Energy-saving multifunctional ultralow-temperature microwave vacuum continuous freeze-drying equipment and freeze-drying method

Abstract

The invention discloses energy-saving multifunctional ultralow-temperature microwave vacuum continuous freeze-drying equipment which comprises a cavity and a vacuum unit, and the vacuum unit is communicated with the cavity. A plurality of belt conveying mechanisms are arranged in the cavity, and a plurality of side-by-side supporting plates are arranged below conveying belts of the belt conveying mechanisms; wherein the cold trap is communicated with the cavity, and the vacuum unit is communicated with the cavity through the cold trap; part of the supporting plate at the input end of the belt conveying mechanism is replaced by a refrigerating plate, and refrigerating fluid is introduced into the refrigerating plate. The invention further discloses a freeze-drying method which is applied to the energy-saving multifunctional ultralow-temperature microwave vacuum continuous freeze-drying equipment in the previous embodiment. The problems that existing freeze-drying equipment is long in cooling time and large in energy consumption, and part of the freeze-drying equipment is single in function are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave low-temperature vacuum drying equipment, and particularly relates to an energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment and a freeze-drying method. Background Art

[0002] Vacuum freeze-drying (hereinafter referred to as freeze-drying) is carried out at a temperature below zero degrees Celsius, even as low as minus 60 to 70 degrees Celsius, and under the conditions of vacuum and lack of oxygen. During the drying process, the chemical and biochemical reactions in the processed material (hereinafter referred to as the material) can be minimized; the volatilization of its components can be reduced; and there is basically no shrinkage or deformation after drying. Compared with ordinary drying methods, the original shape and components of the material can be well maintained. Currently, freeze-drying is mainly applied to the fields of medicine, food, biology, chemical industry, etc.

[0003] In the prior art, the material is first frozen to a specified temperature by setting a freeze-drying chamber or a freeze-drying room, and then the material is heated to cause the material to sublimate, and the sublimated water vapor is extracted and discharged as a liquid through a water capture device. However, due to the large volume of the cooling chamber, it takes a long time to cool the entire cooling chamber to minus 60 to 70 degrees Celsius.

[0004] The Chinese patent document with the patent publication number CN119075324A discloses a microwave vacuum low-temperature liquid continuous belt dryer, which includes: a concentration device, a main machine device, a feeding device, a collecting device, a packaging device, a vacuum unit and a cold water device; wherein, the liquid product is preliminarily evaporated through the concentration device; the main machine device includes a cavity and a number of belt conveying modules; a number of groups of first microwave generators are arranged on the cavity; the feeding device is respectively connected to the concentration device and a number of belt conveying modules; the collecting device is connected to a number of belt conveying modules; the packaging device is connected to the collecting device; the vacuum port of the vacuum unit is respectively connected to the top and both sides of the cavity through a number of vacuum pipes; the cooling water pipe of the cold water device is connected to the first microwave generator, and the cold water device is used to cool the first microwave generator and its microwave power supply. The invention has a high degree of automation, high efficiency and can operate continuously for a long time. However, because it does not integrate freeze-drying technology, it can only achieve the drying function above zero degrees Celsius, cannot meet the special requirements of freeze-drying operations at sub-zero temperatures, and is difficult to fill the demand gap for high-efficiency continuous freeze-drying equipment in the market. In addition, although two sets of water capture devices are also used in this patent, when they work alternately, one of them is in a completely stopped state and cannot continue to complete the water capture function, which also greatly wastes electric energy. Summary of the Invention

[0005] According to an embodiment of the present invention, an energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying device is provided, which includes a cavity and a vacuum unit. The vacuum unit is connected to the cavity; several belt conveying mechanisms are arranged in the cavity, and a plurality of parallel support plates are arranged below the conveying belt of the belt conveying mechanism. The device further includes: A cold trap, the cold trap is connected to the cavity, and the vacuum unit is connected to the cavity through the cold trap; Part of the support plates at the input end of the belt conveying mechanism are replaced by refrigeration plates, and a refrigerant is introduced into the refrigeration plates.

