JP6026231B2 - Energy-saving small-volume low-humidity work device - Google Patents

Description

  The present invention provides a low-humidity working space with a relatively small volume (less than 3 m 3) and low energy consumption with a dew point temperature of minus 10 degrees Celsius to minus 85 degrees Celsius (hereinafter, all temperatures are referred to as “Celsius”). It relates to a device to be realized.

  The low-humidity work space is necessary for the development and production of, for example, lithium ion batteries and lithium ion capacitors. Lithium reacts with nitrogen even at room temperature to produce lithium nitride (Li3N) when there is moisture. Lithium nitride reacts with water at room temperature and decomposes into lithium hydroxide (LiOH) and ammonia (NH3). It also reacts with carbon dioxide (CO2) and chemically changes to lithium carbonate (Li2CO3), and therefore the working space must be kept at a low humidity.

  In addition, organic EL elements used in organic EL display devices, which are expected as next-generation flat panel displays to replace liquid crystal display devices, are promising for use as solid light-emitting, inexpensive large-area full-color display elements and writing light source arrays. Active research and development is underway. However, organic substances such as organic light-emitting materials used in organic EL elements, electrodes, and the like are weak against moisture and performance and characteristics deteriorate rapidly.

  On the other hand, in recent years, development and improvement of lithium ion batteries, lithium ion capacitors, and organic EL have been intensified. In the experiments accompanying these developments, a small volume space with a very low dew point (for example, a space having a volume of 3 m 3 or less such as a glove box, a dry chamber, a work booth, etc.) is required.

  Further, when a dehumidifier using a dehumidification rotor using silica gel or zeolite as an adsorbent is employed, it is easy to lower the dew point of air in the working space to minus. However, the current ultra-low dew point dehumidifier using a two-stage or three-stage dehumidification rotor has a problem that the dehumidifier becomes larger and the initial cost becomes higher, and the running cost becomes higher. There was a disadvantage that it was not suitable for low-humidity spaces.

  As an improvement measure against the increase in energy consumption, outside air is supplied twice to the treatment area of the dehumidification rotor without providing a precooler or an intermediate cooler as in the technique disclosed in Patent Document 1 (predehumidification, main dehumidification) Through the invention, a device that saves energy and lowers the dew point of air was invented.

  Moreover, what was disclosed by patent document 2 implement | achieves the apparatus which returns a part of the air which passed the process area of the dehumidification rotor to the front | former stage of a process area with a circulation flow path, and supplies the air of low dew point temperature . (Fig. 3 etc.)

  Moreover, what was disclosed by patent document 3 is related with the humidity adjustment apparatus of the airtight chamber which adjusts the inside of airtight chambers, such as a glove box, to a predetermined humidity state, and adsorb | sucks the water | moisture content by an adsorbent by heating an adsorbent. Alternatively, the release can be controlled, and the humidity is adjusted by a line using an adsorbent from low humidity to high humidity.

JP 2002-052308 A JP 2010-075819 A Japanese Patent No. 4642440

  The one disclosed in Patent Document 1 can reduce the initial cost and running cost because a precooler and an intercooler are not provided. However, a low-humidity work space (3 m3 or less) having a relatively small capacity can be arbitrarily selected. A technique for accurately controlling the dew point is not disclosed.

  In addition, when the target dew point temperature is low, it is necessary to increase the amount of air flowing into the circulation channel, and it is necessary to change the flow rate of the circulation channel according to the target dew point temperature. As a result, there is no disclosure of a technique in which the amount of air supplied to the room changes and the dew point is controlled at a constant air volume.

  Further, in the case disclosed in Patent Document 3, when the inside of the sealed chamber is set to a low dew point, it takes time to reach a predetermined dew point temperature, and the fluctuation of the heater temperature for controlling the humidity increases, resulting in a short time. There is no disclosure of a technique for accurately controlling humidity with time. (FIG. 3 etc.) When the capacity of the glove box is further increased, the amount of the adsorbent increases, the container for containing the adsorbent also increases, and a technique for making the apparatus compact is not disclosed.

