JP5294191B2 - Wet desiccant air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out low temperature regeneration of an absorbent, to drastically reduce energy consumption, and to prevent increase of the energy consumption due to drastic increase of pressure loss and corrosion of a metal member due to splashing of the absorbent. <P>SOLUTION: The wet desiccant air conditioner is composed of a dehumidification unit 3 equipped with a gas-liquid contact structure 6 having a multiplicity of air current passages, a liquid splashing/spraying means 7 arranged on a top face of the gas-liquid contact structure 6 for supplying the absorbent by absorbing moisture in air by contact with the air, and a liquid receiving tank 8 storing the absorbent discharged from a lower face of the gas-liquid contact structure 6, and a regeneration unit 5 equipped with a feed pump 10 and a circulation passage 11 for supplying and circulating the absorbent stored in the liquid receiving tank 8 to the liquid splashing/spraying means 7, and a membrane separation device 12 carrying out membrane separation of the moisture from the absorbent in a middle of the circulation passage 11 to regenerate the absorbent. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a wet desiccant air conditioner that dehumidifies treated air with an absorbing liquid that absorbs moisture in the air by contact with air, and in particular, a wet desiccant air conditioner that achieves low-temperature regeneration and significant energy saving of the absorbing liquid. Related to the machine.

  In recent years, the size of a mother glass substrate used for manufacturing a flat panel display and an increase in the size and capacity of a manufacturing apparatus due to an increase in the diameter of a wafer used for manufacturing a semiconductor have progressed. There is a tendency to increase the size of the manufacturing plant buildings.

  With the increase in the scale of such manufacturing factories, energy consumption is increasing due to the increased capacity of air conditioning in the factories. In particular, in clean rooms for manufacturing electronic devices, about 40% of the energy consumed by the entire factory is energy required for air conditioning, and about 46% of the air conditioning energy is spent on outside air treatment. The accompanying increase in energy consumption (absolute amount) is inevitable. Therefore, the energy saving of the energy required for the air conditioning treatment of the introduced outside air, particularly the reduction of the energy required for the latent heat treatment is an important issue.

On the other hand, a dehumidifying unit that absorbs and removes moisture in the air by contacting the absorbing liquid such as lithium chloride with circulating air, and a regenerating unit that concentrates and regenerates the absorbing liquid used in the dehumidifying unit. A wet desiccant air conditioner is known (for example, Patent Document 1 below). In the dehumidifying unit, dehumidification is performed in which the absorbing liquid is sprayed on the flow path of the desiccant air conditioner so that the air and the absorbing liquid are brought into direct contact with each other and moisture in the air is absorbed by the absorbing liquid.
JP 2004-92956 A

  However, in the conventional wet desiccant air conditioner, as described in Patent Document 1, the absorbing liquid is sprayed to directly contact the air and the absorbing liquid, or the absorbing liquid is sprayed on a metal or resin filler. In general, the method of making contact between the air and the absorbing liquid is generally used, and the carry-over phenomenon of the absorbing liquid mist occurs due to the direct spraying of the absorbing liquid and the limit of the wettability of the filler. was there. For this reason, in conventional wet desiccant air conditioners, it is necessary to install a mist removing member (eliminator) on the downstream side of the dehumidifying unit, which increases the pressure loss of the air conditioner and increases the size of the air conditioner. There was a problem of increased energy. In addition, when a lithium chloride aqueous solution is used as the absorbing solution, the scattered mist is a cause of corrosion of the metal member.

  Furthermore, in a conventional wet desiccant air conditioner, a heating method for evaporating moisture by heating the absorbing liquid is generally used as a method for regenerating the absorbing liquid in the regeneration unit. For this reason, in the conventional wet desiccant air conditioner, a heating device such as a heater or a boiler for heating the absorption liquid is indispensable. In order to evaporate moisture by heating in this way, in addition to the latent heat of evaporation of water, which is the theoretically required minimum energy, heat energy for heating the absorbing liquid itself to the evaporation temperature of water is used as the heating energy. In addition, since it is necessary to supplement the heat energy for the heating and heat loss of the housing, a large amount of heat energy is consumed. In general, in a desiccant air conditioner, the ratio (primary energy efficiency) of the primary energy input to the enthalpy difference between the air before and after the treatment is a small value of less than 1.0. Considering this, it can be estimated that the energy consumed to evaporate the moisture from the absorbing liquid is about four times the evaporation latent heat of water, which is the minimum energy required. As a result, there is a problem that effective use of energy cannot be achieved unless high-temperature exhaust heat of about 100 ° C. is used. Therefore, a technique that does not rely on heating to regenerate the absorbing liquid has been desired.

  Then, the main subject of this invention is providing the wet desiccant air conditioner which reduced the energy consumption significantly by making low temperature reproduction | regeneration of absorption liquid as a 1st subject. A second problem is to provide a wet desiccant air conditioner that does not cause an increase in energy consumption due to a significant increase in pressure loss and corrosion of a metal member due to scattering of absorbing liquid.

