JP2012011343A - Apparatus for generating low dew point air - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for generating low dew point air which enables the energy consumption thereof for generating the low dew point air to be considerably reduced than before and which supplies the desired low dew point air in a short period of time after the apparatus is operated.SOLUTION: The apparatus 10 for generating low dew point air includes a moisture condensation unit 12, a temperature swing adsorption unit 14 and a low dew point air supply unit 16. The moisture condensation unit 12 includes a moisture condensation/removal mechanism and is used for dehumidifying the treated air. The temperature swing adsorption unit 14 has two series of adsorbent parts 18a, 18b and is used for adsorbing the moisture in the dehumidified treated air to produce the low dew point air. The low dew point air supply unit 16 includes a temperature adjustment mechanism and is used for adjusting the temperature of the air subjected to the temperature swing adsorption and supplying the temperature-adjusted low dew point air to supply destinations. The apparatus for generating low dew point air further includes first and second automatic four-port selector valves 22a, 22b each of which is used for selecting a flow passage of the air circulating between the connected units.

Description

  The present invention relates to a low dew point air generator.

  Low dew point air of about −30 to −80 ° C. and ultra low dew point air of about −80 to −120 ° C. are used for lithium ion battery manufacturing, organic EL display, liquid crystal display and organic thin film solar cell manufacturing, and VLSI. Used in manufacturing.

  As a low dew point air production apparatus / supply system, a cryogenic separation / mixing system, a PSA (pressure swing adsorption) apparatus, and an adsorption rotor type apparatus are known. On the other hand, as a manufacturing apparatus for ultra-low dew point air, an adsorption rotor type apparatus is preferably used from the viewpoint of manufacturing cost among these apparatuses.

The cryogenic separation / mixing method is, for example, removing dust from the atmosphere, then compressing to 3.5 to 5.1 MPa, and deeply cooling to -191 ° C by adiabatic expansion operation to obtain liquid air, which is fractionally distilled After liquid nitrogen and liquid oxygen are vaporized, they are mixed in a volume ratio of nitrogen gas to oxygen gas of about 4 to 1 and recompressed to 15.2 MPa (G). In this method, a high pressure vessel is filled to obtain clean pseudo air with an ultra-low dew point.
However, the cryogenic separation / mixing method requires expensive high-pressure gas production equipment and requires a large amount of energy for the compression work twice. For this reason, the cryogenic separation / mixing method requires only a small amount of air consumption, for example, less than about 5 L / min. For example, in the semiconductor field, in a very limited place such as a mask manufacturing process or an exposure process manufacturing apparatus. used.

A PSA device is a device that obtains low dew point air by pressure swing adsorption by alternately performing a treatment step of passing treatment air through an adsorption vessel containing an adsorbent and a regeneration step of passing regeneration air. In this case, the processing air is actually allowed to flow into the PSA apparatus after performing compression dehumidification and cooling dehumidification as pretreatment.
However, since the PSA device is a facility that requires pressure resistance performance, the installation location of the device having a large amount of processing air is restricted by legal regulations as well as a large amount of capital investment. Moreover, since the air under atmospheric pressure is compressed, energy consumption is enormous. Moreover, since the dehumidified air produced by the PSA apparatus operated at a critical pressure of 3.5 MPa or less does not pass through the state of liquefied air, it is assumed that more moisture remains than that through liquefied air, The air does not have a very low dew point. For this reason, the PSA apparatus is used in a very limited place where the consumption of air is small as in the case of the cryogenic separation / mixing method.

By the way, when the supply destination of the low dew point to the ultra low dew point air is a work space in a manufacturing apparatus such as a dry room, a drive source, a dry clean room, a dry clean booth, a dry clean mini-environment, and a lithium ion battery, 1 to 100 m. Air of about ³ / min is required. At this scale, the cryogenic separation / mixing system using a compressor and the PSA apparatus are clearly not practical. In the case of a clean room with a low dew point, the dew point temperature of air is normally maintained at −10 ° C. or lower, and the moisture in the air is only a few ppm or lower.

On the other hand, the adsorption rotor type device is a practical device capable of generating air having a low dew point or an ultra-low dew point. Since the adsorption rotor type device processes air under normal pressure, a large amount of air can be obtained and the energy consumption is relatively small compared to the cryogenic separation / mixing method and PSA (pressure swing adsorption) device. The equipment cost is also low.
The adsorption rotor type device is a device for dehumidifying the processing air by passing the processing air through a rotatable rotor. As the rotor, an adsorbent formed in a honeycomb shape is used.

  For example, a dehumidifying device is disclosed in which three stages of rotors are provided so that continuously dehumidified air can be produced (see Patent Document 1).

  In this dehumidifying device, each stage rotor is divided into a dehumidifying zone, a regeneration zone, and a purge zone, and each zone is provided with a dehumidifying air passage, a regenerating air passage and Connected to purge vent. A cooler is disposed in the upstream dehumidifying air passage of each stage rotor, and a cooler is also disposed in the purge air passage as necessary. A heater is disposed in the regeneration air passage. A total of six blowers (fans) are installed before and after each stage rotor in the dehumidification vent and the regeneration vent.

  The distribution of air to each of the dehumidifying air passage, the regeneration air passage, and the purge air passage is adjusted by the opening degree of a large number of damper type automatic valves installed in each air passage. The flow direction of the dehumidifying air and the flow direction of the regeneration air and the purge air are countercurrent. Therefore, the air passing through each of the dehumidifying zone, the regeneration zone, and the purge zone is structurally avoided from being mixed from other zones due to a pressure difference or a flow rate difference at the connection point between the end faces of the rotor and the end face chambers. Absent. Therefore, not only the pressure adjustment and flow rate adjustment of the rotor end face and both end face chambers are precisely performed by the damper type automatic valve, but also the branch point of the dehumidification air passage and the purge air passage, the purge air passage and the regeneration air passage. It is necessary to provide the junction of the road at many places.

In addition, a large amount of energy loss occurs in order to stably generate the desired low dew point air at a predetermined flow rate.
First, when the pressure and / or flow rate of the air sent to each ventilation path is adjusted by the damper type automatic valve, a pressure loss is inevitably generated, and an energy loss corresponding to the pressure loss cannot be avoided.
In addition, the dehumidification vent, regeneration vent, and purge vent connected to the chambers at both ends of the stage rotors having different cross-sectional shapes and cross-sectional shapes from the dehumidifying zone, the regeneration zone, and the purge zone are enlarged in cross-sectional area. Since there is a cross-sectional area reduction, energy loss commensurate with the generated pressure loss is unavoidable.
The flow rate of air vented to each air passage and each area is not only different, but generally increases in the order of dehumidification area <regeneration area <purge area, and conversely, the area of the area Is reduced in the order of dehumidification zone> regeneration zone> purge zone, so the loss of each vent of each zone, each stage rotor, and the chambers at both ends thereof is reduced in the order of dehumidification zone <regeneration zone <purge zone. Will increase. That is, a large pressure loss occurs in the regeneration zone and the purge zone as compared to the dehumidifying zone.

