WO2020087880A1

WO2020087880A1 - Semi-underground pumped-storage hydroelectric power station employing open-pit mine, and method for constructing same

Info

Publication number: WO2020087880A1
Application number: PCT/CN2019/083199
Authority: WO
Inventors: 何满潮; 孙晓明; 郭平业
Original assignee: 中国矿业大学(北京)
Priority date: 2018-10-30
Filing date: 2019-04-18
Publication date: 2020-05-07
Also published as: CN109518665A

Abstract

A semi-underground pumped-storage hydroelectric power station employing an open-pit mine, and a method for constructing the same. The power station comprises a high-level water storage region and a low-level water storage region (20), a water delivery channel (15), and a bidirectional generator. The water delivery channel (15) communicates with the high-level water storage region and the low-level water storage region (20) and is disposed therebetween. The bidirectional generator is disposed between the high-level water storage region and the low-level water storage region (20), and is configured to generate pumped-storage hydroelectric power or electricity using water from the water delivery channel (15). The present method for constructing a semi-underground pumped-storage hydroelectric power station utilizes both the aboveground space and underground space of an abandoned mine, such that an open pit of the abandoned mine serves as a high-level water storage region, and tunnels of the abandoned mine serve as an underground water storage region.

Description

Semi-underground pumped storage power station based on open pit and its forming method

Cross-reference of related applications

This disclosure claims priority based on the Chinese application with the application number 201811280511.8 filed on October 30, 2018, the entire contents of which are incorporated herein by reference.

Technical field

The present disclosure relates to the fields of mining engineering and water conservancy engineering, and in particular to a semi-underground pumped storage power station based on open pits and its formation method.

Background technique

With the depletion of coal resources and the impact of China's energy structure adjustment and other factors, a large number of mines have been closed for scrapping or entered a scrapping transition stage. According to statistics, by the end of 2015, the number of scrapped coal mines in China reached 2,888. The mine caves left after the coal mine is scrapped generally have the characteristics of large space, different depths, different height differences, and sufficient water sources. These conditions are just favorable conditions for the construction of pumped storage power stations.

Most of China's coal mines are located in the northern region. Due to the limitation of topography, the location of the northern region has always troubled the construction of pumped storage power stations. The use of abandoned mines to build energy storage power stations is a promising way of energy storage. It is not only beneficial to widen the range of energy storage points, make the site closer to the load center, new energy base, UHV line intersection, etc., and promote the safety of the power grid. Stable operation, and can form a new energy micro-grid system according to the energy development situation of the mining area, so that the mining area can be transformed from a large industrial water and electricity consumer to a new energy power output; at the same time, the use of energy storage in the mine can reduce the amount of dam construction and land acquisition Expenses, alleviate the problem of water source evaporation, and effectively save project investment; in addition, it can promote the restoration of the natural ecological environment of the mining area, drive the development of related industries in the surrounding area, and realize the transformation of waste into treasure. Environmental and social benefits.

However, the construction of pumped-storage power stations using abandoned mines is different from traditional pumped-storage power stations. Influenced by geology, environment, and equipment, the location of the reservoir and the layout of the power station affect the stability and economic benefits of the entire power station. In addition, Since the pumped storage power station usually needs to be installed about 500-1000 meters underground, it also brings many restrictions on the layout of large-scale units in the underground.

Therefore, there is an urgent need for a new pumped storage power station and its formation method to optimize its operation mode.

Summary of the invention

The purpose of the present disclosure is to provide a semi-underground pumped storage power plant based on open pits and its formation method. The semi-underground pumped storage power station based on open pits uses abandoned mines as the underground space for pumped storage, while using the open pits of abandoned mines as the aboveground space for pumped storage, and designs high-level water storage with different levels of height difference Area and low-level water storage area, so as to use the semi-underground pumped storage power station to achieve a positive ecological and economic win-win for pumping and turning waste mines into treasure.

In order to achieve the above purpose, the present disclosure adopts the following technical solutions:

According to an aspect of the present disclosure, a semi-underground pumped storage power plant based on an open pit is provided. Wherein, the semi-underground pumped-storage power plant based on open pits includes: a high-level water storage area and a low-level water storage area, a water delivery channel and a bidirectional generator set. The water conveyance channel is connected between the high water storage area and the low water storage area. The two-way generator set is disposed between a high-level water storage area and a low-level water storage area, and the two-way generator set is used to pump water through the water delivery channel to store energy or generate electricity. Wherein, the high-level water storage area is an open pit of the abandoned mine, and the low-level water storage area is an underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.