In order to solve the above-mentioned problem, as the present invention according to claim 1, a gas-liquid contact structure having a large number of air flow passages, and an upper surface of the gas-liquid contact structure are arranged. A dehumidifying unit comprising a spray / spray means for supplying an absorbing liquid that absorbs moisture, a liquid receiving tank for storing the absorbing liquid discharged from the lower surface of the gas-liquid contact structure, and a liquid receiving tank A circulation path and a feed pump for supplying and circulating the stored absorption liquid to the spraying / spraying means, and membrane separation for regenerating the absorption liquid by membrane separation from the absorption liquid in the middle of the circulation path A gas-liquid contact structure having a large number of air flow passages, a spray / spray means for supplying water or a sterilizing deodorant to the upper surface of the gas-liquid contact structure, and the gas-liquid The water or sterilization discharged from the lower surface of the contact structure A liquid receiving tank for storing odorant, a circulation path for supplying and circulating the water or sterilizing deodorant stored in the liquid receiving tank to the spraying / spraying means, and a liquid feed pump; Consisting of an air conditioning unit installed downstream of the unit ,
The gas-liquid contact structure is formed by alternately laminating corrugated plates having different wave directions, opening both front and rear surfaces and both upper and lower surfaces, introducing process air from the front opening, and treating air from the rear opening. It is a gas-liquid contact structure with a skewed honeycomb structure that discharges
A plurality of the gas-liquid contact structures of the slanted honeycomb are arranged in series with respect to the flow path, and the gas-liquid contact structure located on the most downstream side matches the set humidity of the air supplied to the room. The procedure of supplying the absorption liquid at a concentration close to the concentration of the absorption liquid in an equilibrium state and supplying the absorption liquid stored in the liquid receiving tank to the gas-liquid contact structure on the upstream side is repeated in order, After the absorption liquid stored in the liquid receiving tank on the side is sent to the regeneration unit for regeneration, it is supplied again to the gas-liquid contact structure on the most downstream side ,
In the membrane separation device, a permeate-side channel that allows moisture to permeate through the membrane from the absorbent-side channel through which the absorbent circulates is formed, and a plurality of vacuum pumps are serially connected to the permeate-side channel. And the permeate side flow path is depressurized by the vacuum pump, and the water vapor pressure of the permeate side flow path is set to be high on the upstream side of the absorption liquid side flow path and low on the downstream side. And
In the dehumidifying operation in summer, the treated air is dehumidified by the dehumidifying unit, then air-conditioned by the air conditioning unit, and then supplied indoors.
In the humidification operation in winter, the treated air passes through the dehumidifying unit, and is humidified with water at room temperature in the slanted honeycomb of the air conditioning unit, and then supplied to the room, and then the wet desiccant An air conditioner is provided.

  In the first aspect of the present invention, since the absorption liquid regenerating apparatus in the regeneration unit is provided with a membrane separation apparatus that regenerates the absorption liquid by separating the water from the absorption liquid that has passed through the dehumidifying unit. Like a wet desiccant air conditioner, the absorption liquid can be regenerated without heating, and the absorption liquid can be regenerated at a low temperature. In addition, since energy for heating is unnecessary, energy consumption can be greatly reduced.

  Further, as a dehumidifying unit, a gas-liquid contact structure having a large number of air flow passages and supply means for supplying an absorption liquid that absorbs moisture in the air by contact with air to the gas-liquid contact structure. Because the absorption liquid supplied from the supply means flows down the surfaces of the many air flow passages of the gas-liquid contact structure, the contact between the processing air and the absorption liquid is performed efficiently. become.

  In the present invention, as the gas-liquid contact structure, corrugated plates having different corrugated directions are alternately stacked, both front and rear surfaces and upper and lower surfaces are opened, and processing air is introduced from the front opening, and the rear opening A gas-liquid contact structure having a skewed honeycomb structure in which the treated air is discharged from

  The above-mentioned gas-liquid contact structure having a skewed honeycomb structure particularly includes the air-cooled skew honeycomb described in JP-A-2003-202174, JP-A-2003-202191, etc. It is used as a body. By using this gas-liquid contact structure of the skewed honeycomb, the gas-liquid contact efficiency can be remarkably improved. In addition, unlike conventional wet desiccant air conditioners, the absorption liquid mist carryover phenomenon due to the direct spraying of the absorption liquid into the air and the wettability limit of the filler does not occur, so the pressure associated with the installation of the eliminator The problem of increased loss and further increased energy consumption can be solved, and the problem of corrosion of the metal member due to scattered absorbing liquid mist does not occur.

Further, a gas-liquid contact structure having a number of air flow passages downstream of the dehumidification unit, a spray / spray means for supplying water or a sterilizing deodorant to the upper surface of the gas-liquid contact structure, and the gas-liquid A liquid receiving tank for storing the water or sterilizing deodorant discharged from the lower surface of the contact structure, and supplying the water or sterilizing deodorant stored in the liquid receiving tank to the spraying / spraying means for circulation. An air conditioning unit including a circulation path and a liquid feed pump is added .

  By adding the air conditioning unit downstream of the dehumidifying unit, air having a higher degree of air conditioning can be supplied into the room, and the air is composed of a gas-liquid contact structure having a number of air flow passages. By using an adjustment unit, energy consumption for this air adjustment was reduced.

Furthermore, in the membrane separation device, a permeate-side flow channel that allows moisture to permeate through the membrane from the absorbent-side flow channel through which the absorption liquid flows is formed, and a vacuum pump is serially connected to the permeate-side flow channel. Provided in multiple stages, the permeation side flow path is depressurized by the vacuum pump, and the water vapor pressure of the permeation side flow path is set high on the upstream side of the absorption liquid side flow path and low on the downstream side Has been .

