Coal mine ground pumping and draining separation water energy storage method

Abstract

The invention provides a coal mine ground pumping and draining separation layer water energy storage method. The method comprises the steps that the water-rich strength of a mining separation layer zone in a coal mining area is judged; when the water-rich strength of the mining separation zone reaches the preset strength, an upper reservoir and a lower reservoir are built on the ground with a preset distance from the coal mining area; water in the mining separation zone is pumped and drained to the lower reservoir, when the power grid is in the valley period, the water in the lower reservoir is pumped to the upper reservoir so as to convert electric energy of the power grid into potential energy of the water, and when the power grid is in the peak period, the water in the upper reservoir is released to the lower reservoir so as to convert the potential energy of the water into the electric energy of the power grid; and after mining of the coal mining area is completed, water of the upper reservoir and the lower reservoir is recharged to the mining separation zone. According to the energy storage method for pumping and draining the separation water on the ground of the coal mine, groundwater resources in the mining separation zone are fully utilized, and recharge after mining is completed is matched, so that waste of the groundwater resources is effectively reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of mine water prevention, control and utilization, and in particular to a method for pumping out layer water from the surface of a coal mine and storing energy. Background Art

[0002] After mining the extra-thick coal seams in the Yonglong mining area of the Huanglong Jurassic coalfield, multi-layer fissure-cavity detachments are formed. The detachment space volume is large, and the pores and fissures of the Luohe Formation aquifer increase after mining. The water-richness of the aquifer is significantly enhanced after mining. Due to the recharge of the highly water-rich aquifer, the permeability coefficient of the detachment zone increases by 2 orders of magnitude, and the unit water inflow increases by 1 order of magnitude.

[0003] To prevent water inrush from abscission layers during mining, large-diameter surface boreholes are used for drainage. Typically, dozens of drainage holes are drilled on a single working face. However, due to the high water content of the aquifers and abscission layers after mining, the drainage volume of a single borehole can reach nearly one million cubic meters. Groundwater and abscission water resources are inefficient after mining in extremely thick coal seams. Most of this water is directly discharged after surface or underground drainage, leading to significant waste of groundwater resources. Summary of the Invention

[0004] The present disclosure aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, the purpose of the present disclosure is to provide a method for storing energy by pumping out layer water from the ground in a coal mine.

[0006] To achieve the above-mentioned purpose, the present disclosure provides a method for pumping water from the mining layer and storing energy on the ground of a coal mine, comprising: judging the water-rich intensity of the mining separation zone in the coal mining area, wherein the mining separation zone is located in the rock layer between the coal seam and the topsoil layer in the coal mining area; when the water-rich intensity of the mining separation zone reaches a preset intensity, constructing an upper reservoir and a lower reservoir on the ground at a preset distance from the coal mining area, wherein the height of the upper reservoir is greater than the height of the lower reservoir; pumping the water in the mining separation zone to the lower reservoir, and, when the power grid is in a valley period, pumping the water in the lower reservoir to the upper reservoir to convert the electrical energy of the power grid into the potential energy of water, and when the power grid is in a peak period, releasing the water in the upper reservoir to the lower reservoir to convert the potential energy of water into the electrical energy of the power grid; after mining of the coal mining area is completed, recharging the water in the upper reservoir and the lower reservoir to the mining separation zone.

[0007] Optionally, the method also includes: judging the unit water yield, permeability coefficient and single-hole pumping flow in the water-rich intensity of the mining detachment zone; when the unit water yield of the mining detachment zone is not less than the preset unit water yield, the permeability coefficient of the mining detachment zone is not less than the first preset multiple of the pre-mining permeability coefficient, and the single-hole pumping flow of the mining detachment zone is not less than the preset single-hole pumping flow, it is determined that the water-rich intensity of the mining detachment zone has reached the preset intensity.

[0008] Optionally, the method further includes: constructing a lower reservoir with a capacity not less than a second preset multiple of the expected drainage volume of the mining-induced detachment zone; wherein the capacity V1 of the lower reservoir is: V1=(A+B)hl / 2, A is the bottom width of the lower reservoir, B is the top width of the lower reservoir, h is the depth of the lower reservoir, and l is the length of the lower reservoir; the expected drainage volume Q of the mining-induced detachment zone is: The q i is the drainage volume per unit time of the ith borehole in the mining separation zone, and the t i is the effective utilization time of the i-th borehole in the mining separation zone.

