Optimal selection method for geological storage position of water depth part of mine

Abstract

The invention discloses an optimal selection method for a geological storage position of a water depth part of a mine. The optimal selection method comprises the following steps: S1, basic geological exploration; s2, stratum parameters are collected; s3, reservoir physical property analysis; s4, safety and environmental protection comprehensive evaluation. According to the method, the principle is scientific, operation is easy, the sand-mud ratio, the porosity and the permeability are calculated through the well logging calculation model, the sealing target layer with the high sand-mud ratio, the large porosity and the high permeability is optimized according to the sand-mud ratio, the porosity and the permeability, and the method has high safety, saves energy, is environmentally friendly and is high in water storage efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of mine water treatment and geological storage, and in particular relates to an optimization method for deep geological storage layers of mine water. Background Art

[0002] Mine water is an industrial wastewater. With the advancement of technology, deep underground injection and storage has become an important method for disposing of industrial wastewater. Similarly, injecting mine water into deep strata for storage is an efficient and economical mine water treatment technology. Existing mine water storage technologies mostly focus on the design of deep storage wells, with less research on the selection of mine water storage layers. Current mine water storage technologies suffer from imperfect storage layer selection methods and unclear processes. Furthermore, they fail to establish a multi-dimensional comprehensive evaluation system that comprehensively considers safety, environmental protection, and water storage efficiency. Summary of the Invention

[0003] The purpose of the present invention is to provide a safe, environmentally friendly and highly efficient method for optimizing the geological sealing of deep mine water layers.

[0004] To achieve the above object, the present invention adopts the following technical solution: a method for optimizing the deep geological sealing layer of mine water, comprising the following steps:

[0005] S1. Basic geological survey;

[0006] S2, formation parameter collection;

[0007] S3, reservoir physical property analysis;

[0008] S4. Comprehensive assessment of safety and environmental protection.

[0009] The specific contents of step S1 are as follows: collecting basic geological data, including regional geological data, hydrogeological data and mine development and construction plans, identifying the basic geological overview and hydrogeological conditions around the mine, clarifying the structural divisions, the development of faults and folds, and the frequency and intensity of crustal activity; and prioritizing areas with stable basin basement development, few faults, and infrequent crustal activity.

[0010] The specific content of step S2 is: collecting logging data of drilling in the area determined by S1 and obtaining a stratigraphic histogram; in order to ensure that the mine water is stably and safely sealed in deep strata, it is preferred to use a sandstone reservoir with a burial depth greater than the coal mining depth and a thick stratum, and the overlying and underlying strata of the reservoir have relatively stable impermeable layers or buffer layers.

[0011] The specific content of step S3 is: collecting logging data in the area, using the logging calculation model to calculate the sand-mud ratio, porosity and permeability, and selecting the target storage layer with high sand-mud ratio, large porosity and high permeability based on the sand-mud ratio, porosity and permeability.

[0012] The specific content of step S4 is: by comparing the hydrogeological conditions of the regional strata, excluding those strata that have hydraulic connections with the coal mining area and the aquifers with utilization value, and selecting the target sealing storage layer that has no impact on coal mining safety and no pollution to the environment.

[0013] In step S3, the sand-mud ratio is calculated using the natural gamma curve of well logging to calculate the mud content. The calculation formula is:

[0014] Sand-mud ratio = (1-SH) / SH

[0015] Where:

[0016] GR is the logging value selected for calculating the shale content;

[0017] GRmin is the logging value for pure sandstone formation;

[0018] GRmax is the logging value for pure mudstone formation;

[0019] GCUR is the empirical coefficient used to calculate the mud content.

[0020] The calculation formula of porosity POR in step S3 is as follows:

[0021]

[0022] in:

[0023]

[0024] Where:

[0025] TC is the acoustic transit time after compaction correction;

[0026] The skeleton value of TM acoustic time difference is usually 54μs / ft for sandstone;

[0027] The fluid value of TF acoustic wave time difference is usually 189μs / ft;

[0028] CNL is the neutron-compensated logging value;

[0029] PRM is the neutron-compensated skeleton value, and -4% is usually selected for sandstone;

[0030] PNF is the fluid value for compensating neutrons, and 100% is usually selected for sandstone;

[0031] DEN is the well logging value of density;

[0032] DM is the skeleton value of density, and 2.65g / cm is usually selected for sandstone 3 ;

[0033] DF is the fluid density value, usually 1.00g / cm 3 ;

[0034] SH is the mud content;

[0035] TSH, NSH, and DSH are the sonic time difference, compensated neutron, and density values of mudstone, respectively.

