Well washing system and well washing method for in-situ leaching uranium mining

Abstract

The invention provides a well washing system and a well washing method for in-situ leaching uranium mining, and relates to the field of in-situ leaching uranium mining well washing, the system comprises an air compressor system comprising a high-pressure air compressor set and a low-pressure air compressor set; the pipeline system is provided with an air path control structure and further comprises a first air inlet pipeline, a second air inlet pipeline, a third air inlet pipeline, a first air outlet pipeline and a second air outlet pipeline, and a high-pressure air bag is arranged between the first air inlet pipeline and the first air outlet pipeline. A low-pressure air bag is arranged between the second air inlet pipeline and the second air outlet pipeline, and a third pressure sensor is arranged at the bottom of the underground air pipe. The air compressor system, the air channel control structure, the first pressure sensor, the second pressure sensor and the third pressure sensor are electrically connected with the control system. According to the system, on the premise that the rated power of the air compressor is reduced, on one hand, the well washing efficiency is greatly improved, and on the other hand, energy consumption in the well washing process is effectively reduced.

Description

Technical Field

[0001] The invention relates to the field of well washing for in-situ leaching of uranium, and in particular to a well washing system and a well washing method for in-situ leaching of uranium. Background Art

[0002] In-situ leaching of uranium is the main mining process for natural uranium in my country. Due to the relatively loose strata of sandstone uranium deposits, the possibility of particle migration is relatively high, and chemical reactions lead to precipitation and other factors, underground blockage is relatively serious. Therefore, in-situ leaching of uranium requires a high frequency of well washing, a large number of superimposed process wells, and a large workload for well washing.

[0003] In the in-situ leaching uranium mining process at home and abroad, the most commonly used well washing method is air well washing, that is, using an air compressor to pressurize compressed air into the well, and the air and the underground fluid form a gas-water mixture and lift it to the ground, while generating negative pressure at the bottom of the well to clear the blockage.

[0004] However, the current in-situ uranium leaching industry generally uses multiple identical air compressors to form an air compressor unit, and intermittently washes the wells at a certain time. As the depth of the in-situ uranium leaching well increases, the well washing air volume and pressure increase, and the well washing time increases, resulting in a continuous increase in power consumption, but the well washing efficiency is limited. Therefore, there is an urgent need for a well washing system and well washing method for in-situ uranium leaching. On the premise of reducing the rated power of the air compressor, on the one hand, the well washing efficiency needs to be greatly improved, and on the other hand, the energy consumption during the well washing process needs to be effectively reduced. Summary of the invention

[0005] The purpose of the present invention is to provide a well washing system and a well washing method for in-situ leaching of uranium to improve the above problems. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present application provides a well washing system for in-situ leaching of uranium, the system comprising:

[0007] An air compressor system, the air compressor system comprising a high-pressure air compressor unit and a low-pressure air compressor unit, the high-pressure air compressor unit comprising at least one high-pressure air compressor, and the low-pressure air compressor unit comprising at least one low-pressure air compressor;

[0008] A pipeline system, wherein an air circuit control structure is arranged on the pipeline system, and the pipeline system further comprises a first air inlet pipeline, a second air inlet pipeline, a third air inlet pipeline, a first air outlet pipeline and a second air outlet pipeline, a high-pressure air bag is arranged between the first air inlet pipeline and the first air outlet pipeline, a first pressure sensor is arranged on the high-pressure air bag, a low-pressure air bag is arranged between the second air inlet pipeline and the second air outlet pipeline, a second pressure sensor is arranged on the low-pressure air bag, the first air outlet pipeline and the second air outlet pipeline are connected to the top of the underground air duct after being connected, and a third pressure sensor is arranged at the bottom of the underground air duct;

[0009] A control system, wherein the air compressor system, the air circuit control structure, the first pressure sensor, the second pressure sensor and the third pressure sensor are electrically connected to the control system.

[0010] Preferably, the gas circuit control structure includes a one-way valve group and a solenoid valve group, the one-way valve group includes a first one-way valve, a second one-way valve, a third one-way valve, a fourth one-way valve and a fifth one-way valve, and the solenoid valve group includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve and a fifth solenoid valve;

[0011] Wherein, the first one-way valve and the first solenoid valve are arranged on the first air intake pipeline, and a first connection position is arranged between the first solenoid valve and the high-pressure air bag;

[0012] The second one-way valve and the second solenoid valve are arranged on the second air intake pipeline, and a second connection point is arranged between the second one-way valve and the second solenoid valve;

[0013] One end of the third air intake pipeline is connected to the first connection position, and the other end of the third air intake pipeline is connected to the second connection position, and the third one-way valve and the third solenoid valve are arranged on the third air intake pipeline;

[0014] The fourth one-way valve and the fourth solenoid valve are arranged on the first air outlet pipeline, and the fifth one-way valve and the fifth solenoid valve are arranged on the second air outlet pipeline.

