Underground mine heat damage treatment and geothermal energy utilization combined system

Abstract

The utility model discloses an underground mine heat damage treatment and geothermal energy utilization combined system which is characterized in that a water inlet of a water supply pipeline (2) is connected with a cold water collecting pool (1), and the water supply pipeline (2) is arranged along a shaft to a deep middle section needing cooling; the heat exchange pipe network (16) is of a net-shaped structure which is composed of hollow metal heat exchange pipes and is communicated with one another, and the net-shaped structure is arranged along the side wall and the top of the deep middle-section roadway needing to be cooled. A water inlet of the water pump (8) is connected with a heat exchange pipe network water outlet (18) of a heat exchange pipe network (16) through a heat preservation pipe (9), and a water outlet of the water pump (8) is arranged along a shaft through the heat preservation pipe (9) to be discharged upwards to a ground surface heat exchanger (10) and finally enters a ground surface heating system. Cold water in the cold water collecting pool in the constant-temperature zone on the upper portion of the mine is fed into a deep middle section operation site needing to be cooled through the heat exchange pipe network, the environment temperature of the operation site is effectively controlled to be below the wet bulb temperature 27 DEG C, the environment temperature of a high-temperature operation area can be controlled, geothermal resources can be recycled, and the purpose of saving energy is achieved.

Description

Technical Field

[0001] This utility model belongs to the field of ventilation and cooling technology in underground mines, specifically relating to the treatment of thermal hazards in the surrounding rock of underground mines with high original rock temperature and the utilization of geothermal energy. Background Technology

[0002] The dissipation of heat from various heat sources within a mine causes the temperature to rise. As the depth of underground mining increases, the original rock temperature at the work site gradually rises; on average, the original rock temperature increases by 1-3°C for every 100 meters of increasing mining depth. The combined effects of high ground temperature and heat hazards from air compression, ore oxidation, mechanical equipment heat dissipation, and backfill hydration lead to a gradual increase in the temperature of the underground working environment. The problem of high temperature and humidity in the underground environment has become a major obstacle to the development of deep mineral resources. When the mine temperature exceeds a certain limit, it will affect the normal operation of underground work and the health of miners, reducing labor productivity and constituting mine heat hazards.

[0003] my country has the most heat-hazardous mines in the world. With increasing mining depth, heat hazards become increasingly prominent, necessitating corresponding mitigation measures to maintain a suitable underground working environment. Traditional mine cooling measures include both non-artificial and artificial cooling. Non-artificial cooling includes increased ventilation and personal protective equipment (PPE), but for mines with wet-bulb temperatures exceeding 35°C, increased ventilation significantly reduces its effectiveness, and energy consumption rises dramatically with increased airflow, resulting in poor economic efficiency. PPE requires workers to wear cooling vests, increasing their workload and hindering widespread adoption. Artificial cooling requires mechanical refrigeration units, which offer significant cooling effects, but these systems consume high amounts of electricity and struggle to adapt to the high vibration, high dust, and dynamically changing environment caused by underground blasting. The system's construction and operating costs are high, and its lifespan is short, making it unaffordable for most mining companies.

[0004] The article "Analysis and Prevention Measures of High-Temperature Heat Hazards in Deep Mining" published in the 4th issue of the Chinese journal *Shandong Coal Industry Science and Technology* in 2016 proposed several effective pre-cooling heat hazard prevention measures, including increasing air volume, changing ventilation methods, controlling heat sources, surface air conditioning, and centralized underground cooling. These measures provide suggestions and options for heat hazard management during mine construction and production, and offer valuable lessons for other related mines. However, these measures either have limited cooling effects or involve significant investment and high costs.