When analyzing the contents of paragraph numbers [0033] to [0037] in the detailed explanation column of the invention of Patent Document 1, a large pressure loss with fluctuation occurs in the regeneration air passage and the purge air passage of the second stage rotor. However, as shown in Patent Document 1 and FIG. 1, it is inevitable to install a processing fan and a regeneration fan. Further, pressure loss occurs in the regeneration air passage and purge air passage of the third stage rotor. In other words, the development of a system or device that achieves energy saving with reduced energy loss due to pressure loss occurring at these locations of the rotor type dehumidifier is the first issue.
Furthermore, when the reason why the above-described pressure loss occurs was examined, it was found that this problem cannot be avoided as long as the adsorption rotor type dehumidifier is employed. Each stage rotor is rotating at 0.5 to 15 rph. Of the ratio (area ratio) of the air passing area on the rotor end face side, the dehumidifying area is the moisture adsorption time on the adsorbent, and the regeneration area is from the adsorbent. The heat desorption time of water and the purge zone represent the cooling time of the adsorbent. For example, as described in Paragraph No. [0034] of Patent Document 1, the ratio of each area of the second stage rotor end face is represented by a central angle, the dehumidification area is 270 degrees, the regeneration area is 60 degrees, Since the purge zone is 30 degrees, when the second stage rotor rotates at 2 rph, the adsorption time is 22.5 minutes, the heat desorption time is 5 minutes, and the cooling time is 2.5 minutes.

  In other words, the processing air temperature is adjusted to 5 ° C. for 22.5 minutes to flow into the adsorbent rotor to adsorb a predetermined amount of water, and the adsorbent is heated to a regeneration temperature of 120 ° C. for 5 minutes and then further adsorbed. The amount of heat required for desorption from the material, that is, desorption regeneration is applied, and the adsorbent heated for heating desorption is cooled to a processing temperature of 5 ° C. for 2.5 minutes. Is set.

  However, in the system configuration shown in FIG. 1 of Patent Document 1, if the moisture adsorbed in 22.5 minutes is heated and desorbed in 5 minutes, heated air having a flow rate higher than the air flow rate passed through the dehumidified area in the regeneration area. Requires flow. According to the contents of the description [0033] to [0035], the rotors in the first, second, and third stages use 1.4 times the flow rate passed through the dehumidification area in the regeneration area. . In order to send this increased and heated air flow to the regenerative air passage having a smaller cross-sectional area than the dehumidifying air passage, the suction rotor type dehumidifying device inevitably has a dehumidifying air passage. Produces a greater pressure loss.

  On the other hand, the purge air passage uses the same amount as that passed through the dehumidification zone in the purge zone of the second and third stage rotors from the contents described in the documents [0034] and [0035]. . However, since this purge air is sent to the purge air passage having a passage cross-sectional area smaller than the passage cross-sectional area of the dehumidifying air passage, the suction rotor type dehumidifier is inevitably more than the dehumidifying air passage. This is a problem including a regenerative air passage in which a large pressure loss must be generated.

  Moreover, although the temperature is adjusted to a predetermined value in any of the techniques of Patent Document 1 and Non-Patent Document 1 described later, an attempt is made to adjust the amount of water in the processing air flowing into the first stage rotor to a predetermined absolute humidity. However, since the pressure loss of each air passage fluctuates, the processing air flow rate and the circulating air amount cannot be adjusted to a predetermined constant flow rate. Therefore, the specific enthalpy of the mixed air composed of the processing air and the circulating air flowing into the first stage rotor cannot be set to a predetermined value for obtaining a predetermined low dew point stably and reliably. That is, there is a problem that the rotor type dehumidifying device is not suitable as a device that stably and reliably manufactures low dew point air at a predetermined flow rate.

Furthermore, the adsorption rotor type device has to adjust a number of operating variables. For this reason, it takes a long time to reach a steady state.
That is, for example, in the case of a three-stage adsorption rotor type dehumidifier, when starting up to obtain air with a desired ultra-low dew point, the rotor of each stage is divided into three areas. It is necessary to adjust at least 20 operating variables consisting of pressure, temperature, moisture and rotor speed. For this reason, it is assumed that the required rise time required to reach the steady condition from the condition immediately after the start-up and to stably obtain air having a desired ultra-low dew point takes a long time.
There is also a report that it takes about 300 hours as the required rise time (see Non-Patent Document 1). In this case, it is necessary to start the three-stage dehumidifier about 300 hours before the time required by the supply destination. In addition, since the air generated during about 300 hours is air that does not reach the desired dew point, it is discharged without being used.
This wastes a large amount of energy during device startup. Further, since it takes a long time for the apparatus to become stable in this way, it becomes difficult to correct the supply condition of the low dew point air in response to the request of the supply destination during operation of the apparatus.

JP-A-11-188224

Chemical Engineering Vol. 26, No. 3, 332, 2000

  The problems to be solved are the above-mentioned points, and in particular, the conventional low dew point air generator has a large energy consumption when generating the low dew point air. It takes a long time to become possible.

A low dew point air generator according to the present invention includes a moisture condensing unit that condenses and removes moisture in the processing air, a temperature swing adsorption unit that adsorbs the moisture that has been condensed and removed by temperature swing, and air after temperature swing adsorption. It has a low dew point air supply unit that adjusts the temperature and supplies it to the supply destination.
The temperature swing adsorption unit has two series of adsorbent parts for the moisture adsorption process and the moisture desorption process provided so that the inflow flow path of the processing air can be switched, and flows out from the adsorbent part used for the moisture adsorption process. A regenerative air supply unit is provided for supplying a part of the air after the temperature swing adsorption to the adsorbent unit used for the moisture desorption process.

  The low dew point air generator according to the present invention is preferably configured to switch a flow path between the moisture condensation unit, the two series of adsorbent parts, the regeneration air supply part, and the low dew point air supply unit. 2. The low dew point air generator according to claim 1, comprising two four-port automatic switching valves.

  In the low dew point air generator according to the present invention, preferably, the moisture condensing unit includes a condenser for condensing and removing moisture in the processing air, a sensor for measuring the total pressure of the environment (total pressure sensor), and a high It has a temperature sensor or temperature / humidity sensor having a resolution, and a rotation speed control type blower for controlling the pressure and flow rate of the processing air.

  In the low dew point air generator according to the present invention, preferably, the moisture condensing unit further includes a two-fluid nozzle that is provided upstream of the condenser and ejects compressed air and humidified water. .

  In the low dew point air generator according to the present invention, preferably, the low dew point air supply unit has a dust removal filter using a water-repellent material and a heating mechanism for adjusting the temperature of air after temperature swing adsorption. It is characterized by that.

