JP2016161150A - Adsorption heat pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adsorption heat pump using zeolite type adsorption material in which water vapor acting as adsorbate during desorption operation can be sufficiently processed in desorption, adsorption-desorption characteristics are sufficiently realized to enable cold heat output to be increased further.SOLUTION: An adsorption heat pump has a flow passage configuration in which, when an adsorption operation is carried out at one adsorption-desorption part 1A and a desorption operation is carried out at the other adsorption-desorption part 1B, cooling water is supplied to a condensing part 3 and one adsorption-desorption part 1A in sequence and hot water is circulated to the other adsorption-desorption part 1B, and has a flow passage configuration in which, when a desorption operation is carried out at one adsorption-desorption part 1A and an adsorption operation is carried out at the other adsorption-desorption part 1B, cooling water is supplied to the condensing part 3 and the other adsorption-desorption part 1B in sequence and hot water is circulated to one adsorption-desorption part 1A, and further adsorption material held at each of adsorption elements is a specified zeolite realizing a superior adsorption performance even at a relatively high temperature.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an adsorption heat pump, and more particularly, to an adsorption heat pump that performs heat transfer using an adsorption / desorption function of adsorbate by an adsorbent, and can further improve the cold output. .

  As is well known, the adsorption heat pump is a system that performs heat transfer using the adsorption / desorption function of the adsorbate by the adsorbent, and schematically shows an adsorption element that holds the adsorbent as shown in FIGS. 3 and 4. A pair of adsorption / desorption units (adsorption towers) 1A and 1B that adsorb and desorb an adsorbate such as water by 1 and an evaporation unit (evaporator) that obtains cold heat by evaporating the adsorbate in accordance with the adsorption operation in these adsorption / desorption units 2 and a condensing unit (condenser) 3 for condensing the adsorbate vapor desorbed by the adsorption / desorption units 1A and 1B and supplying the vapor to the evaporation unit 2 and desorbing at the adsorption / desorption units 1A and 1B In operation, by using low-temperature exhaust heat discharged from an internal combustion engine or the like, the evaporator 2 can obtain cold heat used for air conditioning or the like (see Patent Document 1).

  In the adsorption heat pump as described above, in order to simplify and reduce the size of the apparatus, it is used in the cooling unit used in the adsorption operation in the adsorption / desorption units 1A and 1B and the condensing unit 3 for condensing the adsorbate vapor. Cooling water is circulated sequentially. That is, as shown in FIG. 3, when the adsorption operation is performed in the adsorption / desorption unit 1A, the cooling water generated in the cooling facility 4A is supplied to the adsorption element 1 of the adsorption / desorption unit 1A through the flow path 81, thereby Adsorption by the adsorbent is promoted while removing heat, and then the cooling water is supplied to the condensing unit 3 through the flow path 82, so that the other adsorbing / desorbing unit 1 </ b> B in the desorption process is introduced into the condensing unit 3. The adsorbate vapor is condensed and liquefied, and the cooling water used for cooling in the condensing unit 3 is returned to the cooling facility 4 </ b> A through the flow path 83.

  In addition, as shown in FIG. 4, when the adsorption operation is performed in the adsorption / desorption unit 1 </ b> B, the cooling water generated in the cooling facility 4 </ b> A is exchanged by the channel 84 by switching the channel configuration with the switching valve. Adsorption element 1 is supplied to promote adsorption, and then the cooling water is supplied to condensing unit 3 through channel 85 to condense and liquefy the adsorbate vapor, and cooling used for cooling in condensing unit 3 Water is returned to the cooling facility 4 </ b> A through the flow path 83. In addition, when performing desorption operation in the adsorption element 1, warm water is circulated through the flow paths 61 and 62 from the heat source 4B that performs heat exchange and heat exchange to the adsorption / desorption unit 1B, and the adsorption / desorption unit 1A On the other hand, hot water is circulated through the flow paths 63 and 64. The cold heat obtained in the evaporation unit 2 can be taken out by circulating, for example, water through the cold heat utilization device 9 through the flow paths 71 and 72. In the figure, reference numerals 21 and 22 denote dampers that partition the adsorption / desorption parts 1A and 1B and the evaporation part 2, reference numerals 31 and 32 denote dampers that partition the adsorption / desorption parts 1A and 1B and the condensation part 3, and , P1 to P3 indicate pumps for fluid transfer.

  On the other hand, as an adsorbent used in the adsorption / desorption part of the adsorption heat pump as described above, in recent years, the adsorbate can be adsorbed / desorbed with a large adsorption amount and a relatively small temperature difference instead of the conventional pellet-like silica gel. Various zeolite-based adsorbents have been studied. Among these, aluminophosphates (ALPO) containing at least Al and P in the skeleton structure as zeolite that can easily adsorb adsorbate vapor and easily desorb at low temperatures. The use of zeolite) has also been proposed. In addition, as for the adsorption element that holds the adsorbent in the adsorption / desorption part, there are also plate fin type and corrugated fin type elements that have a large adsorbent holding amount and can easily convey the cold heat necessary for adsorption and the heat necessary for desorption. Various proposals have been made (see Patent Documents 2 and 3).

Japanese Patent No. 4654580 Japanese Patent No. 4542738 Japanese Patent No. 5333626

  By the way, zeolites such as aluminophosphates themselves have a large difference in the amount of adsorption during adsorption and desorption, which is expected to reduce the size of the adsorption heat pump and improve the cold output. It is in the present situation that the adsorption / desorption characteristics possessed cannot be fully exploited. That is, since the adsorption heat generated when adsorbing and desorbing the zeolite adsorbing water vapor is larger than that of a conventional adsorbent such as silica gel, the zeolite-based adsorbent is used as a heat exchange coil in the condensing section. The temperature of the flowing cooling water increases. Therefore, the adsorbate in the condensing part cannot be sufficiently condensed, so that the adsorbent of the adsorption / desorption part (adsorption element) that performs the desorption operation moves to the next adsorption cycle in a state of insufficient desorption, and as a result, It is difficult to fully exhibit the cold heat output of the adsorption heat pump.

