Method and equipment for estimating carbon sequestration amount of abandoned mine

Abstract

The invention discloses an abandoned mine carbon sequestration amount estimation method and device, and relates to the technical field of carbon dioxide geological sequestration, and the method comprises the steps: determining a coal pillar total carbon reserve model based on coal pillar parameters and coal seam mining height in an abandoned mine; determining a caving zone total carbon reserve model based on caving zone parameters in the abandoned mine and coal seam mining height; determining a total carbon reserve model of the water-flowing fractured zone based on the parameters of the water-flowing fractured zone in the abandoned mine and the mining height of the coal seam; determining the sum of the coal pillar total carbon reserve model, the caving zone total carbon reserve model and the water flowing fractured zone total carbon reserve model as an initial model of the overall total carbon reserve of the abandoned mine, and simplifying the model; and completing the estimation of the overall total carbon reserve of the target abandoned mine by using the overall total carbon reserve model of the abandoned mine. According to the method, partition estimation and overall estimation are carried out on the carbon sequestration amount of the abandoned mine by constructing the overall total carbon reserve model of the abandoned mine.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of carbon dioxide geological storage, in particular to a waste mine carbon storage quantity estimation method and device. BACKGROUND

[0002] As the main greenhouse gas, carbon dioxide emission is the main cause of global warming. Reducing carbon emissions and achieving green and low-carbon development have become an important issue of common concern in the international community. Carbon dioxide geological storage technology, as an important means to cope with climate change, can effectively and long-term store carbon dioxide in geological reservoirs. At present, carbon dioxide storage technology includes various storage media, such as deep saline aquifers, waste mines and the like. Waste mines contain a large amount of residual coal and space resources, which can effectively adsorb and store carbon dioxide, providing multiple advantages for carbon dioxide geological storage. Therefore, there is an urgent need for a waste mine carbon storage quantity estimation technology. SUMMARY

[0003] The purpose of the application is to provide a waste mine carbon storage quantity estimation method and device, which can estimate the carbon storage quantity of waste mines in a partitioned manner and as a whole.

[0004] To achieve the above purpose, the application provides the following solutions: In a first aspect, the application provides a waste mine carbon storage quantity estimation method, comprising: determining a coal pillar total carbon storage quantity model based on coal pillar parameters and coal seam mining height in the waste mine; determining a caving zone total carbon storage quantity model based on caving zone parameters and coal seam mining height in the waste mine; determining a water flowing fractured zone total carbon storage quantity model based on water flowing fractured zone parameters and coal seam mining height in the waste mine; determining the sum of the coal pillar total carbon storage quantity model, the caving zone total carbon storage quantity model and the water flowing fractured zone total carbon storage quantity model as a waste mine overall total carbon storage quantity initial model; simplifying the waste mine overall total carbon storage quantity initial model based on geometric parameters of the waste mine to obtain a waste mine overall total carbon storage quantity model; determining the overall total carbon storage quantity estimation of a target waste mine by using the waste mine overall total carbon storage quantity model.

[0005] Optionally, the coal pillar total carbon storage quantity model is determined based on coal pillar parameters and coal seam mining height in the waste mine, and specifically comprises: determining the volume of the coal pillar according to the coal seam mining height and the geometric parameters of the coal pillar; determining the free-state content of carbon dioxide per unit volume of the coal pillar according to the carbon dioxide density of the coal pillar and the porosity of the coal; According to the coal density and the carbon dioxide pressure in the coal, the Langmuir equation is used to determine the carbon dioxide content in the coal column in an adsorbed state per unit volume; The sum of the carbon dioxide content in the coal column in a free state per unit volume and the carbon dioxide content in the coal column in an adsorbed state per unit volume is determined as the carbon dioxide content in the coal column per unit volume; The product of the coal column volume and the carbon dioxide content in the coal column per unit volume is determined as the total carbon storage model of the coal column.

[0006] Optionally, the coal column volume is: ; Wherein, V is the coal column volume; M is the mining height of the coal seam; is the coal column width; is the length of the working face tendency; The carbon dioxide content in the coal column in a free state per unit volume is: ; Wherein, is the carbon dioxide content in the coal column in a free state per unit volume; is the porosity of the coal; is the carbon dioxide density of the coal column; The carbon dioxide content in the coal column in an adsorbed state per unit volume is: ; Wherein, is the carbon dioxide content in the coal column in an adsorbed state per unit volume; is the carbon dioxide pressure in the coal; is the coal density; is the Langmuir volume parameter of carbon dioxide; is the Langmuir pressure parameter of carbon dioxide.

