Remining method for residual coal resources in old goaf
By evaluating and planning the re-harvestment of old goaf resources, combining geological radar and grouting and sealing technology, the problem of low resource recovery rate in old goaf areas is solved, and safe and efficient coal resource recovery is achieved.
Patent Information
- Application Number
- CN202510722366.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-07-01
AI Technical Summary
The recovery rate of residual coal resources in the old goaf is low, and the traditional re-finishing methods have poor adaptability and low safety, so the resource recovery rate needs to be improved.
Through the assessment of mine overview and construction conditions, resource reserves and production capacity are determined, re-production area planning and deployment, real-time detection and stress monitoring are adopted for geological radar, combined with grouting and packaging and efficient equipment, safe pretreatment and environmental protection management are implemented, and power supply and distribution, ventilation and dust removal systems are optimized.
The recovery rate of residual coal resources in the old goaf has been improved, ensuring the safety and economicality of mining, reducing energy consumption and reducing environmental pollution.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of coal mining, and in particular to a method for re-mining residual coal resources in an old goaf. Background Art
[0002] There are a lot of residual coal resources in the old goaf, especially in the areas mined before 2001. Because the coal mining methods were backward at that time, the resource recovery rate was low, and the working face recovery rate was only about 25-30%, resulting in a waste of coal resources. Traditional re-mining methods have many problems, such as poor adaptability to the geological conditions of the goaf, low mining safety, and the resource recovery rate still needs to be improved. Therefore, an efficient, safe and economical method for re-mining residual coal resources in old goaf is urgently needed. Summary of the invention
[0003] In view of this, the purpose of the present invention is to provide a method for re-mining residual coal resources in old goafs to solve the problems pointed out in the background technology, improve the recovery rate of residual coal resources in old goafs, and ensure the safety and economy of the mining process.
[0004] In order to achieve the above-mentioned invention object, the technical solution adopted is as follows: A method for re-mining residual coal resources in old goaf areas, comprising the following steps: (1) Mine overview and construction conditions assessment: Collect and analyze the basic information of the mine, such as its transportation location, topography, meteorology, surface and surrounding areas; conduct a comprehensive review of the mine's external construction conditions, such as transportation conditions, power supply and communication conditions, water source conditions, and supply conditions of major building materials; conduct a comprehensive review of the mine's stratigraphic characteristics, geological structure, coal seam occurrence, hydrogeological overview and other resource conditions to determine whether the internal conditions of the project construction meet the construction requirements; (2) Determination of resource reserves and production capacity: Based on the scale of the mine, geological conditions and the mining scope of the old goaf, determine the resource reserves and designed production capacity of the re-mining area of the mine, and calculate the mining service life of the re-mining area of the mine; (3) Planning and deployment of the re-mining area: Analyze the mine development mode, horizontal layout and mining area division, tunnel layout and cross-section, coal mining method, main production system and other mine production and construction conditions; conduct in-depth investigations to understand the coal resource endowment, roof and water and gas accumulation in the goaf area; determine the mine re-mining area tunnel layout and mining connection and other development deployment conditions; determine the re-mining area tunnel layout, coal mining method and process and other underground re-mining area mining methods; determine the underground coal transportation and underground auxiliary transportation methods through technical comparison and selection, and select the matching models of newly added related equipment; analyze the mine gas emission and mine gas level, calculate the mine air volume, and distribute the air volume, calculate the mine negative pressure and check or select new ventilation equipment; (4)Division of the re-mining area: By analyzing the damage situation of the coal pillars in the old goaf, the coal pillars are used as the partition boundaries; if there are no coal pillars, grouting is used to form artificial boundaries. (5)Selection of mining technology: According to the mine conditions, the complete set of comprehensive mining technology for residual coal in old mines or the conventional wall mining technology is selected for residual coal recovery. (6)Safety pretreatment: Support and maintain the old goaf where the roof has not caved in, and discharge gas and drain water in advance. (7)Dynamic mining control: Use ground-penetrating radar to detect the broken coal zone in real time, dynamically adjust the working face advancement parameters in combination with stress monitoring data, and monitor the gas concentration, water level of accumulated water, and ventilation negative pressure in the re-mining area in real time, and link to control the gas discharge equipment and drainage equipment. (8)System optimization design: Optimize the energy consumption of the underground power supply system, ventilation system, and dust removal system, and select high-efficiency equipment to reduce energy consumption. (9)Environmental protection treatment: Implement dust suppression, sewage and wastewater treatment, noise control, and surface subsidence monitoring and repair measures.