  The present invention has been made in view of the above circumstances, and its purpose is an adsorption heat pump using a zeolite-based adsorbent having a large difference in adsorption amount between adsorption and desorption, and as an adsorbate in the desorption operation. It is an object of the present invention to provide an adsorption heat pump capable of sufficiently desorbing water vapor and sufficiently exhibiting adsorption / desorption characteristics to further increase the cold output.

  In order to solve the above problems, in the present invention, the cooling water generated at the cooling facility is first supplied to the condensing unit, and then sequentially supplied to the adsorption elements of the adsorption / desorption unit that performs the adsorption operation. , Improving the condensation efficiency of the adsorbate in the condensing part, thereby improving the desorption function in the adsorption element of the adsorption / desorption part that performs desorption operation, and relatively high as an adsorbent to be held in the adsorption element of the adsorption / desorption part By selecting a specific aluminophosphate that exhibits excellent adsorption performance even at temperatures, the difference in the amount of adsorption between the adsorption element and the desorption was further increased. In other words, in the desorption operation, the operation can be performed in a state where the adsorbate of the adsorbent is completely desorbed.

  That is, the gist of the present invention is an adsorption heat pump that performs heat transfer using the adsorption / desorption function of the adsorbate by the adsorbent, and includes at least a pair of adsorption / desorption each having an adsorption element that holds the adsorbent. , An evaporating unit that obtains cold heat by evaporating the adsorbate in accordance with the adsorption operation in these adsorbing and desorbing units, and a condensing unit that condensates and liquefies the adsorbate vapor desorbed in each adsorbing and desorbing unit When the adsorption operation is performed at one of the adsorption / desorption sections and the desorption operation is performed at the other adsorption / desorption section, the cooling water generated by the cooling equipment is sequentially supplied to the condensation section and one of the adsorption / desorption sections. The flow path is configured so that the hot water generated by the heat source is circulated to the other adsorption / desorption part, and the desorption operation is performed at one of the adsorption / desorption parts. When the adsorption operation is performed at the cooling water, the cooling water generated by the cooling equipment is condensed on the other side. The flow path is configured so that the hot water generated in the heat source is circulated to one of the adsorption / desorption parts, and is supplied to each adsorption element. The adsorbent has an adsorption amount at a relative vapor pressure of 0.05 on a water vapor adsorption isotherm at 40 ° C. of 0.1 g / g or less and a relative vapor pressure of 0.05 or more and 0.10 or less. The adsorption heat pump is characterized by being a zeolite having a relative vapor pressure region in which the change in the amount of adsorption of water when the relative vapor pressure changes by 0.05 is 0.15 g / g or more.

  According to the adsorption heat pump of the present invention, the cooling water generated in the cooling facility is first supplied to the condensing unit, and then sequentially supplied to the adsorbing elements of the adsorption / desorption unit that performs the adsorption operation, thereby adjusting the temperature of the condensing unit. In order to maintain a lower temperature, the adsorption element of the adsorption / desorption part that performs the desorption operation can further promote the desorption of the adsorbate to be in a completely desorbed state, and excellent adsorption even at a relatively high temperature Since a specific zeolite that exhibits its function is used, the difference in adsorption amount during adsorption and desorption can be further increased. As a result, the amount of adsorbate evaporated in the evaporation section is increased, further increasing the cooling output. Can be increased.

It is a flowchart which shows the main structures and the operating method of the adsorption heat pump which concerns on this invention. It is a flowchart which shows the state which switched adsorption / desorption operation in the adsorption heat pump of FIG. It is a flowchart which shows the main structures and the operating method of the conventional adsorption heat pump. It is a flowchart which shows the state which switched adsorption / desorption operation in the adsorption heat pump of FIG. It is a water vapor adsorption isotherm showing the adsorption / desorption characteristics of the adsorbent used in the present invention.

  An embodiment of an adsorption heat pump according to the present invention will be described with reference to the drawings. In addition, this invention is not limited to the following embodiment, unless the meaning is exceeded.

First, the zeolite used as the adsorbent in the present invention will be described. The zeolite used in the present invention has an adsorption amount at a relative vapor pressure of 0.05 on a water vapor adsorption isotherm at 40 ° C. of 0.1 g / g or less, and a relative vapor pressure of 0.05 or more and 0.10. The zeolite is not particularly limited as long as it is a zeolite having a relative vapor pressure range of 0.15 g / g or more when the relative vapor pressure changes by 0.05 in the following range, For example, a zeolite having a molar ratio of aluminum, phosphorus, and silicon having a skeleton structure represented by the following formulas (I), (II), and (III).
0.001 ≦ x ≦ 0.3 (I)
(In the formula, x represents the molar ratio of silicon to the total of silicon, aluminum and phosphorus in the skeleton structure.)
0.3 ≦ y ≦ 0.6 (II)
(In the formula, y represents the molar ratio of aluminum to the total of silicon, aluminum and phosphorus in the skeleton structure.)
0.3 ≦ z ≦ 0.6 (III)
(In the formula, z represents the molar ratio of phosphorus to the total of silicon, aluminum, and phosphorus in the skeleton structure.)
In addition, the framework density, which is a parameter reflecting the crystal structure, is expressed by the International Zeolite Association (hereinafter referred to as “IZA”) in “ATLAS OF ZEOLITE FRAME ORK TYPE FISTH Revised Edition 2001”, preferably 10 a is .0T / 1000Å ³ or more, usually 16.0T / 1000Å ³ or less, preferably preferably not more 15.0T / 1000Å ³ or less, further, the structure of the zeolite is determined by XRD, stipulated by IZA In terms of code, AEI, AFR, AFS, AFT, AFX, AFY, AHT, CHA, DFO, ERI, FAU, GIS, LEV, LTA, VFI, AEI, AF , GIS, CHA, VFI, AFS, LTA, FAU, AFY are preferred, and most preferred zeolites having inter alia CHA structure.

