Device and method for monitoring porosity and permeability evolution in basalt in-situ mineralization process

Abstract

The invention discloses a device for monitoring porosity and permeability evolution in the basalt in-situ mineralization process, the device comprises a core holder, a permeability testing unit, a nuclear magnetic resonance unit, a temperature and pressure loading unit and a back pressure unit, and the invention also discloses a method for monitoring porosity and permeability evolution in the basalt in-situ mineralization process. The temperature and pressure loading unit and the back pressure unit are respectively used for applying confining pressure and back pressure to the basalt sample, so that the basalt sample is under real reservoir temperature and pressure and flow conditions, and the permeability testing unit is used for acquiring the volume of liquid flowing out of an output pipe of the core holder; according to the present invention, with the permeability testing unit and the nuclear magnetic resonance unit, the change of the porosity and the permeability under the flow reaction condition can be simultaneously and continuously monitored so as to overcome the problems of insufficient resolution and incapability of simultaneously monitoring the porosity and the permeability in the existing method.

Description

Technical Field

[0001] The invention belongs to the field of nuclear magnetic resonance technology, and specifically relates to a device for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, and also relates to a method for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, which is suitable for measuring the porosity and permeability of basalt samples during the mineralization reaction. Background Art

[0002] Global warming has caused problems such as melting glaciers, rising sea levels, and frequent extreme weather events. Solving the current climate crisis and achieving carbon emission reduction is urgent. As a fast-reacting and widely distributed basic rock, basalt can react quickly with CO2 to generate carbonate minerals, thereby permanently sealing CO2 in underground reservoirs, greatly reducing the risk of leakage and alleviating public concerns about CCUS (Carbon Capture, Utilization and Storage) technology. It is a favorable way to achieve carbon emission reduction.

[0003] However, during the CO2 injection process, processes such as fluid flow, particle migration, and mineral dissolution and precipitation will affect the porosity and permeability of the basalt reservoir, causing changes in the long-term injectability of the reservoir. Currently, CT or permeability displacement equipment is usually used to monitor the changes in porosity and permeability under basalt flow reaction conditions, but these methods have the problem of insufficient resolution and the inability to simultaneously monitor changes in porosity and permeability. Summary of the invention

[0004] The purpose of the present invention is to provide a device for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, and also to provide a method for monitoring the porosity and permeability evolution of basalt during in-situ mineralization in view of the above problems existing in the prior art.

[0005] The above-mentioned purpose of the present invention is achieved by the following technical means:

[0006] A device for monitoring porosity evolution during in-situ mineralization of basalt comprises a core holder, a reagent bottle, a balance scale, a permanent magnet, a nuclear magnetic probe coil, and a data collector. The core holder comprises a heat shrink tube and an outer cylinder, both ends of the outer cylinder are provided with plugs, the heat shrink tube is arranged inside the outer cylinder, both ends of the heat shrink tube are respectively connected to the plugs, one of the plugs is provided with an input tube connected to the heat shrink tube, and the other plug is provided with an output tube connected to the heat shrink tube. The reagent bottle is placed on the balance scale, the output tube of the core holder extends into the reagent bottle, the output tube of the core holder is provided with a fifth pressure gauge and a ninth needle valve, the input tube of the core holder is provided with a fourth pressure gauge and an eighth needle valve, the nuclear magnetic probe coil is connected to the data collector through a data line, the nuclear magnetic probe coil is wound outside the core holder, the permanent magnet is arranged outside the nuclear magnetic probe coil, the core holder and the nuclear magnetic probe coil are both located in the magnetic field generated by the permanent magnet, and the data collector is also connected to the balance scale through the data line.

[0007] A device for monitoring porosity and permeability evolution during in-situ mineralization of basalt also includes a confining pressure circulation pump, a preheater, and a back-pressure pump. Pipes at both ends of the confining pressure circulation pump pass through plugs at both ends of an outer tube and are connected to a confining pressure cavity formed between a heat shrink tube of a core holder and the outer tube. The preheater is arranged on the pipeline at one end of the confining pressure circulation pump. The output pipe of the back-pressure pump passes through a plug at one end of the outer tube and is connected to the heat shrink tube. A second pressure gauge and a fourth needle valve are arranged on the output pipe of the back-pressure pump. The input pipe of the back-pressure pump extends into a first container filled with water.

