JP2000346396A - Method and device for dehumidification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for dehumidification realizing a high COP and high cooling effect of treated air. SOLUTION: A dehumidification method includes a first step of introducing outside air OA and adsorbing the moisture in the air OA with a desiccant 103, a second step of cooling the outside air OA from which the moisture is adsorbed in the first step by evaporating the operating refrigerant of a heat pump HP1 by using the outside air as the low heat source of the pump HP1, and a third step of supplying the outside air cooled in the second step to an air-conditioning space 101. The method also includes a fourth step of heating the air from the space 101 by condensing the operating refrigerant of the pump HP1 by using the air as the high heat source of the pump HP1, a fifth step of restoring the desiccant 103 which adsorbs the moisture in the first step by using the heated in the fourth step, and a sixth step of causing heat exchange between the refrigerant condensed in the fourth step and the air from the air- conditioning space 101. When the heat exchange is caused between the refrigerant and air from the space 101, heat is removed from the refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dehumidifying method and a dehumidifying apparatus, and more particularly to a dehumidifying method and a dehumidifying apparatus for dehumidifying processing air supplied to an air-conditioned space.

[0002]

2. Description of the Related Art As shown in FIG. 4, there has been a so-called desiccant air conditioning system using a heat pump as a heat source.

In this air conditioning system, a compression heat pump HP using a compressor 260 is used as a heat pump.

[0004] This air conditioning system has a desiccant rotor 1
The process air A has a route of the treated air A in which moisture is adsorbed by the heat source 03 and a route of the regeneration air B which is heated by the heating source, passes through the desiccant rotor 103 after the moisture adsorption, and desorbs and regenerates moisture in the desiccant. An air conditioner having a sensible heat exchanger 104 between the treated air to which moisture has been adsorbed and the regenerated air before regenerating the desiccant (desiccant) of the desiccant rotor 103 and before being heated by the heating source; A compression heat pump HP;
In P, the regeneration air is used as a high heat source, and the regeneration air is heated by the heater 220 to regenerate the desiccant,
The processing air is cooled by the cooler 210 using the processing air as a low heat source of the compression heat pump HP.

The sensible heat exchanger 104 and the heater 220
And a heat exchanger 121 for regenerating air between the regenerating air and the regenerating air exiting the desiccant rotor 103 is provided to save energy.

Here, the operation of the desiccant air conditioner will be described with reference to FIG. In the figure, the alphabet K in the circle
P and Q to X indicate the state of air.

In the figure, the processing air (state K) from the air-conditioned space 101 is blown by a blower 102 to a desiccant rotor 103.
Where the moisture is adsorbed by the desiccant to lower the absolute humidity, the dry bulb temperature is raised by the heat of adsorption of the desiccant to reach the state L, and the sensible heat exchanger 10
At 4, the air is cooled in the state M while the absolute humidity is kept constant, and enters the cooler 210. Here, the air is further cooled at a constant absolute humidity to become air in the state N, and humidified by the humidifier 105 to lower the dry-bulb temperature to become air in the state P, and is returned to the air-conditioned space 101. On the other hand, the outside air in the state Q is sent to the sensible heat exchanger 104 by the blower 140, where it is heated to be in the state R by cooling the processing air, and enters the heat exchanger 121 and is further heated. To the state S, and to the state T by being heated by the heater 220,
By regenerating the desiccant by the desiccant rotor 103, the absolute humidity is high, the dry-bulb temperature is lowered, and the state U is reduced.
By heating the regenerated air in the heat exchanger 121, the temperature of the dry bulb itself is lowered, and the air becomes the state V, and the exhaust air E
X is done.

[0008]

According to the conventional heat pump described above, the enthalpy difference indicating the cooling effect of the refrigerant per unit weight is determined by the enthalpy of the saturated gas line at the evaporation pressure of the refrigerant and the enthalpy of the saturated gas at the condensation pressure. It is a difference from the enthalpy of the line and is not necessarily large, so that the coefficient of performance COP of the compression heat pump HP is low, and the desiccant air conditioner (dehumidifier) using such a heat pump HP
Again, the COP had to be low.

