to obtain the real-time chemical signals and the delivery amount of the reaction fluid, and control the carbon dioxide input device 20 and the reaction fluid input device 30 to deliver carbon dioxide and the reaction fluid to the reaction device 10 respectively, so as to quantitatively control the reaction progress. When the water-rock reaction reaches 10% of the reaction progress, the reaction is stopped, and the sample is taken for subsequent analysis and testing.

[0117] Specifically,

[0118] S3-1. The computer 50 is used to obtain the amount of dilute hydrochloric acid pumped to the reaction device 10 from the automatic metering liquid inlet pipeline 301, and when the amount of dilute hydrochloric acid pumped to the reaction device 10 reaches the first target amount required to control the water-rock reaction to 10% of the reaction progress, it represents that the water-rock reaction reaches 10% of the reaction progress. The computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to be closed, stops pumping carbon dioxide and dilute hydrochloric acid into the reaction device 10, and closes the first stop valve 203 and the second stop valve 303, thereby stopping the reaction.

[0119] S3-2. The post-reaction fluid is delivered to the separation device 60 through the liquid outlet pipeline 101 for solid-liquid separation, so as to collect the post-reaction solution and the post-reaction rock sample.

[0120] S3-3. The post-reaction solution and the post-reaction rock sample are subjected to subsequent analysis and testing.

[0121] First, the post-reaction solution and the post-reaction rock sample are characterized: the hydrogen ion concentration and the calcium ion concentration in the post-reaction solution are tested, and then the pH value of the post-reaction solution is calculated; after the post-reaction rock sample is dried, the surface morphology thereof is observed by means of a scanning electron microscope, and the mineral composition thereof is tested by means of XRD, and is compared with the initial mineral composition of the rock sample before the water-rock reaction, so as to obtain the mineral composition change of the post-reaction rock sample.

[0122] Then, the above characterization results are subjected to data processing: based on the obtained pH value of the post-reaction solution and the calcium ion concentration contained therein, the calcium carbonate ion product change trend of dilute hydrochloric acid is calculated, and the dissolution ability of dilute hydrochloric acid to the rock sample is estimated; according to the surface morphology of the post-reaction rock sample observed by means of the scanning electron microscope, the morphological differences of crystals / grains are sorted out, and the mineral composition change of the post-reaction rock sample tested by means of XRD is combined, so as to analyze the morphological change characteristics of the original pores, holes and cracks of the rock sample after the water-rock reaction, summarize the relationship between the dissolution characteristics evolution and 10% of the reaction progress, and then analyze and predict the evolution law of the internal reservoir space in the open environment.

[0123] Embodiment 2

[0124] In this embodiment, as Figure 1The quantitative water-rock reaction experimental device shown is at normal temperature and pressure, and the quantitative water-rock reaction is carried out to 20% of the reaction progress, the reaction is stopped, and then sampling is carried out for analysis and testing.

[0125] In this embodiment, water is used as the solvent, sodium chloride and calcium chloride solids are dissolved in water to obtain a sodium chloride-calcium chloride mixed solution with the same salinity as seawater, which is the base fluid.

[0126] In this embodiment, the solvent-water of the above base fluid is used as the blank fluid.

[0127] In this embodiment, dilute hydrochloric acid is used as the reaction fluid.

[0128] The specific steps are as follows.

[0129] S1. Add the base fluid and rock sample to the reaction device 10, controllably transport carbon dioxide into the reaction device 10 through the carbon dioxide input device 20, and automatically meter the reaction fluid into the reaction device 10 in real time through the reaction fluid input device 30 to carry out the water-rock reaction.

[0130] Specifically,

[0131] S1-1. Prepare the base fluid and prepare the rock sample;

[0132] Add sodium chloride solids and calcium chloride solids to water, stir until the two solids are completely dissolved, and obtain a sodium chloride-calcium chloride mixed solution with the same salinity as seawater as the base fluid of this embodiment;

[0133] The collected limestone sample (belonging to calcium carbonate rock sample) is crushed to obtain particles with a diameter of 2-4 mm as the rock sample of this embodiment.

