JP2003114067A - Adsorption heat pump - Google Patents

Abstract

(57) To provide an adsorption heat pump or a dehumidifying air conditioner capable of adsorbing and desorbing an adsorbate in a low relative vapor pressure region. SOLUTION: An adsorbent, an adsorption / desorption portion having an adsorbent for adsorbing and desorbing the adsorbate, an evaporation portion for evaporating the adsorbate connected to the adsorption / desorption portion, and an adsorption / desorption portion connected to the adsorption / desorption portion In an adsorption heat pump with a condensing part that condenses adsorbate,
The adsorbent is A) Framework density is 10.0T / 1,000Å ³
An adsorption heat pump characterized in that it is a zeolite having 16.0 T / 1,000 to ³ or less, B) a pore diameter of 3 to 10 and C) a differential adsorption heat of 40 kJ / mol to 65 kJ / mol.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adsorption heat pump using a specific adsorbent, a vehicle air conditioner and a dehumidifying air conditioner using the adsorbent.

[0002]

2. Description of the Related Art In an adsorption heat pump or a dehumidifying air conditioner, in order to regenerate an adsorbent that adsorbs adsorbate, for example, water, the adsorbent is heated to desorb the adsorbate, and the dried adsorbent is replaced with the adsorbate. Cool to the temperature used for adsorption and use again for adsorption of adsorbate. Absorption heat pumps have already been put into practical use, which utilize exhaust heat and warm heat at a relatively high temperature (120 ° C. or higher) as a heat source for regenerating an adsorbent. However, in general, the heat obtained from cooling water of the cogeneration equipment, fuel cells, automobile engines, solar heat, etc. is a relatively low temperature of 100 ° C. or lower, so it cannot be used as a drive heat source for absorption heat pumps currently in practical use. Therefore, effective utilization of low temperature exhaust heat of 100 ° C. or lower, and further 60 ° C. to 80 ° C. has been demanded.

Further, although the operation principle of the adsorption heat pump is the same, the adsorption characteristics required for the adsorbent material largely differ depending on the available heat source temperature. For example, the exhaust heat temperature of a gas engine cogeneration or polymer electrolyte fuel cell used as a heat source on the high temperature side is 60 ° C to 80 ° C, and the temperature of cooling water of an automobile engine is 85 ° C to 90 ° C. The heat source temperature on the cooling side also differs depending on the installation location of the device. For example, in the case of a car, it is the temperature obtained by a radiator, and in the case of buildings and houses, it is the temperature of water cooling towers and river water. That is, the operating temperature range of the adsorption heat pump is 25 ° C. to 35 ° C. on the low temperature side when installed in a building or the like, 60 ° C. to 80 ° C. on the high temperature side, and 30 ° C. to 40 ° C. on the low temperature side when installed in an automobile or the like. The high temperature side is about 85 ° C to 90 ° C. As described above, in order to effectively use the exhaust heat, a device that can be driven even if the temperature difference between the low temperature side heat source and the high temperature side heat source is small is desired.

In order for the device to operate sufficiently even at a relatively high temperature around the adsorbent, it is necessary to adsorb the adsorbate at a low relative vapor pressure, and the adsorbent to be used must be small in amount to miniaturize the device. In order to do so, it is necessary that the adsorption / desorption amount of the adsorbent is large. The desorption temperature must be low in order to use a low temperature heat source for desorption of the adsorbate (regeneration of the adsorbent). That is, as an adsorbent used in an adsorption heat pump or a dehumidifying air conditioner, (1) adsorbs an adsorbate at a low relative vapor pressure (it can be adsorbed at a high temperature), (2) has a large adsorption / desorption amount, and (3) has a high relative vapor. An adsorbent that can be desorbed by pressure (desorbable at low temperature) is desired.

Silica gel and zeolite with a low silica-alumina ratio have generally been used as adsorbents for adsorption heat pumps. However, the adsorbents that have been conventionally used in adsorption heat pumps have insufficient adsorbing / desorbing ability to use a relatively low temperature heat source as a driving source for the adsorption heat pump. For example, considering a 13X water vapor adsorption isotherm as a typical example of zeolite for an adsorption heat pump, the water vapor adsorption amount of zeolite is rapidly adsorbed at a relative vapor pressure of 0.05 or less, and in a relative vapor pressure range higher than 0.05. It does not change. When regenerating the adsorbent, the relative humidity of the surrounding gas is reduced to desorb and remove the water once adsorbed, but the relative vapor pressure must be lowered to desorb the water adsorbed on the zeolite 13X. Therefore, it is said that a heat source of 150 ° C to 200 ° C is required.