According to one embodiment of the present disclosure, the underground space of the abandoned mine shaft includes a roadway, a mined-out area, and a shaft, an underground water storage area is built in the roadway, and a water delivery channel is built in the shaft.

According to one embodiment of the present disclosure, at least one side of each underground water storage area is provided with a blocking wall, and the blocking wall is provided with a control valve.

According to one embodiment of the present disclosure, the height difference between the high-level water storage area and the low-level water storage area is less than the highest lift of the bidirectional generator set.

According to one embodiment of the present disclosure, the height difference between the high water storage area and the low water storage area is 200-400 m.

According to one of the embodiments of the present disclosure, it further includes a solar and / or wind energy power generation device, and the solar and / or wind energy power generation device and a semi-underground pumped storage power plant based on an open pit form a wind-solar power generation complementary system.

According to one embodiment of the present disclosure, it further includes a middle water storage area, the middle water storage area is located between the high water storage area and the low water storage area, and the water delivery channel communicates with the high water storage area and the middle water storage area Between the middle water storage area and between the middle water storage area and the low water storage area, the two-way generator set is arranged between the high water storage area and the middle water storage area, and the middle water storage Between the water storage area and the low water storage area; wherein the middle water storage area and the low water storage area are the underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.

According to another aspect of the present disclosure, there is provided a method for forming a semi-underground pumped storage power plant based on an open pit as described above, including the following steps:

Open pits that reinforce abandoned mine shafts are used as high-level water storage areas;

Determine the properties of surrounding rocks, select abandoned mine roadways with stable surrounding rock characteristics to construct underground water storage areas, and construct at least low water storage areas with height differences as underground water storage areas;

Construct a water conveyance channel connecting the high water storage area and the low water storage area in the abandoned mine shaft, and set up a bidirectional generator set between the high water storage area and the low water storage area;

The two-way generator set is used to raise or drain water between the high-level water storage area and the low-level water storage area through the water conveyance channel for pumping and energy storage.

According to one embodiment of the present disclosure, it is characterized by the following steps:

Construct a middle water storage area between the high water storage area and the low water storage area;

Construct a water delivery channel in the abandoned mine shaft that connects the high water storage area and the middle water storage area, and the middle water storage area and the low water storage area, and between the high water storage area and the middle water storage area, and Two-way generators are set between the middle water storage area and the low water storage area respectively;

The two-way generator set is used to carry out cascade pumping and storage by stepping pumping or drainage between the high water storage area and the middle water storage area, and the middle water storage area and the low water storage area through the water transmission channel.

According to one embodiment of the present disclosure, the goaf of the abandoned mine is a reserve water storage area.

The "abandoned mine" mentioned in the present disclosure refers to a mine that has ceased operation after mining or an abandoned underground working surface in the mine that is being mined.

As can be seen from the description of the above technical solutions, the beneficial effects of the present disclosure are:

By designing water storage areas with different height differences and using the formed step height difference to convert potential energy to electrical energy, the reliability and stability of pumped storage are improved;

By disposing two-way generator sets on the water conveyance channels between the water storage areas, the problem that the underground space of the traditional water storage and storage power station is too deep, which restricts the layout of large units, is effectively solved.

By making full use of the above-ground and underground spaces of abandoned mines, it has promoted the restoration of the natural ecological environment of the mining area, driven the development of surrounding industries, and realized the transformation of waste into treasure; using the open-pit mine formed after mining as a high-level water storage area can also reduce construction Dam engineering volume and land acquisition costs effectively save project investment; in short, the semi-underground pumped storage power station based on open pits of the present disclosure effectively expands the storage energy selection range, so that the site can be directed to the load center, new energy base, The intersection of UHV lines is close to promote the safe and stable operation of the power grid, and can form a new energy micro-grid system according to the energy development situation of the mining area, which transforms the mining area from a large industrial water and electricity consumer to a new energy power output place with a prominent environment And social benefits.

