Multi-cold-trap freeze-drying device based on dynamic weighing and method thereof

Abstract

The invention relates to the technical field of freeze-drying, in particular to a multi-cold-trap freeze-drying device based on dynamic weighing and a method of the multi-cold-trap freeze-drying device. According to the multi-cold-trap freeze-drying device based on dynamic weighing, the multiple cold traps are connected to the drying body, the vacuum mechanism and the water storage mechanism are connected to the multiple cold traps, the heating mechanism is connected to the water storage mechanism, and the control mechanism is electrically connected with the water storage mechanism, the heating mechanism and the vacuum mechanism. The control mechanism is used for controlling the working states of the water storage mechanism, the heating mechanism and the vacuum mechanism, so that alternate uninterrupted drying of multiple cold traps can be realized, and the drying efficiency is effectively improved; and the freeze-drying end point is judged by utilizing a dynamic weighing method, so that the accurate judgment of the drying end point is realized.

Description

Technical Field

[0001] The invention relates to the technical field of freeze drying, and in particular to a multi-cold-trap freeze drying device based on dynamic weighing and a method thereof. Background Art

[0002] The freeze dryer (hereinafter referred to as "freeze dryer") is mainly composed of four core components: refrigerator, drying chamber, cold trap, and vacuum pump. The cold trap is one of the four core components of the freeze dryer, and its function is to condense the solvent (gas) sublimated from the compound. At present, most compounds (infinitely close to 100%) cannot sublimate under natural conditions. Therefore, this means that the cold trap and drying chamber in the freeze drying process must be sealed in a vacuum environment provided by a vacuum pump.

[0003] The sealing status of the freeze dryer is as follows: Figure 1 As shown: 2 is the drying chamber, 3 is the cold trap, and 4 is the vacuum pump. Before the freeze-drying process is completed, the drying chamber cannot be separated from the sealing system. The pressure rise method and the weighing method are often used to determine the freeze-drying endpoint (when the freeze-drying process is completed) in a sealed environment. The pressure rise method, whether it is the isochronous pressure difference method or the isobaric time difference method, is based on the characteristics of the sample (compound) and the accuracy of the equipment sensor. Even the automatic pressure rise test program can reduce certain operating errors, but for samples with extreme dryness and samples with a tighter molecular structure, there are still large errors.

[0004] The weighing method is to set a fixed position on the sample layer plate of the drying chamber, and weigh the sample at the fixed position under atmospheric pressure, for example: the mass of the sample container M v . Sample solute mass M s , the total mass in the initial state is M 0 , water content X (solute mass M s , total mass M 0 One of the three factors, X and water content, should be known. The following formula is simplified and directly uses M s Calculation). When the moisture content is required to be dried to 1%, set the reading mass to M e If the standard is met, the formula can be used to calculate: M e =M s / (1-1%)+M v However, this weighing method requires the sample to be weighed in a natural environment, and the natural environment is not completely equal to the standard (ideal) atmospheric pressure. The temperature sensor cannot self-adjust and calibrate each time it is weighed online. Therefore, this method will also lead to large weighing errors.

[0005] At present, freeze-drying equipment is classified into different categories, from preparation equipment, pilot equipment, and production equipment. The drying scale is fixed, for example, a 500kG production freeze-dryer has a total batch freeze-drying output of 500kG. And for pharmaceutical production freeze-drying, the product volume must reach 90% of the total output, otherwise it will affect the overall use.

[0006] For the ODM industry, as well as in the fields of synthetic biology, biological cytology, and genetics, even for multi-variety fruit and food processing companies, the batch size will present a completely different situation. For example, the output of matcha-like colors of a well-known food pigment company is 120 tons, while the sales volume of yellow peach-like colors is average, with an annual output of only 0.5 tons. Currently, 500kG-level freeze-drying production is used, which requires 240 batches of matcha-like colors per year. In order to meet production requirements, companies usually purchase freeze-drying equipment with different production capacities. However, any freeze-drying equipment needs to clean the entire cavity online when changing samples to avoid cross contamination. Online cleaning increases the time for converting production energy. Therefore, this causes problems such as low production efficiency, high cost, and large errors in products after drying.