In membrane separation, by providing in series in a multistage vacuum pump, reducing the power of the vacuum pump, Fig energy saving Rutotomoni, the amount of moisture absorbing liquid that is fed to the membrane separation device, the absorbing liquid Considering the fact that there are many in the upstream of the side channel and few in the downstream, the water vapor pressure of the permeate side channel is set to be high on the upstream side of the absorption liquid side channel and low on the downstream side, thereby reducing the vacuum. The power of the pump can be suppressed to the minimum necessary, and the energy consumption can be further reduced.

  According to a second aspect of the present invention, there is provided the wet desiccant air conditioner according to the first aspect of the present invention, wherein the membrane separation device regenerates the absorbing solution by a membrane distillation method or a pervaporation method.

  The invention according to claim 2 prescribes a preferable method of membrane separation in the membrane separation apparatus. When the membrane separation method is the membrane distillation method or the pervaporation method, an efficient and compact process can be performed, and the absorbent can be regenerated at a relatively low cost.

As the present invention according to claim 3 , a porous film having water repellency or a laminated film using a hygroscopic inorganic material typified by zeolite as a surface layer is used as the film. A wet desiccant air conditioner according to any one of 1-2 is provided.

The invention described in claim 3 prescribes a preferable form of the separation membrane. In the membrane distillation method, a porous membrane having water repellency is used. In the pervaporation method, moisture absorption typified by a hydrophilic polymer material or zeolite is used. It is preferable to use a laminated film using a conductive inorganic material as a surface layer.

As the present invention according to claim 4 , as the absorbing solution, an organic aqueous solution selected from the group of triethylene glycol, tetraethylene glycol, glycerin or the like, or a group of lithium chloride, lithium bromide, lithium iodide, calcium chloride, etc. The wet desiccant air conditioner according to any one of claims 1 to 3, wherein an inorganic aqueous solution selected from the above is used.

As the present invention according to claim 5 , in the membrane separation device, a permeate-side flow channel that allows moisture to permeate through the membrane from the absorbent-side flow channel through which the absorbent is circulated, and the permeate-side flow channel direct contact methods such as water vapor pressure is lower than the water vapor pressure of the absorption liquid, the gas gap method, vacuum method, to claim 1-4 or the means selected from the group of sweep gas method is used The described wet desiccant air conditioner is provided.

  As described above in detail, according to the present invention, the absorption liquid can be regenerated at a low temperature, and the energy consumption can be greatly reduced. Furthermore, it is possible to provide a wet desiccant air conditioner that does not cause an increase in energy consumption due to a significant increase in pressure loss and corrosion of metal members due to scattering of the absorbing liquid.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Structure of Wet Desiccant Air Conditioner 1 According to First Embodiment]
FIG. 1 is a flow path configuration diagram of a wet desiccant air conditioner 1 (hereinafter referred to as a desiccant air conditioner) according to a first embodiment of the present invention.

  As shown in the illustrated example, the desiccant air conditioner 1 includes a blower 2, a dehumidifying unit 3 that dehumidifies circulating air with an absorbing liquid that absorbs moisture in the air by contact with air, and a cooling coil 4 that cools the circulating air. And a regenerating unit 5 that regenerates the absorbing liquid, and adjusts the humidity of the processing air sent by the blower 2 and supplies it to the room.

  As the absorbing solution, it is preferable to use an organic aqueous solution such as triethylene glycol, tetraethylene glycol, or glycerin or an inorganic aqueous solution such as lithium chloride, lithium bromide, lithium iodide, or calcium chloride. In particular, as a result of experiments, triethylene glycol, tetraethylene glycol and lithium chloride are preferably used because they are excellent in the non-permeability of the membrane 13 described later.

(Structure of dehumidifying unit 3)
The dehumidifying unit 3 is configured by alternately laminating corrugated plates having different wave directions, opening both front and rear surfaces and upper and lower surfaces, introducing processing air from the front opening, and discharging processed air from the rear opening. A gas-liquid contact structure 6 having a skewed honeycomb structure, a spray means 7 for spraying the absorbing liquid on the upper surface of the gas-liquid contact structure 6, and a lower surface of the gas-liquid contact structure 6. The liquid receiving tank 8 stores the discharged absorbing liquid, and in the process in which the processing air passes through the gas-liquid contact structure 6, moisture in the processing air is brought into contact with the processing air and the absorbing liquid. Dehumidification is performed by being absorbed by the absorbing liquid.

  As the gas-liquid contact structure 6, a gas-liquid contact structure (hereinafter referred to as a skewed honeycomb) used in an air cooling device described in JP 2003-202174 A, JP 2003-202191 A, or the like. Is used as is. Hereinafter, the skewed honeycomb 6 will be described with reference to the description of the publication. The skewed honeycomb 6 has a waveform having a waveform that propagates in one direction as shown in FIGS. 2 and 3. A plurality of sheets 6A and 6B (hereinafter, also referred to as “corrugated sheets”) are laminated to form a honeycomb shape, and the corrugated sheets 6A and 6B that are laminated are inclined in the wave propagation direction every other sheet. And the honeycomb-like structures are arranged so that the wave propagation directions of every two layers are substantially the same.