  Moreover, the low dew point air generator according to the present invention is preferably characterized in that the temperature swing adsorption unit has a plurality of stages of the two series of adsorbent parts in series.

  In the low dew point air generator according to the present invention, preferably, the adsorbent part of the temperature swing adsorption unit is loaded with an adsorbent containing synthetic zeolite, natural zeolite, silica gel or alumina as a main component. It is characterized by that.

  In the low dew point air generator according to the present invention, preferably, the adsorbent portion is further loaded with an adsorbent containing a solid acidic substance and / or hydrophobic zeolite and / or activated carbon as a main component. And

  Further, the low dew point air generator according to the present invention preferably has a temperature control mechanism for controlling the temperature after moisture condensation removal of the processing air based on information on the state quantity of the processing air processed by the moisture condensation unit. It is characterized by having.

  The low dew point air generator according to the present invention can generate low dew point air of −30 to −120 ° C. from air at normal temperature and atmospheric pressure.

  Further, since the low dew point air generating apparatus according to the present invention uses two 4-port automatic switching valves for switching the flow path, the energy loss generated in the adsorption rotor type dehumidifying apparatus provided with the damper type automatic valve is completely eliminated. Can be useless.

  Furthermore, since the low dew point air generator according to the present invention uses a part of the air after temperature swing adsorption for the moisture desorption process, it has been generated in the regeneration air passage and the purge air passage of the rotor type dehumidifier. Large energy losses can be greatly reduced.

  The moisture condensing unit of the low dew point air generator according to the present invention includes a sensor for measuring the total pressure of the environment, a temperature sensor or a temperature sensor having a high resolution, and a rotation speed control type blower, and a temperature swing. Since the enthalpy of the processing air obtained by condensing and removing the water flowing into the adsorption unit is adjusted to a predetermined value, a predetermined amount of predetermined low dew point air can be generated stably and reliably.

  In addition, since the two-fluid nozzle is provided on the upstream side of the condenser of the moisture condensing unit, the adsorption active interference substances in the processing air are condensed and removed in the condenser, so that low dew point air can be generated stably and reliably.

  Furthermore, since the processing air flow rate, temperature, and absolute humidity are adjusted to predetermined values, in addition to the required rise time of the conventional adsorption rotor type dehumidifier, the low dew point air supply unit according to the present invention can be shortened. Since it has a water-repellent dust removal unit, the required rise time can be further shortened.

  Further, if an adsorbent that adsorbs and removes molecular contaminants is additionally loaded on the adsorbent that adsorbs and removes moisture, high-purity low-dew point air can be supplied.

FIG. 1 is a diagram showing a schematic configuration of a low dew point air generator according to the present embodiment. FIG. 2 is a humidity diagram for explaining the dehumidifying behavior in the case of an adsorption rotor type apparatus. FIG. 3 (A) is a diagram showing a configuration of a low dew point air generation device which is a preferred aspect of the low dew point air generation device according to the present embodiment. FIG. 3 (B) is a diagram illustrating a configuration of a low dew point air generation device that is a modification of the low dew point air generation device of FIG. 3. FIG. 4 is a diagram showing a configuration of a low dew point air generating device of another modification of the low dew point air generating device of FIG. 3. FIG. 5 is a diagram showing a configuration of a low dew point air generation device according to still another modification of the low dew point air generation device of FIG. 3. FIG. 6 is a diagram showing a configuration of a moisture condensing unit of the low dew point air generating device of still another modified example of the low dew point air generating device of FIG.

  Embodiments of the present invention (hereinafter referred to as embodiments of the present invention) will be described below with reference to the drawings.

First, a low dew point air generator according to this embodiment will be described with reference to FIG. In FIG. 1, each line connecting the devices indicates an air duct and the flow of air therein, among which a solid line indicates a flow of processing air or low dew point air, and a broken line indicates a flow of regeneration air. However, in each figure after FIG. 3 (A), there is a display different from this display for convenience.
A low dew point air generator 10 according to the present embodiment shown in FIG. 1 includes a moisture condensation unit 12, a temperature swing adsorption unit 14, and a low dew point air supply unit 16.

The moisture condensation unit 12 includes a moisture condensation removal mechanism and dehumidifies the processing air. The moisture condensation and removal mechanism is preferably a mechanism that condenses and removes moisture in the air by cooling, but is not limited to this, and other mechanisms such as condensing and removing moisture in the air by compression, for example, may be used. It is not excluded. As the processing air (indicated by an arrow A in FIG. 1), ambient air at normal temperature and normal pressure can be suitably used. However, the present invention is not limited to this, and for example, circulating air that collects and recycles low dew point air after use at the supply destination may be used.
The temperature swing adsorption unit 14 has two series of adsorbent portions 18a and 18b. An appropriate moisture adsorbent is loaded in the adsorbent portions 18a and 18b. Of the two series of adsorbent parts 18a and 18b, one series is an adsorbent part for the moisture adsorption process (the adsorbent part 18a in FIG. 1), and the other adsorbent part for the moisture desorption process (FIG. 1). Then, the adsorbent portion 18b). Two series of adsorbent portions 18a and 18b are provided so as to be switchable between a moisture adsorption process and a moisture desorption process.
The temperature swing adsorption unit 14 has a regeneration air supply unit 20. The regeneration air supply unit 20 uses a part of the air after temperature swing adsorption (shown by an arrow B in FIG. 1) flowing out from the adsorbent unit used for the moisture adsorption process for the moisture desorption process. To supply. Thereby, the water | moisture content adsorbed by the adsorbent part is desorbed, and the regenerated adsorbent part is used for the moisture adsorption process. Furthermore, it is not limited to this, For example, the circulating air which collect | recovers and recycles the low dew point air after using it in the supply destination may be sufficient.
The low dew point air supply unit 16 includes a temperature adjustment mechanism, adjusts the temperature of the air after temperature swing adsorption, and supplies it to the supply destination. As the temperature adjustment mechanism, a heating mechanism that heats air can be suitably used, but not limited to this, a cooling mechanism may be used, and a heating / cooling mechanism that performs both heating and cooling as necessary is used. May be.

The low dew point air generating apparatus 10 according to the present embodiment preferably has first and second four-port automatic switching valves 22a and 22b that switch the flow path of air flowing between the connected units.
The first 4-port automatic switching valve 22a switches the flow path between the cooling / dehumidification unit 12, the two adsorbent portions 18a, 18b for the moisture adsorption process and the moisture desorption process, and the regeneration air supply unit 20. The second 4-port automatic switching valve 22b provides a flow path between the two adsorbent portions 18a and 18b, the regeneration air supply portion 20 and the low dew point air supply unit 16 for the moisture adsorption process and the moisture desorption process. Switch.
Depending on the connection conditions between the units, the automatic switching valve may be a multi-port other than four ports. Moreover, it does not exclude using a combination of a plurality of valves and pipes or ducts instead of the multi-port automatic switching valve.

