JP4249437B2 - Adsorption heat pump, adsorption heat pump operation method, and vehicle air conditioner using adsorption heat pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water vapor adsorbent for adsorption heat pump containing zeolite, an adsorption heat pump using the water vapor adsorbent, a vehicle air conditioner using the heat pump, and the like.
[0002]
[Prior art]
Adsorbents are used in adsorption heat pumps and dehumidifying air conditioners, but in order to regenerate the adsorbate, for example, adsorbent that has adsorbed water, the adsorbent is heated to desorb the adsorbate, and the dried adsorbent is removed from the adsorbent. It is cooled to the temperature used for adsorption and used again for adsorbate adsorption.
[0003]
In order to desorb the adsorbate from the adsorbent, an adsorption heat pump using exhaust heat or heat at a relatively high temperature (120 ° C. or higher) has already been put into practical use. However, since the heat obtained by cooling water or solar heat from cogeneration equipment, fuel cells, automobile engines, etc. is relatively low at 100 ° C or less, it cannot be used as a driving heat source for adsorption heat pumps that are 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.
[0004]
Although the operation principle of the adsorption heat pump is the same, the adsorption characteristics required for the adsorbent differ greatly depending on the available heat source temperature. For example, the exhaust heat temperature of a gas engine cogeneration or a polymer electrolyte fuel cell to be used as a heat source on the high temperature side is 60 ° C. to 80 ° C., and the temperature of cooling water for an automobile engine is 85 ° C. to 90 ° C. .
[0005]
And the temperature of the heat source for cooling the dried adsorbent also varies depending on the installation location of the apparatus. For example, in the case of an automobile, the temperature is obtained by a radiator, and in a building or a house, the temperature is such as a water cooling tower or 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, 30 ° C to 40 ° C on the low temperature side when installed on an automobile, etc. The high temperature side is about 85 ° C to 90 ° C. In order to effectively utilize such low-temperature exhaust heat, an apparatus 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.
[0006]
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 to reduce the size of the device by using a small amount of adsorbent. Needs a large amount of adsorption / desorption of the adsorbent. In order to use a low-temperature heat source for adsorbate desorption (regeneration of adsorbent), the desorption temperature needs to be low. That is, as an adsorbent used in an adsorption heat pump or a dehumidifying air conditioner, (1) an adsorbate adsorbs at a low relative vapor pressure, (2) a large amount of adsorption / desorption, and (3) an adsorbent that adsorbs an adsorbate at a high relative vapor pressure. Is desired.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide an adsorbent that adsorbs and desorbs water vapor in a low relative vapor pressure region, and an efficient adsorption heat pump using the adsorbent.
[0008]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors have found a water vapor adsorbent suitable for an apparatus using adsorption / desorption of adsorbate such as an adsorption heat pump as a drive source of the apparatus.
That is, the gist of the present invention is an adsorbent, an adsorption / desorption portion having an adsorbent for adsorbing / 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. An operation method of an adsorption heat pump comprising a condensing part for condensing adsorbate, wherein the adsorbent is a water vapor adsorbent containing zeolite, and the zeolite contains aluminum, phosphorus and silicon in the skeleton structure, And the integrated intensity area of the signal intensity of -108 ppm to -123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm, The method of operating an adsorption heat pump, wherein the adsorbate is desorbed from the heat medium and the temperature of the heating medium heated when the adsorbent is regenerated is 100 ° C. or less Exist.
Other aspects of the present invention include an adsorbate, an adsorption / desorption portion having an adsorbent for adsorbing / desorbing the adsorbate, an evaporation portion for evaporating the adsorbate connected to the adsorption / desorption portion, and a connection to the adsorption / desorption portion. An operation method of an adsorption heat pump comprising a condensing unit for condensing the adsorbate formed, wherein the adsorbent is a water vapor adsorbent containing zeolite, and the zeolite contains aluminum, phosphorus and silicon in the skeleton structure. And the integrated intensity area of the signal intensity of -108 ppm to -123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm, The adsorbate is desorbed from the material to regenerate the adsorbent, and the temperature of the heating medium to be heated is 60 to 95 ° C., and the temperature of the condensing part is 30 to 40 ° C. This is the operation method of the adsorption heat pump.
Still another gist of the present invention is that an adsorbate, 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 the adsorption / desorption portion a suction pump having a condenser portion for performing condensation of concatenated adsorbate, the temperature of the heat medium for heating the pre-Symbol adsorbent when reproducing the adsorbent to desorb the adsorbate 100 ° C. or less and then, the adsorbent is a water vapor adsorption material comprising zeolite comprises said zeolite is aluminum skeletal structure, phosphorus and silicon, and, -108ppm~-123ppm in ²⁹ Si-MAS-NMR spectra of the zeolite The integrated intensity area of the signal intensity is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm, and aluminum contained in the framework structure of the zeolite, The abundance ratio of phosphorus and silicon atoms is represented by the following formulas (1), (2) and (3)
0.001 ≦ x ≦ 0.3 (1)
(In the formula, x represents the molar ratio of silicon to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ y ≦ 0.6 (2)
(Wherein y represents the molar ratio of aluminum to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ z ≦ 0.6 (3)
(Wherein z represents the molar ratio of phosphorus to the total of aluminum, phosphorus and silicon in the skeleton structure)
When the relative vapor pressure in the water vapor adsorption isotherm in the range of relative vapor pressure of 0.05 to 0.30 is changed by 0.15, the change in the adsorption amount of water is 0.18 g / g. those having more relative vapor pressure range, lies in the adsorption heat pump, characterized in that.
Still another subject matter of the present invention lies in a vehicle air conditioner characterized in that the adsorption heat pump is used for air conditioning in a vehicle compartment.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
First, the operation principle of the adsorption heat pump of the present invention will be described.
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 from the high temperature heat source temperature High, the low temperature heat source temperature Tlow1, the low temperature heat source temperature Tlow2, and the cold heat generation temperature Tcool.
[0010]
φ1 and φ2 are the following formulas (a) and (b)
Desorption side relative vapor pressure φ1 = equilibrium vapor pressure (Tlow1) / equilibrium vapor pressure (High) (a)
Adsorption side relative vapor pressure φ2 = equilibrium vapor pressure (Tcool) / equilibrium vapor pressure (Tlow2) (b)
The relative vapor pressure range that can be operated is between φ1 and φ2.
[0011]
Here, the high temperature heat source temperature High is the temperature of the heat medium heated when desorbing the adsorbate from the adsorbent to regenerate the adsorbent, the low temperature heat source temperature Tlow1 is the temperature of the adsorbate in the condensing part, and the low temperature heat source temperature Tlow2. Means the temperature of the heat medium to be cooled when the adsorbent after regeneration is used for adsorption, and the cold generation temperature Tcool means the temperature of the adsorbate in the evaporation section, that is, the temperature of the generated cold. The equilibrium vapor pressure can be determined from the temperature using the equilibrium vapor pressure curve of the adsorbate.