[0008] A device for monitoring porosity evolution during in-situ mineralization of basalt also includes a preparation syringe, a CO2 gas cylinder, a CO2 injection pump, and a pore pressure pump. The preparation syringe includes a push chamber and a preparation chamber, a piston is arranged between the push chamber and the preparation chamber, an output pipe of the preparation syringe is communicated with the preparation chamber, the output pipe of the preparation syringe is connected with an input pipe of a core clamp, a seventh needle valve is arranged on the output pipe of the preparation syringe, an input pipe of the CO2 injection pump is connected with the CO2 gas cylinder, the output pipe of the CO2 injection pump is communicated with the preparation chamber of the preparation syringe, a first pressure gauge, a first needle valve, and a second needle valve are arranged on the output pipe of the CO2 injection pump, the output pipe of the pore pressure pump is communicated with the push chamber of the preparation syringe, a third pressure gauge, a fifth needle valve, and a sixth needle valve are arranged on the output pipe of the pore pressure pump, and the input pipe of the pore pressure pump extends into a second container filled with water.

[0009] A device for monitoring porosity evolution during in-situ mineralization of basalt also includes a vacuum pump, an output pipe of the vacuum pump is connected to an input pipe of a core holder, and a third needle valve is arranged on the output pipe of the vacuum pump.

[0010] A method for monitoring the porosity and permeability evolution during in-situ mineralization of basalt, using the device for monitoring the porosity and permeability evolution during in-situ mineralization of basalt as described above, comprises the following steps:

[0011] Step 1: Keep all needle valves in a closed state, put the basalt sample into a heat shrink tube, and then install it in a core holder. Then, heat the confining pressure liquid to a set temperature through a preheater, pressurize the confining pressure liquid to a first set pressure through a confining pressure circulation pump, and then pass the confining pressure liquid of the first set pressure into the confining pressure cavity formed by the heat shrink tube and the outer cylinder to apply the set confining pressure to the basalt sample.

[0012] Step 2, fill the preparation chamber of the preparation syringe with pure water, extract high-purity CO2 from the CO2 cylinder with a CO2 injection pump, open the first needle valve and the second needle valve, and use the CO2 injection pump to inject CO2 of a second set pressure into the preparation chamber of the preparation syringe to obtain a saturated carbonic acid solution at the second set pressure for a set time;

[0013] Step 3, turn on the vacuum pump, then open the third needle valve and the eighth needle valve, use the vacuum pump to evacuate the inside of the heat shrink tube of the core holder, and close the third needle valve after the vacuum is evacuated;

[0014] Step 4, start the back pressure pump and open the fourth needle valve, use the back pressure pump to extract water, and pressurize the extracted water and pass it into the heat shrink tube to apply a specified back pressure to the basalt sample;

[0015] Step 5, open the fifth needle valve and the sixth needle valve, use the pore pressure pump to extract water and pressurize the extracted water to the third set pressure, and then pass it into the push chamber of the preparation syringe, push the piston of the preparation syringe by water pressure, and then open the seventh needle valve and the ninth needle valve, inject the saturated carbonic acid solution in the preparation chamber into the basalt sample, carry out the mineralization reaction under the in-situ flow condition, and use the reagent bottle to hold the liquid in the output tube of the core holder;

[0016] Step 6, measuring the T2 spectrum of the basalt sample during the mineralization reaction by a data acquisition device, and calculating the porosity of the basalt sample during the mineralization reaction;

[0017] Step 7: Use a balance scale to obtain the mass of the liquid flowing out of the output tube of the core holder in real time, and then obtain the volume of the liquid flowing out of the output tube of the core holder in real time, measure the pressure difference at both ends of the basalt sample by the fourth pressure gauge and the fifth pressure gauge, and calculate the permeability of the basalt sample during the mineralization reaction.

[0018] The porosity of the basalt sample during the mineralization reaction in step 6 as described above is calculated based on the following formula:

[0019]

[0020] Where t is the reaction time, is the porosity at reaction time t, T2 is the relaxation time, T2max and T2min are the maximum T2 relaxation time and the minimum T2 relaxation time during the displacement of the basalt sample, respectively, f(T2) is the signal amplitude corresponding to the T2 relaxation time, and V is the volume of the basalt sample.

