阅读说明：本技术 一种寒冷矿区回风井余热回收综合利用系统及方法 (System and method for recycling waste heat of return air shaft in cold mine area ) 是由 徐宇 李孜军 王君健 陈寅 贾敏涛 李蓉蓉 王巧莉 章梦胜 张修智 于 2021-08-05 设计创作，主要内容包括：本发明公开了一种寒冷矿区回风井余热回收综合利用系统及方法,该装置包括余热回收预热机构和半导体热电转换机构；该方法包括步骤一、回风过滤网的安装；二、回风井内矿井回风的过滤；三、矿井回风余热的回收和进风预热；四、判断进风井内的风流温度是否大于设定的最低温度；五、半导体热电转换机构对蓄电池进行充电；六、半导体热电转换机构对进风加温；七、再次判断进风井内的风流温度是否大于设定的最低温度；八、电辅助加热器对进风加温。本发明能够对回风余热进行回收,同时能够通过回收的余热进行进风预热和温差发电,实现了在加热进风的同时进行发电的能源综合利用,提高了能量的利用率,实现了物尽其用,节约了矿井建设的固有资产。(The invention discloses a waste heat recovery comprehensive utilization system and method for a return air shaft in a cold mining area, wherein the device comprises a waste heat recovery preheating mechanism and a semiconductor thermoelectric conversion mechanism; the method comprises the steps of firstly, mounting a return air filter screen; secondly, filtering mine return air in a return air well; thirdly, recovering the waste heat of return air of the mine and preheating the inlet air; judging whether the temperature of the air flow in the air inlet well is higher than the set lowest temperature or not; fifthly, charging the storage battery by the semiconductor thermoelectric conversion mechanism; sixthly, heating the inlet air by the semiconductor thermoelectric conversion mechanism; seventhly, judging whether the temperature of the air flow in the air inlet well is higher than the set lowest temperature again; eighthly, heating the inlet air by an electric auxiliary heater. The invention can recover the waste heat of the return air, and can simultaneously carry out air inlet preheating and thermoelectric generation through the recovered waste heat, thereby realizing the comprehensive utilization of energy sources for power generation while heating the inlet air, improving the utilization rate of energy, making the best use of things and saving the inherent assets of mine construction.)

1. The utility model provides a cold mining area return air shaft waste heat recovery comprehensive utilization system which characterized in that: the waste heat recovery preheating device comprises a return air shaft (1), an air inlet shaft (7), a waste heat recovery preheating mechanism connected between the return air shaft (1) and the air inlet shaft (7) and a thermoelectric conversion system arranged in the air inlet shaft (7) and matched with the waste heat recovery preheating mechanism, wherein the thermoelectric conversion system is connected with a storage battery (16) and an external power supply (10) through a single-pole double-throw switch (20), a voltage stabilizer (15) is connected between the output end of the thermoelectric conversion system and the storage battery (16), a return air fan (2) is arranged in the return air shaft (1), an air inlet fan (13) and an electric auxiliary heater (11) are arranged in the air inlet shaft (7), and the thermoelectric conversion system is positioned between the electric auxiliary heater (11) and the air inlet fan (13);

the waste heat recovery preheating mechanism comprises a plurality of gravity type heat pipes (5), the thermoelectric conversion system comprises a plurality of semiconductor thermoelectric conversion mechanisms (9) which are connected in series, the number of the semiconductor thermoelectric conversion mechanisms (9) is equal to that of the gravity type heat pipes (5), the semiconductor thermoelectric conversion mechanisms correspond to the gravity type heat pipes (5) one by one, a heat pipe heat insulation layer (6) is arranged on the outer side of each gravity type heat pipe (5), each gravity type heat pipe (5) comprises an evaporation section (5-1), a condensation section (5-2) and a heat exchange section (5-3), the evaporation section (5-1) is located in an air return well (1), the condensation section (5-2) is located in an air inlet well (7), and one end of each semiconductor thermoelectric conversion mechanism (9) is attached to the condensation section (5-2);

a temperature sensor (12) is arranged in the air inlet shaft (7), and the electric auxiliary heater (11), the single-pole double-throw switch (20) and the temperature sensor (12) are all connected with the controller (14).

2. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: and a return air heat-insulating layer (3) is arranged on the wall of the return air shaft (1), and an air inlet heat-insulating layer (8) is arranged on the wall of the air inlet shaft (7).

3. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: the air return well is characterized in that an air return filter screen (4) is arranged in the air return well (1), and the air return filter screen (4) is located between the air return fan (2) and the waste heat recovery preheating mechanism.

4. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: the heat pipe heat-insulation system is characterized in that heat exchange fins (5-4) are arranged on the evaporation section (5-1), the outer wall of the evaporation section (5-1) is wrapped with heat-absorbing materials (5-5), the heat exchange section (5-3) is filled with heat exchange working media, and the heat pipe heat-insulation layer (6) is wrapped outside the heat exchange section (5-3).

5. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: the storage battery (16) is connected with mine lighting equipment (18) and a mine electrical appliance (19) through an inverter (17);

the controller (14), the storage battery (16) and the inverter (17) are all arranged in an electric storage utilization control room outside the mine.

6. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: the semiconductor thermoelectric conversion mechanism (9) comprises a P-type semiconductor (9-1), an N-type semiconductor (9-2) and a metal guide strip (9-3), wherein the P-type semiconductor (9-1) and the N-type semiconductor (9-2) are connected in series through the metal guide strip (9-3).

7. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: one end of the semiconductor thermoelectric conversion mechanism (9) attached to the condensation section (5-2) is a C-shaped end, and the C-shaped end of the semiconductor thermoelectric conversion mechanism (9) is buckled on the condensation section (5-2) of the gravity type heat pipes (5).

8. The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area according to claim 1, characterized in that: the moving contact of the single-pole double-throw switch (20) is connected with the input end of the semiconductor thermoelectric conversion mechanism, the first stationary contact of the single-pole double-throw switch (20) is connected with the storage battery (16), and the second stationary contact of the single-pole double-throw switch (20) is connected with the external power supply (10).

9. A method for comprehensively utilizing the waste heat of the return air shaft of the cold mine area by the system of claim 1, which is characterized by comprising the following steps:

step one, mounting a return air filter screen: a return air filter screen (4) is arranged in the return air shaft (1), and the return air filter screen (4) is positioned between the return air fan (2) and the waste heat recovery preheating mechanism;

step two, filtering mine return air in a return air well: the return air fan (2) pumps mine return air containing a large amount of low-temperature heat energy entering the return air shaft (1) through the connecting roadway to a return air filter screen (4) for filtering, and then the mine return air flows to the waste heat recovery preheating mechanism;

step three, recovering waste heat of return air of the mine and preheating the inlet air: when mine return air filtered by the return air shaft (1) flows through the waste heat recovery preheating mechanism, heat is given to an evaporation section (5-1) of the gravity type heat pipe (5), so that a heat exchange working medium in the heat exchange section (5-3) is subjected to phase change and carries a large amount of heat energy to be transferred towards a condensation section (5-2), after the heat exchange working medium subjected to the phase change moves to the condensation section (5-2), the electric auxiliary heater (11) is closed, the heat of the heat exchange working medium is dissipated through the condensation section (5-2) to preheat inlet air, and meanwhile, the heat exchange working medium is subjected to phase change and returns to the evaporation section (5-1) along the pipe wall of the heat exchange section (5-3) under the action of gravity;

step four, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature: monitoring the temperature in the air inlet shaft (7) in real time through a temperature sensor (12), and executing a fifth step when the temperature in the air inlet shaft (7) is higher than the set lowest temperature; when the temperature in the air inlet shaft (7) is less than or equal to the set lowest temperature, executing a sixth step;

step five, charging the storage battery by the semiconductor thermoelectric conversion mechanism: the controller (14) controls the single-pole double-throw switch (20) to act, so that a plurality of semiconductor thermoelectric conversion mechanisms (9) connected in series and the storage battery (16) form a loop, the semiconductor thermoelectric conversion mechanisms (9) generate electromotive force under the action of the Seebeck effect, and the electromotive force is stably output under the action of the voltage stabilizer (15) and is stored in the storage battery (16);

sixthly, heating the inlet air by the semiconductor thermoelectric conversion mechanism: the controller (14) controls the single-pole double-throw switch (20) to act, so that the semiconductor thermoelectric conversion mechanism and the external power supply (10) form a loop, the Peltier effect is utilized to promote the gravity type heat pipe heat exchanger (5) to absorb return air waste heat, and heat is released from one end, far away from the condensation section (5-2), of the semiconductor thermoelectric conversion mechanism to heat inlet air in the air inlet well (7);

step seven, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature again: when the temperature in the air inlet shaft (7) is higher than the set lowest temperature, returning to the third step; when the temperature in the air inlet shaft (7) is less than or equal to the set lowest temperature, executing the step eight;

step eight, heating the inlet air by an electric auxiliary heater: the electric auxiliary heater (11) is started to heat the inlet air.

10. The method of claim 9, wherein: and in the fifth step, when the storage battery is charged, one end, attached to the condensing section (5-2), of the semiconductor thermoelectric conversion mechanism (9) is heated, so that the temperature is increased, and further, a temperature difference is generated between one end, attached to the condensing section (5-2), of the semiconductor thermoelectric conversion mechanism (9) and the other end, positioned in a cold region, of the semiconductor thermoelectric conversion mechanism (9) and used for directly blowing the inlet air, and further, an electromotive force is generated under the action of the Seebeck effect.

Technical Field

The invention belongs to the technical field of mine waste heat recycling and energy saving, and particularly relates to a system and a method for recycling waste heat of a return air shaft in a cold mine area comprehensively.