Further, a mesoporous molecular sieve (FSM-10 etc.) synthesized by using a micelle structure of a surfactant as an adsorbent for a heat pump as a template (JP-A-9-17).
No. 8292), and a porous aluminum phosphate-based molecular sieve commonly referred to as AlPO ₄ for desiccant (JP-A-11-197439).
The mesoporous molecular sieve (FSM-10) has an adsorption amount difference of 0.2 in the range of relative vapor pressures of 0.20 and 0.35.
As large as 5 g / g, it is a promising material (Japanese Patent Laid-Open No. 9-17
8292: Graph 4 in FIG. 14; FSM-10). However, the adsorption amount is small in the range of relatively low relative vapor pressure,
Even in the range of the relative vapor pressure where the adsorption amount change is large, the adsorption amount difference is small, and the performance of the adsorption heat pump is insufficient.
Further, it has been pointed out that the structure collapses and the function as an adsorbent is deteriorated when it is repeatedly used, and durability is an issue.

[0007]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of providing an efficient adsorption heat pump or dehumidifying air conditioner using an adsorbent capable of adsorbing and desorbing an adsorbate in a low relative vapor pressure region. .

[0008]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that an adsorption heat pump using a zeolite having a framework density, a pore diameter and a heat of adsorption within a specific range as an adsorbent. Further, it has been found that a dehumidifying air conditioner and a vehicle air conditioner using the adsorbent achieve the object of the present invention.

That is, the gist of the present invention is to provide an adsorbate, an adsorption / desorption part provided with an adsorbent for adsorbing / desorbing the adsorbate, and an evaporation / condensing part for evaporating / condensing the adsorbate connected to the adsorption / desorption part. In the adsorption heat pump equipped with, the adsorbent has A) a framework density of 10.0 T / 1,000Å ³
Above 16.0 T / 1,000 Å ³ or less, B) Pore size 3 Å or more and 10 Å or less, and C) Zeolite having a differential heat of adsorption of 40 kJ / mol or more and 65 kJ / mol or less. Exist. Another feature is a dehumidifying air conditioner having a path for treated air in which water is adsorbed by an adsorbent and a path for regenerated air that is heated by a heating source and then desorbs and regenerates water in the adsorbent after adsorbing the water. The adsorbent has a framework density of 10.0 T / 1,000 Å ³ or more 1)
6.0T / 1,000Å ³ or less, B) Pore size is 3Å or more and 10Å or less, and C) Heat of adsorption is 40 kJ / mol or more, 65 kJ / m
It exists in a dehumidifying air-conditioning device characterized by being a zeolite having an ol or less.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. The operating vapor pressure range of the adsorption heat pump is determined by the desorption-side relative vapor pressure φ1 and the adsorption-side relative vapor pressure φ2 obtained by the following equation, and the operable vapor pressure range is between φ1 and φ2.

Desorption side relative vapor pressure φ1 = equilibrium vapor pressure (Tl
ow1) / equilibrium vapor pressure (Thigh) Adsorption side relative vapor pressure φ2 = equilibrium vapor pressure (Tcool) / equilibrium vapor pressure (Tlow2) where the high temperature heat source temperature Thigh is to desorb the adsorbate from the adsorbent to regenerate the adsorbent. The temperature of the heating medium to be heated when
The low-temperature heat source temperature Tlow1 is the temperature of the adsorbate in the condenser, the low-temperature heat source temperature Tlow2 is the temperature of the heat medium that cools the adsorbent after regeneration when adsorbing it, and the cold heat generation temperature Tcool is the temperature of the adsorbate in the evaporator. The temperature, that is, the temperature of the generated cold heat,
means. The equilibrium vapor pressure can be calculated from the temperature using the equilibrium vapor pressure curve of the adsorbate.

The operating vapor pressure range when the adsorbate is water will be exemplified below. High temperature heat source temperature 80 ℃, low temperature heat source temperature 3
When the temperature is 0 ° C, the operating vapor pressure range is φ1 to φ2 = 0.09 to
It is 0.29. Similarly, when the high temperature heat source temperature is 60 ° C,
Operating relative water vapor pressure range is φ1-φ2 = 0.21-0.2
It is 9. Further, in the case of driving the adsorption heat pump by utilizing the exhaust heat of the automobile engine, Japanese Patent Application Laid-Open No. 2000-
It is described in detail in No. 140625. Estimating based on this report, the high temperature heat source temperature is about 90 ° C and the low temperature heat source temperature is 3
It is 0 ° C. In this case, the operating relative water vapor pressure range is φ1-
φ2 = 0.06 to 0.29.

