Methods and systems for filling solid waste slurry in underground coal mines

Abstract

This invention specifically discloses a method and system for filling solid waste slurry in underground coal mines. The method includes determining the target stratum where the borehole is located; drilling the borehole and positioning it within the target stratum; performing fracturing grouting and solid waste slurry filling grouting in the target area. The fracturing grouting forms a fracture network in the rock strata within the target area, and the solid waste slurry filling grouting fills the goaf through this fracture network. This method for filling solid waste slurry in underground coal mines can fill solid waste into underground goafs, fully utilizing underground space for waste disposal. It eliminates the need to bring the solid waste to the surface, reducing waste disposal costs and preventing damage to the surface environment. Furthermore, it can fill goafs, avoiding surface subsidence.

Description

Technical Field

[0001] This invention belongs to the field of coal mining technology, specifically relating to a method and system for filling solid waste slurry in underground coal mines. Background Technology

[0002] Coal mining is an important part of the energy industry; however, one of the problems that arises is the disposal of waste. Solid waste such as coal gangue and tailings has long been a focus of resource waste and environmental pollution.

[0003] The main treatment method in related technologies is to lift the waste into the well and landfill it. However, this method not only wastes potential resources and has high solid waste treatment costs, but also causes serious damage to the environment, leading to land degradation and deterioration of the geological environment. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a method for filling solid waste slurry in underground coal mines, which can fill solid waste into underground goaf areas, fully utilize underground space to treat waste, and reduce solid waste treatment costs.

[0005] Embodiments of the present invention also propose a coal mine underground solid waste slurry filling system.

[0006] The coal mine underground solid waste slurry filling method of this invention includes:

[0007] Determine the target stratigraphic position of the borehole;

[0008] Drilling is carried out, and the borehole is positioned within the target stratum.

[0009] The target area is subjected to fracturing grouting and solid waste slurry filling grouting. The fracturing grouting is used to form a fracture network in the rock strata within the target area, and the solid waste slurry filling grouting is used to fill the goaf through the fracture network.

[0010] The coal mine underground solid waste slurry filling method of the present invention can fill solid waste into the underground goaf, make full use of underground space to treat waste, eliminate the need to bring solid waste to the surface, reduce solid waste treatment costs, and avoid damage to the surface environment. It can also fill the goaf and prevent surface subsidence.

[0011] In some embodiments, determining the target formation level where the borehole is located includes:

[0012] Conduct advanced geological surveys and obtain survey data;

[0013] Based on the survey data, the stratigraphic positions of the rock fracture zone and collapse zone in the top plate of the working face were determined;

[0014] The boundary area between the rock fracture zone and the collapse zone on the top of the working face is taken as the target stratum, and high-level boreholes are arranged ahead of the working face.

[0015] In some embodiments, the drilling operation includes:

[0016] Arrange grouting drilling sites in roadways adjacent to the working face;

[0017] The target stratum is the area at the junction of the rock fracture zone and the caving zone on the top of the working face, and directional drilling is carried out.

[0018] Real-time measurement of geological and engineering parameters during drilling;

[0019] Based on the geological and engineering parameters, the drilling direction of the directional drilling is verified to ensure that the borehole is located in the target stratum.

[0020] In some embodiments, a measurement system is installed on the directional drill to perform real-time measurement of geological parameters, including at least one of resistivity, gamma, porosity, and rock density.

[0021] In some embodiments, the fracturing grouting and solid waste slurry filling grouting of the target area adopts segmented fracturing filling, which includes:

[0022] The goaf area after the working face has been mined out is divided into zones;

[0023] Based on the partitioning, the target formation where the borehole is located is segmented to form multiple grouting and filling sections;

[0024] Grouting pipes and packers are arranged in the borehole, and fracturing grouting and solid waste slurry filling grouting are carried out segment by segment in multiple grouting filling sections, starting from the bottom of the borehole.

[0025] In some embodiments, the fracturing grouting and solid waste slurry filling grouting include:

[0026] The grouting filling section is subjected to fracturing grouting to form a fracture network in the rock strata of the grouting filling section;

[0027] Simulation experiments were conducted on solid waste slurry to obtain simulation data;

[0028] Based on the simulation data and the permeability of the grouting section, the process parameters for the solid waste slurry filling grouting are determined.

