Two-stage heat pump drying system and method for hydrogen-driven coupling rotary wheel dehumidification

Abstract

The invention discloses a two-stage heat pump drying system and method for hydrogen-driven coupling rotary wheel dehumidification. A hydrogen fuel supply system of the two-stage heat pump drying system comprises an upstream hydrogen fuel system and a downstream hydrogen fuel system. The hydrogen engine driving system comprises a hydrogen engine, a belt pulley, a coupler, a gearbox, a water pump and a flue gas heat exchanger. The two-stage compression heat pump system comprises a low-pressure-stage compressor, a high-pressure-stage compressor, an intercooler, a liquid storage device, an auxiliary condenser, a main condenser, an evaporator, a throttling valve, a one-way valve and an electronic expansion valve. The rotating wheel dehumidification system comprises a dehumidification rotating wheel, a total heat exchanger, a regeneration fan, a dehumidification fan and a drying box. The system is stable and efficient in operation, full utilization of waste heat is achieved, the energy utilization rate is increased, energy conservation and emission reduction are achieved, power consumption is reduced, and the service life is prolonged. Independent temperature and humidity control can be achieved, the heating efficiency and the drying rate in a low-temperature environment are improved, the dew point temperature of dehumidified air is increased, and the drying effect is improved.

Description

Technical Field

[0001] The invention relates to a two-stage heat pump drying system and method for hydrogen-driven coupled rotary dehumidification, belonging to the technical field of heat pump drying. Background Art

[0002] Drying technology is widely used in industry, agriculture and other fields. As the country with the highest output of fruits, vegetables and aquatic products in the world, drying technology is a necessary processing link in China. However, the drying process consumes a lot of energy. Therefore, in order to meet the requirements of energy-saving, high-efficiency, green and safe, low-carbon and high-quality products, it is urgent to develop new and efficient combined drying technology. my country's traditional drying technology is relatively backward, with low drying quality and high energy consumption.

[0003] The currently commonly used heat pump drying technology still has shortcomings in drying and dehumidification.

[0004] First, the heat pump drying temperature is low, generally below 50°C. If a higher drying temperature is provided, the temperature difference between the condensing temperature and the evaporating temperature will be larger, resulting in a high compression ratio, a rapid decrease in the volumetric efficiency of the compressor, a rapid decrease in the heating capacity, a significant increase in the power consumption of the compressor, and an increase in the exhaust temperature, which will accelerate the wear of the internal mechanical parts of the compressor and shorten the service life of the compressor.

[0005] Second, the heat pump drying commonly used at present is mostly based on single-stage vapor compression refrigeration, and the drying temperature that can be obtained is relatively low, which leads to a too long drying process and easily causes deterioration of heat-sensitive materials.

[0006] Third, the performance of a single-stage compression heat pump is extremely sensitive to ambient temperature, especially in low-temperature environments. The drop in evaporation temperature causes a decrease in the compressor's air intake, significantly reducing the system's heating efficiency and affecting the drying effect.

[0007] Fourth, the energy-saving effect of heat pump dehumidification and drying is obvious. The air is cooled by the evaporator for dehumidification, but the air temperature coming out of the drying box is relatively high. After passing through the evaporator, the temperature reduction is limited, resulting in unsatisfactory dehumidification effect. The dew point temperature is high after dehumidification, and the water vapor partial pressure of the dry air is high, which makes the drying driving force - water vapor pressure difference low, which will further affect the dehumidification effect of the dry air and further reduce the drying rate of the heat pump drying.

[0008] Fifth, the rotary dehumidification absorbs the moisture in the humid air through the adsorption material in the rotary wheel, and the regenerated air is regenerated through the regeneration area of ​​the rotary wheel, which has a good dehumidification effect. However, the regenerated air temperature is higher and the heat required is larger, resulting in higher energy consumption. Summary of the invention

[0009] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and thus propose a two-stage heat pump drying system and method for hydrogen-driven coupled rotary dehumidification.