BRIEF DESCRIPTION

1 is a process diagram of a method for forming a semi-underground pumped storage power station based on an open pit according to an embodiment of the present disclosure;

2 is a schematic diagram of the space of a semi-underground pumped storage power station based on an open pit according to an embodiment of the present disclosure;

3 is a plan layout diagram of a central storage area and a low storage area, equipment layout, and anti-blocking measures of a semi-underground pumped storage power station based on an open pit according to an embodiment of the present disclosure;

4 is a cross-sectional view of an arrangement diagram of a semi-underground pumped storage power station based on an open pit according to an embodiment of the present disclosure;

Among them, the reference signs are described as follows:

1: ground surface

2: Wind energy;

3: Power grid;

4: Solar energy;

5: Water pipeline well;

6: Pedestrians and power transmission wells;

7a: Neutral bidirectional generator set;

7b: Low-level bidirectional generator set;

8: Middle reservoir;

9: rock formation;

10: block the wall;

11: mining roadway;

12: Water-bearing rock formation;

13: Water-proof rock layer;

14: Transmission line;

15: Water delivery channel;

16: Lower reservoir;

17: Goaf area;

18: Open pit

19: median water storage area;

20: Low water storage area.

detailed description

The technical solution of the present disclosure will be further described below according to specific embodiments. The scope of protection of the present disclosure is not limited to the following embodiments, and these examples are listed for illustrative purposes only and do not limit the present disclosure in any way.

The present disclosure provides a semi-underground pumped storage power station based on open pits, including:

High water storage area and low water storage area;

The water conveyance channel is connected between the high water storage area and the low water storage area; and

The two-way generator set is arranged between the high-level water storage area and the low-level water storage area, and uses the two-way generator set to pump water to store energy or generate electricity through the water delivery channel;

Wherein, the high-level water storage area is an open pit of the abandoned mine, and the low-level water storage area is an underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.

Specifically, the abandoned mine generally includes stable roadways, goafs, shafts, unstable spaces, recovery roadways, etc. The underground storage area of semi-underground pumped storage power stations based on open pits is not affected by mining and Stable roadway with good surrounding rock conditions. Furthermore, the high-level water storage area may use open pits of abandoned mine shafts. The open pit refers to the open-pit mining area during mine mining. It can be further strengthened by measuring the range of the open-pit and the volume of water source, etc., so that the open-pit can be used as a high-level storage of semi-underground pumped storage power station based on the open-pit The water area is the upper reservoir.

Further, the original shaft of the abandoned mine can be used as a pedestrian and power transmission well and water pipeline well of the semi-underground pumped storage power station based on the open pit, used for installing water transmission channels, transmission lines or as pedestrian channels, etc., to make full use of Underground space in abandoned mine.

Further, the high-level water storage area and the low-level water storage area may be respectively provided with blocking walls on at least one side thereof, and the blocking wall separates each water storage area from the unstable space and / or goaf in the same plane for use In order to block the connection between the underground water storage space of the abandoned mine and the unstable space, the plugging wall material may be plugged with reinforced concrete, and the plugging measures and techniques use techniques well known in the art. In addition, the present disclosure can also establish an adjustable channel for the underground water storage space and the upper water-bearing rock layer; furthermore, a control valve is installed on the plugging wall, and the connection between the underground water storage space and the mined-out area is established through the control valve. When the water flow enters the mined-out area under the influence of mining, the control valve can ensure a controllable connection between the underground water storage space and the mined-out area (water content), and ensure the supply of water during the energy storage process. Preferably, the control valve may be a one-way valve, so that the water in the water storage area does not flow to the goaf area.

Further, the height difference between the high-level water storage area and the low-level water storage area is less than the highest lift of the bidirectional generator set. Furthermore, the height difference between the high-level water storage area and the low-level water storage area is 200-400 m. By designing such a semi-underground water storage area with height difference distribution, the present disclosure makes the arrangement of the generating units located in each water storage area not limited to the depth of the semi-underground pumped storage power station based on open pits, reducing the power generation unit ’s Difficulty in layout.

Further, the present disclosure can output current through an external power supply for pumping and storage of a bidirectional generator set, or provide solar and / or wind energy devices, and form a complementary system of wind and solar power generation with a semi-underground pumped storage power station based on an open pit. The wind-solar power generation complementary system can make full use of the complementarity of wind and light resources in time distribution, can output stable and highly reliable electric energy, and reduce the impact on the power grid during grid connection.