From the above, when the adsorption heat pump is driven by utilizing the exhaust heat of the gas engine cogeneration, the polymer electrolyte fuel cell or the automobile engine, the operating relative water vapor pressure range is φ1 to φ2 = 0.05 to 0. 30 and, if further limited, φ1 and φ2 = 0.06 to 0.29. That is, when the relative water vapor pressure is lowered by heating and the adsorbent is regenerated, the relative water vapor pressure is 0.05,
Desorption must be completed within a range of preferably 0.06 or more. On the other hand, in terms of adsorption, the relative vapor pressure is 0.3.
A sufficient adsorption amount must be obtained in the range of 0, preferably 0.29 or less. That is, a material having a large change in adsorption amount within this operating humidity range is preferable. Therefore, usually, a material whose adsorption amount largely changes in a relative vapor pressure range of 0.05 to 0.30, preferably in a range of 0.06 to 0.29 is preferable.

For example, by an adsorption heat pump, 5.0 k
Suppose that a cooling capacity of W (= 18,000 kJ) is obtained. Here, 5.0 kW is a wooden room 16 facing south
It is the air-conditioning capacity of an air conditioner that is used for an air conditioner of a tatami mat or a general automobile. The latent heat of vaporization of water is about 250
0 kJ / kg, 10 cycles of adsorption / desorption switching
Assuming minutes (6 times / hour), if the adsorption amount is 0.18 g / g, 6.7 kg of the adsorbent is required. Required amount of adsorbent Xkg = 18000kJ / (2500kJ × 0.18
kg / kg × 6 times / hr) = 6.7 kg. Similarly, if the adsorption amount is 0.15 g / g, 8 kg is required. When the switching cycle reaches 6 minutes (10 times / hour), it is 0.1
When it is 8 g / g, it becomes 4.0 kg, and when it is 0.15 g / g, it becomes 4.8 kg. The larger the adsorption amount, the better, but
For example, the smaller the weight and volume of the adsorbent is, the better for mounting the adsorption heat pump on an automobile in a limited size. In order to satisfy these conflicting requirements, it is necessary to increase the adsorption amount, and it is considered that an adsorbent having an adsorption amount of 0.18 g / g or more, more preferably 0.20 g / g or more is preferable.

Here, the adsorption heat pump and the dehumidifying air conditioner use the ability of the adsorbent to adsorb and desorb the adsorbate as a drive source. In the dehumidifying air conditioner, the moisture in the treated air is the adsorbate. In the adsorption heat pump, water, ethanol, acetone, etc. can be used as the adsorbate which is the adsorbate, but among them, water is the most preferable from the viewpoint of safety, price and latent heat of vaporization. The adsorbate is adsorbed on the adsorbent as vapor, and the adsorbent is preferably a material having a large change in adsorption amount in a narrow relative vapor pressure range. If the change in adsorption amount is large in a narrow relative vapor pressure range, the amount of adsorbent required to obtain the same adsorption amount under the same conditions is reduced, and the adsorption heat pump is driven even if the temperature difference between the cooling heat source and the heating heat source is small. Because you can.

The adsorbent used in the adsorption heat pump of the present invention (hereinafter sometimes referred to as the adsorbent of the present invention) will be described below. In the present invention, zeolite is used as the adsorbent, and its framework density is 10.0.
T / 1,000 Å ³ or more 16.0T / 1,000Å ³ or less, preferably 10.0T / 1,000Å ³ to 15.
It is 0T / 1,000Å ³ or less. Here, the framework density means the number of elements constituting the skeleton other than oxygen per 1,000 Å ³ of zeolite, and this value is determined by the structure of zeolite.

That is, framework density correlates with pore volume, and generally zeolites with smaller framework densities have larger pore capacities and therefore higher adsorption capacities. Framework density is 16.0T
If it is larger than / 1,000 Å ^{3, the} pore volume that can be adsorbed becomes small and the adsorbed amount becomes insufficient, so it is not suitable as an adsorbent for an adsorption heat pump and a dehumidifying air conditioner. On the other hand, if the framework density is less than 10.0 T / 1,000 Å ^{3, the} pore volume that can be adsorbed increases, but the density of the substance decreases, which is not preferable.

The IZA Atlas Of Zeolite Structure
Types (1996, ELSEVIER) describes the relationship between structure and framework density and pore size. As the structure of zeolite satisfying the above framework density, AFG, MER, LIO, LOS,
PHI, BOG, ERI, OFF, PAU, EAB, A
FT, LEV, LTN, AEI, AFR, AFX, GI
S, KFI, CHA, GME, THO, MEI, VF
I, AFS, LTA, FAU, RHO, DFO, EM
T, AFY, * BEA, etc., preferably AEI, G
IS, KFI, CHA, GME, VFI, AFS, LT
A, FAU, RHO, EMT, AFY, * BEA are mentioned.

The structure of zeolite is International
Zeolite having a CHA structure, an AEI structure or an ERI structure in the zeolite structure defined by Zeolite Association (IZA) is preferable. The structure of zeolite is powder XR
D (XRD pattern was measured by powder X-ray diffraction, Co
reflection of Simulated XRD
Powder Patterns For Zeol
X described in ITE (1996, ELSEVIER)
Determined by comparison with the RD pattern.