[0010] The technical solution provided by the present invention is as follows: a two-stage heat pump drying system driven by hydrogen and coupled with a rotary dehumidification, characterized in that it comprises a hydrogen fuel supply system, a hydrogen engine drive system, a two-stage compression heat pump system and a rotary dehumidification system; The hydrogen fuel supply system comprises an upstream hydrogen fuel system and a downstream hydrogen fuel system; the upstream hydrogen fuel system comprises a plurality of first hydrogen cylinders connected in parallel, each of the first hydrogen cylinders is connected to a pressure regulator via a switch valve, the pressure regulator is connected to an inlet of a hydrogen filter via a first emergency shut-off valve, the outlet of the hydrogen filter is connected to an inlet of a mass flow meter via a first pressure sensor, the second hydrogen cylinder is connected to the first pressure sensor via a second switch valve and a third switch valve, the outlet of the mass flow meter is connected to a hydrogen inlet of a hydrogen mixer via a second pressure sensor, the hydrogen mixer is arranged below an inlet of a flame arrester, the outlet of the flame arrester is connected to a hydrogen engine via a second emergency shut-off valve, and the flame arrester is connected to a pressure release valve; The hydrogen engine driving system comprises a hydrogen engine, wherein the hydrogen engine is connected to a second pulley and a third pulley via a first pulley, the second pulley is connected to a high-pressure compressor of a two-stage compression heat pump system via a first coupling and a first gearbox; the third pulley is connected to a low-pressure compressor of the two-stage compression heat pump system via a second coupling and a second gearbox; the first outlet of the hydrogen engine is connected to a first inlet of a second heat exchanger via a first water pump, and the first outlet of the second heat exchanger is connected to an inlet of the hydrogen engine; the second outlet of the hydrogen engine is connected to a first inlet of a flue gas heater, the first outlet of the flue gas heat exchanger outputs flue gas to the outside, the second outlet of the flue gas heater is connected to a first inlet of a first heat exchanger via a second water pump, and the first outlet of the first heat exchanger is connected to a second inlet of the flue gas heat exchanger; The two-stage compression heat pump system includes a low-pressure compressor, a refrigerant outlet of the low-pressure compressor is connected to the refrigerant inlet of the high-pressure compressor through a third one-way valve, the refrigerant outlet of the high-pressure compressor is connected to the inlet of the main condenser through the second electronic expansion valve in one way, and is connected to the inlet of the auxiliary condenser through the first electronic expansion valve in another way, the outlet of the auxiliary condenser is connected to the inlet of the main condenser through the third electronic expansion valve in one way, and is connected to the liquid inlet of the liquid reservoir through the first one-way valve and the fourth electronic expansion valve in another way; the outlet of the main condenser is connected to the liquid inlet of the liquid reservoir through the second one-way valve; the liquid outlet of the liquid reservoir is connected to the first liquid inlet of the intercooler through a pipeline in one way, and is connected to the second liquid inlet of the intercooler through the first throttle valve in another way, the air outlet of the intercooler is connected to the air inlet of the high-pressure compressor, the liquid outlet of the intercooler is connected to the liquid inlet of the evaporator through the second throttle valve, and the air outlet of the evaporator is connected to the air inlet of the low-pressure compressor; The rotary dehumidification system includes a dehumidification wheel, a dehumidification outlet of the dehumidification wheel is connected to the first air inlet of the total heat exchanger through an air duct, the first air outlet of the total heat exchanger is connected to the air inlet of the main condenser through the air duct, the air outlet of the main condenser is connected to the air inlet of the drying box, the air outlet of the drying box is connected to the air inlet of the evaporator through the air duct, the air outlet of the evaporator is connected to the dehumidification fan through the air duct, and the dehumidification fan is connected to the dehumidification inlet of the dehumidification wheel through the air duct; the air outlet of the auxiliary condenser is connected to the second inlet of the second heat exchanger through the air duct, the second outlet of the second heat exchanger is connected to the second inlet of the first heat exchanger through the air duct, the second outlet of the first heat exchanger is connected to the regeneration fan through the air duct, the regeneration fan is connected to the regeneration inlet of the dehumidification wheel through the air duct, the regeneration outlet of the dehumidification wheel is connected to the second air inlet of the total heat exchanger through the air duct, and the second air outlet of the total heat exchanger is connected to the outside.

[0011] Furthermore, the hydrogen mixer is 15.25 cm away from the inlet of the flame arrester.