  The present invention has been made to solve the above problems, and provides a low-humidity working device having a small volume that can be accurately controlled with a constant air volume at an arbitrary constant dew point, and that can reduce energy consumption and reduce running costs. For the purpose.

  The most important feature of the present invention is that dew point control in a small-volume, low-humidity work chamber is combined with regeneration circulation and processing circulation so that a wide range of dew points can be set with high accuracy and energy saving effect is also achieved. And

  The small-volume low-humidity working device of the present invention is provided with a bypass path including a flow control device that joins a part of the low-humidity air that has passed through the adsorption zone of the dehumidifying rotor with the return air from the low-humidity working space, There is an advantage of controlling the dew point in the low-humidity working space. In other words, in a relatively small working space such as a glove box (generally less than 3m3), it is difficult to control the dew point with a small air volume, so the air volume is adjusted by the bypass path, and the air volume of the blower and the damper are adjusted. This makes it possible to achieve highly accurate dew point control with a constant small air volume.

  In addition, a part of the regenerated air is circulated to reduce the energy consumed for regeneration. Furthermore, by returning all the regeneration air to the processing side without exhausting, the regeneration exhaust duct becomes unnecessary, there is no indoor installation restriction, and the application range is wide.

FIG. 1 is a flow chart showing an embodiment of a small-volume low-humidity working apparatus according to the present invention.

  The dehumidification rotor is divided into an adsorption zone, a regeneration zone, and a purge zone with respect to the rotation direction, and the outside air and return air from the regeneration zone (hereinafter, air once passed through the flow path in the device is exhausted outside the device). The air that returns to the flow path again is called “return air”) and the air that mixes the return air from the low-humidity space and the part of the low-humidity treated air that has passed through the adsorption zone. By passing a bypass path provided with a flow control device that merges with the return air from the low humidity space, the dew point in the low humidity space is reduced by combining regeneration temperature proportional control and bypass flow control using the bypass path. The objective of providing a low-volume low-humidity work device that can control dew point with high accuracy by energy consumption was realized. In addition, since the volume required for dehumidification is small, the required amount of dehumidification is very small. By recirculating part of the regeneration air, it was possible to achieve dehumidification performance and energy saving at the same time.

  Hereinafter, it demonstrates along FIG. 1 which shows the Example of this invention. Reference numeral 1 denotes a dehumidifying rotor, which carries a moisture adsorbent such as silica gel or zeolite and has a honeycomb rotor shape. The dehumidifying rotor 1 is rotated by a motor (generally not shown), and is divided into zones as follows according to the rotation direction.

  That is, reference numeral 2 denotes an adsorption zone, where moisture in the air is adsorbed by the dehumidifying rotor 1. 3 is a purge zone, and 4 is a regeneration zone. The adsorbed moisture is desorbed from the dehumidifying rotor 1 by the high-temperature air passing through the regeneration zone 4.

  14 is a 2nd cooling coil, 15 is a 1st cooling coil, and a refrigerant | coolant is supplied from a refrigerator (not shown). An adsorption blower 18 sends the air cooled by the first cooling coil 15 and the air cooled by the second cooling coil 14 to the adsorption zone 2 and the purge zone 3.

  Reference numeral 16 denotes a regenerative heater that raises the air exiting the purge zone 3 to a reproducible temperature level. For example, an electric heater is used. A regeneration blower 17 sucks out air from the regeneration zone 4, and an outlet of the regeneration blower 17 is connected to the first cooling coil 15. That is, the air that enters the first cooling coil 15 is in a state where the outside air and the return air that has come out of the regeneration blower 17 are mixed. Reference numeral 5 denotes a small-volume low-humidity working space, to which air heated by the supply air heater 13 is supplied as necessary.

