A method for the full-cycle sequestration of carbon dioxide based on a multiphase reaction of a filling material

Abstract

This invention discloses a method for full-cycle carbon dioxide sequestration based on multiphase reaction filling materials, relating to the field of carbon sequestration, comprising the following steps: adding gaseous SiO2 and nano-CaO particles to the filling material as gas-entraining agents and transport enhancers; injecting CO2 gas into the filling slurry to form a gas-liquid two-phase dispersion system, and adding a surfactant with a mass fraction of 0.05%-0.2% to the filling slurry; transporting the filling slurry to the downhole filling area through a delivery pipeline, and installing an online rheometer in the delivery pipeline; after the filling slurry is injected into the goaf, injecting CO2 into at least one of the top, bottom, and sidewalls of the goaf through a gas injection pipeline until a gas-liquid-solid three-phase reaction interface is formed; monitoring its strain and acoustic emission signals in real time, and when a sudden change in signal is detected, determining that a new fracture has been generated or an existing fracture has expanded, and injecting CO2 gas into the target fracture through a pre-embedded gas injection pipeline.

Description

Technical Field

[0001] This invention relates to the field of carbon sequestration, and more particularly to a method for the full-cycle sequestration of carbon dioxide using multiphase reaction-based filling materials. Background Technology

[0002] Coal mining processes create numerous goaf areas, which not only pose risks such as spontaneous combustion of residual coal and water accumulation, but also cause surface subsidence and aquifer damage. Cemented backfill mining technology uses cement and other cementing materials to mix fly ash, coal gangue, and other coal-based solid wastes, preparing backfill materials for refilling the goaf areas, thereby controlling surface subsidence and disposing of solid waste. Meanwhile, the large amounts of CO2 emitted during coal production and utilization have become a pressing issue. CO2 capture, utilization, and storage technologies can effectively alleviate carbon emission pressures. Among these, mineralization storage can utilize cemented backfill materials as CO2 absorption carriers to achieve long-term geological CO2 sequestration.

[0003] Current research on CO2 sequestration in backfill materials mainly focuses on introducing CO2 during slurry mixing to sequester CO2 through carbonization reactions, or on CO2 curing of the prepared backfill. However, current research often focuses on a single stage, resulting in low carbon sequestration levels and failing to realize the carbon sequestration potential throughout the entire lifecycle of the backfill material. Therefore, proposing a method to achieve efficient and stable CO2 sequestration throughout the entire lifecycle of backfill materials is of great significance for promoting the construction of green mines and carbon emission reduction. Summary of the Invention

[0004] This solution addresses the problems and needs raised above by proposing a method for the full-cycle solidification of carbon dioxide using multiphase reaction-based filling materials. This method achieves the aforementioned technical objectives and brings about several other technical benefits due to the adoption of the following technical features.

[0005] The purpose of this invention is to propose a method for the full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions, comprising the following steps:

[0006] S10: At the ground mixing station, the filling material is poured into the mixing drum and water is added and mixed in proportion. Gas phase SiO2 and nano CaO particles are added to the mixture as air-entraining agents and transport enhancers to form the initial solid phase reaction interface.

[0007] S20: The captured industrial CO2 gas is injected into the stirred filling slurry in the form of a bubble group through a micron bubble generator to form a gas-liquid two-phase dispersion system, and a surfactant with a mass fraction of 0.05%-0.2% is added to the filling slurry.

[0008] S30: The above-mentioned filling slurry is transported to the downhole filling area through the delivery pipeline. At the same time, an online rheometer is installed in the delivery pipeline to monitor the yield stress and viscosity of the slurry in real time.

[0009] S40: After the filling slurry is injected into the goaf, CO2 is injected into at least one of the top, bottom and side walls of the goaf through the gas injection pipeline until a gas-liquid-solid three-phase reaction interface is formed.

[0010] S50: Distributed fiber optic sensors are pre-embedded at different elevations within the filling body to monitor its strain and acoustic emission signals in real time. When a sudden change in signal is detected, it is determined that a new crack has been generated or an existing crack has expanded, triggering a gas injection command. CO2 gas is injected into the target crack through the pre-embedded gas injection pipeline, and CO2 is adsorbed through the formed gas-solid two-phase system.