A method of supplying low dew point air using the low dew point air generator 10 according to the present embodiment is as follows.
Process air is introduced into the moisture condensing unit 12 by an appropriate suction / air blowing mechanism. The processing air introduced into the moisture condensing unit 12 is cooled to a temperature of 5 ° C. using, for example, an appropriate cooling mechanism as a moisture condensation removing mechanism, and dehumidified to a saturated moisture of a temperature of 5 ° C., for example.
The air from which moisture has been condensed and removed is introduced into the adsorbent portion 18a of the temperature swing adsorption unit 14 through, for example, the first four-port automatic switching valve 22a. The air introduced into the adsorbent part 18a from which moisture has been condensed and removed is further adsorbed and removed by moisture, and may be simply referred to as a low dew point, including the case of a low dew point or an ultra low dew point (hereinafter referred to as an ultra low dew point). )
The low dew point air is introduced into the low dew point air supply unit 16 through the second 4-port automatic switching valve 22b. The low dew point air introduced into the low dew point air supply unit 16 is temperature-adjusted so as to match the temperature condition required by the supply destination and supplied to the supply destination.
Part of the air after temperature swing adsorption that flows out from the adsorbent part 18a by the regeneration air supply part 20 is the adsorbent in which the inflow of air is blocked by the first and second four-port automatic switching valves 22a and 22b. To the unit 18b. The adsorbent portion 18b, which has been previously used for the moisture adsorption process and has reduced moisture adsorption capacity, is desorbed by the inflow of air having a low dew point, and recovers (regenerates) the moisture adsorption capacity. The reduction of the moisture adsorption capacity of the adsorbent part 18a and the recovery of the moisture adsorption capacity of the adsorbent part 18b are advanced in a balanced manner, and after a predetermined time has elapsed, the first and second 4-port automatic switching valves 22a and 22b are switched. The adsorbent part 18b is provided for the moisture adsorption process, and the adsorbent part 18a is provided for the moisture desorption process.

Since the low dew point air generator 10 according to the present embodiment described above obtains the low dew point air by the temperature swing adsorption unit 14, it is not necessary to excessively pressurize the processing air, and the low dew point air is generated. Low energy consumption. Further, since the moisture condensation unit 12 and the low dew point air supply unit 16 are provided, the moisture adsorption load of the temperature swing adsorption unit 14 is reduced, and further, the moisture condensation unit 12 and the low dew point are independent of the temperature swing adsorption unit 14. Since the moisture content and temperature of the air are adjusted by the air supply unit 16, desired low dew point air can be obtained easily and reliably.
In the case of an adsorption rotor type apparatus, as shown in FIG. 2, the process air ideally changes in an isoenthalpy process. For example, the process air moves from the inlet point a where the specific enthalpy is i ₁ to the isoenthalpy line. toward the b changes over the curve represented by the solid line, should be an absolute humidity x ₁ is the target dew point. However, in actuality, since sensible heat transfer from the regeneration zone of the adsorption rotor to the dehumidification zone occurs, the curve changes on the curve represented by the broken line toward the point c where the specific enthalpy of the outlet is i ₂ , The absolute humidity is x ₂ (> x ₁ ). That is, there is a problem that the target dew point of the air after processing rises and the control of the dew point becomes complicated. In contrast, the low dew point air generator according to the present embodiment does not cause sensible heat transfer between the two series of adsorbent portions 18a and 18b corresponding to the dehumidification zone and the regeneration zone. Can be changed in an isoenthalpy process, and the control of the dew point of the low dew point air is easy.
In addition, the low dew point air generator can quickly and surely switch the fluid flow path when using the two four-port automatic switching valves 22a and 22b, so that the start-up adjustment of the device and the condition change of the supply air can be performed. It does not take a long time. This also reduces energy loss.

  Here, regarding the preferred mode of the low dew point air generation device 10 according to the present embodiment, the configuration and operation of the device will be described with reference to FIG.

  A low dew point air generator 10a shown in FIG. 3A includes a moisture condensation unit 12a, a temperature swing adsorption unit 14a, and a low dew point air supply unit 16a. In FIG. 3A, an arrow 1 indicates a processing air intake port, an arrow 2 indicates a low dew point air supply port supplied to a supply destination (use point), and an arrow 3 indicates a high temperature air discharge port described later. , Respectively.

  The moisture condensing unit 12a includes a dust filter 24, a blower 26, a condenser 28, and a heater 30 in order from the upstream side of the processing air, and these devices are connected by an air duct.

The dust removal filter 24 is a HEPA filter, for example, and removes dust in the processing air.
The blower 26 is, for example, a turbo blower of a rotational speed control system, sucks the processing air, raises the required flow pressure to, for example, about 2 to 5 kPa, and sets the flow rate to a predetermined flow rate in the range of, for example, about 100 to 150 m ³ / min. adjust.
The condenser 28 is a refrigerant evaporator of the refrigerator unit. The refrigerant evaporating pressure is manipulated by an electronic expansion valve (not shown) to control the processing air to a predetermined temperature between the processing air dew point and 4.0 ° C. For example, when processing air having a temperature of 21 ° C. and a relative humidity of 50% is allowed to flow into the condenser 28, the dew point is 10.4 ° C., so that the processing air is at a temperature between 10.4 ° C. and 4.0 ° C., For example, the temperature is controlled to 5.0 ° C. When the temperature of the processing air is 4.0 ° C. or less, while the processing air flows through the heat transfer tube group of the condenser 28, the moisture of the processing air becomes frost or ice, and the heat transfer tube is frosted or frozen to transfer the heat. In order to block the heat tube group and hinder continuous stable operation of the condenser 28, 4.0 ° C. is the lower limit of the moisture condensation temperature.
The specific enthalpy of the processing air that flows into the adsorbents 18a and 18b is, for example, the electric power from S10, which is a high-resolution (high sensitivity, high accuracy) temperature sensor, when obtaining air with a target dew point of −70 ° C. The signal is 5.00 ± 0.10 to 0.01 ° C., and the electrical signal from S12, which is a high resolution (high sensitivity, high accuracy) sensor, is described later with 7.00 ± 0.10 to 0.01 ° C. Adjust the temperature. Further, it is detected by the high resolution (high sensitivity, high accuracy) temperature sensor S14 that the air is the target dew point.
The heater 30 is, for example, a fin type heater. Since mist is inevitably contained in the processing air flowing down the condenser 13, the mist disappears by heating the processing air passing through the heater 15 to, for example, 7.00 ± 0.10 to 0.01 ° C. can do.
The moisture condensing unit 12a further includes a temperature / humidity sensor S10 after the condenser 28 and a temperature sensor S12 after the heater 30. For example, the operation of the refrigerator unit is controlled by an electrical signal from the temperature / humidity sensor S10 to adjust the temperature and humidity of the processed air after condensation. Further, for example, the operation of the heater 15 is controlled by an electric signal from the temperature sensor S12, and the temperature of the processing air after heating is adjusted. Note that it is preferable to use a temperature / humidity sensor instead of the temperature sensor S12 because the behavior of mist in the air can be grasped.

