CN115127245A

CN115127245A - Geothermal energy efficient comprehensive utilization system applied to closed-pit mine

Info

Publication number: CN115127245A
Application number: CN202210791559.5A
Authority: CN
Inventors: 谭现锋; 陈洪年; 张丰; 宋帅良; 刘肖; 薄怀志; 孟甲; 史启朋
Original assignee: Shandong Lunan Geological Engineering Survey Institute of Second Geological Brigade of Shandong Geological Survey Bureau
Current assignee: Shandong Lunan Geological Engineering Survey Institute of Second Geological Brigade of Shandong Geological Survey Bureau
Priority date: 2022-07-05
Filing date: 2022-07-05
Publication date: 2022-09-30

Abstract

The invention provides a geothermal energy efficient comprehensive utilization system applied to a closed-pit mine, which comprises an energy station and the ground, wherein the energy station further comprises a plate exchanger, a heat pump, a desanding tank, a circulating pump and a constant-pressure water replenishing device, the plate exchanger, the heat pump and the desanding tank are sequentially bolted on the upper side inside the energy station from left to right, and the circulating pump and the constant-pressure water replenishing device are all bolted at the left end part and the right end part of the lower side inside the energy station. The energy storage pool is used for supplementing and adjusting a clean energy efficient utilization system, and the operation of the whole energy utilization system is not influenced by removing components of the system; the mechanical properties of surrounding rocks on the upper part of the system cannot be obviously changed due to the conduction of small micro-fractures, water flowing fractured zones, falling zones and the like to a water body and the balance of the water pumping and filling quantity of the whole application system; the upper and lower roadways, namely the roadway and the mining surface, belong to coal strata, the chemical components of surrounding rocks are similar, the water quality types are the same, and the water quality cannot be changed under the condition of balanced mining and filling.

Description

Geothermal energy efficient comprehensive utilization system applied to closed-pit mine

Technical Field

The invention belongs to the technical field of closed-pit mines, and aims to invent a geothermal energy efficient comprehensive utilization system applied to a closed-pit mine, which utilizes the existing closed-pit mine and the mine to be closed to develop and utilize geothermal resources, thereby changing waste into valuable; so that the abandoned mining roadway and mining face can be reused.

Background

Mine closure refers to mining of a mine which is mined after being emptied or is stopped due to unexpected reasons according to design.

At present, geothermal energy of a closed-pit mine is utilized and can be efficiently and comprehensively utilized again, so that the method is applied to a geothermal energy efficient comprehensive utilization system.

However, the existing geothermal energy efficient comprehensive utilization system also has the problems that energy waste is easily caused by excessive heat interaction, water quality is easily changed to influence the recycling effect, and the heat loss of a closed-pit mine causes resource waste and poor energy storage effect.

Therefore, the invention provides a geothermal energy efficient comprehensive utilization system applied to a closed pit mine, which is very necessary.

Disclosure of Invention

In order to solve the technical problems, the invention provides a geothermal energy efficient comprehensive utilization system applied to a closed-pit mine, wherein the geothermal energy efficient comprehensive utilization system is realized by the following technical scheme:

a geothermal energy efficient comprehensive utilization system applied to a closed-pit mine comprises an energy source station and the ground, wherein the energy source station further comprises a plate exchanger, a heat pump, a desanding tank, a circulating pump and a constant-pressure water replenishing device, wherein the plate exchanger, the heat pump and the desanding tank are sequentially bolted on the upper side of the inside of the energy source station from left to right, the circulating pump and the constant-pressure water replenishing device are both bolted on the left end part and the right end part of the lower side of the inside of the energy source station, and the energy source station is built on the ground;

the lower part of the energy station is also provided with a cooling taking pipe and a heating pipe, the cooling taking pipe is also branched and connected with a parallel pipeline to be connected with a public building house built on the right side of the ground, the cooling end of the agricultural building house and the agricultural planting and breeding base, and the heating pipe is also branched and connected with a parallel pipeline to be connected with the public building house, the heating end of the agricultural building house and the agricultural planting and breeding base.

Preferably, the left side of the inside of the ground is provided with an energy storage pool in a building manner, a water injection pump is arranged inside the energy storage pool, and a water injection pipe is connected to an outlet on the upper part of the water injection pump in a threaded manner.