[0012]
Hereinafter, the operating vapor pressure range when the adsorbate is water will be exemplified. When the high temperature heat source temperature High is 80 ° C., the low temperature heat source temperature Tlow 1 is 30 ° C., and the cold heat generation temperature Tcool is 10 ° C., the operating vapor pressure range is φ1 to φ2 = 0.09 to 0.29. Similarly, when the high-temperature heat source temperature is 60 ° C., the operation relative water vapor pressure range is φ1 to φ2 = 0.21 to 0.29. Further, the case of driving the adsorption heat pump using the exhaust heat of the automobile engine is described in detail in Japanese Patent Application Laid-Open No. 2000-140625. Based on this report, the high temperature heat source temperature is about 90 ° C. and the low temperature heat source temperature is 30 ° C. In this case, the operation relative water vapor pressure range is φ1 to φ2 = 0.06 to 0.29.
[0013]
From the above, when the adsorption heat pump is driven using the exhaust heat of the gas engine cogeneration, the polymer electrolyte fuel cell or the automobile engine, the operation relative water vapor pressure range is φ1 to φ2 = 0.05 to 0.30. If limited, it is considered that φ1 to φ2 = 0.06 to 0.29. That is, when the adsorbent is regenerated by lowering the relative water vapor pressure by heating, desorption must be completed when the relative water vapor pressure is in the range of 0.05, preferably 0.06 or more. On the other hand, in terms of adsorption, a sufficient adsorption amount must be obtained within a relative vapor pressure of 0.30, preferably 0.29 or less. That is, a material having a large change in adsorption amount within this operating humidity range is preferable. Therefore, the lower limit of the relative vapor pressure is 0.05, preferably 0.06, the upper limit is 0.30, preferably 0.29, that is, the relative vapor pressure range is selected from a combination of these lower and upper limits. Preferably, a material whose adsorption amount greatly changes in the range of 0.05 to 0.30, more preferably 0.06 to 0.29 is appropriate.
[0014]
For example, it is assumed that a cooling capacity of 3.0 kW (= 10,800 kJ / hr) is obtained by an adsorption heat pump. Here, 3.0 kW is the cooling capacity of an air conditioner used for a general automobile air conditioner. It is considered that the capacity of the adsorption heat pump is desirably at least 15 liters or less based on engine room surveys of various vehicles.
[0015]
Next, the adsorbent weight that can be filled in a volume of 15 liters or less is determined.
The parts to be mounted in the engine room include an adsorption tower body, an evaporator, a condenser, and control valves. It is necessary to make the assembly in which these are integrally formed into a capacity of 15 liters or less. In our study, it is considered that the size of the evaporator, condenser and valves can be formed with about 4.5 liters. Therefore, the capacity of the adsorption tower body is approximately 10.5 liters or less. Since the adsorbent packing ratio and the adsorbent bulk density in the adsorption tower are usually about 30% and about 0.6 kg / liter, respectively, the adsorbent weight (W) that can be packed is 10.5 × 30% × 0.6. = 1.89kg.
[0016]
Next, characteristics required for the adsorbent will be described.
The cooling capacity R in the adsorption heat pump is expressed by the following formula A.
R = (W · ΔQ · η _C · ΔH / τ) · η _h (Formula A)
Here, W is the weight of the adsorbent packed in one adsorption tower (one side), ΔQ is the equilibrium adsorption amount amplitude in the conditions of adsorption and desorption, and the adsorption amount difference (Q2-Q1), and η _C is the equilibrium adsorption. Adsorption amplitude efficiency indicating the ratio of the actual adsorption amplitude within the switching time with respect to the amplitude ΔQ, ΔH is the latent heat of vaporization of water, τ is the switching time between the adsorption process and the desorption process, η _h is the hot water in the adsorbent and heat exchanger The heat mass efficiency which considered the heat mass loss by changing the temperature between temperature and cooling water temperature is shown.
[0017]
As described above, R is 3 kW, and W is 1.89 kg / 2 = 0.95 kg. From our past studies, τ is appropriately about 60 seconds, and ΔH, η _C , and η _h are about 2500 kJ / kg, 0.6, and 0.85, respectively (Equation A). When ΔQ is obtained,
ΔQ = R / W / η _C / ΔH ・ τ / η _h = 3.0 / 0.95 / 0.6 / 2500 ・ 60 / 0.85 = 0.149kg / kg
It becomes. That is, as an adsorbent used for the adsorption heat pump for automobiles, ΔQ is preferably 0.15 g / g or more, 0.18 g / g or more, and more preferably 0.20 g / g or more.
[0018]
As described above, the description has been made on the assumption that it is applied to an automobile, but it goes without saying that it can be sufficiently applied to other uses such as stationary use as long as the above characteristics are satisfied.
Adsorption heat pumps use the ability of adsorbents to adsorb and desorb adsorbates as a drive source. In the adsorption heat pump, water, ethanol, acetone, or the like can be used as the adsorbate, but water is most preferable because of its 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. When 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 it can.
[0019]
The water vapor adsorbing material of the present invention is a water vapor adsorbing material containing zeolite, which has one feature. Water vapor adsorbents are used in dehumidifiers, desiccant air conditioners, humidity control building materials, etc. that directly adsorb water vapor in the atmosphere, and are used as adsorbents in environments where only water vapor exists in a vacuum, such as adsorption heat pumps. .
[0020]
The zeolite contained in the water vapor adsorbent of the present invention (hereinafter sometimes referred to as “the zeolite of the present invention”) will be described in detail below.
The zeolite of the present invention contains aluminum, phosphorus and silicon in the framework structure.
The integrated intensity area of the signal intensity of −108 ppm to −123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite of the present invention is preferably 10% or less with respect to the integrated intensity area of the signal intensity of −70 ppm to −123 ppm, preferably Is 9.5% or less, more preferably 9% or less of zeolite. If the intensity area ratio is too large, the adsorption / desorption characteristics in the low relative vapor pressure region are inferior.
[0021]
Further, the integrated intensity area of the signal intensity of -70 ppm to -92 ppm in the ²⁹ Si-MAS-NMR spectrum is 25% or more with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm, preferably 50%. That's it.
The ²⁹ Si-MAS-NMR spectrum in the present invention was obtained by measuring a sample in which tetramethylsilane was used as a standard substance and a sample was stored in a water desiccator at room temperature for a whole day and saturated with water, under the following conditions. is there.
Device: Chemical CMX-400
Probe: 7.5 mm MAS probe resonance frequency: 79.445 MHz
Pulse width: 5.0 microseconds Pulse series: Single pulse waiting time: 60 seconds Rotation speed: 4000 rps
The ²⁹ Si-MAS-NMR spectrum of zeolite gives information on the bonding state of Si in the zeolite, and the Si bonding state can be known from the position and distribution of the peak.
[0022]
The zeolite of the present invention contains aluminum, phosphorus and silicon, and the silicon atom in the zeolite is present in units of SiO ₂ . Here, in the spectrum of ²⁹ Si-MAS-NMR, the peak in the vicinity of −90 ppm is that in which a silicon atom is bonded to an atom other than four silicon atoms via an oxygen atom. On the other hand, the peak in the vicinity of −110 ppm is one in which a silicon atom is bonded to four silicon atoms via oxygen atoms. That is, a zeolite having a high peak intensity around −110 ppm means that silicon atoms gather together and the dispersibility of silicon atoms in the zeolite is low.