[0005] As a further improvement of the present invention, in step (4), grouting is used to form an artificial boundary, which specifically includes the following steps: According to the geological structure of the goaf, a high-pressure grouting device is used to inject slurry materials into the target area to form a continuous isolation belt, and the thickness of the isolation belt is 3-5 meters, and the compressive strength is ≥15 MPa.
[0006] As a further improvement of the present invention, the slurry material includes a cement-based composite material and a chemical reinforcing agent.
[0007] As a further improvement of the present invention, in step (9), the dust suppression measures include: installing a spray dust suppression device at the excavation and working face, and using a polymer dust suppressant to cover the coal dust diffusion area.
[0008] The beneficial effects of the present invention are as follows: Through multi-faceted analysis such as the mine overview and construction condition assessment, the present invention accurately determines the mining range and resource reserves, and then combines steps such as the re-mining area planning and deployment to effectively solve the problem of poor adaptability of traditional re-mining methods to the geological conditions of the goaf, realize the efficient recovery of residual coal resources, and significantly improve the resource recovery rate. Specific embodiments
[0009] The following embodiments are intended to further illustrate the present invention, but should not be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention still fall within the protection scope of the present invention.
[0010] A method for re-mining residual coal resources in old goafs includes the following steps: (1)General situation of the mine and assessment of construction conditions: Collect and analyze the basic conditions of the mine, such as its transportation location, topography, meteorology, surface and adjacent relations; comprehensively review the external construction conditions such as the mine's transportation conditions, power supply and communication conditions, water source conditions, and supply conditions of major building materials; comprehensively review the formation characteristics, geological structure, coal seam occurrence, hydrogeological situation, and other resource conditions of the mine to determine that the internal conditions for project construction meet the construction requirements. (2)Determination of resource reserves and production capacity: Determine the recoverable resource reserves and designed production capacity of the mine's secondary mining area based on the mine scale, geological conditions, and the mining scope of the old goaf, and calculate the service life of the mine's secondary mining area. (3)Planning and deployment of the secondary mining area: Analyze the mine's production and construction conditions, such as the mine's development method, horizontal layout, mining area division, roadway layout and section, coal mining method, and main production systems; deeply investigate and understand the occurrence of coal resources, roof conditions, and the accumulation of water and gas in the goaf in the secondary mining area; determine the development and deployment conditions such as the roadway layout and mining connection in the mine's secondary mining area; determine the underground mining method in the secondary mining area, including roadway layout, coal mining method, and technology; determine the underground coal transportation and auxiliary transportation methods through technical comparison and select supporting equipment for the newly added related equipment; analyze the gas emission volume and gas grade of the mine, calculate the mine air volume, distribute the air volume, calculate and check the mine negative pressure or select new ventilation equipment. (4)Division of the secondary mining area: Take the coal pillar as the partition boundary by analyzing the damage situation of the coal pillar in the old goaf; if there is no coal pillar, use grouting to form an artificial boundary. (5)Selection of mining technology: Select the complete set of comprehensive mining technology for old mined - out residual coal or the conventional wall - type comprehensive mining technology for residual coal recovery according to the mine conditions. (6)Safety pretreatment: Support and maintain the old goaf where the roof has not caved in, and discharge gas and drain water in advance. (7)Dynamic mining control: Use ground - penetrating radar to detect the coal body fracture zone in real - time, dynamically adjust the working face advancement parameters in combination with stress monitoring data, and monitor the gas concentration, water level of accumulated water, and ventilation negative pressure in the secondary mining area in real - time, and link and control the gas discharge equipment and drainage equipment. (8)System optimization design: Optimize the energy conservation of the underground power supply system, ventilation system, and dust removal system, and select high - efficiency equipment to reduce energy consumption. (9)Environmental protection treatment: Implement measures for dust suppression, sewage and wastewater treatment, noise control, and surface subsidence monitoring and repair.
