Mine cooling system with vacuum ice slurry

Abstract

The application discloses a mine cooling system of vacuum ice slurry, which comprises a ground cooling water unit, a vacuum ice maker, a circulating water tank and a separation cylinder; a pressure exchange device and an air cooler arranged in the mine; the cooling water unit is used for precooling the cooling water for ice making; the circulating water tank and the vacuum ice maker are communicated with the output end of the cooling water unit; the vacuum ice maker is used for preparing ice slurry mixture from the pre-cooled cooling water; the output end of the vacuum ice maker is communicated with the separation cylinder; the separation cylinder is used for separating the ice slurry mixture into ice and water; the separated ice is transported into the circulating water tank to form ice-water mixture with the cooling water; the output end of the circulating water tank is communicated with the pressure exchange device; the pressure exchange device is communicated with the air cooler; the ice-water mixture supplied by the circulating water tank and the backwater of the air cooler realize pressure exchange through the pressure exchange device; the backwater of the air cooler after the pressure exchange enters the cooling water unit to form a cycle. The application has the advantages of high efficiency, energy saving and good heat exchange effect.

Description

Technical Field

[0001] This invention relates to the field of cooling technology for mines or tunnels, and more particularly to a mine cooling system using vacuum ice-making slurry. Background Technology

[0002] As coal mining depths increase and mining distances extend, more and more mines are experiencing high-temperature heat hazards. For example, metal mines are generally mined at depths exceeding 1,000 meters, with some reaching 2,000 meters, where the temperature of the surrounding rock underground can reach as high as 60°C. Therefore, mine cooling systems are essential. Currently, mine cooling systems are classified into three main categories based on the medium used: cold air cooling, cold water cooling, and ice cooling systems.

[0003] The cold air refrigeration system is suitable for cooling the working face nearby, within a distance of no more than 50 meters.

[0004] Chilled water refrigeration systems are currently the most common method. Chilled water generated by refrigeration units placed on the ground or underground is piped to the working face, where it is then cooled and dehumidified by an air cooler. The returned water then returns to the refrigeration unit for further cooling. However, as the distance between coal mining faces increases and the chilled water pipelines extend, significant cooling loss occurs along the way. The temperature rise of the chilled water reaching the working face is substantial, resulting in poor heat exchange at the end of the working face and failing to meet cooling requirements. Using ice-making methods can effectively ensure the temperature and heat exchange effect at the end of the working face. Currently, ice-making methods include low-temperature scraping ice or flake ice, and vacuum ice making.

[0005] Low-temperature flake ice making uses a compression evaporation refrigeration method. A freezer generates low temperatures inside an ice bucket, causing water to freeze on the inner wall of the bucket. Then, a rotating ice scraper breaks the water into ice shavings. This ice is solid and has relatively large particles. Low-temperature ice making is inefficient and energy-intensive, resulting in a low energy efficiency ratio (EER) of only 1-2.

[0006] Vacuum ice making operates on a completely different principle. It utilizes the fact that water boils at lower pressures. A near-vacuum is created within the tank using a turbo compressor. The evaporation of some water absorbs heat, causing the remaining water to crystallize. The ice crystals are no larger than 1mm and are still transported as a fluid. The main energy-consuming components of a vacuum ice making system are the compressor and the delivery pump. Its energy efficiency ratio (EER) can reach 8-9, far exceeding that of ordinary water chillers.

[0007] The patents are titled "Mine Ice-Cold Radiative Cooling System" (application number: 200420002466.7) and "Mine Ice-Cold Cooling System" (application number: 200720087261.7). The cooling system includes ground-based ice-making equipment, ice-transporting facilities, an underground ice-melting pool connected to the ground-based ice-making equipment via the ice-transporting facilities, and a working-face heat-absorbing device connected to the underground ice-melting pool via a cold water pipeline. This patent primarily addresses the cooling of sheet ice. Its main drawbacks are high energy consumption for ice making, easy blockage of the ice-transporting pipelines, and the need for energy to discharge the melted water to the surface.