[0011] Furthermore, the method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to the present invention may also have the following technical features:

[0012] In one example of the present invention, in step S10, the mass fraction of fumed SiO2 added to the mixture is 0.01%-0.1%, and the mass fraction of nano-CaO particles is 0.01%-0.05%.

[0013] In one example of the present invention, in step S20, 1-3 minutes after the start of mixing the filling slurry, an injection of material with an average diameter of 50-200 mm is made into the slurry. CO2 microbubbles are injected at a pressure of 0.3-0.8 MPa, with a gas-liquid volume ratio of 0.1:1-0.3:1, for 3-10 minutes; the surfactant is a compound of sodium alkenyl sulfonate and polyether-modified siloxane.

[0014] In one example of the present invention, step S30 further includes: monitoring the yield stress and viscosity of the slurry using an online rheometer; when both exceed a set threshold, adding a trace amount of surfactant to ensure the conveyability of the slurry; wherein the yield stress inside the conveying pipeline... Stable at 0.5-2.0 MPa, plastic viscosity Maintain at 0.8-1.5 Pa Within the range of s.

[0015] In one example of the invention, yield stress and plastic viscosity The expressions are as follows:

[0016]

[0017]

[0018] In the formula, To monitor the pressure difference between the two ends of the pipeline section; D is the pipe diameter; L is the length of the straight pipeline section being monitored; k is the pipeline geometric constant. ; To monitor the velocity difference between the two ends of the pipeline section.

[0019] In one example of the present invention, in step S30, the inner wall of the delivery pipeline is coated with a hydrophobic and wear-resistant coating.

[0020] In one example of the present invention, step S40 specifically includes the following steps:

[0021] After the filling slurry is injected into the goaf for a first specified time, CO2 is injected into the top, bottom and sidewalls of the goaf through the gas injection pipeline for a second specified time. The top, bottom and sidewalls are used as the gas injection direction, and CO2 is injected in a cyclic pattern in sequence or in random combination. The gas injection direction is changed every third specified time. From the fourth specified time onwards, an intermittent gas injection mode is adopted to form a gas-liquid-solid three-phase reaction interface.

[0022] In one example of the present invention, in step S40, the air injection line is a rigid line with a one-way breathable membrane, the opening diameter of which is 0.1-1 mm. Between the two sides, only gas is allowed to pass through while preventing slurry or fine particles from entering; CO2 is injected from the top, bottom and side walls of the filling body at a pressure of 0.1-0.2MPa, with a CO2 volume fraction of 30%-70%, relative humidity ≥80%, and a micro pressure difference of 0.05-0.2MPa is maintained.

[0023] In one example of the present invention, in step S50, the injection pressure P of CO2 gas injected into the target fracture through the pre-embedded gas injection pipeline is dynamically adjusted according to the fracture width w, satisfying the following relationship:

[0024]

[0025] In the formula: P min P is the lower limit of pressure. max w1 is the upper limit of pressure; w1 is the crack width threshold; r is the pressure adjustment coefficient.

[0026] In one example of the present invention, in step S50, when the strain rate at a point in the filling body is continuously monitored to exceed 10... Furthermore, when the acoustic emission energy rate consistently exceeds 100 aJ / s, effective damage is determined to have occurred at that point. CO2 gas is then injected into the target fracture, where the mass of the CO2 injected in a single injection is... satisfy:

[0027]

[0028] In the formula: The mass of CO2 injected in a single targeted session; V is the density of CO2; c This is the estimated volume of the damage fracture.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. In the process of slurry mixing, the present invention introduces nano-additive CaO and surfactant compounded with sodium alkenyl sulfonate and polyether modified siloxane, which not only accelerates the precipitation of carbonates as nucleation sites, but also improves the suspension stability of the slurry by surface effect, preventing it from settling.

[0031] 2. This invention constructs a "gas-liquid-solid" multiphase reaction environment at different stages of the filling material. During the slurry stirring stage, it significantly improves the solubility and mineralization rate of CO2. During the condensation process of the filling material, it improves the penetration depth and uniform mineralization of gas in the filling body.

[0032] 3. This invention injects CO2 into the top, bottom and side walls of the goaf by pre-burying multiple sets of gas injection pipelines. Through the micropores formed in the early stage of solidification and hardening of the filling body, CO2 can penetrate into the interior of the filling body, which can improve the degree of carbonization reaction and thus increase the amount of CO2 fixed.