Not limited to the above examples, if the framework density is within this region, it is considered that the framework can be preferably used as the adsorbent in the present invention. The pore size of the adsorbent of the present invention is 3Å or more and 10Å or less. Above all, 3Å or more,
It is preferably 8 Å or less, more preferably 3 Å or more and 7.5 Å or less. If the pore size is larger than 10Å, adsorption will not occur at the target relative humidity, which is unsuitable, and if the pore size is smaller than 3Å, water molecules that are adsorbates are less likely to diffuse into the adsorbent, which is unsuitable. In particular, this tendency is remarkable in the zeolite containing aluminum and phosphorus in the skeleton structure and further in the aluminophosphate called ALPO which exhibits hydrophobicity.

Further, the adsorbent of the present invention has a differential heat of adsorption of 40.
It is not less than kJ / mol and not more than 65 kJ / mol. That is,
It is also an important property that the adsorption heat pump and the adsorbent of the dehumidifying air conditioner that need to be desorbed with a heat source of 100 ° C. or less are easily desorbed. Ease of desorption is inversely proportional to adsorption force. Therefore, it is desirable that the heat of adsorption, which is an index indicating the degree of adsorption, be close to the latent heat of condensation of water, and it does not decrease any further and is 40 kJ / mol or more. According to our study, if the heat of differential adsorption is larger than 65 kJ / mol, it is difficult to desorb with a heat source of 100 ° C. or lower. Therefore, a zeolite having a differential heat of adsorption of not less than the latent heat of condensation of water and not more than 65 kJ / mol is preferable. The differential heat of adsorption is calculated from the Clausius-Clapeyron equation by measuring adsorption isotherms at different temperatures. This time, the method of measuring the adsorption isotherm at two temperatures of 25 ° C. and 40 ° C. and calculating the differential heat of adsorption from the results was adopted.

The adsorbent of the present invention needs to satisfy the above three conditions at the same time, and a material that does not satisfy even one of the conditions is not suitable for the purpose of the present invention. The zeolite that is the adsorbent of the present invention preferably contains aluminum and phosphorus in its skeletal structure. The zeolite here may be a natural zeolite or an artificial zeolite.
Includes aluminophosphates defined by the ternational Zeolite Association (IZA). Commonly known as ALPO
And aluminophosphates are particularly preferred.

Specific examples of the particularly preferable adsorbent used in the present invention include ALPO-34, ALPO-18, and ALPO-.
No. 17, and the former two are particularly preferable. ALPO-3
4 is CHA type (framework density = 14.6T / 1,
000Å ³ , zeolite with a pore size of 3.8 × 3.8Å),
ALPO-18 is AEI type (framework density = 1
4.8T / 1,000Å ³ , Pore size 3.8 × 3.8Å)
Zeolite, ALPO-17, is ERI type (framework density = 15.7T / 1000Å ³ pore size 3.6 x
It is a zeolite of 5.1Å).

Further, in the adsorbent used in the present invention, when the relative vapor pressure changes by 0.15, the adsorption amount of water changes by 0.18 g /
It is an adsorbent having a relative vapor pressure region of not less than 0.2 g and preferably not less than 0.20 g / g, and preferably in the range of not less than 0.05 and not more than 0.20 relative vapor pressure.
It is an adsorbent having a relative vapor pressure region in which a change in the amount of water adsorbed when it changes 15 is 0.18 g / g or more, preferably 0.20 g / g or more. The water vapor adsorption isotherm of the present invention is an adsorption isotherm at an adsorption temperature of 25 ° C, and changes in relative vapor pressure and water adsorption amount can be obtained from the water vapor adsorption isotherm.

One of the features of the present invention is that an adsorbent having the above characteristics is used. This adsorbent can be used in the adsorbing part of various conventionally known air conditioners having an adsorbing / desorbing part for adsorbates, which is represented by an adsorbent heat pump or a dehumidifying air conditioner. The dehumidifying air conditioner is synonymous with a so-called desiccant air conditioner. Further, since a large change in the adsorption amount can be obtained by changing the relative vapor pressure in a narrow range, it is suitable for an adsorption heat pump having a limited adsorbent filling amount, such as a vehicle air conditioner.