[0008] The patent, titled "Mine Cooling System and Method" (Application No.: 200810198172.9), includes an ice slurry preparation device, a high- and low-pressure heat exchanger, and a working face cooler. The ice slurry generated by the ice slurry preparation device is connected to the high-pressure side of the high- and low-pressure heat exchanger via an ice slurry delivery pipe and a return water pipe. A high-pressure ice slurry delivery pump is installed on the ice slurry delivery pipe. The working face cooler is connected to the low-pressure side of the high- and low-pressure heat exchanger via a low-pressure cooling water pipe to form an underground cooling cycle. An underground cooling water pump is also installed on this cooling pipeline. The system cools the mine by utilizing the fluidity and large latent heat of the flowing ice slurry. The main problems are: the high- and low-pressure heat exchanger uses relatively small-diameter heat exchanger tubes, making them prone to clogging; furthermore, the ice slurry exchanges heat with cold water on the low-pressure side of the heat exchanger, leaving the low-pressure side still containing cold water, thus failing to solve the temperature rise problem during long-distance cooling.

[0009] The patents titled "Mine Vacuum Ice-Making Cooling System" (application number: 201110041664.9) and "Mine Vacuum Ice-Making Cooling System" (application number: 201120043111.2) both involve setting up cooling towers, chillers, water pumps, and vacuum ice makers on the surface. The chillers pre-cool the ice, and the vacuum ice maker produces ice crystal particles. However, the ice crystal particles are then transported underground to a melting pool to melt them into 5°C cold water, which is then sent to an air cooler at the working face to produce 12-18°C cold air, which is then delivered to the work site for cooling. The biggest problem with this system is the blockage in the pipeline during the ice crystal particle transport process underground, which prevents the system from operating normally. Furthermore, the melted water still needs to be drained back to the surface.

[0010] Therefore, there is an urgent need to provide a mine cooling system using vacuum ice-making slurry to solve the problems existing in the above-mentioned technologies. Summary of the Invention

[0011] The purpose of this invention is to provide a mine cooling system using vacuum ice-making slurry to solve the problems existing in the prior art.

[0012] To achieve the above objectives, the present invention provides a mine cooling system for vacuum ice-making slurry, including a chiller unit installed on the ground, a vacuum ice maker, a circulating water tank and a separator.

[0013] The chiller unit is used to pre-cool the water for ice making. The circulating water tank and the vacuum ice maker are both connected to the output end of the chiller unit. The vacuum ice maker is used to extract an ice slurry mixture from the pre-cooled water. The output end of the vacuum ice maker is connected to the separation cylinder. The separation cylinder is used to separate the ice slurry mixture into ice and water. The separated ice is transported to the circulating water tank and mixed with the cold water in the circulating water tank to form an ice-water mixture.

[0014] It also includes pressure exchange devices and air coolers installed underground;

[0015] The output end of the circulating water tank is connected to the pressure exchange device, which is connected to the air cooler. The ice-water mixture supplied by the circulating water tank and the return water of the air cooler exchange pressure through the pressure exchange device. After the pressure exchange, the return water of the air cooler enters the chiller unit for refrigeration, forming a cycle.

[0016] Preferably, it also includes a cooling tower installed on the ground, the cooling tower being connected to the chiller unit, the cooling tower being used to dissipate heat from the cooling water returning to the chiller unit; a water pump is installed on the pipeline at the output end of the cooling tower.

[0017] Preferably, the ice particles in the ice slurry mixture are less than 1 mm in size.

[0018] Preferably, the temperature of the chilled water after precooling by the chiller unit does not exceed 5°C.

[0019] Preferably, the circulating water tank and the pressure exchange device are connected via an ice slurry pump and an insulated pipeline.

[0020] Preferably, the water separated by the separator is pumped into the vacuum ice maker by a water pump.