[0007] Optionally, based on the parameters of the caving zone in the abandoned mine and the mining height of the coal seam, a total carbon storage model of the caving zone is determined, which specifically includes: According to the mining height of the coal seam, the height of the caving zone is determined; According to the mining height of the coal seam, the height of the caving zone and the geometric parameters of the caving zone, the volume of the caving zone is determined; According to the porosity of the caving zone and the carbon dioxide pressure in the coal, the carbon dioxide content in the caving zone in a free state per unit volume is determined; According to the average density of the caving zone and the carbon dioxide pressure in the coal, the Langmuir equation is used to determine the carbon dioxide content in the caving zone in an adsorbed state per unit volume; The sum of the carbon dioxide content in the caving zone in a free state per unit volume and the carbon dioxide content in the caving zone in an adsorbed state per unit volume is determined as the carbon dioxide content in the caving zone per unit volume; The product of the caving zone volume and the caving zone unit volume carbon dioxide content is determined as a caving zone total carbon storage model.

[0008] Optionally, the caving zone height is: ; wherein, is the caving zone height; The caving zone volume is: ; ; ; wherein, is the working face strike length; and are intermediate parameters; is the rock breaking angle; The caving zone unit volume carbon dioxide free state content is: ; wherein, is the caving zone unit volume carbon dioxide free state content; is the caving zone porosity; The caving zone unit volume carbon dioxide adsorption state content is: ; ; wherein, is the caving zone unit volume carbon dioxide adsorption state content; is the caving zone rock average density; is the caving zone rock carbon dioxide average Langmuir volume parameter; is the caving zone rock carbon dioxide average Langmuir pressure parameter; is the density of the first, second and n layers of rock in the caving zone; is the adsorption volume constant of the first, second and n layers of rock in the caving zone; is the adsorption pressure constant of the first, second and n layers of rock in the caving zone.

[0009] Optionally, based on the water flowing fractured zone parameters in the abandoned mine and the coal seam mining height, a water flowing fractured zone total carbon storage model is determined, and specifically includes: According to the coal seam mining height, a water flowing fractured zone height is determined; According to the water flowing fractured zone height, a water flowing fractured zone volume is determined; According to the water flowing fractured zone porosity and the carbon dioxide pressure in the coal, a water flowing fractured zone unit volume carbon dioxide free state content is determined; Based on the average density of the rock strata in the water-conducting fracture zone and the carbon dioxide pressure in the coal, the Langmiur equation was used to determine the adsorbed carbon dioxide content per unit volume in the water-conducting fracture zone. The carbon dioxide content per unit volume of the water-conducting fracture zone is determined by the sum of the free carbon dioxide content per unit volume of the water-conducting fracture zone and the adsorbed carbon dioxide content per unit volume of the water-conducting fracture zone. The product of the volume of the water-conducting fracture zone and the carbon dioxide content per unit volume of the water-conducting fracture zone is determined as the model for the total carbon storage of the water-conducting fracture zone.

[0010] Optionally, the height of the water-conducting fracture zone is: ; in, The height of the water-conducting fracture zone; The volume of the water-conducting fracture zone is: ; ; ; in, The volume of the water-conducting fracture zone; and These are all intermediate parameters; The free carbon dioxide content per unit volume of the water-conducting fracture zone is: ; in, The free carbon dioxide content per unit volume of the water-conducting fracture zone; Porosity of the water-conducting fracture zone; The carbon dioxide adsorbed state content per unit volume of the water-conducting fracture zone is: ; ; in, The content of adsorbed carbon dioxide per unit volume in the water-conducting fracture zone; The average density of the rock strata in the water-conducting fracture zone; The average Langmuir volume parameter for carbon dioxide in the rock strata of the water-conducting fracture zone; The average Langmuir pressure parameter for carbon dioxide in the rock strata of the water-conducting fracture zone; is the density of the first, second, and nth rock layers in the fracture zone; represents the adsorption volume constants of the first, second, and nth rock layers in the fracture zone; is the adsorption pressure constant of the first, second, and nth rock layers in the fracture zone.

[0011] Optionally, the total carbon storage model of the whole abandoned mine is obtained by substituting the simplified formula into the initial model of the total carbon storage of the high water flowing fractured zone of the whole abandoned mine. The simplified formula is determined based on the geometric parameters of the abandoned mine.

[0012] Optionally, the simplified formula is: The total carbon storage model of the whole abandoned mine is:

[0013] In a second aspect, the present application provides a computer device, comprising: a memory, a processor to store a computer program on the memory and run the computer program on the processor, and the processor executes the computer program to implement the steps of the abandoned mine carbon storage estimation method according to any one of the above embodiments.

[0014] According to the specific embodiments provided by the present application, the following technical effects are disclosed: The present application provides an abandoned mine carbon storage estimation method and device, which calculates the volume of the residual coal pillar, the caving zone and the water flowing fractured zone of the abandoned mine, and the carbon storage per unit volume of each rock layer. The whole carbon storage of the abandoned mine is estimated, and the carbon dioxide storage capacity of the abandoned mine can be determined. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0016] Figure 1 The flow chart of an abandoned mine carbon storage estimation method in an embodiment of the present application is shown in FIG. 1. Figure 2 The simplified diagram of the "ladder-shaped" structure of the abandoned mine in an embodiment of the present application is shown in FIG. 2.