  A first four-port automatic switching valve 22a is provided at the branch point of the air duct connecting the moisture condensing unit 12a and the temperature swing adsorption unit 14a, and the air flow path is switched according to the operating conditions. In FIG. 3A, the flow path from the moisture condensing unit 12a to the adsorbent part 18a described later of the temperature swing adsorbing unit 14a is opened by the first four-port automatic switching valve 22a to the adsorbent part 18b described later. The flow path is closed.

  The temperature swing adsorption unit 14a includes two series of adsorbent portions 18a and 18b and a regeneration air supply portion 20a, and these devices are connected by an air duct.

The adsorbent portions 18a and 18b are provided with an adsorbent containing a synthetic zeolite, natural zeolite, silica gel, alumina or the like as a main component. The adsorbent is preferably processed into a honeycomb, corrugated or pleated shape.
The treated air from which moisture has been condensed and removed is introduced into the adsorbent portion 18a provided for the moisture adsorption process, and the moisture in the treated air is adsorbed and removed by the adsorbent. Thereby, low dew point air is obtained. In addition, in the adsorbent part 18a provided for the moisture adsorption process, a substantially adiabatic operation is performed, and an isoenthalpy process occurs.

  The low dew point air flowing out from the adsorbent part 18a is introduced into the low dew point air supply unit 16a via a second 4-port automatic switching valve 22b provided in an air duct connecting the adsorbent part 18a and the low dew point air supply unit 16a. Is done. In addition, a heat-resistant dust removal filter formed using an inorganic fiber such as a glass fiber or a metal fiber (not shown) can be appropriately installed at the outlet of the adsorbent portions 18a and 18b. The details of the branching portion 38a provided in the air duct will be described later.

  The low dew point air supply unit 16a includes, in order from the upstream side of the low dew point air, a dust filter 42, a blower 44, and a heater 46, and these devices are connected by an air duct. Further, a temperature sensor S18 and a dew point sensor S20 are provided on the outlet side of the heater 46.

The dust removal filter 42 of the low dew point air supply unit 16a can be applied with a filter having the same structure as the dust removal filter 24 in which the water-repellent treatment is applied to the cloth filter material, the fiber filter material, and the bag filter material. Dust that could not be removed and foreign matters that may be generated in the steps after the dust removal filter 24 are removed.
Since the filter material constituting the dust removal filter 24 is usually a material that adsorbs and retains moisture, it takes a long time before air with a predetermined low dew point can be supplied. Therefore, a water-repellent filter material is used for the dust filter 42 installed in the low dew point adsorbent unit 16a, and a predetermined low dew point air can be supplied in a short time.
The low dew point air from which the dust has been removed is pressurized to a pressure required to be supplied to the supply destination by the blower 44. In addition, as long as the air blower 44 has a predetermined | prescribed pressure | voltage rise capability, the thing of a suitable system can be used.
The increased low dew point air is introduced into a heater 46 having the same structure as the heater 36, for example, and adjusted to a temperature required by the supply destination.
The installation position of the dust filter 42 is not limited to the upstream side of the blower 44, and can be installed upstream or downstream of the heater 46 or downstream of the temperature sensor S18 or the dew point sensor S20.
The temperature-adjusted low dew point air is supplied to a supply destination indicated by an arrow 2, for example, a dry room.
In addition, while grasping | ascertaining the temperature and dew point of the low dew point air supplied to a supply destination by the temperature sensor S18 and dew point sensor S20, Preferably, the heater 46 is controlled by the electrical signal from temperature sensor S18, and low dew point air is controlled. Adjust the temperature.

On the other hand, the regeneration air supply unit 20a includes a blower 32, a preheater 34, and a heater 36 in order from the upstream side where regeneration air is introduced, and these devices are connected by an air duct. Further, temperature sensors S14 and S16 are provided in the air duct on the suction side of the blower 32 and the air duct on the outlet side of the heater 36, respectively.
By switching the three-port automatic switching valve 40 connected to the three-port automatic switching valve 40 provided at the branching portions 38a and 38b of the air ducts on the outlet side of the adsorbent portions 18a and 18b, A part of the air after temperature swing adsorption flowing out from the adsorbent part 18a or the adsorbent part 18b is supplied to the regeneration air supply part 20a. FIG. 3A shows a state in which air is supplied from the adsorbent portion 18a to the regeneration air supply portion 20a. The low dew point air flowing out from the adsorbent part 18a is distributed, for example, at a ratio of 0.25 to 1.5 for the supply to the regeneration air supply unit 20a to 1 for the supply to the low dew point air supply unit 16a. .

A part of the air after temperature swing adsorption (hereinafter, this is also referred to as regeneration air) is pressurized by the blower 32 and introduced into the preheater 34.
Air having a high temperature of, for example, about 120 to 200 ° C. discharged from the adsorbent portion 18b is introduced into the preheater 34 via the first four-port automatic switching valve 22a. The regeneration air is indirectly preheated to a temperature of, for example, 100 to 150 ° C. In addition, the arrow 3 in FIG. 3 (A) shows the discharge port of high temperature air, as demonstrated previously.
The preheater 34 is composed of, for example, a multi-tube heat exchanger or a stacked heat exchanger. The preheated regeneration air is introduced into the heater 36 and heated to a temperature of, for example, 170 to 250 ° C. by an appropriate heating source such as an oil heater.
The heated regeneration air flowing out of the heater 36 is introduced into the adsorbent part 18b through the second 4-port automatic switching valve 22b. The adsorbent adsorbing moisture in the adsorbent portion 18b is desorbed and regenerated by the regeneration air.
Regeneration air contains a small amount of molecular pollutants with a concentration of the order of ppb or less, but since regeneration air is heated to a high temperature and used for desorption of moisture, the adsorption equilibrium partial pressure of molecular pollutants is at room temperature. Since it is much lower than the adsorption equilibrium partial pressure, there is little possibility that molecular contaminants will contaminate the adsorbent part 18b. For example, when the flow rate ratio of the supply air and the regeneration air is 1: 1, the volume flow rate of the regeneration air that is thermally expanded by heating to 200 to 250 ° C. is 1.6 to 1. The heat energy necessary for desorption of the adsorbed molecular contaminants and moisture is given to the regeneration air, and the regeneration air flowing in the adsorbent can have a sufficient flow rate.
The temperature of the regeneration air is grasped by the temperature sensors S14 and S16, and preferably, the heater 36 is controlled by an electric signal from the temperature sensor S14 to adjust the temperature of the regeneration air flowing out of the heater 36. .

