Accurate layer following exploration treatment method based on large-mining-depth aquifer area treatment
By conducting advanced exploration and grouting treatment on the ground, the problems of high difficulty in drilling underground in deep coal mines and high difficulty in sealing high-pressure Ordovician limestone water were solved, achieving safe and efficient underground construction and water hazard prevention, and ensuring the safety of workers.
Patent Information
- Application Number
- CN202511982774.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-02-03
AI Technical Summary
In deep coal mines, drilling is difficult and time-consuming, and there are challenges in controlling the blockage of high-pressure Ordovician limestone water, which is also difficult, time-consuming, and risky. In addition, the safety of underground workers is difficult to guarantee.
The method of precise stratum exploration based on the treatment of aquifers at great depths is adopted. The method involves advance exploration and grouting treatment through ground drilling. The steps include delineating the treatment area, selecting the target layer for drilling, designing vertical supplementary exploration holes, core drilling, core identification, cross-verification, and high-pressure grouting and sealing. This method enables one hole to be used for multiple purposes and ensures the accuracy of the drilling trajectory.
It has achieved safe and efficient underground construction, reduced the risk of water inrush accidents, reduced the probability of underground workers being exposed to high-risk environments, improved resource utilization, reduced mine water inflow and the probability of water-related accidents, and ensured the safety of workers.
Smart Images
Figure CN121451964A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of drilling technology, and in particular to a method for precise layer-following exploration and management of aquifer areas at great mining depths. Background Technology
[0002] With the development of my country's coal industry, the deepening of coal mine water control efforts, and the depletion of shallow coal resources, most domestic coal mines face complex and diverse mining problems. Notably, significant changes have occurred compared to the past in various aspects, including mining depth and strata in eastern coal mines, mining scale and intensity in central and western coal mines, mining methods and technologies, mining environment, hydrogeological conditions related to water inflow, and underground water control technologies. As shallow and upper-seam easily mined coal reserves gradually dwindle, most mines are beginning to shift to deep coal seam mining, leading to increasingly complex and diverse mining problems, the most prominent being deep mining and high pressure.
[0003] The coal seam floor contains a highly pressurized karst aquifer with strong or extremely strong water content. The risks of using underground exploration, grouting to reinforce the floor, or modifying the aquifer are extremely high. (1) The following requirements should be met during construction: After the grouting to reinforce the floor or the modification of the aquifer is completed, an evaluation of the effect should be organized; the water inrush coefficient of the coal mining face should not exceed 0.1 MPa / m. (2) Underground exploration, grouting to reinforce the floor, etc. are extremely risky. In addition, the personnel quota limit makes it more difficult to implement such projects and the on-site operation organization is more complicated. Safety technical measures must be strictly implemented, process control should be strengthened, and the personnel positioning and monitoring system should be reliably operated. (3) The construction plan should be optimized, advanced and efficient equipment should be used, the level of automated operation should be improved, and the number of people working underground should be reduced. (4) All exploration and grouting operations must be based on a full analysis of geological conditions and precise hole layout should be carried out. Pressure and flow changes should be monitored in real time to prevent water inrush accidents.
[0004] Based on this, the current problems are: First, underground drilling needs to cross multiple coal seams at an angle, which is prone to hole collapse, making construction difficult and time-consuming; Second, underground drilling must be stopped, which creates a significant conflict with the tunnel excavation project; Third, maintaining the quota for underground drilling personnel for a long time has squeezed the quota for mine production personnel; Fourth, encountering high-pressure Ordovician limestone water underground is difficult to seal and treat, has a long cycle, and poses great construction risks.
[0005] How to provide safe, efficient and advanced exploration and treatment solutions to address the safety risks of deep coal seam mining faced by coal mining enterprises and alleviate the pressure of underground construction has become an urgent problem to be solved. Summary of the Invention
[0006] To address the aforementioned problems, this invention provides a precise layer-based exploration and treatment method for the treatment of aquifers at deep mining depths. This method explores the water-bearing capacity, structural development characteristics, water conductivity, and vertical fracture channels of the aquifer at the coal seam floor. It also reinforces the water-conducting channels at the coal seam floor by grouting to prevent the threat of Ordovician limestone water to the coal seam floor and reduce mine water inflow, thus protecting the safety of on-site workers.