[0005] The temperature field extending from the surface to depth in a mine can be divided into three zones: a variable temperature zone, a constant temperature zone, and a warming zone. Deep, high-temperature mining operations are typically located in the warming zone. However, in the early stages of underground mining, some sections are often situated in the variable temperature zone and the constant temperature zone. The original rock temperature in these areas is relatively low. The temperature in the constant temperature zone is approximately equal to the average annual air temperature of the mine's location. The temperature of the water flowing into the tunnels in the constant temperature zone is much lower than the ambient temperature at depth, providing a natural cooling medium and heat exchanger for heat hazard management in deep mining areas. Summary of the Invention

[0006] The purpose of this utility model is to address the prominent problems of heat hazards in deep mines, the harsh working environment for workers, resulting in low labor efficiency and significant safety hazards, as well as the technical problems of existing ventilation and cooling systems, such as high investment, high operating costs, poor cooling effect, high system energy consumption, and short equipment lifespan. The proposed system is a combined underground mine heat hazard management and geothermal energy utilization system that is simple in structure, reliable in operation, has a good cooling effect, and can convert heat hazards into geothermal resources.

[0007] To achieve the above-mentioned objectives of this utility model, the following technical solution is adopted for the combined system of underground mine heat hazard control and geothermal energy utilization:

[0008] This utility model discloses a combined system for underground mine heat hazard control and geothermal energy utilization. It includes a cold water collection tank and water supply pipelines, a heat exchange network, a water pump, insulated water pipes, and a surface heat exchanger located within the constant temperature zone of the upper mine shaft. The cold water collection tank collects cold water from the upper part of the mine. The water supply pipeline inlet is connected to the cold water collection tank. The water supply pipeline is arranged along the shaft down to the deep section requiring cooling and is connected in series with a pressure regulating valve and a filter. The outlet of the filter is connected to the inlet of the heat exchange network. The heat exchange network is a mesh structure composed of hollow metal heat exchange tubes that are interconnected. The heat exchange network is arranged along the sidewalls and top of the deep roadway sections that need cooling. The water pump inlet is connected to the heat exchange network outlet via an insulated pipe. The water pump outlet is discharged upwards through an insulated water pipe arranged along the well shaft to the surface heat exchanger, and finally enters the surface heating system. The high-temperature hot water that absorbs geothermal energy underground is discharged upwards through the well shaft via the water pump and insulated water pipe to the surface, where it enters the surface heat exchanger for use.

[0009] In order to regulate the cold water supply and downhole temperature, this utility model also includes a monitoring system, which consists of a surface main control unit, an inlet flow meter, a first water thermometer, an outlet flow meter, and a second water thermometer. The inlet flow meter is installed on the water supply pipe next to the inlet of the heat exchange pipe network, and the outlet flow meter is installed on the water supply pipe next to the outlet of the heat exchange pipe network. The first water thermometer is installed on the water supply pipe between the inlet flow meter and the inlet of the heat exchange pipe network, and the second water thermometer is installed on the water supply pipe between the outlet of the heat exchange pipe network and the outlet flow meter. The surface main control unit is connected to the inlet flow meter, the first water thermometer, the outlet flow meter, and the second water thermometer via communication cables.

[0010] Preferably, a pressure gauge is installed on the water supply pipe between the pressure regulating valve and the filter, and the ground control unit is connected to the pressure gauge via a communication cable.

[0011] Preferably, the diameter of the heat exchange network is 3.5-5cm, with 4cm being the most preferred.

[0012] Furthermore, the heat exchange network is composed of multiple heat exchange network units assembled in sections along the axis of the deep section of the roadway that needs to be cooled. The length of each section is equal to the length of one cycle of the blasting roadway, and the width of each section is 1.5-2m. The outlets and inlets between adjacent sections are tightly connected by quick connectors.

[0013] Preferably, the heat exchange pipeline network is assembled in sections along the tunnel axis. Each section is equal in length to the length of one cycle of tunnel excavation, and each section is 1.5-2m wide. The inlets and outlets of adjacent sections are tightly connected by quick-connect couplings. Each section is quickly connected to the preceding section via a pre-reserved quick-connect interface. The new pipeline inlet is connected to the outlet of the preceding pipeline, and the new pipeline outlet is connected to the water supply network of the heat recovery system.