Background

The low temperature is a large factor for restricting the mining of the mine, and the air temperature of the air inlet shaft should not be lower than 2 ℃ as clearly indicated in the metallic and non-metallic mine safety regulations (GB 16423-Bu 2020) of China; below 2 deg.c, there should be air heating facility and no open fire should be used to directly heat the air entering the mine. The existing cold mine areas in China are more, on one hand, in northern areas of China, the environment temperature is low in winter due to high latitude, and the temperature of a mine air inlet is generally lower than 2 ℃ when the mine air inlet is not preheated; on the other hand, in recent years, the resource demand is gradually increased, mineral mining is gradually shifted to western regions, and the temperature is low due to high altitude at the mine, so that the phenomenon of frozen ice often occurs. Working under low temperature environment, staff and mechanical equipment's work efficiency descends by a wide margin, not only can restrict the smooth development of mineral resources, and the frozen ice falls and still threatens workman's life safety.

The main preheating measures adopted in the current mine include electric preheating, heating furnace preheating and the like, and for the high-altitude mine, the electric charge is high, and the difficulty in resource transportation is high. And a large amount of resources are consumed by preheating through the heating furnace, a great number of pollutants are generated, the greenhouse effect is caused, and the construction of green mines is not facilitated. The mine return air has the characteristics of large air quantity, constant return air temperature and the like, is an important low-temperature waste heat resource, and is widely applied to replacing a traditional hot blast stove to supply heat to a wellhead in recent years. However, most of the existing mine waste heat recovery devices use direct cooling type or spray type heat exchange, and the devices are heavy, high in building cost and high in failure rate. Although the heat pipe heat exchanger has extremely simple manufacturability and higher heat transfer performance and can be used for recycling waste heat existing in various media such as solid, liquid, gas and the like, the mine air inlet shaft and the mine air return shaft are usually far away from each other, so that the condition of poor preheating of inlet air sometimes occurs. In the existing research, heat exchange of the heat pipe can only carry out primary energy recovery, and refrigerating capacity cannot be adjusted, so that energy is wasted easily, overcooling or overheating occurs, and the body feeling comfort level of workers is affected. At present, the recovery and utilization of the waste heat of the return air of the mine are not complete, and the requirements of full utilization of resources, energy conservation and green mining cannot be met.

Disclosure of Invention

The invention aims to solve the technical problem of providing a waste heat recovery and comprehensive utilization system for a return air shaft in a cold mine area, which combines a gravity type heat pipe and a semiconductor thermoelectric conversion mechanism together to recover waste heat resources, wherein the gravity type heat pipe can generate heat through the recovered waste heat resources to preheat inlet air on one hand, and can also utilize the residual heat generated by the gravity type heat pipe to generate power through temperature difference of a semiconductor thermoelectric conversion mechanism on the other hand, so that the comprehensive utilization of the energy for generating power while heating the inlet air is realized, the utilization rate of the energy is improved, the semiconductor thermoelectric conversion mechanism can be used as a temperature difference power generation device, the heat exchange capacity of the gravity type heat pipe can be improved, and the semiconductor thermoelectric conversion mechanism can be used as an inlet air preheating device, so that the best use is realized, and inherent assets of mine construction are saved.

In order to solve the technical problems, the invention adopts the technical scheme that: the utility model provides a cold mining area return air shaft waste heat recovery comprehensive utilization system which characterized in that: the waste heat recovery preheating device comprises a return air shaft, an air inlet shaft, a waste heat recovery preheating mechanism connected between the return air shaft and the air inlet shaft and a thermoelectric conversion system arranged in the air inlet shaft and matched with the waste heat recovery preheating mechanism, wherein the thermoelectric conversion system is connected with a storage battery and an external power supply through a single-pole double-throw switch, a voltage stabilizer is connected between the output end of the thermoelectric conversion system and the storage battery, a return air fan is arranged in the return air shaft, an air inlet fan and an electric auxiliary heater are arranged in the air inlet shaft, and the thermoelectric conversion system is positioned between the electric auxiliary heater and the air inlet fan;

the waste heat recovery preheating mechanism comprises a plurality of gravity type heat pipes, the thermoelectric conversion system comprises a plurality of semiconductor thermoelectric conversion mechanisms which are connected in series, the number of the semiconductor thermoelectric conversion mechanisms is equal to that of the gravity type heat pipes, the semiconductor thermoelectric conversion mechanisms correspond to the gravity type heat pipes one by one, a heat pipe heat insulation layer is arranged on the outer side of each gravity type heat pipe, each gravity type heat pipe comprises an evaporation section, a condensation section and a heat exchange section, the evaporation section is located in a return air well, the condensation section is located in an air inlet well, and one end of each semiconductor thermoelectric conversion mechanism is attached to the condensation section;