  If the air duct and each device constituting the temperature swing adsorption unit 14a and the low dew point air supply unit 16a are subjected to surface processing that makes it difficult for moisture to adhere to the metal surface in contact with the low dew point air, for example, fluororesin coating processing, The moisture adsorbed on the inner surface and the inner surface of each duct can be significantly reduced, which is preferable.

  According to the low dew point air generation device 10a described above, the operational effects of the low dew point air generation device 10 can be obtained more suitably.

Next, with respect to a modified example of the low dew point air generating device 10a, the configuration and operational effects of the device will be described with reference to FIG.
The low dew point air generator 10b shown in FIG. 3B differs from the low dew point air generator 10a in the configuration of some of the devices and the control system of the low dew point air generator 10b, but the rest is low. It is the same as the dew point air generator 10a, and includes a moisture condensation unit 12b, a temperature swing adsorption unit 14b, and a low dew point air supply unit 16b.
Therefore, about the structure similar to the low dew point air generator 10a of the low dew point air generator 10b, the same referential mark is attached | subjected to an apparatus etc. and the overlapping description is abbreviate | omitted.
In FIG. 3B, reference numeral 48 denotes a refrigerant compressor having a rotation speed control function not shown in FIG. 3A, and reference numeral 50 denotes electronic expansion not shown in FIG. 3A. Each valve is shown.

The low dew point air generation device 10b includes a calculation / control mechanism 100 that exchanges electrical signals with each sensor and each device, and controls the operation of each device.
The moisture condensing unit 12b further includes an atmospheric pressure sensor (total pressure sensor) S22, a flow velocity sensor S24, a temperature sensor S26, and a related humidity sensor S28.
The calculation / control mechanism 100 calculates and controls any one or more or all of the dew point of the processing air, the required cooling temperature of the processing air, the required cooling heat of the processing air, and the specific enthalpy of the processing air. By converting it into an electrical signal, the condensation temperature of the processing air is controlled so that the humidity of the supply air is surely at a desired low dew point. Further, the specific enthalpy of the processing air flowing out of the moisture condensation unit 12b is adjusted to a predetermined value by the calculation / control mechanism 100. Preferably, the electric signal from the dew point sensor S20 of the low dew point air and the electric signal from the high resolution (high sensitivity, high accuracy) temperature sensor S10 are also taken into account, taking into account the isoenthalpy change of the processing air in the adsorbent part 18a Based on this, the condensation temperature of the processing air is controlled at, for example, 5.00 ± 0.10 to 0.01 ° C.
Furthermore, the specific enthalpy of the processing air to be flowed into the temperature swing adsorption unit 14b by controlling the electrical signal from the high resolution (high sensitivity, high accuracy) temperature sensor S12 to, for example, 7.00 ± 0.10 to 0.01 ° C. Adjust to obtain target dew point air. Then, it is detected that the air is the target dew point by the high resolution (high sensitivity, high accuracy) temperature sensor S14.
Thereby, low dew point air can be obtained reliably and efficiently in the adsorbent part 18 of the temperature swing adsorption unit 14b into which the process air is introduced.

  In the temperature swing adsorption unit 14 b shown in FIG. 3B, the regeneration air supply unit 20 b further includes a cooler 52 upstream of the preheater 34. The adsorbent part 18b that has regenerated the adsorbent with the heated regeneration air is used for the adsorption treatment step after being cooled. That is, the heating of the regeneration air by the preheater 34 and the heater 36 is stopped, and the regeneration air cooled to a temperature of, for example, −30 to 10 ° C. by the cooler 52 is introduced into the adsorbent portion 18b. The agent part 18b is efficiently cooled in a short time and used for the adsorption process. Moreover, the heat-resistant dust removal filter which is not shown in figure which was mentioned above can be suitably installed in the outflow port of adsorbent part 18a, 18b.

In the low dew point air supply unit 16b shown in FIG. 3 (B), the electrical signal obtained from the temperature sensor S18 is sent to the calculation / control mechanism 100 and adjusted to the temperature required in the supply destination indicated by the arrow 2, for example, the dry room. It is converted into a control signal for the heater 46.
In addition, the atmospheric pressure that fluctuates by 10 to 50 hPa between seasons and days affects the mass flow rate and specific enthalpy of the processing air, the regeneration heat amount and regeneration time of the adsorbent (adsorbent heating time, desorption time, adsorbent cooling time). Therefore, the measurement value obtained by the atmospheric pressure sensor S22 is input to the calculation / control mechanism 100. In addition, the installation position of the dust removal filter 42 created using the water-repellent filter material is not limited to the upstream side of the blower 44, but the upstream side or the downstream side of the heater 46 or the temperature sensor S18 or the dew point sensor S20. It can be installed downstream.

  According to the low dew point air generation device 10b of the modified example of the low dew point air generation device 10a described above, the operational effects of the low dew point air generation device 10a can be obtained more suitably.

Next, with respect to another modified example of the low dew point air generating device 10a, the configuration and operational effects of the device will be described with reference to FIG.
The low dew point air generator 10c shown in FIG. 4 has a device configuration and control system substantially similar to the low dew point air generator 10b, and includes a moisture condensing unit 12c, a temperature swing adsorption unit 14c, and a low dew point air supply unit 16c. Is provided. Therefore, about the structure similar to the low dew point air generator 10b of the low dew point air generator 10c, the same referential mark is attached | subjected to an apparatus etc. and the overlapping description is abbreviate | omitted. Also, a description of a heat-resistant dust filter (not shown) that can be appropriately installed at the outlets of 18a-2 and 18b-2 is omitted.
The low dew point air generator 10c may have the same control system configuration as the low dew point air generator 10a.

The low dew point air generation device 10c is different from the adsorbent portions 18a and 18b of the low dew point air generation device 10b in the configuration of the adsorbent portions 18a-2 and 18b-2 of the temperature swing adsorption unit 14c.
The adsorbent portions 18a-2 and 18b-2 are provided with adsorbents in multiple layers. That is, the adsorbent parts 18a-2 and 18b-2 are loaded with adsorbents such as synthetic zeolite and natural zeolite used for the adsorbent parts 18a and 18b, respectively, and further, titanium, silicon and / or zirconium or vanadium. A solid acidic substance which is a binary to ternary complex oxide composed of the above and an adsorbent composed of hydrophobic zeolite or activated carbon are stacked and loaded.
In the air taken in as treated air, a wide variety of basic, organic, and acidic molecular pollutants derived from the use of chemicals that occur with the atmosphere, human body, and industrial activities are on the order of ppm to ppb. It is mixed. Therefore, molecular contaminants are removed from the dry clean room, dry clean booth, dry clean mini-environment, or the work space inside the manufacturing equipment that requires a dry and clean atmosphere, and a predetermined low dew point. A large supply of dehumidified air is required. For example, in production lines such as lithium ion batteries and organic thin film solar cells, there is a precision coating process that uses a basic organic solvent in a dry atmosphere, so a large amount of air adjusted to a low dew point and high purity is used. It is necessary to supply.
The adsorbent composed of synthetic zeolite, natural zeolite or the like adsorbs and removes water having a large partial pressure contained in the processing air. Further, among the molecular pollutants contained in the processing air, the basic component is adsorbed and removed by an adsorbent composed of a solid acidic substance, and the organic or acidic component is adsorbed composed of a hydrophobic zeolite or activated carbon. Is done. Of the molecular contaminants, basic components include ammonia and amines, organic components include toluene and cinna, and acidic components include NO _x , SO _x , and organic acids. It is done.