[0017] Figure 3 The flow chart of the process of establishing the total carbon storage model of the whole abandoned mine in an embodiment of the present application is shown in FIG. 3. DETAILED DESCRIPTION

[0018] ​​With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0019] The above-mentioned purposes, features and advantages of the present application can be more apparent and understandable. The present application will be described in further detail below with reference to the drawings and specific embodiments.

[0020] In an exemplary embodiment, as shown in Figure 1 a waste mine carbon storage estimation method is provided, comprising: Step 101: determining a coal pillar total carbon storage model based on coal pillar parameters and coal seam mining height in the waste mine.

[0021] Step 101 specifically comprises: determining the volume of the coal pillar according to the coal seam mining height and the geometric parameters of the coal pillar.

[0022] determining the free state content of carbon dioxide per unit volume of the coal pillar according to the carbon dioxide density of the coal pillar and the porosity of the coal.

[0023] determining the adsorbed state content of carbon dioxide per unit volume of the coal pillar by using the Langmiur equation according to the coal density and the carbon dioxide pressure in the coal.

[0024] determining the sum of the free state content of carbon dioxide per unit volume of the coal pillar and the adsorbed state content of carbon dioxide per unit volume of the coal pillar as the carbon dioxide content per unit volume of the coal pillar.

[0025] determining the product of the volume of the coal pillar and the carbon dioxide content per unit volume of the coal pillar as the coal pillar total carbon storage model.

[0026] Step 102: determining a caving zone total carbon storage model based on caving zone parameters and coal seam mining height in the waste mine.

[0027] Step 102 specifically comprises: determining the height of the caving zone according to the coal seam mining height.

[0028] determining the volume of the caving zone according to the coal seam mining height, the height of the caving zone and the geometric parameters of the caving zone.

[0029] determining the free state content of carbon dioxide per unit volume of the caving zone according to the porosity of the caving zone and the carbon dioxide pressure in the coal.

[0030] According to the average density of the rock stratum of the caving zone and the carbon dioxide pressure in the coal, the Langmiur equation is used to determine the content of the carbon dioxide in the adsorbed state per unit volume of the caving zone.

[0031] The sum of the content of the carbon dioxide in the free state per unit volume of the caving zone and the content of the carbon dioxide in the adsorbed state per unit volume of the caving zone is determined as the content of the carbon dioxide per unit volume of the caving zone.

[0032] The product of the volume of the caving zone and the content of the carbon dioxide per unit volume of the caving zone is determined as the total carbon storage model of the caving zone.

[0033] Step 103: Based on the water flowing fractured zone parameters in the abandoned mine and the mining height of the coal seam, the total carbon storage model of the water flowing fractured zone is determined.

[0034] Step 103, specifically comprising: According to the mining height of the coal seam, the height of the water flowing fractured zone is determined.

[0035] According to the height of the water flowing fractured zone, the volume of the water flowing fractured zone is determined.

[0036] According to the porosity of the water flowing fractured zone and the carbon dioxide pressure in the coal, the content of the carbon dioxide in the free state per unit volume of the water flowing fractured zone is determined.

[0037] According to the average density of the rock stratum of the water flowing fractured zone and the carbon dioxide pressure in the coal, the Langmiur equation is used to determine the content of the carbon dioxide in the adsorbed state per unit volume of the water flowing fractured zone.

[0038] The sum of the content of the carbon dioxide in the free state per unit volume of the water flowing fractured zone and the content of the carbon dioxide in the adsorbed state per unit volume of the water flowing fractured zone is determined as the content of the carbon dioxide per unit volume of the water flowing fractured zone.

[0039] The product of the volume of the water flowing fractured zone and the content of the carbon dioxide per unit volume of the water flowing fractured zone is determined as the total carbon storage model of the water flowing fractured zone.

[0040] Step 104: The sum of the total carbon storage model of the coal pillar, the total carbon storage model of the caving zone and the total carbon storage model of the water flowing fractured zone is determined as the initial model of the overall total carbon storage of the abandoned mine.

[0041] Step 105: Based on the geometric parameters of the abandoned mine, the initial model of the overall total carbon storage of the abandoned mine is simplified to obtain the overall total carbon storage model of the abandoned mine. The overall total carbon storage model of the abandoned mine is obtained by substituting the simplified formula into the initial model of the overall total carbon storage of the high water flowing fractured zone of the abandoned mine; the simplified formula is determined based on the geometric parameters of the abandoned mine; the geometric parameters of the abandoned mine are as shown in Figure 2 .