[0014] The pressure gauge of this utility model is equipped with a pressure sensor, and the first water thermometer and the second water thermometer are respectively equipped with temperature sensors.

[0015] The combined system for underground mine heat hazard control and geothermal energy utilization of this utility model, after adopting the above-mentioned technical solution, has the following beneficial effects:

[0016] (1) The cold water in the cold water collection pool in the constant temperature zone above the mine is supplied to the deep intermediate section of the work site that needs to be cooled through the heat exchange pipeline network, so that the ambient temperature of the work site can be effectively controlled below the wet bulb temperature of 27°C, and the ambient temperature of the work site can be further reduced as the temperature of the cold water supplied in the heat exchange pipeline network decreases.

[0017] (2) Through the heat exchange effect of the heat exchange network, the water temperature difference between the inlet and outlet of the heat exchange network can reach more than 10℃. As the length of the network increases, the water temperature at the outlet of the heat exchange network gradually increases, reaching the original rock temperature at the location of the tunnel.

[0018] (3) It has achieved effective control of underground heat hazards and recovered geothermal energy. The cost of ventilation and cooling is reduced by more than 80% compared with traditional cooling and ventilation cooling, and its system has higher stability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structural connection of a combined system for underground mine heat hazard control and geothermal energy utilization according to this utility model;

[0020] Figure 2 This is a schematic diagram of the structure of the heat insulation support and heat exchange system S arranged on the top and wall of the excavated tunnel in this embodiment of the utility model.

[0021] Figure 3 yes Figure 2 Longitudinal section view along the AA direction.

[0022] The attached diagram is labeled as follows: 1-Cold water collection tank; 2-Water supply pipe; 3-Pressure regulating valve; 4-Filter; 5-Inlet flow meter; 6-First water thermometer; 5'-Outlet flow meter; 6'-Second water thermometer; S-Insulation support and heat exchange system; 8-Water pump; 9-Insulated water pipe; 10-Surface heat exchanger; 11-Surface main control unit; 12-Communication cable; 13-Pressure gauge; 14-Ordinary concrete support layer; 15-Insulation support concrete; 16-Heat exchange pipe network; 17-Heat exchange pipe network inlet; 18-Heat exchange pipe network outlet; 19-Original rock surface of the tunnel. Detailed Implementation

[0023] To further describe this utility model, the following detailed description of a combined system for controlling heat hazards in underground mines and utilizing geothermal energy is provided in conjunction with the accompanying drawings.

