An absorption refrigeration system for recovering waste heat from shield machine excavation

Abstract

An absorption refrigeration system for recovering waste heat from shield machine excavation includes a high-temperature waste heat circuit, connected between the cutterhead drive device of the shield machine and the equipment requiring heat dissipation, to recover the heat generated by the cutterhead drive device of the shield machine; a medium-temperature waste heat circuit, connected between the hydraulic system of the shield machine and the equipment requiring heat dissipation, to recover the heat within the hydraulic system of the shield machine; and an exhaust gas residual pressure circuit, connected between the exhaust system of the shield machine and the high-temperature waste heat circuit, to convert the exhaust gas into the power required by the high-temperature waste heat circuit. The present invention can recover waste heat for refrigeration, thereby reducing the additional power consumption of the shield machine and reducing carbon emissions. Through the present invention, the temperature of each device of the shield machine is controlled within a specific threshold range to ensure the stable operation of these devices; the absorption refrigeration unit has low maintenance requirements and matches the long-term continuous operation characteristics of the shield machine. The present invention can realize the cascade utilization of waste heat, can effectively recover heat, and solve the problem of large fluctuations in the heat source in the waste heat recovery of the shield machine.

Description

Technical Field

[0001] The invention belongs to the technical field of shield machines, and in particular relates to an absorption refrigeration system for recovering waste heat from shield machine excavation. Background Art

[0002] Key components of a shield machine, including the cutterhead drive, gear transmission system, hydraulic power unit, variable frequency control system, and circulating water module, must maintain operating temperatures within specific thresholds. To ensure thermal stability, a closed water-cooling system is commonly used in engineering practice. This system conducts and exchanges heat through a highly efficient heat dissipation medium, ensuring continuous operation of all components under optimal thermal conditions.

[0003] However, the above method does not effectively and reasonably utilize the heat. Summary of the Invention

[0004] In order to solve the above problems, the present invention further provides an absorption refrigeration system for recovering waste heat from shield machine excavation.

[0005] The technical solution adopted by the present invention is:

[0006] An absorption refrigeration system for recovering waste heat from shield machine excavation, comprising

[0007] The high-temperature waste heat circuit is connected between the cutterhead drive device of the shield machine and the equipment requiring heat dissipation to recover the heat generated by the cutterhead drive device of the shield machine;

[0008] The medium-temperature waste heat circuit is connected between the hydraulic system of the shield machine and the equipment that needs to dissipate heat to recover the heat in the hydraulic system of the shield machine;

[0009] The exhaust gas residual pressure circuit is connected between the exhaust system of the shield machine and the high-temperature waste heat circuit to convert the exhaust gas into the power required by the high-temperature waste heat circuit.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] Energy saving and consumption reduction: Recovering waste heat for refrigeration can reduce the shield machine's additional power consumption and reduce carbon emissions.

[0012] Operation and maintenance costs: The present invention controls the temperature of each device of the shield machine within a specific threshold range, ensuring the stable operation of these devices; the absorption refrigeration unit has low maintenance requirements, which matches the long-term continuous operation characteristics of the shield machine.

[0013] Advantages of working fluid: The refrigerant ammonia solution has a high heat of vaporization and can absorb a large amount of heat during the evaporation process, thereby improving the refrigeration efficiency; the refrigerant lithium bromide solution is non-toxic and non-flammable, meeting the safety requirements of underground projects.

[0014] In addition, the present invention can realize the cascade utilization of waste heat, can effectively recover heat, and solve the problem of large fluctuations in the heat source in the waste heat recovery of the shield machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic structural diagram of the present invention;

[0016] Figure 2 It is a schematic diagram of the heat dissipation fin structure of the present invention;

[0017] Among them: 1. Exhaust system; 2. Exhaust gas residual pressure circuit; 3. Cutter head drive device; 4. High-temperature waste heat circuit; 5. Hydraulic system; 6. Medium-temperature waste heat circuit; 7. Phase change heat storage tank; 8. Equipment requiring heat dissipation; 201. Radial turbine; 401. Heat exchange pipe; 402. First water pump; 403. First switch valve; 404. Air-cooled cooler; 405. Circulating pump; 406. Radiator; 407. First absorption refrigeration unit; 408. Second switch valve; 409. Second water pump; 4011. Heat dissipation fins; 4071. Generator; 4072. First evaporator; 4073. Second evaporator; 601. Heat exchanger; 602. Second absorption refrigeration unit; 603. Third switch valve; 604. Third water pump. DETAILED DESCRIPTION

[0018] In order to better understand the purpose, structure and function of the present invention, the present invention is further described in detail below with reference to the accompanying drawings.