[0021] Preferably, a downhole secondary low-pressure circuit is provided between the pressure exchange device and the air cooler, and the depressurized ice-water mixture enters the air cooler through the downhole secondary low-pressure circuit; the output end of the air cooler is connected to a return water pipeline, a water pump is installed on the return water pipeline, and the end of the return water pipeline is connected to the pressure exchange device.

[0022] Preferably, the flow area of ​​the pressure exchange device is not less than 300 cm². 2 .

[0023] Compared with the prior art, the present invention has the following advantages and technical effects:

[0024] 1. Employs vacuum ice-making technology, which is highly efficient and energy-saving;

[0025] 2. The ratio of ice to water mixture can be precisely controlled, and it can be transported through pipelines;

[0026] 3. The pressure exchange device uses pressure exchange, and the medium continues to be transported to the working face along the pipeline after the pressure is reduced. The pipeline along the way underground is still a mixture of ice and water; it can ensure that the water temperature is controlled within 0.5℃ within 5 kilometers of transportation.

[0027] 5. Make full use of the latent heat of melting ice to compensate for pipeline losses along the way, and ensure the cold water temperature and heat exchange effect at the end.

[0028] 6. The water from the melting ice does not need to be discharged; it is returned to the ground for reuse after pressure exchange, thus saving energy and water.

[0029] 7. By using a pressure exchange device, the high-pressure potential energy of cold water is converted into the potential energy of low-pressure hot water, thereby overcoming the well depth. The pump head only needs to consider the pipeline resistance and does not need to consider the height difference. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a system flow diagram of the mine cooling system using vacuum ice-making slurry of the present invention;

[0032] Figure 2 This is a flow chart of the pressure exchange device of the present invention;

[0033] In the diagram: 1. Chiller unit; 2. Vacuum ice maker; 3. Circulating water tank; 4. Separator; 5. Pressure exchange device; 6. Air cooler; 7. Cooling tower; 8. Water pump; 9. Ice slurry pump; 10. Insulated pipeline; 11. Downhole secondary low-pressure circuit; 12. Return water pipeline. Detailed Implementation

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. The described embodiments are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] like Figure 1As shown, the present invention provides a mine cooling system for vacuum ice-making slurry, including a chiller unit 1, a vacuum ice maker 2, a circulating water tank 3, and a separator 4 installed on the ground;

[0036] Chiller unit 1 is used to precool the chilled water for ice making. Circulating water tank 3 and vacuum ice maker 2 are both connected to the output of chiller unit 1. Vacuum ice maker 2 is used to extract ice slurry mixture from the precooled chilled water. The output of vacuum ice maker 2 is connected to separation cylinder 4. Separation cylinder 4 is used to separate the ice slurry mixture into ice and water. The separated ice is transported to circulating water tank 3 and mixed with the chilled water in circulating water tank 3 to form an ice-water mixture.

[0037] It also includes a pressure exchange device 5 and an air cooler 6 installed underground;

[0038] The output end of the circulating water tank 3 is connected to the pressure exchange device 5, and the pressure exchange device 5 is connected to the air cooler 6. The ice-water mixture supplied by the circulating water tank 3 and the return water of the air cooler 6 exchange pressure through the pressure exchange device 5. After the pressure exchange, the return water of the air cooler 6 enters the chiller unit 1 for refrigeration, forming a cycle.

[0039] Furthermore, in order to improve the mixing effect of ice and water, a stirring device is installed in the circulating water tank 3.

[0040] Furthermore, it also includes a cooling tower 7 installed on the ground, which is connected to the chiller unit 1. The cooling tower 7 is used to dissipate heat from the cooling water that flows back to the chiller unit 1; a water pump 8 is installed on the pipeline at the output end of the cooling tower 7.

[0041] Furthermore, the ice particles in the ice slurry mixture are less than 1 mm in size.

[0042] Furthermore, the temperature of the chilled water after precooling by chiller unit 1 does not exceed 5°C.