[0015] In a second aspect, the present application further provides a well washing method for in-situ leaching of uranium, the method comprising using the well washing system for in-situ leaching of uranium described above, comprising:

[0016] The underground air pipe is placed underground until the bottom of the underground air pipe is set at the level of the underground ore layer, and the third pressure sensor is used to collect the real-time underground pressure corresponding to the bottom of the underground air pipe;

[0017] Rapid gas storage stage: the control system controls the high-pressure air compressor unit and the low-pressure air compressor unit to start at the same time, and the second solenoid valve, the fifth one-way valve and the fifth solenoid valve in the gas circuit control structure are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state, and the air is delivered to the underground air duct through the high-pressure air bag;

[0018] First control state: when the pressure measured by the first pressure sensor reaches the rated pressure of the low-pressure air compressor unit, the control system controls the closing of the third one-way valve and the third solenoid valve in the air path control structure, and opens the second solenoid valve at the same time, so that the low-pressure air compressor unit inflates the low-pressure air bag;

[0019] Second control state: when the pressure measured by the second pressure sensor reaches the rated pressure of the low-pressure air bag, the control system controls the low-pressure air compressor unit to stop working, and in the air path control structure, the second one-way valve, the second solenoid valve, the third one-way valve, the third solenoid valve, the fifth one-way valve and the fifth solenoid valve are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state;

[0020] One-time well washing: when the real-time downhole pressure of the third pressure sensor is greater than the preset first blowout pressure value, the high-pressure air compressor unit continues to pressurize until the fluid in the well is sprayed to the ground; thereafter, when the real-time downhole pressure of the third pressure sensor is less than the pressure value of the second pressure sensor, the control system controls the second solenoid valve and the fifth solenoid valve to be in the open state, and the high-pressure air compressor unit and the low-pressure air compressor unit jointly supply air to the well to achieve one-time well washing in the well.

[0021] Preferably, after a well wash, intermittent well wash is performed according to the real-time downhole pressure of the third pressure sensor, the preset low value of the dynamic water level and the preset second blowdown pressure value, including:

[0022] When the real-time downhole pressure of the third pressure sensor is less than or equal to the low value of the dynamic water level, the control system controls the closing of the fourth solenoid valve and the fifth solenoid valve, controls the high-pressure air compressor unit to supply air to the high-pressure air bag to the rated pressure, and controls the low-pressure air compressor unit to supply air to the low-pressure air bag to the rated pressure;

[0023] When the water level in the well rises and the real-time downhole pressure of the third pressure sensor is greater than the second blowdown pressure value, the control system controls the low-pressure air compressor unit to work, and in the air circuit control structure, the second one-way valve, the second solenoid valve, the fifth one-way valve and the fifth solenoid valve are in the open state, and the remaining solenoid valves and the remaining one-way valves are in the closed state, so that the low-pressure air compressor unit continues to work and performs intermittent well washing in the well within the preset time corresponding to the preset low value of the dynamic water level.

[0024] Preferably, the well washing method for in-situ leaching of uranium comprises: before placing the downhole air duct underground, determining the rated pressure of the high-pressure air compressor unit, the rated pressure of the high-pressure air compressor unit being calculated as:

[0025] Obtain the absolute elevation of the static water level above the ore layer, the absolute elevation of the ore layer and the well washing resistance;

[0026] The absolute elevation of the static water level above the ore layer and the absolute elevation of the ore layer are solved by a preset hydrostatic pressure model to obtain the bottom hole hydrostatic pressure;

[0027] The bottom hole hydrostatic pressure and the well-washing resistance are solved by a preset high-pressure air compressor unit calculation model to obtain the rated pressure of the high-pressure air compressor unit.