[0021] The permeability of the basalt sample during the mineralization reaction in step 7 as described above is calculated based on the following formula:

[0022]

[0023] Among them, k t is the permeability at the reaction time t, Q is the volume of the liquid flowing out of the output tube of the core holder per unit time, μ is the dynamic viscosity of the saturated carbonic acid solution at the second set pressure, L and A are the length of the basalt sample and the cross-sectional area of ​​the end of the basalt sample, respectively, and ΔP is the pressure difference at both ends of the basalt sample.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The present invention can simultaneously and continuously monitor the changes in porosity and permeability under flow reaction conditions, overcoming the problems of insufficient resolution and inability to simultaneously monitor porosity and permeability in existing methods;

[0026] (2) The present invention places the basalt samples under real reservoir temperature, pressure and flow conditions;

[0027] (3) The present invention can obtain the evolution law of the pore structure of basalt samples during the mineralization reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a flow chart of the method of the present invention;

[0029] Figure 2 It is a schematic diagram of the structure of the device of the present invention;

[0030] Figure 3 It is a structural schematic diagram of the preparation injection barrel of the present invention;

[0031] Figure 4 The T2 spectrum of the basalt sample obtained during the reaction process using the device and method of the present invention (the ordinate Amplitude is the signal amplitude, and the abscissa is the T2 relaxation time);

[0032] Reference numerals and corresponding component names:

[0033] 1—core holder; 2—heat shrink tube; 3—basalt sample; 4—preheater; 5—confining pressure circulation pump; 6—CO2 gas cylinder; 7—CO2 injection pump; 8—first pressure gauge; 9—first needle valve; 10—second needle valve; 11—vacuum pump; 12—third needle valve; 13—first container; 14—back pressure pump; 15—second pressure gauge; 16—fourth needle valve; 17—second container; 18—pore pressure pump; 19—third pressure gauge; 20—fifth needle valve; 21—sixth needle valve; 22—preparation syringe; 23—seventh needle valve; 24—eighth needle valve; 25—fourth pressure gauge; 26—fifth pressure gauge; 27—ninth needle valve; 28—balance scale; 29—reagent bottle; 30—permanent magnet; 31—Nuclear magnetic probe coil; 32—data acquisition device. DETAILED DESCRIPTION

[0034] In order to facilitate those skilled in the art to understand and implement the present invention, the present invention is further described in detail below in conjunction with embodiments. The embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0035] Embodiment 1:

[0036] A device for monitoring porosity and permeability evolution during in-situ mineralization of basalt, comprising a core holder 1, a permeability test unit, and a nuclear magnetic resonance unit, wherein the core holder 1 comprises a heat shrink tube 2 (i.e., an inner tube of the core holder 1) and an outer tube, plugs are arranged at both ends of the outer tube, the heat shrink tube 2 is arranged inside the outer tube, and the two ends of the heat shrink tube 2 are respectively connected to the two plugs, the interlayer between the heat shrink tube 2 and the outer tube is a confining pressure chamber, one of the plugs is provided with an input tube connected to the heat shrink tube 2, and the other plug is provided with an output tube connected to the heat shrink tube 2, a basalt sample 3 is placed in the heat shrink tube 2, and the permeability test unit comprises a reagent bottle 29 and a balance scale 28, the reagent bottle 29 is placed on the balance scale 28 , the output pipe of the core holder 1 extends into the reagent bottle 29, the output pipe of the core holder 1 is provided with a fifth pressure gauge 26 and a ninth needle valve 27, the input pipe of the core holder 1 is provided with a fourth pressure gauge 25 and an eighth needle valve 24, the nuclear magnetic resonance unit comprises a permanent magnet 30, a nuclear magnetic probe coil 31, and a data acquisition device 32, the nuclear magnetic probe coil 31 is connected to the data acquisition device 32 via a data line, the nuclear magnetic probe coil 31 is wound around the outside of the core holder 1, the permanent magnet 30 is arranged outside the nuclear magnetic probe coil 31, the core holder 1 and the nuclear magnetic probe coil 31 are both located in the magnetic field generated by the permanent magnet 30, and the data acquisition device 32 is also connected to the balance scale 28 via a data line;