[0023]
It is considered that the dispersibility of Si affects the adsorption characteristics of the zeolite, and as will be described later, zeolite having a high dispersibility of silicon atoms exhibits performance particularly suitable for an adsorbent of an adsorption heat pump.
In the zeolite of the present invention, the abundance ratio of aluminum, phosphorus and silicon atoms is represented by the following formulas (1), (2) and (3).
0.001 ≦ x ≦ 0.3 (1)
(Wherein x represents the molar ratio of silicon to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ y ≦ 0.6 (2)
(Wherein y represents the molar ratio of aluminum to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ z ≦ 0.6 (3)
(Wherein z represents the molar ratio of phosphorus to the total of aluminum, phosphorus and silicon in the skeleton structure)
Those satisfying the above are preferable.
Among the abundance ratios of the atoms in the zeolite, the abundance ratio (x) of silicon in the formula (1) is preferably 0.25 or less, and more preferably 0.2 or less.
[0024]
Further, as described above, a silicon atom having high dispersibility is considered preferable in terms of the adsorptive performance of the present invention, and in order to obtain such dispersibility, the silicon abundance ratio (x) is , 0.09 or less tends to be advantageous, 0.085 or less is more preferable, and 0.08 or less is particularly preferable. Further, the silicon presence ratio (x) is preferably 0.003 or more, more preferably 0.005 or more, and particularly preferably 0.01 or more.
[0025]
Moreover, as long as it is in the range of silicon, aluminum, and phosphorus having the above composition, other elements may be included in the skeleton. Examples of other elements include lithium, magnesium, titanium, zirconium, vanadium, chromium, manganese, iron, cobalt, nickel, palladium, copper, zinc, gallium, germanium, arsenic, tin, calcium, and boron. The zeolite includes those having a cation species exchangeable with other cations. In this case, the cations include protons, alkaline elements such as Li, Na, and K, alkaline earth elements such as Mg and Ca, Examples include rare earth elements such as La and Ce, and transition metal elements such as Fe, Co, and Ni. Protons, alkali elements, and alkaline earth elements are preferable.
[0026]
The above atomic ratio can be determined by elemental analysis. Elemental analysis values are obtained by ICP analysis after dissolving a sample with a hydrochloric acid aqueous solution.
The zeolite of the present invention may be a natural zeolite or an artificial zeolite. For example, an artificial zeolite includes aluminosilicates, aluminophosphates, and the like according to International Zeolite Association (IZA) regulations.
[0027]
The structure of the zeolite of the present invention is represented by a code defined by International Zeolite Association (IZA), and is usually AEI, AFR, AFS, AFT, AFT, AFX, AHT, CHA, DFO, ERI, FAU, GIS, LEV, LTA, VFI. AEI, GIS, CHA, VFI, AFS, LTA, FAU, and AFY are preferable, and CHA is most preferable.
[0028]
The structure of the zeolite is determined by measuring the XRD pattern by powder XRD (powder X-ray diffraction) and comparing it with the XRD pattern described in Collection Of Simulated XRD Powder Patterns For Zeolites (1996, ELSEVIER).
Also, the relationship between the structure and the framework density is described in IZA's Atlas Of Zeolite Structure Types (1996, ELSEVIER), and the framework density can be known from the structure.
[0029]
The framework density of the zeolite of the present invention is usually from 10.0 T / 1000 A ^{3 to} 16.0 T / 1000 A ³ , preferably from 10.0 T / 1000 A ^{3 to} 15.0 T / 1000 A ³ .
As for the zeolite of the present invention, when the relative vapor pressure changes by 0.15 in the normal vapor pressure isotherm of 0.05 to 0.30 in the water vapor adsorption isotherm, the water adsorption amount changes by 0.18 g / g or more. Zeolite is preferable, and zeolite changing by 0.20 g / g or more is more preferable. Further, a zeolite in which the amount of water adsorbed changes by 0.18 g / g or more within a relative vapor pressure of 0.05 to 0.20 is more preferable, and a zeolite in which 0.20 g / g or more changes is most preferable. In the water vapor adsorption isotherm, the adsorption amount at a relative vapor pressure of 0.05 is usually 0.15 g / g or less, preferably 0.12 g / g or less, more preferably 0.10 g / g or less, particularly 0.07 g. / G or less is preferable, and 0.05 g / g or less is most preferable.
[0030]
In addition, the measurement of the water vapor adsorption isotherm of the water vapor adsorbent in the present invention is performed under the following conditions.
Adsorption isotherm measuring device: Bersorb 18 (Nippon Bell Co., Ltd.)
Air hot bath temperature: 50 ° C
Adsorption temperature: 25 ° C
Initial introduction pressure: 3.0 torr
Introduced pressure setting points: 0
Saturated vapor pressure: 23.76 mmHg
Equilibrium time: 500 seconds Pretreatment: 200 ° C., evacuation for 5 hours The production method of the zeolite of the present invention is not particularly limited as long as it has the above-mentioned properties, but for example, Japanese Patent Publication No. 4-37007 and Japanese Patent Publication No. 5-21844 It can be produced by the following method according to the methods described in Japanese Patent Publication No. 5-51533, US Pat. No. 4,440,871 and the like.
[0031]
First, an aqueous gel is prepared by mixing an aluminum source, a silica source, a phosphoric acid source and a template.
As the aluminum source, pseudoboehmite, aluminum isopropoxide, aluminum hydroxide, alumina sol, sodium aluminate and the like are used.
As the silica source, fumed silica, silica sol, colloidal silica, water glass, ethyl silicate, methyl silicate and the like are used.
[0032]
Phosphoric acid is used as the phosphoric acid source. Aluminum phosphate can also be used.
As templates, quaternary ammonium salts such as tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, morpholine, di-n-propylamine, tri-n-propylamine, tri-n-isopropylamine, triethylamine, Triethanolamine, piperidine, cyclohexylamine, 2-methylpyridine, N, N-dimethylbenzylamine, N, N-diethylethanolamine, dicyclohexylamine, N, N-dimethylethanolamine, choline, N, N′-dimethylpiperazine 1,4-diazabicyclo (2,2,2) octane, N-methyldiethanolamine, N-methylethanolamine, N-methylpiperidine, 3-methylpiperidine, N-methylcyclohexyl Ruamine, 3-methylpyridine, 4-methylpyridine, quinuclidine, N, N'-dimethyl-1,4-diazabicyclo- (2,2,2) octane ion, di-n-butylamine, neopentylamine, gin- Primary amine, secondary amine such as pentylamine, isopropylamine, t-butylamine, ethylenediamine, pyrrolidine, 2-imidazolidone, di-isopropyl-ethylamine, dimethylcyclohexylamine, N-methyl-n-butylamine, hexamethyleneimine, Tertiary amines and polyamines are used. These may be used as a mixture. Of these, morpholine, triethylamine, cyclohexylamine, isopropylamine, di-isopropyl-ethylamine, N-methyl-n-butylamine, and tetraethylammonium hydroxide are preferable, and industrially cheaper morpholine, triethylamine, and cyclohexylamine are more preferable. . These may be used alone or in combination of two or more.