The operation of the adsorption heat pump or dehumidifying air conditioner of the present invention using the above-mentioned adsorbent will be specifically described below with reference to the adsorption heat pump having the equipment structure shown in FIG. 1. The adsorption heat pump or dehumidifying air conditioner of the present invention will be described below. The device is not limited to this. A conceptual diagram of an example of the adsorption heat pump of the present invention is shown in FIG. The adsorption heat pump shown in FIG. 1 includes an adsorbent capable of adsorbing and desorbing an adsorbate,
Adsorption towers 1 and 2 which are filled with an adsorbent and which transfer heat generated by adsorption / desorption of an adsorbate to a heat medium, and an evaporator 4 for extracting cold heat obtained by evaporation of the adsorbate to the outside.
And a condenser 5 that releases the heat generated by the condensation of the adsorbate to the outside. When operating the adsorption heat pump, determine the operating conditions from the adsorption isotherm at ambient temperature so that the adsorption / desorption amount required for operation can be obtained.
Usually, it is determined so that the maximum adsorption / desorption amount can be obtained when the device is operated.

As shown in FIG. 4, the adsorption towers 1 and 2 filled with the adsorbent are connected to each other by an adsorbate pipe 30, and the adsorbate pipe 30 is provided with control valves 31 to 34. Here, the adsorbate exists in the adsorbate pipe as a vapor of the adsorbate or a mixture of the liquid and vapor of the adsorbate. An evaporator 4 and a condenser 5 are connected to the adsorbate pipe 30. The adsorption towers 1 and 2 are connected in parallel between the evaporator 4 and the condenser 5, and between the condenser 5 and the evaporator 4 to return the adsorbate condensed in the condenser to the evaporator 4. Return piping 3
To provide. Reference numeral 41 is an inlet of cold water that serves as cooling output from the evaporator 4, and reference numeral 51 is an inlet of cooling water to the condenser 5. Reference numerals 42 and 52 are cold water and cooling water outlets, respectively. In addition, the cold water pipes 41 and 42 have an indoor unit 300 for exchanging heat with the indoor space (air-conditioned space).
And a pump 301 for circulating cold water is connected.

A heat medium pipe 11 is connected to the adsorption tower 1 and a heat medium pipe 21 is connected to the adsorption tower 2, and the changeover valves 115 and 116 and 215 and 216 are connected to the heat medium pipes 11 and 21, respectively. Is provided. Further, the heat medium pipes 11 and 21 flow the heat medium as a heating source or a cooling source for heating or cooling the adsorbents in the adsorption towers 1 and 2, respectively. The heat medium is not particularly limited as long as it can effectively heat and cool the adsorbent in the adsorption tower.

Hot water is supplied to the switching valves 115, 116, 2
By opening and closing 15, 15 and 216, it is introduced through the inlet 113 and / or 213, passes through the adsorption towers 1 and / or 2, and is led out through the outlet 114 and / or 214. The cooling water is also introduced from the inlets 111 and / or 211 by opening / closing the similar switching valves 115, 116, 215, and 216, passes through the adsorbers 1 and / or 2, and the outlet 1
12 and / or 212. Further, to the heat medium pipes 11 and / or 21, an outdoor unit (not shown) arranged to be able to exchange heat with the outside air, a heat source for generating hot water, and a pump for circulating the heat medium are connected. The heat source is not particularly limited, and examples thereof include an automobile engine, a cogeneration device such as a gas engine and a gas turbine, and a fuel cell, and when used for an automobile, an automobile engine and an automobile fuel cell are examples of preferable heat sources. As.

A method of operating the adsorption heat pump will be described with reference to FIG. In the first step, the control valves 31 and 34 are closed, the control valves 32 and 33 are opened, and the regeneration step is performed in the adsorption tower 1 and the adsorption step is performed in the adsorption tower 2. Further, the switching valves 115, 116, 215, and 216 are operated to cause hot water to flow through the heat medium pipe 11 and cool water through the heat medium pipe 21.

When the adsorption tower 2 is cooled, the cooling water which has been cooled by exchanging heat with outside air, river water, etc. by a heat exchanger such as a cooling tower is introduced through the heat medium pipe 21, and usually 30-40.
It is cooled to about ℃. Further, by opening the control valve 32, the water in the evaporator 4 evaporates to become water vapor and the adsorption tower 2
Flows into the and is adsorbed by the adsorbent. Water vapor transfer occurs due to the difference between the saturated vapor pressure at the evaporation temperature and the adsorption equilibrium pressure corresponding to the adsorbent temperature (generally 20 to 50 ° C, preferably 20 to 45 ° C, more preferably 30 to 40 ° C). In the evaporator 4, cold heat corresponding to the heat of vaporization of evaporation, that is, cooling output is obtained. From the relationship between the temperature of the cooling water and the temperature of the generated cold water, the adsorption-side relative vapor pressure φ2 (where φ2 is the equilibrium vapor pressure of the adsorbate at the temperature of the generated cooling water is divided by the equilibrium vapor pressure of the adsorbate at the temperature of the cooling water). To obtain)
However, it is preferable to operate so that φ2 becomes larger than the relative vapor pressure at which the adsorbent specified in the present invention maximally adsorbs water vapor. This is because when φ2 is smaller than the relative vapor pressure at which the adsorbent specified in the present invention adsorbs water vapor to the maximum, the adsorbing ability of the adsorbent cannot be effectively utilized and the operation efficiency deteriorates. φ2 can be appropriately set depending on the environmental temperature, etc., but the adsorption amount at φ2 is usually 0.20.
Or more, preferably 0.29 or more, more preferably 0.3
The adsorption heat pump is operated under the temperature condition of 0 or more.

