Multi-heat-source cooperative preheating mine air inlet flow system and adjusting method

Abstract

The invention discloses a multi-heat-source cooperative preheating mine air inlet flow system and an adjusting method. The multi-heat-source cooperative preheating mine air inlet flow system comprises an air inlet laneway, an air compressor waste heat recovery unit, a ground temperature preheating unit, a heater unit and a temperature monitoring unit. A wellhead building with an adjustable air window is arranged at an inlet of the air inlet roadway; the air compressor waste heat recovery unit comprises an air compressor, a pipeline for connecting the air compressor with the inlet of the air inlet roadway, and a waste heat fan arranged in the pipeline; the ground temperature preheating unit comprises a shallow goaf filled with barren rock, a shallow waste laneway connecting the goaf and the air inlet laneway, and a ground temperature preheating fan and a ground temperature preheating air door which are arranged at the joint; the heater unit unit comprises a heating unit arranged on the ground and a pipeline for connecting the heating unit with the inlet of the air inlet laneway; the temperature monitoring unit comprises temperature sensors which are mounted below a laneway joint and on the ground; all the units are cooperatively connected with an inlet of an air inlet laneway through pipelines, and multi-heat-source graded preheating is achieved. According to the system, a multi-stage cooperative preheating system of the air compressor waste heat, the ground temperature rock heat and the heater unit is constructed, and energy gradient utilization and cost optimization are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of mine ventilation, and specifically relates to a multi-heat-source collaborative preheating system for mine intake air flow and an adjustment method thereof. Background Art

[0002] Underground mining operations in mines must continuously supply fresh air for workers to breathe, discharge foul air, and regulate the underground climate. In cold and high-altitude areas, the surface air temperature is low in winter. When low-temperature air directly enters the underground, on the one hand, it is easy to cause freezing of the shaft, seriously affecting the safe operation of the equipment in the shaft and threatening the lives of personnel; on the other hand, the low-temperature environment is not conducive to underground operations, affecting the health of workers and resulting in reduced production efficiency. Article 6.6.1.5 of the "Safety Regulations for Metal and Non-Metal Mines" (GB 16423-2020) in China stipulates that the air temperature in the intake airway should not be lower than 2°C. Therefore, when the temperature of the intake air flow entering the underground is lower than 2°C, the intake air flow must be preheated.

[0003] Currently, there are two commonly used methods for preheating the intake air flow. One is to use shallow abandoned mine roadways and goafs to preheat the incoming air, that is, the geothermal preheating method; the other is to install a heater unit at the intake to preheat the air flow, that is, the heater preheating method. Both of the above methods have certain defects. The preheating capacity of the geothermal preheating method mainly depends on the quantity of available abandoned mine roadways and goafs and the temperature of their surrounding rocks, and its ability to preheat the intake air flow is easily limited. While the heater preheating method requires the installation of heaters, and the operation energy consumption of the heaters is high, which easily causes a large increase in production costs.

[0004] In addition, in the case of no preheating of the air flow, the temperature of the intake air flow entering the underground is determined by the temperature of the surface air, and the temperature of the surface air changes dynamically with time and seasons. Without considering the dynamic change of the intake air flow temperature, it is difficult to accurately control the temperature of the preheated air flow, which easily causes energy waste or insufficient preheated air flow temperature. Summary of the Invention

[0005] The main purpose of the present invention is to provide a multi-heat-source collaborative preheating system for mine intake air flow and an adjustment method thereof with a significantly reduced comprehensive energy consumption and good system stability.