[0033]
The order of mixing the aluminum source, the silica source, the phosphoric acid source and the template varies depending on the conditions. Usually, however, the phosphoric acid source and the aluminum source are first mixed, and then the silica source and the template are mixed. The composition of the aqueous gel is expressed by the molar ratio of the oxide, and is generally 0.02 <SiO ₂ / P ₂ O ₅ <20, 0.02 <SiO ₂ / Al ₂ O ₃ <20, preferably 0 .04 <SiO ₂ / P ₂ O ₅ <10, 0.04 <SiO ₂ / Al ₂ O ₃ <10. The pH of the aqueous gel is 5 to 10, preferably 6 to 9. In addition, in order for the silicon abundance ratio (x) to be 0.09 or less as one method for obtaining a silicon atom having good dispersibility, the composition of the aqueous gel is expressed by the molar ratio of the oxide, 0.02 <SiO ₂ / Al ₂ O ₃ <0.5 is preferable, more preferably 0.02 <SiO ₂ / Al ₂ O ₃ <0.4, and particularly preferably 0.02 <SiO ₂ / Al ₂ O. ₃ <0.35. The ratio of P ₂ O ₅ / Al ₂ O ₃ is 0.6 or more and 1.3 or less, preferably 0.7 or more and 1.2 or less, more preferably 0.8 or more and 1.1 or less. The proportion of water is usually 3 or more, preferably 5 or more, more preferably 10 or more, and usually 200 or less, preferably 150 or less, more preferably 120 or less, in molar ratio with respect to Al ₂ O ₃ . is there.
[0034]
In addition, you may coexist a component other than the above suitably in aqueous gel. Examples of such components include hydrophilic organic solvents such as hydroxides and salts of alkali metals and alkaline earth metals, and alcohols.
The prepared aqueous gel is put into a pressure vessel, and hydrothermal synthesis is performed by maintaining a predetermined temperature under stirring or standing under self-generated pressure or gas pressurization that does not inhibit crystallization.
[0035]
The conditions for hydrothermal synthesis are usually 100 ° C to 300 ° C, preferably 120 ° C to 250 ° C. The reaction time is usually 5 hours to 30 days, preferably 10 hours to 15 days.
After hydrothermal synthesis, the product is separated, washed with water, dried, and the organic matter contained is removed by a method such as calcination to obtain zeolite.
[0036]
As a particularly preferred zeolite of the present invention, for example, silicoaluminophosphate having a CHA structure can be mentioned. From the standpoint of adsorption characteristics, the pore diameter of zeolite is preferably 3 to 10 mm.
Since the zeolite contained in the water vapor adsorbent of the present invention exhibits a large change in adsorption amount with a small relative vapor pressure, zeolite alone can be used as an excellent water vapor adsorbent. When used as an adsorbent for an adsorption heat pump, the zeolite can be processed into a water vapor adsorbent having characteristics such as predetermined strength, particle diameter, and shape.
[0037]
When processing zeolite for use as a water vapor adsorbent, it is necessary to take care not to lower the adsorption performance of the zeolite, but in general, molding is performed using an inorganic binder such as alumina or silica.
Further, in order to give the water vapor adsorbing material the desired water vapor adsorbing properties, silica gel, mesoporous silica, alumina, activated carbon, clay and the like may be included in the water vapor adsorbing material in addition to the zeolite of the present invention. However, in order to obtain good adsorption characteristics at a low relative vapor pressure, the ratio of the zeolite to the water vapor adsorbent of the present invention is usually 60% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more, From the standpoint of adsorption characteristics, it is most preferable to use only zeolite as a water vapor adsorbent.
[0038]
When the water vapor adsorbing material of the present invention is used for water vapor adsorption, a large amount of water vapor is adsorbed in a low relative vapor pressure region, water vapor can be adsorbed efficiently, and it can be used in an adsorption / desorption portion of an adsorption heat pump.
The water vapor adsorbing material of the present invention has an adsorption amount that changes more at a low relative vapor pressure compared to conventional silica gel and zeolite. And an evaporating part for evaporating the adsorbate connected to the adsorption / desorption part and a condensing part for condensing the adsorbate connected to the adsorption / desorption part.
[0039]
In addition, since a large change in the adsorption amount can be obtained with a narrow range of relative vapor pressure changes, among adsorption heat pumps, an adsorption heat pump that requires a smaller apparatus and a limited amount of adsorbent, such as a vehicle air conditioner, is used. It can be suitably used.
The operating conditions of the adsorption heat pump using the water vapor adsorbent of the present invention may be selected as appropriate so that the performance of the adsorption heat pump is manifested as desired, but the equilibrium vapor pressure of the cooling water temperature is used to desorb the adsorbate from the adsorbent. The desorption side relative vapor pressure φ1 determined by dividing by the equilibrium vapor pressure of the heat source temperature to be used is 0.05 or more, and the equilibrium vapor pressure of the generated cold temperature is divided by the equilibrium vapor pressure of the cooling water temperature. It is also possible to select severe conditions such that the determined adsorption-side relative vapor pressure φ2 is 0.30 or less.
[0040]
Hereinafter, although the effect | action of the adsorption heat pump of this invention is demonstrated concretely, the adsorption heat pump of this invention is not limited by this.
An example of a conceptual diagram of the adsorption heat pump of the present invention is shown in FIG. The adsorption heat pump shown in FIG. 10 includes an adsorbent capable of adsorbing and desorbing adsorbate, and adsorption towers 1 and 2 which are adsorbing and desorbing portions filled with the adsorbent and transmitting heat generated by adsorption and desorption of the adsorbate to a heat medium. The evaporator 4 takes out the cold heat obtained by the evaporation of the adsorbate and the condenser 5 discharges the hot heat obtained by the condensation of the adsorbate to the outside. When operating the adsorption heat pump, the operation conditions are obtained from the adsorption isotherm at the ambient temperature so that the adsorption / desorption amount necessary for the operation can be obtained, and the maximum adsorption / desorption amount is usually obtained when the apparatus is operated. To be determined.
[0041]
As shown in FIG. 10, 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 as an adsorbate vapor or a mixture of adsorbate liquid and vapor in the adsorbate pipe.
The evaporator 4 and the 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, the adsorbate condensed in the condenser is returned to the evaporator 4. The return pipe 3 is provided. Reference numeral 41 denotes an inlet of cold water that serves as a cooling output from the evaporator 4, and reference numeral 51 denotes an inlet of cooling water to the condenser 5. Reference numerals 42 and 52 denote outlets of cold water and cooling water, respectively. The cold water pipes 41 and 42 are connected to an indoor unit 300 for exchanging heat with the indoor space (air-conditioned space) and a pump 301 for circulating cold water.
[0042]
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. The heat medium pipes 11 and 21 are provided with switching valves 115 and 116, and 215 and 216, respectively. is there. The heat medium pipes 11 and 21 flow a heat medium serving 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 the adsorbent in the adsorption tower can be effectively heated and cooled.