The adsorption tower 1 in the regeneration step usually has a capacity of 40 to 10
0 ° C, preferably 50 to 98 ° C, more preferably 60 to
It is heated by hot water of 95 ° C to reach the equilibrium vapor pressure corresponding to the above temperature range, and the condensation temperature of the condenser 5 is 30 to 40 ° C.
(This is equal to the temperature of the cooling water cooling the condenser)
It is condensed at the saturated vapor pressure at. Water vapor moves from the adsorption tower 1 to the condenser 5 and is condensed into water. Water return pipe 3
Is returned to the evaporator 4. Desorption side relative vapor pressure φ1 (where φ1 is the equilibrium vapor pressure of the adsorbate at the temperature of the cooling water, the heat used for regeneration) from the relationship between the temperature of the cooling water and the temperature of the heat medium (hot water) used for regeneration. (Determined by dividing by the equilibrium vapor pressure of the adsorbate at the medium (warm water) temperature) is determined, and φ1 is operated so that the adsorbent specified in the present invention becomes smaller than the relative vapor pressure at which the adsorbent rapidly adsorbs water vapor. It is preferable. If φ1 is larger than the relative vapor pressure at which the adsorbent specified by the present invention rapidly adsorbs water vapor, the excellent adsorption amount of the adsorbent specified by the present invention cannot be effectively utilized. φ1 can be appropriately set depending on the environmental temperature, etc., but the adsorption amount at φ1 is usually 0.06 or less,
The adsorption heat pump is preferably operated under a temperature condition of 0.05 or less. The difference between the adsorbed amount of the adsorbate at φ1 and the adsorbed amount of the adsorbate at φ2 is usually 0.18 g.
/ G or more, preferably 0.20 g / g or more, more preferably 0.25 g / g or more. The above is the first step.

In the next second step, the adsorption tower 1 uses the adsorption step,
The control valves 31 to 3 are arranged so that the adsorption tower 2 is in the regeneration process.
4 and switching valves 115, 116, 215, and 2
By switching 16 the cold heat, that is, the cooling output can be obtained from the evaporator 4 in the same manner. The adsorption heat pump is continuously operated by sequentially switching the above first and second steps.

Although the operation method in the case where two adsorption towers are installed is described here, either adsorbent can adsorb the adsorbate by appropriately desorbing the adsorbate adsorbed by the adsorbent. Any number of adsorption towers may be installed as long as the state can be maintained.

[0035]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples unless it exceeds the gist. Synthesis Example 1 Synthesis of ALPO-34 ALPO-34 was prepared from Microporous and Mesoporous Materia
It was synthesized according to ls 30, (1999), 145-153.

4.6 g of boehmite (containing 25% water) was added to a solution of 7.7 g of 85% phosphoric acid and 20 g of water, and the mixture was stirred for 1 hour. A solution of 7.25 g of morpholine and 38.4 g of water was added thereto, a 47% hydrogen fluoride aqueous solution was further added, and the mixture was stirred for 3 hours. This was placed in a stainless steel autoclave lined with Teflon (registered trademark) and heated at 200 ° C. for 10 days. The product was filtered, washed with water, dried, and calcined in an air stream at 560 ° C. for 6 hours to obtain AlPO-34.
When the XRD of this zeolite was measured, it had a CHA structure. Synthesis Example 2 Synthesis of ALPO-18 ALPO-18 was synthesized according to JP-B-1-57041. 9.52 g (25% water content) of boehmite was added to a solution of 16.1 g of 85% phosphoric acid and 30 g of water, and the mixture was stirred for 1 hour. To this, 39.38 g of a 35% tetraethylammonium hydroxide aqueous solution and 2.27 g of 37% hydrochloric acid were added, and the mixture was stirred for 3 hours. This was placed in a Teflon-lined stainless steel autoclave and heated at 150 ° C. for 14 days. The product was filtered, washed with water, dried, and calcined at 560 ° C. for 6 hours in an air stream to obtain ALPO-18. When the XRD of this zeolite was measured, it had an AEI structure. Examples 1-2 ALPO-34 of Synthesis Example 1 (Example 1), A of Synthesis Example 2
About LPO-18 (Example 2), 25
The water vapor adsorption temperature curve at ° C was determined.