[0037] The reagent bottle 29 is used to hold the solution flowing out of the output tube of the core holder 1, and the balance scale 28 is used to obtain the mass of the solution in the reagent bottle 29 (that is, the mass of the solution flowing out of the output tube of the core holder 1), thereby obtaining the volume of the solution flowing out of the output tube of the core holder 1, and then calculating the flow rate of the solution flowing out of the output tube of the core holder 1; the permanent magnet 30 is used to provide a constant magnetic field, the nuclear magnetic probe coil 31 is used to transmit and receive nuclear magnetic pulse signals, and the data acquisition device 32 is used to collect and process the T2 spectrum signal during the reaction process. The data acquisition device 32 also obtains the mass of the reagent bottle 29 on the balance scale 28 in real time, thereby obtaining the mass of the solution in the reagent bottle 29 in real time.

[0038] It also includes a temperature and pressure loading unit and a back pressure unit. The temperature and pressure loading unit includes a confining pressure circulation pump 5 and a preheater 4. The pipelines at both ends of the confining pressure circulation pump 5 pass through the plugs at both ends of the outer tube and are connected to the confining pressure cavity formed between the heat shrink tube 2 of the core clamp 1 and the outer tube. The preheater 4 is arranged on the pipeline at one end of the confining pressure circulation pump 5. The back pressure unit includes a back pressure pump 14 and a first container 13. The output pipe of the back pressure pump 14 passes through the plug at one end of the outer tube and is connected to the heat shrink tube 2. The output pipe of the back pressure pump 14 is provided with a second pressure gauge 15 and a fourth needle valve 16. The input pipe of the back pressure pump 14 extends into the first container 13 filled with water.

[0039] The confining pressure circulation pump 5 passes the confining pressure liquid into the confining pressure chamber, and heats and pressurizes the confining pressure liquid in the core clamp 1 to the reservoir temperature and pressure conditions through the preheater 4; the back pressure pump 14 draws water from the first container 13, opens the fourth needle valve 16, and the back pressure pump 14 increases the drawn water to the set pressure and then injects it into the heat shrink tube 2 through the output pipe of the back pressure pump 14, and uses the water pressure to apply back pressure to the basalt sample 3.

[0040] The device also includes a preparation syringe 22, a CO2 injection unit, and a pushing unit. The preparation syringe 22 includes a pushing chamber and a preparation chamber. A piston is arranged between the pushing chamber and the preparation chamber. The output tube of the preparation syringe 22 is communicated with the preparation chamber. The output tube of the preparation syringe 22 is connected to the input tube of the core holder 1. A seventh needle valve 23 is arranged on the output tube of the preparation syringe 22. The CO2 injection unit includes a CO2 gas cylinder 6 and a CO2 injection pump 7. The input tube of the CO2 injection pump 7 is connected to the CO2 gas cylinder 6. Then, the output pipe of the CO2 injection pump 7 is communicated with the preparation chamber of the preparation syringe 22, and the output pipe of the CO2 injection pump 7 is provided with a first pressure gauge 8, a first needle valve 9, and a second needle valve 10, and the pushing unit includes a pore pressure pump 18 and a second container 17, the input pipe of the pore pressure pump 18 extends into the second container 17 filled with water, and the output pipe of the pore pressure pump 18 is communicated with the pushing chamber of the preparation syringe 22, and the output pipe of the pore pressure pump 18 is provided with a third pressure gauge 19, a fifth needle valve 20, and a sixth needle valve 21;

[0041] The piston divides the preparation syringe 22 into a pushing chamber and a preparation chamber; the CO2 injection pump 7 extracts high-purity CO2 from the CO2 cylinder 6, opens the first needle valve 9 and the second needle valve 10, and uses the CO2 injection pump 7 to inject 4MPa of CO2 into the preparation chamber of the preparation syringe 22 to obtain a saturated sodium carbonate solution under a pressure of 4MPa; the pore pressure pump 18 extracts water from the second container 17, opens the fifth needle valve 20 and the sixth needle valve 21, and the pore pressure pump 18 pressurizes the extracted water and injects it into the pushing chamber of the preparation syringe 22, uses the water pressure to push the piston in the preparation syringe 22, opens the seventh needle valve 23 and the eighth needle valve 24, and injects a saturated carbonic acid solution into the basalt sample 3 at a constant pressure of 4MPa.