[0036] In step S3, the permeability PERM is calculated using the following formula:

[0037]

[0038] Where: PORT represents the total porosity and SIRR represents the irreducible water saturation.

[0039] Adopting the above technical scheme, the preferred method of the present invention adopts the following four steps: screening structurally stable areas through basic geological survey; preliminarily selecting target layers based on logging data, and calculating reservoir physical property parameters based on logging data; and determining target layers through safety and environmental protection assessment principles.

[0040] The criteria for determining a tectonic stable area include: no active tectonic belt in the basin, being in a non-seismic active zone, being more than 500 meters away from the nearest fault, and having a continuous mudstone layer with a thickness of more than 20 meters in the overlying / underlying strata.

[0041] The logging data and screening conditions include: the target layer is buried deeper than the coal mining depth, the target layer is mainly sandstone with great thickness, and both the overlying and underlying strata of the reservoir have relatively stable impermeable layers or buffer layers (such as gypsum mudstone, etc.).

[0042] Reservoir physical parameters and standards are: sand-mud ratio, porosity, and permeability. In deep geological storage of mine water, due to the use of pressurized water injection, the sand-mud ratio is a more critical indicator affecting the water injection effect than porosity and permeability. The sand-mud ratio is preferably greater than 6.

[0043] The principles of safety and environmental assessment include: comparing the hydrogeological conditions of regional strata, excluding strata that are hydraulically connected to coal mining areas and valuable aquifers, and selecting target reservoirs that have no impact on coal mining safety and no pollution to the environment.

[0044] In summary, the present invention has a scientific principle and is easy to operate. By calculating the sand-mud ratio, porosity and permeability, the target layer for mine water storage can be optimized. It has high safety, energy saving and environmental protection, and high water storage efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0046] like Figure 1 As shown, a preferred method of deep geological sealing layer of mine water of the present invention comprises the following steps:

[0047] S1. Basic geological survey;

[0048] S2, formation parameter collection;

[0049] S3, reservoir physical property analysis;

[0050] S4. Comprehensive assessment of safety and environmental protection.

[0051] The specific contents of step S1 are as follows: collecting basic geological data, including regional geological data, hydrogeological data and mine development and construction plans, identifying the basic geological overview and hydrogeological conditions around the mine, clarifying the structural divisions, the development of faults and folds, and the frequency and intensity of crustal activity; and prioritizing areas with stable basin basement development, few faults, and infrequent crustal activity.

[0052] The specific content of step S2 is: collecting logging data of drilling in the area determined by S1 and obtaining a stratigraphic histogram; in order to ensure that the mine water is stably and safely sealed in deep strata, it is preferred to use a sandstone reservoir with a burial depth greater than the coal mining depth and a thick stratum, and the overlying and underlying strata of the reservoir have relatively stable impermeable layers or buffer layers.

[0053] The specific content of step S3 is: collecting logging data in the area, using the logging calculation model to calculate the sand-mud ratio, porosity and permeability, and selecting the target storage layer with high sand-mud ratio, large porosity and high permeability based on the sand-mud ratio, porosity and permeability.

[0054] The specific content of step S4 is: by comparing the hydrogeological conditions of the regional strata, excluding those strata that have hydraulic connections with the coal mining area and the aquifers with utilization value, and selecting the target sealing storage layer that has no impact on coal mining safety and no pollution to the environment.

[0055] In step S3, the sand-mud ratio is calculated using the natural gamma curve of well logging to calculate the mud content. The calculation formula is:

[0056]

[0057] Sand-mud ratio = (1-SH) / SH

[0058] Where:

[0059] GR is the logging value selected for calculating the shale content;

[0060] GRmin is the logging value for pure sandstone formation;

[0061] GRmax is the logging value for pure mudstone formation;

[0062] GCUR is the empirical coefficient used to calculate the mud content.

[0063] The calculation formula of porosity POR in step S3 is as follows:

[0064]

[0065] in:

[0066]

[0067] Where:

[0068] TC is the acoustic transit time after compaction correction;

[0069] The skeleton value of TM acoustic time difference is usually 54μs / ft for sandstone;

[0070] The fluid value of TF acoustic wave time difference is usually 189μs / ft;

[0071] CNL is the neutron-compensated logging value;

[0072] PRM is the neutron-compensated skeleton value, and -4% is usually selected for sandstone;

[0073] PNF is the fluid value for compensating neutrons, and 100% is usually selected for sandstone;

[0074] DEN is the well logging value of density;

[0075] DM is the skeleton value of density, and 2.65g / cm is usually selected for sandstone 3 ;

[0076] DF is the fluid density value, usually 1.00g / cm 3 ;

[0077] SH is the mud content;

[0078] TSH, NSH, and DSH are the sonic time difference, compensated neutron, and density values of mudstone, respectively.

