A cold trap for vacuum freeze drying

Abstract

A cold trap for vacuum freeze drying belongs to the technical field of cold traps for vacuum freeze drying. A left liquid inlet manifold is arranged in the left shell of the collector, connected to a left collecting pipe and then to a left return air manifold. The right side has the same symmetrical structure. A left vacuum partition is arranged in the left shell of the collector to form a left vacuum chamber. The left collecting pipe located on the left side passes through the left vacuum partition and extends into the left vacuum chamber. The left vacuum chamber corresponds to the left vacuum port. A left vacuum partition opening is arranged at the lower edge of the left vacuum partition. The closer the multiple left vacuum partition openings are to the left vacuum port, the larger the spacing is, and the farther they are from the left vacuum port, the smaller the spacing is. The left liquid inlet manifold has an extension section to the upper left side. The right side has the same symmetrical structure. On the one hand, the present invention can maintain the vacuum degree in the drying chamber. On the other hand, a large amount of water vapor is adsorbed on the low-temperature collecting pipe of the cold trap and frozen into ice, so that the vacuum freeze drying equipment can realize its working process with the highest efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of cold traps for vacuum freeze drying, and in particular relates to a cold trap for vacuum freeze drying. Background Art

[0002] The cold trap is a critical component of vacuum freeze-drying equipment. During drying, the material to be dried is fed into the drying chamber, which is then evacuated to a set vacuum level. The heating plate temperature automatically adjusts according to a pre-set temperature curve to provide the heat required for ice in the material to sublime. During this process, a large amount of moisture in the material sublimates into water vapor. The vacuum pump's capacity is insufficient to remove this water vapor within a specified timeframe, and removing large amounts of water vapor significantly reduces the pump's performance and impairs its proper operation.

[0003] The vacuum port of the original cold trap is on one side of the cold trap, which will cause uneven ice formation on the surface of the collection tube, and the closer to the vacuum port, the thicker the ice layer.

[0004] The present invention solves this problem by using a cold trap with a temperature range of -20°C to -60°C as a "cryopump." On the one hand, it maintains the vacuum level in the drying chamber. On the other hand, a large amount of water vapor is adsorbed on the cold trap's low-temperature collection tube and frozen into ice, enabling the vacuum freeze-drying equipment to operate at the highest efficiency. Summary of the Invention

[0005] The purpose of the present invention is to provide a cold trap for vacuum freeze drying, which improves the ability to capture water vapor, increases the utilization rate of the capture tube, and minimizes the dependence on the vacuum pump to extract water vapor.

[0006] The technical solution adopted is:

[0007] A cold trap for vacuum freeze drying comprises a left trap part and a right trap part.

[0008] The left part of the trap includes a left trap shell and a plurality of left trap tubes.

[0009] The right part of the trap includes a right trap shell and a plurality of right trapping pipes.

[0010] The left shell of the collector and the right shell of the collector are connected through a middle partition.

[0011] A transversely arranged left liquid inlet manifold is provided in the left shell of the collector. The left liquid inlet manifold is connected to a plurality of left collecting pipes, and the plurality of left collecting pipes are connected to a transversely arranged left air return manifold.

[0012] The left return air manifold is located above the left liquid inlet manifold.

[0013] The left liquid inlet manifold and the left air return manifold are arranged on the rear side of the left shell 1 of the collector.

[0014] A right liquid inlet manifold is arranged transversely in the right shell of the collector. The right liquid inlet manifold is connected to a plurality of right collecting pipes, and the plurality of right collecting pipes are connected to a right air return manifold arranged transversely.

[0015] The right side return air manifold is located above the right side liquid inlet manifold.

[0016] The right liquid inlet manifold and the right air return manifold are arranged on the rear side of the right shell of the collector.

[0017] Its characteristics are:

[0018] A vertically arranged left vacuum diaphragm is fixed on the left side of the left shell of the collector, forming a left vacuum cavity at the left tip, and multiple left collecting pipes on the left side pass through the left vacuum diaphragm and extend into the left vacuum cavity.

[0019] The left vacuum chamber corresponds to the left vacuum port opened on the left shell of the collector.

[0020] The left vacuum partition is provided with a plurality of left vacuum partition openings.

[0021] A vertically arranged right vacuum partition is fixed on the right side of the right shell of the collector, forming a right vacuum cavity at the right tip, and multiple right collecting pipes on the right side pass through the right vacuum partition and extend into the right vacuum cavity.

[0022] The right vacuum chamber corresponds to the right vacuum port opened on the right shell of the collector.

[0023] The right vacuum diaphragm has a plurality of right vacuum diaphragm openings.

[0024] A plurality of left vacuum diaphragm openings are located at a lower edge of the left vacuum diaphragm.