Preferably, the water injection pump and the energy storage pool are connected through a pipeline.

Preferably, the left side and the right side of the energy station are both provided with a cooling pipe and a water replenishing pipe, wherein the lower end of the cooling pipe is arranged in the energy storage pool.

Preferably, the upper mining surface communication well and the lower mining surface communication well are arranged on the left side and the right side of the ground inside underground.

Preferably, the water injection pipe is arranged in the upper mining surface communication well.

Preferably, the lower end of the water replenishing pipe is in threaded connection with a submersible pump, the submersible pump is arranged inside the lower mining face communicating well, and the pipeline between the submersible pump and the lower mining face communicating well is communicated.

Preferably, the ground is divided into a bending deformation zone, a water guide fracture zone, an caving zone and a roadway and a mining surface, and the lower part of the roadway and the mining surface is divided into another layer of the bending deformation zone, the water guide fracture zone and the caving zone, wherein the upper surface of the other layer of the bending deformation zone is provided with an upper mining surface body, and the lower surface of the other layer of the mining surface is provided with a lower mining surface body.

Preferably, the ground is provided with a zero water line underground, wherein a water head pressure difference exists between the junction of the left side of the zero water line and the upper part of the upper mining face communicated well and the junction of the lower mining face communicated well.

Compared with the prior art, the invention has the beneficial effects that:

1. the energy storage pool is used for supplementing and adjusting a clean energy efficient utilization system, and the operation of the whole energy utilization system is not influenced by removing the system components.

2. According to the invention, because small micro-fractures, water diversion fracture zones, overflow zones and the like are communicated with a water body, and the whole pumping and filling water quantity of an application system is balanced, the mechanical properties of surrounding rocks on the upper part of the system cannot be obviously changed.

3. The upper and lower roadways, namely the roadway and the mining surface, belong to coal-series strata, the chemical components of surrounding rocks are similar, the water quality types are the same, and the water quality cannot be changed under the condition of balanced mining and irrigation.

4. According to the invention, different excavation surfaces are respectively utilized for heating in winter and cooling in summer, the water body temperature and the surrounding rock temperature after full utilization reach relative balance, energy waste caused by excessive heat interaction is avoided, and the sustainability is strong.

5. The water guide fractured zone formed by the mining space and the goaf left in the mining process is huge in space, and the clean energy utilization system has a wide development and utilization prospect.

6. The invention utilizes the existing closed pit and the mine to be closed to develop and utilize geothermal resources, thereby changing waste into valuable; so that the abandoned mining roadway and the mining face can be reused.

7. The invention fully utilizes the mining space of different positions, utilizes heat conduction media such as pit water and the like, and respectively adopts different modes to store and extract energy in different seasons.

8. According to shallow geothermal energy survey data, the temperature of the underground part-30 m is usually constant, the temperature is constant by about 15-19 ℃ according to different regions, the near-surface underground temperature-increasing gradient is about 1.8-3 ℃/100m, the temperature can reach 35 ℃ near the depth of 500-800 m, and a large number of mines have excavation surfaces at the depth, so that alternate energy-taking operation in winter and summer can be realized.

9. According to the invention, after the mine is closed, the excavation roadway and the chamber are filled with a large amount of water, different excavation surfaces are formed at different excavation depths of the mine, and hydraulic connection exists among the different excavation surfaces through small micro fracture cracks, artificial mining channels and the like; after the mine is closed, the goaf deforms and collapses to form a bending deformation zone, a water guiding crack zone and an caving zone, so that the connectivity of different mining surfaces is further improved, and the subsequent energy-taking effect in winter and summer is further ensured.

10. According to the general stratum development rule, the depth difference of two mining spaces of the coal-based stratum is generally more than 150m, and the temperature difference is 5 ℃ in a natural state; the long-term utilization of the system can expand the temperature difference to a certain extent; with the increase of the application years, the surrounding rock temperature of the upper mining space is reduced year by year and is consistent with the water body temperature, so that the energy storage effect is more excellent.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a schematic view of the winter energy storage mode structure of the present invention.

