Gas variable-pressure drying device and method

Abstract

The invention discloses a gas variable-pressure drying device and method, the device comprises a drying chamber, a gas circulation unit and a pressure control unit, the drying chamber is provided with a drying cavity, and a gas inlet and a gas outlet which are communicated with the drying cavity; the gas circulation unit communicates with the drying cavity to drive air in the drying cavity to circularly flow; the pressure control unit communicates with the drying cavity to control the air pressure in the drying cavity. The method comprises the following steps that S1, materials are placed in the drying cavity, and the pressure control unit enables the air pressure in the drying cavity to rise to a preset high pressure value; and S2, the air circulation unit drives air in the drying cavity to flow circularly, and meanwhile, the pressure control unit enables the air pressure in the drying cavity to be reduced to a low pressure value. The air pressure in the drying cavity is changed through the pressure control unit, the air pressure is increased to the high pressure value firstly, most of water in the materials is rapidly extruded out, then the air pressure is reduced to the low pressure value, evaporation of residual water of the materials is promoted, energy consumption is remarkably reduced through the drying mode, and the drying device is suitable for heat-sensitive materials.

Description

Technical Field

[0001] The present invention relates to the field of drying technology, and in particular to a gas pressure-changing drying device and method. Background Art

[0002] In industrial production and daily life, the drying of materials is a crucial link, which is directly related to product quality, production efficiency and energy consumption. At present, the mainstream drying technology on the market mainly relies on low-temperature or normal-pressure gas, and achieves drying by heating the material to evaporate the water. The effect of saturated vapor pressure on water content is mainly reflected in the changes in pressure and temperature. At the same temperature, the saturated vapor pressure of water is basically fixed. When the total pressure increases, the original saturated water will condense with the increase of partial pressure, resulting in a decrease in the content of gaseous water. The higher the temperature, the more water vapor contained in the indoor air, and the lower the temperature, the less water vapor contained in the air, because the higher the temperature, the higher the saturated vapor pressure, and the higher the saturated moisture content per unit volume of air; the lower the temperature, the lower the saturated vapor pressure, and the lower the moisture content in the air.

[0003] Specifically, these traditional drying technologies usually use thermal energy as the driving force to achieve the purpose of drying by heating the surface of the material so that the moisture inside the material escapes in the form of steam. However, this method has several significant limitations. First, it usually consumes a lot of energy because a large amount of thermal energy is required to drive the evaporation of water. Secondly, for some heat-sensitive materials, such as certain foods, medicines and chemical raw materials, high temperature environments may cause their quality to deteriorate or even change their chemical or physical properties. Although these traditional drying technologies have achieved certain results in some aspects, their inherent high energy consumption and inadaptability to heat-sensitive materials are still problems that need to be solved. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies and propose a gas pressure swing drying device and method to solve the technical problems that the prior art uses heating to dry materials, which on the one hand consumes high energy and on the other hand is not suitable for heat-sensitive materials.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a gas pressure-variable drying device, comprising: a drying chamber having a drying chamber and an air inlet and an air outlet connected to the drying chamber; a gas circulation unit connected to the drying chamber to drive the air circulation flow in the drying chamber; and a pressure control unit connected to the drying chamber to control the air pressure in the drying chamber.

[0006] In some embodiments, the gas circulation unit includes a circulation pipe and a circulation fan. Both ends of the circulation pipe are connected to the drying chamber. The circulation fan is arranged on the circulation pipe to drive the air circulation flow.

[0007] In some embodiments, the gas circulation unit further includes a drying module, which is detachably disposed on the circulation pipe and is filled with a desiccant.

[0008] In some embodiments, the pressure control unit includes an air inlet valve, a pressure relief valve, an air intake pump and an air extraction pump. The air inlet valve is arranged at the air inlet, the pressure relief valve is arranged at the air outlet, the air intake pump is connected to the air inlet to pump air into the drying chamber, and the air extraction pump is connected to the air outlet to extract the air in the drying chamber.

[0009] In some embodiments, a control unit is also included, the control unit includes a controller, and the controller is respectively connected to the air intake valve, the pressure relief valve, the air intake pump, the air exhaust pump and the circulation fan signal control.