[0007] In view of this, the present application proposes a multi-cold-trap freeze-drying device based on dynamic weighing and a method thereof to solve the above-mentioned problems. Summary of the invention

[0008] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a multi-cold-trap freeze-drying device based on dynamic weighing and a method thereof.

[0009] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: a multi-cold-trap freeze-drying device based on dynamic weighing, comprising a control mechanism, a drying body provided with a drying chamber, a plurality of cold traps connected to the drying body, a vacuum mechanism and a water storage mechanism connected to the plurality of cold traps, a heating mechanism connected to the water storage mechanism, the control mechanism being electrically connected to the water storage mechanism, the heating mechanism and the vacuum mechanism, and being used to control the working states of the water storage mechanism, the heating mechanism and the vacuum mechanism.

[0010] Furthermore, a plurality of the cold traps are interconnected via tracks to form a ring structure.

[0011] Furthermore, a first valve electrically connected to the control mechanism is installed between the cold trap and the drying body.

[0012] Furthermore, the vacuum mechanism comprises a vacuum pump, and a second valve electrically connected to the control mechanism is installed at the output end of the vacuum pump.

[0013] Furthermore, the water storage mechanism includes a water reservoir, and a third valve electrically connected to the control mechanism is installed between the water inlet end of the water reservoir and the cold trap.

[0014] Furthermore, a fourth valve electrically connected to the control mechanism is provided at the water outlet of the water reservoir.

[0015] Furthermore, a liquid level detector is installed in the water storage tank, and the liquid level detector is electrically connected to the control mechanism.

[0016] Furthermore, the control mechanism includes a controller, and the controller includes one or more of Liona, YULIA, and Sagitta.

[0017] A multi-cold-trap freeze-drying method based on dynamic weighing, using the above-mentioned multi-cold-trap freeze-drying method, the method is as follows:

[0018] S1. Place the product to be dried into the freeze-drying chamber;

[0019] S2, start the first valve between the first cold trap and the vacuum pump and the second valve between the vacuum pump and the first cold trap, and after the first valve and the second valve have been running for a period of time, start the second cold trap and close the first valve and the second valve;

[0020] S3. When the first valve and the second valve are opened again, the second valve of the second cold trap will be closed for 3 seconds, and the first valve of the second cold trap will be closed for 3 seconds after the second valve of the second cold trap is closed.

[0021] Furthermore, it also includes a thawing process, which includes closing the first valve for 10 seconds, opening the third valve, returning the water in the cold trap to the water storage tank, and closing the fourth valve. When the water level reaches the restricted area, the third valve is closed and the fourth valve is opened.

[0022] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0023] The present application connects a plurality of cold traps to a drying body, a vacuum mechanism and a water storage mechanism are connected to the plurality of cold traps, a heating mechanism is connected to the water storage mechanism, and the control mechanism is electrically connected to the water storage mechanism, the heating mechanism and the vacuum mechanism to control the working states of the water storage mechanism, the heating mechanism and the vacuum mechanism, thereby realizing alternating and uninterrupted drying of multiple cold traps and effectively improving the drying efficiency; and the dynamic weighing method is used to determine the freeze-drying endpoint, thereby realizing accurate determination of the drying endpoint. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the background technology;

[0025] Figure 2 It is a structural schematic diagram of a multi-cold-trap freeze-drying device based on dynamic weighing in a preferred embodiment of the present invention;

[0026] Figure 3Schematic diagram of the control structure of a multi-cold-trap freeze-drying device based on dynamic weighing in a preferred embodiment of the present invention.