[0012] A two-stage heat pump drying method driven by hydrogen and coupled with a rotary dehumidification, characterized in that it specifically comprises: The high-pressure hydrogen in the first hydrogen cylinder enters the hydrogen filter through the pressure regulator, and the hydrogen filter filters out other impurities in the hydrogen. The filtered hydrogen enters the mass flow meter, enters the hydrogen mixer and mixes with air, and the mixed gas enters the hydrogen engine through the flame arrester; the supply of high-pressure hydrogen in the first hydrogen cylinder is controlled by adjusting the opening of the first switch valve; when an emergency occurs, the first emergency shut-off valve is closed to stop the supply of high-pressure hydrogen; the pressure of the high-pressure hydrogen entering the system is adjusted by the pressure regulator; the hydrogen entering the hydrogen engine is measured by the mass flow meter; The second switch valve and the third switch valve are opened, and the first switch valve is closed. The hydrogen remaining in the system slowly flows into the second hydrogen cylinder through the second switch valve and the third switch valve; the pressure and flow of the hydrogen flowing into the second hydrogen cylinder are monitored by the first pressure sensor and the mass flow meter; the collected hydrogen is stored in the second hydrogen cylinder, and at this time, the second switch valve and the third switch valve are opened, and the first switch valve is opened, and the hydrogen in the second hydrogen cylinder and the hydrogen filtered by the hydrogen filter are mixed into the mass flow meter to continue to provide hydrogen for the hydrogen fuel supply system; The hydrogen engine drives the first pulley to rotate, thereby driving the second pulley and the third pulley to rotate, and through the rotation of the pulley, drives the first coupling and the second coupling to operate, further drives the first gearbox and the second gearbox to operate, and drives the high-pressure compressor and the low-pressure compressor to operate; the flue gas discharged by the hydrogen engine recovers the heat of the flue gas through the flue gas heat exchanger, exchanges heat with cooling water, heats the cooling water, and discharges the heat-released flue gas to the outside; the cooling water after heat exchange with the flue gas exchanges heat with the regeneration air through the second water pump and the first heat exchanger, and heats the regeneration air; the waste heat generated by the hydrogen engine exchanges heat with the cooling water, and the cooling water then exchanges heat with the regeneration air through the first water pump and the second heat exchanger, and the regeneration air is heated by the first heat exchanger and the second heat exchanger; The high-pressure liquid coming out of the main condenser first enters the liquid storage tank for storage, and then is divided into two paths. One path passes through the intercooler and the first throttle valve to reduce its pressure to the intermediate pressure and evaporate in the intercooler; the other part flows through the intercooler in the coil, exchanges heat with the refrigerant vapor evaporated at the intermediate pressure outside the tube through the coil, and then evaporates and refrigerates in the evaporator; the saturated refrigerant vapor coming out of the evaporator is sucked in by the low-pressure compressor and compressed to the intermediate pressure, and then discharged to the high-pressure compressor, mixed with the saturated vapor coming out of the intercooler, and then enters the high-pressure compressor to be compressed to the condensation pressure, condensed into high-pressure liquid in the main condenser, and then circulated again; The operation of the rotary dehumidifier includes two processes: dehumidification and regeneration. During the dehumidification process, humid air enters the dehumidification area of ​​the rotary wheel, where the water vapor is adsorbed by the desiccant and the air becomes dry. As the rotary wheel rotates, it enters the regeneration area, where the desiccant is desorbed by heating the regenerated air to restore its moisture absorption capacity. The regenerated air loses sensible heat during the desorption process and becomes humid air and is discharged outdoors, completing the moisture transfer. After the dry air dries the material in the drying room, it passes through the evaporator for heat exchange, releases heat to reduce the temperature, and the air with reduced temperature enters the dehumidification zone of the dehumidification wheel for dehumidification under the action of the dehumidification fan. The dehumidified dry air passes through the total heat exchanger and the main condenser for heat exchange to increase the air temperature, forming high-temperature dry air and then enters the drying room to dry the material; under the action of the regeneration fan, the regenerated air first passes through the auxiliary condenser for heat exchange to increase the regeneration temperature, and then passes through the second heat exchanger and the first heat exchanger in turn for heat exchange to further increase the regeneration temperature, and then enters the regeneration zone of the dehumidification wheel. The regenerated air can enter the total heat exchanger to exchange heat with the dehumidified air and recycle the heat; by adjusting the opening of the first electronic expansion valve, the refrigerant flow entering the auxiliary condenser is controlled, and the temperature of the regeneration air can be controlled by heat exchange with the regeneration air. By adjusting the switches of the third electronic expansion valve and the fourth electronic expansion valve, the series and parallel connection of the main condenser and the auxiliary condenser can be realized.

[0013] The beneficial effects of the present invention are as follows: hydrogen energy is a new energy source that is not dependent on fossil fuels and has abundant reserves. Compared with petroleum fuels, hydrogen has better combustion performance and faster flame propagation speed, which is conducive to improving combustion efficiency. Using a hydrogen engine to drive a heat pump compressor can realize a heat pump cycle, and the flue gas and cylinder jacket cooling water emitted by the hydrogen engine combustion contain a large amount of waste heat resources. If the waste heat is recovered and then heated to regenerate the rotary dehumidifier, the humidity of the drying air can be reduced, which can improve the overall drying efficiency. Compared with an electric heat pump, its primary energy utilization rate is higher.

[0014] The invention drives the pulley to rotate by the work of the hydrogen engine, and then drives the coupling and the gearbox, thereby driving the low-pressure compressor and the high-pressure compressor to work. A two-stage compression heat pump cycle is realized, and the waste heat of the hydrogen engine is used for the regeneration air heating of the rotary dehumidification, combined with the two-stage waste heat recovery of the total heat exchanger, to achieve heat pump drying with higher temperature and lower humidity.

[0015] First, the present invention adopts a hydrogen engine, a pulley, a coupling, a gearbox, and a flue gas heat exchanger. The hydrogen engine works to drive the low-pressure compressor and the high-pressure compressor, thereby driving the entire two-stage compression heat pump system to operate, and the high-pressure and low-pressure compressors are coordinated and efficiently operated through the coupling and gearbox.

[0016] Second, through heat exchangers and other components, two-stage high- and low-grade waste heat recovery is achieved, that is, through flue gas heat exchangers, water pumps, heat exchangers and other components, high-grade waste heat recovery of flue gas and cylinder cooling water is achieved, and low-grade waste heat recovery of dry air is achieved through full heat heat exchangers. Through flue gas heat exchangers and heat exchangers and other components, heat exchange with regeneration air is achieved, the regeneration temperature of regeneration air is increased, and the waste heat is fully utilized, the energy utilization rate is improved, and the effect of energy saving and emission reduction is achieved.