[0028] Preferably, the well washing method for in-situ leaching of uranium comprises: before placing the downhole air duct underground, it also comprises: determining the rated pressure of the low-pressure air compressor unit, and the rated pressure of the low-pressure air compressor unit is calculated as:

[0029] Obtain the absolute elevation of the dynamic water level, the absolute elevation of the ore layer and the well washing resistance;

[0030] The absolute elevation of the dynamic water level and the absolute elevation of the ore layer are solved by a preset dynamic water pressure model to obtain the bottom hole dynamic water level pressure;

[0031] The bottom well dynamic water level pressure and the well washing resistance are solved by using a preset low-pressure air compressor unit calculation model to obtain the rated pressure of the low-pressure air compressor unit.

[0032] The beneficial effects of the present invention are:

[0033] The present invention determines the rated pressure of the high-pressure air compressor unit and the rated pressure of the low-pressure air compressor unit by calculation, thereby realizing high and low configuration of the air compressor unit, reducing the rated power of the air compressor and saving the investment in the air compressor; in addition, the present invention determines the operating time of the air compressor according to the real-time change of the dynamic water level with the help of bottom hole pressure sensor monitoring, greatly improving the well washing efficiency of in-situ leaching uranium and effectively reducing the energy consumption in the well washing process, such as power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 Schematic diagram of the structure of the well washing system described in an embodiment of the present invention;

[0036] Figure 2 It is a schematic diagram of the arrangement structure of the one-way valve group and the solenoid valve group described in the embodiment of the present invention;

[0037] Figure 3 H1, H2 ...3, H4, H5, H6, H7, H8, H9, H 31 and H 32 Schematic diagram of the location structure;

[0038] Markings in the figure:

[0039] 1. High-pressure air compressor unit; 2. Low-pressure air compressor unit; 3. High-pressure air bag; 4. Low-pressure air bag; 5. Control system; 6. Downhole air duct; 71. First one-way valve; 72. Second one-way valve; 73. Third one-way valve; 74. Fourth one-way valve; 75. Fifth one-way valve; 81. First solenoid valve; 82. Second solenoid valve; 83. Third solenoid valve; 84. Fourth solenoid valve; 85. Fifth solenoid valve; 100. First pressure sensor; 200. Second pressure sensor; 300. Third pressure sensor. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0041] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] Embodiment 1:

[0043] like Figure 1 and Figure 2 As shown, this embodiment provides a well washing system for in-situ leaching of uranium, the system comprising:

[0044] An air compressor system, the air compressor system comprising a high-pressure air compressor unit 1 and a low-pressure air compressor unit 2, the high-pressure air compressor unit 1 comprising at least one high-pressure air compressor, and the low-pressure air compressor unit 2 comprising at least one low-pressure air compressor;

[0045] A pipeline system, wherein an air circuit control structure is arranged on the pipeline system, and the pipeline system further comprises a first air inlet pipeline, a second air inlet pipeline, a third air inlet pipeline, a first air outlet pipeline and a second air outlet pipeline, a high-pressure air bag 3 is arranged between the first air inlet pipeline and the first air outlet pipeline, a first pressure sensor 100 is arranged on the high-pressure air bag 3, a low-pressure air bag 4 is arranged between the second air inlet pipeline and the second air outlet pipeline, a second pressure sensor 200 is arranged on the low-pressure air bag 4, the first air outlet pipeline and the second air outlet pipeline are connected to the top of the downhole air pipe 6, and a third pressure sensor 300 is arranged at the bottom of the downhole air pipe 6;

[0046] The control system 5 , the air compressor system, the air circuit control structure, the first pressure sensor 100 , the second pressure sensor 200 , and the third pressure sensor 300 are electrically connected to the control system 5 .

[0047] In the well washing system, the air volume generated by the high-pressure air compressor unit 1 is 25%-50% of the air volume generated by the low-pressure air compressor unit 2, wherein the air volume generated by the low-pressure air compressor unit 2 is determined by field tests in combination with the well diameter and permeability. Preferably, the air volume generated by the low-pressure air compressor unit 2 should be 4-6m 3 / min, the air volume of high-pressure air compressor unit 1 is 50% of the air volume of low-pressure air compressor unit 2, i.e. 2m 3 / min.

[0048] In the control system 5, it includes a circuit component, a touch screen controller, a serial port output circuit and a host computer, wherein the circuit component is electrically connected to the touch screen controller, the touch screen controller is electrically connected to the serial port output circuit, the host computer is electrically connected to the serial port output circuit, the circuit component is used to collect and process the analog pressure signal, the serial port output circuit and the host computer are used to generate control signals for the solenoid valve, the high-pressure air compressor unit 1 and the low-pressure air compressor unit 2.