[0007] To achieve the above objectives, this invention provides a precise layer-tracking exploration and management method for aquifer area management at great mining depths, comprising: Delineate the scope of regional governance and conduct a feasibility study, select the target layer for drilling and governance, and design vertical supplementary exploration boreholes based on analytical data and geological information; Drilling is carried out over the area to be treated, and the spacing between the planar holes is arranged according to the size of the area to be treated, and the drill holes are made to intersect the fault structure perpendicularly. The vertical supplementary exploration holes are used for core drilling. Cores are taken from the target layer within a preset range above and below the target layer to identify physical and chemical characteristics. Core logging and identification are performed to record the lithological characteristics of the top and bottom plates of the target layer. During the drilling of the target layer, drilling data is collected, and the lithological characteristics of the top and bottom plates of the target layer are used to guide the horizontal boreholes to assist in layer identification. When the amount of drilling fluid loss or leakage reaches a preset threshold, grouting should be performed immediately to seal the leak. During the construction process, cross-construction verification and geophysical exploration verification were carried out.
[0008] As a further improvement of the present invention, the step of delineating the area for remediation and conducting a feasibility study, and selecting the target layer for drilling remediation, includes: Calculate the water inrush coefficient and the thickness of the safe water-retaining layer within the treatment area, and select the target layer for drilling treatment through calculation and verification; The calculation of the water inrush coefficient is required to be no greater than 0.1 MPa / m, and the selection of the stratigraphic level is optimized by drawing contour maps.
[0009] As a further improvement of the present invention, the spacing between the planar holes is dynamically adjusted based on the size of the treatment area to ensure that the borehole layout covers areas with high incidence of fault structures, thereby improving the exploration accuracy.
[0010] As a further improvement of the present invention, one or two vertical exploration holes are constructed, located at the beginning and end of the treatment area.
[0011] As a further improvement of the present invention, the core logging and identification includes recording lithological color, hardness and fracture development characteristics, and providing benchmark data for horizontal borehole layer identification.
[0012] As a further improvement of the present invention, during the drilling of the target layer, drilling data is collected, and the horizontal borehole-assisted layer determination is guided by the lithological characteristics of the top and bottom plates of the target layer, including: Environmental compensation parameters and gamma values of the directional monitoring equipment were set in the target layer. The time for rock cuttings to return from the borehole was measured using the physical calibration method. The drilling speed was measured during the drilling process in the target layer. The physical morphology, water-wet state, and fracture joints of the returned rock cuttings were analyzed under a microscope and compared with the lithological characteristics of the rock cuttings from the vertical exploration borehole. At the same time, chemical property tests were performed.
[0013] As a further improvement of the present invention, chemical property testing is performed, including: The residue content was calculated by reacting with 75% dilute hydrochloric acid. The threshold for the percentage of residue content is set to ≤10%. If the residue content is >10%, the drilling trajectory is adjusted to ensure the accuracy of layer following.
[0014] As a further improvement to the present invention, during the construction process, cross-construction verification and geophysical verification are carried out, including: The exploration holes and treatment holes were constructed alternately using a staggered drilling method, and the uniformity and integrity of the grouting area were verified by geophysical exploration.
[0015] As a further improvement of the present invention, the grouting and sealing adopts a high-pressure grouting process, and the grouting pressure is dynamically controlled according to the crack development characteristics to prevent the induction of water inrush accidents.