[0029] The goaf was filled with solid waste slurry through grouting.

[0030] In some embodiments, the simulation data includes at least one of fluidity, permeability, and pressure distribution.

[0031] The coal mine underground solid waste slurry filling system of this invention is used for the construction of the coal mine underground solid waste slurry filling method described in any of the above embodiments, and includes:

[0032] A working chamber located in a roadway adjacent to the working face;

[0033] Drilling equipment, wherein the drilling equipment is disposed in the working chamber, and the drilling equipment is used to arrange high-level boreholes ahead of the working face;

[0034] Grouting equipment, which is located in the working chamber, is used for fracturing grouting and solid waste slurry filling grouting after the working face has been mined.

[0035] In some embodiments, the grouting equipment includes a grouting pipe and a packer located at the end of the grouting pipe.

[0036] In some embodiments, the grouting equipment includes multiple grouting pumps arranged in parallel. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure for filling coal mine underground solid waste slurry according to an embodiment of the present invention.

[0038] Figure 2 This is a process flow diagram of a coal mine underground solid waste slurry filling method according to another embodiment of the present invention.

[0039] Figure 3 This is a process flow diagram of a coal mine underground solid waste slurry filling method according to another embodiment of the present invention.

[0040] Figure 4 This is a process flow diagram of a coal mine underground solid waste slurry filling method according to another embodiment of the present invention.

[0041] Figure 5 This is a process flow diagram of a coal mine underground solid waste slurry filling method according to another embodiment of the present invention.

[0042] Figure 6 This is a process flow diagram of a coal mine underground solid waste slurry filling method according to another embodiment of the present invention.

[0043] Figure label:

[0044] 100. Drilling;

[0045] 200. Working face;

[0046] 300. Packer;

[0047] 400. Fragmented network;

[0048] 500. Grouting equipment. Detailed Implementation

[0049] Embodiments of the present invention are described in detail below, with examples of the embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0050] like Figure 1 and Figure 2 As shown, the coal mine underground solid waste slurry filling method of this embodiment includes:

[0051] S101. Determine the target stratum of borehole 100. Specifically, the location of borehole 100 needs to ensure its effectiveness. During the solid waste slurry filling grouting process, borehole 100 can serve as an effective grouting channel. At the same time, it is also necessary to make full use of the rock structure of the mining area to ensure that the solid waste slurry can penetrate and fill the goaf. Selecting a suitable target stratum can improve the feasibility of solid waste grouting, so as to ensure that the solid waste slurry can fully and uniformly penetrate and fill the goaf, thereby improving the strength and stability of the filling body after filling.

[0052] S102. Carry out the drilling of borehole 100 and place borehole 100 in the target stratum.

[0053] It should be noted that the construction of borehole 100 can be carried out in advance before the working face 200 is mined, and borehole 100 is located in the target stratum to ensure the accuracy of the borehole 100 path, the effectiveness of the grouting channel, and the feasibility of grouting. Borehole 100 can be drilled using directional drilling.

[0054] S103. Perform fracturing grouting and solid waste slurry filling grouting on the target area. Fracturing grouting is used to form a fracture network 400 in the rock strata within the target area. Solid waste slurry filling grouting is used to fill the goaf through the fracture network 400.

[0055] In other words, during grouting, a fracture network 400 is first created in the rock strata of the target area through fracturing grouting to improve the permeability of solid waste grouting and ensure the fluidity and filling effect of solid waste grout. After completing the fracturing grouting of the target area, solid waste grout filling grouting is then carried out to ensure that there is a sufficient amount of solid waste grout to fill the 200 goaf of the working face and ensure the filling effect.

[0056] The coal mine underground solid waste slurry filling method of the present invention can fill solid waste into the underground goaf, make full use of underground space to treat waste, eliminate the need to bring solid waste to the surface, reduce solid waste treatment costs, and avoid damage to the surface environment. It can also fill the goaf and prevent surface subsidence.

[0057] like Figure 3 As shown, in some embodiments, determining the target formation horizon where borehole 100 is located includes:

[0058] S201. Conduct advanced geological surveys and obtain survey data.