[0049] In the well washing system, in order to clarify the specific setting of the gas circuit control structure: the gas circuit control structure includes a one-way valve group and a solenoid valve group, the one-way valve group includes a first one-way valve 71, a second one-way valve 72, a third one-way valve 73, a fourth one-way valve 74 and a fifth one-way valve 75, and the solenoid valve group includes a first solenoid valve 81, a second solenoid valve 82, a third solenoid valve 83, a fourth solenoid valve 84 and a fifth solenoid valve 85;

[0050] The first one-way valve 71 and the first solenoid valve 81 are arranged on the first air intake pipeline, and a first connection position is arranged between the first solenoid valve 81 and the high-pressure air bag 3;

[0051] The second one-way valve 72 and the second solenoid valve 82 are arranged on the second air intake pipeline, and a second connection position is arranged between the second one-way valve 72 and the second solenoid valve 82;

[0052] One end of the third air intake pipeline is connected to the first connection position, and the other end of the third air intake pipeline is connected to the second connection position. The third one-way valve 73 and the third solenoid valve 83 are arranged on the third air intake pipeline.

[0053] The fourth one-way valve 74 and the fourth solenoid valve 84 are arranged on the first air outlet pipeline, and the fifth one-way valve 75 and the fifth solenoid valve 85 are arranged on the second air outlet pipeline.

[0054] Embodiment 2:

[0055] This embodiment provides a well washing method for in situ leaching of uranium, using a well washing system for in situ leaching of uranium as described above. The method includes steps S1 to S5, specifically:

[0056] S1: placing the underground air pipe 6 underground until the bottom of the underground air pipe 6 is set at the horizontal position of the underground ore layer, and the third pressure sensor 300 is used to collect the real-time underground pressure corresponding to the bottom of the underground air pipe 6;

[0057] S2: Rapid gas storage stage: the control system 5 controls the high-pressure air compressor unit 1 and the low-pressure air compressor unit 2 to start at the same time, and the second solenoid valve 82, the fifth one-way valve 75 and the fifth solenoid valve 85 in the gas circuit control structure are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state, and the air is delivered to the underground air pipe 6 through the high-pressure air bag 3;

[0058] For the high-pressure air compressor unit 1, its rated air volume is low, while for the low-pressure air compressor unit 2, its rated air volume is high. In step S2, the high-pressure air compressor unit 1 and the low-pressure air compressor unit 2 are turned on at the same time to realize rapid gas storage in the high-pressure air bag 3 and underground, and the gas storage efficiency is high.

[0059] S3: First control state: When the pressure measured by the first pressure sensor 100 reaches the rated pressure of the low-pressure air compressor unit 2, the control system 5 controls the closing of the third one-way valve 73 and the third solenoid valve 83 in the air path control structure, and opens the second solenoid valve 82 at the same time, so that the low-pressure air compressor unit 2 inflates the low-pressure air bag 4;

[0060] S4: second control state: when the pressure measured by the second pressure sensor 200 reaches the rated pressure of the low-pressure air bag 4, the control system 5 controls the low-pressure air compressor unit 2 to stop working, and the second one-way valve 72, the second solenoid valve 82, the third one-way valve 73, the third solenoid valve 83, the fifth one-way valve 75 and the fifth solenoid valve 85 in the air path control structure are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state;

[0061] S5: One well flushing: When the real-time downhole pressure of the third pressure sensor 300 is greater than the preset first blowdown pressure value, the high-pressure air compressor unit 1 continues to pressurize until the fluid in the well is sprayed to the ground; thereafter, when the real-time downhole pressure of the third pressure sensor 300 is less than the pressure value of the second pressure sensor 200, the control system 5 controls the second solenoid valve 82 and the fifth solenoid valve 85 to be in the open state, and the high-pressure air compressor unit 1 and the low-pressure air compressor unit 2 jointly supply air to the well to achieve one well flushing in the well.

[0062] In step S5, the first blowdown pressure value corresponds to the bottom well hydrostatic pressure P 静 When the high pressure air compressor unit 1 continues to pressurize more than P 静 , until the fluid in the well is sprayed to the ground, completing a well wash.