[0009] Optionally, the method further includes: constructing the capacity of the upper warehouse to be no less than a third preset multiple of the capacity of the lower warehouse.

[0010] Optionally, the method further includes: when the coal seam is horizontal, controlling the horizontal distance between the upper reservoir and the coal mining area to be no less than L A , and / or, control the horizontal distance between the lower storage and the coal mining area to be no less than L A Among them, L A =L1+L2+W, W is the width of the retaining belt at the edge of the mining area; L1=H1 / tgφ, H1 is the thickness of the topsoil layer, φ is the movement angle of the topsoil layer; L2=H2 / tgγ, H2 is the vertical distance between the coal seam and the topsoil layer, γ is the strike movement angle of the rock stratum.

[0011] Optionally, the method further includes: when the coal seam is inclined and the upper reservoir is close to the top of the coal seam, controlling the horizontal distance between the upper reservoir and the coal mining area to be no less than L B , and / or, when the coal seam is inclined and the lower reservoir is close to the top of the coal seam, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L B Among them, L B=L1+L2+W, W is the width of the retaining belt at the edge of the mining area; L1=H1 / tgφ, H1 is the thickness of the topsoil layer, φ is the movement angle of the topsoil layer; L2=H2 / tgδ, H2 is the vertical distance between the coal seam and the topsoil layer, δ is the uphill movement angle of the rock layer.

[0012] Optionally, the method further includes: when the coal seam is inclined and the upper reservoir is close to the bottom of the coal seam, controlling the horizontal distance between the upper reservoir and the coal mining area to be no less than L C , and / or, when the coal seam is inclined and the lower reservoir is close to the bottom of the coal seam, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L C Among them, L C =L1+L2+W, W is the width of the retaining belt at the edge of the mining area; L1=H1 / tgφ, H1 is the thickness of the topsoil layer, φ is the movement angle of the topsoil layer; L2=H2 / tgβ, H2 is the vertical distance between the coal seam and the topsoil layer, β is the downhill movement angle of the rock layer.

[0013] Optionally, the method further includes: when the coal seam is inclined, the upper reservoir is close to the bottom of the coal seam, and the vertical distance between the coal seam and the topsoil layer is less than a preset vertical distance, controlling the horizontal distance between the upper reservoir and the coal mining area to be no less than L D , and / or, when the coal seam is inclined and the lower reservoir is close to the bottom of the coal seam, and the vertical distance between the coal seam and the topsoil layer is less than the preset vertical distance, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L D Among them, L D =L1+L2+L3+W; L3=(H s -H2) / tgα, the H s is a preset vertical spacing, and α is the inclination angle of the coal seam; The M is the coal mining thickness, and the a, b, c and d are different preset coefficients.

[0014] Optionally, the β is: β=δ-Kα, where δ is the uphill movement angle of the rock layer, α is the inclination angle of the coal seam, and K is a preset coefficient.

[0015] Optionally, the method further includes: constructing the upper reservoir and the lower reservoir in the valley on the ground, and performing anti-seepage treatment on the bottom and periphery of the upper reservoir and the lower reservoir when constructing the upper reservoir and the lower reservoir.

[0016] The technical solution provided by the present disclosure may have the following beneficial effects:

[0017] When the water-rich intensity of the mining-induced detachment zone reaches the preset intensity, the upper reservoir and the lower reservoir are built, and the height difference between the upper reservoir and the lower reservoir is used to realize pumped storage and water discharge for power generation. This can not only absorb the excess electricity during the valley period and alleviate the power consumption pressure during the peak period, but also realize the full utilization of the groundwater resources in the mining-induced detachment zone, and cooperate with the recharge after the mining is completed, thereby effectively reducing the waste of groundwater resources, thereby ensuring the protection and utilization of water resources while ensuring the safe production of the mine.

