Efficient vacuum freeze-drying system for preparing dry traditional Chinese medicinal materials and working process of efficient vacuum freeze-drying system

Abstract

The invention relates to an efficient vacuum freeze-drying system for preparing dry traditional Chinese medicinal materials. The efficient vacuum freeze-drying system comprises a compressed air circulation assembly and a refrigeration assembly. The compressed air circulation assembly comprises an air compressor, a first evaporator and a low-pressure jet pump. The air compressor, the first evaporator and the low-pressure jet pump are connected in a closed loop mode in the working medium flowing direction. The air compressor, the first evaporator and the freezing chamber are connected in a closed loop mode in the working medium flowing direction. The refrigeration assembly comprises a compressor, a condenser, a current converter, a second evaporator and a cold trap; the compressor, the condenser and the first evaporator are connected in a closed loop mode in the flowing direction of refrigerants. The compressor, the condenser and the second evaporator are connected in a closed loop mode in the flowing direction of refrigerants. The compressor, the condenser, the current converter and the cold trap are connected in a closed loop mode in the flowing direction of refrigerants. The compressor, the current converter and the cold trap are connected in a closed loop mode in the flowing direction of refrigerants. And the low-pressure jet pump is connected with the cold trap. According to the system, the heat exchange efficiency can be improved, the cold trap chamber can be effectively defrosted, the working efficiency is improved, and the energy consumption is reduced.

Description

Technical Field

[0001] The invention relates to a vacuum freeze drying system, in particular to a high-efficiency vacuum freeze drying system for preparing dry Chinese medicinal materials. Background Art

[0002] Vacuum drying technology refers to the process in which the pressure of the environment in which the material is dried is lower than the standard atmospheric pressure. The saturation temperature of water vapor decreases as the pressure decreases, so that the water in the material can evaporate under low temperature conditions to achieve the purpose of drying; vacuum freeze drying technology is to first freeze the material at a low temperature (-50 to -10°C), and then directly sublimate the solid water in the material into a gaseous state under a high vacuum to achieve the purpose of drying. The vacuum freeze drying technology can keep the shape of the material basically unchanged after drying, forming a porous material structure, which can retain the material components in the material to the maximum extent. At present, the vacuum freeze drying system for preparing dry Chinese medicinal materials is limited by conditions such as low heat exchange temperature and the vacuum environment in the vacuum drying room is not conducive to heat exchange. The efficiency of the traditional vacuum freeze drying system is not high overall, and the frost on the cold trap in the system will further hinder the heat exchange efficiency. For example, Chinese patent document CN2019218325260 discloses a vacuum freeze drying box for the production of high-end Chinese medicinal materials, and Chinese patent document CN2023108694931 discloses a freeze drying system for Chinese herbal medicine slices; the systems disclosed in the above two existing patent documents both lack efficient pre-desiccant of items in the freezer, and the cold trap system in the vacuum freeze drying system is difficult to perform technical processing to effectively defrost the cold trap heat exchanger under uninterrupted normal operation, resulting in low overall efficiency and high energy consumption.

[0003] Therefore, it is necessary to further improve the existing vacuum freeze-drying system. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and to provide a high-efficiency vacuum freeze-drying system for preparing dry Chinese medicinal materials. The system can effectively pre-dry the items in the freezer, improve the heat exchange efficiency of the freezer, and effectively rotate defrost while the cold trap chamber is operating normally and uninterruptedly, thereby improving the overall work efficiency and significantly reducing energy consumption.

[0005] The object of the present invention is achieved in that: A high-efficiency vacuum freeze-drying system for preparing dried Chinese medicinal materials, comprising a compressed air circulation component for cooling compressed air, and a refrigeration component for rotation defrosting; wherein: The compressed air circulation component includes an air compressor, a first evaporator, and a low-pressure ejector pump; the air compressor, the first evaporator, and the low-pressure ejector pump are connected in a closed loop along the flow direction of the working medium; the air compressor, the first evaporator, and the freezing chamber are connected in a closed loop along the flow direction of the working medium; The refrigeration assembly includes a compressor, a condenser, an inverter, a second evaporator and a cold trap; the compressor, the condenser and the first evaporator are connected in a closed loop along the refrigerant flow direction; the compressor, the condenser and the second evaporator are connected in a closed loop along the refrigerant flow direction; the compressor, the condenser, the inverter and the cold trap are connected in a closed loop along the refrigerant flow direction; the compressor, the inverter and the cold trap are connected in a closed loop along the refrigerant flow direction; the low-pressure ejector pump is connected to the cold trap; the second evaporator is arranged in the freezing chamber, and the cold trap is arranged in the vacuum drying chamber.

[0006] As a specific solution, the inverter includes a first inverter inlet connected to the condenser, a second inverter inlet connected to the compressor, a third inverter inlet connected to the compressor, a first inverter total outlet, a second inverter total outlet and an inverter component; the cold trap includes a third refrigerant tube winding for implementing defrost operation mode one, and a fourth refrigerant tube winding for implementing defrost operation mode two, the first inverter total outlet is connected to the fourth refrigerant tube winding, and the second inverter total outlet is connected to the third refrigerant tube winding; in the refrigeration operation mode, the inverter component regulates the first inverter inlet to connect to the first inverter total outlet and the second inverter total outlet respectively; in the defrost operation mode, the inverter component regulates the second inverter inlet to connect to the first inverter total outlet, and the third inverter inlet to connect to the second inverter total outlet.