[0006] The multi-heat-source collaborative preheating system for mine intake air flow provided by the present invention includes an intake airway, an air compressor waste heat recovery unit, a geothermal preheating unit, a heater unit, and a temperature monitoring unit; a wellhead building with an adjustable air window is arranged at the entrance of the intake airway; the air compressor waste heat recovery unit includes an air compressor, a pipeline connecting the air compressor and the entrance of the intake airway, and a waste heat fan arranged in the pipeline; the geothermal preheating unit includes a shallow mined-out area filled with waste rock, a shallow old roadway connecting the mined-out area and the intake airway, a geothermal preheating fan and a geothermal preheating air door arranged at the connection; the heater unit includes a heating unit arranged on the ground and a pipeline connecting the unit and the entrance of the intake airway; the temperature monitoring unit includes temperature sensors installed below the connection of the roadway and on the ground; each unit is connected to the entrance of the intake airway through a pipeline in a collaborative manner to achieve multi-heat-source hierarchical preheating.

[0007] In an implementation manner of the above system, the shallow old roadway is formed by combining a vertical shaft, an inclined shaft, and a level roadway to form a ventilation passage.

[0008] In an implementation manner of the above system, the heating unit in the heater unit adopts a variable frequency controlled heating device.

[0009] In an implementation manner of the above system, the shallow mined-out area of the geothermal preheating unit is communicated with the ground through the shallow old roadway to form a cold air inlet passage.

[0010] In an implementation manner of the above system, the air compressor waste heat recovery unit includes multiple air compressors arranged in parallel.

[0011] In an implementation manner of the above system, the air compressor pipeline is a heat-insulating pipeline.

[0012] In an implementation manner of the above system, the heating unit is an air heater.

[0013] In an implementation manner of the above system, a PLC automatic control system is configured, and its hardware includes an industrial control computer on the ground, a PLC base station, a temperature sensor, an execution terminal, and an alarm; the industrial control computer on the ground serves as the control center; the PLC base station is connected and communicates with the industrial control computer on the ground; the temperature sensor is connected to the PLC base station; the execution terminal includes an air compressor waste heat fan, a geothermal preheating air door, a geothermal preheating fan, a heater unit, and an adjustable air window of the wellhead building; each component of the execution terminal is independently connected in parallel to the PLC base station; the alarm is connected to the PLC base station.

[0014] A regulation method for the multi-heat-source collaborative preheating system for mine intake air flow using any one of the above, the specific steps are as follows:

[0015] S1. Conduct temperature detection and set an initial judgment;

[0016] The temperature sensor is set to monitor the air flow temperature T in real time;

[0017] The PLC system sets the target temperature threshold range to 2 - 5 °C. When T < 2 °C, the preheating system is triggered to start. When T > 5 °C, the heat source is triggered to turn off;

[0018] S2. When it is judged in step S1 that the temperature is lower than the set value, start the air compressor heat source and make a judgment on the air compressor heat source;

[0019] When the air flow temperature T is lower than 2 °C for the first time and the air compressor is in the running state, turn on the air compressor waste heat fan and transport the waste heat to the entrance of the intake airway through the pipeline;

[0020] Calculate the heat supply Q of the air compressor waste heat 1 And compare it with the heat requirement kQ for preheating the air flow in the mine 0 Make a comparison;

[0021] The heat supply Q of the air compressor waste heat 1 Can be calculated according to the following formula:

[0022]

[0023] In the formula: Q 1 Is the preheating heat of the air compressor waste heat, with the unit of kW;

[0024] η 1 Is the waste heat utilization coefficient of the air compressor, with the range of 0.6 - 0.8;

[0025] η 2 Is the load factor, representing the ratio of the average actual power consumption per hour of the air compressor motor to the maximum actual power consumption, with the range of 0.5 - 0.8;

[0026] η 3 Is the simultaneous use factor, which is the ratio of the installed power used simultaneously to the total installed power, generally 0.5 - 1.0;

[0027] N is the rated installed power of the air compressor, with the unit of kW;

[0028] η is the efficiency of the air compressor motor, with the range of 0.85 - 0.95;

[0029] The heat requirement Q for preheating the air flow in the mine 0 Can be calculated according to the following formula:

[0030] Q 0 = 0.239Q b γC p (t 2 -t 1 )

[0031] In the formula: Q 0The heat required for preheating the air current in the mine, unit: kW;

[0032] Q b is the air inflow in the intake airway, unit: m 3 / s;

[0033] γ is the specific weight of cold air, unit: kg / m 3 ;

[0034] C p is the specific heat at constant pressure of air, unit: Kcal / (Kg℃);

[0035] t 1 is the temperature of cold air on the ground, unit: ℃;

[0036] t 2 is the temperature after air preheating, unit: ℃, take 2.0℃;

[0037] Compare Q 1 with kQ 0 k is the standby coefficient of the heat required for preheating the air current, range: 1.1 - 1.3;

[0038] If Q 1 is greater than kQ 0 , and at the same time when T > 5℃, then turn off the waste heat fan of the air compressor;

[0039] If Q 1 is less than kQ 0 , and at the same time when T < 2℃, then turn on the geothermal preheating heat source;

[0040] In other cases except the above two cases, keep the waste heat fan of the air compressor turned on;

[0041] S3. When it is judged in step S2 that the geothermal preheating heat source needs to be turned on, start the geothermal preheating heat source and conduct judgment on the geothermal preheating heat source; specifically as follows:

[0042] Open the geothermal preheating air door, start the geothermal preheating fan, and deliver the air preheated by geothermal energy to the entrance of the intake airway;

[0043] Calculate the heat supply Q 2 of geothermal preheating and compare it with the heat required for preheating the air current kQ 0 in the mine;

[0044] The heat supply Q 2 of geothermal preheating can be calculated by the following formula:

[0045]

[0046] In the formula: Q 2 is the geothermal preheating heat, unit: kW;

[0047] K τ is the unstable heat transfer coefficient between the surrounding rock and the air current, with the unit of kW / (m 2 ℃);

[0048] S is the area of the shallow abandoned mine roadways and shallow goafs used to preheat the intake air current with the ground temperature, with the unit of m 2 ;

[0049] t r is the average rock stratum temperature, with the unit of ℃;

[0050] t 1 is the ground cold air temperature, with the unit of ℃;

[0051] t 2 is the temperature after air preheating, with the unit of, taking 2.0℃;

[0052] Compare Q 1 +Q 2 with kQ 0 ;

[0053] If Q 1 +Q 2 is greater than kQ 0 , and at the same time when T>5℃, then turn off the ground temperature preheating fan and return to execute step S2;

[0054] If Q 1 +Q 2 is less than kQ 0 , and at the same time when T<2℃, then turn on the heating unit preheating heat source;

[0055] In other cases except the above two cases, keep the air compressor waste heat fan and the ground temperature preheating fan turned on;

[0056] S4. When it is judged in step S3 that the heating unit preheating heat source needs to be turned on, start the heating unit preheating heat source; specifically as follows:

[0057] Start the heater unit and initially operate at a low frequency;

[0058] Calculate the heat to be supplemented Q 3 to determine the operating power of the heating unit;

[0059] The heat to be supplemented Q 3 can be calculated according to the following formula:

[0060] Q 3 =kQ 0 -Q 1 -Q 2

[0061] Adjust the power of the heater unit in steps through the frequency converter to make the heat output by the heater unit equal to Q3 Same;

[0062] When the surface temperature rises and T > 5°C, turn off the preheating heat source of the heating unit and return to execute step S3;

[0063] S5. If the temperature is still lower than the set temperature after step S4 is executed, start the alarm to send an alarm and notify to suspend the operation.

[0064] The beneficial effects of the present invention are as follows:

[0065] 1. By constructing a multi-stage collaborative preheating system of air compressor waste heat, geothermal rock heat and heater units, the cascade utilization of energy and cost optimization are realized; the system preferentially uses air compressor waste heat for basic preheating, the geothermal preheating unit forms a stable heat exchange channel through transformation, and the heating unit only supplements heat in variable frequency mode under extreme working conditions; compared with the traditional single heat source system, the comprehensive energy consumption of this system is greatly reduced, overcoming the defect of limited preheating capacity of the geothermal method and significantly reducing the high energy consumption operation time of the heater.