[0017] Third, the present invention realizes a two-stage compression heat pump cycle through a low-pressure compressor, a high-pressure compressor, a main condenser, an auxiliary condenser, an intermediate cooler, a liquid storage device, a throttle valve, an evaporator and an electronic expansion valve. The main condenser and the auxiliary condenser can also be connected in series and in parallel through the electronic expansion valve, the main condenser, the auxiliary condenser and the auxiliary valve. While ensuring the stable operation of the system, the problem of excessive temperature difference between the condensing temperature and the evaporating temperature is solved, the power consumption of the compressor is reduced, and the service life of the compressor is extended.

[0018] Fourth, the present invention couples the rotary dehumidification and drying system and the two-stage compression heat pump system to achieve independent control of temperature and humidity, improve the heating efficiency of the system in a low-temperature environment, increase the dew point temperature of the air after dehumidification, improve the drying effect, and increase the drying rate of the system in a low-temperature environment to meet the drying needs of the system in a low-temperature environment.

[0019] Fifth, the present invention recycles waste heat from engine exhaust. Depending on the operating conditions, the exhaust temperature of a hydrogen engine can reach 200-500°C. By heating this exhaust to above 450°C and directly providing heat to the reaction system, the stability of the heat source is ensured, and the heat in the engine exhaust is fully utilized, thereby improving the overall energy utilization rate of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 is a regional diagram of the dehumidification wheel of the present invention; In the figure: 1, low-pressure compressor, 2, high-pressure compressor, 3, intercooler, 4, liquid storage tank, 5, first non-return valve, 6, auxiliary condenser, 7, main condenser, 8, second non-return valve, 9, first throttle valve, 10, regeneration fan, 11, evaporator, 12, dehumidification fan, 13, dehumidification wheel, 14, total heat exchanger, 15, drying box, 16, first electronic expansion valve, 17, second electronic expansion valve, 18, third electronic expansion valve, 19, second throttle valve, 20, fourth electronic expansion valve, 21, third non-return valve, 22, hydrogen engine, 23, first pulley, 24, second pulley, 25, first coupling, 2 6. First gearbox, 27. Third pulley, 28. Second gearbox, 29. Second coupling, 30. First water pump, 31. Second water pump, 32. Flue gas heat exchanger, 33. First heat exchanger, 34. Second heat exchanger, 35. Second emergency shut-off valve, 36. Pressure release valve, 37. Flame arrester, 38. Hydrogen mixer, 39. First pressure sensor, 40. Second pressure sensor, 41. First switch valve, 42. Hydrogen filter, 43. Second switch valve, 44. First hydrogen cylinder, 45. Third switch valve, 46. Pressure regulator, 47. First emergency shut-off valve, 48. Second hydrogen cylinder, 49. Mass flow meter. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is described in detail below with reference to the accompanying drawings: like Figure 1 As shown, a hydrogen-driven two-stage heat pump drying system coupled with a rotary dehumidification system includes a hydrogen fuel supply system, a hydrogen engine drive system, a two-stage compression heat pump system and a rotary dehumidification system.

[0022] The hydrogen fuel supply system includes two subsystems, namely, an upstream hydrogen fuel system and a downstream hydrogen fuel system. The upstream hydrogen fuel system includes a hydrogen mixer 38, a first pressure sensor 39, a second pressure sensor 40, a first switch valve 41, a hydrogen filter 42, a second switch valve 43, a first hydrogen bottle 44, a third switch valve 45, a pressure regulator 46, a first emergency shut-off valve 47 and a mass flow meter 49; the downstream hydrogen fuel system includes a second emergency shut-off valve 35, a pressure release valve 36 and a flame arrester 37. The first hydrogen bottle 44 is used to store hydrogen and provide sufficient hydrogen for the hydrogen fuel supply system. Several (5 in this embodiment) first hydrogen bottles 44 are connected in parallel, each of which is connected to a pressure regulator 46 through a switch valve 41, and the pressure regulator 46 is connected to the inlet of the hydrogen filter 42 through the first emergency shut-off valve 47, and the outlet of the hydrogen filter 42 is connected to the inlet of the mass flow meter 49 through the first pressure sensor 39. The second hydrogen cylinder 48 is connected to the first pressure sensor 39 through the second switch valve 43 and the third switch valve 45. The outlet of the mass flow meter 49 is connected to the hydrogen inlet of the hydrogen mixer 38 through the second pressure sensor 40. The hydrogen mixer 38 is installed below the inlet of the flame arrester 37, 15.25 cm away from the inlet of the flame arrester 37. The outlet of the flame arrester 37 is connected to the hydrogen engine 22 through the second emergency shut-off valve 35. The flame arrester 37 is connected to the pressure release valve 36.