[0059] Specifically, in order to determine the target stratum, it is necessary to conduct advanced geological surveys and obtain survey data so as to judge the distribution of rock strata, the development of fractures, and the permeability and slurry flow of the rock strata on the 200-meter top plate of the working face.

[0060] Optionally, the target stratum is located in the top stratum of the working face at 200 meters.

[0061] S202. Based on the survey data, determine the stratigraphic position of the rock fracture zone and the collapse zone in the top plate of the working face 200.

[0062] Based on the rock strata control theory and the aforementioned survey data, the activity of the roof strata after the mining of working face 200 can be assessed, thereby determining the stratigraphic positions of the caving zone and fracture zone of working face 200. Furthermore, the target stratigraphic position can be determined based on the stratigraphic positions of the caving zone and fracture zone of working face 200, ensuring that the geological characteristics of the caving zone and fracture zone can be fully utilized during subsequent fracturing and grouting to form a large, highly permeable area and improve the grouting and filling effect of solid waste slurry.

[0063] S203. The boundary area between the rock fracture zone and the collapse zone on the top plate of working face 200 is taken as the target stratum, and a high-level borehole 100 is arranged ahead of working face 200.

[0064] Specifically, before the working face is mined, based on the survey and advance prediction of the rock fracture zone and the caving zone, the boundary area between the rock fracture zone and the caving zone of the roof of the working face 200 is set as the target stratum. Then, the trajectory of borehole 100 is arranged in the target stratum to guide the drilling direction of borehole 100 during the construction process.

[0065] like Figure 4 As shown, in some embodiments, the construction of borehole 100 includes:

[0066] S301. Arrange grouting drilling sites in the adjacent roadways of the working face 200.

[0067] In other words, borehole 100 is constructed before the mining of working face 200. Grouting drilling sites are set up in the roadways adjacent to working face 200 to facilitate the placement of borehole 100 ahead of working face 200. Drilling equipment is also placed in the roadways adjacent to working face 200 to facilitate equipment installation and control of the drilling trajectory, reduce the construction difficulty of borehole 100, and improve the efficiency and effect of filling grouting after the mining of working face 200 is completed.

[0068] S302. Targeting the stratum at the boundary between the rock fracture zone and the collapse zone on the 200-meter top plate of the working face, directional drilling is employed.

[0069] Specifically, directional drilling is carried out to drill a roughly horizontal borehole 100 in the target stratum, and the borehole 100 is located at the boundary between the rock fracture zone and the caving zone of the top plate of the working face 200.

[0070] S303. Real-time measurement of geological and engineering parameters while drilling.

[0071] During directional drilling, the geological parameters at the drill bit's location and the drilling engineering parameters are measured in real time to obtain data that reflects the corresponding geological properties.

[0072] S304. Based on geological and engineering parameters, the drilling direction of the directional drilling is verified to ensure that borehole 100 is located in the target stratum.

[0073] In other words, in order to ensure that borehole 100 is located at the boundary between the rock fracture zone and the collapse zone of the top plate of working face 200, the current geological properties are analyzed through geological parameters and engineering parameters to ensure that borehole 100 is located at the boundary between the rock fracture zone and the collapse zone.

[0074] When geological and engineering parameters undergo significant abrupt changes, it indicates that the drilling trajectory of borehole 100 has deviated, which is detrimental to subsequent grouting operations. It is necessary to correct the trajectory of borehole 100 in a timely manner.

[0075] In some embodiments, a measurement system is installed on the directional drill to perform real-time measurement of geological parameters, including at least one of resistivity, gamma, porosity, and rock density.

[0076] In this embodiment of the invention, a measurement system is set up near the drill bit of the directional drilling to obtain geological parameters during drilling. These geological parameters include one or more of resistivity, gamma, porosity, and rock density. For example, resistivity and gamma are used to determine geological properties, or resistivity, gamma, and porosity are used to make a comprehensive determination of geological properties.

[0077] Furthermore, measurement data can be obtained through other detection methods to accurately evaluate the geological properties and ensure that the drilling trajectory is located at the boundary between the rock fracture zone and the collapse zone.

[0078] like Figure 5 As shown, in some embodiments, the fracturing grouting and solid waste slurry filling grouting of the target area adopts segmented fracturing filling, which includes:

[0079] S401. Divide the goaf area after 200 mins in the working face into zones.