Further, the present disclosure may also preferably include a middle water storage area, the middle water storage area is located between the high water storage area and the low water storage area, and the water conveyance channel communicates between the high water storage area and the middle water storage area Between the middle water storage area and the low water storage area. The bidirectional generator set is arranged between the high water storage area and the middle water storage area, and between the middle water storage area and the low water storage area. Among them, the high water storage area, the middle water storage area and the low water storage area are used as the underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.

Further, the central water storage area may also be provided with a blocking wall on at least one side thereof, and the blocking wall separates the central water storage area from the unstable space and / or goaf in the same plane for blocking The connection between the underground water storage space of the abandoned mine and the unstable space, the plugging wall material can be plugged with reinforced concrete, and the plugging measures and techniques use techniques well known in the art. In addition, the present disclosure can also establish an adjustable channel for the underground water storage space and the upper water-bearing rock layer; further, a control valve is installed on the plugging wall, and the control valve is used to establish a connection between the central water storage area and the mined-out area. When the water flow enters the mined-out area under the influence of mining, the control valve can ensure the controllable connection between the underground water storage space and the mined-out area (water content), and guarantee the supply of water during the energy storage process. Preferably, the control valve may be a one-way valve, so that the water in the water storage area does not flow to the goaf area.

Further, the height difference between the high-level water storage area, the middle-level water storage area and the low-level water storage area is less than the highest lift of the bidirectional generator set. Furthermore, the height difference between the high water storage area and the middle water storage area is 200-400m, and the height difference between the middle water storage area and the low water storage area may also be 200 ~ 400m. The present disclosure reduces the depth of fully underground pumped-storage power stations by designing such underground water storage areas with height difference distribution, which are all located in the underground space of abandoned mine shafts, so that the arrangement of generator units located in each water storage area Difficulty in generating unit layout. The present disclosure also provides a method for forming a semi-underground pumped storage power plant based on an open pit as described above, including the following steps:

Specifically, the method for determining the properties of the surrounding rock includes: measuring the water-bearing rock layer, the water-bearing rock layer, and the distribution of the water flow field of the abandoned mine by drilling, sonic detection, and isotope measurement to obtain the water-bearing rock layer and the water-bearing rock layer Distribution, according to on-site observation and theoretical analysis of the influence of aquifers, the risk factors and management measures for the middle and low water storage areas are obtained. Based on the data obtained, the properties of the surrounding rock of the mine were further measured, and the abandoned mine roadway with stable surrounding rock characteristics was selected as the low-level water storage area of the semi-underground pumped storage power station based on the open pit of the abandoned mine. In addition, the layout of the high-level water storage area is to determine the open-pit pit as the high-level water storage area by measuring the scope of the open pit, the volume of the water source and the water supply replenishment time node.

Further, when an open pit is used as a high-level water storage area, the open pit's range, water source volume and water supply replenishment time nodes need to be measured, and the open pit is used as a high-level water storage area according to the obtained data. The detection methods include: detecting the range of open pits and water source volume caused by mining through earth remote sensing technology; establishing a long-term ground and satellite joint observation system, analyzing and analyzing the evolution of the upper water level of open pits forming the open pits, and determining the water supply time node. According to the obtained data, the open pit is strengthened as a high-level water storage area of the semi-underground pumped storage power station based on the open pit, that is, the upper reservoir; the open pit reinforcement mainly includes slope reinforcement and anti-seepage design to ensure the safety of the upper reservoir formed by the open pit And the volume of water source is stable.

Further, the method for forming a semi-underground pumped storage power station based on an open pit proposed by the present disclosure may also preferably include the following steps:

Further, it also includes using the mined-out area of the abandoned mine as a backup water storage area. When the goaf of the abandoned mine is affected by mining, water can be established by establishing a connection between the goaf and the stable roadway of the abandoned mine, so as to ensure the supply of water to the underground water storage area during energy storage.

The following is a specific example:

FIG. 1 is a process diagram of a method for forming a semi-underground pumped storage power plant based on an open pit according to an embodiment of the present disclosure. The semi-underground pumped storage power plant based on an open pit uses an abandoned mine as an underground space and an open mine with an abandoned mine as an The high water storage area includes the following steps:

A. Measure the open pit range and water source volume caused by mining through earth remote sensing technology, establish a long-term ground and satellite joint observation system, analyze and analyze the evolution of the horizontal level of the upper reservoir formed by the open pit, determine the water supply time node, and strengthen the open air according to the obtained data The mine pit serves as a high-level water storage area for semi-underground pumped storage power stations based on open pits;