Adsorption isotherm measuring device: Bellsorb 18 (Nippon Bell Co., Ltd.) Air high temperature tank temperature: 50 ° C., adsorption temperature: 25 ° C., initial introduction pressure: 3.0 torr, introduction pressure set point: 0, saturated vapor pressure : 23.76 mmHg, equilibration time: 500 seconds.

The adsorption isotherms of water vapor of ALPO-34 at 25 ° C. and 40 ° C. are shown in FIG. From FIG. 2, in the adsorption isotherm at an adsorption temperature of 25 ° C., a relative vapor pressure of 0.0
It can be seen that water vapor is rapidly adsorbed in the vicinity of 6, and the amount of change in adsorption amount in the relative vapor pressure range of 0.05 to 0.20 is 0.24 g / g. The framework density of ALPO-34 is 14.6T / 1,000Å ³ , and the pore size is 3.8.
× 3.8Å. Further, the differential heat of adsorption is about 60 kJ / mol when calculated from the adsorption isotherms at 25 ° C. and 40 ° C. shown in FIG. 2 using the Clausius-Clapeyron equation.

The adsorption temperature of ALPO-18 at 25 ° C.
The adsorption isotherm of water vapor is shown in FIG. Adsorption isotherm From Figure 3
Absorbs water vapor rapidly at a relative vapor pressure of around 0.08
The amount of change in adsorption amount in the relative vapor pressure range of 0.05 to 0.20
It can be seen that is 0.30 g / g. In addition, ALPO-
No. 18 has a framework density of 14.8T / 1,000Å
³, And the pore size is 3.8 × 3.8Å. As shown in FIG.
From the adsorption isotherms at 25 ° C and 40 ° C
Approximately 60 kJ / m when the differential heat of adsorption is calculated using the Peyron equation
It becomes ol.

Reference Example 1 FIG. 4 shows an AFI type porous aluminum phosphate-based molecular sieve (framework density = 17.3T / 1,
000Å ³ , Pore size 7.3 x 7.3Å) Adsorption isotherm (Colloid Pol) of ALPO-5 which is a zeolite
ym Sci 277, p83-88 (1999),
Fig. 1 (quoted from the adsorption temperature of 30 ° C.) is shown. ALPO-5 has a relative vapor pressure of 0.25 to 0.40
The adsorption amount rises sharply in the range of
It is possible to adsorb and desorb in the range of 0.3, but the change in adsorption amount in the range of relative vapor pressure of 0.15 to 0.30 is 0.
It is 14 g / g.

Reference Example 2 FIG. 5 shows FAU type zeolite 13X (framework density = 12.7T / 1,000Å ³ , pore size 7.4 × 7.4).
Shows the adsorption isotherm at 25 ° C of × 7.4 Å) (Source: Heat storage / heat increasing technology (heat storage / heat increasing technology editorial committee edition), IPC Corporation, P342). 13X, which is a FAU structure, has a small framework density of 12.7T / 1,000Å ³ and a pore size of 7.4 × 7.4 × 7.4Å, which is smaller than 10Å and is suitable, but as shown in FIG. Adsorption occurs in an extremely low relative vapor pressure region, and the difference in the adsorption amount in the relative vapor pressure region used in the present invention is small, which is not practical. Relative vapor pressure 0.
In Fig. 5, 05 is 1.19 Torr, relative vapor pressure 0.20 is 4.75 toor, and relative vapor pressure 0.30 is 7.13 Torr.
In the range of 0.20, 1.15-4.75 Torr in Fig. 5, the difference in adsorption amount is about
It is 0.06 g / g. This is because the 13X differential heat of adsorption is greater than 65 kJ / mol over the entire range, so that adsorption occurs in an extremely low relative vapor pressure region. Figure 6 shows the heat of differential adsorption of Geolite 13X.
(Source: heat storage / heat increase technology (edited by the heat storage / heat increase technology), IPC Corporation, P342).

[0042]

The adsorbent used in the present invention has a larger amount of adsorption in the same relative vapor pressure range as compared with conventional silica gel or zeolite. The effect can be generated. Furthermore, the adsorption heat pump or dehumidifying air conditioner using an adsorbent that exhibits a large change in adsorption / desorption amount in a relatively low relative vapor pressure range of the present invention has a large difference in the amount of adsorbed water due to adsorption / desorption of the adsorbent. Since it is possible to regenerate (desorb) the adsorbent at a temperature, it is possible to efficiently drive the adsorption heat pump or the dehumidifying air conditioner by using a heat source having a temperature lower than that in the past. That is, according to the adsorbent of the present invention, it is possible to provide an adsorption heat pump and a dehumidifying air conditioner that are driven by a heat source of a relatively low temperature of 100 ° C. or lower.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an adsorption heat pump.