[0063] After step S5, intermittent well washing is performed according to the real-time downhole pressure of the third pressure sensor 300, the preset low dynamic water level value and the preset second blowdown pressure value, including S6 and S7, specifically:

[0064] S6: When the real-time downhole pressure of the third pressure sensor 300 is less than or equal to the low value H of the dynamic water level 32 When the control system 5 controls the closing of the fourth solenoid valve 84 and the fifth solenoid valve 85, controls the high-pressure air compressor unit 1 to supply air to the high-pressure air bag 3 to the rated pressure, and controls the low-pressure air compressor unit 2 to supply air to the low-pressure air bag 4 to the rated pressure;

[0065] S7: When the water level in the well rises and the real-time downhole pressure of the third pressure sensor 300 is greater than the second blowdown pressure value, the control system 5 controls the low-pressure air compressor unit 2 to work, and in the air circuit control structure, the second one-way valve 72, the second solenoid valve 82, the fifth one-way valve 75 and the fifth solenoid valve 85 are in the open state, and the remaining solenoid valves and the remaining one-way valves are in the closed state, so that the low-pressure air compressor unit 2 continues to work and performs intermittent well washing in the well within the preset time corresponding to the preset low value of the dynamic water level.

[0066] like Figure 3 As shown, the second spray pressure value is H 31 The corresponding pressure value, where H31 is the high value of dynamic water level, H 32 is the low value of the dynamic water level, H1 is the absolute elevation of the static water level above the ore layer, and H2 is the absolute elevation of the ore layer.

[0067] Embodiment 3:

[0068] This embodiment provides a well washing method for in-situ leaching of uranium, using a well washing system for in-situ leaching of uranium as described above, before placing the downhole air duct 6 underground, including: determining the rated pressure of the high-pressure air compressor unit 1, the rated pressure calculation of the high-pressure air compressor unit 1 includes steps S21 to S23, specifically:

[0069] S21: Obtaining the absolute elevation of the static water level above the ore layer, the absolute elevation of the ore layer, and the well washing resistance;

[0070] In step S21, in obtaining the well-washing resistance, the well-washing resistance is calculated as:

[0071]

[0072] In the above formula (1), △P 阻 represents the well washing resistance, in MPa; λ represents the friction resistance coefficient; V represents the average flow velocity in the underground air duct, in m / s; ρ 空 Indicates air density in kg / m 3 ; L is the length of the underground air duct, in m; D is the inner diameter of the underground air duct, in m.

[0073] S22: solving the absolute elevation of the static water level above the ore layer and the absolute elevation of the ore layer by using a preset hydrostatic pressure model to obtain the bottom hole hydrostatic pressure;

[0074] In step S22, the hydrostatic pressure model is:

[0075]

[0076] In the above formula (2), P 静 Represents the bottom water pressure in MPa; ρ 水 Indicates the density of water in kg / m 3 ; g is the acceleration due to gravity, in m / s 2 ; H1 is the absolute elevation of the static water level above the ore layer, in m; H2 is the absolute elevation of the ore layer, in m.

[0077] S23: Solving the bottom hole hydrostatic pressure and the well washing resistance by using a preset high-pressure air compressor unit calculation model to obtain the rated pressure of the high-pressure air compressor unit 1.

[0078] In step S23, the high-pressure air compressor unit calculation model is:

[0079] P 10 =P 静 +△P 阻 +K1……………………(3)

[0080] In the above formula (3), P 10 Indicates the rated pressure of high-pressure air compressor unit 1, P 静 Indicates the bottom water pressure, △P 阻 It represents the well washing resistance, K1 represents the first excess starting pressure, and its value range is 0.2-1.0. The units of the above parameters are all MPa.

[0081] Embodiment 4:

[0082] This embodiment provides a well washing method for in-situ leaching of uranium, using a well washing system for in-situ leaching of uranium as described above, before placing the downhole air duct 6 underground, including: determining the rated pressure of the low-pressure air compressor unit 2, the rated pressure calculation of the low-pressure air compressor unit 2 includes steps S31 to S33, specifically:

[0083] S31: Obtaining the absolute elevation of the dynamic water level, the absolute elevation of the ore layer, and the well washing resistance;

[0084] The calculation principle of the well-washing resistance in step S31 is the same as the calculation principle of the well-washing resistance in step S21.

