Mine ventilation air methane recovery system

Abstract

The utility model belongs to mine ventilation and energy -conserving technical field discloses a kind of mine ventilation air heat recovery system, including the heat recovery unit of connection ventilation air and fresh air air path, its inside is equipped with heat exchanger group, and heat recovery unit is equipped with the airflow distribution device that can be left and right reversed at fresh air air inlet, the device periodically alternately sends fresh air into the left and right two parts of heat exchanger group.When a part carries out heat exchange, another part is only passed by warm ventilation air, and online defrosting is carried out using ventilation air waste heat, so as to effectively prevent ice blockage.The utility model can also generate electricity using ventilation air kinetic energy, and power supply for the compensation heating device of air supply pipeline.The system realizes efficient online anti-frost function through ingenious structure design, and the structure is simple, reliable in operation, and suitable for severe cold mining area.

Description

Technical Field

[0001] This utility model relates to a mine exhaust air heat recovery system, belonging to the field of mine ventilation and energy-saving technology. Background Technology

[0002] In mines in the cold regions of northern my country, the temperature of the fresh air entering the mine during winter is extremely low. It must be heated to meet the requirement of a shaft ventilation temperature of more than 2°C as stipulated in the "Coal Mine Safety Regulations" to prevent the shaft from freezing and ensure production safety.

[0003] Traditional heating methods mostly use gas-fired boilers or electric heating, which consume a lot of energy and have high operating costs. To save energy and reduce emissions, utilizing the exhaust air from mines, which contains abundant heat energy, to heat fresh air has become an important direction for technological development. Among these technologies, direct heat exchange technologies such as plate-fin heat exchangers have attracted much attention due to their simple structure and high heat exchange efficiency.

[0004] However, existing direct heat exchange systems face a common and serious technical challenge in frigid environments: when cold fresh air flows through the heat exchanger in winter, water vapor in the fresh air duct frosts, severely reducing heat exchange efficiency and clogging the duct, leading to insufficient fresh air volume and threatening underground safety. Solving this problem typically requires an additional, complex defrosting system, which increases costs and energy consumption and affects the continuity and stability of heat recovery.

[0005] Therefore, the market urgently needs a mine exhaust air heat recovery system that is simple in structure, reliable in operation, and can effectively solve its own frost problem. Utility Model Content

[0006] The purpose of this invention is to overcome the above-mentioned defects of the prior art and provide a mine exhaust air heat recovery system that can effectively prevent frost and blockage through its own operating mode.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A mine exhaust air heat recovery system includes an exhaust air outlet shaft and a fresh air inlet shaft. The exhaust air outlet shaft is connected to an exhaust duct, which is equipped with a main exhaust fan. The fresh air inlet shaft is connected to a supply air duct, which is equipped with a supply fan. The exhaust air duct and the supply air duct are connected by a heat recovery unit, which transfers heat from the exhaust air to the fresh air to increase the temperature of the fresh air entering the mine.

[0008] The heat recovery unit is equipped with a heat exchanger group, which includes multiple plate-fin heat exchange units arranged in a horizontal array. Each plate-fin heat exchange unit includes several alternating horizontal fresh air ducts and vertical exhaust air ducts. The media (fresh air and exhaust air) in the horizontal fresh air ducts and the vertical exhaust air ducts do not come into contact with each other.

[0009] The heat recovery unit is equipped with a reversible airflow distribution device at the fresh air inlet. This airflow distribution device can periodically and alternately distribute the incoming fresh air to the left and right parts of the heat exchanger unit.

[0010] In a preferred embodiment, the air supply duct is divided into an above-ground air supply section and an underground air supply section. The above-ground air supply section is connected to the heat recovery unit, and the underground air supply section is connected to the fresh air intake shaft, utilizing the insulation properties of the soil to reduce heat loss.

[0011] As a further preferred embodiment, the ground-level air supply section is provided with a jacket, and a coiled electric heating wire is provided inside the jacket for compensating heating of the fresh air during the delivery process.

[0012] Furthermore, to achieve energy self-sufficiency, the exhaust air outlet at the top of the heat recovery unit is designed as a cone shape to collect airflow, and a wind-powered generator is installed at the outlet. The wind-powered generator is equipped with an energy storage device, which powers the coiled heating wire.

