Design and construction method of steeply inclined coal seam underground reservoir
By utilizing convective transport roadways to create water storage space within steeply inclined coal seams, and combining this with seepage prevention measures and artificial dams, the construction challenges of underground reservoirs in steeply inclined coal seams have been solved, achieving low-cost, high-efficiency water storage and enhanced safety.
Patent Information
- Application Number
- CN202410644618.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-23
- Publication Date
- 2025-11-25
Smart Images
Figure CN121007031A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of coal mine underground reservoir, and particularly relates to a construction method of an underground reservoir in an acute-inclined coal seam. BACKGROUND
[0002] At present, for the mining conditions of the overlying bedrock in the ecologically fragile area in the upper reaches of the Yellow River, the water-conducting fractured zone formed by large-scale mining of the coal seam can directly penetrate the surface, water-preservation mining cannot protect the aquifer from the influence of mining, and a large amount of coal resources cannot be abandoned, but only the underground water in the overlying aquifer can be transferred to a suitable water storage space to form a coal mine underground reservoir to maintain the development and utilization value of water resources. The coal mine underground reservoir is to form a water storage space by constructing an underground dam in the goaf and to realize safe production of the mine and protection and utilization of underground water resources by artificial regulation and storage. At present, the research on the coal mine underground reservoir is mainly applicable to the flat area of the water storage roadway in the coal seam with a small inclination (for example, the coal seam inclination < 25°), and the construction method is difficult to be directly applied to the construction of the underground reservoir in the acute-inclined coal seam (the coal seam inclination > 45°).
[0003] Specifically, the traditional horizontal coal seam mining is mainly carried out in a large-scale fully-mechanized way, the goaf has a large area, and part of the coal pillars around the goaf are reserved to support the overlying roof pressure and the weight of the rock stratum. When the coal mine underground reservoir is constructed, the artificial dam formed by concrete pouring connects the support coal pillars to form the coal mine underground reservoir. However, in the mining process of the acute-inclined coal seam, the roof and the floor are both coal seams, and the texture is softer than that of the rock stratum, which can be deformed more greatly in the mining disturbance. SUMMARY
[0004] The present application solves the technical problem that the construction method of the existing coal mine underground reservoir is not applicable to the construction of the underground reservoir in the acute-inclined coal seam. Therefore, the present application provides a construction and design method applicable to the construction of the underground reservoir in the acute-inclined coal seam.
[0005] In view of the above technical problems, the present application provides the following technical solutions:
[0006] A construction method of an underground reservoir in an acute-inclined coal seam, comprising:
[0007] Two first transport roadways and a second transport roadway extending in the same direction in the same coal seam are taken as the main water storage space of the underground reservoir, and the inner walls of the first transport roadways and the second transport roadway are subjected to impermeable treatment;
[0008] A connecting roadway is constructed, and the two ends of the connecting roadway are connected with the first transport roadway and the second transport roadway respectively;
[0009] A water pumping station is constructed, one end of which is connected to the first transport roadway and the other end is connected to the water inlet pipe. The water pumping station is equipped with a suction pump for inputting mine water into the underground reservoir.
[0010] Artificial dams were constructed at both ends of the first and second transport tunnels to contain the water, and an outlet pipe for drainage was constructed on the artificial dam in the second transport tunnel.
[0011] In some embodiments of the present invention, gas extraction is performed in the first transport roadway, the second transport roadway, and the connecting roadway.
[0012] In some embodiments of the present invention, alarm devices and monitoring devices are installed in the first transport roadway, the second transport roadway, and the connecting roadway.
[0013] In some embodiments of the present invention, connecting pipelines for connecting with underground reservoirs of other coal seams are constructed on the first transport roadway and / or the second transport roadway.
[0014] In some embodiments of the present invention, the roof walls of the first transport roadway and the second transport roadway are supported.
[0015] This invention also provides a design method for a steeply inclined coal seam underground water reservoir, comprising:
[0016] S1. Collect stratigraphic information of the proposed underground reservoir area;
[0017] S2. Drill core samples from the strata in the proposed underground reservoir area to obtain basic formation mechanical parameters and permeability;
[0018] S3. Based on the stratigraphic information of the proposed underground reservoir area, as well as the basic mechanical parameters and permeability of the stratigraphic strata, the depth and location of the proposed underground reservoir in the steeply dipping coal seam are selected.