Fig. 3 is a schematic structural diagram of a summer energy-taking mode of the invention.

In the figure:

1. an energy source station; 2. a plate changer; 3. a heat pump; 4. a sand removal tank; 5. a circulation pump; 6. a constant-pressure water replenishing device; 7. taking a cold pipe; 8. a heating pipe; 9. a public building house; 10. agricultural building houses; 11. an agricultural planting and breeding base; 12. a ground surface; 13. an energy storage pool; 14. a water injection pump; 15. a water injection pipe; 16. a communicating well at the upper mining face; 17. a cooling tube; 18. a lower mining face communicating well; 19. a water replenishing pipe; 20. a submersible pump; 21. bending the deformation band; 22. a water-conducting fractured zone; 23. a falling belt; 24. roadways and mining surfaces; 25. an upper mining face body; 26. a lower mining face body; 27. a zero water line; 28. and breaking the crack.

Detailed Description

The invention is described in detail with reference to the accompanying drawings, as shown in fig. 1, a geothermal energy efficient comprehensive utilization system applied to a closed pit mine comprises an energy station 1 and a ground 12, wherein the energy station 1 further comprises a plate exchanger 2, a heat pump 3, a desanding tank 4, a circulating pump 5 and a constant pressure water replenishing device 6, wherein the plate exchanger 2, the heat pump 3 and the desanding tank 4 are sequentially bolted on the upper side inside the energy station 1 from left to right, the circulating pump 5 and the constant pressure water replenishing device 6 are both bolted on the left end part and the right end part of the lower side inside the energy station 1, and the energy station 1 is built on the upper part of the ground 12;

the lower part of the energy station 1 is also provided with a cooling taking pipe 7 and a heating pipe 8, the cooling taking pipe 7 is further branched and connected with a parallel pipeline to be connected with a public building house 9 built on the right side of the upper part of the ground 12, the agricultural building house 10 and the cooling end of the agricultural planting and breeding base 11, and the heating pipe 8 is further branched and connected with a parallel pipeline to be connected with the public building house 9, the agricultural building house 10 and the heating end of the agricultural planting and breeding base 11.

In this embodiment, specifically, the other layer of bending deformation belt 21 is further formed with breaking slits 28 on the left and right sides.

In this embodiment, specifically, the lower end of the upper face communication well 16 is located above the caving zone 23.

In this embodiment, the lower end of the lower face well 18 is located above the lower face body 26.

In this embodiment, specifically, when the upper mining surface communication well 16 is an inlet end arrow, and the lower mining surface communication well 18 is an outlet end arrow, the energy storage mode is the winter energy storage mode; conversely, when the upper working face communication well 16 is an outlet arrow, and the lower working face communication well 18 is an inlet arrow, the summer energy-taking mode is adopted.

In this embodiment, specifically, the plate exchanger 2, the heat pump 3 and the desanding tank 4 are connected in series through pipelines, the circulating pump 5 and the constant-pressure water replenishing device 6 are connected in series through pipelines, and the circulating pump 5 and the desanding tank 4 are connected in pipelines.

In this embodiment, specifically, the circulation pump 5 is connected to the cooling pipe 17, and the water replenishing pipe 19 is connected to the constant pressure water replenishing device 6.

In this embodiment, specifically, the cooling pipe 7 and the heating pipe 8 are both connected to the circulating pump 5 through a pipeline.

In this embodiment, as shown in fig. 2, geothermal water having a high temperature in the lower mining face body 26 and the tunnel is extracted as a circulation medium (about 30 to 40 degrees depending on the depth) through the upper mining face communication well 16 and the lower mining face communication well 18 in winter, and is supplied to the energy station 1, temperature extraction is performed by the plate exchanger 2 and the heat pump 3 in the energy station 1, and a temperature difference of 10 to 20 degrees centigrade in the circulation water can be extracted by the energy station 1, and this part of energy can be used for the winter heating operation of the public building house 9, the agricultural building house 10, and the agricultural planting and breeding base 11.