  The return air from the small volume low humidity work space 5 is cooled by the second cooling coil 14 through the small volume low humidity work space return air passage 6, condensed and dehumidified, and then exited from the first cooling coil 15. Mixed with dehumidified air. Further, a part of the low-humidity air that has passed through the adsorption zone of the dehumidifying rotor is transferred to the small-volume low-humidity working space return air path 6 by the processing air return air path 7 in the bypass path provided with the motor damper 10 as a flow control device. It passes before the second cooling coil 14.

  The small-volume low-humidity working apparatus of the present invention has the above-described configuration, and the operation thereof will be described below. First, the return air from the outside air and the regeneration blower is cooled by the first cooling coil 15 and condensed and dehumidified.

  The air that has been dehumidified due to condensation and dehumidification is sent to the adsorption zone 2 by the adsorption blower 18. It is adsorbed and dehumidified in the adsorption zone 2, heated by the supply air heater 13 as necessary, and sent to the small volume low humidity working space 5 to which the dry air is supplied. In addition, in order to make the air volume of the air supplied to the small volume low humidity working space 5 constant, a constant air volume control device CAV or the like may be used for the damper 11. A dew point detector 28 is provided in the small volume low humidity working space 5, and the dew point detector 28 communicates with the automatic control device 31. If the dew point in the small volume low humidity working space 5 is not the set dew point, the motor damper 10 and the processing blower inverter 29 control the flow rate of the air passing through the processing air return air passage 7 to be the set dew point. In the small-volume low-humidity working space 5, an experiment to be performed in an environment with a set dew point, such as a trial manufacture of a lithium battery, is performed.

  The air leaving the purge zone 3 is raised to a temperature level that can be regenerated by the regenerative heater 16 and sent to the regeneration zone 4. Part of the air leaving the regeneration zone 4 is branched and returned to the regeneration heater 16 through the regeneration circulation path 22. By performing this regeneration circulation, the humidity of the return air sent from the regeneration zone 4 to the first cooling coil 15 can be increased, and condensation dehumidification can be performed. The air volume passing through the regeneration circuit 22 is adjusted by the dampers 19 and 20 and the regeneration blower inverter 30. Further, the regeneration air is sent to the first cooling coil 15 as return air without being discharged out of the system, so that the regeneration exhaust duct becomes unnecessary. In this embodiment, the operation of the blower inverter, motor damper, and the like is performed using a plurality of automatic control devices. However, all or part of the operations may be performed manually.

  For example, a glove box having a volume of about 1 m3 (width 1600 mm, height 900 mm, depth 700 mm), in which the dry air outlet has a punching metal structure of 400 mm × 100 mm with an aperture ratio of 50% or an aperture ratio of 50%. In this case, the dry air supply amount SA to the glove box is practically about 100 m3 / h (the ventilation frequency is about 100 times / h, and the outlet wind speed is about 1.4 m / s). Even when the set value of the dew point temperature in the glove box is minus 65 degrees and the moisture load is only 0.4 g / h, the dew point temperature of the supplied dry air SA is set to minus 85 degrees or less in order to maintain the dew point temperature in the glove box. There is a need to. In order to achieve such ultra-low dew point dry air with a single-stage dehumidification rotor, 200 m 3 / h of the process outlet dry air, which is about twice the dry air supply amount SA, is passed through the process air return air passage 7. It is necessary to return to the processing inlet. Note that the regeneration heater capacity is required to be 1.18 KW under the operation conditions of the regeneration temperature of 220 ° C. and the dehumidifying air amount ratio (= purge: regeneration: treatment) = 1: 2: 18.

  In the same glove box as above, when the set value of the dew point temperature in the glove box is minus 45 degrees and the moisture load is 5.4 g / h, the dew point of the supplied dry air SA is maintained in order to maintain the dew point temperature in the glove box. In order to achieve this low dew point dry air, it is necessary to set the temperature to minus 75 ° C. or less. Of the processing outlet dry air, only about 50 m 3 / h of the dry air supply amount SA is 50 m 3 / h. This can be realized by returning to the processing inlet through the path 7. In the same manner as described above, the regeneration heater capacity is reduced to 0.62 KW even under the operation conditions of the regeneration temperature of 220 degrees and the dehumidification air amount ratio (= purge: regeneration: processing) = 1: 2: 18, and energy saving can be realized. .