[0019] S4. Excavate the coal seam and construct an underground reservoir, using the transport roadway as the main water storage space.
[0020] In some embodiments of the present invention, collecting stratigraphic information of the proposed underground reservoir area includes: collecting the elevation, dip angle, strike, and dip parameters of the coal seam in the proposed underground reservoir area, as well as the lithology and thickness of the top and bottom plates.
[0021] In some embodiments of the present invention, drilling core samples from the strata in the area of the proposed underground reservoir to obtain basic formation mechanical parameters and permeability includes:
[0022] By drilling geological or hydrological boreholes, core samples of steeply inclined coal seams are obtained from top to bottom. Basic mechanical parameters and permeability of the formation are obtained by conducting uniaxial mechanical experiments, triaxial mechanical experiments, and permeability tests on the core samples.
[0023] In some embodiments of the present application, according to the stratum information and the basic mechanical parameters and the permeability of the stratum in the region where the underground reservoir is to be built, the depth and the position of the underground reservoir in the steeply inclined coal seam are determined, including:
[0024] According to the basic mechanical parameters of the stratum, the mechanical response characteristics of the region where the underground reservoir is to be built are obtained, and the stress concentration of the region where the underground reservoir is built is determined; when the maximum compressive stress is less than the compressive strength of the coal and rock and the maximum tensile stress is less than the tensile strength of the coal and rock, it is determined that the region where the underground reservoir is to be built meets the construction requirements, so as to obtain the depth and the position of the underground reservoir in the steeply inclined coal seam.
[0025] In some embodiments of the present application, before the underground reservoir is built, the design method further includes estimating the water storage capacity of the region where the underground reservoir is to be built.
[0026] The technical solution of the present application has the following technical effects compared with the prior art:
[0027] In the construction method of the underground reservoir in the steeply inclined coal seam provided by the present application, two first transport roadways and two second transport roadways extending in the same direction in the same coal seam are used as the main water storage space of the underground reservoir, and the connecting roadway, the water pumping station and the artificial dam for surrounding the water body are built on the basis of the anti-seepage treatment of the main water storage space, so as to form the final underground reservoir in the coal mine, which is particularly suitable for the construction of the underground reservoir in the steeply inclined coal seam with an inclination greater than 45°. At the same time, compared with the traditional construction of the underground reservoir in the coal mine which needs to build a large number of artificial dams as the main water retaining body of the water storage building, the method only needs to build two artificial dams at the water inlet and outlet of the water transport roadway, so the construction cost is low. The method can effectively ensure the water storage and water retention capacity of the underground reservoir in the steeply inclined coal seam in the coal mine, and improve the safety of the construction of the underground reservoir in the steeply inclined coal seam in the coal mine. BRIEF DESCRIPTION OF DRAWINGS
[0028] The preferred embodiments of the present application will be described in detail below with the help of the accompanying drawings, which will help to understand the purposes and advantages of the present application, in which:
[0029] Figure 1 The structure schematic diagram of the multi-layer underground reservoir built in the steeply inclined coal seam according to the present application;
[0030] Figure 2 The structure schematic diagram of a specific embodiment of the underground reservoir in the steeply inclined coal seam according to the present application;
[0031] Figure 3 The flow chart of the design method of the underground reservoir in the steeply inclined coal seam according to the present application. DETAILED DESCRIPTION
[0032] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.
[0033] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0034] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0035] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict between them.
[0036] The following is a specific embodiment of the design method of the steeply inclined coal seam underground reservoir provided by the present application, which is used to provide scientific guidance for the site selection and construction of the coal mine underground reservoir on the basis of the stratum and geological information analysis of the steeply inclined coal seam. As shown in the figure, it includes the following steps: Figure 3
[0037] S1. Collect stratum information of the area where the underground reservoir is to be built;
[0038] Specifically, collecting stratum information of the area where the underground reservoir is to be built includes collecting coal seam elevation, dip angle, strike, tendency parameters, roof and floor lithology and thickness of the area where the underground reservoir is to be built in the steeply inclined coal seam.