[0042] As Figure 3 shown in the overall total carbon storage model of the abandoned mine, the construction process is as follows: Step one: Obtain some basic information of the mine, such as the length of the mine, the height of the coal seam mining, etc.

[0043] Step two: According to the geological conditions of the mine and the mining height, the range of the "three zones" is calculated by the formula.

[0044] Further, the "three zones" of step two are respectively the caving zone, the water flowing fractured zone and the bending subsidence zone. The range of the bending subsidence zone is from the water flowing fractured zone to the overall stratum of the ground, and the cracks there are few and not considered.

[0045] Further, the caving zone refers to the area where the immediate roof of the coal seam collapses to form a rock pile after the working face is mined, and the calculation formula of the caving zone is: (1) Further, the water flowing fractured zone refers to the part above the caving zone, and the water flowing fractured zone has obvious zonation characteristics and a large number of developed cracks. The calculation formula of the water flowing fractured zone is: (2) In the formula, M is the height of the coal seam mining, m.

[0046] Step three: Calculate the total carbon storage of the coal pillar according to the carbon storage per unit volume of the residual coal pillar of the abandoned mine and the volume of the coal pillar.

[0047] Further, the calculation formula of the total carbon storage of the coal pillar in step three is: (3) In the formula, m 煤 is the carbon storage of the coal pillar, V is the volume of the coal pillar, m f is the adsorbed state content per unit volume of the coal pillar, m s is the free state content per unit volume of the coal pillar.

[0048] Further, the calculation formula of the volume of the coal pillar is: (4) In the formula, a is the width of the coal pillar, m; L b is the length of the working face, m.

[0049] Further, the calculation of the carbon storage per unit volume of the coal pillar includes the adsorbed state carbon storage per unit volume and the free state carbon storage per unit volume. The calculation formula of the free state CO2 content per unit volume of the coal is: (5) In the formula, Density of CO2 gas, kg / m 3 .

[0050] Further, the Langmuir equation is used to calculate the carbon storage of the adsorbed state per unit volume, and the calculation formula is: (6) In the formula, Density of coal, kg / m 3 ; Langmuir volume parameter of CO2, m 3 / kg; Pressure of CO2 in coal, MPa; Langmuir pressure parameter of CO2, MPa.

[0051] Further, the total carbon storage calculation formula of the coal pillar is: (7) Step four: calculate the carbon storage of the caving zone according to the carbon storage per unit volume of the caving zone and the volume of the caving zone.

[0052] Further, the total carbon storage calculation formula of the caving zone is: (8) In the formula, m 跨 Carbon storage of the caving zone, V 跨 Volume of the caving zone, m fk Adsorbed state content per unit volume of the caving zone, m sk Free state content per unit volume of the caving zone.

[0053] Further, since the structure of the overburden strata of the goaf formed after the coal seam is mined is approximately "trapezoidal", the volume of the caving zone is calculated according to the "trapezoidal" structure. The calculation formula is: (9) In the formula, L a Length of the working face, m; 、 The two parameters are calculated by the length of the working face and the length of the working face, and the calculation formula is: Wherein Rock breaking angle.

[0054] Further, 、 Two parameters into the formula (8) can be obtained by the volume of the collapse zone calculation formula: (10) Further, the calculation of the free state of carbon storage per unit volume of collapse zone, the calculation formula is: (11) In the formula, The porosity of the collapse zone.

[0055] Further, the calculation of the free state of carbon storage per unit volume of collapse zone, the calculation formula is: (12) In the formula, The average density of the collapse zone rock, kg / m 3 ; The average CO2 Langmuir volume parameter of the collapse zone rock, m 3 / kg; The average CO2 Langmuir pressure parameter of the collapse zone rock, MPa.

[0056] Therefore, the calculation formula of the free state of carbon storage per unit volume of collapse zone is: (13) Further, the total carbon storage of the collapse zone can be obtained by the calculation formula (14) Step five: according to the waste mine water flowing fractured zone unit volume carbon storage and water flowing fractured zone volume to calculate the carbon storage of water flowing fractured zone.

[0057] Further, the total carbon storage of the collapse zone can be obtained by the calculation formula: (15) In the formula, m 裂 The carbon storage of the water flowing fractured zone, V 裂 The volume of the water flowing fractured zone, m fl The unit volume of the water flowing fractured zone, m sl The unit volume of the water flowing fractured zone Further, the volume of the water flowing fractured zone is calculated according to the "trapezoidal" structure. The calculation formula is: (16) wherein, , Two parameters are also calculated according to the length of the working face and the length of the working face, and the calculation formula is .

[0058] Therefore, the volume calculation formula of the water flowing fractured zone is: (17) Further, the free state carbon storage of the water flowing fractured zone per unit volume is calculated, and the calculation formula is: (18) wherein, is the porosity of the water flowing fractured zone.