[0134] S1-2. Test the sealing performance of the quantitative water-rock reaction experimental device and determine the background concentration of hydrogen ions in the blank fluid;

[0135] According to Figure 1The pipes connecting the devices are connected, the first stop valve 203, the second stop valve 303 and the third stop valve 103 are opened, then water is filled in the second pressure container 304, and carbon dioxide gas is stored in the first pressure container 204, the carbon dioxide gas is pumped into the reaction device 10 through the gas inlet pipeline 201 by using the first constant pressure and constant flow pumping device 202, at the same time, the water is pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301 by using the second constant pressure and constant flow pumping device 302, and the sealing performance of the whole quantitative water-rock reaction experimental device is tested; at the same time, the chemical signal acquisition device 40 is used to acquire the hydrogen ion concentration in the water into which the carbon dioxide gas is introduced in the reaction device 10; then the first stop valve 203, the second stop valve 303 and the third stop valve 103 are closed.

[0136] S1-3. Calculation of the amount of reaction fluid required for quantitative control of the water-rock reaction at a target reaction progress, and setting of a target pH value corresponding to a target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid;

[0137] By executing the program solidified in the computer 50, the first target amount of dilute hydrochloric acid required for quantitative control of the water-rock reaction at a reaction progress of 20% is calculated, and the reaction rate is set to 1×10 -5 mol·cm -3 ·sec -1 , and the corresponding target pH value is 5.2, and the reaction time is calculated according to the reaction progress of 20% and the determined reaction rate.

[0138] S1-4. Water-rock reaction of carbon dioxide gas, reaction fluid and rock sample in the base fluid;

[0139] 1g of the rock sample prepared in step S1-1 is weighed and added to the reaction device 10, and 100mL of the sodium chloride-calcium chloride mixed solution prepared in step S1-1 is injected into the reaction device 10; the water in the second pressure container 304 is replaced with dilute hydrochloric acid, the first stop valve 203, the second stop valve 303, the back pressure valve 102 and the third stop valve 103 are opened, and the carbon dioxide gas in the first pressure container 204 is continuously pumped into the reaction device 10 at a constant flow rate through the gas inlet pipeline 201 by using the first constant pressure and constant flow pumping device 202; at the same time, the dilute hydrochloric acid in the second pressure container 304 is continuously pumped into the reaction device 10 at a constant flow rate through the automatic metering liquid inlet pipeline 301 by using the second constant pressure and constant flow pumping device 302, the reaction is timed, and the automatic metering liquid inlet pipeline 301 automatically meters the pumping amount of the dilute hydrochloric acid.

[0140] S2. In the process of the water-rock reaction, the real-time chemical signal of the reaction device 10 is collected by the chemical signal collection device 40, and the reaction rate is maintained stable under the control of the computer 50 in cooperation with the reaction fluid input device 30.

[0141] Specifically,

[0142] S2-1. In the process of the water-rock reaction, the real-time hydrogen ion concentration in the reaction device 10 is collected by the chemical signal collection device 40, and the real-time pH value is obtained by the computer 50 from the chemical signal collection device 40 and automatically converted; the real-time pH value is automatically compared with the pre-set target pH value;

[0143] S2-2. When the real-time pH value exceeds the target pH value, the computer 50 automatically calculates the second target amount of dilute hydrochloric acid required to adjust the pH to the target pH value, and under the automatic control of the computer 50, the second constant pressure and constant flow pumping device 302 pumps the second target amount of dilute hydrochloric acid required to adjust the pH to the target pH value into the reaction device 10 through the automatic metering liquid inlet pipeline 301. During the pumping of the dilute hydrochloric acid, the pumping amount of the dilute hydrochloric acid is automatically metered in real time by the automatic metering liquid inlet pipeline 301, and the real-time hydrogen ion concentration in the reaction system is collected by the chemical signal collection device 40; until the computer 50 obtains the pumping amount of the dilute hydrochloric acid from the automatic metering liquid inlet pipeline 301 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained from the chemical signal collection device 40 reaches the target pH value, the reaction rate of the water-rock reaction is maintained at the target reaction rate.

[0144] S3. The computer 50 obtains the real-time chemical signal and the delivery amount of the reaction fluid, controls the carbon dioxide input device 20 and the reaction fluid input device 30 to deliver the amount of carbon dioxide and the amount of reaction fluid to the reaction device 10 respectively, and quantitatively controls the reaction progress; when the water-rock reaction reaches 20% of the reaction progress, the reaction is stopped, and sampling is performed for subsequent analysis and testing.