[0016] As a further improvement of the present invention, horizontal holes with straight boreholes, directional drilling, and directional branching are used to explore and reinforce the aquifer at the bottom of the coal seam; wherein, vertical exploration, horizontal branching treatment, and cross-verification are completed through a single borehole, and the horizontal branching treatment includes grouting. Compared with the prior art, the beneficial effects of the present invention are as follows: This invention adopts a standardized process of "determining, setting, exploring, judging, injecting, verifying, and concluding" to achieve the orderly advancement of exploration and treatment work, and solves the exploration contradiction caused by the need to stop drilling operations in traditional downhole drilling. At the same time, by comparing and analyzing the characteristics of rock cuttings from vertical holes and horizontal holes, accurate layer judgment is achieved, ensuring that the drilling trajectory is accurately controlled at the target layer. Through the technical solution of straight holes plus directional branch holes, the invention achieves multi-functional integration of exploration, grouting, and verification, which significantly reduces the amount of repetitive work and improves resource utilization.
[0017] This invention utilizes surface drilling for advanced exploration and grouting treatment, avoiding the high-pressure Ordovician limestone water inrush accident that may be induced by direct underground construction, thus reducing the risk of such accidents. By replacing underground construction with surface operations, the probability of workers being exposed to high-risk environments is significantly reduced, which complies with the mine safety supervision bureau's control requirements on the number of personnel going underground, achieving the safety goal of "reducing personnel and increasing efficiency" and reducing threats to personnel safety.
[0018] This invention transforms the aquifer into a relatively impermeable layer through grouting modification, effectively blocking the threat of Ordovician limestone water to the mine, reducing the mine's water inflow, and achieving water resource protection; it can reduce the probability of coal mine water hazard accidents, ensure the safety of workers, and at the same time reduce the disturbance of water control projects to the mining area environment.
[0019] The technical process of this invention is clear and easy for on-site personnel to master and implement. It can be widely applied to deep coal mines in the east and high-pressure mines in the central and western regions, providing a standardized solution for solving the problem of aquifer management at great mining depths. Attached Figure Description
[0020] Figure 1 This is a control flowchart of a precise layer-following exploration and treatment method for aquifer area management based on deep mining depth, as disclosed in one embodiment of the present invention. Figure 2 This is a vertical cross-sectional schematic diagram of a single hole used for multiple purposes, as disclosed in an embodiment of the present invention; Figure 3 This is a schematic diagram of a single hole used for multiple purposes, as disclosed in an embodiment of the present invention. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] The present invention will now be described in further detail with reference to the accompanying drawings: like Figure 1As shown, the present invention provides a precise layer-following exploration and treatment method for deep-mining aquifer areas, offering a safe and efficient advanced exploration and treatment solution for deep-mining, high-pressure mines, addressing the safety risks faced by coal mining enterprises in deep coal seam mining. The core of this method lies in: exploring the water-bearing capacity, structural development characteristics, water conductivity, and vertical fracture channels of the aquifer at the coal seam floor; and grouting and reinforcing the water-conducting channels (water-conducting faults, water-conducting collapse columns, and water-conducting fractures, etc.) at the coal seam floor. The highlight and key feature of this technical solution is that it is a complete set of precise layer-following exploration and treatment technologies for coal seam floor water hazards, combining "determination, design, exploration, judgment, grouting, verification, and conclusion," enabling multiple uses for a single borehole. Specifically, it includes: S1. Define: Delineate the scope of regional treatment and conduct a feasibility study, select the target layer for drilling treatment, and design vertical supplementary exploration boreholes based on analysis data and geological data. This includes: Calculate the water inrush coefficient and the thickness of the safe water-retaining layer within the treatment area, and select the target layer for drilling treatment through calculation and verification; The calculation of the water inrush coefficient should not exceed 0.1 MPa / m, and the selection of the stratigraphic level should be optimized by drawing contour maps.
[0023] Furthermore, One to two vertical exploration holes will be constructed, located at the beginning and end of the area to be treated.