[0059] Further, the adsorbed state carbon storage of the water flowing fractured zone per unit volume is calculated, and since the water flowing fractured zone contains various rock layers, the average value method is used to calculate the density of the rock layer of the water flowing fractured zone and the Langmuir adsorption parameters of the rock layer to CO2, and the calculation formula is: (19) wherein, is the average density of the rock layer of the water flowing fractured zone, kg / m 3 ; is the average CO2 Langmuir volume parameter of the rock layer of the water flowing fractured zone, m 3 / kg; is the average CO2 Langmuir pressure parameter of the rock layer of the water flowing fractured zone, MPa; is the adsorption pressure constant of the first, second and n layers of rock layers in the fractured zone.

[0060] Therefore, the calculation formula of the adsorbed state carbon storage per unit volume of the water flowing fractured zone is: (20) Further, the carbon storage calculation formula of the water flowing fractured zone can be obtained as: (21) Step six: add the carbon storage formulas of each part calculated in steps three to five to obtain the total carbon storage calculation formula of the abandoned mine: (22) Since the length of the inclination of the goaf of the abandoned mine is much larger than the length of the working face, the model is further simplified when calculating the total carbon storage, so that , the simplified total carbon storage estimation model of the abandoned mine is: (23) Step 106: Determine the total carbon storage capacity of the target abandoned mine by using the total carbon storage capacity model of the abandoned mine.

[0061] The estimation method of the carbon storage capacity of the abandoned mine provided in this embodiment includes: based on the gas distribution characteristics in the reservoir of the abandoned mine and the calculation method of the unit volume storage capacity of each reservoir. Based on the gas distribution characteristics in the reservoir of the abandoned mine: after the mine is mined, the original balance state of its internal structure is destroyed, due to pressure balance, the injected gas and the internally occurring gas will be redistributed in the coal pillar, the caving zone and the water flowing fractured zone. The pores and functional groups existing in the coal pillar make the gas exist in the coal pillar in the form of adsorption and free state, the caving zone is formed by the stacking of floating coal and collapsed rocks, so the internal cracks are large and contain free gas and adsorbed gas, and the water flowing fractured zone is generated due to the separation between the rock layers, and the internal gas exists in the form of free state and a small amount of adsorption state. The calculation method of the unit volume storage capacity of each reservoir, including the calculation of the unit volume carbon storage capacity and the volume of the residual coal pillar, the calculation of the unit volume carbon storage capacity and the volume of the overburden caving zone above the goaf, and the calculation of the unit volume carbon storage capacity and the volume of the water flowing fractured zone above the overburden caving zone which contains a large number of longitudinal and transverse water flowing fractures. The application calculates the carbon dioxide storage capacity stored in the abandoned mine by corresponding formula derivation, realizes effective estimation of the carbon storage capacity, and realizes efficient utilization of the internal space of the abandoned mine.

[0062] Next, taking a specific target abandoned mine as an example, the building process of the total carbon storage capacity model of the abandoned mine in this embodiment is specifically described.

[0063] Step one: Obtain some basic information of the mine, such as the mine advancing length, coal seam mining height and the like.

[0064] Step two: Calculate the range of the "three zones" according to the mine geological conditions and the mining height by using the formula.

[0065] Further, the "three zones" of step two are respectively the caving zone, the water flowing fractured zone and the curved subsidence zone. The range of the curved subsidence zone is the stratum from the water flowing fractured zone to the ground as a whole, and the cracks there are few and are not considered.

[0066] Further, the caving zone refers to the area where the rock heap is formed by the caving of the immediate roof of the coal seam after the working face is mined, and the caving zone height is: .

[0067] Considering safety, take .

[0068] Further, the water-conducting fracture zone refers to the part of the zone above the falling zone, and the water-conducting fracture zone has obvious zonation characteristics and a large number of developed fractures, and the height of the water-conducting fracture zone is: .

[0069] In the formula, M is the height of the coal seam mining, 7.5 m.

[0070] Take .

[0071] Step three: calculate the total carbon storage of the coal pillar according to the carbon storage per unit volume of the residual coal pillar of the abandoned mine and the volume of the coal pillar.

[0072] Further, the total carbon storage calculation formula of the coal pillar in step three is: .

[0073] In the formula, m 煤 is the carbon storage of the coal pillar, V is the volume of the coal pillar, m f is the adsorbed content per unit volume of the coal pillar, m s is the free content per unit volume of the coal pillar.

[0074] Further, the volume of the coal pillar is: .

[0075] In the formula, a is the width of the coal pillar, 5 m; L b is the length of the working face tendency, 912 m.

[0076] Further, the calculation of the carbon storage per unit volume of the coal pillar includes the adsorbed carbon storage per unit volume and the free carbon storage per unit volume, and the free CO2 content per unit volume in the coal is: .