  Furthermore, in the same glove box as above, when the set value of the dew point temperature in the glove box is minus 40 degrees and the moisture load is 9.5 g / h, the supplied dry air SA is maintained in order to maintain the dew point temperature in the glove box. The dew point temperature must be minus 70 degrees or less. In order to provide this low dew point dry air, it can be achieved even if the amount of air returned to the treatment inlet is zero among the treatment outlet dry air. In the same manner as described above, the regeneration heater capacity is reduced to 0.42 KW even when the regeneration temperature is 220 ° C. and the dehumidifying air flow ratio (= purge: regeneration: processing) = 1: 2: 18. realizable.

  As described above, by using the small-volume low-humidity working device of the present invention, the dew point of the small-volume low-humidity working space 5 can be accurately adjusted with a small amount of air by changing the amount of processing air passed through the processing air return air passage 7. The temperature can be controlled, and energy consumption can be reduced. As a result, it is not necessary to increase the air volume of the dry air supply amount SA even at a low dew point with a dew point temperature of minus 85 degrees C. Therefore, the dew point is not adversely affected by the rapid flow of air in the small volume low humidity working space. Can be tested. In addition, the above-described effect can be realized by a simple operation of controlling the blower inverter and damper.

  As described above, the present invention can provide a low-volume low-humidity working apparatus that can accurately control an arbitrary dew point temperature with a small amount of energy.

DESCRIPTION OF SYMBOLS 1 Dehumidification rotor 2 Adsorption zone 3 Purge zone 4 Regeneration zone 5 Small volume low humidity working space 6 Small volume low humidity working space return air path 7 Process air return air path 8, 11, 12, 19, 20, 21 Damper 9 Positive pressure Exhaust path 10 Motor damper 13 After heater 14 Second cooling coil 15 First cooling coil 16 Regenerative heater 17 Regenerative blower 18 Adsorption blower 22 Regenerative circuit 23, 24, 25 Temperature detector 26, 27 Flow rate detector 28 Dew point detector 29, 30 Inverter 31, 32, 33, 34, 35, 36 Automatic control equipment

Claims (4)

An air volume control device having a dehumidification rotor carrying a moisture adsorbent and dividing the dehumidification rotor into an adsorption zone, a regeneration zone, and a purge zone with respect to the rotation direction, and controlling the outside air from fully closed to open. The air is sucked in and mixed with the return air from the regeneration zone, passed through the first cooling coil, mixed with the return air from the second cooling coil, partially branched and passed through the adsorption zone, and the rest Pass through the purge zone, heat and flow to the regeneration zone, supply a part of the air that has passed through the adsorption zone to the small volume low-humidity working space of the supply destination, and the remaining part of the second cooling Passing through a bypass path having a flow rate control device communicating with the return air path from the small volume low humidity work space in front of the coil, the return air from the small volume low humidity work space is returned to the second cooling coil. The dew point detector provided in a small volume low-humidity working space, the dew-point detector small volume low humidity working apparatus characterized by controlling the flow rate of the bypass passage by the dew point of the. Said controlling the dew point of the small volume and low humidity working space by changing the regeneration temperature of the regeneration zone, small volume low humidity working apparatus of claim 1, wherein the proportional control the regeneration temperature. The tap a portion of the air through the regeneration zone, small volume low humidity working apparatus of claim 1, wherein the return to the said regeneration zone again mixed with air exiting the purge zone. The small-volume low-humidity working device according to claim 3 , wherein the exhaust portion of the air passing through the regeneration zone is returned to the first cooling coil and returned as a whole amount of air .

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