[0019] The driving heat source for ammonia or lithium bromide absorption refrigeration systems is typically hot water or low-pressure steam above 60°C, making them suitable for medium- and low-temperature heat sources such as industrial waste heat and solar energy. Heat generated by friction between the shield machine and soil and other geological structures during tunneling, as well as waste heat generated by the motor (including but not limited to the cutterhead, main drive, reducer, and other areas suitable for heat recovery), typically above 60°C, can serve as a heat source for the absorption chiller. This waste heat can be recovered to produce low-temperature chilled water for equipment cooling or temperature control in monitoring rooms and tunnel environments. Its low vibration and low noise characteristics are highly compatible with the shield machine's operating environment. For example, waste hot water or thermal oil can be introduced into the generator of the absorption chiller to produce chilled water at 5-30°C, which is circulated to the shield machine's cooling system. This can also provide a cooling source for air conditioning in the enclosed tunnel environment, addressing the high temperatures within the shield machine cabin.

[0020] Absorption chillers have flexible requirements for heat source quality (e.g., low-pressure steam, hot water, flue gas, etc.) and are compatible with various types of waste heat removal from shield machines. Absorption chillers can be custom designed as compact modules to fit within the limited space of shield machines.

[0021] Based on the above technology, the present invention provides an absorption refrigeration system for recovering waste heat from shield machine excavation, such as Figure 1 Shown, including

[0022] The high-temperature waste heat circuit 4 (80-150°C) is connected between the cutterhead drive device 3 of the shield machine and the heat dissipation device 8 to recover the heat generated by the cutterhead drive device 3 of the shield machine;

[0023] The medium-temperature waste heat circuit 6 (50-80°C) is connected between the hydraulic system 5 of the shield machine and the device 8 that needs to dissipate heat, and recovers the heat in the hydraulic system 5 of the shield machine;

[0024] The exhaust gas residual pressure circuit 2 is connected between the exhaust system 1 of the shield machine and the high-temperature waste heat circuit 4 to convert the exhaust gas into the power required by the air-cooled cooler 404 of the high-temperature waste heat circuit 4.

[0025] The high-temperature waste heat circuit 4 includes a heat exchange pipe 401, a first water pump 402, a first switch valve 403, an air-cooled cooler 404, a circulating pump 405, a first absorption refrigeration unit 407, a second switch valve 408, a second water pump 409 and a plurality of radiators 406; the heat exchange pipe 401 is arranged in the cutter head drive device 3 of the shield machine, and the two ends of the heat exchange pipe 401 are connected to the generator 4071 of the first absorption refrigeration unit 407, and the heat exchange pipe 401 is installed with a first water pump 402, a first switch valve 403, an air-cooled cooler 404, a circulating pump 405, a first absorption refrigeration unit 407, a second switch valve 408, a second water pump 409 and a plurality of radiators 406; Pump 402 and a first switch valve 403, the first absorption refrigeration unit 407 has two evaporators, the first evaporator 4072 of the first absorption refrigeration unit 407 is connected to the air-cooled cooler 404 through a first circulation pipe, and a circulation pump 405 is provided on the first circulation pipe, the second evaporator 4073 of the first absorption refrigeration unit 407 is connected to multiple radiators 406 through a second circulation pipe, and a second switch valve 408 and a second water pump 409 are provided on the second circulation pipe.

[0026] The heat exchange pipe 401 transfers the heat generated by the air-cooled cooler 404 to the first absorption refrigeration unit 407, and uses the air-cooled cooler 404 and the radiator 406 connected to the first absorption refrigeration unit 407 to dissipate heat, thereby cooling the device 8 requiring heat dissipation.

[0027] like Figure 2 As shown, the outer surface of the tube body of the heat exchange pipe 401 is connected to one end of multiple heat dissipation fins 4011, and the other end of the multiple heat dissipation fins 4011 is in contact with the cutter head drive device 3 of the shield machine, and the other end of the heat dissipation fins 4011 is bent. It can be selected according to actual conditions that the heat exchange pipe 401 is wound around the cutter head drive device 3 of the shield machine and the heat dissipation fins 4011 are in contact with the cutter head drive device 3; or the heat exchange pipe 401 is in contact with the cutter head drive device 3 through the heat dissipation fins 4011, and the heat exchange pipe 401 is not directly in contact with the cutter head drive device 3.

[0028] The heat exchange area can be increased by the heat dissipation fins 4011. The heat dissipation fins 4011 are installed on the pipe body of the heat exchange pipe 401 near the cutter head drive device 3.

[0029] The medium-temperature waste heat circuit 6 includes a heat exchanger 601, a second absorption refrigeration unit 602, a third switch valve 603 and a third water pump 604; the hydraulic system 5 of the shield machine is connected to the hot end inlet and outlet of the heat exchanger 601, and the cold end inlet and outlet of the heat exchanger 601 are connected to the generator of the second absorption refrigeration unit 602. The evaporator of the second absorption refrigeration unit 602 is connected to the radiator 406 through a third circulation pipe, and the third switch valve 603 and the third water pump 604 are provided on the third circulation pipe.