  The oblique honeycomb 6 is cut by four faces 6a to 6d perpendicular to the faces parallel to the corrugated sheets 6A and 6B to form a rectangular parallelepiped, and the cut face is a wave propagation direction of the corrugated sheets. If the rectangular parallelepiped is placed with one of the cut surfaces 6d as the lower surface and the outermost layers 6b and 6c of the corrugated sheet as the left and right surfaces, respectively, The four sides of the front and rear surfaces 6b, 6c and the upper and lower surfaces 6a, 6d are all open with honeycomb cells, and the left and right surfaces 6e, 6f are closed with corrugated sheets. That is, the skew honeycomb 6 has a structure in which the front and rear surfaces 6b and 6c and the upper and lower surfaces 6a and 6d are opened. Further, for example, the front and rear surfaces 6b and 6c of the cut surface are formed with cells extending obliquely upward and cells extending obliquely downward. The oblique angle (symbol X in the figure) with respect to the inflow and outflow direction (horizontal direction) of air when viewed from the front and rear surfaces of the cell extending in the oblique direction is usually 15 to 45 degrees, preferably 25 to 35 degrees. Within range. It is preferable that the oblique angle is within this range because the flow velocity is in an appropriate range and the contact efficiency is improved.

  In the skewed honeycomb 6, the angle (in the drawing, Y) in which the wave propagation directions of the laminated corrugated sheets intersect each other is usually 30 to 90 degrees, preferably 50 to 70 degrees. When the corrugated sheets are laminated so as to intersect within the above angle range, when the oblique angle (X) is set to 15 to 45 degrees as described above, the processing air and the absorbing liquid are substantially separated from the honeycomb cells. This is preferable because the contact area between the processing air and the absorbing liquid is increased. That is, as will be described later, the processing air is introduced from the front opening 6b of the skewed honeycomb 6, and the absorbing liquid is supplied from the top opening 6a by the spraying means 7, and permeates the corrugated sheet of the skewed honeycomb. In addition, since the extremely surface of the corrugated sheet slowly flows downward, the flow direction of the treatment air and the flow direction of the absorbing liquid on the permeation wall surface are maintained at an appropriate angle, and the contact efficiency is increased.

  The height of the cells of the skewed honeycomb 6, that is, the height of the cell showing the dimension between the corrugated peaks and valleys is usually 2.5 to 8.0 mm, preferably 3 to 5 mm. If the height of the cell is less than 2.5 mm, it is difficult to manufacture and the pressure loss increases, which is not preferable. Further, if the height of the cell exceeds 8.0 mm, the contact efficiency decreases, which is not preferable.

  The cell width in the state of the corrugated sheet of the skew honeycomb 6, that is, the cell pitch is usually 6 to 16 mm, preferably 7 to 10 mm. Further, the dimension between the front opening 6b and the rear opening 6c of the skewed honeycomb 6, that is, the thickness (t) of the skewed honeycomb is usually 100 to 1000 mm, preferably 200 to 800 mm. If the thickness is less than 100 mm, it is not preferable because the contact efficiency is lowered, and if the thickness exceeds 1000 mm, the contact efficiency is not further improved, and the pressure loss is increased. In addition, the thickness of the skewed honeycomb 6 may be a total thickness within the above range when a plurality of skewed honeycombs are used. For example, when a skewed honeycomb having a thickness of 300 mm is used, three skewed honeycombs having a thickness of 100 mm may be stacked in the thickness direction so that the total thickness is 300 mm. When the skewed honeycomb 6 is used as the gas-liquid contact structure, the contact efficiency per volume is high, so that the thickness of the skewed honeycomb can be reduced and the installation space of the apparatus can be reduced. Furthermore, the circulation amount of the absorbing liquid can be reduced, and a significant energy saving can be achieved.

  The sheet-like member constituting the skewed honeycomb 6 has an uneven surface and a porous inside, and it is possible to increase the surface area of the element, and to absorb the absorbing liquid and air that permeate and flow down the element. This is preferable in that the contact area is increased. As such a sheet-like member, for example, from one or more fillers or binders selected from the group consisting of alumina, silica and titania, and a fiber substrate such as glass fiber, ceramic fiber or alumina fiber The thing which becomes. Among these, those containing titania are preferable because the removal efficiency of acidic chemical contaminants is improved. The sheet-like member usually contains 60 to 93% by weight of filler or binder and 7 to 40% by weight of fiber base material, preferably 70 to 88% by weight of filler or binder and fiber base material. Contains 12-30% by weight. It is preferable that the blending ratio of the sheet-like member is within the above range because the liquid permeability and strength of the sheet-like member are high.

  The sheet-like member can be produced by a known method, for example, a paper made of glass fiber, ceramic fiber or alumina fiber is immersed in a slurry in which a binder such as alumina sol and a filler such as alumina hydrate are mixed. Then, it can be obtained by drying and corrugating, followed by drying and heat treatment to remove moisture and organic components. When silica or titania is contained in addition to alumina, for example, the blending amount of silica and titania is usually 5 to 40 parts by weight with respect to 100 parts by weight of alumina.

  Further, the skew honeycomb 6 has a sheet-like member having a thickness of usually 200 to 1000 μm, preferably 300 to 800 μm. The porosity of the skewed honeycomb 6 is usually 50 to 80%, preferably 60 to 75%. By setting the porosity within the above range, moderate permeability can be realized, and the contact efficiency between the air and the absorbing liquid can be increased. When the sheet-like member has the above thickness and porosity, the liquid gas ratio and the liquid permeation rate are in an appropriate range, and the contact efficiency between the absorbing liquid and air is increased and the strength is sufficient. The height of the skew honeycomb 6 is 200 to 800 mm, preferably 400 to 600 mm.