[0033] 4. This invention uses fiber optic sensors to sense and quantify the cracks in the filling material and inject CO2 in a directional manner, accurately controlling the injection amount, reducing CO2 waste, efficiently utilizing the cracks to adsorb CO2, and increasing the amount of CO2 fixed.

[0034] The preferred embodiments of the invention will be described in more detail below with reference to the accompanying drawings, so as to facilitate an understanding of the features and advantages of the invention. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. The drawings are merely illustrative of some embodiments of the present invention and are not intended to limit the scope of the present invention to all embodiments.

[0036] Figure 1 This is a flowchart of a method for full-cycle carbon dioxide solidification using filling materials based on multiphase reactions, according to an embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0038] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, “an” or “a” and similar terms do not necessarily indicate a quantity limitation. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0039] According to the present invention, a method for the full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions is provided, such as... Figure 1 As shown, it includes the following steps:

[0040] S10: At the ground mixing station, the filling material is poured into the mixing drum and water is added and mixed in proportion. Gas phase SiO2 and nano CaO particles are added to the mixture as air-entraining agents and transport enhancers to form the initial solid phase reaction interface.

[0041] S20: The captured industrial CO2 gas is injected into the stirred filling slurry in the form of a bubble group through a micron bubble generator to form a gas-liquid two-phase dispersion system, and a surfactant with a mass fraction of 0.05%-0.2% is added to the filling slurry.

[0042] S30: The above-mentioned filling slurry is transported to the downhole filling area by gravity or pumping through the delivery pipeline. At the same time, an online rheometer is installed on the pipe wall in the middle or end section of the delivery pipeline to monitor the yield stress and viscosity of the slurry in real time.

[0043] S40: After the filling slurry is injected into the goaf, CO2 is injected into at least one of the top, bottom and side walls of the goaf through the gas injection pipeline until a gas-liquid-solid three-phase reaction interface is formed.

[0044] S50: Distributed fiber optic sensors are pre-embedded at different elevations within the filling body to monitor its strain and acoustic emission signals in real time. When a sudden change in signal is detected, it is determined that a new crack has been generated or an existing crack has expanded, triggering a gas injection command. CO2 gas is injected into the target crack through the pre-embedded gas injection pipeline, and CO2 is adsorbed through the formed gas-solid two-phase system.

[0045] This carbon dioxide retention method introduces nano-additive CaO and a surfactant compounded with sodium alkenyl sulfonate and polyether-modified siloxane during slurry mixing. This not only acts as a nucleation site to accelerate carbonate precipitation but also enhances the suspension stability of the slurry through surface effects, preventing sedimentation. This method constructs a multiphase reaction environment of "gas-liquid-solid" at different stages of the filling material. During the slurry mixing stage, it significantly improves the solubility and mineralization rate of CO2. During the condensation process of the filling material, it increases the penetration depth and uniform mineralization of gas within the filling body. By injecting CO2 through multiple sets of pre-embedded gas injection pipelines at the top, bottom, and sidewalls of the goaf, CO2 permeates into the interior of the filling body through the micropores formed in the early stages of solidification and hardening, increasing the degree of carbonization reaction and thus improving the CO2 fixation. This method uses fiber optic sensors to detect and quantify the fractures in the filling body and inject CO2 directionally, precisely controlling the injection volume, reducing CO2 waste, and efficiently utilizing fractures to adsorb CO2, thereby increasing the CO2 fixation.

[0046] In one example of the present invention, in step S10, the mass fraction of fumed SiO2 added to the mixture is 0.01%-0.1%, and the mass fraction of nano-CaO particles is 0.01%-0.05%.

[0047] In one example of the present invention, in step S20, 1-3 minutes after the start of mixing the filling slurry, an injection of material with an average diameter of 50-200 mm is made into the slurry. CO2 microbubbles are injected at a pressure of 0.3-0.8 MPa, with a gas-liquid volume ratio of 0.1:1-0.3:1, for 3-10 minutes; the surfactant is a compound of sodium alkenyl sulfonate and polyether-modified siloxane.

[0048] In one example of the present invention, step S30 further includes: monitoring the yield stress and viscosity of the slurry using an online rheometer; when both exceed a set threshold, adding a trace amount of surfactant to ensure the conveyability of the slurry; wherein the yield stress inside the conveying pipeline... Stable at 0.5-2.0 MPa, plastic viscosity Maintain at 0.8-1.5 Pa Within the range of s.