[0018] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present disclosure will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 This is a flow chart of a method for pumping stratum water from a coal mine surface for energy storage, according to one embodiment of the present disclosure;

[0021] Figure 2 This is a top view schematic diagram of a coal mine surface pumping and layer water storage method according to an embodiment of the present disclosure;

[0022] Figure 3 This is a cross-sectional schematic diagram (horizontally) of a coal mine surface pumping and stratum water energy storage method proposed in one embodiment of the present disclosure;

[0023] Figure 4 This is a cross-sectional schematic diagram of the coal mine surface pumping and stratum water energy storage proposed in one embodiment of the present disclosure (inclined and near the top);

[0024] Figure 5 This is a cross-sectional schematic diagram of a coal mine surface pumping and stratum water energy storage method proposed in one embodiment of the present disclosure (inclined and close to the bottom);

[0025] As shown in the figure: 1. Coal mining area, 2. Mining separation zone, 3. Coal seam, 4. Topsoil layer, 5. Lower reservoir, 6. Upper reservoir, 7. Pumping and drainage pipeline, 8. Pumping and drainage borehole. DETAILED DESCRIPTION

[0026] The following describes in detail embodiments of the present disclosure, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present disclosure and are not to be construed as limiting the present disclosure. On the contrary, the embodiments of the present disclosure include all variations, modifications, and equivalents that fall within the spirit and scope of the appended claims.

[0027] Mining of the extra-thick coal seam 3 easily leads to the formation of multiple layers of fissure-cavity separation, resulting in large separation spaces. Furthermore, mining of the Luohe Formation aquifer increases the number of pores and fissures, significantly increasing its water content and posing a significant threat to safe mine operation. Currently, large-diameter surface boreholes are used to pump out the post-mining separation water, resulting in a significant waste of groundwater resources.

[0028] like Figure 1 and Figure 2 As shown, the embodiment of the present disclosure proposes a method for storing energy by pumping out layer water from the surface of a coal mine, comprising:

[0029] S1: Determine the water-rich intensity of the mining separation zone 2 in the mining area 1, wherein the mining separation zone 2 is located in the rock layer between the coal seam 3 and the overburden layer 4 in the mining area 1;

[0030] S2: When the water-rich intensity of the mining separation zone 2 reaches a preset intensity, an upper reservoir 6 and a lower reservoir 5 are constructed on the ground at a preset distance from the mining area 1, wherein the height of the upper reservoir 6 is greater than that of the lower reservoir 5;

[0031] S3: Pump the water from the mining separation zone 2 to the lower reservoir 5. When the power grid is in the off-peak period, the water from the lower reservoir 5 is pumped to the upper reservoir 6 to convert the power grid's electrical energy into water potential energy. When the power grid is in the peak period, the water from the upper reservoir 6 is released to the lower reservoir 5 to convert the water potential energy into power grid electricity.

[0032] S4: After the mining of the coal mining area 1 is completed, the water in the upper reservoir 6 and the lower reservoir 5 is recharged into the mining separation zone 2.

[0033] It can be understood that when the water-rich intensity of the mining separation zone 2 reaches the preset intensity, the upper reservoir 6 and the lower reservoir 5 are constructed, and the height difference between the upper reservoir 6 and the lower reservoir 5 is used to realize pumped storage and water discharge for power generation. This can not only absorb the excess electricity during the valley period and alleviate the power consumption pressure during the peak period, but also realize the full utilization of the groundwater resources in the mining separation zone 2, and cooperate with the recharge after the mining is completed, thereby effectively reducing the waste of groundwater resources, thereby ensuring the protection and utilization of water resources while ensuring the safe production of the mine.

[0034] It should be noted that in the coal mining area 1, from bottom to top, there are coal seams 3, rock layers and topsoil layers 4, and the mining separation zone 2 refers to the cracks and pore spaces formed between different rock layers in the roof after the coal seam 3 is mined, and there are aquifers in the surrounding area to supply water to this space.

[0035] For pumping and draining water between the upper reservoir 6 and the lower reservoir 5, the machine room pump group can be used for pumping and storing energy, and the power station can be used for draining and generating electricity. The water in the mining detachment zone 2 can be pumped and drained to the lower reservoir 5. This means that the detachment water behind the working face goaf that affects the safe production in the front is pumped and drained to the lower reservoir 5 through the pumping and drainage borehole 8, the pumping and drainage pipeline 7, the submersible pump, etc.