[0042] It also includes a vacuum unit, which includes a vacuum pump 11. The output pipe of the vacuum pump 11 is connected to the input pipe of the core clamp 1, and a third needle valve 12 is arranged on the output pipe of the vacuum pump 11. The third needle valve 12 and the eighth needle valve 24 are opened, and the heat shrink tube 2 of the core clamp 1 is vacuumed by using the vacuum pump 11.

[0043] Embodiment 2:

[0044] A method for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, using the device for monitoring the porosity and permeability evolution of basalt during in-situ mineralization described in the above embodiment 1, comprises the following steps:

[0045] Step 1, keep all needle valves (i.e., the first needle valve 9 to the ninth needle valve 27) in a closed state, put the basalt sample 3 into the heat shrink tube 2, and then install it in the core clamp 1, then heat the confining pressure liquid to a set temperature through the preheater 4, use the confining pressure circulation pump 5 to pressurize the confining pressure liquid to a first set pressure, and then pass the confining pressure liquid of the first set pressure into the confining pressure cavity of the core clamp 1, thereby applying the set confining pressure to the basalt sample 3.

[0046] The basalt sample 3 in this embodiment has a diameter of 25 mm (millimeter), a length of 50 mm (millimeter), a set temperature of 40° C., and a set confining pressure of 10 MPa.

[0047] Step 2, fill the preparation chamber of the preparation syringe 22 with pure water, the CO2 injection pump 7 extracts high-purity CO2 (greater than or equal to 99.999%) from the CO2 cylinder 6, open the first needle valve 9 and the second needle valve 10, and use the CO2 injection pump 7 to inject CO2 of a second set pressure (such as 4MPa) into the preparation chamber of the preparation syringe 22 to obtain a saturated carbonic acid solution under the second set pressure, and the duration is 24 hours;

[0048] Step 3, start the vacuum pump 11, then open the third needle valve 12 and the eighth needle valve 24, use the vacuum pump 11 to evacuate the inside of the heat shrink tube 2 of the core holder 1, and close the third needle valve 12 after the vacuum is exhausted;

[0049] Step 4, start the back pressure pump 14 and open the fourth needle valve 16, use the back pressure pump 14 to extract water from the first container 13, and pressurize the extracted water and pass it into the heat shrink tube 2, so as to apply a specified back pressure to the basalt sample 3;

[0050] Step 5, open the fifth needle valve 20 and the sixth needle valve 21, use the pore pressure pump 18 to extract water from the second container 17 and pressurize the extracted water to the third set pressure, and then pass it into the driving chamber of the preparation injection cylinder 22, push the piston of the preparation injection cylinder 22 by water pressure, and then open the seventh needle valve 23 and the ninth needle valve 27, inject the saturated carbonic acid solution in the preparation chamber of the preparation injection cylinder 22 into the basalt sample 3, and carry out the mineralization reaction under the in-situ flow condition, and use the reagent bottle 29 to contain the liquid in the output pipe of the core holder 1;

[0051] Step 6: The T2 spectrum of the basalt sample 3 during the mineralization reaction is measured by the data acquisition device 32, the pore structure change rule is analyzed, and the porosity of the basalt sample 3 during the mineralization reaction is calculated according to the following formula:

[0052]

[0053] Where t is the reaction time, is the porosity at reaction time t, T2 is the relaxation time, T2max and T2min are the maximum T2 relaxation time (such as 10000) and the minimum T2 relaxation time (such as 0.001) during the displacement process of basalt sample 3, f(T2) is the signal amplitude corresponding to the T2 relaxation time, and V is the volume of basalt sample 3.

[0054] Step 7: Use the balance scale 28 to obtain the mass of the liquid flowing out of the output pipe of the core holder 1 in real time, and then obtain the volume of the liquid flowing out of the output pipe of the core holder 1 in real time, measure the pressure difference at both ends of the basalt sample 3 through the fourth pressure gauge 25 and the fifth pressure gauge 26, and calculate the permeability of the basalt sample 3 during the mineralization reaction according to the following formula:

[0055]

[0056] Among them, k tis the permeability at the reaction time t, Q is the outlet flow rate, that is, the volume of liquid flowing out of the output tube of the core holder 1 per unit time. In this embodiment, the mass change of the reagent bottle 29 per unit time can be measured by the balance scale 28, so as to obtain the change of the mass of the solution in the reagent bottle 29 per unit time, and then obtain the change of the volume of the solution in the reagent bottle 29 per unit time, that is, the volume of the liquid flowing out of the output tube of the core holder 1 per unit time, μ is the dynamic viscosity of the saturated carbonic acid solution under the second set pressure, L and A are the length of the basalt sample 3 and the cross-sectional area of ​​the end of the basalt sample 3, respectively, and ΔP is the pressure difference between the two ends of the basalt sample 3.