[0007] As another specific scheme, the converter assembly includes a first converter chamber, a second converter chamber and a third converter chamber, the first converter chamber is connected to the second converter chamber and the third converter chamber respectively, the first converter inlet is connected to the first converter chamber, the second converter inlet is connected to the second converter chamber, and the third converter inlet is connected to the third converter chamber; a first slider is slidably arranged in the second converter chamber, and the second converter chamber is provided with a first converter outlet and a second converter outlet respectively connected to the first converter total outlet, when the first slider slides to the first station, the first converter inlet is connected to the first converter outlet, when the first slider slides to the second station, the second converter inlet is connected to the second converter outlet; a second slider is slidably arranged in the third converter chamber, and the third converter chamber is provided with a third converter outlet and a fourth converter outlet respectively connected to the second converter total outlet, when the second slider slides to the first station, the first converter inlet is connected to the fourth converter outlet, and when the second slider slides to the second station, the third converter inlet is connected to the third converter outlet.

[0008] As another specific scheme, the cold trap device includes a cold trap cylinder and an insulating partition, the insulating partition divides the inner cavity of the cold trap cylinder into an outer trap chamber and an inner trap chamber, the third refrigerant pipe winding is arranged in the outer trap chamber, and the fourth refrigerant pipe winding is arranged in the inner trap chamber; the outer trap chamber and the inner trap chamber are respectively connected to a low-pressure ejector pump.

[0009] As another specific scheme, the low-pressure ejector pump includes a high-pressure end inlet, an ejector chamber, a mixing chamber, and an ejector pump outlet which are connected in sequence along the flow direction of the working medium; the first evaporator is connected to the high-pressure end inlet, and the ejector pump outlet is connected to the air compressor; the outer trap chamber and the inner trap chamber are respectively connected to the ejector chamber.

[0010] As another specific scheme, a control component is arranged between the cold trap and the compressor, and the control component includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a sixth solenoid valve and a fifth expansion valve; the first solenoid valve and the sixth solenoid valve are connected in parallel between the fourth refrigerant pipe winding and the compressor, and the second solenoid valve and the third solenoid valve are connected in parallel between the third refrigerant pipe winding and the compressor; the fifth expansion valve is connected in series with the third solenoid valve and the sixth solenoid valve, respectively.

[0011] As another specific scheme, the first evaporator includes a first refrigerant tube winding and a first refrigeration shell, and the first refrigerant tube winding is arranged in the first refrigeration shell; the inlet end of the first refrigerant tube winding is connected to the condenser, and the outlet end of the first refrigerant tube winding is connected to the compressor; the inlet end of the first refrigeration shell is connected to the air compressor, and the outlet end of the first refrigeration shell is connected to the low-pressure ejector pump.

[0012] As another specific solution, a first expansion valve is provided between the low-pressure ejector pump and the air compressor; and a third expansion valve is provided between the first evaporator and the freezing chamber.

[0013] As another specific solution, a sixth expansion valve is provided between the condenser and the first evaporator; a fourth expansion valve is provided between the condenser and the second evaporator; and a second expansion valve is provided between the condenser and the inverter.

[0014] The working process of the above-mentioned efficient vacuum freeze-drying system includes: (I) Working process of compressed air circulation components: The air compressor sucks in normal-pressure air from the freezer for compression and then discharges it into the first evaporator for cooling and dehumidification. After dehumidification, the low-temperature compressed air is discharged from the first evaporator; part of the low-temperature compressed air is reduced in pressure to normal pressure and then enters the freezer to freeze and cool the items. The normal-pressure air in the freezer is discharged and then re-enters the air compressor for compression, thereby realizing the circulation compression of air; part of the low-temperature compressed air enters the low-pressure ejector pump for high-speed injection to form high-pressure and high-speed compressed air. A local vacuum environment is established inside the low-pressure ejector pump to suck in the air and water vapor in the cold trap. The air and water vapor are mixed with the high-pressure and high-speed compressed air and then reduced in pressure and re-enter the air compressor for compression; (II) Refrigeration component workflow: (a1) Non-defrosting operation mode: The refrigerant flows through the compressor and condenser in sequence and is divided into three branches: The refrigerant through the first branch enters the first evaporator to evaporate, cools the compressed air, and then returns to the compressor to be compressed; The refrigerant through the second branch enters the second evaporator to cool the air and items in the freezer, and then returns to the compressor for compression; The refrigerant through the third branch enters the inverter, and then enters the cold trap to condense and capture the water vapor generated by sublimation in the vacuum drying chamber. Part of the water vapor generated by sublimation in the vacuum drying chamber is discharged by the low-pressure ejector pump, and the refrigerant after heat exchange returns to the compressor for compression; (a2) Defrost operation mode: ①. Defrost operation mode 1: The refrigerant flows through the compressor and condenser in sequence and is divided into three branches: The refrigerant through the first branch enters the first evaporator to evaporate, cools the compressed air, and then returns to the compressor to be compressed; The refrigerant through the second branch enters the second evaporator to cool the air and items in the freezer, and then returns to the compressor for compression; The refrigerant through the third branch enters the inverter, and the low-temperature refrigerant enters the cold trap to condense and capture the water vapor generated by sublimation in the vacuum drying chamber. Part of the water vapor generated by sublimation in the vacuum drying chamber is discharged by the low-pressure ejector pump, and the refrigerant after heat exchange returns to the compressor for compression; in addition, the high-temperature and high-pressure refrigerant enters the inverter, and the high-temperature and high-pressure refrigerant enters the cold trap for heat release and defrosting. The water vapor sublimated by defrosting is sucked and discharged by the low-pressure ejector pump, and the refrigerant after heat release returns to the compressor for compression after pressure reduction; ②Defrosting operation mode 2: The refrigerant flows through the compressor and condenser in sequence and is divided into three branches: The refrigerant through the first branch enters the first evaporator to evaporate, cools the compressed air, and then returns to the compressor to be compressed; The refrigerant through the second branch enters the second evaporator to cool the air and items in the freezer, and then returns to the compressor for compression; The refrigerant through the third branch enters the inverter, and the low-temperature refrigerant enters the cold trap to condense and capture the water vapor generated by sublimation in the vacuum drying chamber. Part of the water vapor generated by sublimation in the vacuum drying chamber is discharged by the low-pressure ejector pump, and the refrigerant after heat exchange returns to the compressor for compression; in addition, the high-temperature and high-pressure refrigerant enters the inverter, and the high-temperature and high-pressure refrigerant enters the cold trap for heat release and defrosting. The water vapor sublimated by defrosting is sucked and discharged by the low-pressure ejector pump, and the refrigerant after heat release returns to the compressor for compression after pressure reduction.