[0023] The hydrogen engine driving system includes a hydrogen engine 22, a first pulley 23, a second pulley 24, a first coupling 25, a first gearbox 26, a third pulley 27, a second gearbox 28, a second coupling 29, a first water pump 30, a second water pump 31, a flue gas heat exchanger 32, a first heat exchanger 33, and a second heat exchanger 34. The output end of the hydrogen engine 22 is connected to the first pulley 23, the first pulley 23 is connected to the second pulley 24 and the third pulley 27 through shafts, the other end of the second pulley 24 is connected to the first coupling 25 through a shaft, the first coupling 25 is connected to the first gearbox 26 through a shaft, and the first gearbox 26 is connected to the high-pressure compressor 2; the other end of the third pulley 27 is connected to the second coupling 29 through a shaft, the second coupling 29 is connected to the second gearbox 28 through a shaft, and the other end of the second gearbox 28 is connected to the low-pressure compressor 1 through a shaft. The first outlet of the hydrogen engine 22 is connected to the first inlet of the second heat exchanger 34 through the first water pump 30, and the first outlet of the second heat exchanger 34 is connected to the inlet of the hydrogen engine 22. The second outlet of the hydrogen engine 22 is connected to the first inlet of the flue gas heater 32, and the first outlet of the flue gas heat exchanger 32 outputs flue gas to the outside. The second outlet of the flue gas heater 32 is connected to the first inlet of the first heat exchanger 33 through the second water pump 31, and the first outlet of the first heat exchanger 33 is connected to the second inlet of the flue gas heat exchanger 32.

[0024] The two-stage compression heat pump system comprises a low-pressure compressor 1, a high-pressure compressor 2, an intercooler 3, a liquid storage tank 4, a first one-way valve 5, an auxiliary condenser 6, a main condenser 7, a second one-way valve 8, a first throttle valve 9, an evaporator 11, a first electronic expansion valve 16, a second electronic expansion valve 17, a third electronic expansion valve 18, a second throttle valve 19, a fourth electronic expansion valve 20, and a third one-way valve 21. The refrigerant outlet of the low-pressure compressor 1 is connected to the refrigerant inlet of the high-pressure compressor 2 through the third one-way valve 21, the refrigerant outlet of the high-pressure compressor 2 is connected to the inlet of the main condenser 7 through the second electronic expansion valve 17, and is connected to the inlet of the auxiliary condenser 6 through the first electronic expansion valve 16. The outlet of the auxiliary condenser 6 is connected to the inlet of the main condenser 7 through the third electronic expansion valve 18, and is connected to the liquid inlet of the liquid storage tank 4 through the first one-way valve 5 and the fourth electronic expansion valve 20. The outlet of the main condenser 7 is connected to the liquid inlet of the liquid reservoir 4 through the second one-way valve 8. The liquid outlet of the liquid reservoir 4 is connected to the first liquid inlet of the intercooler 3 through a pipeline, and is connected to the second liquid inlet of the intercooler 3 through the first throttle valve 9. The air outlet of the intercooler 3 is connected to the air inlet of the high-pressure compressor 2, and the liquid outlet of the intercooler 3 is connected to the liquid inlet of the evaporator 11 through the second throttle valve 19. The air outlet of the evaporator 11 is connected to the air inlet of the low-pressure compressor 1.

[0025] The rotary dehumidification system includes a dehumidification rotary wheel 13, a total heat exchanger 14, a regeneration fan 10, a dehumidification fan 12 and a drying box 15. The dehumidification outlet of the dehumidification rotary wheel 13 is connected to the first air inlet of the total heat exchanger 14 through an air duct, the first air outlet of the total heat exchanger 14 is connected to the air inlet of the main condenser 7 through an air duct, the air outlet of the main condenser 7 is connected to the air inlet of the drying box 15, the air outlet of the drying box 15 is connected to the air inlet of the evaporator 11 through an air duct, the air outlet of the evaporator 11 is connected to the dehumidification fan 12 through an air duct, and the dehumidification fan is connected to the dehumidification inlet of the dehumidification rotary wheel 13 through an air duct. The air outlet of the auxiliary condenser 6 is connected to the second inlet of the second heat exchanger 34 through the air duct, the second outlet of the second heat exchanger 34 is connected to the second inlet of the first heat exchanger 33 through the air duct, the second outlet of the first heat exchanger 33 is connected to the regeneration fan 10 through the air duct, the regeneration fan 10 is connected to the regeneration inlet of the dehumidification wheel 13 through the air duct, the regeneration outlet of the dehumidification wheel 13 is connected to the second air inlet of the total heat exchanger 14 through the air duct, and the second air outlet of the total heat exchanger 14 is connected to the outside.

[0026] The present invention drives a two-stage compression heat pump system to operate through a hydrogen engine, and performs drying and dehumidification through a rotary dehumidification system.

[0027] A hydrogen-driven coupled rotary dehumidification two-stage compression heat pump drying method, which specifically includes: In the hydrogen fuel supply system, the supply of hydrogen fuel in the first hydrogen bottle 44 is controlled by adjusting the opening of the first switch valve 41. The high-pressure hydrogen stored in the first hydrogen bottle 44 is adjusted to a suitable working pressure by the pressure regulator 46 and then enters the hydrogen filter 42. The hydrogen filter 42 filters out other impurities in the hydrogen. The filtered hydrogen enters the mass flow meter 49 and enters the hydrogen mixer 38 to mix with air. The mixed gas enters the hydrogen engine 22 through the flame arrester 37. When an emergency occurs, the first emergency shut-off valve 47 is closed to stop the supply of high-pressure hydrogen. The pressure of the high-pressure hydrogen entering the system is adjusted by the pressure regulator 46 to keep it stable. The hydrogen entering the hydrogen engine 22 is measured by the mass flow meter 49.