[0025] A plurality of right vacuum diaphragm openings are located at a lower edge of the right vacuum diaphragm.

[0026] The closer the multiple left vacuum partition openings are to the left vacuum port, the larger the spacing is, and the farther away from the left vacuum port, the smaller the spacing is.

[0027] The closer the multiple right vacuum partition openings are to the right vacuum port, the larger the spacing is, and the farther away from the right vacuum port, the smaller the spacing is.

[0028] A portion of the left liquid inlet manifold is a transversely arranged straight pipe, and also has an extension section upward to the left, which is in a shape bent upward to the left along the shape of the left shell of the collector.

[0029] A portion of the right liquid inlet manifold is a transversely arranged straight pipe, and also has an extension section upward to the right, which is in a shape bent upward to the right along the shape of the right shell of the collector.

[0030] Its advantages are:

[0031] The present invention solves the aforementioned problems by using a cold trap with a temperature range of -20°C to -60°C as a "cryopump." On the one hand, it maintains the vacuum level within the drying chamber. On the other hand, a large amount of water vapor is adsorbed on the cold trap's cryogenic collection tube and frozen into ice, enabling the vacuum freeze-drying equipment to operate at maximum efficiency. This makes it a highly efficient cold trap for vacuum freeze-drying. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a rear view of the present invention.

[0033] Figure 2 This is the rear view of the original cold trap.

[0034] Figure 3 It is a rear half-section view of the invention.

[0035] Figure 4 This is the rear half-section of the original cold trap.

[0036] Figure 5 It is a structural schematic diagram of the collector of the present invention (the left shell part of the collector).

[0037] Figure 6 A side view of the left vacuum partition.

[0038] Figure 7 This is the front view of the left vacuum partition.

[0039] Collector left shell 1, left liquid inlet manifold 2, left vacuum partition opening 3, left collecting pipe 4, left vacuum chamber 5, left vacuum partition 6, left return air manifold 7, left return air pipe 8, middle partition 9, right vacuum partition 10, right vacuum port 11, right vacuum chamber 12, collector right shell 13, left liquid inlet pipe 14, left collecting pipe support plate through hole 15, left collecting pipe support plate 16.

[0040] The original liquid inlet manifold 17, the original vacuum port 18, the original gas return manifold 19, the original collecting pipe 20, the original collecting pipe support plate 21, and the original middle partition plate 22. DETAILED DESCRIPTION

[0041] A cold trap for vacuum freeze drying comprises a left trap part and a right trap part.

[0042] The left part of the trap includes a left trap housing 1 and a plurality of left trap pipes 4 .

[0043] The right part of the trap includes a right trap housing 13 and a plurality of right trap pipes.

[0044] The left collector shell 1 and the right collector shell 13 are connected via a middle partition 9 .

[0045] A transversely arranged left liquid inlet manifold 2 is provided in the left shell 1 of the collector. The left liquid inlet manifold 2 is connected to a plurality of left collecting pipes 4 , and the plurality of left collecting pipes 4 are connected to a transversely arranged left air return manifold 7 .

[0046] The left side return air manifold 7 is located above the left side liquid inlet manifold 2 .

[0047] The left liquid inlet manifold 2 is connected to the left liquid inlet pipe 14 outside the left shell 1 of the collector.

[0048] The left side return air manifold 7 is connected to the left side return air pipe 8 outside the left shell 1 of the collector.

[0049] A vertically arranged left vacuum diaphragm 6 is fixed on the left side of the left shell 1 of the collector, forming a left vacuum cavity 5 at the left tip. Multiple left collecting pipes 4 on the left side pass through the left vacuum diaphragm 6 and extend into the left vacuum cavity 5.

[0050] The left vacuum chamber 5 corresponds to the left vacuum port opened on the rear side of the left shell 1 of the collector.

[0051] The left liquid inlet manifold 2 and the left air return manifold 7 are arranged on the rear side of the left shell 1 of the collector.

[0052] There are multiple left vacuum diaphragm openings 3 on the lower edge of the left vacuum diaphragm 6. The closer to the rear side of the left shell 1 of the collector (the left vacuum port), the larger the spacing between the left vacuum diaphragm openings 3 is, and the farther away from the rear side of the left shell 1 of the collector, the smaller the spacing between the left vacuum diaphragm openings 3 is. Figure 6 As shown, the spacing between the horizontally flat rectangular left vacuum partition openings 3 on the right side (the rear side of the left collector shell 1) is 350 mm, and the spacing becomes smaller towards the left.