[0066] 2. Adopt a dual-parameter regulation method that links heat calculation and temperature monitoring to effectively avoid frequent start and stop of the system; by calculating the heat supply of each heat source in real time and dynamically comparing it with the heat demand of the mine, combined with the inlet air temperature threshold range, an advanced regulation mechanism is formed; this method anticipates the heat source demand through heat balance and suppresses instantaneous fluctuation interference with the temperature buffer range. Compared with the simple temperature feedback system, the start and stop frequency of equipment is greatly reduced and the system stability is good. Description of the Drawings

[0067] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0068] Figure 2 It is a schematic structural diagram of the PLC automatic control system of the present invention. Detailed Embodiments

[0069] Next, the related technical solutions will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0070] As Figure 1 shown, the multi-heat-source collaborative preheating mine intake air flow system disclosed in this embodiment includes an intake airway 1, an air compressor waste heat recovery unit 2, a geothermal preheating unit 3, a heater unit 4 and a temperature monitoring unit 5. Each unit is connected to the intake airway entrance through a pipeline to realize multi-heat-source hierarchical preheating.

[0071] The intake airway 1, as the main passage of the mine intake air current, connects the ground with the underground ventilation network. At its entrance, a shaft building 11 is set up, and adjustable air windows are installed on the building to adjust the amount of cold air directly entering the airway.

[0072] The air compressor waste heat recovery unit 2 includes an air compressor 21, an air compressor waste heat fan 22, and an air compressor pipeline 23.

[0073] The air compressor 21 is arranged in the air compressor room at the entrance of the intake airway. The waste heat generated during operation is transported to the entrance of the intake airway through the air compressor pipeline 23, and an air compressor waste heat fan 22 is arranged in the pipeline to provide power for the flow of hot air in the air compressor pipeline.

[0074] The mine air compressor compresses air into high-pressure gas for underground rock drilling and compressed air self-rescue, and is an indispensable equipment for mine production operations. During the operation of the air compressor, heat can be stably dissipated. The supply of waste heat from the air compressor is relatively stable, and basically no additional costs are generated, which has good economy.

[0075] In this embodiment, the air compressor can be one or more, and is installed in the air compressor room.

[0076] The air compressor pipeline 23 is heat-insulated to prevent heat dissipation.

[0077] The geothermal preheating unit 3 includes a shallow goaf 31, waste rock 32, shallow old mine workings 33, a geothermal preheating fan 34, and a geothermal preheating air door 35.

[0078] The shallow goaf 31 is transformed into a preheating area, and large pieces of waste rock 32 are arranged inside for filling. On the one hand, it enables the cold air to have a more sufficient heat exchange with the rock mass and waste rock in the goaf, improving the ability to preheat the air current; on the other hand, after the waste rock is filled, it can support the shallow goaf and enhance the stability of the goaf.

[0079] One end of the shallow goaf 31 is connected to the ground surface through the shallow old mine workings 33 to facilitate the entry of cold air; the other end is connected to the intake airway 1 through the shallow old mine workings. The shallow old mine workings are composed of vertical shafts, inclined shafts, headings, and raises, etc.

[0080] A geothermal preheating fan 34 and a geothermal preheating air door 35 are installed at the connection between the shallow old mine workings 33 and the intake airway 1. The fan provides the air flow power, and the air door controls the opening and closing of the preheating channel. When it is necessary to utilize the geothermal preheated air current in the cold season, the air door is opened, and when it is not necessary to utilize the geothermal preheated air current in the summer, the air door is closed.