[0013] In addition, to adapt to the operational needs of different seasons, the exhaust duct is equipped with a duct conversion device, which can bypass the heat recovery unit during the non-heating season and allow the exhaust air to be directly discharged into the atmosphere.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. Ingenious Structure for Online Frost Prevention: The core innovation of this invention lies in its airflow distribution device. By periodically alternating the operation of the left and right sections of the heat exchanger assembly, a "heat exchange-regeneration" cycle is achieved. When one section is ventilated with fresh air for heat exchange, the other section suspends fresh air intake, allowing only warm exhaust air to continuously pass through. The residual heat of this exhaust air is sufficient to melt any trace frost crystals that may have formed in the previous cycle and to allow the heat exchanger to "warm up," thereby effectively preventing the accumulation and blockage of ice layers and ensuring the long-term stable operation of the system.

[0015] 2. Energy-efficient and efficient, requiring no additional defrosting energy consumption: The defrosting process is completed using the residual heat of the exhaust air itself, eliminating the need for additional electric heating or hot air bypass defrosting equipment as required by traditional technologies, thus avoiding additional energy consumption and truly achieving energy saving.

[0016] 3. Comprehensive energy utilization for further energy saving: By installing a wind turbine generator at the exhaust air outlet, the kinetic energy of the exhaust air is captured and converted into electrical energy for compensating heating of the air supply duct, realizing the cascade utilization of energy and improving the overall energy-saving efficiency of the system.

[0017] 4. Simplified system and high reliability: Compared with complex heat pump systems or systems with independent defrosting modules, this utility model has a simpler structure, fewer moving parts, and clearer control logic, thereby improving operational reliability and reducing maintenance costs. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the elevation structure of this utility model; Figure 2 This is a schematic diagram of the planar structure of this utility model; Figure 3 This is a schematic diagram of a heat exchanger assembly consisting of multiple horizontally arrayed plate-fin heat exchange units.

[0019] In the diagram: 1. Exhaust air outlet shaft; 2. Main exhaust fan; 3. Duct conversion device; 4. Exhaust duct; 5. Fresh air inlet; 6. Airflow distribution device; 7. Wind-powered generator; 8. Energy storage device; 9. Heat recovery unit; 10. Above-ground air supply section; 11. Coiled heating wire; 12. Air supply fan; 13. Underground air supply section; 14. Fresh air inlet shaft; 15. Heat exchanger assembly. Detailed Implementation

[0020] The present invention will be further described below with reference to specific embodiments.

[0021] The description of this utility model is merely a structural or even functional description of the embodiments, and the scope of this utility model is not limited by the embodiments described herein.

[0022] like Figures 1-3 As shown, this embodiment is achieved through the following technical solution: A mine exhaust air heat recovery system includes an exhaust air outlet shaft 1 and a fresh air inlet shaft 14. The exhaust air outlet shaft 1 is connected to an exhaust duct 4, and an exhaust main fan 2 is installed on the exhaust duct 4. The fresh air inlet shaft 14 is connected to an air supply duct, and an air supply fan 12 is installed on the air supply duct. The exhaust duct 4 and the air supply duct are connected through a heat recovery unit 9, which transfers the heat in the exhaust air to the fresh air to increase the temperature of the fresh air entering the mine.

[0023] The heat recovery unit 9 is equipped with a heat exchanger group 15, which includes multiple plate-fin heat exchange units arranged in a horizontal array. Each plate-fin heat exchange unit includes several alternating horizontal fresh air ducts and vertical exhaust air ducts. The media in the horizontal fresh air ducts and the vertical exhaust air ducts do not come into contact with each other. In addition, the fresh air inlet 5 of the heat recovery unit 9 is equipped with an airflow distribution device 6 that can switch left and right directions, which can alternately distribute the incoming fresh air to the left and right parts of the heat exchanger group 15.

[0024] The air supply duct is divided into an above-ground air supply section 10 and an underground air supply section 13. The above-ground air supply section 10 is connected to the heat recovery unit 9, and the underground air supply section 13 is connected to the fresh air intake shaft 14. The underground air supply section 13 utilizes the heat insulation properties of the soil to reduce heat loss. The above-ground air supply section 10 is equipped with a jacket, and a coiled electric heating wire 11 is installed inside the jacket.

[0025] The exhaust air outlet at the top of the heat recovery unit 9 is conical, and a wind-driven generator 7 is installed at the outlet. The wind-driven generator 7 is equipped with an energy storage device 8, which is used to supply power to the coiled heating wire 11.

[0026] The exhaust duct 4 is equipped with a duct conversion device 3, which can shut off the exhaust duct 4 and discharge the exhaust air into the atmosphere.