[0006] Furthermore, the cold trap includes: a first housing, a first coil group, a second coil group, a second housing, and a third housing; The second housing and the third housing are arranged side by side in the first housing, and the bottoms of the second housing and the third housing are connected; The first coil group is arranged in the second housing; The second coil group is arranged in the third housing; A plurality of cooling fins are arranged on both the first coil group and the second coil group; Refrigerants are respectively introduced into the first coil group and the second coil group.

[0007] Furthermore, A first communication port is arranged at the top of the second housing, and a second communication port is arranged on one side of the top of the third housing; The first communication port is connected to the cavity, and the second communication port is connected to the vacuum unit.

[0008] Furthermore, the device further includes: a first shunt pipe; The first shunt pipe is arranged in the second housing and horizontally arranged on the top of the first coil group. The upper end is connected to the first communication port, and a plurality of shunt holes are arranged at the lower end.

[0009] Furthermore, the device further includes: a second shunt pipe; The second shunt pipe is arranged in the third housing and horizontally arranged on the top of the second coil group. One side is connected to the first communication port, and a plurality of shunt holes are arranged at the lower end.

[0010] Furthermore, an observation window is arranged on one side of the first housing, and the internal situation of the first housing can be observed through the observation window.

[0011] Furthermore, the refrigerant is Freon or liquid nitrogen.

[0012] Furthermore, a serpentine flow channel is arranged in the refrigeration plate, and the refrigerant enters the serpentine flow channel from one end of the refrigeration plate and flows out of the serpentine flow channel from the other end of the refrigeration plate.

[0013] Furthermore, the material of the conveying belt is cis-1,4-polybutadiene rubber or silicone rubber.

[0014] According to another embodiment of the present invention, a freeze-drying method is provided, which is applied to the energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment of the previous embodiment. In this method, a plurality of cooling plates are arranged under the conveying belt at the input end of the belt conveyor, and local refrigeration is achieved by using the cooling plates. A cold trap is arranged between the cavity and the vacuum unit, and two sets of water capture systems are arranged in the cold trap. The bottoms of the two sets of water capture systems are connected. During operation, the water vapor in the cavity passes through the two sets of water capture systems in sequence. Freon or liquid nitrogen is used as the refrigerant.

[0015] Advantages of the present invention: 1. Energy-saving and efficient: By using a refrigeration plate at the input end of the belt conveying mechanism to achieve local refrigeration, the temperature of the material on the conveying belt can be quickly reduced to the set temperature, avoiding cooling the entire cooling chamber, greatly shortening the cooling time, and reducing energy consumption.

[0016] 2. Continuous operation: Two sets of water capture systems (i.e., the first coil group and the second coil group) are arranged in the cold trap. One set captures water and the other defrosts, working alternately. The defrosting water capture system can still retain the water vapor in the gas due to its low temperature, effectively solving the problem of energy waste of the existing water capture device.

[0017] 3. Multi-functional ultra-low temperature freeze-drying: Combining technologies such as microwave and low vacuum, it can achieve continuous freeze-drying of materials in an ultra-low temperature environment, enabling a set of drying equipment to have two drying functions: above-zero low-temperature drying and freeze-drying.

[0018] 4. Dual cooling: First, the refrigeration plate quickly cools the material, and then the evaporated water vapor is collected by the vacuum unit and the cold trap to further reduce the temperature in the cavity, enabling the belt conveying mechanism to operate continuously at a faster speed, greatly improving production efficiency.