and a temperature sensor is arranged in the air inlet shaft, and the electric auxiliary heater, the single-pole double-throw switch and the temperature sensor are all connected with the controller.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: and a return air heat-insulating layer is arranged on the wall of the return air shaft, and an air inlet heat-insulating layer is arranged on the wall of the air inlet shaft.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: and a return air filter screen is arranged in the return air shaft and is positioned between the return air fan and the waste heat recovery preheating mechanism.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: the heat pipe heat-insulating heat exchanger is characterized in that heat exchange fins are arranged on the evaporation section, a heat absorbing material is wrapped on the outer wall of the evaporation section, a heat exchange working medium is filled in the heat exchange section, and the heat pipe heat-insulating layer is wrapped outside the heat exchange section.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: the storage battery is connected with mine lighting equipment and mine electrical appliances through an inverter;

the controller, the storage battery and the inverter are all arranged in an electric power storage utilization control room outside the mine.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: the semiconductor thermoelectric conversion mechanism comprises a P-type semiconductor, an N-type semiconductor and a metal diversion strip, wherein the P-type semiconductor and the N-type semiconductor are connected in series through the metal diversion strip.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: one end, attached to the condensation section, of the semiconductor thermoelectric conversion mechanism is a C-shaped end, and the C-shaped end of the semiconductor thermoelectric conversion mechanism is buckled on the condensation section of the gravity type heat pipes.

Foretell cold mining area return air shaft waste heat recovery comprehensive utilization system, its characterized in that: the movable contact of the single-pole double-throw switch is connected with the input end of the semiconductor thermoelectric conversion mechanism, the first stationary contact of the single-pole double-throw switch is connected with the storage battery, and the second stationary contact of the single-pole double-throw switch is connected with an external power supply.

The invention also discloses a method for comprehensively utilizing the waste heat of the return air shaft in the cold mine area, which is characterized by comprising the following steps of:

step one, mounting a return air filter screen: a return air filter screen is arranged in the return air well, and is positioned between the return air fan and the waste heat recovery preheating mechanism;

step two, filtering mine return air in a return air well: the return air fan pumps the mine return air containing a large amount of low-temperature heat energy entering the return air well through the connecting roadway to a return air filter screen for filtering, and then the mine return air flows to the waste heat recovery preheating mechanism;

step three, recovering waste heat of return air of the mine and preheating the inlet air: when mine return air filtered by the return air shaft flows through the waste heat recovery preheating mechanism, heat is given to the evaporation section of the gravity type heat pipe, so that a heat exchange working medium in the heat exchange section is subjected to phase change and carries a large amount of heat energy to be transferred towards the condensation section;

step four, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature: monitoring the temperature in the air inlet well in real time through a temperature sensor, and executing the fifth step when the temperature in the air inlet well is higher than the set lowest temperature; when the temperature in the air inlet well is less than or equal to the set lowest temperature, executing a sixth step;

step five, charging the storage battery by the semiconductor thermoelectric conversion mechanism: the controller controls the single-pole double-throw switch to act, so that a plurality of semiconductor thermoelectric conversion mechanisms connected in series and the storage battery form a loop, the semiconductor thermoelectric conversion mechanisms generate electromotive force under the action of the Seebeck effect, and the electromotive force is stably output under the action of the voltage stabilizer and is stored in the storage battery;

sixthly, heating the inlet air by the semiconductor thermoelectric conversion mechanism: the controller controls the single-pole double-throw switch to act, so that the semiconductor thermoelectric conversion mechanism and an external power supply form a loop, the Peltier effect is utilized to promote the gravity type heat pipe heat exchanger to absorb return air waste heat, and heat is released from one end, far away from the condensation section, of the semiconductor thermoelectric conversion mechanism to heat inlet air in the air inlet well;

step seven, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature again: when the temperature in the air inlet well is higher than the set lowest temperature, returning to the third step; when the temperature in the air inlet well is less than or equal to the set lowest temperature, executing the step eight;

step eight, heating the inlet air by an electric auxiliary heater: and starting the electric auxiliary heater to heat the inlet air.

The above method is characterized in that: and fifthly, when the storage battery is charged, one end, attached to the condensation section, of the semiconductor thermoelectric conversion mechanism is heated, the temperature is increased, and then a temperature difference is generated between one end, attached to the condensation section, of the semiconductor thermoelectric conversion mechanism and the other end, located in a cold region, of the semiconductor thermoelectric conversion mechanism and used for directly blowing the inlet air, and further an electromotive force is generated under the action of the Seebeck effect.

Compared with the prior art, the invention has the following advantages:

1. according to the system adopted by the invention, the gravity type heat pipes are combined together to form the waste heat recovery preheating mechanism, the waste heat recovery preheating mechanism and the semiconductor thermoelectric conversion mechanism are combined together to recover and utilize the mine return air waste heat, the waste heat recovery preheating mechanism can fully utilize the low-temperature heat energy in the mine return air to preheat the mine inlet air, the semiconductor thermoelectric conversion mechanism can carry out thermoelectric generation on the residual heat generated by the waste heat recovery preheating mechanism, and further the electric energy is stored in the storage battery for standby application, the air inlet heating is not required to be carried out by adopting extra fuel in the whole process, the resource is saved, and the system is green and environment-friendly.