[0030] The heat exchanger 601 exchanges the heat of the hydraulic system 5 to the second absorption refrigeration unit 602, and the second absorption refrigeration unit 602 performs cooling and heat dissipation.

[0031] The plurality of radiators 406 are all installed on the device 8 requiring heat dissipation.

[0032] The exhaust gas residual pressure circuit 2 includes a radial turbine 201, which is coaxially arranged with the fan of the air-cooled cooler 404. The shield machine's exhaust system 1 is connected to the air inlet of the radial turbine 201. Using the shield machine's exhaust gas as power for the air-cooled cooler 404 can save resources.

[0033] The hot end pipe of the heat exchange pipe 401 and the hot end pipe of the third circulation pipe are both installed with a phase change heat storage tank 7, which can buffer the intermittent waste heat fluctuations of the shield machine and ensure the continuous and stable operation of the absorption refrigerator.

[0034] It will be understood that the present invention is described by way of some embodiments, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. An absorption refrigeration system for recovering waste heat from shield machine excavation, characterized by: include A high-temperature waste heat circuit (4) is connected between the cutterhead drive device (3) of the shield machine and the heat dissipation device (8) to recover the heat generated by the cutterhead drive device (3) of the shield machine; A medium-temperature waste heat circuit (6) is connected between the hydraulic system (5) of the shield machine and the heat dissipation device (8) to recover heat in the hydraulic system (5) of the shield machine; The exhaust gas residual pressure circuit (2) is connected between the shield machine's exhaust system (1) and the high-temperature waste heat circuit (4), converting the exhaust gas into the power required by the high-temperature waste heat circuit (4). The high-temperature waste heat circuit (4) includes a heat exchange pipe (401), a first water pump (402), a first switch valve (403), an air-cooled cooler (404), a circulating pump (405), a first absorption refrigeration unit (407), a second switch valve (408), a second water pump (409) and a plurality of radiators (406); the heat exchange pipe (401) is arranged in the cutter head drive device (3) of the shield machine, and both ends of the heat exchange pipe (401) are connected to the generator (4071) of the first absorption refrigeration unit (407), and the heat exchange pipe (401) is connected to the generator (4071) of the first absorption refrigeration unit (407). A first water pump (402) and a first switch valve (403) are installed on the heat pipe (401); a first evaporator (4072) of the first absorption refrigeration unit (407) is connected to the air-cooled cooler (404) through a first circulation pipe, and a circulation pump (405) is provided on the first circulation pipe; a second evaporator (4073) of the first absorption refrigeration unit (407) is connected to a plurality of radiators (406) through a second circulation pipe, and a second switch valve (408) and a second water pump (409) are provided on the second circulation pipe. The medium-temperature waste heat circuit (6) includes a heat exchanger (601), a second absorption refrigeration unit (602), a third switch valve (603) and a third water pump (604); the hydraulic system (5) of the shield machine is connected to the hot end inlet and outlet of the heat exchanger (601), the cold end inlet and outlet of the heat exchanger (601) are connected to the generator of the second absorption refrigeration unit (602), and the evaporator of the second absorption refrigeration unit (602) is connected to the radiator (406) through a third circulation pipeline, and the third switch valve (603) and the third water pump (604) are provided on the third circulation pipeline. The exhaust gas residual pressure circuit (2) includes a radial turbine (201); the radial turbine (201) and a fan of an air-cooled cooler (404) are coaxially arranged, and the exhaust system (1) of the shield machine is connected to the air inlet of the radial turbine (201).

2. The absorption refrigeration system for recovering waste heat from shield machine excavation according to claim 1, characterized in that: The outer surface of the heat exchange pipe (401) is connected to one end of a plurality of heat dissipation fins (4011), and the other ends of the plurality of heat dissipation fins (4011) are in contact with the cutterhead drive device (3) of the shield machine. The other ends of the heat dissipation fins (4011) are bent, and the heat exchange pipe (401) is wound around the cutterhead drive device (3) of the shield machine, while the heat dissipation fins (4011) are in contact with the cutterhead drive device (3); or the heat exchange pipe (401) is in contact with the cutterhead drive device (3) through the heat dissipation fins (4011).

3. The absorption refrigeration system for recovering waste heat from shield machine excavation according to claim 2, characterized in that: The plurality of radiators (406) are all mounted on the device (8) requiring heat dissipation.

4. The absorption refrigeration system for recovering waste heat from shield tunneling according to claim 1, characterized in that: A phase-change heat storage tank (7) is installed on both the hot end pipe of the heat exchange pipe (401) and the hot end pipe of the third circulation pipe.

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