[0039] Further preliminarily judge whether the area where the coal mine underground reservoir is to be built is suitable for building the coal mine underground reservoir, and the criteria include but are not limited to the following points:
[0040] 1. The number of underground reservoirs above the coal mine underground reservoir to be built should be ≤1;
[0041] 2. The proposed coal mine underground reservoir area should not have obvious fault zones and tectonic fissure zones passing through;
[0042] 3. The proposed coal mine underground reservoir area should not have active or ongoing goaf above it. S2. Drill the stratum core of the proposed underground reservoir area to obtain the basic mechanical parameters and permeability of the stratum;
[0043] First, through geological drilling or hydrological drilling, drill the core of the steeply inclined coal seam from top to bottom, and the core range should include from the ground to 50m below the proposed underground reservoir.
[0044] Then, through uniaxial mechanical test, triaxial mechanical test, and permeability test, obtain the basic mechanical parameters and permeability of the stratum. The basic mechanical parameters of the stratum include: bulk density, uniaxial compressive strength, triaxial compressive strength, elastic modulus, Poisson's ratio, tensile strength, and other parameters of coal and roof and floor rocks.
[0045] Further determine whether the basic mechanical parameters and permeability of the stratum in the proposed underground reservoir area meet the construction requirements of the coal mine underground reservoir: the compressive strength of the coal and rock sample in the proposed coal mine underground reservoir area should be greater than 20MPa, if necessary, further measures such as anchor rod, anchor cable, and flexible shield support should be taken to reinforce the top and bottom of the water storage space to prevent roof collapse; at the same time, the permeability of the coal and rock floor drilling sample should be less than 1*10 -18 m 2 , otherwise grouting reinforcement and anti-seepage measures must be taken.
[0046] S3. According to the stratum information and the basic mechanical parameters and permeability of the stratum in the proposed underground reservoir area, select the depth and location of the steeply inclined coal seam proposed underground reservoir;
[0047] Bring the basic mechanical parameters of the stratum in the above area into numerical calculation software (such as Flac3D, Ansys), etc., to obtain the stress and strain cloud map of the proposed underground reservoir area after construction, obtain the mechanical response characteristics of the proposed underground reservoir area, and judge the stress concentration situation of the constructed underground reservoir area. When the numerical calculation encounters the following three situations, it is not recommended to build an underground reservoir here, and another area can be considered for the construction of a coal mine underground reservoir, or the form of the coal mine underground reservoir can be modified:
[0048] 1. If the maximum compressive stress calculated is greater than the coal and rock compressive strength index, i.e. , then the coal mine underground reservoir is not recommended to be built here, where: is the maximum compressive stress of the proposed coal mine underground reservoir after construction, which can be obtained by finite element numerical simulation calculation; is the uniaxial compressive strength of the coal and rock of the coal mine underground reservoir, which can be obtained by uniaxial test to determine the maximum stress. In addition, if the maximum compressive stress of the coal mine underground reservoir is When the maximum tensile stress is greater than 20 MPa, it is not recommended to build the underground reservoir at this location.
[0049] 2. If the calculated maximum tensile stress is greater than the tensile strength index of the coal rock, that is, then the underground reservoir is not recommended to be built at this location, wherein: is the maximum tensile stress of the coal mine underground reservoir after being built, which can be obtained by finite element numerical simulation calculation; is the uniaxial tensile strength of the coal rock of the coal mine underground reservoir, which can be determined by obtaining the maximum tensile strength through the Brazilian split test, or if it is not convenient to carry out such an experiment, the uniaxial tensile strength of the coal rock can be taken as 1 / 20 of the uniaxial compressive strength.
[0050] 3. If the calculated result is too large to cause numerical calculation to fail to converge, or the calculated local tensile strain is greater than 320 μ, or the calculated local compressive strain is greater than 400 μ, it is not recommended to build the coal mine underground reservoir at this location.
[0051] When judging the stress concentration of the built underground reservoir area, the numerical calculation software can be appropriately added with measures such as anchor, anchor cable, flexible shield support, and sprayed concrete, and after the support is completed, further numerical simulation calculation is carried out to check whether the maximum tensile / compressive stress, tensile / compressive strain meet the above rules, and whether the numerical simulation calculation can complete the convergence.
[0052] When the maximum compressive stress calculated according to the mechanical response characteristics is less than the compressive strength of the coal rock, and the maximum tensile stress is less than the tensile strength index of the coal rock, it is determined that the area of the proposed underground reservoir meets the construction requirements, and the location and depth of the proposed underground reservoir area can be obtained.
[0053] S4. Excavating the coal seam and using the transportation roadway as the main storage space of the underground reservoir to build the underground reservoir.