Further, there is a limit to the temperature of the processing air supplied to the cooler 210. Therefore, an object of the present invention is to provide a dehumidifying method and a dehumidifying apparatus which have a high COP and a high cooling effect of processing air.

[0010]

In order to achieve the above object, a method for dehumidifying air according to the first aspect of the present invention is to introduce outside air OA using, for example, an apparatus shown in FIG. A first step of adsorbing the moisture in the desiccant 103; and using the outside air having the water adsorbed in the first step as a low heat source of the heat pump HP1, evaporating the working refrigerant of the heat pump HP1 with the outside air to cool the outside air. A second step of supplying outside air cooled in the second step to the air-conditioned space 101; and operating the heat pump HP1 with the air from the air-conditioned space 101 as a high heat source of the heat pump HP1. The fourth step of condensing the refrigerant and heating the air
The fifth step of regenerating the desiccant 103 adsorbed in the first step with the air heated in the fourth step; the refrigerant condensed in the fourth step and the air from the air-conditioned space 101 And a sixth step of exchanging heat.

[0011] With this configuration, since a third step is provided, dehumidification is performed using outside air as processing air, and the processing air is supplied to the air-conditioned space. That is, fresh outside air is supplied to the air-conditioned space. In addition, since the sixth step is provided, the refrigerant exchanges heat with air from the air-conditioned space, and the refrigerant liquid is typically deprived of heat and supercooled.

Here, as described in claim 2, claim 1
In the method for dehumidifying air described in the above, the moisture is adsorbed in the first step and the air from the air-conditioned space before being cooled in the second step and the air from the air-conditioned space before being heated in the fourth step. Thus, a seventh step of exchanging heat may be provided.

[0013] Further, as described in claim 3, claim 1
Alternatively, in the method for dehumidifying air according to claim 2, the air from the air-conditioned space 101 used for heat exchange with the refrigerant in the sixth step, typically used for supercooling, is supplied to the heat pump HP1. An eighth step of condensing and heating the working refrigerant of the heat pump HP1 with the air as a part of the high heat source may be provided. The air used as a part of the high heat source in the eighth step may be mixed with the air used as the high heat source in the fourth step.

In order to achieve the above object, a dehumidifier according to a fourth aspect of the present invention comprises, as shown in FIG. 1, for example, an outside air introduction path 124; and moisture in the outside air introduced through the outside air introduction path 124. A moisture adsorbing device 103 having a desiccant for adsorbing water; provided on the downstream side of the flow of the outside air with respect to the moisture adsorbing device 103, and configured to cool the outside air adsorbed by the desiccant by evaporating a refrigerant. Cooler 210; supply path 111 for introducing outside air cooled by cooler 210 into air-conditioned space 101;
A booster 260 for increasing the pressure of the refrigerant evaporated in the cooler 210
A heater for heating air from the air-conditioned space 101 by condensation of the pressurized refrigerant,
03, a heater 220 provided upstream of the flow of air from the air-conditioned space 101; and a heat exchanger 280 for exchanging heat between the refrigerant condensed by the heater 220 and the air from the air-conditioned space 101. . Typically, the refrigerant condensed by the heater 220 is cooled by air from the air-conditioned space 101.

[0015] Further, as described in claim 5, claim 4
In the dehumidifier described in the above, the moisture adsorber 103 and the cooler 2
A second heat exchanger 104 for exchanging heat between the outside air flowing between the air conditioner 10 and the air from the air-conditioned space 101 before being heated by the heater 220 may be provided.

Further, as described in claim 6, claim 5
In the dehumidifying apparatus described in the above, the air subjected to heat exchange in the heat exchanger 280 bypasses the second heat exchanger 104 and is introduced into the heater 220 by bypass paths 125B and 126B.
May be provided.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or corresponding members are denoted by the same or similar reference numerals, and duplicate description is omitted.