[0079] In step S3, the permeability PERM is calculated using the following formula:

[0080]

[0081] Where: PORT represents the total porosity and SIRR represents the irreducible water saturation.

[0082] Taking a coal mine in the Yuheng mining area of the Ordos Basin as an example, the Liujiagou Formation rock layer of the Lower Triassic System selected by the above method and steps has a sand-mud ratio of 8.0, a porosity of 2.4%, and a permeability of 0.013×10-3μm. 2It is 1,559 meters vertically away from the mining layer and is overlain by the Ermaying Formation, Yanchang Formation mudstone and oil shale aquicludes.

[0083] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for optimizing the deep geological storage layer of mine water, characterized by: The following steps are involved: S1. Basic geological survey; S2, formation parameter collection; S3, reservoir physical property analysis; S4. Comprehensive assessment of safety and environmental protection.

2. The method for optimizing the deep geological storage layer of mine water according to claim 1, characterized in that: The specific contents of step S1 are as follows: collecting basic geological data, including regional geological data, hydrogeological data and mine development and construction plans, identifying the basic geological overview and hydrogeological conditions around the mine, clarifying the structural divisions, the development of faults and folds, and the frequency and intensity of crustal activity; and prioritizing areas with stable basin basement development, few faults, and infrequent crustal activity.

3. The method for optimizing the deep geological storage layer of mine water according to claim 1, characterized in that: The specific content of step S2 is: collecting logging data of drilling in the area determined by S1 and obtaining a stratigraphic histogram; in order to ensure that the mine water is stably and safely sealed in deep strata, it is preferred to use a sandstone reservoir with a burial depth greater than the coal mining depth and a thick stratum, and the overlying and underlying strata of the reservoir have relatively stable impermeable layers or buffer layers.

4. The method for optimizing the deep geological storage layer of mine water according to claim 1, characterized in that: The specific content of step S3 is: collecting logging data in the area, using the logging calculation model to calculate the sand-mud ratio, porosity and permeability, and selecting the target storage layer with high sand-mud ratio, large porosity and high permeability based on the sand-mud ratio, porosity and permeability.

5. The method for optimizing the deep geological storage layer of mine water according to claim 1, characterized in that: The specific content of step S4 is: by comparing the hydrogeological conditions of the regional strata, excluding those strata that have hydraulic connections with the coal mining area and the aquifers with utilization value, and selecting the target sealing storage layer that has no impact on coal mining safety and no pollution to the environment.

6. The method for optimizing the deep geological storage layer of mine water according to claim 4, characterized in that: In step S3, the sand-mud ratio is calculated using the natural gamma curve of well logging to calculate the mud content. The calculation formula is: Sand-mud ratio = (1-SH) / SH Where: GR is the logging value selected for calculating the shale content; GRmin is the logging value for pure sandstone formation; GRmax is the logging value for pure mudstone formation; GCUR is the empirical coefficient used to calculate the mud content.

7. The method for optimizing the deep geological storage layer of mine water according to claim 4, characterized in that: The calculation formula of porosity POR in step S3 is as follows: in: Where: TC is the acoustic transit time after compaction correction; The skeleton value of TM acoustic time difference is usually 54μs / ft for sandstone; The fluid value of TF acoustic wave time difference is usually 189μs / ft; CNL is the neutron-compensated logging value; PRM is the neutron-compensated skeleton value, and -4% is usually selected for sandstone; PNF is the fluid value for compensating neutrons, and 100% is usually selected for sandstone; DEN is the well logging value of density; DM is the skeleton value of density, and 2.65g / cm is usually selected for sandstone 3 ; DF is the fluid density value, usually 1.00g / cm 3 ; SH is the mud content; TSH, NSH, and DSH are the sonic time difference, compensated neutron, and density values of mudstone, respectively.

8. The method for optimizing the deep geological storage layer of mine water according to claim 4, characterized in that: In step S3, the permeability PERM is calculated using the following formula: Where: PORT represents the total porosity and SIRR represents the irreducible water saturation.

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