  Specific examples of the CHA-type silicoaluminophosphate zeolite that is a preferred zeolite include zeolite called “SAPO-34”, AQSOA Z02 (manufactured by Mitsubishi Plastics, Inc .; registered trademark), and the like. Such a zeolite can be produced by a known hydrothermal synthesis method in which an aluminum source, a silicon source, a phosphorus source and a template are mixed, hydrothermally synthesized, and then the template is removed. The following is an example of a manufacturing method. The synthesis method of SAPO-34 is described in, for example, US Pat. No. 4,440,871.

First, an aluminum source, a silicon source, a phosphorus source and a template are mixed.
<Aluminum source>
The aluminum source is not particularly limited and usually includes aluminum alkoxides such as pseudo boehmite, aluminum isopropoxide, aluminum triethoxide, aluminum hydroxide, alumina sol, sodium aluminate and the like, and pseudo boehmite is preferred.
<Silicon source>
The silicon source is not particularly limited, and usually includes fumed silica, silica sol, colloidal silica, water glass, ethyl silicate, methyl silicate, and the like, and fumed silica is preferable.
<Phosphorus source>
As the phosphorus source, phosphoric acid is usually used, but aluminum phosphate may be used.
<Template>
The template is an important factor that determines the framework structure of the desired zeolite, and a known template may be selected and used to produce a zeolite having the desired framework structure. For example, when producing a CHA type zeolite preferably used in the present invention, the template is a method using a compound containing tetraethylammonium ions (for example, tetraethylammonium hydroxide), or (1) an alicyclic containing nitrogen as a hetero atom. Among the three groups of the heterocyclic compound, (2) cycloalkylamine, and (3) alkylamine, a method of selecting and using one or more compounds for each group from two or more groups can be mentioned. The latter method is preferred. Hereinafter, an example in which two or more types of such templates are used will be described.

(1) Alicyclic heterocyclic compound containing nitrogen as a hetero atom:
The heterocyclic ring of the alicyclic heterocyclic compound containing nitrogen as a hetero atom is usually a 5- to 7-membered ring, and preferably a 6-membered ring. The number of heteroatoms contained in the heterocycle is usually 3 or less, preferably 2 or less. The type of heteroatom is not particularly limited except nitrogen, but preferably includes oxygen in addition to nitrogen. The positions of the heteroatoms are not particularly limited, but those where the heteroatoms are not adjacent to each other are preferable. The molecular weight is usually 250 or less, preferably 200 or less, more preferably 150 or less. Examples of the alicyclic heterocyclic compound containing nitrogen as a hetero atom as described above include morpholine, N-methylmorpholine, piperidine, piperazine, N, N′-dimethylpiperazine, 1,4-diazabicyclo (2,2,2) octane. , N-methylpiperidine, 3-methylpiperidine, quinuclidine, pyrrolidine, N-methylpyrrolidone, hexamethyleneimine and the like, morpholine, hexamethyleneimine and piperidine are preferable, and morpholine is particularly preferable.

(2) Cycloalkylamine:
The number of cycloalkyl groups of the cycloalkylamine is 2 or less, preferably 1 per amine molecule. Moreover, carbon number of a cycloalkyl group is 5-7 normally, Preferably it is 6. The number of cycloalkyl cyclo rings is not particularly limited, but is usually preferably 1. Moreover, it is preferable that the cycloalkyl group has couple | bonded with the nitrogen atom of the amine compound. The molecular weight is usually 250 or less, preferably 200 or less, more preferably 150 or less. Examples of the cycloalkylamine include cyclohexylamine, dicyclohexylamine, N-methylcyclohexylamine, N, N-dimethylcyclohexylamine, and cyclohexylamine is preferable.

(3) Alkylamine:
The alkyl group of the alkylamine is a chain alkyl group, and any number may be contained in one amine molecule, but three is particularly preferable. The number of carbon atoms of the alkyl group is preferably 4 or less, and the total number of carbon atoms of all alkyl groups in one molecule is more preferably 10 or less. The molecular weight is usually 250 or less, preferably 200 or less, more preferably 150 or less. Examples of the alkylamine as described above include di-n-propylamine, tri-n-propylamine, tri-isopropylamine, triethylamine, triethanolamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, N-methyldiethanolamine, N-methylethanolamine, di-n-butylamine, neopentylamine, di-n-pentylamine, isopropylamine, t-butylamine, ethylenediamine, di-isopropyl-ethylamine, N-methyl-n-butylamine Di-n-propylamine, tri-n-propylamine, tri-isopropylamine, triethylamine, di-n-butylamine, isopropylamine, t-butylamine, ethylenediamine, di-isopropyl-ethyl Triethanolamine, N- methyl -n- butylamine are preferred, triethylamine being particularly preferred.

Preferred combinations of templates (1) to (3):
As a preferable combination, two or more kinds from morpholine, triethylamine and cyclohexylamine, more preferably morpholine and triethylamine are included. The mixing ratio of each group of these templates needs to be selected according to conditions. When mixing two templates, the molar ratio of the two templates to be mixed is usually 1:20 to 20: 1, preferably 1:10 to 10: 1, more preferably 1: 5 to 5: 1. It is. When mixing three templates, the molar ratio of the third template is usually from 1:20 to 20: 1, preferably from 1:10 to the two templates mixed in the above molar ratio. 10: 1, more preferably 1: 5 to 5: 1. Although other templates may be contained, the other templates are usually 20% or less in molar ratio with respect to the whole template, and preferably 10% or less.

Synthesis of zeolite by hydrothermal synthesis:
An aqueous gel is prepared by mixing the silicon source, aluminum source, phosphorus source, template and water described above. The mixing order is not limited and may be appropriately selected depending on the conditions to be used. Usually, however, a phosphorus source and an aluminum source are first mixed with water, and then a silicon source and a template are mixed therewith. As for the composition of the aqueous gel, when the silicon source, the aluminum source and the phosphorus source are expressed by the molar ratio of the oxide, the value of SiO ₂ / Al ₂ O ₃ is usually larger than 0 and not larger than 0.5, preferably 0.4 or less, more preferably 0.3 or less. The ratio of P ₂ O ₅ / Al ₂ O ₃ is usually 0.6 or more, preferably 0.7 or more, more preferably 0.8 or more, usually 1.3 or less, preferably 1.2 or less, Preferably it is 1.1 or less.