[0054] Specifically, after the depth and specific location of the proposed underground reservoir are determined, the coal mine transportation roadway in the coal seam where the proposed underground reservoir is located is excavated, and the transportation roadway used for mining is used as the main storage space of the underground reservoir to build the underground reservoir.
[0055] Meanwhile, before building the underground reservoir, the design method further includes step S5: estimating the water storage capacity of the proposed underground reservoir area. Specifically, the net space size of the proposed underground reservoir area in the steeply inclined coal seam can be obtained by counting the contour lines of the coal mine underground reservoir floor in the steeply inclined coal seam.
[0056] After the location of the coal mine underground reservoir is selected according to the above coal mine underground reservoir design method and the coal mining work is completed, the construction step of the coal mine underground reservoir can be carried out; the present application also provides a specific implementation mode of the construction method of the above underground reservoir in the steeply inclined coal seam, which comprises:
[0057] As shown in Figure 1 , Figure 2 , two first transport roadways 10 and second transport roadways 20 in the same coal seam are taken as the main water storage space of the underground reservoir, and the inner walls of the first transport roadways 10 and the second transport roadways 20 are subjected to impermeable treatment. Specifically, the impermeable treatment is achieved by pouring impermeable materials such as marithrough the inner walls of the first transport roadways 10 and the second transport roadways 20. Further, steel frames are installed on the top walls of the first transport roadways 10 and the second transport roadways 20 for support treatment.
[0058] A connecting roadway 30 is built, and the two ends of the connecting roadway 30 are connected with the first transport roadways 10 and the second transport roadways 20, respectively.
[0059] A water pumping station 40 is built, one end of which is connected with the first transport roadways 10, and the other end is connected with an input pipeline 60 for water intake. The water pumping station 40 is provided with a suction pump (not shown in the figure), and is used for receiving mine water such as goaf water and gushing water in the mining area, and for filtering the input water source of the underground reservoir to remove impurities such as coal slime and gangue. The suction pump is used for pumping the filtered water into the first transport roadways 10.
[0060] Artificial dam bodies 50 are built at the two ends of the first transport roadways 10 and the second transport roadways 20, respectively, to enclose the water body, and an output pipeline 70 for water drainage is built on the artificial dam body 50 of the second transport roadways 20. Specifically, the artificial dam body 50 is made of concrete with a strength of C25 or above, and the artificial dam body 50 blocks the first transport roadways 10 and the second transport roadways 20 to form a closed water storage space. The output pipeline 70 is mainly used for transporting mine water to the mining area, and is connected with a ground or underground mine water treatment plant, and is used as domestic water, production water and industrial water after filtration.
[0061] The impermeable treatment of the first transport roadways 10 and the second transport roadways 20, the building of the connecting roadway 30 and the building of the water pumping station 40 can be performed in any order or simultaneously to improve the construction efficiency.
[0062] In an optional embodiment, before the underground reservoir is used for water storage, the first transport roadways 10, the second transport roadways 20 and the connecting roadway 30 are subjected to gas suction treatment to ensure that the gas content is within a safe value range.
[0063] In an optional embodiment, alarm devices and monitoring devices are installed in the first transport roadways 10, the second transport roadways 20 and the connecting roadway 30. Specifically, the alarm devices include but are not limited to gas over-limit alarm devices, and the monitoring devices include but are not limited to reservoir stress, strain and osmotic pressure monitoring devices.
[0064] The communication pipe 80 for communicating with the underground reservoir of other coal seams is built on the first transport roadway 10 and / or the second transport roadway 20. Specifically, Figure 1 The white box parts arranged in the middle, upper and lower positions are the layout positions of the multi-layer goaf during the mining of the steeply inclined coal seam. The blank parts of the same coal seam are the layout positions of the transport roadway of each layer goaf. The communication pipe 80 is arranged between the transport roadways of the upper and lower layers for communicating the upper and lower underground reservoirs. The multi-layer underground reservoir is usually built from the upper to the lower. After the reservoir body of the upper underground reservoir (i.e. the first transport roadway 10 and the second transport roadway 20) is built, a borehole is drilled in the bottom of one of the transport roadways until the transport roadway of the lower coal seam is communicated. The communication pipe is arranged in the borehole and the gap between the end of the communication pipe and the borehole is blocked by the impermeable material to realize the communication of the upper and lower underground reservoirs.