[0024] S2. Suppose: Drilling is carried out within the area to be treated, and the spacing between planar holes is arranged according to the size of the area to be treated, and the drill holes are perpendicular to the fault structure. in, The spacing between planar boreholes is dynamically adjusted based on the size of the treatment area to ensure that the borehole layout covers areas with high incidence of fault structures, thereby improving exploration accuracy.
[0025] S3, Explore: such as Figure 2 As shown, vertical supplementary exploration holes are drilled for coring. Cores are taken from the target layer within a preset range above and below to identify physical and chemical characteristics. Core logging and identification are performed to record the lithological characteristics of the top and bottom plates of the target layer (including false tops and false bottoms) so as to facilitate cross-verification and identification with the horizontal holes constructed later. in, The preset range is 30m, that is: core samples are taken from 30m above and below the target layer to identify physical and chemical characteristics; Core logging and identification includes recording lithology, color, hardness, and fracture development characteristics, and providing benchmark data for horizontal borehole layer identification.
[0026] S4. Judgment: During the drilling of the target layer, drilling data is collected, and the lithological characteristics of the top and bottom plates of the target layer guide the horizontal borehole drilling (e.g., Figure 2 , 3 (As shown) Auxiliary layer determination; in, Environmental compensation parameters for directional monitoring equipment were set in the target layer, and gamma values (target layer lithological gamma radiation values) were calibrated. The uptake time of cuttings in the borehole was determined using the physical calibration method. The drilling speed (composite drilling, directional drilling time) was measured during the drilling process in the target layer. The physical morphology, water-wet state (fully dry, semi-dry), and fracture joint analysis of the uptake cuttings were performed under a microscope. The lithological characteristics of the cuttings were compared with those of the cuttings from the vertical exploration borehole. At the same time, chemical property tests were conducted.
[0027] Furthermore, Chemical property tests were conducted, including: The target layer rock fragments were reacted with 75% dilute hydrochloric acid (dried until completely dry), and then a certain mass was weighed using an electronic scale and placed in a beaker or other reaction vessel for reaction testing. After the residue was completely dry, it was weighed again, and the content percentage was calibrated and calculated. The threshold for the percentage of residue content is set to ≤10%. If the residue content is >10%, the drilling trajectory is adjusted to ensure the accuracy of layer following.
[0028] S5. Note: When the amount of drilling fluid loss or leakage reaches the preset threshold, grouting should be performed immediately to seal the leak. in, The preset threshold is 5m 3 / h, if drilling fluid loss or leakage exceeds 5m 3 / h means grouting and sealing are performed; The grouting and sealing process uses high-pressure grouting technology, and the grouting pressure is dynamically controlled according to the characteristics of crack development to prevent water inrush accidents.
[0029] S6. Verification: During the construction process, cross-construction verification and geophysical verification are carried out.
[0030] in, The exploration holes and treatment holes were constructed alternately using a staggered drilling method, and the uniformity and integrity of the grouting area were verified by geophysical exploration.
[0031] S7. Conclusion: After verification, prepare a project completion report, summarize the results, and provide guidance for subsequent work.
[0032] This invention employs straight holes, directional drilling, and directional branching horizontal holes to explore and reinforce the aquifer at the bottom of the coal seam; wherein, vertical exploration, horizontal branch treatment, and cross-verification are completed through a single borehole, and horizontal branch treatment includes grouting.
[0033] After evaluation and application, the method of this invention is sufficient to meet mining conditions, effectively alleviating underground construction pressure and reducing risks. By using vertical boreholes and directional branch holes, and employing directional drilling and layer-tracing techniques, the water-bearing capacity, structural development characteristics, water conductivity, and vertical fracture channels of the aquifer at the coal seam floor are investigated. Grouting is then used to reinforce the water-conducting channels (water-conducting faults, water-conducting collapse columns, and water-conducting fractures, etc.) at the coal seam floor. This grouting transforms the aquifer between the coal seam and the Ordovician limestone layer into a relatively impermeable layer, preventing the vertical recharge of Ordovician limestone water to the upper aquifer during mining activities or the direct threat of water inrush to the working face from Ordovician limestone water. This achieves a preventative effect on multiple aquifers at the coal seam floor. Example
[0034] The method of this invention is used to explore the water-bearing capacity, structural development characteristics, water conductivity, and vertical fracture channels of the aquifer at the bottom of the coal seam, and to reinforce the water-conducting channels (water-conducting faults, water-conducting collapse columns, and water-conducting fractures, etc.) at the bottom of the coal seam by grouting, specifically including: Step 1: Delineate the treatment area and demonstrate the scope of exploration and grouting reinforcement. The purpose is to calculate the safety water inrush coefficient of the treatment area and select the optimal drilling exploration treatment layer.