2. According to the system adopted by the invention, one end of the semiconductor thermoelectric conversion mechanism is attached to the condensation section of the gravity type heat pipe, when the heat converted by the gravity type heat pipe is not enough to support the requirement of preheating the inlet air, and the direct current is supplied to the semiconductor thermoelectric conversion mechanism through the external power supply, the semiconductor thermoelectric conversion mechanism can extract the heat attached to one end of the gravity type heat pipe and transfer the heat to the other end, so that the capacity of the gravity type heat pipe for absorbing the waste heat of the return air of the mine is enhanced, the heat exchange efficiency of the gravity type heat pipe can be further improved, and the energy utilization rate is improved.

3. According to the system adopted by the invention, the electric auxiliary heater is arranged in the air inlet shaft, when the recovered mine return air waste heat is not enough to preheat the inlet air, the inlet air can be heated in an auxiliary manner through the electric auxiliary heater, so that the condition that the low-temperature environment of the mine is caused by poor preheating of the inlet air is avoided, and the working efficiency is further reduced.

4. According to the method, when the waste heat of the return air of the mine is enough to preheat the inlet air, the gravity type heat pipe is used for heating the inlet air of the mine, the rest generated heat can be used for the semiconductor thermoelectric conversion mechanism to carry out thermoelectric generation, the generated electric energy is stored in the storage battery to supply power to all devices in the mine, and secondary recovery is carried out on the energy, so that the phenomenon of supercooling and overheating can be avoided when the gravity type heat pipe is used for heating the inlet air, and the energy resource can be fully utilized to prevent waste.

5. According to the method, when the waste heat of the return air of the mine is not enough to preheat the inlet air, the semiconductor thermoelectric conversion mechanism can still be comprehensively utilized except for temperature difference power generation, and when the heat is converted in seasons and the gravity type heat pipe heat exchange cannot meet the requirement of preheating the inlet air of the mine, the inlet air of the mine can be heated by arranging an external power supply and utilizing the Peltier effect of thermoelectric materials, so that the purposes of making the best use of things and reducing the additional economic expenditure can be achieved.

In summary, the gravity type heat pipe and the semiconductor thermoelectric conversion mechanism are combined together to recover the waste heat resource, on one hand, the gravity type heat pipe can preheat the inlet air by generating heat through the recovered waste heat resource, on the other hand, the residual heat generated by the gravity type heat pipe can be used for thermoelectric generation of the semiconductor thermoelectric conversion mechanism, so that the comprehensive utilization of energy for generating power while heating the inlet air is realized, the utilization rate of energy is improved, the semiconductor thermoelectric conversion mechanism can be used as a thermoelectric generation device, the heat exchange capability of the gravity type heat pipe can be improved, the gravity type heat pipe can be used as the inlet air preheating device, the best use is realized, and inherent assets of mine construction are saved.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

Fig. 1 is a usage state diagram of the waste heat recovery and comprehensive utilization system of the invention.

Fig. 2 is a heat exchange schematic diagram of the gravity type heat pipe of the present invention.

Fig. 3 is a schematic diagram of thermoelectric power generation of the semiconductor thermoelectric conversion mechanism of the present invention.

FIG. 4 is a schematic diagram of the heating of the inlet air of the semiconductor thermoelectric conversion device of the present invention.

Fig. 5 is a control block diagram of the present invention.

FIG. 6 is a block flow diagram of the method of the present invention.

Description of reference numerals:

1-return air shaft; 2-return air fan; 3-return air heat insulation layer;

4, return air filter screen; 5-gravity type heat pipe; 5-1-evaporation section;

5-2-condensation section; 5-3-heat exchange section; 5-4-heat exchange fins;

5-a heat absorbing material; 6-heat pipe thermal insulation layer; 7-an air inlet shaft;

8-air intake heat insulation layer; 9-semiconductor thermoelectric conversion mechanism; 9-1-P-type semiconductor;

9-2-N type semiconductor; 9-3-metal guide strips; 10-external power supply;

11-an electric auxiliary heater; 12-a temperature sensor; 13-air intake fan;

14-a controller; 15-a voltage stabilizer; 16-a storage battery;

17-an inverter; 18-mine lighting equipment; 19-a mining electrical appliance;

20-single pole double throw switch.