The composition of the zeolite obtained by hydrothermal synthesis has a correlation with the composition of the aqueous gel, and the composition of the aqueous gel may be appropriately set in order to obtain a zeolite having a desired composition. The total amount of the template is a molar ratio of the template to Al ₂ O ₃ and is usually 0.2 or more, preferably 0.5 or more, more preferably 1 or more, and usually 4 or less, preferably 3 or less, more preferably 2.5 or less. In addition, the mixing ratio of two or more templates needs to be appropriately selected according to the conditions. For example, when morpholine and triethylamine are used, the molar ratio of morpholine / triethylamine is 0.05 to 20, preferably 0.1. 10, more preferably 0.2 to 9. The order of mixing one or more templates selected from each of the two or more groups is not particularly limited, and after preparing the template, it may be mixed with other substances, and each template may be mixed with other substances. And may be mixed.

The ratio 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. The pH of the aqueous gel is usually 5 or more, preferably 6 or more, more preferably 6.5 or more, and is usually 10 or less, preferably 9 or less, more preferably 8.5 or less. In addition, you may coexist components other than the above in aqueous gel if desired. Examples of such components include hydrophilic organic solvents such as hydroxides and salts of alkali metals and alkaline earth metals, and alcohols. The proportion of coexistence is usually 0.2 or less, preferably 0.1 or less in terms of molar ratio with respect to Al ₂ O _{3 in} the case of hydroxides or salts of alkali metals or alkaline earth metals. In the case of a hydrophilic organic solvent, the molar ratio with respect to water is usually 0.5 or less, preferably 0.3 or less.

  The aqueous gel is placed in a pressure vessel, and hydrothermal synthesis is performed by maintaining a predetermined temperature under stirring or standing under self-generated pressure or gas pressure that does not inhibit crystallization. The reaction temperature of hydrothermal synthesis is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 150 ° C. or higher, and usually 300 ° C. or lower, preferably 250 ° C. or lower, more preferably 220 ° C. or lower. The reaction time is usually 2 hours or more, preferably 3 hours or more, more preferably 5 hours or more, and is usually 30 days or less, preferably 10 days or less, more preferably 4 days or less. The reaction temperature may be constant during the reaction or may be changed stepwise.

  The product is separated after the hydrothermal synthesis, but the method for separating the product is not particularly limited. Usually, it is separated by filtration, decantation, etc., washed with water, and dried at a temperature of room temperature to 150 ° C. or lower to obtain a zeolite containing the product template. And although a template is removed from the zeolite containing a template, the method is not specifically limited. Usually, it is baked at a temperature of 400 ° C. to 700 ° C. in an atmosphere of air or oxygen-containing inert gas or inert gas, or extracted with a solvent such as an aqueous ethanol solution or HCl-containing ether. The organic substance contained can be removed.

By the above production method, a zeolite having the following abundance ratios of aluminum, phosphorus, and silicon having a skeleton structure can be synthesized. The abundance ratio of aluminum, phosphorus and silicon atoms in the zeolite is represented by the following formulas (I), (II) and (III).
0.001 ≦ x ≦ 0.3 (I)
(In the formula, x represents the molar ratio of silicon to the total of silicon, aluminum and phosphorus in the skeleton structure.)
0.3 ≦ y ≦ 0.6 (II)
(In the formula, y represents the molar ratio of aluminum to the total of silicon, aluminum and phosphorus in the skeleton structure.)
0.3 ≦ z ≦ 0.6 (III)
(In the formula, z represents the molar ratio of phosphorus to the total of silicon, aluminum, and phosphorus in the skeleton structure.)

  According to the above production method, the molar ratio of silicon to the total of aluminum, phosphorus, and silicon in the skeleton structure can be controlled at 30% or less, and the molar ratio of silicon, which has been difficult until now with amine templates, is 9% or less, It is also possible to synthesize zeolite of preferably 8.7% or less, more preferably 8.5% or less.

That is, according to the above production method, a zeolite having a silicon presence ratio represented by the following formula (IV), particularly the following formula (V), and further represented by the following formula (VI) can be produced. Particularly preferred.
0.001 ≦ x ≦ 0.09 (IV)
0.005 ≦ x ≦ 0.087 (V)
0.01 ≦ x ≦ 0.085 (VI)
(In the formula, x is as defined above.)

  SAPO having a desired Si content can be synthesized by using a combination of amines as shown in the present invention as a template and controlling the Si content in the starting gel as described above. The atomic ratio is determined by elemental analysis. Elemental analysis is obtained by heating and dissolving a sample with an aqueous hydrochloric acid solution and then analyzing by ICP analysis.

  In the case of a method using two or more types of templates, the reason why SAPO with a low Si content can be synthesized is not clear, but the following is presumed. For example, when synthesizing a SAPA having a CHA type structure, an alicyclic heterocyclic compound containing nitrogen as a heteroatom, for example, morpholine, as described above, can be synthesized relatively easily if it has a high Si content. Although it is possible, if it tries to synthesize | combine a thing with little Si content, a dense component and an amorphous component will be able to be increased. In addition, as shown above, alkylamines such as triethylamine can be synthesized under limited conditions, but usually SAPOs having various structures are likely to be mixed. However, conversely, it is not a dense component or an amorphous component, and tends to have a crystalline structure. In addition, cycloalkylamine, for example, cyclohexylamine, can easily form SAPA having a CHA structure when the Si content is high, and can easily form SAPO having an ERI structure under a certain condition and rarely becomes a dense component. That is, each template has a characteristic for deriving a CHA type structure, a characteristic for promoting crystallization of SAPO, and the like under limited conditions. By combining these features, it is considered that a synergistic effect was exhibited, and an effect that could not be realized alone was exhibited.