[0035] Step 2: Design the drilling layout for the area to be treated after research and demonstration. The spacing between the planar boreholes should be reasonably arranged according to the size of the treatment area (the specification requires that it should not exceed 60 meters). The planar boreholes should intersect the fault structure as perpendicularly as possible to maximize the use of drilling to expose the structure and ensure the effect of fine exploration.
[0036] Step 3: Exploration: Construct 1-2 vertical exploration holes (coring), preferably at the beginning and end of the treatment area, to facilitate comparative analysis and to understand local differences.
[0037] Step 4: Judgment: Collect and organize actual drilling data, determine the characteristics of rock cuttings through comparative analysis, and guide the determination of layers in horizontal boreholes.
[0038] Step 5: Note: High-pressure grouting is used to seal cracks on the ground. For structural areas, the grouting frequency can be increased or the grouting reinforcement method can be adjusted.
[0039] Step 6: Verification: After the completion of the cross-construction verification and regional governance project, geophysical verification will be carried out using both well and surface methods.
[0040] Step 7: Conclusion: After verification, compile the project completion report, summarize and refine the results, and provide guidance for subsequent work (evaluation of exploration-to-mining, mining-to-excavation integration, etc.).
[0041] This invention provides a complete set of precise coal seam floor water hazard detection and treatment technologies that combine "determination, setting, exploration, judgment, injection, verification, and conclusion," enabling multiple uses for a single borehole.
[0042] Advantages of this invention: This invention adopts a standardized process of "determining, setting, exploring, judging, injecting, verifying, and concluding" to achieve the orderly advancement of exploration and treatment work, and solves the exploration contradiction caused by the need to stop drilling operations in traditional downhole drilling. At the same time, by comparing and analyzing the characteristics of rock cuttings from vertical holes and horizontal holes, accurate layer judgment is achieved, ensuring that the drilling trajectory is accurately controlled at the target layer. Through the technical solution of straight holes plus directional branch holes, the invention achieves multi-functional integration of exploration, grouting, and verification, which significantly reduces the amount of repetitive work and improves resource utilization.
[0043] This invention utilizes surface drilling for advanced exploration and grouting treatment, avoiding the high-pressure Ordovician limestone water inrush accident that may be induced by direct underground construction, thus reducing the risk of such accidents. By replacing underground construction with surface operations, the probability of workers being exposed to high-risk environments is significantly reduced, which complies with the mine safety supervision bureau's control requirements on the number of personnel going underground, achieving the safety goal of "reducing personnel and increasing efficiency" and reducing threats to personnel safety.
[0044] This invention transforms the aquifer into a relatively impermeable layer through grouting modification, effectively blocking the threat of Ordovician limestone water to the mine, reducing the mine's water inflow, and achieving water resource protection; it can reduce the probability of coal mine water hazard accidents, ensure the safety of workers, and at the same time reduce the disturbance of water control projects to the mining area environment.
[0045] The technical process of this invention is clear, mature and reliable, and easy for on-site personnel to master and implement. It can be widely applied to deep coal mines in the east and high-pressure mines in the central and western regions. It can prevent the threat of Ordovician limestone water in the coal seam floor, reduce mine water inrush and protect the safety of on-site workers, realize green mining, reduce safety risks, and generate significant social benefits. It provides a standardized solution for solving the problem of aquifer management in deep mining areas.