[0053] The left vacuum port is on the rear side of the left vacuum partition 6. The pumping speed on the rear side is relatively large. This arrangement of the left vacuum partition opening 3 will make the pumping speed of the left vacuum chamber 5 basically consistent, and the ice on the left collection tube 4 will be very uniform, thereby improving the utilization rate of the left collection tube 4.

[0054] A portion of the left liquid inlet manifold 2 is a transversely arranged straight pipe (for connecting to the left liquid inlet pipe 14 ), and also has an extension section upward to the left, which is bent upward to the left along the shape of the left shell 1 of the collector.

[0055] A plurality of left collecting tube support plates 16 are arranged vertically in parallel in the left shell 1 of the collector. A plurality of left collecting tubes 4 pass through the left collecting tube support plates 16 and are supported by the left collecting tube support plates 16. A plurality of left collecting tube support plate through holes 15 are opened on the left collecting tube support plates 16.

[0056] A right liquid inlet manifold is disposed transversely in the right shell 13 of the collector. The right liquid inlet manifold is connected to a plurality of right collecting pipes, and the plurality of right collecting pipes are connected to a right air return manifold disposed transversely.

[0057] The right side return air manifold is located above the right side liquid inlet manifold.

[0058] The right liquid inlet manifold is connected to the right liquid inlet pipe outside the right shell 13 of the collector.

[0059] The right side return air collection pipe is connected to the right side return air pipe outside the right shell 13 of the collector.

[0060] A vertically arranged right vacuum diaphragm 10 is fixed on the right side of the right shell 13 of the collector, forming a right vacuum cavity 12 at the right tip. Multiple right collecting pipes located on the right side pass through the right vacuum diaphragm 10 and extend into the right vacuum cavity 12.

[0061] The right vacuum chamber 12 corresponds to the right vacuum port 11 opened on the rear side of the right shell 13 of the collector.

[0062] The right liquid inlet manifold and the right air return manifold are arranged on the rear side of the right shell 13 of the collector.

[0063] There are multiple right vacuum partition openings on the lower edge of the right vacuum partition 10. The closer to the rear side of the right shell 13 of the collector (the right vacuum port 11), the larger the spacing between the right vacuum partition openings, and the farther away from the rear side of the right shell of the collector, the smaller the spacing between the right vacuum partition openings.

[0064] The right vacuum port 11 is on the rear side of the right vacuum partition 10. The pumping speed on the rear side is relatively high. This arrangement of the right vacuum partition opening will make the pumping speed at various locations in the right vacuum chamber 12 basically consistent, and the ice on the right collection tube will be very uniform, thereby improving the utilization rate of the right collection tube.

[0065] A portion of the right liquid inlet manifold is a transversely arranged straight pipe (for connecting the right liquid inlet pipe), and also has an extension section upward to the right, which is bent upward to the right along the shape of the right shell 13 of the collector.

[0066] A plurality of right collecting tube support plates are arranged vertically in parallel in the right shell 13 of the collector. A plurality of right collecting tubes pass through the right collecting tube support plates and are supported by the right collecting tube support plates. A plurality of right collecting tube support plate through holes are provided on the right collecting tube support plates.

[0067] The left and right capture parts are arranged symmetrically.

[0068] like Figure 2 and 4As shown in the figure, the vacuum port of the original cold trap is on one side of the cold trap, which causes uneven ice formation on the surface of the capture tube, with the ice layer thicker the closer to the vacuum port. To ensure uniform ice formation on the capture tube, vacuum chambers are set up on the side of the cold trap. The capture tube area and the vacuum chamber are separated by vacuum baffles. Vacuum baffles are opened at the bottom of the vacuum baffles. When the captured gas reaches the vacuum chamber, the vacuum chamber also acts as a pressure equalizing chamber, maintaining consistent pressure at the front and back of the cold trap. This ensures uniform ice formation on the capture tube and improves capture efficiency.

[0069] The capture capacity of the cold trap is closely related to the unit capture area. The larger the unit capture area, the greater the capture capacity. The cold trap consists of a trap shell and a capture tube inside the shell. While the outer dimensions of the capture shell remain unchanged, the internal structure is optimized. In this embodiment, due to the change in structure, the original 60 capture tubes on a single side can be increased to 72 on a single side (see Figure 3 and Figure 4 ), the length of a single piece remains unchanged, and the capture area increases by 20%.

[0070] When the trap is operating, refrigerant enters the liquid inlet manifold from the two liquid inlet pipes, is distributed to the various trap pipes, and then is collected in the return gas manifold, from which it returns to the refrigeration system. Water vapor flows into the cold trap through the respective openings on the two trap shells (openings on the left trap shell and openings on the right trap shell). Most of the water vapor is captured by the trap pipes, while the uncaptured part enters the vacuum chamber through the openings in the vacuum diaphragm and is then extracted by the vacuum pump through the vacuum port.