[0043] Furthermore, the circulating water tank 3 and the pressure exchange device 5 are connected via the ice slurry pump 9 and the insulated pipeline 10.

[0044] Furthermore, the water separated by the separator 4 is pumped to the vacuum ice maker 2 by the water pump 8.

[0045] Furthermore, a downhole secondary low-pressure circuit 11 is provided between the pressure exchange device 5 and the air cooler 6. The depressurized ice-water mixture enters the air cooler 6 through the downhole secondary low-pressure circuit 11. The output end of the air cooler 6 is connected to a return water pipe 12, and a water pump 8 is installed on the return water pipe 12. The end of the return water pipe 12 is connected to the pressure exchange device 5.

[0046] Furthermore, the flow area of ​​the pressure exchange device 5 is not less than 300 cm². 2 To avoid causing ice blockage.

[0047] Furthermore, such as Figure 2 As shown, the pressure exchange device 5 includes three chamber pipes, which are respectively connected to the inlet and outlet of cold water and the inlet and outlet of hot water return. Valves are installed between the three chamber pipes and the main pipe to control their on / off states. The specific operating steps are as follows:

[0048] Step 1: In chamber A, valve 1301 is open, allowing high-pressure cold water to enter; valve 1311 is open, allowing high-pressure warm water to exit.

[0049] Driven by a single circulation loop, high-pressure cold water delivers high-pressure warm water from chamber A to the ground cooling system;

[0050] When valve 1314 in chamber B is open, low-pressure warm water enters; when valve 1304 is open, low-pressure cold water exits. Driven by the secondary circuit circulation pump, low-pressure warm water is injected into chamber B, thereby sending the cold water in chamber B to the secondary circuit.

[0051] All valves in chamber C are closed, and the chamber is filled with high-pressure warm water. It will be filled after the pressure is balanced.

[0052] Step 2: Close all valves in chamber A:

[0053] A is filled with high-pressure cold water and will be filled after pressure compensation.

[0054] Valve 1303 (high-pressure cold water) and valve 1313 (high-pressure warm water) in chamber B are open;

[0055] Through a single loop, the high-pressure warm water in chamber B is pushed by high-pressure cold water into the ground cooling system for circulation.

[0056] When chamber C valve 1316 is open, low-pressure warm water enters; when valve 1306 is open, low-pressure cold water exits.

[0057] Through the circulation of the secondary circuit, low-pressure warm water is injected into chamber C, thereby sending the cold water in chamber C into the secondary circuit;

[0058] Step 3: Open valve 1312 in chamber A to allow low-pressure warm water to enter; open valve 1302 to allow low-pressure cold water to exit.

[0059] Through the circulation of the secondary circuit, low-pressure warm water is injected into chamber A, thereby sending the cold water in chamber A into the secondary circuit.

[0060] All valves in chamber B are closed, and the chamber is filled with high-pressure cold water. After pressure compensation, the chamber is filled.

[0061] Through a single loop, the high-pressure warm water in chamber C is pushed by high-pressure cold water into the ground cooling system for circulation.

[0062] In this way, a cycle is formed by the continuous switching of the three cavity tubes.