[0036] In some embodiments, the method further comprises:

[0037] Determine the unit water yield, permeability coefficient and single-hole pumping flow rate in the water-rich intensity of the mining-induced separation zone 2;

[0038] When the unit water yield of the mining separation zone 2 is not less than the preset unit water yield, the permeability coefficient of the mining separation zone 2 is not less than the first preset multiple of the pre-mining permeability coefficient, and the single-hole pumping flow rate of the mining separation zone 2 is not less than the preset single-hole pumping flow rate, it is determined that the water-rich intensity of the mining separation zone 2 has reached the preset intensity.

[0039] It can be understood that the accurate judgment of the water-rich intensity of the mining-induced detachment zone 2 is ensured by comparing the unit water yield, permeability coefficient and single-hole pumping flow in the water-rich intensity of the mining-induced detachment zone 2 with the corresponding threshold values.

[0040] It should be noted that the preset unit water inflow, the first preset multiple and the preset single hole pumping flow rate can be set according to actual needs and are not limited to this. For example, the preset unit water inflow can be 0.1L / (s·m), the first preset multiple can be 5 times, and the preset single hole pumping flow rate can be 100m 3 / h.

[0041] That is to say, after the working face is mined, the unit water inflow in the abscission zone reaches 0.1L / (s·m) or more through the pumping test, and the permeability coefficient increases by 5 times or more compared with that before mining. At the same time, the single hole pumping reaches 100m 3 / h or above, it is determined that the water-rich intensity of the mining separation zone 2 has reached the preset intensity, so that subsequent pumped storage and water release for power generation can be carried out.

[0042] In some embodiments, the method further comprises:

[0043] The capacity of the lower reservoir 5 is constructed to be no less than the second preset multiple of the expected drainage volume of the mining separation zone 2;

[0044] Among them, the capacity V1 of the lower reservoir 5 is: V1=(A+B)hl / 2, A is the bottom width of the lower reservoir 5 (unit: m), B is the top width of the lower reservoir 5 (unit: m), h is the depth of the lower reservoir 5 (unit: m), and l is the length of the lower reservoir 5 (unit: m);

[0045] The expected drainage volume Q of the mining separation zone 2 is: q i is the drainage volume per unit time of the ith borehole in the mining-induced separation zone 2 (unit: m 3 / h), t i is the effective utilization time of the i-th borehole in the mining separation zone 2 (unit: h).

[0046] It can be understood that the capacity of the lower reservoir 5 is constructed to be no less than the second preset multiple of the expected drainage volume of the mining separation zone 2, thereby ensuring that the lower reservoir 5 can effectively accommodate and utilize the water resources in the mining separation zone 2.

[0047] It should be noted that the second preset multiple can be set according to actual needs and is not limited thereto. For example, the second preset multiple can be 1.2 times. In other words, the capacity of the lower reservoir 5 is constructed to be no less than 1.2 times the expected drainage volume of the mining separation zone 2.

[0048] In some embodiments, the method further includes: constructing a capacity of the upper reservoir 6 that is not less than a third preset multiple of the capacity of the lower reservoir 5 .

[0049] It can be understood that the capacity of the upper reservoir 6 is constructed to be no less than the third preset multiple of the capacity of the lower reservoir 5 , thereby ensuring that the upper reservoir 6 can effectively accommodate and utilize the water resources in the mining separation zone 2 .

[0050] It should be noted that the third preset multiple can be set according to actual needs and is not limited thereto. For example, the third preset multiple can be 1.5 times. In other words, the capacity V2 of the upper storage 6 is constructed to be no less than 1.5 times the capacity of the lower storage 5.

[0051] It can be expressed by the formula: V2≥1.5V1.

[0052] like Figure 3 As shown, in some embodiments, the method further includes:

[0053] When the coal seam 3 is horizontal, the horizontal distance between the upper reservoir 6 and the mining area 1 should be no less than L A , and / or, control the horizontal distance between the lower storage 5 and the coal mining area 1 to be no less than L A ;

[0054] Among them, L A =L1+L2+W, W is the width of the retaining belt at the edge of the mining area 1 (in meters);

[0055] L1 = H1 / tgφ, H1 is the thickness of the topsoil layer 4 (in m), φ is the movement angle of the topsoil layer 4 (in degrees);

[0056] L2=H2 / tgγ, H2 is the vertical distance between the coal seam 3 and the topsoil layer 4 (unit: m), and γ is the strike movement angle of the rock layer (unit: °).