[0077] In the formula, φ is the porosity of the coal, taken as 0.06; is the density of CO2 gas, taken as 1.8 kg / m 3 .

[0078] Further, the adsorbed carbon storage per unit volume is calculated by using the Langmiur equation, and the value is: .

[0079] In the formula, is the density of the coal, taken as 1.3 x 10 3 kg / m3 ; Langmuir volume parameter of CO2, 0.092 m 3 / kg; Pressure of CO2 in coal, 3.2 MPa; Langmuir pressure parameter of CO2, 1.57 MPa.

[0080] Further, the total carbon storage of the coal pillar can be obtained as: .

[0081] Step four: calculate the carbon storage of the caving zone according to the unit volume carbon storage of the caving zone of the abandoned mine and the volume of the caving zone.

[0082] Further, the calculation formula of the total carbon storage of the caving zone is: .

[0083] In the formula, m 跨 carbon storage of the caving zone, V 跨 volume of the caving zone, m fk unit volume adsorbed content of the caving zone, m sk unit volume free state content of the caving zone.

[0084] Further, since the structure of the overburden strata of the goaf formed after the coal seam is mined is approximately "trapezoidal", the volume of the caving zone is calculated according to the "trapezoidal" structure: .

[0085] In the formula, L a length of the working face, 191 m; 、 The two parameters are calculated from the length of the working face and the length of the working face, , break angle of the rock stratum, 65°.

[0086] Further, the two parameters are substituted into formula (8) to obtain the volume of the caving zone: . .

[0087] Further, the unit volume free state carbon storage of the caving zone is calculated as: .​

[0088] wherein, is the porosity of the caving zone, taken as 0.25.

[0089] Further, the adsorbed carbon storage of the caving zone per unit volume is calculated. Since the caving zone contains various rock layers and residual coal, the average method is used to calculate the density of the rock layer of the caving zone and the Langmuir adsorption parameters of the rock layer to CO2: .

[0090] wherein, is the average density of the rock layer of the caving zone, kg / m 3 ; is the average Langmuir volume parameter of CO2 of the rock layer of the caving zone, m 3 / kg; is the average Langmuir pressure parameter of CO2 of the rock layer of the caving zone, MPa.

[0091] The rock layer of the caving zone is medium sandstone and fine sandstone, and the densities are taken as 2.6 kg / m 3 and 2.4 kg / m 3 , respectively. The Langmuir volume parameters of CO2 of the rock layer are taken as 0.0055 m 3 / kg and 0.0065 m 3 / kg, respectively. The Langmuir pressure parameters of CO2 of the rock layer are taken as 3 MPa and 5 MPa, respectively.

[0092] Therefore, the adsorbed carbon storage of the caving zone per unit volume is: .

[0093] Further, the total carbon storage of the caving zone can be obtained as: .

[0094] Step five: calculate the carbon storage of the water flowing fractured zone according to the carbon storage per unit volume of the water flowing fractured zone of the abandoned mine and the volume of the water flowing fractured zone.

[0095] Further, the calculation formula of the total carbon storage of the water flowing fractured zone is: .

[0096] wherein, m 裂 is the carbon storage of the water flowing fractured zone, V 裂 is the volume of the water flowing fractured zone, m fl is the adsorbed content per unit volume of the water flowing fractured zone,m sl This represents the free state content per unit volume of the water-conducting fracture zone.

[0097] Furthermore, the volume of the water-conducting fracture zone is calculated based on a "trapezoidal" structure: .

[0098] In the formula, , Both parameters are calculated based on the strike length and dip length of the working face: .

[0099] Therefore, the volume of the water-conducting fracture zone is: .

[0100] Furthermore, the free carbon storage per unit volume in the water-conducting fracture zone is calculated: .

[0101] In the formula, The porosity of the water-conducting fracture zone is taken as 0.15.

[0102] Furthermore, the adsorbed carbon storage per unit volume in the water-conducting fracture zone was calculated. Since the water-conducting fracture zone contains multiple rock layers, the density of the rock layers in the water-conducting fracture zone and the Langmuir adsorption parameters of the rock layers for CO2 were calculated using the average value method. .

[0103] In the formula, The average density of the rock strata in the water-conducting fracture zone is kg / m³. 3 ; The Langmuir volumetric parameter for the average CO2 of the water-conducting fracture zone strata is given in m. 3 / kg; The Langmuir pressure parameter for average CO2 in the water-conducting fracture zone strata is given in MPa.

[0104] The water-conducting fracture zone consists of medium sandstone, fine sandstone, siltstone, and mudstone, with densities of 2.6 kg / m³. 3 2.4kg / m 3 2.3kg / m 3 and 2.3kg / m 3 The Langmuir volume parameters of CO2 in the rock strata were taken as 0.0055 m. 3 / kg, 0.0065m 3 / kg, 0.007m 3 / kg and 0.005m3 kg, and the Langmuir pressure parameters of the stratum CO2 are respectively taken as 3 MPa, 5 MPa, 5.5 MPa and 2.5 MPa.