[0081] The depth of about 30 - 50 m underground is the constant temperature zone, and the temperature of the rock strata is not affected by seasonal temperature changes; below the constant temperature zone is the geothermal gradient zone, and the temperature of the rock strata continuously increases with the increase of depth.

[0082] When cold air passes through the shallow abandoned mine roadways and shallow goafs located in the constant temperature zone and the increasing temperature zone, heat exchange occurs between the rock mass and the air, causing the temperature of the air current to rise. Therefore, the geothermal temperature can be used as the heat source for preheating the incoming air current. Using the geothermal temperature as the heat source for preheating the incoming air current has the characteristics of stability and relatively low cost.

[0083] The heater unit 4 includes a heating unit 41 and a heating machine pipeline 42.

[0084] The heating unit 41 is arranged in the ground heater unit room, and the heated air is transported to the entrance of the intake airway through the heating machine pipeline 42.

[0085] The heating unit can use air heaters and hot air boilers, etc. The heating unit converts electrical energy or fossil energy into heat energy for preheating the incoming air current. It is started when the waste heat and geothermal temperature cannot meet the requirements, and the preheating capacity is controlled by adjusting the operating frequency through a frequency converter.

[0086] The temperature monitoring unit 5 is a temperature sensor, and there are two in total; one is installed 10 m below the connection between the shallow abandoned mine roadway 23 and the intake airway 1 for monitoring the temperature of the air current in the intake airway; the other is set on the ground for obtaining ground temperature data in real time.

[0087] Since the temperature of the cold air on the ground surface changes dynamically with time and seasons, in order to make this preheating system adapt to this dynamic change, ensure the stability of the temperature of the incoming air current in the mine after preheating, and at the same time reduce the cost of preheating the incoming air current and the management difficulty of the multi-heat-source combined preheating incoming air current system, a supporting PLC automatic control system is set up.

[0088] As Figure 2 shown, the PLC automatic control system supporting this preheating system includes a ground industrial control computer, a PLC base station, a temperature sensor, an execution terminal, and an alarm.

[0089] The ground industrial control computer serves as the control center for data reception, logical operation, and instruction issuance.

[0090] The PLC base station is connected and communicates with the ground industrial control computer, and is responsible for collecting sensor data and controlling the execution terminal.

[0091] The temperature sensor is connected to the PLC base station and uploads temperature data in real time.

[0092] The execution terminal includes an air compressor waste heat fan, a geothermal preheating air door, a geothermal preheating fan, a heater unit, and an adjustable air window for the wellhead building; each component is independently connected in parallel with the PLC base station and receives start-stop and frequency adjustment instructions;

[0093] The alarm is connected to the PLC base station and triggers an audible and visual alarm after receiving the base station instruction to respond to abnormal signals.

[0094] A method for regulating the temperature of the mine intake air flow using the above-mentioned preheating system is as follows:

[0095] S1. Conduct temperature detection and set initial judgment; specifically as follows:

[0096] The air flow temperature T is monitored in real time through a temperature sensor set 10 m below the entrance of the intake airway.

[0097] The PLC system sets the target temperature threshold range as 2 - 5 °C. When T < 2 °C, the preheating system is triggered to start. When T > 5 °C, the heat source is triggered to turn off.

[0098] S2. When it is judged in step S1 that the temperature is lower than the set value, start the air compressor heat source and conduct judgment on the air compressor heat source; specifically as follows:

[0099] When the air flow temperature T is first lower than 2 °C and the air compressor is in operation, turn on the air compressor waste heat fan, and convey the waste heat to the entrance of the intake airway through the pipeline.