[0063] The mine cooling system for vacuum ice-making slurry provided by this invention operates as follows: Cold water is pre-cooled to 5°C by a chiller unit 1. Most of the cold water is sent to a circulating water tank 3, and a portion is sent to a vacuum ice maker 2. The vacuum ice maker 2 produces an ice slurry mixture, which is then sent to a separation cylinder 4. The separation cylinder 4 removes the upper ice and sends it back to the circulating water tank 3 via a belt conveyor. The lower cold water is then pumped back to the vacuum ice maker 2 by a water pump 8 for further ice production. Through the separation cylinder 4, the mixing ratio of ice slurry and cold water can be precisely controlled. The ice particles in the ice-water mixture are less than 1mm in size and can be directly transported as a fluid. The ice-water mixture in the circulating water tank 3 is transported to a pressure exchange device 5 underground via an ice slurry pump 9 and an insulated pipeline 10. The pressure exchange device 5 performs pressure exchange through direct contact between hot and cold water, reducing the pressure of the ice slurry mixture from high pressure to low pressure while simultaneously raising the pressure of the hot water returning from the working face from low pressure to high pressure, thus achieving pressure exchange. After depressurization, the ice-water mixture enters the underground secondary low-pressure circuit 11, is transported to the working face through the pipeline, enters the air cooler 6 for heat exchange, and the hot water after heat exchange returns to the pressure exchange device 5 through the return water pipeline 12. After being pressurized, it overcomes the well depth and returns to the surface, and enters the chiller unit 1 for circulating cooling.

[0064] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A mine cooling system using vacuum ice-making slurry, characterized in that, Includes a ground-mounted chiller unit (1), a vacuum ice maker (2), a circulating water tank (3), and a separator (4); The chiller unit (1) is used to pre-cool the chilled water for ice making. The circulating water tank (3) and the vacuum ice maker (2) are both connected to the output end of the chiller unit (1). The vacuum ice maker (2) is used to extract ice slurry mixture from the pre-cooled chilled water. The output end of the vacuum ice maker (2) is connected to the separation cylinder (4). The separation cylinder (4) is used to separate the ice slurry mixture into ice and water. The separated ice is transported to the circulating water tank (3) and mixed with the chilled water in the circulating water tank (3) to form an ice-water mixture. It also includes a pressure exchange device (5) and an air cooler (6) installed downhole. The output end of the circulating water tank (3) is connected to the pressure exchange device (5), and the pressure exchange device (5) is connected to the air cooler (6). The ice-water mixture supplied by the circulating water tank (3) and the return water of the air cooler (6) exchange pressure through the pressure exchange device (5). After the pressure exchange, the return water of the air cooler (6) enters the chiller unit (1) for cooling, forming a cycle. The pressure exchange device (5) includes three chamber pipes, which are respectively connected to the inlet and outlet of cold water and the inlet and outlet of hot water return. Valves are installed between the three chamber pipes and the main pipe to control their opening and closing. The pressure exchange device (5) performs pressure exchange through direct contact between cold and hot water. A downhole secondary low-pressure circuit (11) is provided between the pressure exchange device (5) and the air cooler (6). The depressurized ice-water mixture enters the air cooler (6) through the downhole secondary low-pressure circuit (11). The output end of the air cooler (6) is connected to a return water pipeline (12). A water pump (8) is installed on the return water pipeline (12). The end of the return water pipeline (12) is connected to the pressure exchange device (5).

2. The mine cooling system using vacuum ice-making slurry according to claim 1, characterized in that, It also includes a cooling tower (7) installed on the ground, which is connected to the chiller unit (1). The cooling tower (7) is used to dissipate heat from the cooling water that flows back to the chiller unit (1). A water pump (8) is installed on the pipeline at the output end of the cooling tower (7).

3. The mine cooling system for vacuum ice-making slurry according to claim 1, characterized in that, The ice particles in the ice slurry mixture are less than 1 mm in size.

4. The mine cooling system for vacuum ice-making slurry according to claim 1, characterized in that, The temperature of the chilled water after precooling by the chiller unit (1) does not exceed 5°C.

5. The mine cooling system for vacuum ice-making slurry according to claim 1, characterized in that, The circulating water tank (3) and the pressure exchange device (5) are connected by an ice slurry pump (9) and an insulated pipeline (10).

6. The mine cooling system for vacuum ice-making slurry according to claim 1, characterized in that, The water separated by the separator (4) is pumped to the vacuum ice maker (2) by the water pump (8).

7. The mine cooling system for vacuum ice-making slurry according to claim 1, characterized in that, The flow area of ​​the pressure exchange device (5) is not less than 300 cm². 2 .

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