JP4857901B2 - Desiccant air conditioning system - Google Patents

Description

  The present invention relates to a desiccant air conditioning system, and more particularly to a desiccant air conditioning system capable of efficiently dehumidifying treated air.

  In the air conditioning system, adjustment of temperature and humidity is an issue, and in particular, a dehumidifying function is important in order to make a high-humidity space a comfortable space. As a dehumidification method, as shown in FIG. 6, using a refrigeration cycle 106 having a compressor 100, an evaporator 102, and a condenser 104, the process air is cooled and dehumidified by the evaporator 102 and reheated by the condenser 104. A cooling dehumidification method for supplying air conditioning space is generally used. This is because the adsorption type as shown in Patent Document 1 requires a large amount of regenerative heat energy for regenerating the desiccant.

  The operation of the cooling and dehumidifying air conditioning system configured as shown in FIG. 6 will be described with reference to the humid air diagram of FIG. In the figure, the horizontal axis represents the dry bulb temperature, the vertical axis represents the absolute humidity, and each oblique line represents an equirelative humidity line. Of the diagonal lines, the solid line indicates the saturation line, that is, the dew point at the absolute humidity. In this example, a case where the hot and humid outdoor air in summer is processed and introduced into the room will be described.

  The process air (state A ') is cooled in the evaporator of the refrigeration cycle and condenses and releases moisture in the process of decreasing temperature along the saturation line (state C' → D '). The treated air is further heated in the condenser of the refrigeration cycle to rise in temperature (state F '), and is led to the conditioned space from the outlet as the treated air with a reduced relative humidity.

  However, in this cooling-type dehumidification method, frost grows in the evaporator when the temperature of the processing air is low and the dew point is below freezing point. For this reason, defrosting work is required after an operation for a predetermined time, and continuous operation is impossible. Further, when the temperature of the processing air is low, as shown by the broken line in the Mollier diagram of FIG. 3, the evaporating temperature of the refrigerant is lowered and the refrigeration effect is reduced, so that a sufficient dehumidifying ability cannot be obtained. there were.

Japanese Patent Application Laid-Open No. 08-210664

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an air conditioning system having a function of dehumidifying continuously and efficiently even when the temperature of the processing air is low.

In order to achieve the above object, the invention according to claim 1 is a honeycomb-shaped desiccant rotor carrying a desiccant that adsorbs moisture in the air and is capable of desorbing moisture in the air. Is divided into an adsorption zone that adsorbs moisture and a desorption zone that desorbs moisture, and a desiccant rotor in which the air flowing through the adsorption zone and the air flowing through the desorption zone form a counterflow; compressor, evaporator and condensation A refrigeration cycle comprising a refrigeration unit; the processing air introduced into the system is configured to flow in the order of a desiccant rotor desorption zone, a refrigeration cycle evaporator, the desiccant rotor adsorption zone, and a refrigeration cycle condenser. It is a characteristic desiccant air conditioning system.
In the first aspect of the present invention, a higher dehumidifying action can be obtained by combining the refrigeration cycle with a moisture adsorption step by a desiccant rotor.

According to a second aspect of the present invention, in the desiccant air conditioning system according to the first aspect, a sensible heat exchanger for exchanging heat between the processed air after passing through the condenser and the air before entering the desorption zone of the desiccant is provided. It is characterized by that.
In the invention of claim 2, since heat recovery is performed by the sensible heat exchanger, the adsorption capacity of the desiccant when the indoor relative humidity is high increases, the dehumidification amount increases, and the compression power per dehumidification amount decreases. To save energy.

The invention according to claim 3 is the desiccant air conditioning system according to claim 2, wherein the exchange heat quantity of the sensible heat exchanger is variable.
In invention of Claim 3, it can respond to dehumidification air-conditioning load of various sensible heat ratios by adjusting the exchange heat amount of a sensible heat exchanger according to required dehumidification load.

  According to the first to third aspects of the present invention, it is possible to provide an air conditioning system having a function of dehumidifying continuously and efficiently even when the temperature of the processing air is low.

Embodiments of the present invention will be described below with reference to the drawings.
The desiccant air conditioning system shown in FIG. 1 is disposed across a frame 14 that forms an introduction flow path 10 and a discharge flow path 12 for processing air, and between the introduction flow path 10 and the discharge flow path 12. A desiccant rotor 16 that circulates alternately between the two flow paths, a refrigeration cycle 24 composed of a compressor 18, an evaporator 20, and a condenser 22 and a blower 26 are provided, and further, a clear air is introduced between the introduced air and the derived air. And a sensible heat exchanger 28 for performing heat exchange.