[0080] After a certain distance is mined from the working face 200, the goaf is filled through the high-level boreholes 100 arranged in the advanced working face 200. In order to improve the uniformity of the goaf filling and ensure the structural strength and stability of the filling body after filling, the goaf is divided into zones for filling. By reasonably dividing the size of the filling area at one time, it is ensured that the solid waste slurry can penetrate through the fracture mesh 400 and fill the goaf during the filling process.

[0081] S402. Based on zoning, the target stratum where borehole 100 is located is segmented to form multiple grouting and filling sections.

[0082] In other words, for different zones of the goaf, the corresponding target strata at the location of borehole 100 are segmented. When grouting is carried out through different grouting filling sections, the goaf in different zones can be effectively filled. The interval distance of the grouting filling sections is reasonably planned. For example, based on the development of the fracture network 400 when fracturing grouting at a grouting point, the reasonable distance between two adjacent grouting filling sections is determined to ensure that the grout can penetrate into the goaf during the solid waste grouting process and to ensure that the solid waste grout filling in each zone of the goaf is uniform and to ensure the stability of the filling structure.

[0083] S403. Grouting pipes and packers 300 are arranged in borehole 100. Starting from the bottom of borehole 100, fracturing grouting and solid waste slurry filling grouting are carried out segment by segment in multiple grouting filling sections.

[0084] During grouting, grouting pipes and packers 300 are arranged in borehole 100. The packers 300 enable the grout in the grouting pipes to flow in a concentrated manner to one of the grouting filling sections, ensuring that the grout can flow in a concentrated and directional manner. On the one hand, this can improve the effective diffusion of fracturing fluid in the grouting filling section during fracturing grouting and form a fracture network 400 in the grouting filling section. On the other hand, it can ensure that the solid waste grout is filled into the corresponding zone of the goaf with sufficient flow and pressure during the solid waste grouting process.

[0085] After the filling of the corresponding goaf area is completed through a grouting and filling section, the grouting pipe and packer 300 are moved to begin filling the next goaf area.

[0086] Furthermore, a backward segmented grouting method is adopted, starting from the bottom of borehole 100 and gradually moving towards the borehole opening of borehole 100, in order to maximize the use of the fracture network 400 generated by fracturing and prevent grout leakage.

[0087] like Figure 6 As shown, in some embodiments, fracturing grouting and solid waste slurry filling grouting include:

[0088] S501. Perform fracturing grouting on the grouting filling section to form a fracture network 400 in the rock strata of the grouting filling section.

[0089] Specifically, anti-swelling fracturing fluid is used for fracturing grouting to create a 400-fold fracture network in the top rock layer to enhance the permeability of the grouting fluid.

[0090] S502. Conduct simulation tests on solid waste slurry to obtain simulation data.

[0091] Based on fluid mechanics principles and formulas such as Darcy's Law, numerical simulations were performed on the flow, seepage, and pressure distribution of solid waste slurry. Darcy's Law describes the linear relationship between the seepage velocity of water in saturated soil and the hydraulic gradient.

[0092] S503. Based on simulation data and the permeability of the grouting filling section, determine the process parameters for solid waste slurry filling grouting.

[0093] In other words, by combining parameters such as rock permeability and grout properties, the grouting process parameters are optimized to ensure that the grout can fully penetrate the fissures and fill the goaf. The grouting process parameters include parameters such as flow rate and pressure, as well as the use of continuous grouting or multiple grouting intervals.

[0094] S504. Grouting is carried out to fill the goaf with solid waste slurry.

[0095] Specifically, after fracturing and grouting are completed, the grouting slurry is replaced with solid waste slurry. A high-efficiency, high-displacement, high-pressure pump system is adopted, and multiple grouting pumps are connected in parallel to ensure that the grouting slurry fills the 200 mined-out area of ​​the working face with sufficient flow and pressure to ensure the filling effect.

[0096] In some embodiments, the simulation data includes at least one of fluidity, permeability, and pressure distribution. That is, one type of simulation data or multiple types of simulation data can be used for comprehensive judgment to determine the process parameters for solid waste slurry filling grouting.