[0085] S32: solving the absolute elevation of the dynamic water level and the absolute elevation of the ore layer through a preset dynamic water pressure model to obtain the bottom hole dynamic water level pressure;

[0086] In step S32, the hydrodynamic pressure model is:

[0087]

[0088] In the above formula (4), P 动 Indicates the dynamic water level pressure at the bottom of the well, in MPa; ρ 水 Indicates the density of water in kg / m 3 ; g is the acceleration due to gravity, in m / s 2 ;H 31 is the dynamic water level height, in m; H2 is the absolute elevation of the ore layer, in m;

[0089] S33: Solving the bottom hole dynamic water level pressure and the well washing resistance through a preset low-pressure air compressor unit calculation model to obtain the rated pressure of the low-pressure air compressor unit 2.

[0090] In step S33, the calculation model of the low-pressure air compressor unit is:

[0091] P 20 =P 动 +△P 阻 +K2……………………(5)

[0092] In the above formula (5), P 20 Indicates the rated pressure of low-pressure air compressor unit 2, P 动 Indicates the dynamic water level pressure at the bottom of the well, △P 阻 represents the well washing resistance, K2 represents the second excess starting pressure, and its value range is 0.1-0.5. The units of the above parameters are all MPa.

[0093] Embodiment 5:

[0094] The depth of a uranium deposit is 500-550m, the ore layer is located at 520-530mm, the absolute elevation of the static water level is 100-150m, the well diameter is 128mm or 80mm, and the permeability is about 0.2m / d;

[0095] By the calculation formula in Example 2, it is calculated that:

[0096] The bottom water pressure is between 3.7-4.3MPa, the well washing resistance is 0.3MPa, the first excess starting pressure has a value range of 0.2-1.0, and the high-pressure air compressor uses an air compressor with a rated pressure of 5.0MPa.

[0097] Through field tests, the dynamic water level during well washing is 250-350m. Combined with the well depth and ore layer location, the low-value water pressure of the dynamic water level is calculated to be 2.2-2.5MPa, the well washing resistance is 0.3MPa, the second excess starting pressure value is 0.2-0.3MPa, and the low-pressure air compressor uses an air compressor with a rated pressure of 3.0MPa.

[0098] Therefore, according to the above parameters, the air compressor system consists of two units with a rated pressure of 5MPa and a rated air volume of 1m 3 / min, rated power 22KW high pressure air compressor unit, and two units with rated pressure 3MPa and rated air volume 2m 3 / min, low-pressure air compressor unit with a rated power of 22KW.

[0099] During the well washing process, when the low-value water pressure of the dynamic water level is less than 2.2MPa, the well washing method uses two low-pressure air compressors to repeatedly wash the well intermittently. With the help of the bottom hole pressure measured by the third sensor 300, the well washing time is determined to be 20-25 minutes according to the real-time change of the dynamic water level, and then stop for 30 minutes. Compared with washing the well for 30 minutes and stopping for 30 minutes, the method reduces the operating time of the air compressor, reduces the operating power consumption, and improves the well washing efficiency of in-situ leaching uranium.

[0100] For conventional well washing, 6 units with a rated pressure of 5MPa and a rated air volume of 1m 3 / min, and an air compressor unit with a rated power of 22KW. The present invention saves the investment of two high-pressure air compressors and reduces the rated power of the air compressor by 44KW by configuring the air compressor unit at high and low speeds, and has significant work efficiency and economic efficiency.

[0101] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0102] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A well washing system for in-situ leaching of uranium, characterized in that: include: An air compressor system, the air compressor system comprising a high-pressure air compressor unit (1) and a low-pressure air compressor unit (2), the high-pressure air compressor unit (1) comprising at least one high-pressure air compressor, and the low-pressure air compressor unit (2) comprising at least one low-pressure air compressor; A pipeline system, wherein an air circuit control structure is arranged on the pipeline system, and the pipeline system further comprises a first air inlet pipeline, a second air inlet pipeline, a third air inlet pipeline, a first air outlet pipeline and a second air outlet pipeline, a high-pressure air bag (3) is arranged between the first air inlet pipeline and the first air outlet pipeline, a first pressure sensor (100) is arranged on the high-pressure air bag (3), a low-pressure air bag (4) is arranged between the second air inlet pipeline and the second air outlet pipeline, a second pressure sensor (200) is arranged on the low-pressure air bag (4), the first air outlet pipeline and the second air outlet pipeline are connected to each other and then connected to the top of a downhole air duct (6), and a third pressure sensor (300) is arranged at the bottom of the downhole air duct (6); A control system (5), wherein the air compressor system, the air path control structure, the first pressure sensor (100), the second pressure sensor (200) and the third pressure sensor (300) are electrically connected to the control system (5).