[0019] It should be understood that both the foregoing general description and the following detailed description are exemplary and are intended to provide further explanation of the claimed technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a perspective view according to an embodiment of the present invention; Figure 2 is Figure 1 the top view of; Figure 3 is Figure 2 the sectional view taken along the line A-A of; Figure 4 is Figure 3 the enlarged view at A of; Figure 5 is Figure 2 the sectional view taken along the line B-B of; Figure 6 This is a schematic diagram of the structure of the auxiliary machine part (including a cold trap, a vacuum unit, etc.) according to an embodiment of the present invention; Figure 7 for Figure 6 A top view of Figure 8 for Figure 7 CC section view; Figure 9 is a schematic structural diagram of a cold trap according to an embodiment of the present invention; Figure 10 for Figure 9 Left view of Figure 11 for Figure 10 Enlarged view of DD; Figure 12 A schematic diagram of the internal structure of a cold trap according to an embodiment of the present invention; Figure 13 It is a schematic diagram of the structure of the refrigeration plate with the upper cover removed according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings to further illustrate the present invention.

[0022] First, combine Figures 1 to 13 The energy-saving and multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to the embodiment of the present invention is described, which is used in the fields of medicine, food, biology, chemical industry, etc. and has a wide range of application scenarios.

[0023] like Figures 1 to 13 As shown, the energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment of the embodiment of the present invention comprises a cavity 1 and a vacuum unit 2, the vacuum unit 2 is connected to the cavity 1; a plurality of belt conveyor mechanisms 11 are arranged in the cavity 1, and a plurality of support plates arranged side by side are arranged under the conveyor belt of the belt conveyor mechanism 11, and further comprises: A cold trap 3, the cold trap 3 is connected to the cavity 1, and the vacuum unit 2 is connected to the cavity 1 through the cold trap 3; Part of the support plates at the input end of the belt conveyor mechanism 11 is replaced by a refrigeration plate 4, the interior of the refrigeration plate 4 is hollow, and a refrigerant is passed into the refrigeration plate 4; the number of refrigeration plates 4 can be selected according to demand, and the refrigeration plates 4 are arranged in sequence under the conveyor belt, which can not only freeze the materials on the conveyor belt, but also replace the support plate to support the conveyor belt.

[0024] Further, if Figure 8 , 12 As shown, in this embodiment, the cold trap 3 comprises: a first shell 31, a first coil group 32, a second coil group 33, a second shell 35 and a third shell 36; The second housing 35 and the third housing 36 are arranged side by side within the first housing 31, and the bottoms of the second housing 35 and the third housing 36 are in communication; The first coil group 32 is disposed within the second housing 35; The second coil group 33 is disposed within the third housing 36; A plurality of cooling fins 34 are provided on both the first coil group 32 and the second coil group 33; Refrigerant is respectively introduced into the first coil group 32 and the second coil group 33.

[0025] The cold trap 3 is divided into two sets of water capture systems. The two sets of water capture systems are separately introduced with refrigerant and can operate alternately, one for water capture and one for defrosting, greatly improving the working efficiency. In addition, the vacuum unit 2 extracts the gas in the cavity 1, which successively passes through the second housing 35 and the third housing 36, contacts the first coil, the second coil, and the third coil, and then condenses or even frosts; in this way, even when one set of water capture system is in the defrosting state, a relatively low temperature can still be maintained, and the passing water vapor can still be condensed. In the prior art, when one set of water capture system stops, the intake valve is closed, and the water vapor will flow in the same direction to the other set of water capture system, thus greatly wasting energy.

[0026] Preferably, as Figure 8 shown, in this embodiment, a drain pipe (prior art) is provided at the bottom of the first housing 31, and the bottom of the first housing 31 is in communication with the bottoms of the second housing 35 and the third housing 36.

[0027] Further, as Figure 8 shown, in this embodiment, the second housing 35 and the third housing 36 are sealed housings, sealing the corresponding first coil group 32 and second coil group 33.

[0028] Further, as Figure 8 、 9 shown, in this embodiment, a first communication port 311 is provided at the top of the second housing 35, and a second communication port 312 is provided on one side of the top of the third housing 36; the first communication port 311 is in communication with the cavity 1, and the second communication port 312 is in communication with the vacuum unit 2.

[0029] The gas in the cavity 1 enters from the top of the second housing 35 through the first communication port 311 until it reaches the bottom. During this process, part of the water vapor condenses or frosts. Then, the remaining water vapor enters from the bottom of the third housing 36 for condensation or frosting. At this time, the moisture in the air is almost zero, and the remaining gas is discharged from the second communication port 312 into the vacuum unit 2; the second communication port 312 is provided on one side, changing the flow direction of the gas, increasing the time for the gas to stay in the third housing 36, and further improving the water capture efficiency.