[0028] In the hydrogen fuel supply system, when the system needs to be maintained, repaired or fails, in order to safely handle the residual hydrogen in the system, the second hydrogen bottle 48 can be used to collect the residual hydrogen and prevent hydrogen leakage. At this time, the second switch valve 43 and the third switch valve 45 are opened, the first switch valve 41 is closed, and the hydrogen supply of the first hydrogen bottle 44 is stopped. The residual hydrogen in the system slowly flows into the second hydrogen bottle 48 through the second switch valve 43 and the third switch valve 45 under the action of the pressure difference. During the collection process, the pressure and flow of hydrogen flowing into the second hydrogen bottle 48 are monitored by the first pressure sensor 39 and the mass flow meter 49. The collected hydrogen is stored in the second hydrogen bottle 48. At this time, the second switch valve 43 and the third switch valve 45 are opened, and the first switch valve 41 is opened. The hydrogen in the second hydrogen bottle 48 is mixed with the hydrogen filtered by the hydrogen filter 42 and enters the mass flow meter 49 to continue to provide hydrogen for the hydrogen fuel supply system.

[0029] The upstream hydrogen fuel system continuously provides hydrogen under constant pressure and cuts off the supply of hydrogen in an emergency. The main functions of the downstream hydrogen fuel supply system are to meter and ensure that hydrogen is delivered to the hydrogen engine drive system in an appropriate manner and to prevent backfire. Since the flame arrester 37 is large in size, it can meet the requirements of the smooth passage of hydrogen and air mixture. The flame arrester 37 can block the propagation of hydrogen flame caused by backfire, and at the same time, the pressure relief valve 36 can reduce the pressure of the intake system caused by backfire.

[0030] The hydrogen engine 22 drives the first pulley 23 to rotate by doing work, thereby driving the second pulley 24 and the third pulley 27 to rotate. Through the rotation of the pulley, the first coupling 25 and the second coupling 29 are driven to operate, and the first gearbox 26 and the second gearbox 28 are further driven to operate, thereby driving the low-pressure compressor 1 and the high-pressure compressor 2 to operate. The flue gas discharged by the hydrogen engine 22 recovers the heat of the flue gas through the flue gas heat exchanger 32, exchanges heat with the cooling water, heats the cooling water, and discharges the flue gas after heat release to the outside, so as to realize the waste heat recovery of the flue gas. The cooling water after heat exchange with the flue gas exchanges heat with the regeneration air through the second water pump 31 and the first heat exchanger 33, heats the regeneration air, and increases the temperature of the regeneration air. In addition, the waste heat generated by the hydrogen engine 22 exchanges heat with the cooling water, and the cooling water exchanges heat with the regeneration air through the first water pump 30 and the second heat exchanger 34, and the regeneration air is heated by the first heat exchanger 33 and the second heat exchanger 34, further increasing the temperature of the regeneration air.

[0031] The high-pressure liquid coming out of the main condenser 7 first enters the liquid storage tank 4 for storage, and then is divided into two paths. One path is throttled by the intercooler 3 and the first throttle valve 9, and its pressure is reduced to the intermediate pressure, and evaporates in the intercooler 3; the other part flows through the intercooler 3 in the coil, and exchanges heat with the refrigerant vapor evaporated at the intermediate pressure outside the tube through the coil to achieve the purpose of supercooling, and then evaporates and refrigerates in the evaporator 11. The saturated refrigerant vapor coming out of the evaporator 11 is sucked in by the low-pressure compressor 1, compressed to the intermediate pressure, and discharged to the high-pressure compressor 2. After mixing with the saturated vapor coming out of the intercooler 3, it enters the high-pressure compressor 2 and is compressed to the condensation pressure, condensed into high-pressure liquid in the main condenser 7, and then circulated again.

[0032] like Figure 2 As shown in the figure, the dehumidification wheel is divided into two areas: the regeneration area and the dehumidification area. The operating mechanism of the rotary dehumidifier includes two processes: dehumidification and regeneration. During the dehumidification process, humid air enters the dehumidification area of ​​the wheel, and the water vapor in it is adsorbed by the desiccant, and the air becomes dry. As the wheel rotates, it enters the regeneration area, and the desiccant is desorbed by heating the regenerated air to restore its moisture absorption capacity. The regenerated air loses sensible heat due to the desorption process, becomes humid air and is discharged outdoors, completing the moisture transfer.