Referring to FIG. 1, the configuration of a dehumidifying air conditioner (air conditioning system) according to a first embodiment of the present invention will be described. In this air conditioning system, the humidity of the processing air is reduced by a desiccant (drying agent), and the air-conditioned space 101 to which the processing air is supplied is maintained in a comfortable environment.

In the drawing, along the path of the processing air A, a path 107 for introducing outside air OA used as processing air, a blower 102 for circulating the processing air, a path 108, and a moisture adsorbing device filled with desiccant. Desiccant rotor 103, path 109, heat exchanger 104 as a second heat exchanger for exchanging heat between the processing air and the regeneration air, path 110, cooler (evaporator as viewed from the refrigerant) 210, path 111, and air conditioning The space 101 is arranged in this order. Each path connects the element devices before and after the path so that the processing air communicates. The heat exchanger 104
In the figure, it is shown as a rotary heat exchanger. This may be a cross-flow heat exchanger.

Along the path of the regeneration air B, a path 124 for introducing air from the air-conditioned space 101 to the air-conditioned space used as regeneration air, a blower 140 for circulating the regeneration air, a path 125A, and a desiccant rotor 103 Heat exchanger 1 for exchanging heat between regenerated air before entering and treated air
04, path 126A, heater (condenser as seen from refrigerant)
220, path 127, desiccant rotor 103, path 1
28 and are arranged in this order, and are configured to exhaust exhaust EX.

The path 125A is branched into a path 125B, and is configured to join a path 126A via a heat exchanger 280 for exchanging heat between the regeneration air and the refrigerant and a path 126B. Paths 125B, 126
B is a path for allowing the regeneration air to flow through the heat exchanger 280 while bypassing the heat exchanger 104. In this embodiment, the refrigerant flowing through the heat exchanger 280 is a refrigerant liquid as described later, and the refrigerant liquid is supercooled by the regeneration air. That is, the heat exchanger 280 functions as a refrigerant subcooler (subcooler).

The regenerated air passing through the heat exchanger 280 passes through a path 126B indicated by a solid line in FIG.
Instead of merging with 6A, path 1 indicated by a broken line in the figure
It may be configured to exhaust directly from the heat exchanger 280 through 26C.

Next, the refrigerant path will be described with reference to FIG. Along the path of the refrigerant from the evaporator 210, the path 2
05, the compressor 260 for compressing the refrigerant evaporated and gasified in the refrigerant evaporator 210, the path 201, the refrigerant condenser 22
0, the path 202, the subcooler 280, the path 203, the throttle 270, and the path 204 are arranged in this order, and return to the refrigerant evaporator 210 again.

The desiccant rotor 103 has a rotating shaft AX1
It is formed as a thick disk-shaped rotor that rotates around, and the rotor is filled with a desiccant with a gap through which gas can pass. For example, a large number of tubular drying elements are bundled so that the central axis is parallel to the rotation axis AX1. This rotor 1
Numeral 03 is configured to rotate in one direction around the rotation axis AX1.

The flow path of the processing air A and the flow path of the regeneration air B include a plane including the rotation axis AX 1, and a partition plate whose end is provided close to the thickness direction surface of the desiccant rotor 103. , And the processing air A and the regeneration air B flow in and out in parallel with the rotation axis AX1. Thus, each drying element is connected to the rotor 1
As 03 rotates, it is arranged so as to alternately contact the processing air A and the regeneration air B.

In such an apparatus, typically, the processing air A and the regenerating air B flow in a substantially half area of the circular desiccant rotor 103 in a counterflow manner in parallel with the rotation axis AX1. It is configured.

Since the heat exchanger 104 must pass a large amount of regeneration air, the desiccant rotor 1
The structure is similar to that of No. 03, and a rotary heat exchanger filled with a heat storage material having a large heat capacity is used in place of the drying element. The rotary heat exchanger 104 rotates around the rotation axis AX2.

Referring to the psychrometric chart of FIG. 2 and the structure of FIG. 1 as needed, the operation of the dehumidifying air conditioner of the first embodiment and the dehumidifying of the present invention will be described. The method will be described. In the figure, alphabet symbols K to
N, Q, R, TU, X, and Y indicate the state of air in each section. This symbol corresponds to the circled alphabet in the flowchart of FIG.