[0010] In some embodiments, the control unit further includes a pressure sensor, a temperature sensor and a humidity sensor disposed in the drying chamber, and the pressure sensor, the temperature sensor and the humidity sensor are respectively connected to the controller for signal transmission.

[0011] In the second aspect, the present invention also provides a gas pressure swing drying method, which is suitable for a gas pressure swing drying device, and includes the following steps: S1, placing the material in a drying chamber, and raising the air pressure in the drying chamber to a preset high pressure value through a pressure control unit; S2, driving the air circulation in the drying chamber through a gas circulation unit, and at the same time, reducing the air pressure in the drying chamber to a low pressure value at a preset rate through the pressure control unit.

[0012] In some embodiments, the high pressure value is 0.6 MPa to 1.0 MPa, and the low pressure value is 0.1 kPa to 0.3 kPa.

[0013] In some embodiments, the volume of the drying chamber is 0.5 m³ to 10 m³, and the flow rate of the air circulation driven by the gas circulation unit is 5 m³ / min to 10 m³ / min.

[0014] In some embodiments, the temperature of the drying chamber is 30°C to 80°C during the entire drying process.

[0015] Compared with the prior art, the gas pressure-variable drying device provided by the present invention changes the gas pressure in the drying chamber through a pressure control unit, first raising the gas pressure to a high pressure value to quickly squeeze out most of the moisture in the material, and then reducing the gas pressure to a low pressure value to promote the evaporation of residual moisture in the material and ensure the drying effect. This drying method significantly reduces energy consumption and is suitable for heat-sensitive materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of a gas pressure-changing drying device provided in an embodiment of the present invention; Figure 2 It is a flow chart of the gas pressure variable drying method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In order to solve the technical problems that the conventional technology uses heating to dry materials, which on the one hand has high energy consumption and on the other hand is not suitable for heat-sensitive materials, the present invention provides a gas pressure variable drying device and method, which can significantly reduce the energy consumption during drying and is suitable for heat-sensitive materials.

[0019] It should be noted that the gas pressure variable drying device described in the present invention is used for but not limited to drying batteries. For the convenience of explanation, in the present invention, only the gas pressure variable drying device drying batteries is used as an example for explanation. The principle of drying other heat-sensitive materials by the gas pressure variable drying device is substantially the same as the principle of drying batteries, which will not be described in detail here.

[0020] See also Figure 1 , Figure 1 Schematic diagram of the structure of a gas pressure-swing drying device in one embodiment of the present invention. The gas pressure-swing drying device includes a drying chamber 1, a gas circulation unit 2 and a pressure control unit 3.

[0021] The drying chamber 1 has a drying cavity and an air inlet 11 and an air outlet 12 connected to the drying cavity. It is easy to understand that the drying chamber 1 should also have a door for placing materials. After the materials to be dried (such as batteries) are placed in the drying cavity, the door is closed to start drying.

[0022] The gas circulation unit 2 is connected to the drying chamber to drive the air in the drying chamber to circulate.

[0023] The pressure control unit 3 is connected to the drying chamber to control the air pressure in the drying chamber. The pressure control unit 3 can both increase the air in the drying chamber to a predetermined value and decrease the air in the drying chamber to a predetermined value.

[0024] In some embodiments, the gas circulation unit 2 includes a circulation pipe 21 and a circulation fan 22. Both ends of the circulation pipe 21 are connected to the drying chamber. The circulation fan 22 is arranged on the circulation pipe 21 to drive the air circulation in the drying chamber.

[0025] In some embodiments, the gas circulation unit 2 further includes a drying module 23, which is detachably arranged on the circulation pipe 21, and is filled with a desiccant. The drying module 23 can further improve the drying capacity of the drying device, and the drying module 23 can adopt a porous box-shaped structure, and the circulation pipe 21 is correspondingly provided with a mounting groove or a mounting hole, and the drying module 23 can be correspondingly installed in the mounting groove or the mounting hole. It is also best to be sealed and connected with the circulation pipe 21, and the air tightness of the connection is improved by providing a sealing ring. The desiccant in the drying module 23 generally adopts a solid desiccant, such as quicklime, silica gel, etc.