[0145] Specifically,

[0146] S3-1. The computer 50 obtains the amount of dilute hydrochloric acid pumped into the reaction device 10 from the automatic metering liquid inlet pipeline 301, and when the amount of dilute hydrochloric acid pumped into the reaction device 10 reaches the first target amount required to control the water-rock reaction at 20% of the reaction progress, it represents that the water-rock reaction reaches 20% of the reaction progress; the computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to close, stops pumping carbon dioxide and dilute hydrochloric acid into the reaction device 10, and closes the first stop valve 203 and the second stop valve 303 to stop the reaction;

[0147] S3-2. The post-reaction fluid is transported to the separation device 60 through the effluent pipeline 101 for solid-liquid separation, and the post-reaction solution and the post-reaction rock sample are collected;

[0148] S3-3. The post-reaction solution and the post-reaction rock sample are subjected to subsequent analysis and testing;

[0149] First, the post-reaction solution and the post-reaction rock sample are characterized: the hydrogen ion concentration and the calcium ion concentration in the post-reaction solution are tested, and then the pH value of the post-reaction solution is calculated; after the post-reaction rock sample is dried, its surface morphology is observed by scanning electron microscopy, and its mineral composition is tested by XRD, and compared with the initial mineral composition of the rock sample before the water-rock reaction, to obtain the mineral composition change of the post-reaction rock sample;

[0150] Then, the above characterization results are processed: based on the obtained pH value of the post-reaction solution and the calcium ion concentration contained therein, the change trend of the dilute hydrochloric acid calcium carbonate ion product is calculated, and the dissolution ability of dilute hydrochloric acid to the rock sample is estimated; according to the surface morphology of the post-reaction rock sample observed by scanning electron microscopy, the morphological differences of crystals / particles are sorted out, combined with the mineral composition change of the post-reaction rock sample tested by XRD, the morphological change characteristics of the original pores, holes and cracks of the rock sample after the water-rock reaction are analyzed, the relationship between the evolution of dissolution characteristics and the 20% reaction progress is summarized, and then the evolution law of the internal reservoir space in the open environment is analyzed and predicted.

[0151] Example 3

[0152] This example uses a quantitative water-rock reaction experimental device as shown in Figure 1 The temperature and pressure are specified as normal temperature and pressure, the quantitative water-rock reaction experimental method provided by the present application is implemented, the water-rock reaction is quantitatively carried out to 50% of the reaction progress, the reaction is stopped, and then sampling is carried out for analysis and testing.

[0153] In this example, water is used as the solvent, sodium chloride and calcium chloride solids are dissolved in water to obtain a sodium chloride-calcium chloride mixed solution with the same salinity as seawater, which is the base fluid.

[0154] In this example, the solvent-water of the above base fluid is used as the blank fluid.

[0155] In this example, dilute hydrochloric acid is used as the reaction fluid.

[0156] The specific steps are as follows.

[0157] S1. Adding the base fluid and the rock sample into the reaction device 10, controllably feeding carbon dioxide into the reaction device 10 through the carbon dioxide input device 20, automatically metering the reaction fluid into the reaction device 10 in real time through the reaction fluid input device 30, and performing the water-rock reaction.

[0158] Specifically,

[0159] S1-1. Preparing the base fluid and the rock sample;

[0160] Sodium chloride solid and calcium chloride solid were added into water and stirred until the two solids were completely dissolved, obtaining a sodium chloride-calcium chloride mixed solution with the same salinity as seawater as the base fluid of the present embodiment.

[0161] The collected limestone sample (belonging to the calcium carbonate type of rock sample) was crushed to obtain particles with a diameter of 2-4 mm as the rock sample of the present embodiment.

[0162] S1-2. Sealing performance test of the quantitative water-rock reaction experimental device and determination of hydrogen ion background concentration in the blank fluid;

[0163] According to the sealing performance test of the quantitative water-rock reaction experimental device and the determination of hydrogen ion background concentration in the blank fluid, Figure 1 The pipelines between the devices were connected, the first stop valve 203, the second stop valve 303, and the third stop valve 103 were opened, then water was placed in the second pressure vessel 304, and carbon dioxide gas was stored in the first pressure vessel 204. The carbon dioxide gas was pumped into the reaction device 10 through the gas inlet pipeline 201 using the first constant pressure and constant flow pumping device 202, and at the same time, the water was pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301 using the second constant pressure and constant flow pumping device 302, to test the sealing performance of the entire quantitative water-rock reaction experimental device. At the same time, the chemical signal acquisition device 40 was used to collect the hydrogen ion concentration in the water into which the carbon dioxide gas was introduced in the reaction device 10. Then the first stop valve 203, the second stop valve 303, and the third stop valve 103 were closed.