[0015] The beneficial effects of the present invention are as follows: This refrigeration component can effectively dehumidify and defrost: low-temperature refrigerant enters the cold trap to condense and capture the water vapor generated by sublimation in the vacuum drying chamber, and part of the water vapor generated by sublimation in the vacuum drying chamber is discharged by the low-pressure ejector pump, and the refrigerant after heat exchange returns to the compressor for compression; in addition, high-temperature and high-pressure refrigerant enters the inverter, and high-temperature and high-pressure refrigerant enters the cold trap for heat release and defrosting, and the water vapor sublimated by defrosting is sucked and discharged by the low-pressure ejector pump, and the refrigerant after heat release returns to the compressor for compression after pressure reduction. It effectively solves the technical problems that the current vacuum freeze-drying system is limited by conditions such as low heat exchange temperature and vacuum environment in the vacuum drying chamber that is not conducive to heat exchange, resulting in low overall efficiency and cold trap frost hindering heat exchange efficiency. The high-efficiency vacuum freeze-drying system can pre-dehumidify the items in the freezer efficiently, and the cold trap can perform effective defrosting technical processing under uninterrupted normal operation, greatly improving the overall efficiency and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of a vacuum freeze-drying system in one embodiment of the present invention.

[0017] Figure 2 Schematic diagram of an airflow organization system with cooling compressed air in one embodiment of the present invention.

[0018] Figure 3 It is a partial cross-sectional view of a refrigeration assembly in one embodiment of the present invention.

[0019] Figure 4 4 is a cross-sectional view of a low-pressure ejector pump according to an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] See also Figure 1-Figure 4 The high-efficiency vacuum freeze-drying system for preparing dried Chinese medicinal materials involved in this embodiment includes a compressed air circulation component for cooling compressed air and a refrigeration component for rotating defrosting; wherein, The compressed air circulation component includes an air compressor 1, a first evaporator 2, and a low-pressure ejector pump 3; the air compressor 1, the first evaporator 2, and the low-pressure ejector pump 3 are connected in a closed loop along the working medium flow direction; the air compressor 1, the first evaporator 2, and the freezing chamber A are connected in a closed loop along the working medium flow direction; The refrigeration component includes a compressor 4, a condenser 5, an inverter 6, a second evaporator 10 and a cold trap 7; the compressor 4, the condenser 5 and the first evaporator 2 are connected in a closed loop along the refrigerant flow direction; the compressor 4, the condenser 5 and the second evaporator 10 are connected in a closed loop along the refrigerant flow direction; the compressor 4, the condenser 5, the inverter 6 and the cold trap 7 are connected in a closed loop along the refrigerant flow direction, and a gas-liquid separator 11 is also connected between the compressor 4 and the cold trap 7; the compressor 4, the inverter 6 and the cold trap 7 are connected in a closed loop along the refrigerant flow direction; the low-pressure ejector pump 3 is connected to the cold trap 7; the second evaporator 10 is arranged in the freezing chamber A, the cold trap 7 and the electric heater 13 are respectively arranged in the vacuum drying chamber B, and the electric heater 13 is used to heat and sublimate the indoor materials to precipitate moisture; wherein, the low-pressure ejector pump 3, the inverter 6 and the cold trap 7 together constitute a cold trap system.

[0022] Further, see Figure 3 The inverter 6 includes a first inverter inlet 65 connected to the condenser 5, a second inverter inlet 67 connected to the compressor 4, a third inverter inlet 63 connected to the compressor 4, a first inverter total outlet 612, a second inverter total outlet 613 and an inverter assembly; the outlet of the compressor 4 is connected to the second inverter inlet 67 through a fifth solenoid valve 95, and the outlet of the compressor 4 is connected to the third inverter inlet 63 through a fourth solenoid valve 94; the cold trap 7 includes a third refrigerant pipe winding 71 for implementing the defrosting operation mode 1, and a first refrigerant pipe winding 71 for implementing the defrosting operation mode 1, and a second ... In the second defrost operation mode, the fourth refrigerant tube winding 72, the first converter outlet 612 is connected to the fourth refrigerant tube winding 72, and the second converter outlet 613 is connected to the third refrigerant tube winding 71; in the refrigeration operation mode, the converter component regulates the first converter inlet 65 to connect the first converter outlet 612 and the second converter outlet 613 respectively; in the defrost operation mode, the converter component regulates the second converter inlet 67 to connect the first converter outlet 612, and the third converter inlet 63 to connect the second converter outlet 613.