  When used as a water vapor adsorbent, the zeolite having the above structure can be used together with a metal oxide such as silica, alumina and titania, a binder component such as clay, and a component having high thermal conductivity. At this time, the zeolite content is 60% by weight or more of the entire adsorbent, preferably 70% or more, and more preferably 80% or more. Further, the Si content can be controlled by the above-described production method, thereby making it possible to produce zeolite having adsorption / desorption characteristics under various conditions.

  As described above, the zeolite used in the present invention has a water vapor adsorption isotherm of 40 ° C., the adsorption amount at a relative vapor pressure of 0.05 is 0.1 g / g or less, and the relative vapor pressure is 0.05 or more. When the relative vapor pressure changes by 0.15 within a range of 0.25 or less, the change in the amount of adsorption of water has a relative vapor pressure range of 0.15 g / g or more (see FIG. 5). Further, in the water vapor adsorption isotherm at 55 ° C., the amount of adsorption at a relative vapor pressure of 0.03 is 0.1 g / g or less, and the relative vapor pressure is within a range of 0.03 to 0.20. What has the relative vapor pressure range whose water adsorption amount change is 0.15 g / g or more when a pressure changes 0.15 is preferable.

  Since zeolite having this property can desorb the adsorbate at 100 ° C. or lower, it can be used as a water vapor adsorbent having excellent adsorption / desorption properties. Such characteristics indicate that adsorption is possible under a wide range of conditions from low temperature to high temperature, from low humidity to high humidity, and that desorption can be performed at a relatively low temperature, which is suitable as an adsorbent for a heat pump. The zeolite as described above is disclosed in, for example, Japanese Patent No. 412287 and Japanese Patent No. 5485505.

  Next, the adsorption heat pump of the present invention will be described. The adsorption heat pump of the present invention is an adsorption heat pump that performs heat transfer using the adsorption / desorption function of adsorbates such as water and alcohols by an adsorbent, and as shown in FIGS. 1 and 2, for example, an airtight housing. By separating the inside of the body into a plurality of parts, the adsorption / desorption parts 1A, 1B, the evaporation part 2 and the condensation part 3 are configured. That is, the adsorption heat pump of the present invention is accompanied by at least a pair of adsorption / desorption parts 1A and 1B for adsorbing and desorbing adsorbate by the adsorption element 1 holding an adsorbent, and an adsorption operation at these adsorption / desorption parts 1A and 1B. The evaporation unit 2 that obtains cold heat by evaporation of the adsorbate and the condensing unit 3 that condensates and vaporizes the adsorbate vapor desorbed by the adsorption / desorption units 1A and 1B and returns to the evaporation unit 2 are provided.

  A plurality of pairs of the adsorption / desorption portions 1A and 1B may be arranged, and the adsorption element 1 is accommodated in each of the adsorption / desorption portions 1A and 1B. The adsorption element 1 is an element having a heat exchanger structure and is configured by applying an adsorbent on the surface or filling the gap with an adsorbent, and as such an adsorbent element 1, from the viewpoint of heat exchange efficiency For example, an element having a fin tube type heat exchanger structure is suitable. The finned tube-type adsorbing element 1 is configured by penetrating through a pipe line made of a copper pipe through which cooling water or hot water as a heat medium flows with respect to a large number of flat aluminum fins arranged in parallel and in parallel. The above-mentioned zeolite-based adsorbent (“AQSOA Z02” (registered trademark) manufactured by Mitsubishi Plastics) is fixed to the surface of the aluminum fin with an epoxy-based binder. Here, an epoxy-based binder was used. However, it may be either inorganic or organic, preferably organic, but is not limited to epoxy.

  The evaporating unit 2 is configured to accommodate a heat exchange coil (pipe), and the outlet of the heat exchange coil is connected to a cold utilization device 9 as a load for an adsorption heat pump such as a heat exchanger of an air conditioner. A flow path 71 for supplying cold water is connected, and a flow path 72 for returning the cold water from the cold heat utilization device 9 to the heat exchange coil is connected to the inlet of the heat exchange coil. Reference P3 indicates a pump for transferring cold water. That is, the evaporation unit 2 is configured such that the adsorbate condensed and liquefied in the condensing unit 3 flows (not shown). In the evaporation unit 2, the adsorbate adhering to the heat exchange coil has a low heat generation temperature. It is designed to produce cold water.

  The condensing unit 3 is configured to accommodate a heat exchange coil (pipe), and a flow path 51 for supplying cooling water from a cooling facility 4A such as a cooling tower is connected to the inlet of the heat exchange coil. ing. Reference sign P1 represents a pump for cooling water transfer. Further, as shown in FIG. 1, at the outlet of the heat exchanging coil of the condensing unit 3, when the adsorption operation is performed in the adsorption / desorption unit 1A, the cooling water used in the condensation unit 3 is adsorbed by the adsorption / desorption unit 1A. A flow path 52 to be supplied to the element 1 is connected, and the front end side of the flow path 52 is connected to one end of the conduit of the adsorption element 1 through a switching valve. Furthermore, a flow path 53 for returning the cooling water used in the adsorption element to the cooling facility 4A is connected to the other end of the pipe of the adsorption element 1 of the adsorption / desorption portion 1A via a switching valve.

  On the other hand, as shown in FIG. 2, at the outlet side of the heat exchange coil of the condensing unit 3, when the adsorption operation is performed in the adsorption / desorption unit 1 </ b> B, the cooling water used in the condensation unit 3 is extracted from the adsorption / desorption unit 1 </ b> B. A flow path 54 for supplying to the adsorption element 1 is provided to be branched from the flow path 52, and the front end side of the flow path 54 is connected to one end of the pipe line of the adsorption element 1 via a switching valve. It is connected. Furthermore, the other end of the pipe of the adsorption element 1 of the adsorption / desorption portion 1B is connected to a flow path 55 for returning the cooling water used in the adsorption element to the cooling facility 4A via a switching valve. That is, as shown in FIGS. 1 and 2, in the adsorption heat pump, the cooling water generated in the cooling facility 4A is circulated to either the adsorption element 1 of the adsorption / desorption part 1A or 1B by the operation of the switching valve. Has been made.