  These devices are arranged as follows. That is, the processing air introduced from the inlet 32 to the introduction passage 10 passage passes through the high temperature zone 28 a of the sensible heat exchanger 28 and the desorption zone 16 a of the desiccant rotor 16 and reaches the evaporator 20 of the refrigeration cycle 24. Water is condensed and released. The processing air further flows into the outlet channel 12 and is exhausted from the outlet 34 through the adsorption zone 16b of the desiccant rotor 16, the condenser 22 of the refrigeration cycle 24, and the low temperature zone 28b of the sensible heat exchanger 28.

  The desiccant rotor 16 is a honeycomb-like rotor that supports a desiccant that adsorbs moisture in the air and can desorb moisture in the air, and is disposed across both the introduction channel 10 and the outlet channel 12. The portion on the introduction flow channel 10 side becomes a desorption zone 16a for desorbing moisture, and the portion on the discharge flow channel 12 side becomes an adsorption zone for adsorbing moisture to dehumidify. The air flowing through the adsorption zone 16b and the air flowing through the desorption zone 16a are almost in counterflow.

  Further, in this embodiment, the sensible heat exchanger 28 is also a honeycomb-shaped rotor whose heat exchange medium is disposed across both the introduction flow path 10 and the discharge flow path 12, and heat exchange is performed by the rotation thereof. Is to be done. Therefore, the amount of exchange heat can be adjusted by the rotational speed of the heat exchange medium.

  The operation of the thus configured desiccant air conditioning system will be described with reference to the wet air diagram of FIG. In the figure, the horizontal axis represents the dry bulb temperature, the vertical axis represents the absolute humidity, and each oblique line represents an equirelative humidity line. Of the diagonal lines, the solid line indicates the saturation line, that is, the dew point at the absolute humidity. In this example, a case where the hot and humid outdoor air in summer is processed and introduced into the room will be described.

  The processing air (state A) passes through the low temperature zone 28a of the sensible heat exchanger 28, and heat is exchanged with the sensible heat exchange rotor 32 to increase the temperature (state B). The process air whose temperature has increased passes through the desorption zone 16a of the desiccant rotor 16, absorbs moisture along the isoenthalpy line BC, desorbs the desiccant, increases the humidity, and decreases the temperature (state C). This treated air is further cooled in the evaporator 20 of the refrigeration cycle 24, and condenses and releases moisture in the process of decreasing the temperature along the saturation line (state D). The treated air passes through the adsorption zone 16b of the desiccant rotor 16, is adsorbed with moisture along the isoenthalpy line DE, decreases in humidity, and increases in temperature (state E). The processing air is further heated in the condenser 22 of the refrigeration cycle 24 to rise in temperature (state F), and further passes through the high temperature zone 28b of the sensible heat exchanger 28 to exchange heat with the sensible heat exchange rotor 32. Then, the air to be treated is cooled (state G) and treated as air having a reduced relative humidity, and is led out to the conditioned space through the outlet 34.

  Thus, in this embodiment, even when the relative humidity of the processing air indicated by the state A is high for heat recovery by the sensible heat exchanger 28, the relative air at the desorption process inlet indicated by the state B is relatively high. Since the humidity decreases (drys), the moisture desorption effect in the desorption zone of the desiccant rotor increases, and the moisture adsorption dehumidification effect in the adsorption zone increases accordingly, and the dehumidification amount increases.

  Further, when it is desired to obtain dehumidified air having the same absolute humidity in the conventional cooling and dehumidifying air conditioning system, as shown in the humid air diagram of FIG. 3, when the coefficient of performance (COP) of the refrigeration cycle is 3, In the present invention, the heat ratio CD: EF≈3: 4 applied from the refrigeration cycle and the heat ratio CD ′: D′ F ′ of the conventional cooling and dehumidifying air conditioning system are substantially the same (≈3: 4) or the exhaust heat is increased. Therefore, the processing air temperature after cooling and dehumidification indicated by state D ′ is lowered and the processing air temperature after reheating indicated by state E ′ is also increased in the conventional cooling and dehumidifying air conditioning system. To do. Therefore, as shown in the Mollier diagram of FIG. 4, in the present invention, the evaporation pressure of the evaporator that exchanges heat with the air shown in the state D is higher than that in the conventional cooling and dehumidifying air conditioning system, and in the state F, Since the condensation pressure of the condenser that exchanges heat with the processing air to be shown is reduced, the compression power is reduced and energy is saved.