[0027] During winter operation, exhaust air is drawn out from exhaust air outlet shaft 1 via main exhaust fan 2, guided into exhaust duct 4 through duct conversion device 3, and enters heat recovery unit 9 from the bottom. Inside heat recovery unit 9, exhaust air flows from bottom to top through the longitudinal exhaust air duct of heat exchanger group 15, transferring its heat to fresh air before being discharged from the top of the unit.

[0028] Meanwhile, cold outdoor fresh air is drawn in through the fresh air inlet 5 and first passes through the airflow distribution device 6. In this embodiment, the airflow distribution device 6 can be wind-driven, operating on the same principle as the self-rotating guide vanes of a fan. It is driven to rotate by the fresh air flow and can alternately distribute the incoming fresh air to the left and right parts (A, B) of the heat exchanger group 15. Of course, other electrically driven methods can also be used for active air distribution, such as a rotary valve or a set of linked louvers.

[0029] When the left half is exchanging heat, its heat exchange surface temperature drops due to the cold fresh air, potentially causing slight frost buildup. Meanwhile, the right half, without any fresh air intake, receives only exhaust air at approximately 10-20°C. The residual heat of this exhaust air quickly melts the frost on its surface, raising its overall temperature and completing the "defrosting and regeneration" process. When the fresh air switches to the right half in the next cycle, it is already in a warm, frost-free optimal heat exchange state. Through this cycle, the entire heat exchanger assembly 15 can operate continuously and efficiently without freezing or clogging.

[0030] The heated fresh air flows out from the heat recovery unit 9 and enters the air supply duct. To compensate for the heat loss caused by the temperature difference between the fresh air supply section 10 above ground and the outside, the coiled heating wire 11 inside its outer jacket can be activated for heating. The energy for this heating wire preferably comes from the wind-driven generator 7 installed at the exhaust air outlet at the top of the heat recovery unit 9. This generator uses the kinetic energy of the exhaust air to generate electricity, which is then stably output through the energy storage device 8. Finally, the fresh air is pressurized by the air supply fan 12 and sent into the fresh air intake shaft 14 through the underground air supply section 13, which has a natural heat insulation effect.

[0031] During the non-heating season, the air duct conversion device 3 can be switched to allow exhaust air to be directly discharged into the atmosphere through the exhaust duct, and the heat recovery system will stop operating.

[0032] Of course, the above description is only a preferred embodiment of this utility model and should not be considered as limiting the scope of the embodiments of this utility model. This utility model is not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of this utility model should be included in the patent coverage of this utility model.

Claims

1. A mine exhaust air heat recovery system, comprising an exhaust air outlet shaft (1) and a fresh air intake shaft (14), wherein the exhaust air outlet shaft (1) is connected to an exhaust duct (4), the exhaust duct (4) is equipped with an exhaust main fan (2), and the fresh air intake shaft (14) is connected to an air supply duct, the air supply duct is equipped with an air supply fan (12), characterized in that, The exhaust duct (4) is connected to the air supply duct through the heat recovery unit (9). The heat recovery unit (9) transfers the heat in the exhaust air to the fresh air to increase the temperature of the fresh air entering the mine. The heat recovery unit (9) is equipped with a heat exchanger group (15). The heat exchanger group (15) includes multiple plate-fin heat exchange units arranged in a horizontal array. Each plate-fin heat exchange unit includes several alternating horizontal fresh air ducts and vertical exhaust air ducts. The media in the horizontal fresh air ducts and the vertical exhaust air ducts do not come into contact with each other. The heat recovery unit (9) is equipped with a left-right reversible airflow distribution device (6) at the fresh air inlet (5), which can alternately distribute the incoming fresh air to the left and right parts of the heat exchanger group (15).

2. The mine exhaust air heat recovery system according to claim 1, characterized in that, The air supply duct is divided into an above-ground air supply section (10) and an underground air supply section (13). The above-ground air supply section (10) is connected to the heat recovery unit (9), and the underground air supply section (13) is connected to the fresh air intake shaft (14).

3. The mine exhaust air heat recovery system according to claim 2, characterized in that, The ground air supply section (10) is equipped with a jacket, and a coiled electric heating wire (11) is installed inside the jacket.

4. The mine exhaust air heat recovery system according to claim 3, characterized in that, The exhaust air outlet at the top of the heat recovery unit (9) is conical, and a wind-powered generator (7) is installed at the outlet. The wind-powered generator (7) is equipped with an energy storage device (8), which is used to supply power to the coiled heating wire (11).

5. The mine exhaust air heat recovery system according to claim 1, characterized in that, The exhaust duct (4) is equipped with a duct conversion device (3), which can shut off the exhaust duct (4) and discharge the exhaust air into the atmosphere.

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