[0105] Therefore, the carbon storage of the water flowing fractured zone per unit volume in the adsorbed state is: .

[0106] Further, the carbon storage of the water flowing fractured zone is obtained as: .

[0107] Step six: adding the carbon storage formulas of each part calculated in steps three to five, to obtain the calculation formula of the total carbon storage of the abandoned mine: .

[0108] The total carbon storage of the abandoned mine is calculated as: .

[0109] In an exemplary embodiment, a computer device is provided, which can be a server or a terminal. The computer device includes a processor, a memory, an input / output interface (I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The input / output interface of the computer device is configured to exchange information between the processor and external devices. The communication interface of the computer device is configured to communicate with external terminals through a network connection.

[0110] In an exemplary embodiment, a computer device is provided, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0111] In an exemplary embodiment, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to implement the steps in the above method embodiments.

[0112] In an exemplary embodiment, a computer program product is provided, which includes a computer program. The computer program is executed by a processor to implement the steps in the above method embodiments.

[0113] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant regulations.

[0114] It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program, and the computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments of each method. Among them, any reference to memory, database or other medium used in each embodiment provided by the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (Read-Only Memory, ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric memory (Ferroelectric Random Access Memory, FRAM), phase change memory (Phase Change Memory, PCM), graphene memory, etc. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc.

[0115] The database involved in each embodiment provided by the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in each embodiment provided by the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0116] Each technical feature of the above embodiments can be combined arbitrarily. In order to make the description simple, not all possible combinations of each technical feature in the above embodiments are described, but as long as the combination of these technical features does not exist contradictory, it should be considered as the scope of the present application.

[0117] The principles and implementations of the present application are described in the specific examples used herein, and the above examples are only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation and application range will be changed. Therefore, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A method of estimating the amount of carbon sequestration in abandoned mines, characterized by, The method comprises the following steps: Based on the coal pillar parameters in the abandoned mine and the coal seam mining height, a coal pillar total carbon storage model is determined; Based on the caving zone parameters in the abandoned mine and the coal seam mining height, a caving zone total carbon storage model is determined; Based on the water flowing fractured zone parameters in the abandoned mine and the coal seam mining height, a water flowing fractured zone total carbon storage model is determined; The sum of the coal pillar total carbon storage model, the caving zone total carbon storage model and the water flowing fractured zone total carbon storage model is determined as an initial model of the overall total carbon storage of the abandoned mine; Based on the geometric parameters of the abandoned mine, the initial model of the overall total carbon storage of the abandoned mine is simplified to obtain a model of the overall total carbon storage of the abandoned mine; The overall total carbon storage estimation of the target abandoned mine is determined by using the model of the overall total carbon storage of the abandoned mine.

2. The method of claim 1, wherein, Based on the coal pillar parameters in the abandoned mine and the coal seam mining height, a coal pillar total carbon storage model is determined, which specifically comprises the following steps: The volume of the coal pillar is determined according to the coal seam mining height and the geometric parameters of the coal pillar; The free state content of carbon dioxide per unit volume of the coal pillar is determined according to the carbon dioxide density of the coal pillar and the porosity of the coal; The adsorbed state content of carbon dioxide per unit volume of the coal pillar is determined by using the Langmiur equation according to the coal density and the carbon dioxide pressure in the coal; The sum of the free state content of carbon dioxide per unit volume of the coal pillar and the adsorbed state content of carbon dioxide per unit volume of the coal pillar is determined as the carbon dioxide content per unit volume of the coal pillar; The product of the volume of the coal pillar and the carbon dioxide content per unit volume of the coal pillar is determined as the coal pillar total carbon storage model.

3. The method of claim 1, wherein, The volume of the coal pillar is: ； Wherein, V is the volume of coal pillar; M is the mining height of coal seam; is the width of coal pillar; is the length of working face inclination; The free state content of carbon dioxide per unit volume of the coal pillar is: ； wherein, is the carbon dioxide free state content per unit volume of the coal pillar; is the porosity of the coal; is the carbon dioxide density of the coal pillar; The adsorbed state content of carbon dioxide per unit volume of the coal pillar is: ； wherein, is the carbon dioxide adsorbed content per unit volume of coal pillar; is the carbon dioxide pressure in the coal; is the coal density; is the Langmuir volume parameter for carbon dioxide; is the Langmuir pressure parameter for carbon dioxide.