[0164] S1-3. Calculation of the amount of reaction fluid required to quantitatively control the water-rock reaction to the target reaction progress, and setting the target pH value corresponding to the target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid;

[0165] The computer 50 executes the program solidified therein to calculate the first target amount of dilute hydrochloric acid required to quantitatively control the water-rock reaction to 50% of the reaction progress, and set the reaction rate to 1×10 -5 mol·cm -3 ·sec -1 , corresponding to a target pH value of 5.4, and the reaction duration is calculated according to the 50% reaction progress and the determined reaction rate.

[0166] S1-4. In the base fluid, water-rock reaction of carbon dioxide gas, reaction fluid and rock sample is carried out;

[0167] 1 g of the rock sample prepared in step S1-1 is weighed and added into the reaction device 10, and 100 mL of the sodium chloride-calcium chloride mixed solution prepared in step S1-1 is injected into the reaction device 10; the water in the second pressure container 304 is replaced with dilute hydrochloric acid, the first stop valve 203, the second stop valve 303, the back pressure valve 102 and the third stop valve 103 are opened, and the carbon dioxide gas in the first pressure container 204 is continuously pumped into the reaction device 10 at a constant flow rate through the gas inlet pipeline 201 by the first constant pressure and constant flow pumping device 202; synchronously, the dilute hydrochloric acid in the second pressure container 304 is continuously pumped into the reaction device 10 at a constant flow rate through the automatic metering liquid inlet pipeline 301 by the second constant pressure and constant flow pumping device 302, and the reaction is timed, and the pumping amount of the dilute hydrochloric acid by the automatic metering liquid inlet pipeline 301 is automatically metered.

[0168] S2. During the water-rock reaction, the reaction device 10 is subjected to real-time chemical signal collection by the chemical signal collection device 40, and the reaction rate is maintained stable under the control of the computer 50 in cooperation with the reaction fluid input device 30.

[0169] Specifically,

[0170] S2-1. During the water-rock reaction, the real-time hydrogen ion concentration in the reaction device 10 is collected by the chemical signal collection device 40, the real-time hydrogen ion concentration is obtained from the chemical signal collection device 40 by the computer 50, and the real-time pH value is automatically converted; the real-time pH value is automatically compared with the target pH value set in advance;

[0171] S2-2. When the real-time pH value exceeds the target pH value, the computer 50 automatically calculates the second target amount of dilute hydrochloric acid required for adjusting the pH to the target pH value, and under the automatic control of the computer 50, the second target amount of dilute hydrochloric acid required for adjusting the pH to the target pH value is pumped into the reaction device 10 through the automatic metering liquid inlet pipeline 301 by the second constant pressure and constant flow pumping device 302. During the pumping of the dilute hydrochloric acid, the pumping amount of the dilute hydrochloric acid is automatically metered in real time by the automatic metering liquid inlet pipeline 301, and the real-time hydrogen ion concentration in the reaction system is collected by the chemical signal collection device 40; until the pumping amount of the dilute hydrochloric acid obtained from the automatic metering liquid inlet pipeline 301 by the computer 50 reaches the second target amount, and the real-time pH value converted from the real-time hydrogen ion concentration obtained from the chemical signal collection device 40 reaches the target pH value, the reaction rate of the water-rock reaction is maintained at the target reaction rate.

[0172] S3. The computer 50 is used to obtain the real-time chemical signals and the delivery amount of the reaction fluid, and control the carbon dioxide input device 20 and the reaction fluid input device 30 to deliver the carbon dioxide and the reaction fluid to the reaction device 10, respectively, so as to quantitatively control the reaction progress; when the water-rock reaction reaches 50% of the reaction progress, the reaction is stopped, and the sample is taken for subsequent analysis and testing.