B. Measure the distribution of water-bearing rock layer, water-bearing rock layer and water flow field by drilling, acoustic wave detection and isotope measurement, etc. According to the obtained data, the properties of the surrounding rock of the mine can be further measured, and the stable water storage space of surrounding rock characteristics should be selected as the open-air-based The mid-level storage area and low-level storage area of the semi-underground pumped storage power station in the pit;

C. Block the connection between each water storage area of the abandoned mine and its unstable space and goaf on the same plane; establish an adjustable channel between each water storage area and the upper water-bearing rock layer;

D. Arrange water storage tank, pump room and two-way generator set in the middle water storage area and the low water storage area respectively, and install the two-way generator set near the water storage in the middle water storage area and the low water storage area, using the original Pedestrian, power generation, and water transmission lines are divided between two or more depots.

E. The current generated by the new energy from the wind-solar complementary system is transmitted to the generator unit in the low-level water storage area through the cable arranged on the transmission line. The water source flows from the water storage space in the low-level water storage area (that is, the lower reservoir) into the low-level water tank. Under the action of the generator set, it is pumped out to the middle storage area through the water delivery channel, and then flows into the middle storage tank from the water storage space (ie, the middle reservoir) of the middle storage area, and is drawn out through the water transmission pipeline under the action of the middle bidirectional generator set To the open pit.

F. The water source flows into the middle reservoir and the lower reservoir from the open-pit mine through the two-way generator set through the water transmission channel to generate current, and the current is connected to the power grid through the cable;

Preferably, in the step A, the prediction of the range of the open pit caused by mining and the prediction of the water source are carried out by earth remote sensing technology. Among them, the prediction of the water source can be obtained through the calculation model of underground precipitation, surface water, groundwater and mine water underground relationship of the mining area and the movement law of coal mine mining groundwater. Furthermore, the distribution of aquifers, aquifers, and flow fields can be measured by drilling, acoustic detection, and isotope measurements to ensure that the location of the lower reservoir must be outside the area affected by the aquifer.

Preferably, in the step A, for the selection of the open pit, a calculation model can be specifically established through on-site analysis, and the distribution characteristics of the seepage field under the influence of mining can be determined by an isotope experiment method.

Preferably, in the step A, the reinforcement of the open pit may include at least the following methods: slope reinforcement and anti-seepage design, so as to ensure the safety of the upper reservoir formed by the open pit and stable water source volume. In addition, the following improvement methods can be adopted for the reinforcement of open pits: the stability of the rock layer can be adopted: shotcrete reinforcement, anti-slide piles, pressure grouting, concrete slope protection and shotcrete anti-seepage.

In addition, the design of the underground space and channel of the abandoned mine can also be implemented in the following specific preferred way: the inclined shaft can be drilled to the deep coal seam at the bottom of the open pit, and the open pit mining and the pit mining are carried out at the same time, that is, the open pit and the joint mining . Mainly inclined roadways. Inclined roadway is mainly divided into inclined shaft, dark inclined shaft, uphill and downhill. During the transformation, attention should be paid to blocking the connection between the abandoned mine water storage tunnel and the unstable space; for example, reinforced concrete is used to block the unstable tunnel and the water storage space to increase the stability of the mine, and ring shotcrete is used.

Preferably, the step B further includes determining the seepage flow under the influence of mining by the isotope experiment method for the rock layer characteristics, layer relationship, aquifer position, water content, aquifer water pressure size, aquifer thickness and water barrier characteristics Determination of field distribution characteristics, etc., to ensure that the location of the underground water storage area must be outside the area affected by the aquifer.

Preferably, the measurement of the surrounding rock properties of the mine in step B at least includes: rock hydraulic properties, rock failure characteristics under dynamic loading, and distribution of surrounding rock plastic zones.

Preferably, in the step B, the method for improving the properties of the rock layer (affecting the tightness and stability) may include at least the following aspects: For the tightness of the rock layer, a vertical anti-seepage combination may be adopted for the leakage reservoir section Horizontal anti-seepage cover. The anti-seepage scheme of the entire asphalt basin, the anti-seepage body and the basin form a whole, and the curtain grouting treatment of the foundation consolidation grouting machine is carried out. Preferably, in the process of measuring the geological parameters of the mine, the water storage volume of the middle reservoir and the lower reservoir is determined using the water storage space and the elevation of the water silo as standards.