[0023] Furthermore, the converter assembly includes a first converter chamber 61, a second converter chamber 62 and a third converter chamber 60, the first converter chamber 61 is connected to the second converter chamber 62 and the third converter chamber 60 respectively, the first converter inlet 65 is connected to the first converter chamber 61, the second converter inlet 67 is connected to the second converter chamber 62, and the third converter inlet 63 is connected to the third converter chamber 60; a first slider 66 is slidably arranged in the second converter chamber 62, and a first converter outlet 610 and a second converter outlet 611 are arranged on the second converter chamber 62, which are respectively connected to the first converter total outlet 612. When the first slider 66 slides to the first When the first converter chamber 61 is in the working position, the first converter inlet 65 is connected to the first converter outlet 610, and when the first slider 66 slides to the second working position, the second converter inlet 67 is connected to the second converter outlet 611; a second slider 64 is slidably arranged in the third converter chamber 60, and a third converter outlet 68 and a fourth converter outlet 69 respectively connected to the second converter total outlet 613 are arranged on the third converter chamber 60, when the second slider 64 slides to the first working position, the first converter inlet 65 is connected to the fourth converter outlet 69, and when the second slider 64 slides to the second working position, the third converter inlet 63 is connected to the third converter outlet 68.

[0024] Furthermore, the first converter chamber 61, the second converter chamber 62 and the third converter chamber 60 are coaxially matched with each other, wherein the second converter chamber 62 and the third converter chamber 60 are respectively arranged at the coaxial ends of the first converter chamber 61, and a partition 614 is arranged between the two adjacent converter chambers. The partition 614 is provided with a through hole 615, and the two adjacent converter chambers are connected to each other through the through hole 615 between each other. Specifically, the first converter outlet 610 and the second converter outlet 611 are respectively arranged on the radial wall surface of the second converter chamber 62 along the axial direction close to the two end surfaces. When the first slider 66 slides to either end, the first slider 66 can always block the first converter outlet 610 or the second converter outlet 611 at the corresponding end, and the first converter outlet 610 and the second converter outlet 611 finally converge into the first converter total outlet 612; the third converter outlet 68 and the fourth converter outlet 69 are respectively arranged on the radial wall surface of the third converter chamber 60 along the axial direction close to the two end surfaces. When the second slider 64 slides to either end, the second slider 64 can always block the third converter outlet 68 or the fourth converter outlet 69 at the corresponding end, and the third converter outlet 68 and the fourth converter outlet 69 finally converge into the second converter total outlet 613.

[0025] Further, see Figure 3 The cold trap device 7 includes a cold trap cylinder body 70 and a sleeve-shaped insulating partition 73. The insulating partition 73 divides the inner cavity of the cold trap cylinder body 70 into an outer trap chamber 74 and an inner trap chamber 75. The outer trap chamber 74 and the inner trap chamber 75 are respectively in the shape of a sleeve with an open top and a closed bottom. The third refrigerant pipe winding 71 is arranged in the outer trap chamber 74, and the fourth refrigerant pipe winding 72 is arranged in the inner trap chamber 75. The outer trap chamber 74 and the inner trap chamber 75 are respectively connected to the low-pressure ejector pump 3.

[0026] Further, see Figure 4 The low-pressure ejector pump 3 includes a high-pressure end inlet 30, an ejection chamber 35, a mixing chamber 33, and an ejector pump outlet 34 connected in sequence along the working medium flow direction; the outlet end of the first refrigeration shell 25 on the first evaporator 2 is connected to the high-pressure end inlet 30, and the ejector pump outlet 34 is connected to the inlet end of the air compressor 1; the outer trap chamber 74 and the inner trap chamber 75 are respectively connected to the ejector chamber 35. Specifically, the ejector chamber 35 is provided with a first low-pressure end inlet 31 and a second low-pressure end inlet 32 ​​extending in parallel with each other, the first low-pressure end inlet 31 extends into the outer trap chamber 74, and the second low-pressure end inlet 32 ​​extends into the inner trap chamber 75; the low-pressure ejector pump 3 can be a single-stage or multi-stage ejector pump. Preferably, the low-pressure ejector pump 3 of this embodiment is selected with a minimum of two low-pressure end ejector pumps to maintain the absolute pressure of the vacuum drying chamber B <10 kPa.

[0027] Further, see Figure 3 A control component is provided between the cold trap 7 and the compressor 4. Specifically, the control component is connected to the compressor 4 through the gas-liquid separator 11; the control component includes a first solenoid valve 91, a second solenoid valve 92, a third solenoid valve 93, a sixth solenoid valve 96 and a fifth expansion valve 85; the first solenoid valve 91 and the sixth solenoid valve 96 are connected in parallel between the fourth refrigerant pipe winding 72 and the compressor 4, and the second solenoid valve 92 and the third solenoid valve 93 are connected in parallel between the third refrigerant pipe winding 71 and the compressor 4; the fifth expansion valve 85 is connected in series with the third solenoid valve 93 and the sixth solenoid valve 96, respectively. Specifically, the outlet end of the fourth refrigerant pipe winding 72 and the inlet end of the gas-liquid separator 11 are respectively connected by two parallel branches, one of which is provided with a second solenoid valve 92, and the other branch is provided with a third solenoid valve 93 and a fifth expansion valve 85 in sequence along the flow direction of the working fluid; the outlet end of the third refrigerant pipe winding 71 and the inlet end of the gas-liquid separator 11 are respectively connected by two parallel branches, one of which is provided with a first solenoid valve 91, and the other branch is provided with a sixth solenoid valve 96 and a fifth expansion valve 85 in sequence along the flow direction of the working fluid.