[0026] In some embodiments, the pressure control unit 3 includes an air inlet valve 31, a pressure relief valve 32, an air inlet pump 33, and an air extraction pump 34. The air inlet valve 31 is disposed at the air inlet 11, and the pressure relief valve 32 is disposed at the air outlet 12, and is used to control the opening and closing of the air inlet 11 and the air outlet 12, respectively. The air inlet pump 33 is connected to the air inlet 11 to pump air into the drying chamber, thereby increasing the air pressure in the drying chamber. The air extraction pump 34 is connected to the air outlet 12 to extract the air in the drying chamber, thereby reducing the air pressure in the drying chamber to below one atmosphere.

[0027] In some embodiments, the gas pressure-variable drying device further includes a control unit 4, which includes a controller 41. The controller 41 is respectively connected to the air inlet valve 313, the pressure relief valve 2, the air inlet pump 33, the air exhaust pump 34 and the circulating fan 22 for signal control to control their working states so as to achieve the purpose of controlling the air pressure inside the drying chamber.

[0028] In some embodiments, the control unit 4 also includes a pressure sensor 42, a temperature sensor 43 and a humidity sensor 44 arranged in the drying chamber. The pressure sensor 42, the temperature sensor 43 and the humidity sensor 44 are respectively used to monitor the air pressure, temperature and humidity in the drying chamber, and are respectively connected to the controller 41 for signal transmission to provide data support for the controller 41 to control various components.

[0029] See also Figure 2 , Figure 2 The figure is a flow chart of a gas pressure swing drying method according to an embodiment of the present invention.

[0030] The gas pressure-swing drying method comprises the following steps: S1: placing the material into the drying chamber, and the pressure control unit 3 raises the air pressure in the drying chamber to a preset high pressure value to quickly squeeze out most of the water in the material.

[0031] The specific operation is that the controller 41 controls the air intake valve 31 to open, the pressure relief valve 32 to close, and the air intake pump 33 to start working to pump air into the drying chamber to increase the air pressure in the drying chamber until the pressure sensor 42 detects that the air pressure in the drying chamber reaches a preset high pressure value, and then controls the air intake valve 313 and the air intake pump 33 to close.

[0032] The S2 gas circulation unit 2 drives the air circulation in the drying chamber, and at the same time the pressure control unit 3 reduces the air pressure in the drying chamber to a low pressure value at a preset rate, thereby promoting the evaporation of residual moisture in the material and ensuring the drying effect.

[0033] The specific operation is that the controller 41 controls the circulation fan 22 to start working and drives the air to circulate at a certain rate. At the same time, the pressure relief valve 32 is controlled to open to a certain degree so that the air pressure in the drying chamber decreases at a preset rate. As the air pressure inside the drying chamber decreases, the exhaust rate of the air outlet 12 will also decrease. Therefore, the pressure relief valve 32 should increase its opening accordingly to compensate so that the rate of air pressure reduction remains within a preset range. When the air pressure in the drying chamber is close to one atmosphere, the pressure relief valve 32 is opened to the maximum and still cannot maintain the required pressure reduction rate. At this time, the controller 41 controls the vacuum pump 34 to start working, and the air in the drying chamber is extracted at a preset pressure reduction rate, so that the air pressure in the drying chamber is reduced to a low pressure value.

[0034] In some embodiments, the high pressure value is 0.6 MPa to 1.0 MPa, and the low pressure value is 0.1 kPa to 0.3 kPa.

[0035] In some embodiments, the volume of the drying chamber is 0.5m³ to 10m³, and the flow rate of the air circulation driven by the gas circulation unit is 5m³ / min to 10m³ / min. This is the size of the drying chamber adopted by the applicant when drying batteries, taking into account factors such as the equipment installation environment and the number of batteries to be dried. In other embodiments, those skilled in the art can increase or decrease the volume of the drying chamber according to actual production needs, and correspondingly adjust the flow rate of the air circulation.