Preferably, according to the height difference between the water storage areas, the stability characteristics of the water conveyance channel between the water storage areas are tested.

Preferably, according to the analysis of geological and rock mechanical properties, the water storage space of the abandoned mine shaft is subjected to anti-seepage maintenance or an anti-seepage layer is constructed.

Preferably, the connection between the lower water storage area and the goaf is established through the control valve. When the water-bearing rock layer enters the goaf under the influence of mining, the control valve is used to replenish the water source of the storage power station.

Preferably, taking advantage of the characteristics of the mine water self-flowing water tank in the mine design, the generator set is installed near the water tank of the middle reservoir and the lower reservoir respectively, and the original two or more parking yards are used to divide the pedestrian, power generation, and water transmission lines. .

Preferably, in the step E, a lower mine can be used to construct a lower reservoir. The lower reservoir cannot store water stably due to complex geological conditions, joint fissures and weak permeable rock layers in daily operation. Based on the obtained geological data of underground mining and the nature of the surrounding rock of the mine, a stable water storage space that cannot be penetrated by groundwater is selected as the lower reservoir of the open well combined abandoned mine pumped storage power station, and the water storage under the open well is blocked The connection between tunnel and unstable space. The semi-underground pumped storage power plant based on open pits will be further described with reference to FIGS. 2, 3 and 4. 2 is a schematic diagram of the space of a semi-underground pumped storage power plant based on an open pit according to an embodiment of the present disclosure; FIG. 3 is a median storage area and a low position of a semi-underground pumped storage power plant based on an open pit according to an embodiment of the present disclosure Plan layout diagram of water storage area, equipment layout and anti-blocking measures; FIG. 4 is a layout diagram section of a semi-underground pumped storage power plant based on an open pit according to an embodiment of the present disclosure.

Through the above steps A and B, the location of the high-level storage area, the middle-level storage area and the low-level storage area, as shown in Figures 2, 3, and 4, reinforces the open pit 18 at the surface 1 as the open pit The high-level water storage area of the semi-underground pumped storage power station, and through the distribution of the water-bearing rock layer 12 and the water-resistant rock layer 13 and other conditions, select stable mine roadways with stable surrounding rocks of different heights as semi-underground pumped storage based on open pits The underground water storage area of the power station, namely the middle water storage area 19 and the low water storage area 20. Abandoned mines generally include stable roadways, mined-out areas 17, shafts, unstable spaces, and recovery roadways 11, etc. What can be used as the underground water storage area of semi-underground pumped storage power stations based on open pits are not affected by mining and surrounding rocks Stable roadway with good conditions.

In addition, the upper reservoir of the pumped storage power station is a place for storing water and storing energy. The water volume of the upper and lower reservoirs must be recycled. The area is small, the storage capacity is small, and the water volume is limited. In addition to the small amount of leakage that needs to be considered in daily operation, the amount of water caused by evaporation of the upper reservoir needs to be considered. In this regard, the remote sensing technology can be used to measure and control the volume and evaporation of the water source in the open pit caused by mining, and determine the water supply time node to supply the water in time.

The underground water storage area includes water storage space (i.e., middle reservoir 8, lower reservoir 16), water storage tank (not shown), pump room (not shown), water pipeline well 5 connecting each water storage area and pedestrians and power transmission Well 6, middle bidirectional generator set 7a and low bidirectional generator set 7b. The water transmission pipeline well 5 is provided with a water transmission channel 15, the pedestrian and the power transmission well 6 can be used as a pedestrian channel, and a power transmission line 14 is paved. The water transmission pipeline well 5 and pedestrian and power transmission well 6 can be constructed on the basis of the original shaft of the abandoned mine, or can be re-excavated. Preferably, the guide tunnel can be excavated at an angle outside the affected area of the open pit, on the one hand, it is convenient for the installation of the lower unit, and on the other hand, it also serves as a ventilation pedestrian passage and a transmission line.

The middle bidirectional genset 7a and the low bidirectional genset 7b are bidirectional gensets, which can play the dual functions of pumping and power generation in the process of pumping and storing energy. The two-way generator set is arranged near the middle reservoir 8 and the lower reservoir 16, respectively. Under normal circumstances, in the original mine design, the mine roadway and cavern contain water and have the characteristics of self-inflow water tank. Therefore, in the process of pumping and storing energy, the bidirectional generator set only needs to suck out the water source through the water inlet in the water tank.