In this embodiment, as shown in fig. 2, the geothermal water after temperature extraction is cooled to 6-16 ℃, and is transported to the surface energy storage pool 13 for energy storage, the surface pool 31 can be modified by using the existing reservoir or mining area collapsed ponding area, in the energy storage pool 13, the circulating medium exchanges heat with the ambient temperature in winter, and absorbs the cold energy in the air for cold energy storage, so that the temperature is further reduced to 4-10 ℃, and the geothermal water is poured into the upper mining space.

In the embodiment, as shown in fig. 2, the temperature of the water injected into the upper excavation space is low, and in the semi-closed space, the cold energy can be stored to a certain degree, so that the temperature of the surrounding rock in the upper excavation space is gradually reduced.

In this embodiment, as shown in fig. 2, when heating is continued in winter and water in the lower excavation space is extracted and injected into the upper excavation space, a head pressure difference is formed between the upper excavation space and the lower excavation space, so that the water injected into the upper excavation space passes through the small bending deformation zone 21, and the water guide fractured zone 22 and the caving zone 23 replenish the water in the lower excavation space.

In the embodiment, the concrete implementation also includes that, as shown in fig. 3, the water injected into the upper mining space in winter has a certain loss of cold energy, and according to the monitoring data in north China, the water temperature rises by 2-6 ℃ and the temperature rise is higher when the temperature difference between the surrounding rock and the water is larger after local water-rock heat exchange for 4 months under the condition of insufficient flow.

In the embodiment, as shown in fig. 3, the average temperature of the water injected into the underground space is calculated to be 6 ℃, at this time, the temperature of the water in the upper mining space is about 8 to 12 ℃, the part of the water is extracted and conveyed to the energy station 1 for heat exchange, and the public building 9, the agricultural building 10 and the agricultural planting and breeding base 11 are refrigerated through heat exchange; the energy station 1 may extract energy at about 10-15 c.

In this embodiment, as shown in fig. 3, after energy extraction, the temperature of the circulating water reaches about 20 to 25 ℃, the circulating water is conveyed to the energy storage tank 13, and at this time, a layer of heat absorption film may be coated on the energy storage tank 13 to assist the water in storing heat, and the heat absorption film may be a common black plastic film or a higher-level medium; after absorbing the solar energy and the heat energy in the air, the water is injected into the lower mining space.

In this embodiment, as shown in fig. 3, the water head pressure difference between the lower excavation space and the upper excavation space is continuously used, and in this case, the water in the lower excavation space is supplied to the water in the upper excavation space through the small bending deformation zone 21, the water-flowing fractured zone 22, and the caving zone 23.

Principle of operation

In the invention, geothermal water with high temperature of a lower mining face body 26 and a tunnel is extracted as a circulating medium (the temperature is about 30-40 ℃ according to different depths) through an upper mining face communication well 16 and a lower mining face communication well 18 in winter and is conveyed to an energy station 1, temperature extraction is carried out through a plate exchanger 2 and a heat pump 3 device in the energy station 1, the temperature difference of 10-20 ℃ in the circulating water can be extracted through the energy station 1, the part of energy can be used for winter heating operation of a public building house 9, an agricultural building house 10 and an agricultural planting and breeding base 11, the geothermal water with the extracted temperature is cooled to 6-16 ℃ and is conveyed to an earth surface energy storage pool 13 for energy storage, the earth surface pool 31 can be transformed by utilizing the existing reservoir or mining area collapse accumulated water area, and the circulating medium exchanges heat with the ambient temperature in winter in the energy storage pool 13 to absorb cold energy in the air for energy storage, further reducing the temperature to 4-10 ℃, pouring the water into the upper mining space, calculating according to the average temperature of water injected into the underground space as 6 ℃, wherein the temperature of the water in the upper mining space is about 8-12 ℃, extracting the water and conveying the water to the energy station 1 for heat exchange, and refrigerating the public building 9, the agricultural building 10 and the agricultural planting and breeding base 11 through heat exchange; the energy station 1 can extract energy at about 10-15 ℃, the temperature of circulating water reaches about 20-25 ℃ after the energy is extracted, the circulating water is conveyed to the energy storage tank 13, a layer of heat absorption film can be coated on the energy storage tank 13 at the moment, the water is assisted to store heat, and the heat absorption film can be a common black plastic film or a higher-level medium; after absorbing solar energy and heat energy in the air, the water is injected into the lower mining space, and the water head pressure difference between the lower mining space and the upper mining space is continuously utilized, in this case, the water in the lower mining space is supplied to the water in the upper mining space through the small bending deformation zone 21, the water guide fractured zone 22 and the caving zone 23.