[0100] Calculate the heat supply Q of the air compressor waste heat 1 And compare it with the heat required for preheating the mine intake air flow kQ 0 For comparison;

[0101] The heat supply Q of the air compressor waste heat 1 Can be calculated by the following formula:

[0102]

[0103] In the formula: Q 1 Is the preheating heat of the air compressor waste heat, with the unit of kW;

[0104] η 1 Is the waste heat utilization coefficient of the air compressor, with the range of 0.6 - 0.8;

[0105] η 2 Is the load factor, representing the ratio of the average actual power consumption per hour of the air compressor motor to the maximum actual power consumption, with the range of 0.5 - 0.8;

[0106] η 3 Is the simultaneous use factor, which is the ratio of the installed power in simultaneous use to the total installed power, generally 0.5 - 1.0;

[0107] N is the rated installed power of the air compressor, with the unit of kW;

[0108] η is the efficiency of the air compressor motor, with the range of 0.85 - 0.95;

[0109] The heat required for preheating the mine intake air flow Q 0 Can be calculated by the following formula:

[0110] Q0 = 0.239Q b γC p (t 2 - t 1 )

[0111] Where: Q 0 is the heat required for preheating the mine air current, in kW;

[0112] Q b is the air inflow in the intake airway, in m 3 / s;

[0113] γ is the specific weight of cold air, in kg / m 3 ;

[0114] C p is the specific heat at constant pressure of air, in Kcal / (Kg℃);

[0115] t 1 is the temperature of cold air on the ground, in ℃, obtained by the ground temperature sensor;

[0116] t 2 is the temperature after air preheating, in, taken as 2.0℃;

[0117] Compare Q 1 with kQ 0 k is the standby coefficient of the heat required for preheating the air current, with a range of 1.1 - 1.3; Setting the standby coefficient can reserve a safety margin for the system, covering extreme weather or the condition of heat source attenuation, and improving the system reliability;

[0118] If Q 1 is greater than kQ 0 , and at the same time when T > 5℃, then turn off the waste heat fan of the air compressor;

[0119] If Q 1 is less than kQ 0 , and at the same time when T < 2℃, then turn on the ground temperature preheating heat source;

[0120] In other cases except the above two cases, keep the waste heat fan of the air compressor on;

[0121] S3. When it is judged in step S2 that the ground temperature preheating heat source needs to be turned on, start the ground temperature preheating heat source and conduct a judgment on the ground temperature preheating heat source; Specifically as follows:

[0122] Open the ground temperature preheating air door, start the ground temperature preheating fan, and deliver the air preheated by the ground temperature to the entrance of the intake airway;

[0123] Calculate the heat supply Q 2 provided by the ground temperature preheating and compare it with the heat required for preheating the mine air current kQ 0 ;

[0124] The heat supply Q for preheating by ground temperature 2 can be calculated by the following formula:

[0125]

[0126] In the formula: Q 2 is the heat for preheating by ground temperature, with the unit of kW;

[0127] K τ is the unstable heat transfer coefficient between the surrounding rock and the air current, with the unit of kW / (m 2 ℃);

[0128] S is the area of the shallow abandoned mine roadways and shallow goafs used for preheating the intake air current by ground temperature, with the unit of m 2 ;

[0129] t r is the average rock formation temperature, with the unit of ℃;

[0130] t 1 is the ground cold air temperature, with the unit of ℃;

[0131] t 2 is the temperature after air preheating, with the unit of, taking 2.0℃;

[0132] Compare Q 1 +Q 2 with kQ 0 ;

[0133] If Q 1 +Q 2 is greater than kQ 0 , and at the same time when T > 5℃, then turn off the ground temperature preheating fan and return to execute step S2;

[0134] If Q 1 +Q 2 is less than kQ 0 , and at the same time when T < 2℃, then turn on the heating unit preheating heat source;

[0135] In other cases except the above two cases, keep the air compressor waste heat fan and the ground temperature preheating fan on;

[0136] S4. When it is judged in step S3 that the heating unit preheating heat source needs to be turned on, start the heating unit preheating heat source; specifically as follows:

[0137] Start the heater unit and run it at a low frequency initially;

[0138] Calculate the heat Q 3 to be supplemented to determine the operating power of the heating unit;

[0139] The supplementary heat Q3 It can be calculated according to the following formula:

[0140] Q 3 = kQ 0 -Q 1 -Q 2

[0141] Adjust the power of the heater unit in steps through the frequency converter to make the heat output of the heater unit the same as Q 3 the same;

[0142] When the surface temperature rises and T > 5°C, turn off the preheating heat source of the heating unit and return to execute step S3.