First, the flow of the processing air A will be described. In FIG. 2, the outside air (state K) used as the processing air is:
The air is sucked by the blower 102 through the processing air path 107 and is sent to the desiccant rotor 103 through the processing air path 108.

Here, the treated air reaches the state L by absorbing moisture by the desiccant in the drying element to lower the absolute humidity and increasing the dry bulb temperature by the heat of adsorption of the desiccant. This air is sent to the heat exchanger 104 through the processing air path 109, where it exchanges heat with the regeneration air guided from the air-conditioned space 101 while keeping the absolute humidity constant, and is cooled to form M air. The vessel 210 is entered. Here, the air is further cooled at a constant absolute humidity to be in the state N. This air is dried and cooled, and is supplied to the air-conditioned space 101 via the duct 111 as the processing air SA having an appropriate humidity and an appropriate temperature.

Next, the flow of the regeneration air B will be described. In FIG. 2, the regeneration air (state Q) from the air-conditioned space 101 is:
The air is sucked in by the blower 140 through the regeneration air path 124 and sent to the heat exchanger 104 through the path 125A. Here, heat exchange is performed with the processing air (air in the state L) whose temperature has increased through the desiccant rotor 103 to increase the dry-bulb temperature to become air in the state R. This air passes through path 126
Through A, it is fed into a heater 220 where it is heated by a refrigerant that condenses (eg, at 65 ° C.) to raise the dry bulb temperature and become air in state T (eg, 60 ° C.).

This air is sent to the desiccant rotor 103 through a path 127, where the desiccant in the drying element is deprived of water, that is, desorbed and regenerated, thereby increasing the absolute humidity and increasing the desiccant. The dry-bulb temperature is lowered by the heat of moisture desorption to reach the state U.
This air is exhausted EX through the path 128.

The regeneration air in the state Q passes through the path 125B to the subcooler 280, where it cools the refrigerant liquid, and is heated to the state S, where the air is supplied to the path 126B.
To the heater 220 through the
Exhausted through 6C. FIG. 2 shows a case where the air is sent to the heater 220, and the air in the state S and the air in the state R are mixed to become the state X. The state X air is heated 220
Sent to. The rest is as described above.

In the air conditioner as described above, the amount of heat added to the regeneration air for regeneration of the desiccant of the device is represented by ΔH, as can be seen from the cycle on the air side shown in the psychrometric chart of FIG. The amount of heat pumped from the air is Δq, compressor 2
Assuming that the driving energy of 60 is Δh, ΔH = Δq + Δ
h. The cooling effect ΔQ obtained as a result of the regeneration with the heat quantity ΔH increases as the temperature of the air (state Q) to be heat-exchanged with the treated air (state L) after the adsorption of moisture is lower. That is, it becomes larger as ΔQ−Δq becomes larger in the figure. As can be understood from the present embodiment, the air in the state Q is supplied to the air-conditioned space 101.
Because it is air from the outside, the temperature is lower than that of the outside air.
Therefore, the cooling effect can be significantly increased.

Referring now to the flowchart of FIG.
The operation of the heat pump HP1 will be described. In FIG. 1, the refrigerant evaporated by the evaporator 210 is sent to the refrigerant compressor 260.
The refrigerant gas compressed by the refrigerant compressor 260 is supplied to the pipe 2
It is led to a condenser (regeneration air heater) 220 via 01. The temperature of the refrigerant gas compressed by the compressor 260 is increased by the heat of compression, and this heat heats the regeneration air. The refrigerant gas itself is deprived of heat, deprived of sensible heat and condensed after becoming saturated.