[0071] like Figure 1 As shown in the figure, the liquid inlet manifold is made into an angled structure (the utilization of the space on the slope) breaks through the original refrigeration industry's inherent idea that the liquid inlet manifold can only be straight. Figure 2 ), the collection tube arrangement area is increased, while the tube spacing remains unchanged, the thickness of the water vapor captured on the collection tube surface and turned into ice remains unchanged, the number of tubes increases, and the single-side collection capacity also increases.

[0072] In order to improve the capture efficiency of the cold trap, a capture tube is set in the vacuum chamber. This will allow some of the uncaptured water vapor to be captured again in the vacuum chamber. At the same time, the capture tube in the vacuum chamber acts as another level of "cryogenic pump", thereby increasing the vacuum pumping speed.

[0073] By adopting these measures, the water vapor capture rate was increased from 99% to 99.5% without changing the refrigeration equipment. This reduced the load on the vacuum pump, allowing for a smaller vacuum pump to be used, resulting in energy savings and reduced vacuum pump purchase costs. The reduced amount of water vapor that needs to be extracted by the vacuum pump reduces damage to the pump, reducing operating and maintenance costs.

[0074] There are respective pipes below the left shell 1 and the right shell 13 of the trap corresponding to the water inlet of the ice melting tank.

Claims

1. A cold trap for vacuum freeze drying, comprising a left trap part and a right trap part; The left part of the collector comprises a left collector shell (1) and a plurality of left collector pipes (4); The right part of the collector includes a right shell (13) of the collector and a plurality of right collecting pipes; The left collector shell (1) and the right collector shell (13) are connected via a middle partition (9); A left liquid inlet header (2) is disposed in a transverse manner in the left shell (1) of the collector. The left liquid inlet header (2) is connected to a plurality of left collecting pipes (4). The plurality of left collecting pipes (4) are connected to a left air return header (7) disposed in a transverse manner. The left air return manifold (7) is located above the left liquid inlet manifold (2); The left liquid inlet manifold (2) and the left air return manifold (7) are arranged on the rear side of the left shell 1 of the collector; A right liquid inlet header is disposed in the right shell (13) of the collector, the right liquid inlet header is connected to a plurality of right collecting pipes, and the plurality of right collecting pipes are connected to a right air return header disposed in a horizontal manner; The right air return header is located above the right liquid inlet header; The right liquid inlet manifold and the right air return manifold are arranged on the rear side of the right shell (13) of the collector; Features: A left vacuum baffle (6) arranged vertically is fixed on the left side of the left shell (1) of the collector, forming a left vacuum chamber (5) at the left tip, and a plurality of left collecting pipes (4) located on the left side pass through the left vacuum baffle (6) and extend into the left vacuum chamber (5); The left vacuum chamber (5) is provided with a left vacuum port corresponding to the left shell (1) of the collector; The left vacuum baffle (6) is provided with a plurality of left vacuum baffle openings (3); A right vacuum diaphragm (10) arranged vertically is fixed on the right side of the right shell (13) of the collector, forming a right vacuum chamber (12) at the right tip, and a plurality of right collecting pipes located on the right side pass through the right vacuum diaphragm (10) and extend into the right vacuum chamber (12); The right vacuum chamber (12) is provided with a right vacuum port (11) corresponding to the right shell (13) of the collector; The right vacuum partition (10) has a plurality of right vacuum partition openings; A plurality of left vacuum baffle openings (3) are located at the lower edge of the left vacuum baffle (6); A plurality of right vacuum diaphragm openings are located at the lower edge of the right vacuum diaphragm (10); A portion of the left liquid inlet manifold (2) is a straight pipe arranged transversely, and also has an extension section extending upward to the left, which is in a shape that bends upward to the left along the shape of the left shell (1) of the collector; A portion of the right liquid inlet manifold is a horizontally arranged straight pipe, and also has an extension section extending upward to the right side, which is in a shape that bends upward to the right side along the shape of the right shell (13) of the collector; The left vacuum port is located at the rear side of the left vacuum partition (6), and the right vacuum port (11) is located at the rear side of the right vacuum partition (10).

2. A cold trap for vacuum freeze drying according to claim 1, characterized in that: The closer the multiple left vacuum baffle openings (3) are to the left vacuum port, the larger the spacing is, and the farther they are from the left vacuum port, the smaller the spacing is; The closer the openings of the plurality of right vacuum partitions are to the right vacuum port (11), the larger the spacing is, and the farther away from the right vacuum port (11), the smaller the spacing is.

3. A cold trap for vacuum freeze drying according to claim 2, characterized in that: The left vacuum partition opening (3) and the right vacuum partition opening are both flat rectangular.

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