[0028] Further, see Figure 2 The first evaporator 2 includes a first refrigerant tube winding 22 and a first refrigeration shell 25, and the first refrigerant tube winding 22 is arranged in the first refrigeration shell 25; the inlet end of the first refrigerant tube winding 22 is connected to the condenser 5, and the outlet end of the first refrigerant tube winding 22 is connected to the compressor 4; the inlet end of the first refrigeration shell 25 is connected to the air compressor 1, and the outlet end of the first refrigeration shell 25 is connected to the low-pressure injection pump 3.

[0029] Furthermore, a first expansion valve 81 is provided between the low-pressure ejector pump 3 and the air compressor 1; a third expansion valve 83 is provided between the first evaporator 2 and the freezing chamber A. When the compressed air circulation component is working, the air compressor 1 is running, and the air branch where the first expansion valve 81 and the air branch where the third expansion valve 83 are located are both running; when the refrigeration component is working, the compressor 4 is running, the refrigerant branch where the sixth expansion valve 86 is located, the refrigerant branch where the second expansion valve 82 is located, and the refrigerant branch where the fourth expansion valve 84 is located are all running, and the inverter 6 is working.

[0030] Furthermore, a sixth expansion valve 86 is arranged between the condenser 5 and the first evaporator 2; a fourth expansion valve 84 is arranged between the condenser 5 and the second evaporator 10, the second evaporator 10 includes a second refrigeration shell 101 and a second refrigerant tube winding 102, the second refrigerant tube winding 102 is arranged in the second refrigeration shell 101, the outlet end of the condenser 5 is connected to the inlet end of the second refrigerant tube winding 102, and the outlet end of the second refrigerant tube winding 102 is connected to the inlet end of the compressor 4; a second expansion valve 82 is arranged between the condenser 5 and the inverter 6, and the first inverter inlet 65 is connected to the outlet end of the second expansion valve 82.

[0031] Furthermore, the outlet end of the air compressor 1 is connected to the air side inlet 21 on the first refrigeration shell 25, and an automatic drainer 24 connected to the first refrigeration shell 25 is arranged in front of the air side outlet 23 on the first refrigeration shell 25. The air side outlet 23 is divided into two branches, one of which is connected to the high-pressure end inlet 30 on the low-pressure ejector pump 3, and is connected to the inlet end of the air compressor 1 after passing through the ejector pump outlet 34 and the first expansion valve 81; the other branch is connected to the freezer A after passing through the third expansion valve 83, and is finally connected to the inlet end of the air compressor 1.

[0032] The working process of the above-mentioned efficient vacuum freeze-drying system includes: (I) Working process of compressed air circulation components: See also Figure 2 When the compressed air circulation component is in working state, the first expansion valve 81 and the third expansion valve 83 are both opened, and the air compressor 1 sucks in normal pressure air from the freezing chamber A for compression, and then discharges it from the air side inlet 21 into the first evaporator 2 for cooling, wherein the saturated water in the compressed air is discharged from the automatic drainer 24 in front of the air side outlet 23, and the low-temperature compressed air after dehumidification is discharged from the air side outlet 23, and then is divided into two branches, wherein the low-temperature compressed air in one branch is depressurized to normal pressure by the third expansion valve 83 and then enters the freezing chamber A to freeze and cool the items, and the normal pressure air in the freezing chamber A is discharged and then re-enters the air compressor 1 for compression, thereby realizing the circulation compression of air; see Figure 4The low-temperature compressed air in the other branch enters the low-pressure ejector pump 3 from the high-pressure end inlet 30 for high-speed injection, forming high-pressure and high-speed compressed air, and establishing a local vacuum environment in the ejector chamber 35. The air and water vapor in the cold trap cylinder 70 are sucked into the ejector chamber 35 through the first low-pressure end inlet 31 and the second low-pressure end inlet 32, and a near-vacuum environment in the vacuum drying chamber B is established and maintained. After the air and water vapor are mixed with the high-pressure and high-speed compressed air in the mixing chamber 33, they are discharged from the ejector pump outlet 34, and re-enter the air compressor 1 for compression after being reduced in pressure by the first expansion valve 81.

[0033] (II) Refrigeration component workflow: (a1) Non-defrosting operation mode: the bypass branch 12 is closed, that is, the third solenoid valve 93, the fourth solenoid valve 94, the fifth solenoid valve 95 and the sixth solenoid valve 96 are closed, and the first solenoid valve 91 and the second solenoid valve 92 are opened; the refrigerant flows through the compressor 4 and the condenser 5 in sequence and is divided into three branches: After passing through the first branch, the refrigerant passes through the sixth expansion valve 86 and enters the first refrigerant pipe winding 22 for evaporation, cooling the compressed air, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant in the second branch passes through the fourth expansion valve 84 and enters the second refrigerant pipe winding 102 in the freezing chamber A to cool the air and items in the room, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant through the third branch passes through the second expansion valve 82 and enters the first converter chamber 61 in the converter 6 from the first converter inlet 65. The refrigerant passes through the through hole 615 on the partition 614 and pushes the first slider 66 in the second converter chamber 62 and the second slider 64 in the third converter chamber 60 axially to the second converter inlet 67 and the third converter inlet 63 respectively. At this time, the first converter outlet 610 and the fourth converter outlet 69 are respectively connected to the first converter chamber 61, and the low-temperature refrigerant enters the fourth refrigerant tube winding 72 and the third refrigerant tube winding 71 in the cold trap cylinder 70 from the first converter total outlet 612 and the second converter total outlet 613 respectively to condense and capture the water vapor generated by the sublimation of the vacuum drying chamber B. Part of the water vapor generated by the sublimation of the vacuum drying chamber B is discharged simultaneously by the low-pressure ejector pump 3. The refrigerant after heat exchange enters the gas-liquid separator 11 through the first solenoid valve 91 and the second solenoid valve 92 respectively, and then returns to the compressor 4 for compression.