[0011] In step (4), using grouting to form an artificial boundary specifically includes the following steps: According to the geological structure of the goaf, use high - pressure grouting equipment to inject grouting materials into the target area to form a continuous isolation belt, with the thickness of the isolation belt being 3 - 5 meters and the compressive strength ≥15 MPa.
[0012] The slurry material includes a cement-based composite material and a chemical hardening agent.
[0013] In step (9), the dust suppression measures include: installing a spray dust suppression device at the mining face and using a polymer dust suppressant to cover the coal dust diffusion area.
[0014] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement or combination made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A method for recovering residual coal resources in old goafs, characterized in that, It includes the following steps: (1) Mine overview and construction condition assessment: Collect and analyze the basic conditions of the mine, such as traffic location, topography, meteorology, surface and adjacent relations; comprehensively review the external construction conditions such as mine transportation conditions, power supply and communication conditions, water source conditions, and main building material supply conditions; comprehensively review the formation characteristics, geological structure, coal seam occurrence, hydrogeological overview and other resource conditions of the mine to determine that the internal conditions for project construction meet the construction requirements; (2) Determination of resource reserves and production capacity: According to the mine scale, geological conditions and the mining scope of old goafs, determine the mining resource reserves and designed production capacity of the mine's secondary mining area, and calculate the mining service life of the mine's secondary mining area; (3) Planning and deployment of the secondary mining area: Analyze the mine production and construction conditions such as the mine development method, level layout and district division, roadway layout and section, coal mining method, main production system, etc.; deeply investigate and understand the occurrence of coal resources, roof, water and gas accumulation in the goaf in the secondary mining area; determine the development and deployment conditions such as roadway layout and mining connection in the mine's secondary mining area; determine the underground mining method in the secondary mining area such as roadway layout, coal mining method and technology; determine the underground coal transportation and auxiliary transportation methods through technical comparison and select supporting equipment for new related equipment; analyze the gas emission volume and gas grade of the mine, calculate the mine air volume, distribute the air volume, calculate and check the mine negative pressure or select new ventilation equipment; (4) Division of the secondary mining area: Take the coal pillar as the partition boundary by analyzing the damage of the coal pillar in the old goaf; if there is no coal pillar, use grouting to form an artificial boundary; (5) Selection of mining technology: According to the mine conditions, select the complete set of fully mechanized mining technology for old residual coal or the conventional wall type fully mechanized mining technology for residual coal recovery; (6) Safety pretreatment: Support and maintain the old goaf with uncollapsed roof, and discharge gas and drain water in advance; (7) Dynamic mining control: Use ground penetrating radar to detect the coal body fracture zone in real time, dynamically adjust the working face advance parameters in combination with stress monitoring data, and monitor the gas concentration, water level and ventilation negative pressure in the secondary mining area in real time, and linkage control the gas discharge equipment and drainage equipment; (8) System optimization design: Optimize the energy conservation of the underground power supply system, ventilation system and dust removal system, and select high-efficiency equipment to reduce energy consumption; (9) Environmental protection treatment: Implement dust suppression, sewage and wastewater treatment, noise control and surface subsidence monitoring and repair measures.
2. The method for recovering residual coal resources in old goafs according to claim 1, characterized in that, In step (4), an artificial boundary is formed by grouting. Specifically, it includes the following steps: According to the geological structure of the goaf, use high-pressure grouting equipment to inject slurry materials into the target area to form a continuous isolation belt. The thickness of the isolation belt is 3 - 5 meters, and the compressive strength ≥ 15 MPa.
3. A method for recovering residual coal resources in old goafs according to claim 2, characterized in that: The slurry material includes cement-based composite materials and chemical reinforcing agents.
4. A method for re-mining residual coal resources in old goafs according to claim 1, characterized in that: In step (9), the dust suppression measures include: Installing spray dust suppression devices at the excavation and working faces, and using polymer dust suppressants to cover the coal dust diffusion area.