[0143] S5. When the temperature is still lower than the set temperature after step S4 is executed, start the alarm to give an alarm and notify to suspend the operation.

[0144] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the above embodiments have been described in detail, those skilled in the art can still modify the technical solutions recorded in the above embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-heat source collaborative preheating mine air intake system, characterized by: It includes air intake shaft, air compressor waste heat recovery unit, ground temperature preheating unit, heater unit unit and temperature monitoring unit; A wellhead building with an adjustable wind window is set at the entrance of the air inlet shaft and tunnel; the air compressor waste heat recovery unit includes an air compressor, a pipeline connecting the air compressor and the entrance of the air inlet shaft and tunnel, and a waste heat fan arranged in the pipeline; the geothermal preheating unit includes a shallow goaf filled with waste rock, a shallow waste shaft and tunnel connecting the goaf and the air inlet shaft and tunnel, a geothermal preheating fan and a geothermal preheating damper arranged at the connection; the heater unit unit includes a heating unit arranged on the ground and a pipeline connecting the unit and the entrance of the air inlet shaft and tunnel; the temperature monitoring unit includes a temperature sensor installed below the shaft and tunnel connection and on the ground; Each unit is cooperatively connected with the air inlet shaft entrance through pipelines to achieve multi-heat source graded preheating.

2. The multi-heat source cooperative preheating mine air intake system according to claim 1, characterized in that: The shallow abandoned shafts and tunnels are composed of vertical shafts, inclined shafts and horizontal tunnels to form a ventilation channel.

3. The multi-heat source coordinated preheating mine air intake system according to claim 1, characterized in that: The heating unit in the heater unit unit adopts a variable frequency controlled heating device.

4. The multi-heat source cooperative preheating mine air intake system according to claim 1, characterized in that: The shallow goaf of the geothermal preheating unit is connected to the ground surface through shallow abandoned shafts and tunnels to form a cold air entry channel.

5. The multi-heat source cooperative preheating mine air intake system according to claim 1, characterized in that: The air compressor waste heat recovery unit comprises a plurality of air compressors arranged in parallel.

6. The multi-heat source cooperative preheating mine air intake system according to claim 1, characterized in that: The air compressor pipeline is a heat-insulated pipeline.

7. The multi-heat source coordinated preheating mine air intake system according to claim 1, characterized in that: The heating unit is an air heater.

8. The multi-heat source coordinated preheating mine air intake system according to claim 1, characterized in that: It is equipped with a PLC automatic control system, whose hardware includes ground industrial computers, PLC base stations, temperature sensors, execution terminals and alarms; The ground industrial computer serves as the control center; the PLC base station is connected and communicated with the ground industrial computer; the temperature sensor is connected to the PLC base station; the execution terminal includes the air compressor waste heat fan, geothermal preheating damper, geothermal preheating fan, heater unit and wellhead building regulating window; each component of the execution terminal is independently connected in parallel with the PLC base station; the alarm is connected to the PLC base station.