Detailed Description

The waste heat recovery comprehensive utilization system of the return air shaft in the cold mine area as shown in fig. 1 to 5 comprises a return air shaft 1, an air inlet shaft 7, a waste heat recovery preheating mechanism connected between the return air shaft 1 and the air inlet shaft 7 and a thermoelectric conversion system arranged in the air inlet shaft 7 and matched with the waste heat recovery preheating mechanism, wherein the thermoelectric conversion system is connected with a storage battery 16 and an external power supply 10 through a single-pole double-throw switch 20, a voltage stabilizer 15 is connected between the output end of the thermoelectric conversion system and the storage battery 16, a return air fan 2 is arranged in the return air shaft 1, an air inlet fan 13 and an electric auxiliary heater 11 are arranged in the air inlet shaft 7, and the thermoelectric conversion system is positioned between the electric auxiliary heater 11 and the air inlet fan 13;

the waste heat recovery preheating mechanism comprises a plurality of gravity type heat pipes 5, the thermoelectric conversion system comprises a plurality of semiconductor thermoelectric conversion mechanisms 9 connected in series, the number of the semiconductor thermoelectric conversion mechanisms 9 is equal to that of the gravity type heat pipes 5, the semiconductor thermoelectric conversion mechanisms are in one-to-one correspondence, a heat pipe heat insulation layer 6 is arranged on the outer side of each gravity type heat pipe 5, each gravity type heat pipe 5 comprises an evaporation section 5-1, a condensation section 5-2 and a heat exchange section 5-3, the evaporation section 5-1 is located in an air return shaft 1, the condensation section 5-2 is located in an air inlet shaft 7, and one end of each semiconductor thermoelectric conversion mechanism 9 is attached to the condensation section 5-2;

and a temperature sensor 12 is arranged in the air inlet shaft 7, and the electric auxiliary heater 11, the single-pole double-throw switch 20 and the temperature sensor 12 are all connected with a controller 14.

During the in-service use, form waste heat recovery through combining a plurality of gravity type heat pipes 5 together and preheat the mechanism, and preheat the mechanism with waste heat recovery and combine together with thermoelectric conversion system and carry out the recovery and the utilization of mine return air waste heat, waste heat recovery preheats the low temperature heat energy in the mechanism ability make full use of mine return air and preheats the mine air inlet, thermoelectric conversion system can preheat the residual heat that the mechanism produced with waste heat recovery and carry out thermoelectric generation, and then store the electric energy in battery 16 for subsequent use, whole process need not to adopt extra fuel to carry out the heating of air inlet, resources are saved, green.

It should be noted that, by attaching one end of the semiconductor thermoelectric conversion mechanism 9 to the condensation section 5-2 of the gravity type heat pipe 5, when the heat converted by the gravity type heat pipe 5 is not enough to support the requirement of preheating the intake air, and when the external power supply 10 supplies direct current to the plurality of semiconductor thermoelectric conversion mechanisms 9 connected in series, the semiconductor thermoelectric conversion mechanism 9 can extract the heat attached to one end of the gravity type heat pipe 5 and transfer the heat to the other end, so that the ability of the gravity type heat pipe 5 to absorb the residual heat of the mine return air is enhanced, the heat exchange efficiency of the gravity type heat pipe 5 can be further improved, and the energy utilization rate is improved.

During concrete implementation, through set up electric auxiliary heater 11 in air-supply shaft 7, when the mine return air waste heat of retrieving was not enough preheats the air inlet, accessible electric auxiliary heater 11 assisted the heating to the air inlet, and then avoids owing to preheat the not good low temperature environment that leads to the mine to appear to the air inlet, and then reduces work efficiency.

In practical use, the heat pipe heat insulation layer 6 is arranged on the outer side of the gravity type heat pipe 5, so that energy loss in the heat exchange process of the gravity type heat pipe 5 can be effectively reduced.

During specific implementation, the temperature sensor 12 is arranged in the air inlet shaft 7, so that the temperature in the air inlet shaft 7 can be monitored in real time through the temperature sensor, and further, the phenomenon of supercooling or overheating in the air inlet shaft 7 in the air inlet preheating process is avoided.

In practical use, 7 rows of gravity type heat pipes 5 are arranged, and every two adjacent gravity type heat pipes 5 in each row are separated by 0.4 m.

In this embodiment, a wall of the return air shaft 1 is provided with a return air heat insulation layer 3, and a wall of the intake air shaft 7 is provided with an intake air heat insulation layer 8.

During practical use, the air return heat-insulating layer 3 is arranged on the wall of the air return shaft 1, and the air inlet heat-insulating layer 8 is arranged on the wall of the air inlet shaft 7, so that heat energy loss of mine return air and preheated inlet air can be effectively reduced, and energy overflow in the air flow transportation process is prevented.

In this embodiment, a return air filter screen 4 is arranged in the return air shaft 1, and the return air filter screen 4 is located between the return air fan 2 and the waste heat recovery preheating mechanism.

During the in-service use, through set up return air filter screen 4 in return air shaft 1, can filter the large granule dust of mixing in the mine return air, and then guarantee the life and the operation safety of whole preheating recovery comprehensive utilization system.

In the embodiment, the evaporation section 5-1 is provided with heat exchange fins 5-4, the outer wall of the evaporation section 5-1 is wrapped with heat absorbing materials 5-5, the heat exchange section 5-3 is filled with heat exchange working media, and the heat pipe heat insulation layer 6 is wrapped outside the heat exchange section 5-3.

When the heat exchanger is actually used, the heat exchange fins 5-4 and the heat absorbing material 5-5 are arranged on the evaporation section 5-1, so that the heat exchange efficiency can be effectively improved, and the recovery efficiency of return air waste heat is improved.