[0057] It is understandable that when the coal seam 3 is horizontal, the horizontal distance between the upper reservoir 6 and the coal mining area 1 should be no less than L A , and / or, control the horizontal distance between the lower storage 5 and the coal mining area 1 to be no less than L A , which enables the upper reservoir 6 and / or the lower reservoir 5 to adapt to the horizontal coal seam 3 and be in a safe and stable position, while ensuring safe production in the mine.

[0058] It should be noted that the nearly horizontal coal seam 3 can also be considered to have a horizontal trend.

[0059] like Figure 4 As shown, in some embodiments, the method further includes:

[0060] When the coal seam 3 is inclined and the upper reservoir 6 is close to the top of the coal seam 3, the horizontal distance between the upper reservoir 6 and the mining area 1 is controlled to be no less than L B , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the top of the coal seam 3, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L B ;

[0061] Among them, L B =L1+L2+W, W is the width of the retaining belt at the edge of the mining area 1 (in meters);

[0062] L1 = H1 / tgφ, H1 is the thickness of the topsoil layer 4 (in m), φ is the movement angle of the topsoil layer 4 (in degrees);

[0063] L2=H2 / tgδ, H2 is the vertical distance between the coal seam 3 and the topsoil layer 4 (in m), and δ is the uphill movement angle of the rock layer (in degrees).

[0064] It is understandable that when the coal seam 3 is inclined and the upper reservoir 6 is close to the top of the coal seam 3, the horizontal distance between the upper reservoir 6 and the coal mining area 1 is controlled to be no less than L B , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the top of the coal seam 3, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L B , which enables the upper reservoir 6 and / or the lower reservoir 5 to adapt to the inclined coal seam 3 and be in a safe and stable position, while ensuring safe production in the mine.

[0065] like Figure 5 As shown, in some embodiments, the method further includes:

[0066] When the coal seam 3 is inclined and the upper reservoir 6 is close to the bottom of the coal seam 3, the horizontal distance between the upper reservoir 6 and the mining area 1 is controlled to be no less than L C , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the bottom of the coal seam 3, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than LC ;

[0067] Among them, L C =L1+L2+W, W is the width of the retaining belt at the edge of the mining area 1 (in meters);

[0068] L1 = H1 / tgφ, H1 is the thickness of the topsoil layer 4 (in m), φ is the movement angle of the topsoil layer 4 (in degrees);

[0069] L2=H2 / tgβ, H2 is the vertical distance between the coal seam 3 and the topsoil layer 4 (unit: m), and β is the downhill movement angle of the rock layer (unit: °).

[0070] It is understandable that when the coal seam 3 is inclined and the upper reservoir 6 is close to the bottom of the coal seam 3, the horizontal distance between the upper reservoir 6 and the coal mining area 1 is controlled to be no less than L C , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the bottom of the coal seam 3, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L C , which enables the upper reservoir 6 and / or the lower reservoir 5 to adapt to the inclined coal seam 3 and be in a safe and stable position, while ensuring safe production in the mine.

[0071] like Figure 5 As shown, in some embodiments, the method further includes:

[0072] When the coal seam 3 is inclined and the upper reservoir 6 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the topsoil layer 4 is less than the preset vertical distance, the horizontal distance between the upper reservoir 6 and the mining area 1 is controlled to be no less than L D , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the overburden layer 4 is less than the preset vertical distance, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L D ;

[0073] Among them, L D =L1+L2+L3+W;

[0074] L3=(H s -H2) / tgα,H s is the preset vertical spacing (in m), and α is the inclination angle of the coal seam 3 (in degrees);

[0075] M is the coal mining thickness (in m), and a, b, c and d are different preset coefficients.

[0076] It is understandable that when the coal seam 3 is inclined and the upper reservoir 6 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the topsoil layer 4 is less than the preset vertical distance, the horizontal distance between the upper reservoir 6 and the mining area 1 is controlled to be no less than LD , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the overburden layer 4 is less than the preset vertical distance, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L D , which enables the upper reservoir 6 and / or the lower reservoir 5 to adapt to the inclined coal seam 3 and be in a safe and stable position, while ensuring safe production in the mine.