[0097] The coal mine underground solid waste slurry filling system of this invention is used for the construction of the coal mine underground solid waste slurry filling method of any of the above embodiments. It includes a working chamber, drilling equipment and grouting equipment 500. The working chamber is located in the roadway adjacent to the working face 200. The drilling equipment is installed in the working chamber and is used to arrange high-level boreholes 100 ahead of the working face 200. Optionally, the drilling equipment is a directional drill. The grouting equipment 500 is installed in the working chamber and is used to perform fracturing grouting and solid waste slurry filling grouting after the working face 200 is mined.

[0098] In some embodiments, the grouting device 500 includes a grouting pipe and a packer 300 disposed at the end of the grouting pipe. The grouting pipe can be a high-pressure rubber hose, and a perforated pipe is provided at the inner end of the grouting pipe. Grout is injected into the corresponding grouting and filling section through the through hole on the perforated pipe.

[0099] In some embodiments, the grouting equipment 500 includes multiple grouting pumps arranged in parallel to increase the flow rate and pressure of the grouting, ensuring that sufficient grouting fluid can be used to fill the goaf.

[0100] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0101] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0102] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0103] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0104] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions 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 one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments and features described in this specification.

[0105] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A method for filling solid waste slurry in underground coal mines, characterized in that, include: Determine the target stratigraphic position of the borehole; Drilling is carried out, and the borehole is positioned within the target stratum. The target area is subjected to fracturing grouting and solid waste slurry filling grouting. The fracturing grouting is used to form a fracture network in the rock strata within the target area, and the solid waste slurry filling grouting is used to fill the goaf through the fracture network. Determining the target stratigraphic position of the borehole includes: Conduct advanced geological surveys and obtain survey data; Based on the survey data, the stratigraphic positions of the rock fracture zone and the collapse zone in the top plate of the working face were determined; The boundary area between the rock fracture zone and the collapse zone on the top plate of the working face is taken as the target stratum, and high-level boreholes are arranged ahead of the working face. The drilling operation includes: Arrange grouting drilling sites in roadways adjacent to the working face; The target stratum is the area at the junction of the rock fracture zone and the caving zone on the top of the working face, and directional drilling is carried out. Real-time measurement of geological and engineering parameters during drilling; Based on the geological and engineering parameters, the drilling direction of the directional drilling is verified to ensure that the borehole is located in the target stratum. The fracturing grouting and solid waste slurry filling grouting of the target area adopts a segmented fracturing filling method, which includes: The goaf area after the working face has been mined out is divided into zones; Based on the partitioning, the target formation where the borehole is located is segmented to form multiple grouting and filling sections; Grouting pipes and packers are arranged in the borehole, and fracturing grouting and solid waste slurry filling grouting are carried out segment by segment in multiple grouting filling sections, starting from the bottom of the borehole. The fracturing grouting and solid waste slurry filling grouting include: The grouting and filling section is subjected to fracturing grouting to form a fracture network in the rock strata of the grouting and filling section; Simulation experiments were conducted on solid waste slurry to obtain simulation data; Based on the simulation data and the permeability of the grouting section, the process parameters for the solid waste slurry filling grouting are determined. The goaf was filled with solid waste slurry through grouting.

2. The method for filling solid waste slurry in underground coal mines according to claim 1, characterized in that, A measurement system is installed on the directional drill to perform real-time measurement of geological parameters, including at least one of resistivity, porosity, and rock density.

3. The method for filling solid waste slurry in underground coal mines according to claim 1, characterized in that, The simulation data includes at least one of fluidity, permeability, and pressure distribution.

4. A coal mine underground solid waste slurry filling system, used for the construction of the coal mine underground solid waste slurry filling method according to any one of claims 1-3, characterized in that, include: A working chamber located in a roadway adjacent to the working face; Drilling equipment, wherein the drilling equipment is disposed in the working chamber, and the drilling equipment is used to arrange high-level boreholes ahead of the working face; Grouting equipment, which is located in the working chamber, is used for fracturing grouting and solid waste slurry filling grouting after the working face has been mined.

5. The coal mine underground solid waste slurry filling system according to claim 4, characterized in that, The grouting equipment includes a grouting pipe and a packer located at the end of the grouting pipe.

6. The coal mine underground solid waste slurry filling system according to claim 4, characterized in that, The grouting equipment includes multiple grouting pumps arranged in parallel.

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