[0046] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A precise layer-tracking exploration and treatment method for aquifer area management at great extraction depths, characterized in that: include: Delineate the scope of regional governance and conduct a feasibility study, select the target layer for drilling and governance, and design vertical supplementary exploration boreholes based on analytical data and geological information; Drilling is carried out over the area to be treated, and the spacing between the planar holes is arranged according to the size of the area to be treated, and the drill holes are made to intersect the fault structure perpendicularly. The vertical supplementary exploration holes are used for core drilling. Cores are taken from the target layer within a preset range above and below the target layer to identify physical and chemical characteristics. Core logging and identification are performed to record the lithological characteristics of the top and bottom plates of the target layer. During the drilling of the target layer, drilling data is collected, and the lithological characteristics of the top and bottom plates of the target layer are used to guide the horizontal boreholes to assist in layer identification. When the amount of drilling fluid loss or leakage reaches a preset threshold, grouting should be performed immediately to seal the leak. During the construction process, cross-construction verification and geophysical exploration verification were carried out.
2. The precise layer-following exploration and treatment method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: The process of delineating the area for remediation and conducting a feasibility study, and selecting the target layer for drilling remediation, includes: Calculate the water inrush coefficient and the thickness of the safe water-retaining layer within the treatment area, and select the target layer for drilling treatment through calculation and verification; The calculation of the water inrush coefficient is required to be no greater than 0.1 MPa / m, and the selection of the stratigraphic level is optimized by drawing contour maps.
3. The precise layer-following exploration and treatment method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: The spacing between the planar boreholes is dynamically adjusted based on the size of the treatment area to ensure that the borehole layout covers areas with high incidence of fault structures, thereby improving the accuracy of the exploration.
4. The precise layer-tracking exploration and management method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: One or two vertical exploration holes are constructed, located at the beginning and end of the treatment area.
5. The precise layer-tracking exploration and treatment method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: The core logging and identification process includes recording lithology, color, hardness, and fracture development characteristics, and providing benchmark data for horizontal borehole layer identification.
6. The precise layer-tracking exploration and management method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: During drilling of the target layer, drilling data is collected and used in conjunction with the lithological characteristics of the top and bottom plates of the target layer to guide horizontal borehole-assisted layer identification, including: Environmental compensation parameters and gamma values of the directional monitoring equipment were set in the target layer. The time for rock cuttings to return from the borehole was measured using the physical calibration method. The drilling speed was measured during the drilling process in the target layer. The physical morphology, water-wet state, and fracture joints of the returned rock cuttings were analyzed under a microscope and compared with the lithological characteristics of the rock cuttings from the vertical exploration borehole. At the same time, chemical property tests were performed.
7. The precise layer-following exploration and management method for aquifer area management based on deep mining depth as described in claim 6, characterized in that: Chemical property tests were conducted, including: The residue content was calculated by reacting with 75% dilute hydrochloric acid. The threshold for the percentage of residue content is set to ≤10%. If the residue content is >10%, the drilling trajectory is adjusted to ensure the accuracy of layer following.
8. The precise layer-tracking exploration and management method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: During construction, cross-construction verification and geophysical verification were carried out, including: The exploration holes and treatment holes were constructed alternately using a staggered drilling method, and the uniformity and integrity of the grouting area were verified by geophysical exploration.
9. The precise layer-tracking exploration and management method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: The grouting and sealing process employs high-pressure grouting, with the grouting pressure dynamically controlled based on the fracture development characteristics to prevent water inrush accidents.
10. The precise layer-tracking exploration and management method for aquifer area management based on deep mining depth as described in claim 1, characterized in that: The aquifer at the bottom of the coal seam is explored and reinforced by grouting using straight holes, directional drilling, and directional branching horizontal holes. Vertical exploration, horizontal branching treatment, and cross-verification are completed through a single borehole, and the horizontal branching treatment includes grouting.