It should be noted that the gravity type heat pipe 5 can transfer mass and energy by using a siphon phenomenon, when heat is input to the evaporation section 5-1, the heat exchange working medium of the heat exchange section 5-3 absorbs heat, the temperature rises and changes phase, the steam moves upwards, the energy is released after reaching the condensation section 5-2, and when the steam meets condensation, the condensed heat exchange working medium flows back to the evaporation section 5-1 under the action of gravity, and no external force is required to be applied in the whole circulation process, so that the energy is saved and the efficiency is high.

In the embodiment, the storage battery 16 is connected with a mine lighting device 18 and a mine electrical appliance 19 through an inverter 17;

the controller 14, the storage battery 16 and the inverter 17 are all arranged in a storage utilization control room outside the mine.

In actual use, the inverter 17 can convert direct current in the storage battery 16 into alternating current, so as to supply power to the mine lighting equipment 18 and the mine electrical appliance 19 conveniently.

In this embodiment, the semiconductor thermoelectric conversion mechanism includes a P-type semiconductor 9-1, an N-type semiconductor 9-2 and a metal tie bar 9-3, and the P-type semiconductor 9-1 and the N-type semiconductor 9-2 are connected in series through the metal tie bar 9-3.

In practical use, when a temperature difference exists between two ends of the connection between the P-type semiconductor 9-1 and the N-type semiconductor 9-2, current can be generated, under the action of the voltage stabilizer 15, the stably output electric energy is stored in the storage battery 16, the current generated by one group of P-N semiconductor thermoelectric materials is small, and the P-N semiconductor thermoelectric materials are connected in series to perform thermoelectric power generation; an external power supply 10 is connected to a thermocouple consisting of a P-type semiconductor 9-1 and an N-type semiconductor 9-2, when current flows from a metal diversion strip 9-3 to the N-type semiconductor 9-2 or flows from the P-type semiconductor 9-1 to the metal diversion strip 9-3, heat is released to the outside at a junction to form a hot end, and the other end node continuously absorbs heat from the outside to form a cold end, wherein the heating and cooling functions of the semiconductor thermoelectric conversion mechanism are that heat is extracted from one end of the semiconductor thermoelectric conversion mechanism and is transferred to the other end, so that temperature difference is formed.

In this embodiment, the end of the semiconductor thermoelectric conversion mechanism attached to the condensation section 5-2 is a C-shaped end, and the C-shaped end of the semiconductor thermoelectric conversion mechanism is buckled on the condensation section 5-2 of the plurality of gravity type heat pipes 5.

In practical use, the C-shaped end of the semiconductor thermoelectric conversion mechanism is attached to the condensation section 5-2, so that the gravity type heat pipe 5 is conveniently fastened by the C-shaped end of the semiconductor thermoelectric conversion mechanism, the heat exchange area is increased, and heat extraction from the gravity type heat pipe 5 is facilitated.

The metal flow guide strip 9-3 at one end of the semiconductor thermoelectric conversion mechanism, which is attached to the condensation section 5-2, is a C-shaped end.

In this embodiment, the moving contact of the single-pole double-throw switch 20 is connected to the input terminal of the semiconductor thermoelectric conversion mechanism, the first stationary contact of the single-pole double-throw switch 20 is connected to the battery 16, and the second stationary contact of the single-pole double-throw switch 20 is connected to the external power supply 10.

In actual use, the heat-to-electricity and electricity-to-heat operation of the semiconductor thermoelectric conversion mechanism can be realized by switching the movable contact and the two fixed contacts of the single-pole double-throw switch 20.

Fig. 6 shows a method for recovering and comprehensively utilizing waste heat of a return air shaft in a cold mine area, which comprises the following steps:

step one, mounting a return air filter screen: a return air filter screen 4 is arranged in the return air shaft 1, and the return air filter screen 4 is positioned between the return air fan 2 and the waste heat recovery preheating mechanism;

when the air conditioner is in actual use, the return air fan 2 is immediately started after the return air filter screen 4 is installed.

Step two, filtering mine return air in a return air well: the return air fan 2 pumps mine return air containing a large amount of low-temperature heat energy entering the return air shaft 1 through the connecting roadway to a return air filter screen 4 for filtering, and then the mine return air flows to the waste heat recovery preheating mechanism;

during the in-service use, the return air in the return air shaft 1 all filters through return air filter screen 4 before the waste heat recovery preheats the mechanism, and then can effectively avoid most impurity that mixes in the return air to get into in the waste heat recovery preheats the mechanism.