  Further, hot water is supplied to the adsorption / desorption portions 1A and 1B when performing the desorption operation with the adsorption element 1 of these adsorption / desorption portions. Specifically, as shown in FIG. 1, a flow path 61 for supplying hot water generated by the heat source 4B is connected to the other end of the adsorption element 1 of the adsorption / desorption portion 1B via a switching valve. A flow path 62 for returning the hot water used in the adsorption element to the heat source 4B is connected to one end of the adsorption element 1 of the adsorption / desorption portion 1B via a switching valve. Reference numeral P2 represents a hot water transfer pump.

  Further, as shown in FIG. 2, when performing the desorption operation in the adsorption / desorption part 1A, a flow path 63 for supplying the hot water generated by the heat source 4B to the adsorption element 1 of the adsorption / desorption part 1A is provided from the flow path 61. The front end side of the flow path 63 is connected to the other end of the conduit of the adsorption element 1 via a switching valve. And the flow path 64 which returns the warm water utilized by the said adsorption | suction element to the heat source 4B is connected to the end of the adsorption | suction element 1 of the adsorption / desorption part 1A via the switching valve. That is, as shown in FIGS. 1 and 2, in the adsorption heat pump, the hot water generated by the heat source 4B is circulated to either the adsorption element 1 of the adsorption / desorption part 1A or 1B by the operation of the switching valve. ing. As the heat source 4B, cogeneration equipment such as a gas engine and a gas turbine, a fuel cell, exhaust heat from various production processes, renewable energy such as solar heat, and the like can be used.

  The adsorption / desorption units 1A and 1B and the evaporation unit 2 and the adsorption / desorption units 1A and 1B and the condensation unit 3 are configured such that adsorbate vapor flows through a damper or a gate valve. Specifically, a damper 21 is disposed on the partition walls of the adsorption / desorption portion 1A and the evaporation portion 2, a damper 22 is disposed on the partition walls of the adsorption / desorption portion 1B and the evaporation portion 2, and the adsorption / desorption portion 1A A damper 31 is disposed on the partition wall of the condensing unit 3, and a damper 32 is disposed on the partition wall of the adsorption / desorption unit 1 </ b> B and the condensing unit 3.

  That is, in the adsorption heat pump, as shown in FIG. 1, when the adsorption operation is performed in the adsorption / desorption portion 1A and the desorption operation is performed in the adsorption / desorption portion 1B, the damper 21 is opened and the damper 22 is closed, thereby evaporating. The adsorbate vapor generated in the unit 2 is introduced into the adsorption / desorption unit 1A, and at the same time, the damper 32 is opened and the damper 31 is closed, so that the adsorbate vapor desorbed in the adsorption / desorption unit 1B is condensed. 3 is introduced. In addition, as shown in FIG. 2, when the adsorption operation is performed in the adsorption / desorption unit 1B and the desorption operation is performed in the adsorption / desorption unit 1A, the damper 22 is opened and the damper 21 is closed. The adsorbate vapor thus introduced is introduced into the adsorption / desorption unit 1B, and at the same time, the damper 31 is opened and the damper 32 is closed, whereby the adsorbate vapor desorbed by the adsorption / desorption unit 1A is introduced into the condensation unit 3. It is made so that.

  Then, the operation method of said adsorption heat pump is demonstrated. In the adsorption heat pump, the adsorption and desorption operations of the adsorbate are alternately repeated in the adsorption / desorption unit 1A, and at the same time, the adsorption / desorption operation and adsorption operation of the adsorbate are alternately repeated in the adsorption / desorption unit 1B. Generate continuously.

  First, when the adsorption operation is performed in the adsorption / desorption portion 1A and the desorption operation is performed in the adsorption / desorption portion 1B, the damper 21 and the damper 32 are opened, and the damper 22 and the damper 31 are closed as shown in FIG. Then, for example, cooling water of 25 to 45 ° C. is supplied from the cooling facility 4 </ b> A to the condensing unit 3 through the channel 51, and the cooling water that has flowed through the heat exchange coil of the condensing unit 3 is further passed through the channel 52 to the adsorption / desorption unit 1 </ b> A. To the adsorption element 1. In the adsorption operation at the adsorption / desorption part 1A, the adsorbate of the evaporation part 2 evaporates, flows into the adsorption / desorption part 1A as vapor, and is adsorbed by the adsorbent. The movement of the vapor from the evaporation section 2 to the adsorption / desorption section 1A is carried out by the saturation vapor pressure at the evaporation temperature and the adsorbent temperature (generally 25 to 45 ° C, preferably 30 to 43 ° C, more preferably 35 to 40 ° C. In the evaporation unit 2, cooling according to the heat of vaporization accompanying the evaporation of the adsorbate, that is, a cooling output can be obtained.

  Adsorption side relative vapor pressure (φ2) (value obtained by dividing the equilibrium vapor pressure of the adsorbate at the chilled water temperature generated in the evaporation section 2 by the equilibrium vapor pressure of the adsorbate at the cooling water temperature of the adsorption / desorption section 1A. ) Is determined from the relationship between the temperature of the cooling water in the adsorption / desorption part 1A and the temperature of the cold water generated in the evaporation part 2, and normally the adsorption side relative vapor pressure (φ2) is the maximum adsorbent adsorbs the adsorbate vapor. It is preferable to operate so as to be larger than the relative vapor pressure. The reason is as follows. That is, when the adsorption side relative vapor pressure (φ2) is smaller than the relative vapor pressure at which the adsorbent adsorbs the adsorbate vapor to the maximum, the adsorption function of the adsorbent cannot be used effectively, and the operation efficiency is lowered. The adsorption side relative vapor pressure (φ2) can be appropriately set depending on the environmental temperature or the like.