  As a method of forming the sheet-like member into a corrugated sheet, there is a method using a known corrugator in which a flat sheet is passed between a plurality of wide gears having corrugated irregularities that oscillate in the radial direction. Can be mentioned. As a method for forming the skewed honeycomb 6 from the obtained corrugated sheet, for example, first, the corrugated sheet is 100 mm long (thickness dimension after forming the skewed honeycomb) × 800 mm wide (after forming the skewed honeycomb). A rectangular corrugated sheet is arranged and cut so that the wave propagation direction is 15 to 45 degrees with respect to one side of the rectangular shape with respect to a rectangular cutting die having a width dimension or height dimension). A method of producing and then arranging the obtained rectangular corrugated sheets so that every other wave has a wave propagation direction obliquely and adhering them to each other is mentioned. In addition, when manufactured in this way, the thickness of one skewed honeycomb is the vertical length of the cutting die. For this reason, for example, when the thickness of the skewed honeycomb 6 incorporated in the dehumidifying unit 3, that is, the dimension between the front opening 6b and the rear opening 6c of the skewed honeycomb 6 is required to be 300 mm, the length is 100 mm. When using a skewed honeycomb having a thickness of 100 mm manufactured by the above cutting type, three skewed honeycombs may be stacked in the thickness direction. In addition, when the size of one skewed honeycomb 6 in the height direction or the width direction is insufficient, a plurality of the skewed honeycombs 6 may be stacked in the height direction or arranged in the width direction. In addition, in the case of using a plurality of such stacked or arranged in a row, the skewed honeycombs 6 may or may not be bonded. In the case where the bonding is not performed, it is only necessary to arrange a plurality of skew honeycombs 6 so as to overlap each other.

  By the way, the higher the concentration of the absorbing liquid dripped onto the skewed honeycomb 6, the smaller the amount of moisture in the absorbing liquid, so that the dehumidifying amount can be earned. On the other hand, when the absorbing liquid has a high concentration, When the amount of the absorbing liquid itself is the same, the amount of dripping is reduced, so that the gas-liquid contact efficiency is poor and the dehumidifying amount is reduced. In order to avoid such a problem, the amount of the absorbing solution itself must be increased. Therefore, problems such as high cost and increased energy consumption for performing advanced regeneration processing may occur. Therefore, in the desiccant air conditioner 1, the absorbing liquid is supplied at a concentration close to the concentration of the absorbing liquid that is in an equilibrium state enough to meet the set humidity of the air supplied to the room. In practice, it is desirable to supply an absorbing solution having a slightly higher concentration than the equilibrium state in consideration of the absorption rate and the like.

  As shown in FIG. 4, the skewed honeycomb 6 may have a plurality of (in the illustrated example) four skewed honeycombs 6, 6. In this case, first, the absorption liquid in the equilibrium state is supplied to the skewed honeycomb 6 located on the most downstream side, and the absorbent stored in the liquid receiving tank 8 is supplied to the skewed honeycomb 6 on the upstream side. Repeat the procedure sequentially. This makes it possible to fully utilize the moisture absorption performance possessed by the absorbent. Then, the absorbing liquid stored in the most upstream liquid receiving tank 8 is sent to the regeneration unit 5 for regeneration, and is supplied again to the most downstream skewed honeycomb 6.

  Further, as shown in FIG. 5, in the skewed honeycomb 6, the flow path may be formed in the vertical direction so that the air flow direction and the absorbing liquid dropping direction are opposed to each other. As a result, the contact time between the processing air and the absorption liquid is increased, so that the contact efficiency is increased, and the moisture absorption performance possessed by the absorption liquid can be fully utilized.

  Any means may be used as the spraying means 7 as long as the liquid can be sprayed or dropped evenly. For example, a water supply duct in which a large number of dripping holes are formed may be used, or a spray nozzle is attached to the liquid supply pipe for spraying, or a tank bottom surface is used as a perforated plate for spraying. May be. In addition, since the said absorption liquid is used as a spray, it is desirable to manufacture with a member with high chemical resistance. Further, it is preferable that the spraying means 7 is capable of adjusting the amount of water so that the minimum amount of absorbing liquid is supplied to the skewed honeycomb 6. Further, the absorbing liquid may be supplied to the skewed honeycomb 6 by spraying means instead of the spraying means 7. The liquid spraying means 7 may be provided with a replenishing means for replenishing the absorbing liquid.

  The liquid receiving tank 8 receives and stores the absorbing liquid discharged from the lower surface opening 6d of the skewed honeycomb 6. Although it does not specifically limit as a form of the liquid receiving tank 8, For example, the box-shaped liquid receiving pan etc. with which the upper surface opened are mentioned.