Step three, recovering waste heat of return air of the mine and preheating the inlet air: as shown in fig. 2, when mine return air filtered by the return air shaft 1 flows through the waste heat recovery preheating mechanism, heat is supplied to the evaporation section 5-1 of the gravity type heat pipe 5, so that a heat exchange working medium in the heat exchange section 5-3 is subjected to phase change and carries a large amount of heat energy to be transferred towards the condensation section 5-2, after the heat exchange working medium subjected to the phase change moves to the condensation section 5-2, the electric auxiliary heater 11 is turned off through the controller 14, the heat of the heat exchange working medium is dissipated through the condensation section 5-2 to preheat inlet air, and meanwhile, the heat exchange working medium is subjected to phase change and returns to the evaporation section 5-1 along the pipe wall of the heat exchange section 5-3 under the action of gravity;

in practical use, the gravity type heat pipe 5 realizes that a heat exchange working medium circularly flows in the gravity type heat pipe 5 by utilizing a siphon principle, the distance between the evaporation section 5-1 and the condensation section 5-2 can reach hundreds of meters to hundreds of meters, and the gravity type heat pipe is suitable for connection between the air inlet shaft 7 and the air return shaft 1, does not need to provide extra circulating power, and is energy-saving and efficient.

It should be noted that when heat is input into the evaporation section 5-1, the heat exchange working medium in the heat exchange section 5-3 absorbs heat, the temperature rises and changes phase, the working medium moves upwards in a steam state, the energy is released after the working medium reaches the condensation section 5-2, the working medium meets the condensation, the condensed heat exchange working medium flows back to the evaporation section 5-1 under the action of gravity, the recovery and utilization of return air waste heat can be continuously carried out, external force is not required to be applied in the whole circulation process, and the energy conservation and the high efficiency are realized.

Step four, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature: monitoring the temperature in the air inlet shaft 7 in real time through a temperature sensor 12, and executing a fifth step when the temperature in the air inlet shaft 7 is higher than the set lowest temperature; when the temperature in the air inlet shaft 7 is less than or equal to the set lowest temperature, executing a sixth step;

in practical use, the temperature in the air inlet shaft 7 is not lower than 2 ℃.

Step five, charging the storage battery by the semiconductor thermoelectric conversion mechanism: the controller 14 controls the single-pole double-throw switch 20 to operate, so that a plurality of semiconductor thermoelectric conversion mechanisms 9 connected in series and the storage battery 16 form a loop, the semiconductor thermoelectric conversion mechanisms 9 generate electromotive force under the action of the seebeck effect, and the electromotive force is stably output under the action of the voltage stabilizer 15 and is stored in the storage battery 16, as shown in fig. 3;

in practical use, the gravity type heat pipe 5 is used for heating mine inlet air, the residual generated heat can be used for the semiconductor thermoelectric conversion mechanism to perform thermoelectric generation, the generated electric energy is stored in the storage battery 16 to supply power to various devices in a mine, and secondary recovery is performed on energy.

The temperature sensor 12 and the voltage regulator 15 are connected in series to a circuit formed by the semiconductor thermoelectric conversion element and the battery 16.

Sixthly, heating the inlet air by the semiconductor thermoelectric conversion mechanism: the controller 14 controls the single-pole double-throw switch 20 to act, so that the semiconductor thermoelectric conversion mechanism and the external power supply 10 form a loop, the peltier effect is utilized to promote the gravity type heat pipe heat exchanger 5 to absorb the residual heat of return air, and the heat is released from one end of the semiconductor thermoelectric conversion mechanism, which is far away from the condensation section 5-2, so as to heat the inlet air in the inlet shaft 7, as shown in fig. 4.

During practical use, the semiconductor thermoelectric conversion mechanism can still be comprehensively utilized except temperature difference power generation, when season conversion is carried out, and the gravity type heat pipe 5 can not meet the requirement for preheating mine inlet air, the external power supply 10 can be arranged, and the Peltier effect of thermoelectric materials is utilized to heat the mine inlet air, so that the purposes of making the best use of things and reducing additional economic expenditure can be achieved.

Step seven, judging whether the air flow temperature in the air inlet well is greater than the set lowest temperature again: when the temperature in the air inlet shaft 7 is higher than the set lowest temperature, returning to the third step; when the temperature in the air inlet shaft 7 is less than or equal to the set lowest temperature, executing the step eight;

step eight, heating the inlet air by an electric auxiliary heater: the electric auxiliary heater 11 is activated by the controller 14 to warm the intake air.

During practical use, when the inlet air of the return air shaft 1 is preheated, the temperature in the return air shaft 1 needs to be monitored in real time through the temperature sensor 12, and supercooling or overheating in the return air shaft 1 is avoided.

The electric auxiliary heater 11 can be powered by the electric energy stored in the battery 16, and the utilization rate of the energy can be effectively improved.

In this embodiment, when the storage battery is charged in the fifth step, the end of the semiconductor thermoelectric conversion mechanism 9 attached to the condensation section 5-2 is heated, and the temperature rises, so that a temperature difference is generated between the end of the semiconductor thermoelectric conversion mechanism 9 attached to the condensation section 5-2 and the other end of the semiconductor thermoelectric conversion mechanism 9 in cold region where the intake air is directly blown, and an electromotive force is generated by the seebeck effect.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.