[0049] In other words, by monitoring the yield stress and viscosity of the slurry using an online rheometer, and when both exceed a set threshold, a trace amount of surfactant is added to ensure the slurry's transportability; among these, the yield stress within the pipeline system... Stable at 0.5-2.0 MPa, plastic viscosity Maintain at 0.8-1.5 Pa Within the range of s; that is, the online rheometer includes pressure and flow sensors, and during the delivery process, it maintains the internal pressure of the pipeline system at 0.5-2.0 MPa and the viscosity at 0.8-1.5 Pa. Within the range of s.

[0050] In one example of the invention, yield stress and plastic viscosity The expressions are as follows:

[0051]

[0052]

[0053] In the formula, The pressure difference between the two ends of the monitoring section is measured in Pa; D is the pipe diameter in meters; L is the length of the straight section of the monitoring pipe in meters; and k is the pipe geometric constant. ; The velocity difference between the two ends of the monitoring pipeline is measured in m / s.

[0054] In one example of the present invention, in step S30, the inner wall of the delivery pipeline is coated with a hydrophobic and wear-resistant coating.

[0055] In one example of the present invention, step S40 specifically includes the following steps:

[0056] After the filling slurry is injected into the goaf for a first specified time, CO2 is injected into the top, bottom and sidewalls of the goaf through the gas injection pipeline for a second specified time. The top, bottom and sidewalls are used as the gas injection direction, and CO2 is injected in a cyclic pattern in sequence or in random combination. The gas injection direction is changed every third specified time. From the fourth specified time onwards, an intermittent gas injection mode is adopted to form a gas-liquid-solid three-phase reaction interface.

[0057] For example, 2-6 hours after the slurry is injected into the goaf, CO2 is injected from the top and bottom of the filling body at a pressure of 0.1-0.2 MPa through multiple sets of CO2 gas injection pipelines pre-embedded in the top, bottom and side walls of the goaf for 10-12 hours. Then, the top-bottom-side wall circulation mode is switched, and the main gas injection direction is changed every 4 hours to promote the three-dimensional uniform diffusion of CO2 in the filling body. From the 7th day, the intermittent gas injection mode is adopted to form a gas-liquid-solid three-phase reaction interface. The gas diffusion and mineralization reaction are enhanced by the circulation and intermittent gas injection modes.

[0058] In one example of the present invention, in step S40, the air injection line is a rigid line with a one-way breathable membrane, the opening diameter of which is 0.1-1 mm. Between the two sides, only gas is allowed to pass through while preventing slurry or fine particles from entering; CO2 is injected from the top, bottom and side walls of the filling body at a pressure of 0.1-0.2MPa, with a CO2 volume fraction of 30%-70%, relative humidity ≥80%, and a micro pressure difference of 0.05-0.2MPa is maintained.

[0059] In one example of the present invention, in step S50, the injection pressure P of CO2 gas injected into the target fracture through the pre-embedded gas injection pipeline is dynamically adjusted according to the fracture width w, satisfying the following relationship:

[0060]

[0061] In the formula: P min The lower pressure limit is 0.5 MPa; P max w1 is the upper limit of pressure, 3.0 MPa; w1 is the crack width threshold, 50 mm. ; r is the pressure regulation coefficient.

[0062] In one example of the present invention, in step S50, when the strain rate at a point in the filling body is continuously monitored to exceed 10... Furthermore, when the acoustic emission energy rate consistently exceeds 100 aJ / s, effective damage is determined to have occurred at that point. CO2 gas is then injected into the target fracture, where the mass of the CO2 injected in a single injection is... satisfy:

[0063]

[0064] In the formula: The mass of CO2 injected in a single targeted injection, in kg; The density of CO2 is kg / m³. 3 V c To estimate the damage fracture volume, m 3 .

[0065] Specific examples:

[0066] Taking mining area 2 of a certain mine as an example, the mining area level is -300m, and the goaf volume is 100,000 m³. 3 .

[0067] Step S10: At the ground mixing plant, pour 45%-55% full-size gangue, 35%-45% fly ash, and 5%-15% cement into the mixing drum and mix with water at a water-cement ratio of 0.5. 30 seconds after the start of mixing, add 0.01%-0.1% gaseous SiO2 and 0.01%-0.05% nano-CaO particles by mass to the mixture as air-entraining agent and transport enhancer to form the initial solid-phase reaction interface.