(Structure of cooling coil 4)
The cooling coil 4 performs heat exchange with circulating air by circulating a heat medium (fluid) that exchanges heat with cooling water, ground water, or underground heat cooled by a refrigerator or a cooling tower (not shown). Is. The cooling coil 4 is provided to cool the outside air to a predetermined room temperature and to cool the air slightly heated by the absorbed heat of moisture after passing through the dehumidifying unit 3. Specifically, in the desiccant air conditioner 1, cold water of about 12 ° C. to 20 ° C. is circulated in the cooling coil 4. This cold water of 12 ° C to 20 ° C requires a cold water extraction temperature higher than that of a freezer that produces cold water of 7 ° C, so it is cooled by a freezer that can operate at a high COP or a cooling tower that uses natural energy of the atmosphere. Heated medium (fluid) that exchanges heat with the cooled cooling water, groundwater, or underground heat can be used. For this reason, it is possible to significantly reduce energy consumption for cooling the air.

(Structure of playback unit 5)
As shown in FIG. 1, the regeneration unit 5 includes a circulation path 11 and a liquid feed pump 10 for supplying and circulating the absorbing liquid stored in the liquid receiving tank 8 to the spraying means 7, and a circulation path. 11 is composed of a membrane separation device 12 that regenerates the absorbent by separating the moisture from the absorbent, and separates and removes only the moisture from the absorbent that has absorbed the moisture of the processing air by the skewed honeycomb 6. To do.

  In the membrane separator 12, the absorbent is regenerated using a membrane distillation method or a pervaporation method. In each of the separation methods, an absorption liquid side flow path and a permeation side flow path through which the absorption liquid flows through the membrane 13 are formed in the middle of the circulation path 11, and water in the absorption liquid is vaporized to form water vapor. The permeation side flow path through the membrane 13 is permeated and collected.

  The membrane distillation method uses a porous membrane that allows gas and vapor to permeate but not liquid, and uses a vapor pressure difference between the fluid flowing through the absorbent-side channel and the fluid flowing through the permeate-side channel as a driving force. It is. As shown in FIG. 6, the membrane distillation method is roughly classified into (A) direct contact method, (B) gas gap method, (C) decompression method, and (D) sweep gas method. In the direct contact method, a high-temperature absorption liquid and a low-temperature permeate (water) are directly interposed through the membrane 13, and the water vapor evaporated from the absorption liquid permeates through the through-hole portion of the membrane due to the difference in water vapor pressure between the two. In this method, the liquid is condensed by the permeated liquid and absorbed by the permeated liquid to regenerate the absorbed liquid. In the gas gap method, the pressure reduction method, and the sweep gas method, the permeate-side flow path is made into a gas phase, and the water vapor pressure in the gas phase is made lower than that of the absorbing liquid, so that absorption is performed in the same manner as the direct contact method. The liquid is regenerated.

  As the membrane 13 used in the membrane distillation method, a porous membrane having water repellency such as PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), PP (polypropylene), PE (polyethylene), or a water-repellent treatment. The porous membrane is preferably used. As shown in FIG. 7, these membranes have (A) a spiral structure (see the product catalog of Nitto Denko Corporation), (B) a pleated structure (see JP 2000-42379), (C) a hollow fiber structure or Installed in the membrane separator 12 as a membrane module such as a tube structure (see Nitto Denko's product catalog), (D) plate and frame structure (lamination of flat membranes) (see Nitto Denko's product catalog) . As shown in FIG. 7 (A), the spiral structure is a module in which flat membranes are rolled up, and a water collecting pipe that penetrates the central portion while the absorbing liquid flows axially between the flat membranes. Permeate is collected. In the pleated structure, as shown in FIG. 7B, a pleated membrane element is mounted between the inner cylindrical member and the outer cylindrical member, and the pleated membrane element is accommodated in the top housing and the bottom housing. Thus, the moisture of the absorption liquid supplied from the liquid supply port provided in the upper part of the top housing permeates the pleated membrane element and is separated and recovered. In the hollow fiber structure or the tube structure, as shown in FIG. 7 (C), a large number of hollow fiber membranes are accommodated in a cylindrical housing, and moisture is hollowed out from the absorbent flowing through the outer periphery of the hollow fiber membrane. It is permeated into the thread membrane and separated and recovered. In the plate and frame structure, as shown in FIG. 7 (D), a plurality of plate-like films with films attached to both sides of the plate substrate are superposed, and the absorbing solution is circulated above or below the plate-like film. Openings are provided alternately, and when the absorbing liquid flows on the surface of the plate-like membrane, it is transmitted through the plate substrate side and separated and recovered.

  Of these membrane modules, a spiral structure having a large membrane area per unit volume, a compact size, and excellent permeability is desirable. The pore diameter of the porous membrane is preferably 0.2 μm or less.

  The pervaporation method forms an absorption liquid side channel through which the absorption liquid flows through the membrane 13 and a permeation side flow path consisting of a gas phase or a liquid phase, and selectively transfers moisture in the absorption liquid to the permeation side. It is to be transmitted. As the membrane 13 used in the pervaporation method, one having a laminated structure in which a surface layer made of a hydrophilic nonporous active layer and a support layer made of a porous layer or a nonwoven fabric layer are laminated is preferably used. . As the non-porous active layer of the surface layer, a hydrophilic polymer material such as PVA (polyvinyl alcohol) or a hygroscopic inorganic material such as zeolite can be used. These membranes have the same structure as the above-mentioned membrane distillation method. (A) Spiral structure, (B) Pleated structure, (C) Hollow fiber structure or tube structure, (D) Plate and frame structure (flat membrane shown in FIG. Is installed in the membrane separation device 12 as a membrane module.