Each water storage area is also provided with a plugging wall 10 for blocking the connection between the water storage space and the unstable space and / or the goaf 17, etc. The plugging wall is provided with a control valve (not shown), It can ensure the controllable connection between the water storage space and the mined-out area, and when the mined-out area is affected by the mining, the water supply is guaranteed, and the water supply during the energy storage process is guaranteed. Preferably, the control valve may be a one-way valve, so that the water in the water storage area does not flow to the goaf area.

According to an embodiment of the present disclosure, the process of specifically implementing cascade pumped storage is as follows:

The current generated by wind energy 2 and solar energy 4 is transmitted to the low-level bidirectional generator set 7b through the transmission line 14 laid on the pedestrian and the transmission well 6, and the water source flows from the lower reservoir 16 into the water tank. Under the action of the low-level bidirectional generator set 7b, The water channel 15 is drawn out to the middle reservoir 8; under the action of the central bidirectional generator set 7a, the water source flows into the water reservoir from the middle reservoir 8 and then is further drawn out to the open pit through the water delivery channel 15.

The water flow uses the water channel 15 to flow from the open pit 18 to the middle reservoir 8 through the neutral bidirectional generator set 7a, and generates a current. The current is merged into the power grid 3 through the transmission line 14 laid on the pedestrian and the transmission well 6; the water flow further uses the water channel 15 From the middle reservoir 8 to the lower reservoir 16 through the low-level bidirectional generator set 7b, a current is generated, and the current is merged into the power grid 3 through the transmission line 14 laid on the pedestrian and the transmission well 6.

It should be noted that the high-level water storage area, the middle-level water storage area and the low-level water storage area described in the present disclosure are for the convenience of describing the relative height, and are not meant to be limited to three-layer water storage area. The number, depth and relative height difference of the water storage area can be set according to the actual conditions of the mine. For example: 2 to 3 layers of water storage areas are set in the middle storage area, 2 to 3 layers of water storage areas are set in the low storage area, and the water transfer between each storage area or between each storage area is based on actual operating conditions A two-way generator set is set near the water channel to realize cascade pumped storage.

In addition, it should also be understood that the bidirectional generator set of the present disclosure can play the dual functions of pumping and power generation during pumped storage. That is, by using the two-way generator set, the present disclosure only needs one water delivery channel to realize pumping and energy storage, without the need to provide two channels (such as an upward channel and a downward channel) for water pumping and drainage. The installation position of the two-way generator set should consider its own highest head. The “two-way generator set is set between the high water storage area and the middle water storage area, and between the middle water storage area and the low water storage area. "Interval" means: two-way generators can be installed in the high water storage area, the middle water storage area, and the low water storage area, or the two-way generators can be installed in the high water storage area and the middle water storage area respectively The area between the middle water storage area and the low water storage area is set on or near the water conveyance channel between the water storage areas.

In addition, for the location of the semi-underground pumped storage power station based on open pits proposed in this disclosure, reference can be made to at least one of the following preferred standards: (1) Lower coal seam floor, no water conducting structure and bad geology Conditions, low permeability of coal seam floor rock layer, stable mine water replenishment, easy to transfer water. (2) The cover rock in the mined-out area contains a fissure zone caused by mining, has strong conductivity, poor sealing and stability, and is generally not suitable as a storage reservoir, and should be isolated from the storage reservoir. (3) There is no resettlement task, the amount of ground attachments is small and the types are few, and the problem of relocation is easy to solve. (4) The reservoir site is far away from the urban water source, and does not pollute the urban water source. (5) The storage site is close to the urban sewage treatment plant.

The present disclosure improves the stability and reliability of pumped storage by constructing a semi-underground pumped storage power station based on open pits with stepped height differences, and at the same time solves the problem of large generator set installation restrictions. In addition, by making full use of open pits and underground abandoned areas for the layout of reservoirs and units, it can effectively expand the range of energy storage selection points, promote the safe and stable operation of the power grid, save costs, and promote the restoration of the natural ecological environment of the mining area. Environmental and social benefits.

It should be noted by those skilled in the art that the embodiments described in this disclosure are merely exemplary, and various other substitutions, changes, and improvements can be made within the scope of this disclosure. Therefore, the present disclosure is not limited to the above-mentioned embodiment, but is only limited by the claims.