[0043]
The hot water is introduced from the inlets 113 and / or 213 by opening and closing the switching valves 115, 116, 215, and 216, passes through the adsorption towers 1 and / or 2, and is led out from the outlets 114 and / or 214. The cooling water is also introduced from the inlets 111 and / or 211 by opening / closing similar switching valves 115, 116, 215, and 216, passes through the respective adsorbers 1 and / or 2, and is led out from the outlets 112 and / or 212. The Moreover, although not shown in figure, the outdoor unit arrange | positioned so that heat exchange with external air, the heat source which produces | generates warm water, and the pump which circulates a heat medium are connected to the heat medium piping 11 and / or 21. The heat source is not particularly limited, and examples thereof include automobile engines, cogeneration equipment such as gas engines and gas turbines, and fuel cells. When used for automobiles, automobile engines and automobile fuel cells are preferable examples of heat sources. As mentioned.
[0044]
The operation method of the adsorption heat pump will be described with reference to FIG. In the first stroke, the control valves 31 and 34 are closed, the control valves 32 and 33 are released, and the regeneration process is performed in the adsorption tower 1 and the adsorption process is performed in the adsorption tower 2. Further, the switching valves 115, 116, 215, and 216 are operated, and hot water is circulated through the heat medium pipe 11 and cooling water is circulated through the heat medium pipe 21.
[0045]
When the adsorption tower 2 is cooled, cooling water cooled by exchanging heat with the outside air, river water or the like by a heat exchanger such as a cooling tower is introduced through the heat medium pipe 21 and is usually cooled to about 30 to 40 ° C. The Moreover, the water in the evaporator 4 evaporates by opening operation of the control valve 32, flows into the adsorption tower 2 as water vapor, and is adsorbed by the adsorbent. Water vapor movement 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 in the adsorption tower and the temperature of the cold water generated by the evaporator, the adsorption-side relative vapor pressure φ2 (where φ2 is the equilibrium of the adsorbate at the temperature of the cold water generated by the evaporator as shown in (b) above) Is obtained by dividing the vapor pressure by the equilibrium vapor pressure of the adsorbate at the temperature of the cooling water of the adsorption tower). Φ2 is the relative vapor pressure at which the adsorbent specified in the present invention adsorbs water vapor to the maximum. It is preferable to operate to be larger. This is because when the adsorbent specified in the present invention is smaller than the relative vapor pressure at which water vapor is adsorbed at the maximum, the adsorbing capacity of the adsorbent cannot be used effectively and the operating efficiency is deteriorated. φ2 can be appropriately set depending on the environmental temperature or the like, but the adsorption heat pump is operated under a temperature condition in which the adsorption amount at φ2 is usually 0.20 or more, preferably 0.25 or more, more preferably 0.30 or more.
[0046]
The adsorption tower 1 in the regeneration step is usually heated with hot water of 40 to 100 ° C., preferably 50 to 98 ° C., more preferably 60 to 95 ° C., and has an equilibrium vapor pressure corresponding to the temperature range. It is condensed with a saturated vapor pressure at a condensation temperature of 30-40 ° C. (this is equal to the temperature of the cooling water cooling the condenser). Water vapor moves from the adsorption tower 1 to the condenser 5 and is condensed to become water. Water is returned to the evaporator 4 by the return pipe 3. From the relationship between the temperature of the cooling water of the condenser and the temperature of the hot water, the desorption side relative vapor pressure φ1 (where φ1 is the equilibrium vapor pressure of the adsorbate at the temperature of the cooling water of the condenser, as described in (a) above, It is determined by dividing by the equilibrium vapor pressure of the adsorbate at the temperature of the hot water), but φ1 can be operated so as to be smaller than the relative vapor pressure at which SAPO-34 and ZYT-6 adsorb water vapor rapidly. preferable. If φ1 is larger than the relative vapor pressure at which the water vapor adsorbing material of the present invention abruptly adsorbs water vapor, the excellent adsorption amount of the water vapor adsorbing material of the present invention cannot be used effectively. φ1 can be appropriately set depending on the environmental temperature or the like, but the adsorption heat pump is operated under a temperature condition in which the adsorption amount at φ1 is usually 0.10 or less, preferably 0.07 or less, more preferably 0.05 or less. The difference between the adsorbate adsorption amount at φ1 and the adsorbate adsorption amount 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. To drive. The above is the first step.
[0047]
In the next second step, the evaporators are similarly switched by switching the control valves 31 to 34 and the switching valves 115, 116, 215, and 216 so that the adsorption tower 1 is an adsorption process and the adsorption tower 2 is a regeneration process. From 4, it is possible to obtain cold heat, that is, cooling output. The adsorption heat pump is continuously operated by sequentially switching the first and second strokes.
[0048]
Here, the operation method in the case where two adsorption towers are installed has been described. However, by properly desorbing the adsorbate adsorbed by the adsorbent, one of the adsorption towers can maintain a state in which the adsorbate can be adsorbed. If possible, any number of adsorption towers may be installed.
The adsorbent for the adsorption heat pump of the present invention changes the adsorption amount more at a low relative vapor pressure. Therefore, various conventionally known air conditioners having an adsorbate adsorption / desorption part, specifically, dehumidification air conditioners. There is a possibility of application as an adsorbent (adsorbent for a desiccant air conditioner) of a desorption part of a so-called desiccant air conditioner. In that case, it is applicable by changing the adsorbent in the known desiccant air conditioner to the adsorbent of the present invention.
[0049]
【Example】
Example 1
In accordance with the method described in Japanese Patent Publication No. 4-37007, a CHA-type silicoaluminophosphate was produced by the following method.
To 18 g of water, 15.4 g of 85% phosphoric acid and 9.2 g of pseudoboehmite (containing 25% water, manufactured by Condea) were slowly added and stirred. Further, 10 g of water was added and stirred for 1 hour. Separately from the A liquid, a liquid in which 4.1 g of fumed silica (Aerosil 200), 11.6 g of morpholine, and 15 g of water were mixed was slowly added to the A liquid. Further, 24 g of water was added thereto and stirred for 3 hours.
[0050]
The obtained mixture was charged into a 200 cc stainless steel autoclave containing a Teflon (registered trademark) inner cylinder and allowed to react at 200 ° C. for 24 hours. After the reaction, the reaction mixture was cooled and the supernatant was removed by decantation to collect a precipitate. The obtained precipitate was washed with water three times, filtered, and dried at 120 ° C. This was calcined at 550 ° C. for 6 hours under an air stream to obtain zeolite.
[0051]
As a result of measurement of powder XRD, this zeolite was of the CHA type (framework density = 14.6 T / 1,000 Å ³ ) silicoaluminophosphate. The framework density was determined from the structure with reference to IZA's Atlas Of Zeolite Structure Types (1996, ELSEVIER). Further, when the sample was heated and dissolved in an aqueous hydrochloric acid solution and ICP analysis was performed, the composition ratio (molar ratio) of each component with respect to the total of aluminum, phosphorus and silicon in the skeleton structure was 0.13 for silicon and 0.2 for aluminum. 49 phosphorus was 0.38.
[0052]
The adsorption isotherm of this zeolite at 25 ° C. is shown in FIG. From FIG. 1, this zeolite adsorbs water vapor abruptly at a relative vapor pressure of 0.07 to 0.10, and the amount of adsorption change in the relative vapor pressure range of 0.05 to 0.20 is 0.25 g / g. I understand that.