[0065] Obviously, the above embodiments are only examples for clearly illustrating the present application, but not the limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be exhausted. The obvious changes or variations derived from the above still fall into the protection scope of the present application.
Claims
1. A method for constructing an underground reservoir of steeply inclined coal seams, characterized in that, The application relates to a method for building an underground reservoir in an acute-inclined coal seam. The two first transportation roadways and the second transportation roadway in the same coal seam are used as the main water storage space of the underground reservoir, and the inner walls of the first transportation roadways and the second transportation roadway are subjected to anti-seepage treatment; A connecting roadway is built, and the two ends of the connecting roadway are connected with the first transportation roadway and the second transportation roadway respectively; A water delivery pump house is built, one end of the water delivery pump house is connected with the first transportation roadway, the other end of the water delivery pump house is connected with a water inlet pipeline, and a suction pump for inputting mine water into the underground reservoir is arranged in the water delivery pump house; Artificial dam bodies are built at the two ends of the first transportation roadway and the second transportation roadway to enclose water bodies, and an output pipeline for draining water is built on the artificial dam body of the second transportation roadway.
2. The method for constructing an underground reservoir in steeply inclined coal seam according to claim 1, characterized in that, Gas suction treatment is conducted in the first transportation roadway, the second transportation roadway and the connecting roadway.
3. The method of constructing an underground reservoir in a steeply inclined coal seam according to claim 1, wherein, Alarm devices and monitoring devices are installed in the first transportation roadway, the second transportation roadway and the connecting roadway.
4. The method of constructing an underground reservoir in a steeply inclined coal seam according to claim 1, wherein, A connecting pipeline for connecting with underground reservoirs in other coal seams is built on the first transportation roadway and / or the second transportation roadway.
5. The method of constructing an underground reservoir for steeply inclined coal seams according to claim 1, wherein, The top walls of the first transportation roadway and the second transportation roadway are subjected to support treatment.
6. A method for designing an underground reservoir of steeply inclined coal seam, characterized in that, The application relates to a method for building an underground reservoir in an acute-inclined coal seam. S1. Collecting stratum information of a region where an underground reservoir is to be built; S2. Drilling stratum cores of the region where the underground reservoir is to be built to obtain basic mechanical parameters and permeability of the stratum; S3. Selecting the depth and position of the underground reservoir in the acute-inclined coal seam according to the stratum information of the region where the underground reservoir is to be built and the basic mechanical parameters and permeability of the stratum; S4. Excavating the coal seam and building the underground reservoir by taking the transportation roadway as the main water storage space of the underground reservoir.
7. The method of designing an underground reservoir for steeply inclined coal seams according to claim 6, characterised in that, Collecting the stratum information of the region where the underground reservoir is to be built includes collecting the parameters of the coal seam elevation, inclination, strike, tendency, roof and floor lithology and thickness of the region where the underground reservoir is to be built in the acute-inclined coal seam.
8. The method of designing an underground reservoir for steeply inclined coal seams according to claim 6, characterised in that, Drilling the stratum cores of the region where the underground reservoir is to be built to obtain the basic mechanical parameters and permeability of the stratum includes: The stratum cores of the acute-inclined coal seam are obtained from top to bottom through geological drilling or hydrological drilling, and the basic mechanical parameters and permeability of the stratum are obtained by conducting uniaxial mechanical experiments, triaxial mechanical experiments and permeability tests on the stratum cores.
9. The method of designing an underground reservoir for steeply inclined coal seams according to claim 6, wherein, Selecting the depth and position of the underground reservoir in the acute-inclined coal seam according to the stratum information of the region where the underground reservoir is to be built and the basic mechanical parameters and permeability of the stratum includes: The mechanical response characteristics of the region where the underground reservoir is to be built are obtained according to the basic mechanical parameters of the stratum, and stress concentration of the region where the underground reservoir is to be built is judged; when the maximum compressive stress is less than the compressive strength of the coal rock and the maximum tensile stress is less than the tensile strength of the coal rock, it is confirmed that the region where the underground reservoir is to be built meets the building requirements, so that the depth and position of the underground reservoir in the acute-inclined coal seam are obtained.
10. The method of designing an underground reservoir for steeply inclined coal seams according to claim 6, wherein, Before the underground reservoir is built, the design method further includes estimating the water storage capacity of the region where the underground reservoir is to be built.