[0036] In some embodiments, during the entire drying process, the temperature of the drying chamber is 30°C to 80°C to avoid degradation of the quality of heat-sensitive materials. In step S1, the air intake pump 33 pressurizes the drying chamber, which is accompanied by an increase in the temperature of the drying chamber. Therefore, it is necessary to control the pressurization rate to avoid the temperature in the drying chamber from exceeding the upper limit. The heat dissipation of the drying chamber 1 itself is used to maintain the temperature in the drying chamber stable. In step S2, the process of reducing the pressure in the drying chamber is also accompanied by a decrease in the temperature of the drying chamber. Similarly, the pressure reduction rate is controlled to avoid the temperature in the drying chamber from being too low.

[0037] In a specific embodiment, the volume of the drying chamber is customized to 5m³ according to the actual material batch to meet the specific production scale requirements. In the early stage of drying, the pressure in the drying chamber 1 is increased to 0.8MPa by the pressure control unit 3, which can quickly squeeze out most of the moisture in the material, laying a good foundation for the subsequent drying process.

[0038] Subsequently, in the later stage of drying, the gas pressure in the drying chamber is gradually reduced to 0.2 kPa. This fine pressure control strategy helps promote the evaporation of residual moisture in the material and ensure the thoroughness of the drying effect.

[0039] At the same time, the gas circulation unit 2 circulates the gas in the drying chamber at a rate of 8m³ / min and achieves a 92% gas recycling rate. This design significantly improves drying efficiency and reduces energy consumption. And during the entire drying process, the temperature of the drying chamber 1 is precisely controlled at around 50°C to ensure that the material will not be damaged due to excessive temperature during the drying process.

[0040] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A gas pressure-swing drying device, characterized in that: include: A drying chamber, comprising a drying chamber and an air inlet and an air outlet communicating with the drying chamber; A gas circulation unit connected to the drying chamber to drive the air in the drying chamber to circulate; as well as A pressure control unit is connected to the drying chamber to control the air pressure in the drying chamber.

2. The gas pressure-swing drying device according to claim 1, characterized in that: The gas circulation unit comprises a circulation pipeline and a circulation fan. Both ends of the circulation pipeline are connected to the drying chamber. The circulation fan is arranged on the circulation pipeline to drive the air to circulate.

3. The gas pressure-swing drying device according to claim 2, characterized in that: The gas circulation unit further comprises a drying module, which is detachably arranged on the circulation pipeline and is filled with a desiccant.

4. The gas pressure-swing drying device according to claim 2, characterized in that: The pressure control unit includes an air intake valve, a pressure relief valve, an air intake pump and an air extraction pump. The air intake valve is arranged at the air intake port, the pressure relief valve is arranged at the air outlet, the air intake pump is connected to the air intake port to pump air into the drying chamber, and the air extraction pump is connected to the air outlet to extract the air in the drying chamber.

5. The gas pressure-swing drying device according to claim 4, characterized in that: It also includes a control unit, which includes a controller, and the controller is respectively connected to the air intake valve, the pressure relief valve, the air intake pump, the air extraction pump and the circulation fan signal control.

6. The gas pressure-swing drying device according to claim 5, characterized in that: The control unit further comprises a pressure sensor, a temperature sensor and a humidity sensor which are arranged in the drying chamber. The pressure sensor, the temperature sensor and the humidity sensor are respectively connected to the controller for signal transmission.

7. A gas pressure-swing drying method, characterized in that: The gas pressure-swing drying device according to any one of claims 1 to 6 comprises the following steps: S1, placing the material into the drying chamber, and raising the air pressure in the drying chamber to a preset high pressure value through the pressure control unit; S2. The air circulation unit is used to drive the air in the drying chamber to circulate, and the pressure control unit is used to reduce the air pressure in the drying chamber to a low pressure value at a preset rate.

8. The gas pressure swing drying method according to claim 7, characterized in that: The high pressure value is 0.6 MPa to 1.0 MPa, and the low pressure value is 0.1 kPa to 0.3 kPa.

9. The gas pressure swing drying method according to claim 7, characterized in that: The volume of the drying chamber is 0.5m³ to 10m³, and the flow rate of the air circulation driven by the gas circulation unit is 5m³ / min to 10m³ / min.

10. The gas pressure swing drying method according to claim 7, characterized in that: During the whole drying process, the temperature of the drying chamber is 30°C to 80°C.

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