A ²⁹ Si-MAS-NMR spectrum measurement chart of this zeolite is shown in FIG. ^{In the 29} Si- MAS- NMR spectrum, the integrated intensity area of the signal intensity of -108 ppm to -123 ppm is 9.2% with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm, and -70 ppm to -92 ppm. The integrated intensity area of the signal intensity was 52.6%.
[0053]
Example 2
The water vapor adsorption isotherm (25 ° C.) of SAPO-34 (silicon 0.03, aluminum 0.52, phosphorus 0.45 (molar ratio), manufactured by UOP LLC) is shown in FIG. It can be seen from FIG. 3 that water vapor is rapidly adsorbed at a relative vapor pressure of 0.07 to 0.10, and the amount of change in the adsorption amount in the relative vapor pressure range of 0.05 to 0.20 is 0.25 g / g. .
[0054]
SAPO-34 is a CHA-type silicoaluminophosphate, and the CHA-type framework density is 14.6 T / 1,000Å3 and the pore diameter is 3.8Å.
FIG. 4 shows a ²⁹ Si-MAS-NMR chart of SAPO-34 (manufactured by UOP LLC). From the spectrum measurement chart, in the spectrum, the integrated intensity area of the signal intensity of −108 ppm to −123 ppm is 0.6% with respect to the integrated intensity area of the signal intensity of −70 ppm to −123 ppm, and −70 ppm to −92 ppm. The integrated intensity area of the signal intensity was 85.9%.
[0055]
Example 3
After adding 72 g of aluminum isopropoxide to 128 g of water and stirring, 38.76 g of 85% phosphoric acid was added and stirred for 1 hour. After adding 1.2 g of fumed silica (Aerosil 200) to this solution, 89.3 g of 35% tetraethylammonium hydroxide (TEAOH) aqueous solution was further added and stirred for 3 hours. This mixture was charged into a 500 cc stainless steel autoclave containing a Teflon (registered trademark) inner cylinder, and reacted at 185 ° C. for 60 hours with stirring at 100 rpm. After the reaction, the mixture was cooled, and the product was separated by centrifugation, washed with water, and dried at 120 ° C. This was calcined in an air stream at 550 ° C. for 6 hours to obtain zeolite.
[0056]
As a result of measurement by powder XRD, it was a CHA type silicoaluminophosphate (framework density = 14.6 T / 1,000 ³ ). Further, when the sample was heated and dissolved in an aqueous hydrochloric acid solution and subjected to ICP analysis, the composition ratio (molar ratio) of each component to the total of aluminum, phosphorus and silicon in the skeleton structure was 0.03 for silicon and 0.2 for aluminum. 50 phosphorus was 0.47.
[0057]
The adsorption isotherm of this zeolite at 25 ° C. is shown in FIG. FIG. 5 shows that this zeolite also exhibits the same adsorption isotherm as that of the zeolite of Example 1, and rapidly adsorbs water vapor at a relative vapor pressure of 0.07 to 0.10, and a relative vapor pressure range of 0.05 to 0.00. The amount of change in the adsorption amount of 20 was 0.23 g / g.
Example 4
87.1 g of 85% phosphoric acid was added to 180 g of water, and 57.2 g of pseudoboehmite (containing 25% water, manufactured by Condea) was slowly added thereto and stirred for 2 hours. This was designated as liquid A. Separately from the liquid A, 5.04 g of fumed silica (Aerosil 200), 36.6 g of morpholine, and 240 g of water were prepared, and this was slowly added to the liquid A. Further, 46.6 g of triethylamine was added, and this was stirred for 3 hours. The composition of the gel at this time is as follows.
[0058]
Al ₂ O ₃ /0.9P ₂ O ₅ /0.2SiO ₂ /morpholine/1.1 triethylamine / 60H ₂ O
The mixture thus obtained was charged into a 1 liter stainless steel autoclave containing a fluororesin inner cylinder, reacted at 190 ° C. for 12 hours with stirring at 100 rpm, further heated to 200 ° C. and reacted for 24 hours. After the reaction, the reaction mixture was cooled and the supernatant was removed by decantation to collect a precipitate. The precipitate thus obtained was washed with water, filtered, and dried at 120 ° C. This was calcined at 560 ° C. for 6 hours under an air stream to obtain zeolite. When the powder XRD of this zeolite was measured, it was a CHA structure (framework density = 14.6T / 1,000１ ， ³ ). When the sample was heated and dissolved in an aqueous hydrochloric acid solution and obtained by ICP analysis, the composition ratio (molar ratio) of each component to the total of aluminum, phosphorus, and silicon in the skeleton structure was 0.07 for silicon and aluminum for aluminum as a result of elemental analysis. It was 0.486 and phosphorus was 0.444.
[0059]
The adsorption isotherm of this zeolite at 25 ° C. is shown in FIG. The amount of adsorption change in the relative vapor pressure range of 0.05 to 0.20 was 0.19 g / g.
²⁹ Si-MAS-NMR of this zeolite was measured under the same conditions as in Example 1. The result is shown in FIG. In this spectrum, with respect to the integrated area of the signal intensity from -70 ppm to -123 ppm, the integrated intensity area of the signal intensity from -108 ppm to -123 ppm is 0.6%, and the integrated intensity area of the signal intensity from -70 ppm to -92 ppm is It was 73.5%.
[0060]
Example 5
After 72 g of aluminum isopropoxide was added to 128 g of water and stirred, 39 g of 85% phosphoric acid was added and stirred for 1 hour. After adding 1.2 g of fumed silica (Aerosil 200) to this solution, 89 g of 35% TEAOH (tetraethylammonium hydroxide) aqueous solution was further added and stirred for 4 hours. The composition of the gel at this time is as follows.
[0061]
Al ₂ O ₃ /0.95P ₂ O ₅ /0.1SiO ₂ /1.1TEAOH/57H ₂ O
This mixture was charged into a 500 cc stainless steel autoclave containing a fluororesin inner cylinder and reacted at 180 ° C. for 48 hours while stirring at 100 rpm. After the reaction, the mixture was cooled, and the product was separated by centrifugation, washed with water, and dried at 120 ° C. This was calcined in an air stream at 550 ° C. for 6 hours to obtain zeolite. This zeolite was measured by XRD and found to have a CHA structure. In addition, as a result of elemental analysis, the composition ratio (molar ratio) of each component with respect to the total of aluminum, phosphorus, and silicon in the skeleton structure was 0.033 for silicon, 0.491 for aluminum, and 0.476 for phosphorus. The adsorption isotherm at 25 ° C. is shown in FIG. The adsorption amount change in the relative vapor pressure range of 0.05 to 0.20 was 0.24 g / g.
[0062]
Example 6
After 9 g of aluminum isopropoxide was added to 16 g of water and stirred, 5.1 g of 85% phosphoric acid was added and stirred for 1 hour. To this solution, 0.45 g of fumed silica (Aerosil 200) was added, and then 9.3 g of 35% TEAOH (tetraethylammonium hydroxide) aqueous solution was added and stirred for 2 hours. The composition of the gel at this time is as follows.