[0173] Specifically,

[0174] S3-1. The computer 50 is used to obtain the amount of the dilute hydrochloric acid pumped to the reaction device 10 from the automatic metering liquid inlet pipeline 301, and when the amount of the dilute hydrochloric acid pumped to the reaction device 10 reaches the first target amount of the dilute hydrochloric acid required for controlling the water-rock reaction at 50% of the reaction progress, it is indicated that the water-rock reaction reaches 50% of the reaction progress; the computer 50 automatically controls the first constant pressure and constant flow pumping device 202 and the second constant pressure and constant flow pumping device 302 to be closed, stops pumping the carbon dioxide and the dilute hydrochloric acid to the reaction device 10, and closes the first stop valve 203 and the second stop valve 303 to stop the reaction;

[0175] S3-2. The post-reaction fluid is delivered to the separation device 60 through the liquid outlet pipeline 101 for solid-liquid separation, so as to collect the post-reaction solution and the post-reaction rock sample;

[0176] S3-3. The post-reaction solution and the post-reaction rock sample are subjected to subsequent analysis and testing;

[0177] Firstly, the post-reaction solution and the post-reaction rock sample are characterized: the hydrogen ion concentration and the calcium ion concentration in the post-reaction solution are tested, and then the pH value of the post-reaction solution is calculated; after the post-reaction rock sample is dried, the surface morphology thereof is observed by means of a scanning electron microscope, and the mineral composition thereof is tested by means of XRD, and is compared with the initial mineral composition of the rock sample before the water-rock reaction, so as to obtain the change of the mineral composition of the post-reaction rock sample;

[0178] Then, the above characterization results are subjected to data processing: based on the pH value of the post-reaction solution and the calcium ion concentration contained therein, the change trend of the calcium carbonate ion product of the dilute hydrochloric acid is calculated, and the dissolution ability of the dilute hydrochloric acid to the rock sample is estimated; according to the surface morphology of the post-reaction rock sample observed by means of the scanning electron microscope, the morphological differences of the crystals / grains are sorted out, the change of the original pores, holes and cracks of the rock sample after the water-rock reaction is analyzed in combination with the change of the mineral composition of the post-reaction rock sample tested by means of the XRD, the relationship between the evolution of the dissolution characteristics and 50% of the reaction progress is summarized, and then the evolution law of the internal reservoir space in the open environment is analyzed and predicted.

[0179] Based on the characterization results obtained from Examples 1 to 3, we can further summarize the relationship between the evolution of dissolution characteristics and different reaction progresses (e.g., 10%, 20%, and 50%), so as to better analyze and predict the evolution of reservoir space within the reservoir under open conditions.

[0180] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0181] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0182] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0183] Certain terms are used throughout this application to refer to specific system components. As those skilled in the art will recognize, the same components may often be referred to by different names, and therefore this application is not intended to distinguish components that differ only in name and not in function. The terms "an embodiment" or "embodiment" used in the specification mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "embodiment" appearing throughout the specification does not necessarily refer to the same embodiment.

[0184] Embodiments of the present application are presented by way of example and description, and are not intended to be exhaustive or to limit the application to the form disclosed. Many modifications and variations will be apparent to those skilled in the art upon reading this disclosure. Embodiments are chosen and described in order to best explain principles of the application and its practical application to thereby enable others skilled in the art to best utilize the application, various embodiments with various modifications as are suited to the particular use contemplated.

[0185] While the preferred embodiments of the application have been described, additional variations and modifications can be made to the embodiments by those skilled in the art once they have the benefit of the basic inventive concepts. Therefore, the appended claims are intended to encompass all such variations and / or modifications of the embodiments as fall within the scope of the application.

Claims

1. A quantitative water-rock reaction experimental apparatus, characterized in that, It includes a reaction apparatus (10) and a computer (50); and a carbon dioxide input device (20), a reaction fluid input device (30), and a chemical signal acquisition device (40) respectively connected to the reaction apparatus (10) and the computer (50); wherein, The reaction device (10) holds the basic fluid and rock sample, providing a site for the water-rock reaction; The carbon dioxide input device (20) is used to controllably supply carbon dioxide to the reaction device (10); The reaction fluid input device (30) is used to automatically and in real time supply reaction fluid to the reaction device (10); The chemical signal acquisition device (40) is used for real-time chemical signal acquisition; The computer (50) is used to acquire real-time chemical signals and the amount of reaction fluid delivered, and to control the carbon dioxide input device (20) and the reaction fluid input device (30) to achieve quantitative control of the reaction progress and maintain the stability of the reaction rate.

2. The quantitative water-rock reaction experimental apparatus according to claim 1, characterized in that, The carbon dioxide input device (20) includes an intake pipeline (201), and a first constant pressure and constant flow pumping device (202) and a first shut-off valve (203) sequentially arranged on the intake pipeline (201) along the carbon dioxide delivery direction; and / or The reaction fluid input device (30) includes an automatic metering inlet line (301), and a second constant pressure and constant flow pumping device (302) and a second shut-off valve (303) arranged sequentially on the automatic metering inlet line (301) along the reaction fluid delivery direction; wherein, the automatic metering inlet line (301) is used to automatically meter the amount of reaction fluid pumped to the reaction device (10) in real time.