[0057] Table 1 shows the porosity of basalt sample 3 during the test and permeability k t Table of changes with reaction time t

[0058]

[0059]

[0060] pass Figure 4 It can be found that the pore structure change of basalt sample 3 is mainly the reduction of small pores.

[0061] It should be noted that the embodiments described in the present invention are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the described embodiments or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the attached claims.

Claims

1. A device for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, comprising a core holder (1), characterized in that: The invention also comprises a reagent bottle (29), a balance scale (28), a permanent magnet (30), a nuclear magnetic probe coil (31), and a data acquisition device (32). The core holder (1) comprises a heat shrink tube (2) and an outer tube. Both ends of the outer tube are provided with plugs. The heat shrink tube (2) is arranged inside the outer tube. Both ends of the heat shrink tube (2) are connected to the plugs respectively. One of the plugs is provided with an input tube connected to the heat shrink tube (2). The other plug is provided with an output tube connected to the heat shrink tube (2). The reagent bottle (29) is placed on the balance scale (28). The output tube of the core holder (1) extends into the reagent bottle (29). A fifth pressure gauge (26) and a ninth needle valve (27) are arranged on the output pipe of the core holder (1), a fourth pressure gauge (25) and an eighth needle valve (24) are arranged on the input pipe of the core holder (1), the nuclear magnetic probe coil (31) is connected to a data acquisition device (32) via a data line, the nuclear magnetic probe coil (31) is wound outside the core holder (1), a permanent magnet (30) is arranged outside the nuclear magnetic probe coil (31), the core holder (1) and the nuclear magnetic probe coil (31) are both located in the magnetic field generated by the permanent magnet (30), and the data acquisition device (32) is also connected to a balance scale (28) via a data line.

2. The device for monitoring porosity and permeability evolution during in-situ mineralization of basalt according to claim 1, characterized in that: It also includes a confining pressure circulation pump (5), a preheater (4), and a back-pressure pump (14); the pipelines at both ends of the confining pressure circulation pump (5) pass through the plugs at both ends of the outer tube and are connected to the confining pressure cavity formed between the heat shrink tube (2) of the core holder (1) and the outer tube; the preheater (4) is arranged on the pipeline at one end of the confining pressure circulation pump (5); the output pipe of the back-pressure pump (14) passes through the plug at one end of the outer tube and is connected to the heat shrink tube (2); a second pressure gauge (15) and a fourth needle valve (16) are arranged on the output pipe of the back-pressure pump (14); and the input pipe of the back-pressure pump (14) extends into a first container (13) filled with water.

3. The device for monitoring porosity and permeability evolution during in-situ mineralization of basalt according to claim 2, characterized in that: The invention also comprises a preparation syringe (22), a CO2 gas cylinder (6), a CO2 injection pump (7), and a pore pressure pump (18). The preparation syringe (22) comprises a driving chamber and a preparation chamber. A piston is arranged between the driving chamber and the preparation chamber. The output pipe of the preparation syringe (22) is connected to the preparation chamber. The output pipe of the preparation syringe (22) is connected to the input pipe of the core holder (1). A seventh needle valve (23) is arranged on the output pipe of the preparation syringe (22). The input pipe of the CO2 injection pump (7) is connected to the CO2 gas cylinder (6). The output pipe of the CO2 injection pump (7) is connected to the preparation chamber of the preparation syringe (22), and the output pipe of the CO2 injection pump (7) is provided with a first pressure gauge (8), a first needle valve (9), and a second needle valve (10). The output pipe of the orifice pressure pump (18) is connected to the push chamber of the preparation syringe (22), and the output pipe of the orifice pressure pump (18) is provided with a third pressure gauge (19), a fifth needle valve (20), and a sixth needle valve (21). The input pipe of the orifice pressure pump (18) extends into the second container (17) filled with water.