[0024] Depend on Figure 1 The diagram shown is a structural connection diagram of a combined system for underground mine heat hazard control and geothermal energy utilization according to this utility model, and is combined with... Figure 2 , Figure 3As can be seen, the present invention provides a combined system for underground mine heat hazard control and geothermal energy utilization, including a cold water collection tank 1 and a water supply pipeline 2, a heat exchange network 16, a water pump 8, an insulated water pipe 9, a surface heat exchanger 10, and a monitoring system located in the constant temperature zone of the upper part of the mine. The inlet of the water supply pipeline 2 is connected to the cold water collection tank 1. The water supply pipeline 2 is arranged along the shaft down to the middle section of the deep part that needs to be cooled and is connected in series with a pressure regulating valve 3 and a filter 4. The outlet of the filter 4 is connected to the inlet 17 of the heat exchange network 16. A pressure gauge 13 is installed on the water supply pipeline 2 between the pressure regulating valve 3 and the filter 4. The surface main control unit 11 is connected to the pressure gauge 13 through a communication cable 12. The heat exchange network 16 is a mesh structure composed of interconnected hollow metal heat exchange tubes. It is assembled in sections along the axis of the deep, cooling section of the roadway. Each section is equal in length to the length of one cycle of the blasting tunnel and 1.5-2m wide. The inlets and outlets of adjacent sections are tightly connected by quick-connect couplings. The heat exchange network 16 is arranged along the sidewalls and top of the deep, cooling section of the roadway. The inlet of the water pump 8 is connected to the outlet 18 of the heat exchange network 16 via an insulated pipe 9. The outlet of the water pump 8 is discharged upwards along the well shaft via an insulated water pipe 9 to the surface heat exchanger 10, and finally into the surface heating system. The monitoring system consists of a surface main control unit 11, an inlet flow meter 5, a first water thermometer 6, and an outlet flow meter 5. ’ Second water thermometer 6 ’ Composition: The inlet flow meter 5 is installed on the water supply pipe 2 next to the inlet 17 of the heat exchange pipe network, and the outlet flow meter 5... ’ The first water thermometer 6 is installed on the water supply pipe 2 next to the outlet 18 of the heat exchange pipe network; the second water thermometer 6 is installed on the water supply pipe 2 between the inlet flow meter 5 and the inlet 17 of the heat exchange pipe network. ’ Installed at the outlet 18 of the heat exchange pipeline and the outlet flow meter 5 ’ On the water supply pipe 2 between them; the surface main control unit 11 is connected to the inlet flow meter 5, the first water thermometer 6 and the outlet flow meter 5 respectively via communication cable 12. ’ Second water thermometer 6 ’ connect.

[0025] Depend on Figure 2 The diagram shown below illustrates the structure of the heat insulation support and heat exchange system S arranged on the top and walls of the excavated tunnel in this embodiment of the present invention, combined with... Figure 1 , Figure 3As can be seen, the heat insulation support and heat exchange system S is arranged along the roadway direction, including an ordinary concrete support layer 14, a heat exchange pipe network 16, and heat insulation support concrete 15. The ordinary concrete support layer 14 is formed by spraying ordinary concrete with a thickness of not less than 10cm onto the original rock surface 19 of the excavated roadway. The heat exchange pipe network 16 is laid on the ordinary concrete support layer 14. The heat insulation support concrete 15 is formed by spraying heat insulation concrete with a thickness of 10cm onto the ordinary concrete support layer 14 and the heat exchange pipe network 16. The heat exchange pipe network 16 is a mesh structure composed of hollow metal heat exchange pipes with a diameter of 4cm and a very fast thermal conductivity, which are connected to each other and attached to the sidewalls and top of the roadway along the surface of the ordinary concrete support layer 14. The heat exchange pipe network 16 is assembled in sections along the tunnel axis. Each section is equal in length to the length of one cycle of tunnel excavation, and 1.5-2m wide. The inlets and outlets of adjacent sections are tightly connected by quick-connect couplings. Specifically, each section is quickly connected to the preceding section via a pre-reserved quick-connect interface. The new pipe network inlet connects to the outlet of the preceding pipe network, and the new pipe network outlet connects to the heat recovery system's water supply network. The cold water in the heat exchange pipe network 16 absorbs the heat continuously released from the surrounding tunnel, preventing its propagation into the tunnel air. The insulation system, composed of the ordinary concrete support layer 14 and the heat-insulating support concrete 15, provides a sealed and tight heat exchange condition for the heat exchange pipe network 16. It also further prevents heat not absorbed by the low-temperature water in the pipe network from propagating into the tunnel air, allowing the heat to be gradually absorbed by the cold water in the heat exchange pipe network, thereby reducing the tunnel temperature.