The technical solutions of the present invention or similar technical solutions designed by those skilled in the art based on the teachings of the technical solutions of the present invention are all within the scope of the present invention.

Claims

1. The efficient geothermal energy comprehensive utilization system applied to the closed-pit mine comprises an energy station (1) and the ground (12), and is characterized in that the energy station (1) further comprises a plate exchanger (2), a heat pump (3), a desanding tank (4), a circulating pump (5) and a constant-pressure water replenishing device (6), wherein the plate exchanger (2), the heat pump (3) and the desanding tank (4) are sequentially connected to the upper side of the inside of the energy station (1) through bolts from left to right, the circulating pump (5) and the constant-pressure water replenishing device (6) are both connected to the left end part and the right end part of the inside of the energy station (1) through bolts, and the energy station (1) is built on the upper part of the ground (12);

the energy station (1) is characterized in that a cooling taking pipe (7) and a heating pipe (8) are further arranged on the lower portion of the energy station (1), the cooling taking pipe (7) is further connected with a branch parallel pipeline to be built on a public building house (9) on the right side of the upper portion of the ground (12), the agricultural building house (10) and the agricultural planting and breeding base (11) are provided with cooling ends, the heating pipe (8) is further connected with a branch parallel pipeline to be connected with the public building house (9), and the agricultural building house (10) and the agricultural planting and breeding base (11) are provided with heating ends.

2. The system for high-efficiency comprehensive utilization of geothermal energy applied to the closed-pit mine according to claim 1, wherein an energy storage pool (13) is built on the left side inside the ground (12), a water injection pump (14) is arranged inside the energy storage pool (13), and a water injection pipe (15) is connected to an upper outlet of the water injection pump (14) in a threaded manner.

3. The system for the efficient comprehensive utilization of geothermal energy applied to the closed-pit mine according to claim 2, wherein the water injection pump (14) is connected with the energy storage pool (13) through a pipeline.

4. The system for comprehensively utilizing geothermal energy efficiently applied to the closed-pit mine according to claim 1, wherein the cooling pipes (17) and the water replenishing pipes (19) are arranged on the left side and the right side of the energy station (1), and the lower ends of the cooling pipes (17) are arranged inside the energy storage pool (13).

5. The system for comprehensive utilization of geothermal energy applied to the closed-pit mine according to claim 1, wherein the ground (12) is provided with an upper mining surface communication well (16) and a lower mining surface communication well (18) at the left and right sides of the underground inside.

6. The system for efficient and comprehensive utilization of geothermal energy applied to a closed-pit mine according to claim 2, wherein the water injection pipe (15) is disposed inside the upper face communication shaft (16).

7. The efficient geothermal energy comprehensive utilization system applied to the closed-pit mine according to claim 4, wherein the lower end of the water replenishing pipe (19) is connected with a submersible pump (20) in a threaded manner, the submersible pump (20) is arranged inside the lower mining surface communication well (18), and a pipeline is arranged between the submersible pump (20) and the lower mining surface communication well (18). .

8. The system for comprehensive utilization of geothermal energy applied to a closed-pit mine according to claim 1, wherein the ground (12) is divided into a bending deformation zone (21), a water-guiding fractured zone (22), an caving zone (23) and a roadway and mining surface (24) underground, and is further divided into another layer of the bending deformation zone (21), the water-guiding fractured zone (22) and the caving zone (23) under the roadway and mining surface (24), wherein the upper surface of the other layer of the bending deformation zone (21) is provided as an upper mining surface body (25), and the lower surface of the other layer of the mining surface (24) is provided as a lower mining surface body (26).

9. The system for efficiently and comprehensively utilizing geothermal energy applied to the closed-pit mine, as claimed in claim 1, wherein a zero water line (27) is arranged underground the ground (12), and a head pressure difference is formed between the junction of the left side of the zero water line (27) and the upper part of the upper mining surface communication well (16) and the junction of the lower part of the lower mining surface communication well (18).