  The method for regenerating the absorbing solution by the regeneration unit 5 will be specifically described by taking regeneration by the reduced pressure method as an example among the membrane distillation methods. Note that the method described below can be similarly applied to the direct contact method, the gas gap method, and the sweep gas method. The membrane 13 has a surface layer made of a porous membrane and a water-repellent non-woven fabric so that it can withstand the liquid feeding pressure on the absorbent side and the vacuum pressure on the permeate side during use, or the strength that can withstand handling during production. It is set as the laminated structure on which the support layer which consists of etc. was laminated | stacked. The membrane 13 is disposed in the membrane module with the surface layer as the absorbing liquid side and the support layer as the permeate side. The saturated water vapor pressure of the absorption liquid flowing through the membrane module is determined by the temperature and concentration of the absorption liquid, and generally the water vapor pressure increases as the temperature on the absorption liquid side increases or decreases. At this time, the differential pressure between the saturated water vapor pressure on the absorption liquid side and the vacuum pressure on the permeation side becomes a driving force, and only the water vapor in the absorption liquid permeates the membrane 13 and is separated to the permeation side, and the absorption liquid is dehydrated. It has become so.

  In order to depressurize the permeation side flow path, air (gas) in the permeation side flow path is forcibly removed by the vacuum pump 14. At this time, as the vacuum pump 14, it is preferable to use a dry pump having a small resistance of a driving unit such as a shaft. Thereby, motive power is reduced and energy saving can be achieved.

Here, the theoretical power _PW of the vacuum pump can be reduced by increasing the number of stages of the vacuum pump (increasing m), as is apparent from the theoretical formula of the following formula (1). The pump is preferably provided in multiple stages in series.

ここで、Ｐ_Ｗ：真空ポンプの理論動力、Ｐ_１：吸入圧、Ｐ_２：吐出圧（大気圧）、Ｑ_１：排気速度（吸入状態）、κ：比熱比、ｍ：段数、η_tad：全断熱圧縮効率、η_ｍ：機械効率

Here, P _W : theoretical power of vacuum pump, P ₁ : suction pressure, P ₂ : discharge pressure (atmospheric pressure), Q ₁ : exhaust speed (suction state), κ: specific heat ratio, m: number of stages, η _tad : Total adiabatic compression efficiency, η _m : Mechanical efficiency

  Furthermore, the amount of moisture in the absorbent that is sent to the regeneration unit 5 is large upstream of the absorbent-side flow path, and gradually decreases as the moisture in the absorbent is separated to the permeate side as it goes downstream. ing. Therefore, in order to keep the water vapor permeation amount per unit area of the membrane constant, it is preferable that the water vapor pressure of the permeation side flow path is high on the upstream side and low on the downstream side. As described above, in the present membrane separation device 12, the permeation-side vacuum pressure can be varied in accordance with the concentration of water in the absorption liquid, so that efficient membrane separation can be performed with the power of the minimum vacuum pump. Can be realized.

[Structure of wet desiccant air conditioner 1 'according to the second embodiment]
In the desiccant air conditioner 1 ′ according to the second embodiment, as shown in FIG. 9, after the process air is dehumidified and cooled by the dehumidifying unit 3 and the cooling coil 4, various air adjustments are performed by the air adjusting unit 20 before being supplied to the room. Is planned. The air conditioning unit 20 includes a skewed honeycomb 21 having the above-described skewed honeycomb structure, a sprinkling means 22 for spraying a sterilizing deodorant such as water or chlorine dioxide water on the upper surface of the skewed honeycomb 21, and the skewed A water receiving tank 23 for storing the water or sterilizing deodorant discharged from the lower surface of the honeycomb 21, and supplying the water or sterilizing deodorant stored in the water receiving tank 23 to the watering means 22 for circulation. It comprises a circulation path 25 and a liquid feed pump 24, and performs evaporative cooling, humidification, sterilization and / or deodorization treatment in the process of passing the air after the dehumidification cooling through the skewed honeycomb 21. Although not shown, the water receiving tank 23 may be provided with replenishing means for replenishing the water or the sterilizing deodorant.

[Operation status of wet desiccant air conditioner 1, 1 ']
Next, the operation state of the desiccant air conditioners 1 and 1 ′ according to the first embodiment and the second embodiment will be described in detail based on the air diagram shown in FIG.

  In the desiccant air conditioner 1 according to the first embodiment, the air condition at each point in (a), (b), and (c) of FIG. 1 is (a), (b), and (c) of FIG. As shown in That is, when the processing air (outside air 34 ° C., 20.4 kg / kgDA, state (a)) is introduced into the desiccant air conditioner 1, it is dehumidified by the dehumidifying unit 3 to be in the state (b). After being cooled to state (c), it is supplied indoors.

  Further, in the desiccant air conditioner 1 ′ according to the second embodiment, the air condition at each point in (a), (d), (e), and (f) of FIG. As shown in (d), (e), and (f). That is, when the same processing air (state (a)) is introduced into the desiccant air conditioner 1 ′, it is dehumidified by the dehumidifying unit 3 to be in the state (d) and cooled by the cooling coil 4 to be in the state (e). Then, after the air is adjusted by the air adjusting unit 20 to be in the state (f), the air is supplied indoors.