2. A well washing system for in-situ leaching of uranium according to claim 1, characterized in that: The gas circuit control structure comprises a one-way valve group and a solenoid valve group, the one-way valve group comprises a first one-way valve (71), a second one-way valve (72), a third one-way valve (73), a fourth one-way valve (74) and a fifth one-way valve (75), and the solenoid valve group comprises a first solenoid valve (81), a second solenoid valve (82), a third solenoid valve (83), a fourth solenoid valve (84) and a fifth solenoid valve (85); The first one-way valve (71) and the first solenoid valve (81) are arranged on the first air intake pipeline, and a first connection point is arranged between the first solenoid valve (81) and the high-pressure air bag (3); The second one-way valve (72) and the second solenoid valve (82) are arranged on the second air intake pipeline, and a second connection point is arranged between the second one-way valve (72) and the second solenoid valve (82); One end of the third air intake pipeline is in communication with the first connection point, the other end of the third air intake pipeline is in communication with the second connection point, and the third one-way valve (73) and the third solenoid valve (83) are arranged on the third air intake pipeline; The fourth one-way valve (74) and the fourth solenoid valve (84) are arranged on the first air outlet pipeline, and the fifth one-way valve (75) and the fifth solenoid valve (85) are arranged on the second air outlet pipeline.

3. A well washing method for in-situ leaching of uranium, characterized in that: A well washing system for in-situ leaching of uranium as claimed in claim 1 is used, comprising: The underground air pipe (6) is placed underground until the bottom of the underground air pipe (6) is set at a horizontal position of the underground ore layer, and the third pressure sensor (300) is used to collect the real-time underground pressure corresponding to the bottom of the underground air pipe (6); Rapid gas storage stage: the control system (5) controls the high-pressure air compressor unit (1) and the low-pressure air compressor unit (2) to start at the same time, and the second solenoid valve (82), the fifth one-way valve (75) and the fifth solenoid valve (85) in the gas path control structure are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state, and the air is delivered to the underground air pipe (6) through the high-pressure air bag (3); First control state: when the pressure measured by the first pressure sensor (100) reaches the rated pressure of the low-pressure air compressor unit (2), the control system (5) controls the closing of the third one-way valve (73) and the third solenoid valve (83) in the air path control structure, and simultaneously opens the second solenoid valve (82), so that the low-pressure air compressor unit (2) inflates the low-pressure air bag (4); Second control state: when the pressure measured by the second pressure sensor (200) reaches the rated pressure of the low-pressure air bag (4), the control system (5) controls the low-pressure air compressor unit (2) to stop working, and in the air path control structure, the second one-way valve (72), the second solenoid valve (82), the third one-way valve (73), the third solenoid valve (83), the fifth one-way valve (75) and the fifth solenoid valve (85) are in a closed state, and the remaining solenoid valves and the remaining one-way valves are in an open state; One-time well washing: when the real-time downhole pressure of the third pressure sensor (300) is greater than the preset first blowout pressure value, the high-pressure air compressor unit (1) continues to pressurize until the fluid in the well is sprayed to the ground; thereafter, when the real-time downhole pressure of the third pressure sensor (300) is less than the pressure value of the second pressure sensor (200), the control system (5) controls the second solenoid valve (82) and the fifth solenoid valve (85) to be in an open state, and the high-pressure air compressor unit (1) and the low-pressure air compressor unit (2) jointly supply air to the well, thereby realizing one-time well washing in the well.

4. A well washing method for in-situ leaching of uranium according to claim 3, characterized in that: After a well wash, intermittent well wash is performed according to the real-time downhole pressure of the third pressure sensor (300), the preset low dynamic water level value and the preset second blowdown pressure value, including: When the real-time downhole pressure of the third pressure sensor (300) is less than or equal to the low value of the dynamic water level, the control system (5) controls the closing of the fourth solenoid valve (84) and the fifth solenoid valve (85), controls the high-pressure air compressor unit (1) to supply air to the high-pressure air bag (3) to the rated pressure, and controls the low-pressure air compressor unit (2) to supply air to the low-pressure air bag (4) to the rated pressure; When the water level in the well rises and the real-time downhole pressure of the third pressure sensor (300) is greater than the second blowdown pressure value, the control system (5) controls the low-pressure air compressor unit (2) to operate, and in the air circuit control structure, the second one-way valve (72), the second solenoid valve (82), the fifth one-way valve (75) and the fifth solenoid valve (85) are in an open state, and the remaining solenoid valves and the remaining one-way valves are in a closed state, so that the low-pressure air compressor unit (2) continues to operate and intermittent well washing is performed in the well within a preset time corresponding to a preset low value of the dynamic water level.