[0026] As the length of the heat exchange network 16 increases and the pipe resistance rises, the water pressure in the water supply pipe 2 will be insufficient to guarantee the water flow rate in the heat exchange network 16. Therefore, a lower limit alarm value for the flow rate is set in the monitoring system. When the flow rate in the heat exchange network 16 is less than the lower limit alarm value, the monitoring system sends a command to the pressure regulating valve 3 to adjust the water pressure in the water pipe and ensure the stability of the system water volume; based on the first water thermometer 6 and the second water thermometer 6... ’ Based on the temperature difference and the flow rate of the flow meter, the heat exchange capacity of the insulation support and heat exchange system S is calculated; based on the flow difference between the inlet flow meter 5 and the outlet flow meter 5', the presence of leakage in the insulation support and heat exchange system S is monitored.

[0027] Let the flow rate of inlet flow meter 5 be m, the temperature of the first water thermometer 6 be T1, and the temperature of the second water thermometer 6 be... ’ If the temperature is T2 and the specific heat capacity of water is c, then the heat collected by the insulation support and heat exchange system S is calculated according to the following formula: Q=c*m*(T2-T1).

Claims

1. A combined system for underground mine heat hazard control and geothermal energy utilization, characterized in that: It includes a cold water collection tank (1) and water supply pipeline (2), heat exchange pipeline (16), water pump (8), insulated water pipe (9), and surface heat exchanger (10) located in the constant temperature zone of the upper part of the mine. The inlet of the water supply pipeline (2) is connected to the cold water collection tank (1). The water supply pipeline (2) is arranged along the shaft down to the middle section where cooling is required and is connected in series with the pressure regulating valve (3) and the filter (4). The outlet of the filter (4) is connected to the heat exchange pipeline of the heat exchange pipeline (16). Water inlet (17) connection; the heat exchange network (16) is a mesh structure composed of hollow metal heat exchange tubes that are interconnected. The heat exchange network (16) is arranged along the side wall and top of the deep section of the roadway that needs to be cooled; the water inlet of the water pump (8) is connected to the heat exchange network outlet (18) of the heat exchange network (16) by the heat-insulated water pipe (9), and the water outlet of the water pump (8) is arranged along the well shaft by the heat-insulated water pipe (9) and discharged to the surface heat exchanger (10), and finally enters the surface heating system.

2. The combined system for underground mine heat hazard control and geothermal energy utilization as described in claim 1, characterized in that: It is also equipped with a monitoring system, which consists of a surface main control unit (11), an inlet flow meter (5), a first water thermometer (6), and an outlet flow meter (5). ’ ), second water thermometer (6) ’ Composed of: an inlet flow meter (5) installed on the water supply pipe (2) next to the inlet (17) of the heat exchange pipe network, and an outlet flow meter (5) ’ The first thermometer (6) is installed on the water supply pipe (2) next to the outlet (18) of the heat exchange network; the second thermometer (6) is installed on the water supply pipe (2) between the inlet flow meter (5) and the inlet (17) of the heat exchange network. ’ ) Installed at the outlet of the heat exchange pipeline (18) and the outlet flow meter (5) ’ On the water supply pipe (2) between the two; the surface main control unit (11) is connected to the inlet flow meter (5), the first water thermometer (6) and the outlet flow meter (5) respectively via communication cable (12). ’ ), second water thermometer (6) ’ )connect.

3. A combined system for underground mine heat hazard control and geothermal energy utilization as described in claim 1 or 2, characterized in that: A pressure gauge (13) is installed on the water supply pipe (2) between the pressure regulating valve (3) and the filter (4), and the ground main control unit (11) is connected to the pressure gauge (13) via a communication cable (12).

4. The combined system for underground mine heat hazard control and geothermal energy utilization as described in claim 3, characterized in that: The diameter of the heat exchange network (16) is 3.5-5cm.

5. The combined system for underground mine heat hazard control and geothermal energy utilization as described in claim 4, characterized in that: The heat exchange network (16) is composed of multiple heat exchange network units assembled in sections along the axis of the deep section of the roadway that needs to be cooled. The length of each section is equal to the length of one cycle of the blasting roadway, and the width of each section is 1.5-2m. The outlet and inlet of adjacent sections are tightly connected by quick connectors.

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