[0068] Step S20: Two minutes after the start of slurry stirring, the captured industrial CO2 gas is injected into the slurry in the form of a bubble cluster using a micron bubble generator to form a gas-liquid two-phase dispersion system. The injection pressure is 0.3-0.8 MPa, the gas-liquid volume ratio is 0.1:1-0.3:1, and the process is continued for 3-10 minutes. 0.05%-0.2% by mass of compounded sodium alkenyl sulfonate and polyether-modified siloxane is added to the slurry as a surfactant. This surfactant reduces the surface tension of the bubbles while improving the flow stability of the slurry. After injection, stirring is continued for 2 minutes to ensure that the CO2 bubbles and surfactant are fully dispersed.

[0069] Step S30: The filling slurry from Step S20 is pumped to the -300m horizontal filling area downhole via a centrifugal pump through a delivery pipeline with an inner wall coated with a polyurethane wear-resistant coating. During pumping, the pipeline system pressure is maintained within the range of 0.5-2.0MPa by a pressure stabilizing device to prevent dissolved CO2 from escaping due to pressure drop. Online tubular rheometers are installed at 200m and 300m from the wellhead of the delivery pipeline to monitor the yield stress and viscosity of the slurry in real time. When the yield stress of the slurry exceeds 200Pa or the viscosity exceeds 1.5Pa·s, a compound of sodium alkenyl sulfonate and polyether-modified siloxane with a mass fraction of 0.05%-0.1% is injected.

[0070] Step S40: 2-6 hours after the slurry is injected into the goaf, CO2 is injected from the top and bottom of the filling body at a pressure of 0.1-0.2 MPa through multiple sets of CO2 gas injection pipelines pre-embedded in the top, bottom and side walls of the goaf. The injection temperature is 25℃ and the relative humidity is 90%. The injection continues for 10-12 hours to form an upward and downward airflow, driving CO2 to penetrate into the filling body. Then, the "top-bottom-side" circulation mode is switched, and the main gas injection direction is changed every 4 hours. The sequence is: top gas injection 4 hours, stand for 1 hour, bottom gas injection 4 hours, stand for 1 hour, simultaneous gas injection on both sides of the side walls 4 hours, stand for 1 hour. This cycle continues. From the 7th day after filling, the intermittent gas injection mode is changed: gas is injected twice a day, each time from the top and bottom simultaneously for 3 hours, with an interval of 9 hours. This curing process continues until the 14th day after filling.

[0071] Step S50: Four sets of distributed fiber optic sensors are pre-embedded in the filling body at a vertical spacing of 10m to form a three-dimensional monitoring network for real-time monitoring of the strain and acoustic emission signals of the filling body. The strain rate threshold is set to 10. The acoustic emission energy rate threshold is 100 aJ / s. When the strain rate at a certain point in the filling material is continuously monitored to exceed 10... When the acoustic emission energy rate continuously exceeds 100 aJ / s, it is determined that effective damage has occurred at this point. High-pressure CO2 gas is injected into the target fracture network, and CO2 is adsorbed through the formed gas-solid two-phase adsorption.

[0072] This CO2 consolidation method can effectively control rock strata movement and optimize stress distribution in the mining area through backfilling. It can also efficiently consolidate CO2 through chemical mineralization reaction and physical pore adsorption. Furthermore, the backfilling material is mainly composed of coal-based solid waste, thus synergistically achieving the goals of efficient CO2 sequestration, rock strata movement control, and resource utilization of coal-based solid waste.

[0073] The foregoing description, with reference to preferred embodiments, details an exemplary implementation of the method for full-cycle carbon dioxide storage using multiphase reaction-based filling materials proposed in this invention. However, those skilled in the art will understand that various modifications and alterations can be made to the above specific embodiments without departing from the concept of this invention, and various combinations can be made to the various technical features and structures proposed in this invention without exceeding the protection scope of this invention, which is determined by the appended claims.