[0033] In this system, after the dry air dries the material in the drying chamber 15, it passes through the evaporator 11 for heat exchange, releases heat to reduce the temperature, and the air with reduced temperature enters the dehumidification area of ​​the dehumidification wheel 13 for dehumidification under the action of the dehumidification fan 12. The dehumidified dry air passes through the total heat exchanger 14 and the main condenser 7 for heat exchange to increase the air temperature, forming high-temperature dry air and then enters the drying chamber 15 to dry the material. Under the action of the regeneration fan 10, the regenerated air first passes through the auxiliary condenser 6 for heat exchange to increase the regeneration temperature, and then passes through the first heat exchanger 33 and the second heat exchanger 34 in sequence for heat exchange to further increase the regeneration temperature, and then enters the regeneration area of ​​the dehumidification wheel 13. The regenerated air can enter the total heat exchanger 14 to exchange heat with the dehumidified air and recycle the heat. In addition, the opening of the first electronic expansion valve 16 can be adjusted to control the refrigerant flow entering the auxiliary condenser 6, and the temperature of the regenerated air can be controlled by heat exchange with the regenerated air. The series-parallel connection of the main condenser 7 and the auxiliary condenser 6 can be achieved by adjusting the opening of the third electronic expansion valve 18 and the fourth electronic expansion valve 20.

[0034] It should be understood that the parts not elaborated in detail in this specification belong to the prior art. The above embodiments are only descriptions of the preferred implementation methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made by ordinary engineers and technicians in this field to the technical solution of the present invention should fall within the protection scope determined by the claims of the present invention.

Claims

1. A two-stage heat pump drying system driven by hydrogen and coupled with a rotary dehumidifier, characterized in that: It includes a hydrogen fuel supply system, a hydrogen engine drive system, a two-stage compression heat pump system and a rotary dehumidification system; The hydrogen fuel supply system comprises an upstream hydrogen fuel system and a downstream hydrogen fuel system; the upstream hydrogen fuel system comprises a plurality of first hydrogen cylinders connected in parallel, each of the first hydrogen cylinders is connected to a pressure regulator via a switch valve, the pressure regulator is connected to an inlet of a hydrogen filter via a first emergency shut-off valve, the outlet of the hydrogen filter is connected to an inlet of a mass flow meter via a first pressure sensor, the second hydrogen cylinder is connected to the first pressure sensor via a second switch valve and a third switch valve, the outlet of the mass flow meter is connected to a hydrogen inlet of a hydrogen mixer via a second pressure sensor, the hydrogen mixer is arranged below an inlet of a flame arrester, the outlet of the flame arrester is connected to a hydrogen engine via a second emergency shut-off valve, and the flame arrester is connected to a pressure release valve; The hydrogen engine driving system comprises a hydrogen engine, wherein the hydrogen engine is connected to a second pulley and a third pulley via a first pulley, the second pulley is connected to a high-pressure compressor of a two-stage compression heat pump system via a first coupling and a first gearbox; the third pulley is connected to a low-pressure compressor of the two-stage compression heat pump system via a second coupling and a second gearbox; the first outlet of the hydrogen engine is connected to a first inlet of a second heat exchanger via a first water pump, and the first outlet of the second heat exchanger is connected to an inlet of the hydrogen engine; the second outlet of the hydrogen engine is connected to a first inlet of a flue gas heater, the first outlet of the flue gas heat exchanger outputs flue gas to the outside, the second outlet of the flue gas heater is connected to a first inlet of a first heat exchanger via a second water pump, and the first outlet of the first heat exchanger is connected to a second inlet of the flue gas heat exchanger; The two-stage compression heat pump system includes a low-pressure compressor, a refrigerant outlet of the low-pressure compressor is connected to the refrigerant inlet of the high-pressure compressor through a third one-way valve, the refrigerant outlet of the high-pressure compressor is connected to the inlet of the main condenser through the second electronic expansion valve in one way, and is connected to the inlet of the auxiliary condenser through the first electronic expansion valve in another way, the outlet of the auxiliary condenser is connected to the inlet of the main condenser through the third electronic expansion valve in one way, and is connected to the liquid inlet of the liquid reservoir through the first one-way valve and the fourth electronic expansion valve in another way; the outlet of the main condenser is connected to the liquid inlet of the liquid reservoir through the second one-way valve; the liquid outlet of the liquid reservoir is connected to the first liquid inlet of the intercooler through a pipeline in one way, and is connected to the second liquid inlet of the intercooler through the first throttle valve in another way, the air outlet of the intercooler is connected to the air inlet of the high-pressure compressor, the liquid outlet of the intercooler is connected to the liquid inlet of the evaporator through the second throttle valve, and the air outlet of the evaporator is connected to the air inlet of the low-pressure compressor; The rotary dehumidification system includes a dehumidification wheel, a dehumidification outlet of the dehumidification wheel is connected to the first air inlet of the total heat exchanger through an air duct, the first air outlet of the total heat exchanger is connected to the air inlet of the main condenser through the air duct, the air outlet of the main condenser is connected to the air inlet of the drying box, the air outlet of the drying box is connected to the air inlet of the evaporator through the air duct, the air outlet of the evaporator is connected to the dehumidification fan through the air duct, and the dehumidification fan is connected to the dehumidification inlet of the dehumidification wheel through the air duct; the air outlet of the auxiliary condenser is connected to the second inlet of the second heat exchanger through the air duct, the second outlet of the second heat exchanger is connected to the second inlet of the first heat exchanger through the air duct, the second outlet of the first heat exchanger is connected to the regeneration fan through the air duct, the regeneration fan is connected to the regeneration inlet of the dehumidification wheel through the air duct, the regeneration outlet of the dehumidification wheel is connected to the second air inlet of the total heat exchanger through the air duct, and the second air outlet of the total heat exchanger is connected to the outside.