[0030] Further, as Figure 8, 12 As shown, in this embodiment, it further includes: a first shunt pipe 37; The first shunt pipe 37 is arranged in the second housing 35 and horizontally placed on the top of the first coil group 32. Its upper end is connected to the first communication port 311, and several shunt holes 371 are provided at its lower end. The gas in the cavity 1 is shunted through the several shunt holes 371 and evenly enters the second housing 35, making the water capture efficiency of the second coil group 33 and the fins 34 higher.

[0031] Furthermore, as Figure 8 , 12 shown, in this embodiment, it further includes: a second shunt pipe 38; The second shunt pipe 38 is arranged in the third housing 36 and horizontally placed on the top of the second coil group 33. One side of it is connected to the first communication port 311, and several shunt holes 381 are provided at its lower end. The remaining gas enters the second shunt pipe 38 from the shunt holes 381 and is then discharged through the second communication port 312, which is convenient for improving the water capture efficiency.

[0032] Preferably, as Figure 8 , 12 shown, in this embodiment, the diameter of the second shunt pipe 38 is smaller than that of the first shunt pipe 37, which is convenient for further improving the water capture efficiency.

[0033] Furthermore, as Figure 6 , 9 shown, in this embodiment, an observation window 313 is provided on one side of the first housing 31. The observation window 313 is sealed with quartz glass, and the internal situation of the first housing 31 can be observed through the observation window 313.

[0034] Furthermore, in this embodiment, the refrigerant is Freon or liquid nitrogen, and the refrigeration effect is good. The lowest evaporation temperature that Freon can achieve is up to -120°C; the temperature of the liquid nitrogen cold trap 3 is usually around -196°C. However, in actual applications, according to specific designs and requirements, its temperature setting range can be from normal temperature to -196°C or even lower.

[0035] Furthermore, as Figure 13 shown, in this embodiment, a serpentine flow channel 41 is provided in the refrigeration plate 4. The refrigerant enters the serpentine flow channel 41 from one end of the cooling plate and flows out of the serpentine flow channel 41 from the other end of the cooling plate. The serpentine channel greatly improves the refrigeration effect.

[0036] Furthermore, as Figures 3 to 4 shown, in this embodiment, the material of the conveyor belt is cis-1,4-polybutadiene rubber or silicone rubber, which can maintain good stability at ultra-low temperatures.

[0037] According to another embodiment of the present invention, a freeze-drying method is provided, which is applied to the energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment of the previous embodiment. In this method, a plurality of cooling plates are arranged under the conveyor belt at the input end of the belt conveyor, and local refrigeration is achieved by using the cooling plates. A cold trap 3 is arranged between the cavity 1 and the vacuum unit 2. Two water capture systems are arranged in the cold trap 3, and the bottoms of the two water capture systems are connected. During operation, the water vapor in the cavity 1 passes through the two water capture systems in sequence. One of the two water capture systems captures water, and the other defrosts; it is also possible to capture water simultaneously first, and then defrost one of them first, which is selected according to specific requirements and the cooling stage. Freon or liquid nitrogen is used as the refrigerant, which has good refrigeration effect and fast speed.

[0038] Working principle: The vacuum unit 2 works to evacuate the cavity 1 into a vacuum. At the same time, the cold trap 3 works, and the external refrigerant is introduced into the cooling plates through pipelines. Then, the material (taking liquid material as an example) is conveyed by the feeding device to the input end of the belt conveying mechanism 11. After the refrigeration plate 4 at the input end freezes the material to the specified temperature, the belt conveyor moves, and the microwave generator emits microwaves to sublime the moisture in the material. The sublimated gas is pumped out by the vacuum unit 2 and captured by the cold trap 3 for water capture; after a certain period of time, the belt conveying mechanism 11 continues to convey the freeze-dried material forward to the cooling plate at the output end of the belt conveyor (which is a prior art, for details, see the Chinese patent document with the patent publication number CN119075324A) to be cooled and then sent out of the cavity 1. During this period, the belt conveyor can convey the material step by step or slowly and continuously, depending on the actual requirements.