  On the other hand, in the heating and humidifying operation in winter when the processing air is in a low-temperature and low-humidity condition, the outside air passes through the dehumidifying unit 3 and is preheated by medium-temperature water heated by heat exhaust heat such as device cooling water or heat exhaust, After being humidified with water at about room temperature, water-soluble gas removal, and sterilization and / or deodorization treatment with a sterilization deodorant in the row honeycomb, it is supplied indoors.

It is a channel lineblock diagram of wet desiccant air conditioner 1 concerning the 1st example of the present invention. 3 is a partial perspective view of a gas-liquid contact structure 6. FIG. 4 is a partially exploded view of the gas-liquid contact structure 6. FIG. It is a flow-path block diagram which shows the other example of a dehumidification unit 3 (the 1). It is a flow-path block diagram which shows the other example of a dehumidification unit 3 (the 2). It is a schematic diagram which shows the classification | category of the membrane distillation method and the pervaporation method. It is a schematic diagram which shows the classification | category of a membrane module. 3 is a flow path configuration diagram showing an example of a form of a regeneration unit 5. FIG. It is a flow-path block diagram of the wet desiccant air conditioner 1 which concerns on the 2nd form example of this invention. It is an air line figure of the wet desiccant air conditioner concerning the present invention.

  1. 1 '... wet desiccant air conditioner, 2 ... blower, 3 ... dehumidifying unit, 4 ... cooling coil, 5 ... regeneration unit, 6 ... gas-liquid contact structure (slanting honeycomb), 7 ... spraying means, 8 ... Receiving tank, 10 ... liquid feeding pump, 11 ... circulation path, 12 ... membrane separation device, 13 ... membrane, 14 ... vacuum pump

Claims (5)

A gas-liquid contact structure having a number of air flow passages, and a spray / spray means disposed on the upper surface of the gas-liquid contact structure for supplying an absorbing liquid that absorbs moisture in the air by contact with air; A dehumidification unit comprising a liquid receiving tank for storing the absorbing liquid discharged from the lower surface of the gas-liquid contact structure, and supplying the absorbing liquid stored in the liquid receiving tank to the spraying / spraying means. A regeneration unit including a circulation path and a liquid feed pump for circulation, a membrane separation device for regenerating the absorption liquid by separating the water from the absorption liquid in the middle of the circulation path, and a large number of air flow paths A gas / liquid contact structure, a spray / spray means for supplying water or a sterilizing deodorant to the upper surface of the gas / liquid contact structure, and the water or sterilizing deodorant discharged from the lower surface of the gas / liquid contact structure. The liquid receiving tank to be stored and the liquid receiving tank Said water or sterilizing deodorizer and a circulation path and liquid feed pump for supplying circulating the dispersion liquid / spray means is made up of a installed air conditioning unit downstream of the dehumidifying unit,
The gas-liquid contact structure is formed by alternately laminating corrugated plates having different wave directions, opening both front and rear surfaces and both upper and lower surfaces, introducing process air from the front opening, and treating air from the rear opening. It is a gas-liquid contact structure with a skewed honeycomb structure that discharges
A plurality of the gas-liquid contact structures of the slanted honeycomb are arranged in series with respect to the flow path, and the gas-liquid contact structure located on the most downstream side matches the set humidity of the air supplied to the room. The procedure of supplying the absorption liquid at a concentration close to the concentration of the absorption liquid in an equilibrium state and supplying the absorption liquid stored in the liquid receiving tank to the gas-liquid contact structure on the upstream side is repeated in order, After the absorption liquid stored in the liquid receiving tank on the side is sent to the regeneration unit for regeneration, it is supplied again to the gas-liquid contact structure on the most downstream side ,
In the membrane separation device, a permeate-side channel that allows moisture to permeate through the membrane from the absorbent-side channel through which the absorbent circulates is formed, and a plurality of vacuum pumps are serially connected to the permeate-side channel. And the permeate side flow path is depressurized by the vacuum pump, and the water vapor pressure of the permeate side flow path is set to be high on the upstream side of the absorption liquid side flow path and low on the downstream side. And
In the dehumidifying operation in summer, the treated air is dehumidified by the dehumidifying unit, then air-conditioned by the air conditioning unit, and then supplied indoors.
In the humidification operation in winter, the treated air passes through the dehumidifying unit, and is humidified with water at room temperature in the slanted honeycomb of the air conditioning unit, and then supplied to the room, and then the wet desiccant air conditioner.   The wet desiccant air conditioner according to claim 1, wherein the membrane separator regenerates the absorbent by a membrane distillation method or a pervaporation method.   The wet film according to any one of claims 1 to 2, wherein a porous film having water repellency or a laminated film using a hygroscopic inorganic material typified by zeolite as a surface layer is used as the film. Desiccant air conditioner.   As the absorbing solution, an organic aqueous solution selected from the group of triethylene glycol, tetraethylene glycol, glycerin or the like, or an inorganic aqueous solution selected from the group of lithium chloride, lithium bromide, lithium iodide, calcium chloride or the like is used. The wet desiccant air conditioner according to any one of claims 1 to 3. In the membrane separation device, a permeate-side channel that allows moisture to permeate through the membrane from the absorbent-side channel through which the absorbent circulates is formed, and the water vapor pressure of the permeate-side channel is the water vapor of the absorbent The wet desiccant air conditioner according to any one of claims 1 to 4 , wherein means selected from the group consisting of a direct contact method, a gas gap method, a decompression method, and a sweep gas method are used.

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