2. A two-stage heat pump drying system driven by hydrogen and coupled with a rotary dehumidifier according to claim 1, characterized in that The hydrogen mixer is 15.25 cm away from the inlet of the flame arrester.

3. A two-stage heat pump drying method with hydrogen driven coupled rotary dehumidification, characterized in that: Specifically include: The high-pressure hydrogen in the first hydrogen cylinder enters the hydrogen filter through the pressure regulator, and the hydrogen filter filters out other impurities in the hydrogen. The filtered hydrogen enters the mass flow meter, enters the hydrogen mixer and mixes with air, and the mixed gas enters the hydrogen engine through the flame arrester; the supply of high-pressure hydrogen in the first hydrogen cylinder is controlled by adjusting the opening of the first switch valve; when an emergency occurs, the first emergency shut-off valve is closed to stop the supply of high-pressure hydrogen; the pressure of the high-pressure hydrogen entering the system is adjusted by the pressure regulator; the hydrogen entering the hydrogen engine is measured by the mass flow meter; The second switch valve and the third switch valve are opened, and the first switch valve is closed. The hydrogen remaining in the system slowly flows into the second hydrogen cylinder through the second switch valve and the third switch valve; the pressure and flow of the hydrogen flowing into the second hydrogen cylinder are monitored by the first pressure sensor and the mass flow meter; the collected hydrogen is stored in the second hydrogen cylinder, and at this time, the second switch valve and the third switch valve are opened, and the first switch valve is opened, and the hydrogen in the second hydrogen cylinder and the hydrogen filtered by the hydrogen filter are mixed into the mass flow meter to continue to provide hydrogen for the hydrogen fuel supply system; The hydrogen engine drives the first pulley to rotate, thereby driving the second pulley and the third pulley to rotate, and through the rotation of the pulley, drives the first coupling and the second coupling to operate, further drives the first gearbox and the second gearbox to operate, and drives the high-pressure compressor and the low-pressure compressor to operate; the flue gas discharged by the hydrogen engine recovers the heat of the flue gas through the flue gas heat exchanger, exchanges heat with cooling water, heats the cooling water, and discharges the heat-released flue gas to the outside; the cooling water after heat exchange with the flue gas exchanges heat with the regeneration air through the second water pump and the first heat exchanger, and heats the regeneration air; the waste heat generated by the hydrogen engine exchanges heat with the cooling water, and the cooling water then exchanges heat with the regeneration air through the first water pump and the second heat exchanger, and the regeneration air is heated by the first heat exchanger and the second heat exchanger; The high-pressure liquid coming out of the main condenser first enters the liquid storage tank for storage, and then is divided into two paths. One path passes through the intercooler and the first throttle valve to reduce its pressure to the intermediate pressure and evaporate in the intercooler; the other part flows through the intercooler in the coil, exchanges heat with the refrigerant vapor evaporated at the intermediate pressure outside the tube through the coil, and then evaporates and refrigerates in the evaporator; the saturated refrigerant vapor coming out of the evaporator is sucked in by the low-pressure compressor and compressed to the intermediate pressure, and then discharged to the high-pressure compressor, mixed with the saturated vapor coming out of the intercooler, and then enters the high-pressure compressor to be compressed to the condensation pressure, condensed into high-pressure liquid in the main condenser, and then circulated again; The operation of the rotary dehumidifier includes two processes: dehumidification and regeneration. During the dehumidification process, humid air enters the dehumidification area of ​​the rotary wheel, where the water vapor is adsorbed by the desiccant and the air becomes dry. As the rotary wheel rotates, it enters the regeneration area, where the desiccant is desorbed by heating the regenerated air to restore its moisture absorption capacity. The regenerated air loses sensible heat during the desorption process and becomes humid air and is discharged outdoors, completing the moisture transfer. After the dry air dries the material in the drying room, it passes through the evaporator for heat exchange, releases heat to reduce the temperature, and the air with reduced temperature enters the dehumidification zone of the dehumidification wheel for dehumidification under the action of the dehumidification fan. The dehumidified dry air passes through the total heat exchanger and the main condenser for heat exchange to increase the air temperature, forming high-temperature dry air and then enters the drying room to dry the material; under the action of the regeneration fan, the regenerated air first passes through the auxiliary condenser for heat exchange to increase the regeneration temperature, and then passes through the second heat exchanger and the first heat exchanger in turn for heat exchange to further increase the regeneration temperature, and then enters the regeneration zone of the dehumidification wheel. The regenerated air can enter the total heat exchanger to exchange heat with the dehumidified air and recycle the heat; by adjusting the opening of the first electronic expansion valve, the refrigerant flow entering the auxiliary condenser is controlled, and the temperature of the regeneration air can be controlled by heat exchange with the regeneration air. By adjusting the switches of the third electronic expansion valve and the fourth electronic expansion valve, the series and parallel connection of the main condenser and the auxiliary condenser can be realized.

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