9. A method for regulating a mine air inlet system using multiple heat sources for collaborative preheating according to any one of claims 1 to 8, characterized in that: The specific steps are as follows: S1. Perform temperature detection and set initial judgment; The wind flow temperature T is monitored in real time through the set temperature sensor; The PLC system sets the target temperature threshold range to 2-5°C. When T < 2°C, the preheating system is triggered to start, and when T > 5°C, the heat source is triggered to shut down. S2. When the temperature is lower than the set value as determined in step S1, the air compressor heat source is started and the air compressor heat source is judged; When the air flow temperature T is lower than 2°C for the first time and the air compressor is in operation, turn on the air compressor waste heat fan to transport the waste heat to the entrance of the air inlet shaft through the pipeline; Calculate the heat supply Q1 of the air compressor waste heat and compare it with the heat required for mine preheating airflow kQ0; The heat Q1 supplied by the waste heat of the air compressor can be calculated as follows: Where: Q1 is the preheating heat of the air compressor waste heat, unit is kW; η1 is the waste heat utilization coefficient of the air compressor, ranging from 0.6 to 0.8; η2 is the load factor, which represents the ratio of the average actual power consumption of the air compressor motor per hour to the maximum actual power consumption, ranging from 0.5 to 0.8; η3 is the simultaneous use coefficient, which is the ratio of the installed power used simultaneously to the total installed power, generally 0.5 to 1.0; N is the installed rated power of the air compressor, in kW; η is the air compressor motor efficiency, ranging from 0.85 to 0.95; The heat required for mine preheating air flow Q0 can be calculated as follows: Q0=0.239Q b γC p (t2-t1) Where: Q0 is the heat required for preheating airflow in the mine, in kW; Q b is the air volume of the air shaft, in m 3 / s; γ is the cold air weight, in kg / m 3 ; C p is the specific heat of air at constant pressure, unit is Kcal / (Kg℃); t1 is the ground cold air temperature, in °C; t2 is the temperature of air after preheating, in units of , and is taken as 2.0℃; Compare Q1 with kQ0, where k is the heat reserve coefficient required for preheating airflow, ranging from 1.1 to 1.3; If Q1 is greater than kQ0 and T>5℃, turn off the air compressor waste heat fan; If Q1 is less than kQ0 and T is less than 2°C, the ground temperature preheating heat source is turned on; In other cases except the above two, keep the air compressor waste heat fan on; S3. When step S2 determines that the ground temperature preheating heat source needs to be turned on, the ground temperature preheating heat source is started and the ground temperature preheating heat source is judged; the details are as follows: Open the ground temperature preheating damper, start the ground temperature preheating fan, and transport the ground temperature preheated air to the entrance of the air inlet shaft; Calculate the heat supply Q2 for ground temperature preheating and compare it with the heat required for mine preheating airflow kQ0; The heat supply Q2 of ground temperature preheating can be calculated as follows: Where: Q2 is the ground temperature preheating heat, unit is kW; K τ is the unstable heat transfer coefficient between the surrounding rock and the wind flow, in kW / (m 2 ℃); S is the area of ​​shallow abandoned shafts and shallow goafs that are used to preheat the incoming air flow using ground temperature, in m 2 ; t r is the average rock formation temperature, in °C; t1 is the ground cold air temperature, in °C; t2 is the temperature of air after preheating, in units of , and is taken as 2.0℃; Compare Q1+Q2 with kQ0; If Q1+Q2 is greater than kQ0 and T>5°C, turn off the ground temperature preheating fan and return to step S2; If Q1+Q2 is less than kQ0 and T is less than 2°C, the heating unit is turned on to preheat the heat source; In other cases except the above two, keep the air compressor waste heat fan and ground temperature preheating fan turned on; S4. When step S3 determines that the heating unit preheating heat source needs to be turned on, the heating unit preheating heat source is turned on; the details are as follows: Start the heater unit and initially run it at a low frequency; Calculate the required additional heat Q3 to determine the operating power of the heating unit; The supplementary heat Q3 can be calculated as follows: Q3=kQ0-Q1-Q2 The power of the heater unit is adjusted in stages by the frequency converter to make the heat output of the heater unit the same as that of Q3; When the surface temperature rises and T>5°C, turn off the preheating heat source of the heating unit and return to step S3; S5. When the temperature is still lower than the set temperature after step S4 is executed, the alarm is activated to sound an alarm and notify the operation to be suspended.

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