[0077] It should be noted that different parameters of a, b and d can be selected according to the strength of the rock formation, and different coefficients of c can be selected according to the strength of the aquifer. For example, when the rock formation strength is medium hard, a = 0.23, b = 6.1, d - 10.42, and when the aquifer has medium water richness, c = 3.

[0078] Among them, when the coal seam 3 is inclined, and the upper reservoir 6 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the topsoil layer 4 is less than the preset vertical distance, the horizontal distance between the upper reservoir 6 and the coal mining area 1 is controlled to be no less than L D , and / or, when the coal seam 3 is inclined and the lower reservoir 5 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the overburden layer 4 is less than the preset vertical distance, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be no less than L D .

[0079] When the coal seam 3 is inclined, and the upper reservoir 6 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the topsoil layer 4 is not less than the preset vertical distance, the horizontal distance between the upper reservoir 6 and the mining area 1 is controlled to be not less than L C , and / or, when the coal seam 3 is inclined, and the lower reservoir 5 is close to the bottom of the coal seam 3, and the vertical distance between the coal seam 3 and the overburden layer 4 is not less than the preset vertical distance, the horizontal distance between the lower reservoir 5 and the coal mining area 1 is controlled to be not less than L C .

[0080] In some embodiments, β is: β=δ-Kα, δ is the uphill movement angle of the rock layer (in degrees), α is the inclination angle of the coal seam 3 (in degrees), and K is a preset coefficient.

[0081] It should be noted that K is the lithology correlation coefficient, which can be set according to actual needs and is not limited.

[0082] In some embodiments, the method further comprises:

[0083] An upper reservoir 6 and a lower reservoir 5 are constructed in a valley on the ground, and when constructing the upper reservoir 6 and the lower reservoir 5, anti-seepage treatment is performed on the bottom and surrounding areas of the upper reservoir 6 and the lower reservoir 5.

[0084] It can be understood that building the upper reservoir 6 and the lower reservoir 5 in the valley on the ground effectively utilizes the topography of the surface valley, improves the construction efficiency of the upper reservoir 6 and the lower reservoir 5, and reduces the construction cost of the upper reservoir 6 and the lower reservoir 5.

[0085] Anti-seepage treatment is performed on the bottom and periphery of the upper reservoir 6 and the lower reservoir 5, thereby reducing the loss of water resources and achieving effective protection and utilization of water resources.

[0086] It should be noted that the anti-seepage treatment of the upper reservoir 6 and the lower reservoir 5 can be achieved by setting an anti-seepage layer at the bottom and around it. For example, the anti-seepage layer includes reinforced concrete lining, composite drainage net, geotextile, geomembrane, bentonite pad and compacted foundation layer.

[0087] The method of this embodiment determines the water-rich intensity of the mining-induced separation zone 2, fully utilizes the groundwater resources and surface valleys after mining to determine the positions of the pumped-storage lower reservoir 5 and the upper reservoir 6, and builds a pumped-storage power station, which is of great significance to mine safety production and water resource protection and utilization.

[0088] It should be noted that, in the description of this disclosure, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of this disclosure, unless otherwise specified, the meaning of "plurality" is two or more.

[0089] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present disclosure includes additional implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present disclosure belong.

[0090] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0091] Although the embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are illustrative and are not to be construed as limitations on the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A method for storing energy by pumping out layer water from the surface of a coal mine, characterized in that: include: Determining the water-rich intensity of a mining separation zone in a coal mining area, wherein the mining separation zone is located in a rock layer between a coal seam and a topsoil layer in the coal mining area; When the water-rich intensity of the mining separation zone reaches a preset intensity, an upper reservoir and a lower reservoir are constructed on the ground at a preset distance from the mining area, wherein the height of the upper reservoir is greater than that of the lower reservoir; Pumping water from the mining separation zone to the lower reservoir, and when the power grid is in a valley period, pumping water from the lower reservoir to the upper reservoir to convert the power grid's electrical energy into water potential energy, and when the power grid is in a peak period, releasing water from the upper reservoir to the lower reservoir to convert the water potential energy into power grid's electrical energy; After the mining of the coal mining area is completed, the water in the upper reservoir and the lower reservoir is recharged into the mining separation zone.

2. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: Determine the unit water yield, permeability coefficient and single-hole pumping flow rate in the water-rich intensity of the mining-induced abscission zone; When the unit water yield of the mining detachment zone is not less than the preset unit water yield, the permeability coefficient of the mining detachment zone is not less than the first preset multiple of the pre-mining permeability coefficient, and the single-hole pumping flow rate of the mining detachment zone is not less than the preset single-hole pumping flow rate, it is determined that the water-rich intensity of the mining detachment zone has reached the preset intensity.

3. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: The capacity of the lower reservoir is constructed to be no less than the second preset multiple of the expected drainage volume of the mining separation zone; The capacity V1 of the lower reservoir is: V1=(A+B)hl / 2, where A is the bottom width of the lower reservoir, B is the top width of the lower reservoir, h is the depth of the lower reservoir, and l is the length of the lower reservoir. The estimated drainage volume Q of the mining separation zone is: The q i is the drainage volume per unit time of the ith borehole in the mining separation zone, and the t i is the effective utilization time of the i-th borehole in the mining separation zone.

4. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: The capacity of the upper warehouse is constructed to be no less than a third preset multiple of the capacity of the lower warehouse.

5. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: When the coal seam is horizontal, the horizontal distance between the upper reservoir and the mining area is controlled to be no less than L A , and / or, control the horizontal distance between the lower storage and the coal mining area to be no less than L A ; Among them, L A =L1+L2+W, where W is the width of the retaining belt at the edge of the coal mining area; L1=H1 / tgφ, where H1 is the thickness of the topsoil layer and φ is the movement angle of the topsoil layer; L2=H2 / tgγ, where H2 is the vertical distance between the coal seam and the topsoil layer, and γ is the strike movement angle of the rock layer.

6. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: When the coal seam is inclined and the upper reservoir is close to the top of the coal seam, the horizontal distance between the upper reservoir and the coal mining area is controlled to be no less than L B , and / or, when the coal seam is inclined and the lower reservoir is close to the top of the coal seam, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L B ; Among them, L B =L1+L2+W, where W is the width of the retaining belt at the edge of the coal mining area; L1=H1 / tgφ, where H1 is the thickness of the topsoil layer and φ is the movement angle of the topsoil layer; L2=H2 / tgδ, where H2 is the vertical distance between the coal seam and the topsoil layer, and δ is the uphill movement angle of the rock layer.

7. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: When the coal seam is inclined and the upper reservoir is close to the bottom of the coal seam, the horizontal distance between the upper reservoir and the coal mining area is controlled to be no less than L C , and / or, when the coal seam is inclined and the lower reservoir is close to the bottom of the coal seam, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L C ; Among them, L C =L1+L2+W, where W is the width of the retaining belt at the edge of the coal mining area; L1=H1 / tgφ, where H1 is the thickness of the topsoil layer and φ is the movement angle of the topsoil layer; L2=H2 / tgβ, where H2 is the vertical distance between the coal seam and the topsoil layer, and β is the downhill movement angle of the rock layer.

8. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 7, characterized in that: The method further comprises: When the coal seam is inclined, the upper reservoir is close to the bottom of the coal seam, and the vertical distance between the coal seam and the topsoil layer is less than the preset vertical distance, the horizontal distance between the upper reservoir and the mining area is controlled to be no less than L D , and / or, when the coal seam is inclined and the lower reservoir is close to the bottom of the coal seam, and the vertical distance between the coal seam and the topsoil layer is less than the preset vertical distance, the horizontal distance between the lower reservoir and the coal mining area is controlled to be no less than L D ; Among them, L D =L1+L2+L3+W; L3=(H s -H2) / tgα, the H s is a preset vertical spacing, and α is the inclination angle of the coal seam; The M is the coal mining thickness, and the a, b, c and d are different preset coefficients.

9. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 7, characterized in that: The β is: β=δ-Kα, where δ is the uphill movement angle of the rock layer, α is the inclination angle of the coal seam, and K is a preset coefficient.

10. The method for storing energy by pumping out stratum water from the coal mine surface according to claim 1, characterized in that: The method further comprises: The upper reservoir and the lower reservoir are constructed in the valley on the ground, and when constructing the upper reservoir and the lower reservoir, anti-seepage treatment is performed on the bottom and periphery of the upper reservoir and the lower reservoir.

Images