[0063]
_{Al 2 O 3 / 1P 2 O} 5 /0.3SiO 2 / 1TEAOH / 57H 2 O
This mixture was charged into a 200 cc stainless steel autoclave containing a fluororesin inner cylinder and allowed to react at 200 ° C. for 48 hours in a stationary state. After the reaction, the mixture was cooled, and the product was separated by centrifugation, washed with water, and dried at 120 ° C. This was calcined in an air stream at 550 ° C. for 6 hours to obtain zeolite. This zeolite was measured by XRD and found to have a CHA structure. As a result of elemental analysis, the composition ratio (molar ratio) of each component with respect to the total of aluminum, phosphorus, and silicon in the skeleton structure was 0.067 for silicon, 0.482 for aluminum, and 0.45 for phosphorus. The adsorption isotherm at 25 ° C. is shown in FIG. The amount of adsorption change in the relative vapor pressure range of 0.05 to 0.20 was 0.20.
[0064]
Comparative Example 1
115.3 g of 85% phosphoric acid was added to 173.4 g of water, and further 68 g of pseudoboehmite (containing 25% water; manufactured by Condea) was slowly added and stirred for 3 hours. To this, 30 g of fumed silica was added, 87.2 g of morpholine and 242.3 g of water were added, and the mixture was stirred for 4.5 hours. This was aged overnight at room temperature, charged in a 1 L stainless steel autoclave with an induction stirring type containing a Teflon (registered trademark) inner cylinder, stirred at 60 rpm, and reacted at 200 ° C. for 24 hours. After the reaction, the reaction mixture was cooled and the supernatant was removed by decantation to collect a precipitate. The precipitate thus obtained was washed with water, filtered off and dried at 120 ° C. This was calcined at 550 ° C. in an air stream to obtain zeolite. When the XRD of this zeolite was measured, it was a CHA type. Further, when the sample was heated and dissolved in an aqueous hydrochloric acid solution and analyzed by ICP, the composition ratio (molar ratio) of each component to the total of aluminum, phosphorus and silicon in the skeleton structure was 0.12 for silicon and 0.49 for aluminum. The phosphorus was 0.39.
[0065]
The adsorption isotherm of this zeolite at 25 ° C. is shown in FIG. From FIG. 6, this zeolite adsorbs water vapor rapidly from the adsorption start state where the relative vapor pressure is very low, and the amount of change in the adsorption amount in the relative vapor pressure range of 0.05 to 0.20 is only 0.1 g / g or less. I understand that there is not. Therefore, it is not suitable as an adsorbent for an adsorption heat pump using a relatively low-temperature heat source as a drive source.
[0066]
The result of Si-MAS-NMR measurement under the same conditions is shown in FIG. ^{In the 29} Si-MAS-NMR spectrum, the integrated intensity area of the signal intensity of -108 ppm to -123 ppm was 13.0% with respect to the integrated area of the signal intensity of -70 ppm to -123 ppm. Moreover, the integrated value of the signal intensity of −70 ppm to −92 ppm was 51.6%. Thus, it can be seen that if the peak intensity near -110 ppm is large, even CHA type silicoaluminophosphate is not suitable as an adsorbent.
[0067]
【The invention's effect】
As adsorbents for adsorption heat pumps, silica gel and zeolite with a low silica alumina ratio have been generally used. However, adsorbents that have been used in conventional adsorption heat pumps have insufficient adsorption / desorption capability to use a relatively low-temperature heat source as a drive source for the adsorption heat pump.
[0068]
For example, when a 13X water vapor adsorption isotherm is considered as a representative example of a 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 region higher than 0.05, It does not change. When regenerating the adsorbent, the relative humidity of the surrounding gas is lowered to remove the water once adsorbed, but it is necessary to lower the relative vapor pressure to desorb the water adsorbed on the zeolite 13X. Therefore, it is said that a heat source of 150 ° C. to 200 ° C. is necessary. In general, zeolite is excellent in water adsorption ability, but once adsorbed, adsorbate is difficult to desorb and has a drawback that a high-temperature heat source is required for regeneration.
[0069]
Recently, mesoporous molecular sieves (such as FSM-10) (JP 9-178292 A) synthesized using a micelle structure of a surfactant as a template (Japanese Patent Laid-Open No. 9-178292) and porous aluminum phosphate molecular sieves (commonly known as AlPO-5) -197439) and the like are also being studied. Mesoporous molecular sieve (FSM-10) is a promising material with a relative vapor pressure in the range of 0.20 and 0.35 and a large adsorption amount difference of 0.25 g / g (Japanese Patent Laid-Open No. 9-178292: FIG. 14). Graph 4; FSM-10). However, the amount of adsorption is small in the range of relative vapor pressure of 0.05 to 0.30, which is an example of the operation of the adsorption heat pump of the present invention. Among them, the adsorption amount change is large in the range of the relative vapor pressure of 0.15 to 0.30, but the adsorption amount difference at this time is 0.08 g / g, and the performance of the adsorption heat pump has to be inferior. . In addition, it has been pointed out that the structure collapses and the function as an adsorbent decreases when used repeatedly, and durability is an issue.
[0070]
For example, adsorption isotherm (Colloid Poly Sci 277, p83-88) of ALPO-5, which is an AFI type (framework density = 17.5T / 1,000１，3) zeolite of the porous aluminum phosphate molecular sieve shown in FIG. 1999), Fig. 1 (adsorption temperature 30 ° C.)), the adsorption amount of ALPO-5 increases rapidly in the range of relative vapor pressure 0.25 to 0.40. Although adsorption / desorption was possible in the range of 0.05 to 0.3, the change in adsorption amount in the range of relative vapor pressure 0.15 to 0.30 was 0.14 g / g.
[0071]
A silica gel type A (Fuji Silysia Chemical Co., Ltd.), known as an adsorbent suitable for an adsorption heat pump, was measured with an adsorption isotherm (Belsorb 18: Nippon Bell Co., Ltd.). The adsorption isotherm is shown in FIG. In addition, this measurement was performed on the same conditions as Example 1 of FIG. According to the adsorption isotherm of the silica gel A type in FIG. 9, the silica gel A type can obtain an adsorption amount substantially proportional to the relative water vapor pressure in the range of the relative water vapor pressure of 0 to 0.7. However, in the same relative vapor pressure range of 0.15 to 0.30 as that of mesoporous molecular sieve and porous aluminum phosphate molecular sieve, the amount of adsorption of A-type silica gel is only 0.08 g / g. Adsorption heat pumps using silica gel as an adsorbent have been commercialized, but the apparatus must be large due to the small difference in adsorption amount.
[0072]
In the present invention, the skeleton structure contains aluminum, phosphorus and silicon, and the integrated intensity area of the signal intensity of -108 ppm to -123 ppm in the ²⁹ Si-MAS-NMR spectrum is relative to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm. With a water vapor adsorbent of less than 10%, the difference in moisture adsorption due to adsorption / desorption of the adsorbent is large, and the adsorbent can be regenerated (desorbed) at a low temperature. Can be used to efficiently drive the adsorption heat pump. That is, according to the adsorbent of the present invention, an adsorption heat pump that is driven by a relatively low-temperature heat source of 100 ° C. or less can be provided.
[Brief description of the drawings]
1 is a water vapor adsorption isotherm of Example 1. FIG.
2 is a ²⁹ Si-MAS-NMR spectrum measurement chart of Example 1. FIG.
3 is a water vapor adsorption isotherm of Example 2. FIG.