[0034] (a2) Defrost operation mode: ①, defrost operation mode 1: bypass branch 12 is open, that is, the second solenoid valve 92, the fifth solenoid valve 95 and the sixth solenoid valve 96 are all closed, the first solenoid valve 91, the third solenoid valve 93 and the fourth solenoid valve 94 are all opened; the refrigerant flows through the compressor 4 and the condenser 5 in sequence and is divided into three branches: among which, After passing through the first branch, the refrigerant passes through the sixth expansion valve 86 and enters the first refrigerant pipe winding 22 for evaporation, cooling the compressed air, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant in the second branch passes through the fourth expansion valve 84 and enters the second refrigerant pipe winding 102 in the freezing chamber A to cool the air and items in the room, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant through the third branch passes through the second expansion valve 82 and enters the first converter chamber 61 in the converter 6 from the first converter inlet 65. The refrigerant passes through the through hole 615 on the partition 614 and pushes the first slider 66 in the second converter chamber 62 axially to the second converter inlet 67 end. At this time, the first converter outlet 610 is connected with the first converter chamber 61. The low-temperature refrigerant enters the fourth refrigerant pipe winding 72 in the cold trap cylinder 70 from the first converter total outlet 612 to condense and capture the water vapor generated by the sublimation of the vacuum drying chamber B. Part of the water vapor generated by the sublimation of the vacuum drying chamber B is discharged at the same time by the low-pressure ejector pump 3. The refrigerant after heat exchange enters the gas-liquid separator 11 through the first solenoid valve 91 and is re-circulated. It returns to the compressor 4 for compression; in addition, the high-temperature and high-pressure refrigerant flowing through the bypass branch 12 enters the third converter chamber 60 after passing through the fourth solenoid valve 94, pushing the second slider 64 in the third converter chamber 60 axially to the end adjacent to the first converter chamber 61, and the high-temperature and high-pressure refrigerant enters the third refrigerant pipe winding 71 in the cold trap cylinder 70 from the third converter outlet 68 through the second converter total outlet 613 to release heat and defrost. The water vapor sublimated by defrosting is sucked and discharged by the first low-pressure end inlet 31 in the low-pressure ejector pump 3 to maintain a near-vacuum environment. The refrigerant after releasing heat passes through the third solenoid valve 93, is reduced in pressure by the fifth expansion valve 85, enters the gas-liquid separator 11, and then returns to the compressor 4 for compression.

[0035] ② Defrost operation mode 2: bypass branch 12 is open, that is, the first solenoid valve 91, the third solenoid valve 93 and the fourth solenoid valve 94 are all closed, and the second solenoid valve 92, the fifth solenoid valve 95 and the sixth solenoid valve 96 are all opened; the refrigerant flows through the compressor 4 and the condenser 5 in sequence and is divided into three branches: among which, After passing through the first branch, the refrigerant passes through the sixth expansion valve 86 and enters the first refrigerant pipe winding 22 for evaporation, cooling the compressed air, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant in the second branch passes through the fourth expansion valve 84 and enters the second refrigerant pipe winding 102 in the freezing chamber A to cool the air and items in the room, and then enters the gas-liquid separator 11 and returns to the compressor 4 for compression; The refrigerant through the third branch passes through the second expansion valve 82 and enters the first converter chamber 61 in the converter 6 from the first converter inlet 65. The refrigerant passes through the through hole 615 on the partition 614 and pushes the second slider 64 of the third converter chamber 60 axially to the end of the third converter inlet 63. At this time, the fourth converter outlet 69 is connected with the first converter chamber 61. The low-temperature refrigerant enters the third refrigerant pipe winding 71 in the cold trap cylinder 70 from the second converter total outlet 613 to condense and capture the water vapor generated by the sublimation of the vacuum drying chamber B. Part of the water vapor generated by the sublimation of the vacuum drying chamber B is discharged by the low-pressure ejector pump 3 at the same time. The refrigerant after heat exchange enters the gas-liquid separator 11 through the second solenoid valve 92 and then returns to Return to the compressor 4 for compression; in addition, the high-temperature and high-pressure refrigerant flowing through the bypass branch 12 enters the second converter chamber 62 after passing through the fifth solenoid valve 95, pushing the first slider 66 in the second converter chamber 62 axially to the end adjacent to the first converter chamber 61, and the high-temperature and high-pressure refrigerant enters the fourth refrigerant pipe winding 72 in the cold trap cylinder 70 from the second converter outlet 611 through the first converter total outlet 612 to release heat and defrost. The defrosted sublimated water vapor is sucked and discharged by the second low-pressure end inlet 32 ​​in the low-pressure ejector pump 3 to maintain a near-vacuum environment. The refrigerant after releasing heat passes through the sixth solenoid valve 96, is reduced in pressure by the fifth expansion valve 85, enters the gas-liquid separator 11, and then returns to the compressor 4 for compression.

[0036] Through the above settings, the high-efficiency vacuum freeze-drying system for preparing dried Chinese medicinal materials can effectively pre-dry the items in the freezer A, improve the heat exchange efficiency of the freezer A, and can effectively rotate and defrost the cold trap cylinder 70 under uninterrupted normal operation, thereby improving the overall efficiency of the vacuum freeze-drying system and significantly saving energy.