3. The quantitative water-rock reaction experimental apparatus according to claim 2, characterized in that, The automatic metering inlet pipeline (301), the first constant pressure and constant flow pumping device (202), and the second constant pressure and constant flow pumping device (302) are respectively connected to the computer (50).

4. The quantitative water-rock reaction experimental apparatus according to claim 3, characterized in that, The computer (50) is configured to calculate the first target amount of the reaction fluid required to quantitatively control the water-rock reaction at the target reaction progress, and to automatically acquire in real time the amount of the reaction fluid pumped into the reaction device (10) from the automatic metering inlet line (301). When the reaction fluid pumped into the reaction device (10) by the second constant pressure and constant flow pumping device (302) reaches the first target amount, the computer (50) automatically controls the first constant pressure and constant flow pumping device (202) and the second constant pressure and constant flow pumping device (302) to shut down, stop pumping carbon dioxide and the reaction fluid into the reaction device (10), close the first shut-off valve (203) and the second shut-off valve (303), and stop the reaction.

5. The quantitative water-rock reaction experimental apparatus according to claim 4, characterized in that, The chemical signal acquisition includes at least the real-time hydrogen ion concentration acquisition of the reaction system within the reaction device (10).

6. The quantitative water-rock reaction experimental apparatus according to claim 5, characterized in that, The computer (50) is also configured to set a target pH value corresponding to the target reaction rate based on the first-order kinetics between the rock sample and the reaction fluid.

7. The quantitative water-rock reaction experimental apparatus according to claim 6, characterized in that, The computer (50) is further configured to automatically acquire the real-time hydrogen ion concentration from the chemical signal acquisition device (40), automatically convert it into a real-time pH value, and compare it with the target pH value; if the real-time pH value exceeds the target pH value, automatically calculate the second target amount of the reaction fluid required to adjust the real-time pH value to the target pH value; and automatically control the second constant pressure constant flow pumping device (302) to pump the second target amount of the reaction fluid into the reaction device (10) through the automatic metering inlet pipeline (301).

8. The quantitative water-rock reaction experimental apparatus according to claim 7, characterized in that, During the process of pumping the reaction fluid into the reaction device (10), the automatic metering inlet line (301) automatically meters the pumping volume of the reaction fluid in real time, and the chemical signal acquisition device (40) collects the hydrogen ion concentration of the reaction system in real time until the pumping volume of the reaction fluid obtained by the computer (50) from the automatic metering inlet line (301) reaches the second target volume, and the real-time pH value obtained from the real-time hydrogen ion concentration obtained from the chemical signal acquisition device (40) reaches the target pH value, so as to maintain the stability of the reaction rate.

9. The quantitative water-rock reaction experimental apparatus according to any one of claims 1 to 8, characterized in that, The quantitative water-rock reaction experimental device also includes a separation device (60), which is connected to the reaction device (10) through a liquid outlet pipeline (101) for collecting the reaction solution and the reaction rock sample from the reaction fluid for subsequent analysis and testing. On the liquid outlet pipeline (101), a back pressure valve (102) and a third shut-off valve (103) are respectively installed near the inlet and outlet of the separation device (60).

10. The quantitative water-rock reaction experimental apparatus according to claim 9, characterized in that, The base fluid is a sodium chloride-calcium chloride mixed solution; and / or the reaction fluid is an acid solution; Preferably, the salinity of the sodium chloride-calcium chloride mixed solution is the same as that of seawater; and / or The acid solution is dilute hydrochloric acid.

11. A quantitative water-rock reaction experimental method, characterized in that, The quantitative water-rock reaction experimental apparatus according to any one of claims 1 to 10 comprises the following steps: S1. Add the base fluid and rock sample to the reaction device (10), controllably supply carbon dioxide to the reaction device (10) through the carbon dioxide input device (20), and automatically and in real time supply the reaction fluid to the reaction device (10) through the reaction fluid input device (30) to carry out the water-rock reaction; S2. During the water-rock reaction process, the chemical signal acquisition device (40) acquires the chemical signal of the reaction device (10) in real time, and in conjunction with the reaction fluid input device (30), the reaction rate is kept stable under the control of the computer (50). S3. Using the computer (50) to acquire real-time chemical signals and the amount of reaction fluid delivered, control the amount of carbon dioxide and the amount of reaction fluid delivered to the reaction device (10) by the carbon dioxide input device (20) and the reaction fluid input device (30) respectively, and quantitatively control the reaction progress; when the water-rock reaction reaches the target reaction progress, stop the reaction and take samples for subsequent analysis and testing.