4 is a ²⁹ Si-MAS-NMR spectrum measurement chart of Example 2. FIG.
5 is a water vapor adsorption isotherm of Example 3. FIG.
6 is a water vapor adsorption isotherm of Comparative Example 1. FIG.
7 is a ²⁹ Si-MAS-NMR spectrum measurement chart of Comparative Example 1. FIG.
FIG. 8 is a water vapor adsorption isotherm of A-type silica gel.
FIG. 9 is a water vapor adsorption isotherm of ALPO-5.
FIG. 10 is a conceptual diagram of an example of an adsorption heat pump according to the present invention.
11 is a ²⁹ Si-MAS-NMR spectrum measurement chart of Example 4. FIG.
12 is a water vapor adsorption isotherm of Example 4. FIG.
13 is a water vapor adsorption isotherm of Example 5. FIG.
14 is a water vapor adsorption isotherm of Example 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Adsorption tower 2 Adsorption tower 3 Adsorbate piping 4 Evaporator 5 Condenser 11 Heating 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 Heating 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 unit 301 Pump 41 Cold water piping (inlet)
42 Cold water piping (exit)
51 Cooling water piping (inlet)
52 Cooling water piping (exit)

Claims (15)

An adsorbent, an adsorption / desorption part having an adsorbent for adsorbing and desorbing the adsorbate, an evaporation part for evaporating the adsorbate connected to the adsorption / desorption part, and condensing the adsorbate connected to the adsorption / desorption part An operation method of an adsorption heat pump including a condensing unit,
The adsorbent is a water vapor adsorbent containing zeolite, the zeolite contains aluminum, phosphorus and silicon in the framework structure, and a signal intensity of −108 ppm to −123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite Is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm,
A method for operating an adsorption heat pump, wherein a temperature of a heating medium heated when the adsorbate is desorbed from the adsorbent to regenerate the adsorbent is 100 ° C or less. An adsorbent, an adsorption / desorption part having an adsorbent for adsorbing and desorbing the adsorbate, an evaporation part for evaporating the adsorbate connected to the adsorption / desorption part, and condensing the adsorbate connected to the adsorption / desorption part An operation method of an adsorption heat pump including a condensing unit,
The adsorbent is a water vapor adsorbent containing zeolite, the zeolite contains aluminum, phosphorus and silicon in the framework structure, and a signal intensity of −108 ppm to −123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite Is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm,
The adsorbate is desorbed from the adsorbent and the temperature of the heating medium heated when regenerating the adsorbent is 60 to 95 ° C, and the temperature of the condensing part is 30 to 40 ° C. Operation method of adsorption heat pump. The zeolite has an integrated intensity area with a signal intensity of -70 ppm to -92 ppm in a ²⁹ Si-MAS-NMR spectrum of 25% or more with respect to an integrated intensity area of a signal intensity of -70 ppm to -123 ppm. The operation method of the adsorption heat pump of 2. The abundance ratio of aluminum, phosphorus and silicon atoms contained in the framework structure of the zeolite is represented by the following formulas (1), (2) and (3)
0.001 ≦ x ≦ 0.3 (1)
(In the formula, x represents the molar ratio of silicon to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ y ≦ 0.6 (2)
(Wherein y represents the molar ratio of aluminum to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ z ≦ 0.6 (3)
(Wherein z represents the molar ratio of phosphorus to the total of aluminum, phosphorus and silicon in the skeleton structure)
The operation method of the adsorption heat pump according to any one of claims 1 to 3.   The operation method of the adsorption heat pump according to any one of claims 1 to 4, wherein the zeolite has a structure represented by CHA in a code defined by International Zeolite Association (IZA).   When the zeolite has a relative vapor pressure of 0.15 or more in the range of relative vapor pressure of 0.05 or more and 0.30 or less in the water vapor adsorption isotherm, the relative amount of adsorption of water is 0.18 g / g or more. It has a pressure range, The operation method of the adsorption heat pump of any one of Claims 1-5.   The operation method of the adsorption heat pump according to any one of claims 1 to 6, wherein the zeolite has a water vapor adsorption amount of 0.15 g / g or less at a water vapor adsorption isotherm at a relative vapor pressure of 0.05.   The operation method of the adsorption heat pump according to any one of claims 1 to 7, wherein a content of the zeolite is 60% by weight or more of the entire water vapor adsorbent. Adsorbate desorption unit having an adsorbent to desorb the adsorbate, the evaporation unit for the evaporation of the consolidated been adsorbate suction desorption unit, and linked condensation of adsorbate suction desorption unit An adsorption heat pump with a condensing part to perform,
The temperature of the heat medium for heating the pre-Symbol adsorbent when reproducing the adsorbent to desorb the adsorbate and 100 ° C. or less,
The adsorbent is a water vapor adsorbent containing zeolite, the zeolite contains aluminum, phosphorus and silicon in the framework structure, and a signal intensity of −108 ppm to −123 ppm in the ²⁹ Si-MAS-NMR spectrum of the zeolite Is 10% or less with respect to the integrated intensity area of the signal intensity of -70 ppm to -123 ppm,
The abundance ratio of aluminum, phosphorus and silicon atoms contained in the framework structure of the zeolite is represented by the following formulas (1), (2) and (3)
0.001 ≦ x ≦ 0.3 (1)
(In the formula, x represents the molar ratio of silicon to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ y ≦ 0.6 (2)
(Wherein y represents the molar ratio of aluminum to the total of aluminum, phosphorus and silicon in the skeleton structure)
0.3 ≦ z ≦ 0.6 (3)
(Wherein z represents the molar ratio of phosphorus to the total of aluminum, phosphorus and silicon in the skeleton structure)
Satisfied,
When the zeolite has a relative vapor pressure of 0.15 or more in the range of relative vapor pressure of 0.05 or more and 0.30 or less in the water vapor adsorption isotherm, the relative amount of adsorption of water is 0.18 g / g or more. and it has a pressure range, the adsorption heat pump, characterized in that. The zeolite has an integrated intensity area of a signal intensity of -70 ppm to -92 ppm in a ²⁹ Si-MAS-NMR spectrum of 25% or more with respect to an integrated intensity area of a signal intensity of -70 ppm to -123 ppm. The adsorption heat pump described. The adsorption heat pump according to claim 9 or 10, wherein the zeolite has a structure represented by CHA in a code defined by International Zeolite Association (IZA). The adsorption heat pump according to any one of claims 9 to 11, wherein the zeolite has a water vapor adsorption isotherm of 0.15 g / g or less at a water vapor adsorption isotherm at a relative vapor pressure of 0.05. The temperature of the heat medium heated when desorbing the adsorbate from the adsorbent to regenerate the adsorbent is 60 to 95 ° C, and the temperature of the condensing part is 30 to 40 ° C. The adsorption heat pump of any one of these. The adsorption heat pump according to any one of claims 9 to 13, wherein a high temperature heat source of 60 to 95 ° C and a low temperature heat source of 30 to 40 ° C are used for desorption of the adsorbate in the adsorption / desorption portion. A vehicle air conditioner, wherein the adsorption heat pump according to any one of claims 9 to 14 is used for air conditioning in a vehicle compartment.

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