[0027] Figure numerals: 1. control mechanism; 2. drying body; 3. cold trap; 4. vacuum mechanism; 5. water storage mechanism; 6. heating mechanism; 7. first valve; 8. second valve; 9. third valve; 10. fourth valve. DETAILED DESCRIPTION

[0028] The technical solutions in the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0029] Reference Figure 1-Figure 3 As shown, a preferred embodiment of the present invention is a multi-cold-trap freeze-drying device based on dynamic weighing, comprising a control mechanism 1, a drying body 2 provided with a drying chamber, the drying body 2 is connected to a plurality of cold traps 3, a plurality of the cold traps 3 are connected to a vacuum mechanism 4 and a water storage mechanism 5, the water storage mechanism 5 is connected to a heating mechanism 6, the control mechanism 1 is electrically connected to the water storage mechanism 5, the heating mechanism 6, and the vacuum mechanism 4, and is used to control the working states of the water storage mechanism 5, the heating mechanism 6, and the vacuum mechanism 4, so as to realize alternating and uninterrupted drying of multiple cold traps and effectively improve the drying efficiency; and the dynamic weighing method is used to judge the freeze-drying end point, so as to realize the accurate judgment of the drying end point.

[0030] As a preferred embodiment of the present invention, it may also have the following additional technical features: a plurality of the cold traps 3 are connected to each other through a track to form a ring structure, thereby facilitating the drying body to select a corresponding cold trap for freeze drying of the product.

[0031] In this embodiment, a first valve 7 electrically connected to the control mechanism 1 is installed between the cold trap 3 and the drying body 2; and the vacuum mechanism 4 includes a vacuum pump, and a second valve 8 electrically connected to the control mechanism is installed at the output end of the vacuum pump. In this way, multiple cold traps can be alternately operated.

[0032] In this embodiment, the water storage mechanism 5 includes a water reservoir, and a third valve 9 electrically connected to the control mechanism 1 is installed between the water inlet end of the water reservoir and the cold trap. A fourth valve 10 electrically connected to the control mechanism 1 is provided at the water outlet end of the water reservoir; and a liquid level detector is installed in the water reservoir, and the liquid level detector is electrically connected to the control mechanism. Therefore, when the water level in the water reservoir reaches the restricted area, the third valve is closed and the fourth valve is opened to realize the thawing process.

[0033] In this embodiment, the control mechanism includes a controller, and the controller includes Liona, YULIA, and Sagitta, so that the device can perform intelligent processing on the collected data and call appropriate control programs and process programs in the main database.

[0034] A multi-cold-trap freeze-drying method based on dynamic weighing, using the above-mentioned multi-cold-trap freeze-drying method, the method is as follows:

[0035] S1. Place the product to be dried into the freeze-drying chamber;

[0036] S2, start the first valve between the first cold trap and the vacuum pump and the second valve between the vacuum pump and the first cold trap, and after the first valve and the second valve have been running for a period of time, start the second cold trap and close the first valve and the second valve;

[0037] S3. When the first valve and the second valve are opened again, the second valve of the second cold trap will be closed for 3 seconds, and the first valve of the second cold trap will be closed for 3 seconds after the second valve of the second cold trap is closed.

[0038] In this embodiment, a thawing process is also included, which includes closing the first valve for 10 seconds, opening the third valve, returning the water in the cold trap to the water storage tank, and closing the fourth valve. When the water level reaches the restricted area, the third valve is closed and the fourth valve is opened.

[0039] Dynamic weighing is an important method proposed in this paper: a cylindrical reference is set at a fixed position in the drying chamber to compare the g' value when the actual product is weighed. The mass of the cylindrical reference (calibration parameter) is known to be m, and the calibration parameter is determined by the g value under standard atmospheric pressure. Assuming that the actual product mass under vacuum is m', mg is a constant Q, and the g' value can be obtained, then m'=Q / g'.

[0040] The following is a specific example, taking a double cold trap as an example to illustrate the operation mode of multiple cold traps alternating, as follows Figure 2 : Among them, 5 is a water storage tank, 3 is two cold traps, and 4 is a vacuum pump.

[0041] The drying process under vacuum conditions runs according to the following flow, with the functions of the various components explained (indicated by numbers):

[0042] 71 and 72 are the first valves 7 between the cold trap and the drying chamber, and the switching takes 6 seconds.

[0043] 81 and 82 are the second valves 8 between the vacuum pump and the system, and the switching takes 6 seconds.