  On the other hand, in the desorption operation in the adsorption / desorption portion 1B, the heat source 4B through the flow path 61 to the adsorption element 1 of the adsorption / desorption portion 1B is usually 53 to 100 ° C, preferably 58 to 85 ° C, more preferably 60 to 80 ° C, and more. More preferably, hot water of 60 to 75 ° C. is supplied. As a result, the adsorbent of the adsorption element 1 of the adsorption / desorption unit 1B has an equilibrium vapor pressure corresponding to the above temperature range, and the condensation temperature of the condensation unit 3 is 25 to 45 ° C. (the temperature of the cooling water that cools the condensation unit 3). The adsorbate is desorbed at the saturated vapor pressure at The desorbed adsorbate moves in a vapor state from the adsorption element 1 of the adsorption / desorption unit 1B to the condensing unit 3 and is condensed into a liquid. Then, the condensate obtained in the condensation unit 3 is circulated and supplied to the evaporation unit 2.

  The desorption side relative vapor pressure (φ1) (a value obtained by dividing the equilibrium vapor pressure of the adsorbate at the temperature of the cooling water of the condensing unit 3 by the equilibrium vapor pressure of the adsorbate at the temperature of the hot water) The desorption side relative vapor pressure (φ1) is operated so as to be smaller than the relative vapor pressure at which the adsorbent adsorbs the adsorbate vapor suddenly. Is preferred. The reason is as follows. That is, when the desorption side relative vapor pressure (φ1) is larger than the relative vapor pressure at which the adsorbent rapidly adsorbs the adsorbate vapor, the adsorption function of the adsorbent cannot be effectively used.

  The desorption side relative vapor pressure (φ1) can be appropriately set depending on the environmental temperature or the like, but the adsorption amount at the desorption side relative vapor pressure (φ1) is usually 0.14 or less, preferably 0.10 or less. It is operated under such temperature conditions. Further, the difference between the adsorbate adsorption amount at the desorption side relative vapor pressure (φ1) and the adsorbate adsorption amount at the adsorption side relative vapor pressure (φ2) is usually 0.12 g / g or more, preferably 0.135 g. / G, and more preferably 0.15 g / g or more.

  Subsequently, when the desorption operation is performed in the adsorption / desorption portion 1A and the adsorption operation is performed in the adsorption / desorption portion 1B, the damper 22 and the damper 31 are opened and the damper 21 and the damper 32 are closed as shown in FIG. Then, the cooling water similar to the above is supplied from the cooling facility 4A to the condensing unit 3 through the flow path 51, and the cooling water flowing through the heat exchange coil of the condensing unit 3 is further adsorbed by the adsorption / desorption unit 1B through the flow path 54. Supply to element 1. Further, hot water similar to steam is supplied from the heat source 4B to the adsorption element 1 of the adsorption / desorption portion 1A through the flow path 63. Thereby, in the evaporating part 2, cooling power, in other words, cooling output can be obtained. That is, the adsorption heat pump can be continuously operated by alternately repeating the adsorption operation and desorption operation of the adsorbate in the adsorption / desorption unit 1A and simultaneously repeating the adsorption operation and adsorption operation of the adsorbate in the adsorption / desorption unit 1B. it can.

  As described above, in the adsorption heat pump of the present invention, when the adsorption operation is performed in one adsorption / desorption part 1A and the desorption operation is performed in the other adsorption / desorption part 1B, the cooling water generated in the cooling facility 4A is Condensation unit 3 is sequentially supplied to adsorption element 1 of one adsorption / desorption unit 1A, returned to cooling facility 4A, and hot water generated by heat source 4B circulates to adsorption element 1 of the other adsorption / desorption unit 1B. In addition, when the desorption operation is performed in one of the adsorption / desorption portions 1A and the adsorption operation is performed in the other adsorption / desorption portion 1B, the cooling water generated in the cooling facility 4A is condensed in the condensation portion 3 The hot water generated by the heat source 4B is circulated to the adsorbing element 1 of the one adsorbing / desorbing part 1A, and is sequentially supplied to the adsorbing element 1 of the other adsorbing / desorbing part 1B and returned to the cooling facility 4A. The flow path is configured. In addition, zeolite having specific adsorption / desorption characteristics is used as the adsorbent for each adsorption element 1.

  That is, in the adsorption heat pump of the present invention, the cooling water generated by the cooling equipment 4A is first supplied to the condensing unit 3 and then sequentially supplied to the adsorption elements 1 of the adsorption / desorption unit 1A (1B) that performs the adsorption operation. Thus, in order to maintain the temperature of the condensing unit 3 at a lower temperature, the adsorption element 1 of the adsorption / desorption unit 1B (1A) that performs the desorption operation further promotes desorption of the adsorbate adsorbed to a substantially saturated state. Because it uses a specific zeolite that can be completely desorbed and exhibits an excellent adsorption function even at relatively high temperatures, the difference in adsorption amount during adsorption and desorption can be further increased. As a result, the amount of adsorbate evaporated in the evaporation section 2 can be increased, and the cold output can be further increased.

  Further, in the adsorption heat pump of the present invention, since the same cold output can be obtained with about half the amount of adsorbent as compared with the conventional machine, it can contribute to a significant downsizing of the apparatus. Furthermore, until now, the maximum cold output of the adsorption heat pump alone has been up to about 350 kilowatts, but the adsorption heat pump of the present invention can improve the output by 1.5 times or more with an equivalent apparatus scale. This makes it more practical to use in large-scale chemical plants and the like that have not been matched with the demanded cold energy scale and have been delayed until now. Moreover, by using the adsorption heat pump of the present invention and using the excess hot wastewater generated in such a plant for regeneration (desorption) of the adsorbent, it is possible to contribute to the improvement of the energy efficiency of the entire plant. . Moreover, since the adsorption heat pump of the present invention operates sufficiently even when the cooling water temperature is about 40 ° C., it can be used in the summer when the cooling water temperature rises, and in tropical and subtropical regions.

Example 1, Comparative Example 1:
The adsorption heat pump having the structure shown in FIGS. 1 and 2 was constructed, and the cold output was confirmed using water as the adsorbate. The adsorbing element 1 is an element of a fin tube type heat exchanger composed of aluminum fins and copper pipes (pipe lines). The surface of the aluminum fins is made of Mitsubishi resin as a zeolite adsorbent; the trade name “AQSOA Z02 (Registered trademark) was fixed using an epoxy binder.