4. The device for monitoring porosity and permeability evolution during in-situ mineralization of basalt according to claim 3, characterized in that: It also comprises a vacuum pump (11), the output pipe of the vacuum pump (11) is connected to the input pipe of the core holder (1), and a third needle valve (12) is arranged on the output pipe of the vacuum pump (11).

5. A method for monitoring the porosity and permeability evolution of basalt during in-situ mineralization, using the device for monitoring the porosity and permeability evolution of basalt during in-situ mineralization according to claim 4, characterized in that: The following steps are involved: Step 1: Keep all needle valves in a closed state, put the basalt sample (3) into the heat shrink tube (2), and then install it in the core holder (1), then heat the confining pressure liquid to a set temperature through the preheater (4), pressurize the confining pressure liquid to a first set pressure through the confining pressure circulation pump (5), and then pass the confining pressure liquid at the first set pressure into the confining pressure cavity formed by the heat shrink tube (2) and the outer cylinder, and apply the set confining pressure to the basalt sample (3); Step 2, the preparation chamber of the preparation syringe (22) is filled with pure water, the CO2 injection pump (7) extracts high-purity CO2 from the CO2 cylinder (6), the first needle valve (9) and the second needle valve (10) are opened, and the CO2 injection pump (7) is used to inject CO2 of a second set pressure into the preparation chamber of the preparation syringe (22) to obtain a saturated carbonic acid solution at the second set pressure for a set time; Step 3, start the vacuum pump (11), then open the third needle valve (12) and the eighth needle valve (24), use the vacuum pump (11) to evacuate the inside of the heat shrink tube (2) of the core holder (1), and close the third needle valve (12) after the vacuum is evacuated; Step 4, start the back pressure pump (14) and open the fourth needle valve (16), use the back pressure pump (14) to extract water, and then pressurize the extracted water and pass it into the heat shrink tube (2), so as to apply a specified back pressure to the basalt sample (3); Step 5, open the fifth needle valve (20) and the sixth needle valve (21), use the pore pressure pump (18) to extract water and pressurize the extracted water to the third set pressure, then pass it into the driving chamber of the preparation injection cylinder (22), push the piston of the preparation injection cylinder (22) by water pressure, then open the seventh needle valve (23) and the ninth needle valve (27), inject the saturated carbonic acid solution in the preparation chamber into the basalt sample (3), carry out the mineralization reaction under the in-situ flow condition, and use the reagent bottle (29) to contain the liquid in the output pipe of the core holder (1); Step 6, measuring the T2 spectrum of the basalt sample (3) during the mineralization reaction by a data acquisition device (32), and calculating the porosity of the basalt sample (3) during the mineralization reaction; Step 7: Use a balance scale (28) to obtain in real time the mass of the liquid flowing out of the output pipe of the core holder (1), and then obtain in real time the volume of the liquid flowing out of the output pipe of the core holder (1), measure the pressure difference at both ends of the basalt sample (3) through the fourth pressure gauge (25) and the fifth pressure gauge (26), and calculate the permeability of the basalt sample (3) during the mineralization reaction.

6. A method for monitoring porosity and permeability evolution during in-situ mineralization of basalt according to claim 5, characterized in that: The porosity of the basalt sample (3) during the mineralization reaction in step 6 is calculated based on the following formula: Where t is the reaction time, is the porosity at reaction time t, T2 is the relaxation time, T2max and T2min are the maximum T2 relaxation time and the minimum T2 relaxation time during the displacement of basalt sample (3), f(T2) is the signal amplitude corresponding to the T2 relaxation time, and V is the volume of basalt sample (3).

7. A method for monitoring porosity and permeability evolution during in-situ mineralization of basalt according to claim 5, characterized in that: The permeability of the basalt sample (3) during the mineralization reaction in step 7 is calculated based on the following formula: Among them, k t is the permeability at the reaction time t, Q is the volume of liquid flowing out of the output pipe of the core holder (1) per unit time, μ is the dynamic viscosity of the saturated carbonic acid solution at the second set pressure, L and A are the length of the basalt sample (3) and the cross-sectional area of ​​the end of the basalt sample (3), respectively, and ΔP is the pressure difference between the two ends of the basalt sample (3).

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