Conventionally, the collection and removal of these molecular contaminants in the processing air has been performed by a chemical filter (chemical adsorption filter). A chemical filter is made by impregnating a cloth-like filter material with an acidic or basic agent, or by adding an ion exchange group to a fibrous filter material, or by attaching a pleat to a cloth-like filter material and sewing it into a bag. Is filled with ion exchange resin or activated carbon. However, chemical filters have a limited time of use, and replacement with new ones is inevitable, so it is necessary to stop the operation of the low dew point air generator in order to replace the chemical filter, At this time, there is a possibility that air in the surrounding environment containing moisture close to% order enters the inside of the low dew point air generator. Furthermore, the chemical filter inherently holds a large amount of adhering moisture, and in the use stage, moisture is generated by a neutralization reaction between the acid and the base and becomes a moisture generating source.
According to the adsorbent parts 18a-2 and 18b-2, there is no possibility of causing the above-described problem that may occur by using a chemical filter.

  According to the low dew point air generation device 10c of the modified example of the low dew point air generation device 10a described above, the effects of the low dew point air generation device 10a can be obtained more suitably, and molecules contained in the processing air can be further obtained. The contaminants can be removed efficiently.

Next, with respect to still another modified example of the low dew point air generating device 10a, the configuration and operational effects of the device will be described with reference to FIG.
A low dew point air generator 10d shown in FIG. 5 has a device configuration and control system substantially the same as the low dew point air generator 10b, and includes a moisture condensing unit 12d, a temperature swing adsorption unit 14d, and a low dew point air supply unit 16d. Is provided. Therefore, about the structure similar to the low dew point air generator 10b of the low dew point air generator 10d, the same referential mark is attached | subjected to an apparatus etc. and the overlapping description is abbreviate | omitted. Also, a description of a heat-resistant dust removal filter (not shown) that can be appropriately installed at the outlet of the adsorbent portions 18a-ii and 18b-ii will be omitted.
The low dew point air generator 10d may have the same control system configuration as the low dew point air generator 10a.

The low dew point air generator 10d is different from the temperature swing adsorption unit 14b of the low dew point air generator 10b in the configuration of the temperature swing adsorption unit 14d.
The temperature swing adsorption unit 14d of the low dew point air generator 10d has a plurality of stages (two stages in FIG. 6) of two series of adsorbent portions provided in a switchable manner. That is, the adsorbent part 18a-ii is provided downstream of the adsorbent part 18a-i, the adsorbent part 18b-ii is provided downstream of the adsorbent part 18b-i, and an adsorbent that adsorbs moisture is loaded. .

The air duct connecting the adsorbent part 18a-i and the adsorbent part 18a-ii and the air duct connecting the adsorbent part 18a-ii and the adsorbent part 18b-i have 4-port automatic switching valves 22c and 22d, respectively. Provided.
One outflow port of each of the four-port automatic switching valves 22c and 22d is connected to two inflow ports of the four-port automatic switching valve 22e via a branch air duct. The other outflow ports of the 4-port automatic switching valves 22c and 22d are connected to the inflow port of the 3-port automatic switching valve 54a through different branch air ducts. The outflow port of the 3-port automatic switching valve 54a is connected to the inflow port of the 4-port automatic switching valves 22c, 22d via the air duct, and the outflow port of the 4-port automatic switching valve 22c, 22d is the adsorbent part through the air duct. 18a-ii, 18b-ii.
A cooling unit 56 is provided between the 4-port automatic switching valve 22e and the 3-port automatic switching valve 54a via an air duct.
The cooling unit 56 includes a blower 58 and a cooler 60, and each device is connected by an air duct. The cooling unit 56 is provided with a dew point sensor S30 and a temperature sensor S32.

The processing air flowing out of the moisture condensing unit 12 passes through the adsorbent portion 18a-i and adsorbs and removes moisture. The low dew point air whose temperature has risen to, for example, 20.5 ° C. by the heat of adsorption is sucked into the blower 58 through the 4-port automatic switching valve 22c and the 4-port automatic switching valve 22e. The low dew point air pressurized by the blower 58 is cooled by the cooler 60 to a temperature of, for example, 10 to −30 ° C. At this time, the temperature of the low dew point air flowing out of the cooler 60 is adjusted by the electrical signals of the dew point sensor S30 and the temperature sensor S32.
For example, when the adsorbent parts 18a-i and 18a-ii are used for the adsorption process, the low dew point air flowing out of the cooler 60 passes through the 3-port automatic switching valve 54a and the 4-port automatic switching valve 22c. It is introduced into the adsorbent part 18a-ii.
In addition, a flow path of high-temperature regenerated air used for the desorption process of the adsorbent part 18b-ii is provided via a 3-port automatic switching valve 54b provided adjacent to the 4-port automatic switching valve 22e. Mutual mixing of the low-temperature cooling air and the high-temperature regeneration air is prevented.

The cooled low dew point air introduced into the adsorbent part 18a-ii passes through the adsorbent part 18a-ii and further becomes a low dew point.
A regeneration air supply unit 20d is provided between the adsorbent units 18a-ii and 18b-ii. The heated regeneration air that flows out of the regeneration air supply unit 20d passes through the adsorbent units 18b-ii and 18b-i in series to regenerate the adsorbents of the adsorbent units 18b-ii and 18b-i.

  According to the low dew point air generation device 10d of the modified example of the low dew point air generation device 10a described above, the operational effects of the low dew point air generation device 10a can be obtained more suitably.

Next, the configuration and operational effects of the apparatus will be described with respect to still another modified example of the low dew point air generator 10a.
The modified low dew point air generating device not shown in the figure has an apparatus configuration and a control system substantially similar to the low dew point air generating device 10d.
In the modified low dew point air generator, the adsorbent parts 18a-2 and 18b-2 of the low dew point air generator 10c are used as the adsorbent parts 18a-ii and 18b-ii of the low dew point air generator 10d. The point differs from the low dew point air generator 10d.

  According to the low dew point air generating device of the above modification, the operational effect of the low dew point air generating device 10a can be obtained, and the operational effect of the low dew point air generating device 10c can also be obtained.

Next, with respect to still another modified example of the low dew point air generating device 10a, the configuration and operational effects of the device will be described with reference to FIG.
The low dew point air generator of the modification shown in FIG. 6 is different from the other examples in the moisture condensing unit. The modified low dew point air generator can use any of the low dew point air generators 10, 10a, 10b, 10c, and 10d as the temperature swing adsorption unit and the low dew point air supply unit.