[0039] When the material does not need to be freeze-dried and only needs low-temperature drying at above-zero temperature, the refrigerant can be stopped from being conveyed into the refrigeration plate 4, so that low-temperature drying can be directly carried out like a microwave vacuum low-temperature liquid continuous belt dryer disclosed in the publication number CN119075324A.

[0040] As above, with reference to Figures 1 to 13 The energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment and freeze-drying method according to the embodiments of the present invention are described, which solve the problems of long cooling time, high energy consumption of existing freeze-drying equipment, and single function of some drying equipment.

[0041] It should be noted that in this specification, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, elements defined by the statement "comprising..." do not preclude the presence of additional identical elements in the process, method, article or device comprising the elements.

[0042] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. After those skilled in the art have read the above content, various modifications and alternatives to the present invention will be obvious. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims

1. An energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying device, comprising a cavity and a vacuum unit, the vacuum unit being connected to the cavity; a plurality of belt conveying mechanisms are arranged in the cavity, and a plurality of side-by-side support plates are arranged below the conveying belt of the belt conveying mechanism, characterized in that, It also includes: A cold trap, which is communicated with the cavity, and the vacuum unit is communicated with the cavity through the cold trap; Part of the support plate at the input end of the belt conveying mechanism is replaced by a refrigeration plate, and a refrigerant is introduced into the refrigeration plate.

2. The energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 1, characterized in that, The cold trap includes: a first housing, a first coil group, a second coil group, a second housing and a third housing; The second housing and the third housing are arranged side by side in the first housing, and the bottoms of the second housing and the third housing are communicated; The first coil group is arranged in the second housing; The second coil group is arranged in the third housing; A number of cooling fins are arranged on both the first coil group and the second coil group; Refrigerants are respectively introduced into the first coil group and the second coil group.

3. The energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 2, wherein A first communication port is arranged at the top of the second housing, and a second communication port is arranged at one side of the top of the third housing; The first communication port is communicated with the cavity, and the second communication port is communicated with the vacuum unit.

4. The energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 3, characterized in that, It also includes: a first shunt pipe; The first shunt pipe is arranged in the second housing and is horizontally arranged on the top of the first coil group, with the upper end communicated with the first communication port and a number of shunt holes arranged at the lower end.

5. The energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 3, characterized in that, It also includes: a second shunt pipe; The second shunt pipe is arranged in the third housing and is horizontally arranged on the top of the second coil group, with one side communicated with the first communication port and a number of shunt holes arranged at the lower end.

6. The energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 2, characterized in that, An observation window is arranged on one side of the first housing, and the internal situation of the first housing can be observed according to the observation window.

7. The energy-saving multi-functional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 2, characterized in that, The refrigerant is Freon or liquid nitrogen.

8. The energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 1, characterized in that, A serpentine flow channel is arranged in the refrigeration plate, and the refrigerant enters the serpentine flow channel from one end of the refrigeration plate and flows out of the serpentine flow channel from the other end of the refrigeration plate.

9. The energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to claim 1, characterized in that, The material of the conveying belt is cis-butadiene rubber or silicone rubber.

10. A freeze-drying method, which is applied to the energy-saving multifunctional ultra-low temperature microwave vacuum continuous freeze-drying equipment according to any one of claims 1 to 9, wherein A number of refrigeration plates are arranged below the conveying belt at the input end of the belt conveyor, and local refrigeration is realized by using the refrigeration plates; A cold trap is arranged between the cavity and the vacuum unit, and two water capture systems are arranged in the cold trap, and the bottoms of the two water capture systems are communicated. During operation, the water vapor in the cavity passes through the two water capture systems in sequence; Freon or liquid nitrogen is used as the refrigerant.

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