The refrigerant outlet of the heater 220 is connected to the subcooler 2
80 is connected to the refrigerant inlet of the sub-cooler 280 by the refrigerant path 202.
3 is connected to the expansion valve 270 which is a throttle, and the expansion valve 2
70 is connected to a refrigerant evaporator 210 by a refrigerant path 204. The subcooler has, for example, a shell and tube structure. Alternatively, a structure in which one tube having fins attached outside the flow of the regeneration air as a cooling medium is meandering may be used. It is preferable that the refrigerant and the regenerated air have a counterflow.

The space from the condenser 220 to the expansion valve 270 is maintained at a substantially condensing pressure, and the refrigerant liquid is supercooled in the subcooler 280 by the air introduced from the air-conditioned space 101 under the condensing pressure. The subcooled refrigerant is then decompressed by the expansion valve 270 to the evaporating pressure in the evaporator 210.

By cooling the processing air in the evaporator 210, the refrigerant that has gained heat and evaporated to be gasified is guided to the suction side of the refrigerant compressor 260, and the above cycle is repeated.

Next, the operation of the heat pump HP1 in the air conditioning system of FIG. 1 will be further described with reference to the Mollier diagram of FIG. FIG. 3 is a Mollier diagram when the refrigerant HFC134a is used. In this diagram, the horizontal axis is enthalpy and the vertical axis is pressure.

In FIG. 3, a point a corresponds to the refrigerant evaporator 210 of FIG.
This is the state of the refrigerant outlet and the state of the saturated gas. Evaporation pressure
Force is 4.2kg / cm^Two , Temperature is 10 ℃, enthalpy is
It is 148.83 kcal / kg. Compress this gas
The state sucked at 260 and compressed to the condensing pressure is indicated by point b.
Have been. In this state, the pressure is 19.3 kg / cm
^Two , The temperature is about 78 ° C. and is in the state of superheated gas.

This refrigerant gas is cooled in the refrigerant condenser 220 and reaches a point c on the Mollier diagram. Point c is a saturated gas state, the pressure is 19.3 kg / cm ² , and the temperature is 65
° C. Further cooling and condensing under this pressure, the point d
To reach. This point is a state of the saturated liquid, and the pressure and the temperature are the same as those of the point c. And the enthalpy is 122.97kc
al / kg.

The refrigerant liquid in the state at the point d is supplied to the subcooler 280
Is supercooled with the condensing pressure (ignoring the pressure loss due to the flow) to reach the point e. At point e, the pressure is 1
9.3 kg / cm ² , temperature 32 ° C. and enthalpy 110.68 kcal / kg. The air in the air-conditioned space is used as a cooling medium, and this temperature is usually about 27 ° C., so that the temperature at the point e can be about 32 ° C. The condenser 220 may be cooled to a certain degree in a supercooled state, or conversely, a certain amount of gas may be cooled in the subcooler 2.
80 may be mixed.

In FIG. 1, a humidifier (not shown) may be provided in the path 125B to lower the dry-bulb temperature of the air-conditioned space air as a cooling medium. In this way, although the air from the air-conditioned space 101 has a dry bulb temperature lower than that of the outside air, the supercooling temperature of the refrigerant in the subcooler 280 can be further reduced. Further, since the air in the air-conditioned space 101 has a lower wet-bulb temperature than the outside air, the effect of lowering the dry-bulb temperature by humidification is higher than that of the outside air.

The refrigerant liquid in this state is decompressed by the expansion valve 270 and reaches the point j. At point j, the pressure is the evaporation pressure.
2 kg / cm ² , temperature 10 ° C., and enthalpy the same as point e.

The refrigerant liquid itself obtains heat by cooling the processing air, evaporates to the point a, and repeats the above cycle.

As described above, the compressor 260, the refrigerant condenser (regeneration air heater) 220, the subcooler 280,
When the sub-cooler 280 is not provided as the compression heat pump including the throttle 270 and the refrigerant evaporator (processing air cooler) 210, the refrigerant at the point d in the refrigerant condenser 220 is transferred to the refrigerant evaporator 210 via the throttle. To return, the enthalpy difference available in refrigerant evaporator 210 is 148.8
3-12.97 = 25.86 kcal / kg, whereas heat pump H provided with subcooler 280
In the case of P1, 148.83-110.68 = 38.1
5 kcal / kg, and the amount of gas circulating to the compressor for the same cooling load, and consequently the required power, is significantly (about 3
(By 2%). When the air in the air-conditioned space before flowing into the subcooler 280 is humidified, the required power can be further reduced.