Claims

1. A method for the full-cycle sequestration of carbon dioxide based on a multiphase reaction of a filling material, characterized in that, Includes the following steps: S10: At the ground mixing station, the filling material is poured into the mixing drum and water is added and mixed in proportion. Gas phase SiO2 and nano CaO particles are added to the mixture as air-entraining agents and transport enhancers to form the initial solid phase reaction interface. S20: The captured industrial CO2 gas is injected into the stirred filling slurry in the form of a bubble group through a micron bubble generator to form a gas-liquid two-phase dispersion system, and a surfactant with a mass fraction of 0.05%-0.2% is added to the filling slurry. S30: The above-mentioned filling slurry is transported to the downhole filling area through the delivery pipeline. At the same time, an online rheometer is installed in the delivery pipeline to monitor the yield stress and viscosity of the slurry in real time. S40: After the filling slurry is injected into the goaf, CO2 is injected into at least one of the top, bottom and side walls of the goaf through the gas injection pipeline until a gas-liquid-solid three-phase reaction interface is formed. S50: Distributed fiber optic sensors are pre-embedded at different elevations within the filling body to monitor its strain and acoustic emission signals in real time. When a sudden change in signal is detected, it is determined that a new crack has been generated or an existing crack has expanded, triggering a gas injection command. CO2 gas is injected into the target crack through the pre-embedded gas injection pipeline, and CO2 is adsorbed through the formed gas-solid two-phase system.

2. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S10, the mass fraction of fumed SiO2 added to the mixture is 0.01%-0.1%, and the mass fraction of nano-CaO particles is 0.01%-0.05%.

3. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S20, 1-3 minutes after the filling slurry mixing begins, fillers with an average diameter of 50-200 mm are injected into the slurry. CO2 microbubbles are injected at a pressure of 0.3-0.8 MPa, with a gas-liquid volume ratio of 0.1:1-0.3:1, for 3-10 minutes; the surfactant is a compound of sodium alkenyl sulfonate and polyether-modified siloxane.

4. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, Step S30 further includes: monitoring the yield stress and viscosity of the slurry using an online rheometer; when both exceed a set threshold, adding a trace amount of surfactant to ensure the conveyability of the slurry; wherein, the yield stress inside the conveying pipeline... Stable at 0.5-2.0 MPa, plastic viscosity Maintain at 0.8-1.5 Pa Within the range of s.

5. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 4, characterized in that, Yield stress and plastic viscosity The expressions are as follows: wherein D is the pipe diameter; L is the length of the straight pipe section of the monitoring section; k is the pipe geometry constant, ; is the flow velocity difference between the two ends of the monitoring section pipe.

6. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S30, the inner wall of the delivery pipeline is coated with a hydrophobic and wear-resistant coating.

7. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, Step S40 specifically includes the following steps: After the filling slurry is injected into the goaf for a first specified time, CO2 is injected into the top, bottom and sidewalls of the goaf through the gas injection pipeline for a second specified time. The top, bottom and sidewalls are used as the gas injection direction, and CO2 is injected in a cyclic pattern in sequence or in random combination. The gas injection direction is changed every third specified time. From the fourth specified time onwards, an intermittent gas injection mode is adopted to form a gas-liquid-solid three-phase reaction interface.

8. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S40, the air injection line is a rigid line with a one-way breathable membrane, the opening diameter of which is 0.1-1 mm. Between the two sides, only gas is allowed to pass through while preventing slurry or fine particles from entering; CO2 is injected from the top, bottom and side walls of the filling body at a pressure of 0.1-0.2MPa, with a CO2 volume fraction of 30%-70%, relative humidity ≥80%, and a micro pressure difference of 0.05-0.2MPa is maintained.

9. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S50, the injection pressure P of CO2 gas injected into the target fracture through the pre-embedded gas injection pipeline is dynamically adjusted according to the fracture width w, satisfying the following relationship: wherein: P min is the lower pressure limit; P max is the upper pressure limit; w1 is the crack width threshold; r is the pressure regulation coefficient.

10. The method for full-cycle carbon dioxide sequestration using filling materials based on multiphase reactions according to claim 1, characterized in that, In step S50, when the strain rate at a point in the filling body is continuously monitored to exceed 10... Furthermore, when the acoustic emission energy rate consistently exceeds 100 aJ / s, effective damage is determined to have occurred at that point. CO2 gas is then injected into the target fracture, where the mass of the CO2 injected in a single injection is... satisfy: where: is the mass of CO2 for a single targeted injection; is the density of CO2; V c is the estimated damage fracture volume.

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