Claims

A semi-underground pumped storage power station based on open pits is characterized by:

The semi-underground pumped storage power station based on open pits includes a high-level water storage area, a low-level water storage area, a water delivery channel and a bidirectional generator set;

The water conveyance channel is connected between the high water storage area and the low water storage area;

The two-way generator set is arranged between a high-level water storage area and a low-level water storage area, and the two-way generator set is used to pump water to store energy or generate electricity through the water transmission channel;

The high-level water storage area is an open pit of the abandoned mine, the low-level water storage area is an underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.
The semi-underground pumped storage power plant based on open pits according to claim 1, characterized in that:

The underground space of the abandoned mine shaft includes a roadway, a goaf area and a shaft, an underground water storage area is built in the roadway, and a water delivery channel is built in the shaft.
The semi-underground pumped storage power plant based on open pits according to claim 1, characterized in that:

At least one side of each underground water storage area is provided with a blocking wall, and the blocking wall is provided with a control valve.
The semi-underground pumped storage power plant based on open pits according to any one of claims 1 to 3, characterized in that:

The height difference between the high-level water storage area and the low-level water storage area is less than the highest lift of the bidirectional generator set.
The semi-underground pumped storage power plant based on open pits as claimed in claim 4, characterized in that:

The height difference between the high-level water storage area and the low-level water storage area is 200-400 m.
The semi-underground pumped storage power plant based on open pits according to any one of claims 1 to 3, characterized in that:

The semi-underground pumped storage power plant based on open pits also includes solar power generation devices and wind energy power generation devices;

The solar power generation device, the wind power generation device, and a semi-underground pumped storage power station based on an open pit form a wind-solar power generation complementary system.
The semi-underground pumped storage power plant based on open pits according to any one of claims 1 to 3, characterized in that:

The semi-underground pumped storage power station based on open pits also includes solar power generation devices;

The solar power generation device and a semi-underground pumped storage power station based on an open pit form a complementary power generation system.
The semi-underground pumped storage power plant based on open pits according to any one of claims 1 to 3, characterized in that:

The semi-underground pumped-storage power station based on open pits also includes a wind energy generating device;

The wind power generation device and the semi-underground pumped storage power station based on open pits form a complementary power generation system.
The fully underground pumped storage power station according to any one of claims 1 to 3, characterized in that:

The semi-underground pumped storage power station based on open pits also includes a central water storage area;

The middle water storage area is located between the high water storage area and the low water storage area, and the water conveyance channel is connected between the high water storage area and the middle water storage area, and the middle water storage area and the low water storage area Between the water storage areas, the two-way generator set is arranged between the high water storage area and the middle water storage area, and between the middle water storage area and the low water storage area;

The middle water storage area and the low water storage area are the underground water storage area, and the underground water storage area is located in the underground space of the abandoned mine.
A method for forming a semi-underground pumped storage power station based on open pits according to any one of claims 1-9, characterized in that:

The formation method of the semi-underground pumped storage power station based on open pit includes the following steps:

Open pits that reinforce abandoned mine shafts are used as high-level water storage areas;

Determine the properties of surrounding rocks, select abandoned mine roadways with stable surrounding rock characteristics to construct underground water storage areas, and construct at least low water storage areas with height differences as underground water storage areas;

Construct a water conveyance channel connecting the high water storage area and the low water storage area in the abandoned mine shaft, and set up a bidirectional generator set between the high water storage area and the low water storage area;

The two-way generator set is used to raise or drain water between the high-level water storage area and the low-level water storage area through the water conveyance channel for pumping and energy storage.
The method for forming a fully underground pumped storage power plant according to claim 10, characterized in that:

The formation method of the semi-underground pumped storage power station based on open pits also includes the following steps:

Construct a middle water storage area between the high water storage area and the low water storage area;

Construct a water delivery channel in the abandoned mine shaft that connects the high water storage area and the middle water storage area, and the middle water storage area and the low water storage area, and between the high water storage area and the middle water storage area, and Two-way generators are set between the middle water storage area and the low water storage area respectively;

The two-way generator set is used to carry out cascade pumping and storage by stepping pumping or drainage between the high water storage area and the middle water storage area, and the middle water storage area and the low water storage area through the water transmission channel.
The method for forming a semi-underground pumped storage power station based on an open pit according to claim 10, characterized in that:

The mined-out area of the abandoned mine shaft is a reserve water storage area.