4. The method of claim 3, wherein, Based on the caving zone parameters in the abandoned mine and the coal seam mining height, a caving zone total carbon storage model is determined, which specifically comprises the following steps: The height of the caving zone is determined according to the coal seam mining height; The volume of the caving zone is determined according to the coal seam mining height, the height of the caving zone and the geometric parameters of the caving zone; The free state content of carbon dioxide per unit volume of the caving zone is determined according to the porosity of the caving zone and the carbon dioxide pressure in the coal; The adsorbed state content of carbon dioxide per unit volume of the caving zone is determined by using the Langmiur equation according to the average density of the rock stratum of the caving zone and the carbon dioxide pressure in the coal; The sum of the free state content of carbon dioxide per unit volume of the caving zone and the adsorbed state content of carbon dioxide per unit volume of the caving zone is determined as the carbon dioxide content per unit volume of the caving zone; The product of the volume of the caving zone and the carbon dioxide content per unit volume of the caving zone is determined as the caving zone total carbon storage model.

5. The method of claim 4, wherein, The height of the caving zone is: ； wherein Hc is the height of the caving zone; The volume of the caving zone is: ； ； ； wherein, is the working face strike length; and are both intermediate parameters; is the rock break angle; The free state content of carbon dioxide per unit volume of the caving zone is: ； wherein, is the free state carbon dioxide content per unit volume of the caving zone; is the porosity of the caving zone. The adsorbed state content of carbon dioxide per unit volume of the caving zone is: ； ； wherein, is the carbon dioxide adsorbed content per unit volume of the caving zone; is the average density of the rock strata of the caving zone; is the average Langmuir volume parameter for carbon dioxide of the rock strata of the caving zone; is the average Langmuir pressure parameter for carbon dioxide of the rock strata of the caving zone; is the density of the 1st, 2nd, and n-th rock strata in the caving zone; is the adsorption volume constant of the 1st, 2nd, and n-th rock strata in the caving zone; is the adsorption pressure constant of the 1st, 2nd, and n-th rock strata in the caving zone.

6. The method of estimating abandoned mine carbon storage according to claim 5, wherein, Based on the water flowing fractured zone parameters in the abandoned mine and the coal seam mining height, a water flowing fractured zone total carbon storage model is determined, which specifically comprises the following steps: The height of the water flowing fractured zone is determined according to the coal seam mining height; The volume of the water flowing fractured zone is determined according to the height of the water flowing fractured zone; The free state content of carbon dioxide per unit volume of the water flowing fractured zone is determined according to the porosity of the water flowing fractured zone and the carbon dioxide pressure in the coal; According to the average density of the water flowing fractured zone and the carbon dioxide pressure in the coal, the Langmiur equation is used to determine the carbon dioxide content in the unit volume of the water flowing fractured zone in the adsorbed state; The sum of the carbon dioxide content in the unit volume of the water flowing fractured zone in the free state and the carbon dioxide content in the unit volume of the water flowing fractured zone in the adsorbed state is determined as the carbon dioxide content in the unit volume of the water flowing fractured zone; The product of the volume of the water flowing fractured zone and the carbon dioxide content in the unit volume of the water flowing fractured zone is determined as the total carbon storage model of the water flowing fractured zone.

7. The method of estimating abandoned mine carbon storage according to claim 6, wherein, The height of the water flowing fractured zone is: ； wherein, H is the height of the water conducting fracture zone; The volume of the water flowing fractured zone is: ； ； ； wherein is the volume of the water conducting fracture zone; and are both intermediate parameters; The carbon dioxide content in the unit volume of the water flowing fractured zone in the free state is: ； wherein, is the free state carbon dioxide content per unit volume of the water conducting fracture zone; is the porosity of the water conducting fracture zone. The carbon dioxide content in the unit volume of the water flowing fractured zone in the adsorbed state is: ； ； wherein, is the carbon dioxide adsorbed content per unit volume of the water- conducting fracture zone; is the average density of the rock strata of the water-conducting fracture zone; is the average Langmuir volume parameter for carbon dioxide of the rock strata of the water-conducting fracture zone; is the average Langmuir pressure parameter for carbon dioxide of the rock strata of the water-conducting fracture zone; is the density of the 1st, 2nd, and n-th rock strata in the fracture zone; is the adsorption volume constant of the 1st, 2nd, and n-th rock strata in the fracture zone; is the adsorption pressure constant of the 1st, 2nd, and n-th rock strata in the fracture zone.

8. The method of claim 6, wherein, The simplified formula is obtained by substituting the simplified formula into the initial model of the total carbon storage of the whole abandoned mine with high water flowing fractured zone; The simplified formula is determined based on the geometric parameters of the abandoned mine.

9. The method of estimating abandoned mine carbon storage according to claim 8, wherein, The simplified formula is: ； The total carbon storage model of the whole abandoned mine is: 。 10. A computer device comprising: A memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the abandoned mine carbon storage estimation method of any one of claims 1-9.

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