FIG. 2 is a water vapor adsorption isotherm of ALPO-34 at 25 ° C. and 40 ° C.

FIG. 3 shows water vapor adsorption isotherms of ALPO-18 at 25 ° C. and 40 ° C.

FIG. 4 is a water vapor adsorption isotherm of ALPO-5.

FIG. 5 is a water vapor adsorption isotherm of zeolite 13X.

FIG. 6 is a differential adsorption heat diagram of zeolite 13X.

[Explanation of symbols]

1 adsorption tower 2 adsorption tower 3 Adsorbate piping 4 evaporator 5 condenser 11 Heat medium piping 111 Cooling water inlet 112 cooling water outlet 113 hot water inlet 114 hot water outlet 115 switching valve 116 switching valve 21 Heat medium piping 211 Cooling water inlet 212 Cooling water outlet 213 Hot water inlet 214 Hot water outlet 215 switching valve 216 switching valve 30 Adsorbate piping 31 Control valve 32 control valve 33 Control valve 34 Control valve 300 indoor units 301 pump 41 Cold water piping (inlet) 42 Cold water piping (outlet) 51 Cooling water piping (inlet) 52 Cooling water piping (outlet)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B01J 20/34 B01J 20/34 G B60H 1/32 621 B60H 1/32 621J 3/00 3/00 A ( 72) Inventor Takahiko Takewaki 1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa Mitsubishi Kagaku Co., Ltd. (72) Inventor Hideaki Tamiya 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Chemical Co., Ltd. (72) Inventor Masanori Yamazaki Chuo 8-3-1, Ami-cho, Inashiki-gun, Ibaraki Mitsubishi Chemical Co., Ltd. (72) Inventor Watanabe Exhibition 1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa Mitsubishi Chemical Co., Ltd. F-term (reference) 3L093 NN04 PP14 PP15 4D012 BA02 CB16 CD04 CG01 CG05 CG10 CK01 4D052 AA08 CD01 DA08 GB14 HA03 4G066 AA61B BA23 BA36 BA38 CA43 DA03 GA04

Claims (11)

[Claims] 1. An adsorbate, an adsorbent / desorber having an adsorbent for adsorbing and desorbing the adsorbate, an evaporator for evaporating the adsorbate connected to the adsorbent / desorber, and an adsorbent / desorber connected to the adsorbent / desorber. In an adsorption heat pump equipped with a condensing unit that condenses the adsorbate,
The adsorbent has A) framework density of 10.0 T / 1,000Å ³
Above 16.0 T / 1,000 Å ³ or less, B) A zeolite having an pore diameter of 3 Å or more and 10 Å or less, and C) a differential heat of adsorption of 40 kJ / mol or more and 65 kJ / mol or less. 2. The adsorbent has a water vapor adsorption amount change of 0.18 g / g or more when the relative vapor pressure changes by 0.15 within a range of relative vapor pressure of 0.05 or more and 0.30 or less. The adsorption heat pump according to claim 1, which is an adsorbent having a relative vapor pressure range. 3. The adsorption heat pump according to claim 1, wherein the adsorbent has an adsorption amount of 0.05 g / g or less at a relative vapor pressure of 0.05. 4. The adsorption heat pump according to claim 1, wherein the zeolite is a zeolite containing aluminum and phosphorus in its skeletal structure. 5. The adsorption heat pump according to claim 1, wherein the zeolite is aluminophosphate. 6. An air conditioning system for a vehicle, wherein the adsorption heat pump according to claim 1 is used for air conditioning of a vehicle interior. 7. A path for treated air in which water is adsorbed by the adsorbent, and a path for regenerated air that is heated by a heating source and then desorbs and regenerates the water in the adsorbent after adsorbing the water. In the dehumidifying air conditioner, the adsorbent has A) a framework density of 10.0 T / 1,000Å ³
Above 16.0 T / 1,000 Å ³ or less, B) Zeolite having a pore size of 3 Å or more and 10 Å or less, and C) differential adsorption heat of 40 kJ / mol or more and 65 kJ / mol or less. 8. The adsorbent has a change in the adsorption amount of water of 0.18 g / g or more when the relative vapor pressure changes by 0.15 within a range of the relative vapor pressure of 0.05 or more and 0.30 or less. The dehumidifying air conditioner according to claim 7, which is an adsorbent having a relative vapor pressure range. 9. The dehumidifying air conditioner according to claim 7, wherein the adsorbent has an adsorption amount of 0.05 g / g or less at a relative vapor pressure of 0.05. 10. The dehumidifying air-conditioning device according to claim 7, wherein the zeolite is a zeolite containing aluminum and phosphorus in its skeletal structure. 11. The dehumidifying air conditioner according to claim 7, wherein the zeolite is aluminophosphate.