  An air-cooling type cooling tower was used as the cooling equipment 4A, and the cooling water produced by such a cooling tower was sequentially circulated to the condensing unit 3 and the adsorption / desorption unit 1A (1B) that performs the adsorption operation. The cooling water temperature at that time was 30 ° C. just before being introduced into the heat exchange coil of the condensing unit 3, and the flow rate was about 4 L / min. On the other hand, warm water was circulated from the heat source 4B to the adsorption element 1 of the adsorption / desorption part 1B (1A) for performing the desorption operation. The hot water temperature at that time was 75 ° C. just before the inlet of the pipe line of the adsorption element 1, and the flow rate was about 2 L / min. Moreover, the cold water used for the cooling use with the air-conditioning equipment was introduced into the evaporation part 2. The chilled water temperature was 10 to 11 ° C. just before entering the heat exchange coil (evaporation coil) of the evaporation unit 2, and the flow rate was about 2 L / min.

  Table 1 shows data of the adsorption heat pump when the operation is performed under the above temperature conditions (Example 1). On the other hand, as a conventional method, the flow path configuration of the cooling water supplied from the cooling equipment 4A is changed, and is introduced so as to be introduced into the adsorption / desorption unit 1A (1B) that performs the adsorption operation first, and then circulated to the condensation unit 3. did. The conditions of cooling water, hot water, and cold water were the same as in Example 1. As a result, operation data as shown in Table 1 was obtained (Comparative Example 1). Comparing the cooling heat output between the conventional adsorption heat pump and the adsorption heat pump of the present invention, the conventional system was 232 watts, whereas the present invention obtained an output of 330 watts, confirming an output improvement of 144%. It was done.

Example 2:
The introduction flow rate of hot water to the adsorption / desorption part 1B (1A) performing the desorption operation is 4 L / min (twice that of Example 1), and the cooling water is supplied to the condensation part 3 and the adsorption / desorption part 1A (1B) performing the adsorption operation. Except for the point that the introduction flow rate was 5 L / min (1.3 times that of Example 1), the cooling output was confirmed under the same operating conditions as in Example 1, and the operation data as shown in Table 1 was obtained. (Example 2). The cold output was 440 watts, confirming a 190% improvement in output over the conventional method.

  By the way, when silica gel or other zeolite was used as the adsorbent, there was almost no change in the cooling output even when the flow path configuration of the cooling water was changed. In other words, when a specific zeolite-based adsorbent is used for the adsorbing element 1 and the cooling water is sequentially circulated to the condensing unit 3 and the adsorbing / desorbing unit 1A (1B) for performing the adsorbing operation, it is remarkably great. It was confirmed that the effect was obtained.

DESCRIPTION OF SYMBOLS 1: Adsorption element 1A: Adsorption / desorption part 1B: Adsorption / desorption part 2: Evaporation part 21: Damper 22: Damper 3: Condensing part 31: Damper 32: Damper 4A: Cooling equipment 4B: Heat source 9: Cryogenic equipment 9

Claims (5)

  An adsorption heat pump that performs heat transfer using an adsorbate adsorption / desorption function by an adsorbent, and includes at least a pair of adsorption / desorption sections each having an adsorption element that holds the adsorbent, and the adsorption / desorption sections. One of the adsorption / desorption units has an evaporating part that obtains cold heat by evaporating the adsorbate, and a condensing part that condenses and vaporizes the adsorbate vapor desorbed in each adsorption / desorption part and returns to the evaporation part. When the adsorbing operation is performed at one part and the desorbing operation is performed at the other adsorbing / desorbing part, the cooling water generated by the cooling equipment is sequentially supplied to the condensing part and one adsorbing / desorbing part and returned to the cooling equipment. And when the hot water generated by the heat source circulates to the other adsorption / desorption part, the desorption operation is performed at one adsorption / desorption part, and when the adsorption operation is performed at the other adsorption / desorption part, Cooling water generated in the cooling facility is supplied to the condensing unit and the other adsorption / desorption unit in sequence. The flow path is configured so that hot water returned to the cooling facility and generated by the heat source circulates to one of the adsorption / desorption parts, and the adsorbent held by each adsorption element is water vapor at 40 ° C. The amount of adsorption at an adsorption isotherm at a relative vapor pressure of 0.05 was 0.1 g / g or less, and the relative vapor pressure changed by 0.05 within a range of relative vapor pressure of 0.05 to 0.10. An adsorption heat pump characterized by being a zeolite having a relative vapor pressure range of sometimes 0.15 g / g or more in water adsorption amount change.   The adsorption heat pump according to claim 1, wherein the adsorption element is an element having a fin-tube heat exchanger structure. The zeolite is a zeolite in which the abundance ratio of silicon, aluminum, and phosphorus atoms is represented by the following formulas (I), (II), and (III), and is CHA in a zeolite structure defined by IZA. Adsorption heat pump described in 1.
0.001 ≦ x ≦ 0.09 (I)
(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 (II)
(In the formula, y represents the molar ratio of aluminum to the total of aluminum, phosphorus and silicon in the skeleton structure.)
0.3 ≦ z ≦ 0.6 (III)
(In the formula, z represents the molar ratio of phosphorus to the total of aluminum, phosphorus and silicon in the skeleton structure.)   Zeolite has an adsorption amount at a relative vapor pressure of 0.03 in a water vapor adsorption isotherm at 55 ° C. of 0.1 g / g or less and a relative vapor pressure in a range of relative vapor pressure of 0.03 or more and 0.20 or less. The adsorption heat pump according to any one of claims 1 to 3, wherein the adsorption amount change of water has a relative vapor pressure range of 0.15 g / g or more when the pressure changes by 0.07. The adsorption heat pump according to any one of claims 1 to 4, wherein the zeolite is a zeolite having a silicon ratio represented by the following formula (IV).
0.005 ≦ x ≦ 0.087 (IV)
(In the formula, x represents the molar ratio of silicon to the total of aluminum, phosphorus and silicon in the skeleton structure.)

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