[0037] The above is a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for illustrating the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A high-efficiency vacuum freeze-drying system for preparing dry Chinese medicinal materials, characterized in that: It includes a compressed air circulation component for cooling compressed air and a refrigeration component for rotation defrosting; wherein, The compressed air circulation component comprises an air compressor (1), a first evaporator (2), and a low-pressure ejector pump (3); the air compressor (1), the first evaporator (2), and the low-pressure ejector pump (3) are connected in a closed loop along the flow direction of the working medium; the air compressor (1), the first evaporator (2), and the freezing chamber (A) are connected in a closed loop along the flow direction of the working medium; The refrigeration assembly comprises a compressor (4), a condenser (5), an inverter (6), a second evaporator (10) and a cold trap (7); the compressor (4), the condenser (5) and the first evaporator (2) are connected in a closed loop along the flow direction of the refrigerant; the compressor (4), the condenser (5) and the second evaporator (10) are connected in a closed loop along the flow direction of the refrigerant; the compressor (4), the condenser (5), the inverter (6) and the cold trap (7) are connected in a closed loop along the flow direction of the refrigerant; the compressor (4), the inverter (6) and the cold trap (7) are connected in a closed loop along the flow direction of the refrigerant; the low-pressure ejector pump (3) is connected to the cold trap (7); the second evaporator (10) is arranged in a freezing chamber (A), and the cold trap (7) is arranged in a vacuum drying chamber (B).

2. The high-efficiency vacuum freeze-drying system according to claim 1, characterized in that: The inverter (6) comprises a first inverter inlet (65) connected to the condenser (5), a second inverter inlet (67) connected to the compressor (4), a third inverter inlet (63) connected to the compressor (4), a first inverter outlet (612), a second inverter outlet (613) and an inverter assembly; the cold trap (7) comprises a third refrigerant tube winding (71) for implementing a first defrosting operation mode, and a fourth refrigerant tube winding (72) for implementing a second defrosting operation mode; the first inverter outlet (612) is connected to the fourth refrigerant tube winding (72), and the second inverter outlet (613) is connected to the third refrigerant tube winding (71); in a refrigeration operation mode, the inverter assembly regulates the first inverter inlet (65) to be connected to the first inverter outlet (612) and the second inverter outlet (613) respectively; in a defrosting operation mode, the inverter assembly regulates the second inverter inlet (67) to be connected to the first inverter outlet (612), and the third inverter inlet (63) to be connected to the second inverter outlet (613).

3. The high-efficiency vacuum freeze-drying system according to claim 2, characterized in that: The commutation assembly comprises a first commutation chamber (61), a second commutation chamber (62) and a third commutation chamber (60); the first commutation chamber (61) is connected to the second commutation chamber (62) and the third commutation chamber (60), respectively; the first commutation inlet (65) is connected to the first commutation chamber (61), the second commutation inlet (67) is connected to the second commutation chamber (62), and the third commutation inlet (63) is connected to the third commutation chamber (60); a first slider (66) is slidably arranged in the second commutation chamber (62), and a first commutation outlet (610) and a second commutation outlet (611) respectively connected to the first commutation main outlet (612) are arranged on the second commutation chamber (62); when the first slider (66) slides to the first When the first slider (66) slides to the second working position, the first converter inlet (65) is connected to the first converter outlet (610); when the first slider (66) slides to the second working position, the second converter inlet (67) is connected to the second converter outlet (611); a second slider (64) is slidably arranged in the third converter chamber (60); a third converter outlet (68) and a fourth converter outlet (69) respectively connected to the second converter main outlet (613) are arranged on the third converter chamber (60); when the second slider (64) slides to the first working position, the first converter inlet (65) is connected to the fourth converter outlet (69); when the second slider (64) slides to the second working position, the third converter inlet (63) is connected to the third converter outlet (68).

4. The high-efficiency vacuum freeze-drying system according to claim 3, characterized in that: The cold trap device (7) comprises a cold trap cylinder (70) and an insulating partition (73), wherein the insulating partition (73) divides the inner cavity of the cold trap cylinder (70) into an outer trap chamber (74) and an inner trap chamber (75), wherein the third refrigerant tube winding (71) is arranged in the outer trap chamber (74), and the fourth refrigerant tube winding (72) is arranged in the inner trap chamber (75); the outer trap chamber (74) and the inner trap chamber (75) are respectively connected to a low-pressure ejector pump (3).

5. The high-efficiency vacuum freeze-drying system according to claim 4, characterized in that: The low-pressure ejector pump (3) comprises a high-pressure end inlet (30), an ejector chamber (35), a mixing chamber (33), and an ejector pump outlet (34) which are sequentially connected along the flow direction of the working medium; the first evaporator (2) is connected to the high-pressure end inlet (30), and the ejector pump outlet (34) is connected to the air compressor (1); and the outer trap chamber (74) and the inner trap chamber (75) are respectively connected to the ejector chamber (35).

6. The high-efficiency vacuum freeze-drying system according to claim 4, characterized in that: A control component is provided between the cold trap (7) and the compressor (4), and the control component comprises a first solenoid valve (91), a second solenoid valve (92), a third solenoid valve (93), a sixth solenoid valve (96) and a fifth expansion valve (85); the first solenoid valve (91) and the sixth solenoid valve (96) are connected in parallel between the fourth refrigerant pipe winding (72) and the compressor (4), and the second solenoid valve (92) and the third solenoid valve (93) are connected in parallel between the third refrigerant pipe winding (71) and the compressor (4); and the fifth expansion valve (85) is connected in series with the third solenoid valve (93) and the sixth solenoid valve (96), respectively.