The moisture condensation unit 12e of the modified low dew point air generator shown in FIG. 6 further includes a two-fluid nozzle portion 62 upstream of the condenser 28.
The two-fluid nozzle unit 62 includes a two-fluid nozzle 64 provided in an air duct connecting the blower 26 and the condenser 28, a humidifying (humidifying) water pump 66 and a small air compressor 68 connected to the two-fluid nozzle 64. Prepare. In FIG. 6, reference numeral 70 denotes a dust filter, and reference numeral 72 denotes a humidification (humidification) water tank.
As the humidifying water (humidifying water) stored in the humidifying water tank 72, pure water is used at least, but ultrapure water is required in the field of semiconductor manufacturing such as LSI and VLSI, and the impurity content is on the order of ppb or less. May be required. The water quality required for the field will be selected. In semiconductor manufacturing, high purity ultrapure water from which fine particles, viable bacteria, organic matter, silica and the like are sufficiently removed in addition to the electrolyte directly related to the resistivity according to the degree of integration is used.

The humidified water (humidification water) in the humidified water tank 72 is sucked by the humidified water pump 66 and sent to the two-fluid nozzle 64. On the other hand, compressed air is fed into the two-fluid nozzle 64 using a small air compressor 68. The compressed air and the humidified water are ejected from the two-fluid nozzle 64 as a large number of fog droplets (fogs). In other words, the processing air is surely adiabatic cooled as soon as it is humidified, and is in a water supersaturated state, and the generated mist droplets are sent to the condenser 28 along with the processing air without disappearing.
Generation of mist droplets using 1.0 to 1.2 times the amount of adiabatic cooling water required to saturate the process air with moisture by humidified adiabatic cooling is far more than the number of mist droplets due to the amount of water under unsaturated conditions. Since a large number of mist droplets are generated, and the water evaporates from the mist droplets until the saturates from the unsaturation to saturation, the mist droplet diameter decreases. Therefore, each mist droplet has a specific surface area larger than that in the unsaturated condition, and the surface area of the total number of mist droplets becomes enormous. For this reason, a large number of mist droplets collide with contaminant molecules in the processing air between the two-fluid nozzle 64 and the condenser 28, take them into the mist droplets, and efficiently collect the contaminants. it can. In particular, HF, HCl, F ⁻ , Cl ⁻ , F ₂ , Cl ₂ , H ₂ S and adsorbing activity interference substances represented by organosilicon compounds such as silylating agents and silane coupling agents have high solubility in water. Therefore, it is dissolved in the mist droplets together with the collision, reaches the condenser 28 in a state of being dissolved in the mist droplets, and the mist droplets are removed by the condenser 28.
At this time, using the measurement value obtained by the measurement mechanism including the atmospheric pressure sensor S22, the flow velocity sensor S24, the temperature sensor S26, and the related humidity sensor S28, 1 of the amount of the adiabatic cooling water necessary to saturate the process air by humidified adiabatic cooling. The calculation / control mechanism 100 calculates 0.0 to 1.2 times the amount of humidified water. The humidified water is automatically supplied to the two-fluid nozzle 64 by using the humidified water pump 66 that is activated by the control signal obtained by converting the calculated value.

  According to the moisture condensation unit 12e of the low dew point air generator of the modified example described above, it is possible to suitably process the processing air containing the adsorption activity interfering substance. Moreover, by this, the activity of the adsorbent in the adsorbent part of the temperature swing adsorption unit can be stably maintained over a long period of time.

10, 10a, 10b, 10c Low dew point air generator 12, 12a, 12b, 12c, 12d, 12e Moisture condensing unit 14, 14a, 14b, 14c, 14d Temperature swing adsorption unit 16, 16a, 16b, 16c, 16d Low dew point Air supply unit 18a, 18b, 18a-1, 18b-2, 18a-i, 18a-ii, 18b-i, 18b-ii Adsorbent part 20 Regeneration air supply part 22a First 4-port automatic switching valve 22b First Second 4-port automatic switching valve 22c, 22d, 22e 4-port automatic switching valve 24, 42, 70 Dust filter 26, 32, 44, 58 Blower 28 Condenser 30, 36, 46 Heater 34 Preheater 38a, 38b Branch 40, 54a, 54b 3-port automatic switching valve 48 Refrigerant compressor 50 Electronic expansion 52, 60 cooler 56 cooling unit 62 two-fluid nozzle unit 64 two-fluid nozzle 66 humidifying water pump 68 the air compressor 72 humidifying water tank 100 arithmetic and control mechanism

Claims (9)

A moisture condensing unit that condenses and removes moisture in the processing air, a temperature swing adsorption unit that adsorbs and removes moisture that has been condensed and removed by temperature swing, and a low temperature that is adjusted to supply the air after temperature swing adsorption to the supply destination With dew point air supply unit,
The temperature swing adsorption unit has two series of adsorbent parts for the moisture adsorption process and the moisture desorption process provided so that the inflow flow path of the processing air can be switched, and flows out from the adsorbent part used for the moisture adsorption process. A low dew point air generator comprising: a regeneration air supply unit configured to supply a part of the air after temperature swing adsorption to an adsorbent unit used for a moisture desorption process.   2. The two-port automatic switching valve for switching a flow path between the moisture condensing unit, the two series of adsorbent parts, the regeneration air supply part, and the low dew point air supply unit. The low dew point air generator described.   The moisture condensing unit condenses and removes moisture in the processing air, a sensor for measuring the total pressure of the environment, a temperature sensor or a temperature / humidity sensor having high resolution, and a rotation for controlling the pressure and flow rate of the processing air. The low dew point air generator according to claim 1 or 2, further comprising a number-control blower.   4. The low dew point air generator according to claim 3, wherein the moisture condensing unit further includes a two-fluid nozzle that is provided upstream of the condenser and ejects compressed air and humidified water.   2. The low dew point air generator according to claim 1, wherein the low dew point air supply unit has a dust removing filter using a water repellent one and a heating mechanism for adjusting the temperature of air after temperature swing adsorption.   2. The low dew point air generator according to claim 1, wherein the temperature swing adsorption unit has a plurality of stages of the two series of adsorbent portions in series.   The low dew point air generator according to claim 1, wherein the adsorbent part of the temperature swing adsorption unit is loaded with an adsorbent containing synthetic zeolite, natural zeolite, silica gel or alumina as a main component.   8. The low dew point air generating device according to claim 7, wherein the adsorbent part is further loaded with an adsorbent containing a solid acidic substance and / or a hydrophobic zeolite and / or activated carbon as a main component.   2. A low dew point air generator according to claim 1, further comprising a temperature control mechanism for controlling a temperature after moisture condensation and removal of the processing air based on information on a state quantity of the processing air processed by the moisture condensing unit. .

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