In the above embodiment, when the sensible heat exchanger 28 is not used, the moisture adsorption action by the desiccant is reduced, so that the absolute humidity of the final process air is also increased. The necessity of the sensible heat exchanger 28 may be determined according to the situation in which the desiccant air conditioning system is used.
Further, indoor humidity (relative humidity, dew point temperature or absolute humidity) may be detected, and when the humidity is high, the sensible heat rotor may be rotated.
Further, the exchange heat quantity may be adjusted by changing the number of revolutions of the sensible heat rotor in accordance with the measured value of the humidity in the room. By changing the number of revolutions, the sensible heat ratio (SHF) shown in FIG. 2 changes and the position of point E changes. Can do.

  FIG. 5 shows another embodiment of the present invention, which is a desiccant air conditioning system for humidifying a room in winter. In this embodiment, the indoor air is dehumidified to have an absolute humidity lower than that of the outside air and exhausted to the outside, and the outside air having an absolute humidity higher than that of the exhaust is taken in and heated and humidified. A second processing path 42 is provided. The first processing path 40 has basically the same configuration as the desiccant air conditioning system of the previous embodiment, but an auxiliary condenser 44 is provided in the refrigeration cycle 24, and this is connected to the second processing path 42. It is installed and used for warming the outside air.

  In the second processing path 42, the auxiliary condenser 44 is installed on the downstream side of the blower 46, and a vaporizing humidifier 48 is installed on the downstream side of the second processing path 42, so that freshly heated and humidified air is supplied into the room. . In this embodiment, since the moisture dehumidified in the first treatment path 40 is used as the water source of the humidifier 48, it is not necessary to supply water. The water purification and sterilization device 50 is installed on the upstream side of the humidifier 48 so that the purified water is used for humidification.

  The second processing air path 42 does not necessarily have to be opened outdoors, and may be opened indoors. In this case, the outside air corresponding to the amount of air discharged from the first processing air path 40 flows from the gaps of the windows or the natural ventilation openings, and the mixed air of the outside air and the room air is combined with the second processing air. However, it does not impair the humidifying action in the room, and can be used as a countermeasure when only one opening to the outdoors is allowed for the convenience of construction.

It is a figure which shows the structure of the desiccant air conditioning system of 1st Embodiment of this invention. It is a humid air line figure for demonstrating operation | movement of the desiccant air conditioning system of 1st Embodiment. In order to compare the case where the desiccant air-conditioning system of 1st Embodiment is used, and the case where the conventional system is used, it is a humid air line figure explaining the state of the air which heat-exchanges with a refrigerating cycle. It is a Mollier diagram explaining a refrigerating cycle in order to compare the case where the desiccant air-conditioning system of a 1st embodiment is used, and the case where a conventional system is used. It is a figure which shows the structure of the desiccant air-conditioning system of 2nd Embodiment of this invention. It is a figure which shows the structure of the conventional air conditioning system. It is a humid air line figure for demonstrating operation | movement of the conventional air conditioning system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Introduction flow path 12 Outlet flow path 14 Frame 16 Desiccant rotor 16a Desorption zone 16b Adsorption zone 18 Compressor 20 Evaporator 22 Condenser 24 Refrigerating cycle 26 Blower 28 Sensible heat exchanger 28a High temperature zone 28b Low temperature zone 30 Inlet port 32 Outlet port 40 1st processing path 42 2nd processing path 44 Auxiliary condenser 46 Blower 48 Humidifier 50 Water purification purification sterilizer

Claims (3)

A honeycomb-shaped desiccant rotor carrying a desiccant capable of adsorbing moisture in the air and capable of desorbing moisture in the air, wherein the desiccant rotor is divided into an adsorption zone for adsorbing moisture and a desorption zone for desorbing moisture. A desiccant rotor in which the air flowing through the adsorption zone and the air flowing through the desorption zone form a substantially counterflow; and a refrigeration cycle comprising a compressor, an evaporator, and a condenser;
A desiccant air-conditioning system configured to flow processing air introduced into the system in the order of a desiccant rotor desorption zone, a refrigeration cycle evaporator, the desiccant rotor adsorption zone, and a refrigeration cycle condenser. The desiccant air conditioning system according to claim 1 , further comprising a sensible heat exchanger for exchanging heat between the processed air after passing through the condenser and the air before flowing into the desorption zone of the desiccant rotor .
The desiccant air conditioning system according to claim 2, wherein the amount of heat exchanged by the sensible heat exchanger is variable.

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