7. The high-efficiency vacuum freeze-drying system according to claim 1, characterized in that: The first evaporator (2) comprises a first refrigerant tube winding (22) and a first refrigeration shell (25), wherein the first refrigerant tube winding (22) is arranged in the first refrigeration shell (25); the inlet end of the first refrigerant tube winding (22) is connected to the condenser (5), and the outlet end of the first refrigerant tube winding (22) is connected to the compressor (4); the inlet end of the first refrigeration shell (25) is connected to the air compressor (1), and the outlet end of the first refrigeration shell (25) is connected to the low-pressure ejector pump (3).

8. The high-efficiency vacuum freeze-drying system according to claim 1, characterized in that: A first expansion valve (81) is provided between the low-pressure ejector pump (3) and the air compressor (1); and a third expansion valve (83) is provided between the first evaporator (2) and the freezing chamber (A).

9. The high-efficiency vacuum freeze-drying system according to claim 1, characterized in that: A sixth expansion valve (86) is provided between the condenser (5) and the first evaporator (2); a fourth expansion valve (84) is provided between the condenser (5) and the second evaporator (10); and a second expansion valve (82) is provided between the condenser (5) and the inverter (6).

10. The working process of the high-efficiency vacuum freeze-drying system according to any one of claims 1 to 9, characterized in that: include, (I) Working process of compressed air circulation components: The air compressor (1) sucks in atmospheric pressure air from the freezing chamber (A) for compression and then discharges it into the first evaporator (2) for cooling and dehumidification. After dehumidification, the low-temperature compressed air is discharged from the first evaporator (2); part of the low-temperature compressed air is reduced in pressure to atmospheric pressure and then enters the freezing chamber (A) to freeze and cool items. The atmospheric pressure air in the freezing chamber (A) is discharged and then re-enters the air compressor (1) for compression, thereby achieving air circulation compression; part of the low-temperature compressed air enters the low-pressure ejector pump (3) for high-speed injection to form high-pressure and high-speed compressed air. A local vacuum environment is established inside the low-pressure ejector pump (3) to suck in air and water vapor in the cold trap (7). The air and water vapor are mixed with the high-pressure and high-speed compressed air and then reduced in pressure and re-enter the air compressor (1) for compression; (II) Refrigeration component workflow: (a1) Non-defrosting operation mode: The refrigerant flows through the compressor (4) and the condenser (5) in sequence and is divided into three branches: The refrigerant passing through the first branch enters the first evaporator (2) to evaporate, cools the compressed air, and then returns to the compressor (4) to be compressed; The refrigerant passing through the second branch enters the second evaporator (10) to cool the air and items in the freezing chamber (A), and then returns to the compressor (4) for compression; The refrigerant through the third branch enters the inverter (6), and then enters the cold trap (7) to condense and capture the water vapor generated by sublimation in the vacuum drying chamber (B). Part of the water vapor generated by sublimation in the vacuum drying chamber (B) is discharged by the low-pressure ejector pump (3), and the refrigerant after heat exchange is returned to the compressor (4) for compression; (a2) Defrost operation mode: ①. Defrost operation mode 1: The refrigerant flows through the compressor (4) and the condenser (5) in sequence and is divided into three branches: The refrigerant passing through the first branch enters the first evaporator (2) to evaporate, cools the compressed air, and then returns to the compressor (4) to be compressed; The refrigerant passing through the second branch enters the second evaporator (10) to cool the air and items in the freezing chamber (A), and then returns to the compressor (4) for compression; The refrigerant through the third branch enters the inverter (6), and the low-temperature refrigerant enters the cold trap (7) to condense and capture the water vapor generated by sublimation in the vacuum drying chamber (B). Part of the water vapor generated by sublimation in the vacuum drying chamber (B) is discharged by the low-pressure ejector pump (3), and the refrigerant after heat exchange returns to the compressor (4) for compression; in addition, the high-temperature and high-pressure refrigerant enters the inverter (6), and the high-temperature and high-pressure refrigerant enters the cold trap (7) for heat release and defrosting. The water vapor sublimated by defrosting is sucked and discharged by the low-pressure ejector pump (3), and the refrigerant after heat release returns to the compressor (4) for compression after pressure reduction; ② Defrost operation mode 2: The refrigerant flows through the compressor (4) and the condenser (5) in sequence and is divided into three branches: The refrigerant passing through the first branch enters the first evaporator (2) to evaporate, cools the compressed air, and then returns to the compressor (4) to be compressed; The refrigerant passing through the second branch enters the second evaporator (10) to cool the air and items in the freezing chamber (A), and then returns to the compressor (4) for compression; The refrigerant through the third branch enters the inverter (6), and the low-temperature refrigerant enters the cold trap (7) to condense and capture the water vapor generated by sublimation in the vacuum drying chamber (B). Part of the water vapor generated by sublimation in the vacuum drying chamber (B) is discharged by the low-pressure ejector pump (3), and the refrigerant after heat exchange returns to the compressor (4) for compression; in addition, the high-temperature and high-pressure refrigerant enters the inverter (6), and the high-temperature and high-pressure refrigerant enters the cold trap (7) for heat release and defrosting. The water vapor sublimated by defrosting is sucked and discharged by the low-pressure ejector pump (3), and the refrigerant after heat release returns to the compressor (4) for compression after pressure reduction.

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