5. A well washing method for in-situ leaching of uranium according to claim 3, characterized in that: Before placing the underground air duct (6) underground, the process includes: determining the rated pressure of the high-pressure air compressor unit (1), wherein the rated pressure of the high-pressure air compressor unit (1) is calculated as: Obtain the absolute elevation of the static water level above the ore layer, the absolute elevation of the ore layer and the well washing resistance; The absolute elevation of the static water level above the ore layer and the absolute elevation of the ore layer are solved by a preset hydrostatic pressure model to obtain the bottom hole hydrostatic pressure; The bottom hole hydrostatic pressure and the well-washing resistance are solved using a preset high-pressure air compressor unit calculation model to obtain the rated pressure of the high-pressure air compressor unit (1).

6. A well washing method for in-situ leaching of uranium according to claim 5, characterized in that: In obtaining the well-washing resistance, the calculation of the well-washing resistance is: In the above formula, △P 阻 represents the well washing resistance, in MPa; λ represents the friction resistance coefficient; V represents the average flow velocity in the underground air duct, in m / s; ρ 空 Indicates air density in kg / m 3 ; L is the length of the underground air duct, in m; D is the inner diameter of the underground air duct, in m.

7. A well washing method for in-situ leaching of uranium according to claim 5, characterized in that: The absolute elevation of the static water level above the ore layer and the absolute elevation of the ore layer are solved by a preset hydrostatic pressure model to obtain the bottom hole hydrostatic pressure, wherein the hydrostatic pressure model is: In the above formula, P 静 Represents the bottom water pressure in MPa; ρ 水 Indicates the density of water in kg / m 3 ; g is the acceleration due to gravity, in m / s 2 ; H1 is the absolute elevation of the static water level above the ore layer, in m; H2 is the absolute elevation of the ore layer, in m.

8. A well washing method for in-situ leaching of uranium according to claim 5, characterized in that: The bottom-hole hydrostatic pressure and the well-washing resistance are solved by using a preset high-pressure air compressor unit calculation model to obtain the rated pressure of the high-pressure air compressor unit (1), wherein the high-pressure air compressor unit calculation model is: P 10 =P 静 +△P 阻 +K1; In the above formula, P 10 Indicates the rated pressure of the high-pressure air compressor unit (1), P 静 Indicates the bottom water pressure, △P 阻 It represents the well washing resistance, K1 represents the first excess starting pressure, and its value range is 0.2-1.

0. The units of the above parameters are all MPa.

9. A well washing method for in-situ leaching of uranium according to claim 3, characterized in that: Before placing the underground air duct (6) underground, the method further includes: determining the rated pressure of the low-pressure air compressor unit (2), wherein the rated pressure of the low-pressure air compressor unit (2) is calculated as: Obtain the absolute elevation of the dynamic water level, the absolute elevation of the ore layer and the well washing resistance; The absolute elevation of the dynamic water level and the absolute elevation of the ore layer are solved by a preset dynamic water pressure model to obtain the bottom hole dynamic water level pressure; wherein the dynamic water pressure model is: In the above formula, P 动 Indicates the dynamic water level pressure at the bottom of the well, in MPa; ρ 水 Indicates the density of water in kg / m 3 ; g is the acceleration due to gravity, in m / s 2 ;H 31 is the dynamic water level height, in m; H2 is the absolute elevation of the ore layer, in m; The bottom well dynamic water level pressure and the well-washing resistance are solved by using a preset low-pressure air compressor unit calculation model to obtain the rated pressure of the low-pressure air compressor unit (2).

10. A well washing method for in-situ leaching of uranium according to claim 9, characterized in that: The bottom well dynamic water level pressure and the well washing resistance are solved by using a preset low-pressure air compressor unit calculation model to obtain the rated pressure of the low-pressure air compressor unit (2), wherein the low-pressure air compressor unit calculation model is: P 20 =P 动 +△P 阻 +K2; In the above formula (5), P 20 Indicates the rated pressure of low-pressure air compressor unit 2, P 动 Indicates the dynamic water level pressure at the bottom of the well, △P 阻 represents the well washing resistance, K2 represents the second excess starting pressure, and its value range is 0.1-0.

5. The units of the above parameters are all MPa.

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