As described above, in the subcooler 280, the refrigerant liquid is cooled by the air in the air-conditioned space at a temperature lower than the atmospheric temperature.
The effect of increasing the enthalpy difference available in the refrigerant evaporator 210 is remarkably high. In addition, the outside air is
, The operation is in the ventilation mode, and fresh air can be supplied to the air-conditioned space 101.

[0048]

As described above, according to the present invention, the sixth step of exchanging heat between the refrigerant condensed in the fourth step and the air from the air-conditioned space is provided. Heat exchange with. For example, since the refrigerant is deprived of heat and supercooled, it is possible to increase the enthalpy difference per unit amount of the refrigerant, so that it is possible to provide a dehumidifying method and a dehumidifying apparatus in which COP is significantly improved.

[Brief description of the drawings]

FIG. 1 is a flowchart of a dehumidifying air conditioner according to an embodiment of the present invention.

FIG. 2 is a psychrometric chart for explaining the operation of the dehumidifying air conditioner of FIG.

FIG. 3 is a Mollier diagram of a heat pump used in the dehumidifying air conditioner of FIG.

FIG. 4 is a flowchart of a conventional dehumidifying air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Air-conditioning space 102, 140 Blower 103 Desiccant rotor 104 Heat exchanger 210 Refrigerant evaporator 220 Refrigerant condenser 260 Compressor 270 Restrictor 280 Subcooler HP1 Heat pump

Claims (6)

[Claims] 1. a first step of introducing outside air and desiccantly adsorbing moisture in the outside air; and using the outside air having adsorbed moisture in the first step as a low heat source of the heat pump, A second step of evaporating the working refrigerant to cool the outside air; a third step of supplying the outside air cooled in the second step to the air-conditioned space; and supplying a high heat source of the heat pump to the air from the air-conditioned space. A fourth step of condensing the working refrigerant of the heat pump with the air and heating the air; and regenerating the desiccant adsorbing moisture in the first step with the air heated in the fourth step. And a sixth step of exchanging heat between the refrigerant condensed in the fourth step and air from the air-conditioned space; a dehumidifying method. 2. A heat exchange between the outside air which is adsorbed in the first step and is not cooled in the second step and the air from the air-conditioned space before being heated in the fourth step. The dehumidifying method according to claim 1, further comprising a seventh step of performing the following. 3. The air from the air-conditioned space, which has been used for heat exchange with the refrigerant in the sixth step, is heated as a part of a high heat source of the heat pump by condensing the working refrigerant of the heat pump with the air. The dehumidification method according to claim 1 or 2, further comprising an eighth step. 4. An outside air introduction path; a moisture adsorption device having a desiccant adsorbing moisture in the outside air introduced through the outside air introduction path; and a downstream side of the flow of the outside air with respect to the moisture adsorption device. A cooler provided and configured to cool external air to which moisture has been adsorbed by the desiccant by evaporating a refrigerant; a supply path for introducing the external air cooled by the cooler into an air-conditioned space; and the cooler. And a heater for heating the air from the air-conditioned space by condensing the pressurized refrigerant,
A heater provided upstream of the flow of air from the air-conditioned space with respect to the moisture adsorption device; and a heat exchanger for exchanging heat between the refrigerant condensed by the heater and air from the air-conditioned space. Dehumidifiers; 5. The apparatus according to claim 1, further comprising a second heat exchanger configured to exchange heat between the outside air flowing between the moisture adsorption device and the cooler and air from an air-conditioned space before being heated by the heater. Item 5. A dehumidifier according to Item 4. 6. The dehumidifying apparatus according to claim 5, further comprising a bypass path for introducing air supplied to the heat exchanger in the heat exchanger to the heater by bypassing the second heat exchanger.