12. The method according to claim 11, characterized in that, The computer (50) calculates the first target amount of the reaction fluid required to quantitatively control the water-rock reaction at the target reaction progress; and / or sets the target pH value corresponding to the target reaction rate according to the first-order kinetics between the rock sample and the reaction fluid; Then proceed to step S1.

13. The method according to claim 12, characterized in that, In step S1, the back pressure valve (102), the third shut-off valve (103), and the first shut-off valve (203) are opened, and the first constant pressure and constant flow pumping device (202) is turned on to pump carbon dioxide into the reaction device (10) through the inlet pipeline (201); simultaneously, the second shut-off valve (303) is opened, and the second constant pressure and constant flow pumping device (302) is turned on to pump the reaction fluid into the reaction device (10) through the automatic metering inlet pipeline (301); the automatic metering inlet pipeline (301) automatically meters the pumping amount of the reaction fluid.

14. The method according to claim 13, characterized in that, In step S2, the real-time hydrogen ion concentration of the reaction system in the reaction device (10) is collected by the chemical signal acquisition device (40); the real-time hydrogen ion concentration is obtained from the chemical signal acquisition device (40) by the computer (50) and the real-time pH value is automatically calculated; the real-time pH value is automatically compared with the target pH value, and when the real-time pH value exceeds the target pH value, the second target amount of the reaction fluid required to adjust the real-time pH value to the target pH value is automatically calculated; Under the automatic control of the computer (50), the second target amount of the reaction fluid is pumped into the reaction device (10) through the second constant pressure and constant flow pumping device (302) and the automatic metering inlet pipeline (301).

15. The method according to claim 14, characterized in that, During the pumping process of the reaction fluid, the pumping volume of the reaction fluid is automatically measured in real time using the automatic metering inlet line (301), and the real-time hydrogen ion concentration in the reaction system is collected using the chemical signal acquisition device (40). The reaction rate of the water-rock reaction is maintained at the target reaction rate until the pumping volume of the reaction fluid obtained by the computer (50) from the automatic metering inlet line (301) reaches the second target amount and the real-time pH value obtained from the real-time hydrogen ion concentration from the chemical signal acquisition device (40) reaches the target pH value.

16. The method according to claim 15, characterized in that, In step S3, the computer (50) obtains the amount of the reaction fluid pumped into the reaction device (10) from the automatic metering inlet line (301). When the first target amount is reached, it means that the water-rock reaction has reached the target reaction progress. The computer (50) automatically controls the first constant pressure and constant flow pumping device (202) and the second constant pressure and constant flow pumping device (302) to shut down, stop pumping carbon dioxide and the reaction fluid into the reaction device (10), and close the first shut-off valve (203) and the second shut-off valve (303) to stop the reaction.

17. The method according to claim 16, characterized in that, In step S3, after the reaction is stopped, the post-reaction fluid is transported to the separation device (60) through the liquid outlet pipeline (101) for solid-liquid separation, and the post-reaction solution and post-reaction rock sample are collected.

18. The method according to claim 17, characterized in that, In step S3, the subsequent analytical tests include: detecting the hydrogen ion concentration in the solution after the reaction, the concentration of metal cations contained in the rock sample; and / or The surface morphology and mineral composition of the rock samples after the reaction were observed. Preferably, the concentration of the metal cation includes a calcium ion concentration or a magnesium ion concentration.

19. The method according to claim 18, characterized in that, Based on the hydrogen ion concentration and metal cation ion concentration in the solution after the reaction, calculate the changing trend of the carbonate ion product of the reaction fluid, estimate the dissolving capacity of the reaction fluid for the rock sample and the amount of carbonate precipitate produced; and / or Based on the microscopic morphology observation and mineral composition analysis of the post-reaction rock samples, the evolution of dissolution characteristics and the relationship between different reaction progresses are summarized, and the evolution law of reservoir internal storage space in open environment is analyzed and predicted.

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