[0044] 81 and 71 are turned on when they are first run. When 81 and 71 are turned on again, 82 will be turned off for 3 seconds, and 72 will be turned off for 3 seconds after 82 is turned off.

[0045] 72 and 82 will switch on automatically after 45 minutes or use the manual wake-up function, saying "Liona, switch trap" (valid in English: "Liona, switch trap"), the manual wake-up function will ask for confirmation. Attention!!! The manual switch must be made every 15 minutes after the last switch. When 82 and 72 are switched on, 81 will be switched off for 3 seconds, and 71 will be switched off for 3 seconds after 81 is switched off.

[0046] The above is a cycle.

[0047] The thawing process after the drying process is carried out according to the following process, and the functions of each component are explained (indicated by numbers):

[0048] There will be no defrost during the first run.

[0049] 10 is the valve between the system and the environment, which will be closed when the water flows back to the water reservoir.

[0050] When 71 is closed for 10 seconds, 91 starts to open, and when the water level reaches the limit area, 91 will close. When 10 is closed, 91 will open.

[0051] When 72 is closed for 10 seconds, 92 starts to open, and when the water level reaches the limit area, 92 will close. When 10 is closed, 92 will open.

[0052] The 91 or 92 will turn the warm water back on after it has been in the trap for 10 minutes and then the warm water returns to the reservoir. The operation of the 91 or 92 is identical.

[0053] Water Reservoir When the power is turned on, the water in the water reservoir will be automatically heated and the temperature will be maintained at 50°C. The water reservoir can be connected to the water pipe, and then it can automatically fill and drain water.

[0054] Under the premise that no conflict occurs, those skilled in the art may freely combine and superimpose the above-mentioned additional technical features.

[0055] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A multi-cold trap freeze-drying device based on dynamic weighing, characterized in that: The invention comprises a control mechanism and a drying body provided with a drying chamber, wherein the drying body is connected to a plurality of cold traps, wherein the plurality of cold traps are connected to a vacuum mechanism and a water storage mechanism, wherein the water storage mechanism is connected to a heating mechanism, and the control mechanism is electrically connected to the water storage mechanism, the heating mechanism and the vacuum mechanism, and is used for controlling the working states of the water storage mechanism, the heating mechanism and the vacuum mechanism.

2. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: A plurality of cold traps are connected to each other through tracks to form a ring structure.

3. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: A first valve electrically connected to the control mechanism is installed between the cold trap and the drying body.

4. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: The vacuum mechanism comprises a vacuum pump, and a second valve electrically connected to the control mechanism is installed at the output end of the vacuum pump.

5. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: The water storage mechanism comprises a water reservoir, and a third valve electrically connected to the control mechanism is installed between the water inlet end of the water reservoir and the cold trap.

6. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: The water outlet of the water reservoir is provided with a fourth valve electrically connected to the control mechanism.

7. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: A liquid level detector is installed in the water storage tank, and the liquid level detector is electrically connected to the control mechanism.

8. The multi-cold-trap freeze-drying device based on dynamic weighing according to claim 1, characterized in that: The control mechanism includes a controller, and the controller includes one or more of Liona, YULIA, and Sagitta.

9. A multi-cold trap freeze-drying method based on dynamic weighing, characterized in that: The freeze-drying method based on multiple cold traps according to any one of claims 1 to 8 is as follows: S1. Place the product to be dried into the freeze-drying chamber; S2, start the first valve between the first cold trap and the vacuum pump and the second valve between the vacuum pump and the first cold trap, and after the first valve and the second valve have been running for a period of time, start the second cold trap and close the first valve and the second valve; S3. When the first valve and the second valve are opened again, the second valve of the second cold trap will be closed for 3 seconds, and the first valve of the second cold trap will be closed for 3 seconds after the second valve of the second cold trap is closed.

10. The multi-cold-trap freeze-drying method based on dynamic weighing according to claim 9, characterized in that: It also includes a thawing process, which includes closing the first valve for 10 seconds, opening the third valve, returning the water in the cold trap to the water storage tank, and closing the fourth valve. When the water level reaches the restricted area, the third valve is closed and the fourth valve is opened.

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