KR20080031165A - Heat pump device - Google Patents

Abstract

The heat pump device is a configuration that occurs between the two heat exchangers because the temperature difference periodically causes expansion and compression pulsation in the working fluid vapor or gas passing through the porous solid positioned between the heat exchangers.

Description

Heat Pump Unit {HEAT PUMP DEVICE}

The present invention relates in particular to heat pump apparatus for air conditioning refrigeration and heat pump systems. This heat pump apparatus is particularly concerned with systems that do not have a fluid which is known to have a bad effect on the ozone layer in the stratosphere and have a high global warming potential for carbon dioxide. This heat pump device can immediately replace any device currently using mechanical steam recompression, or refrigeration / absorption solvent cooling, heat pump systems.

In the specification, the term 'heat pump' refers to a hydrophilic device that transfers heat from a power source to a sink that processes its energy for thermal components. Refrigerators are a special type of heat pump where low temperatures are required for certain applications. The term 'heat pump' may be used in a more limited sense than in this specification, which describes a hydrophilic device that transfers heat from a power source to a sink that processes its energy for thermal components requiring a relatively high temperature. The difference between the freezer and the heat pump, which is defined in a narrow sense, is the only intended purpose, not the principle of operation. Indeed, many air conditioning systems are designed to warm or cool according to user requirements at specific times.

Chlorofluorocarbons (CFCs, meaning CFC 11, CFC 12, later referred to as CFCs) and Hydrochlorofluorocarbons (HCFCs, HCFC 22, HCFC 123, later referred to as HCFCs) It is recognized, low toxicity and low flammability, and therefore low risk of working environment when used in refrigeration and air conditioning systems. When released into the atmosphere, they penetrate the stratosphere and attack the ozone layer, which protects the environment from damage from ultraviolet rays. The Montreal Protocol (International Environmental Contracts signed by more than 160 countries) orders that the CFCs and HCFCs be phased out in accordance with the agreed timetable.

CFCs and HCFCs have been replaced by hydrofluorocarbons (HFCs ie HFC 134a, HFC 125, HFC 32) in pure fluids or mixtures in new air conditioning, refrigeration and heat pump equipment. In order to accelerate the disposal of CFCs and HCFCs, existing devices have also been retrofitted to include appropriate HFC mixtures. Although HFCs do not reduce stratospheric ozone, HFCs are known to encourage global warming. According to the provisions of the Kyoto Protocol, all governments are obliged to limit or suspend the manufacture and release of these compounds. Some countries have already decided that the disposal of HFCs should begin sometime in the next decade, and are actively moving forward with the development of fluids that do not contain halogen.

The fluid in the device intended to replace the HFC-embedded device should be very small and preferably have no potential for global warming. Preferably, such a fluid should be a composition found in nature and its properties are understood to be such that damage to nature from emissions from humans should be avoided. Moreover, these devices are replaced with HFC embedded devices that are intended to replace them, ensuring that their damage to global warming due to emissions from fossil fuel power stations is not severe. Preferably such devices should have better energy efficiency.

Heat pump device according to the present invention;

At least one heat exchanger,

Fuselage body made of porous absorbent material and formed with inlet and outlet and arranged in thermal contact with the heat exchanger,

Means for allowing a working fluid to pass through the body,

It consists of means for creating a temperature gradient between the inlet and the outlet in the fuselage because the working fluid flows from the inlet to the outlet by causing periodic compression and expansion in the working fluid.

The present invention provides a heat pump apparatus in which a temperature difference is generated by periodically causing expansion and compression pulsation in working fluid vapor or gas passing through an absorbent porous solid installed in one or more heat exchangers.

The heat pump apparatus is arranged to dissipate heat at an elevated temperature at a first position or end of the heat exchanger and to absorb heat at a relatively low temperature at a second position or end of the heat exchanger.

In the use of this heat pump apparatus, the working fluid flows into the absorber solid at the first end under the elevated pressure and is removed by suction or at a relatively low pressure at the second end.

This heat pump apparatus also includes a heat transfer fluid.

In a specific embodiment, the heat pump apparatus consists of means for passing heat transfer fluid and heat transfer fluid in thermal contact with the heat exchanger, the means being arranged such that the flow of heat transfer fluid removes or adds heat from the heat exchanger.

Preferably the flow direction of the heat transfer fluid is changed in accordance with the compression and expansion pulsation of the working fluid.

More preferably, the flow direction of the heat transfer fluid is reversed based on the compression and expansion pulsations of the working fluid.

In a preferred specific embodiment, the flow reverse of the heat transfer fluid is synchronized with the pulsations.

The periodic kinematic frequency of the working fluid is equal to the periodic kinematic frequency of the heat transfer fluid.

The working fluid is steam, gas or fluid, preferably steam or gas. In the first part of the cycle, the heat transfer fluid moves in use from the low temperature end of the heat exchanger toward the relatively high temperature end to remove heat from the hot end of the heat exchanger to direct this heat into a suitable heat sink and release it. . In the second part of the cycle, the heat transfer fluid moves from the relatively high temperature end of the heat exchanger towards the relatively low temperature end, which is the point where it cools before entering the frozen volume. To achieve this periodic operation, the heat transfer fluid is caused to vibrate all along the heat exchanger at the same frequency as the periodic compression and expansion of the pulsating working fluid. When the working fluid is introduced into the porous solid under compression, the heat transfer fluid moves in the opposite direction to the working fluid. When the working fluid is withdrawn from the porous solid under suction, the heat transfer fluid moves in the same direction as the working fluid.

Means for generating pulses in the working fluid can be seen in volumetric compressors.

In another way the means for generating a pulse in the working fluid consists of a valve switching system and compressors. Preferably the valve switching system alternatively connects the body of absorbent material to the high and low pressure reservoirs of the working fluid.

Optionally but preferably the heat pump apparatus further comprises a heat exchanger adapted to remove compressed heat from the working fluid vapor or gas prior to contacting the absorbent body.

Pre-generated high temperatures and cooling temperatures depend on the particular application in which embodiments of the invention are used, in particular refrigeration or air conditioning. Air conditioning is understood herein as indoor cooling and warming. Heat pump devices that can provide cooling and heating according to the user's requirements are often referred to as reversible air conditioners.

Preferably, the temperature gradient is distributed at a relatively high temperature at the inlet and at a relatively low temperature at the outlet.

In another embodiment, the working fluid is a mixture of relatively strongly absorbed fluid and relatively weakly absorbed fluid. These fluids do not react strongly to each other. The relatively weakly absorbed fluid acts to remove the strongly absorbed fluid from the absorber during aspiration and carries the strongly absorbed fluid to the absorber during compression. Some examples of such compositions are carbon dioxide / nitrogen and carbon dioxide / argon combined with active porous carbon as absorbents. Specific examples of mixtures are compositions in which a relatively strongly absorbed gas, in particular ammonia or carbon dioxide, is mixed with either or both of a light gas of ammonia or helium. These light gases have high thermal conductivity compared to relatively heavy working fluid gases or vapors and improve the heat transfer that can be transferred to or received from the absorber during absorption and discharge of the relatively heavy working fluid. Compositions of helium and carbon dioxide are particularly preferred because the mixture is nonflammable.

In another embodiment of the present invention, the mixture of two or more working fluids is selected such that one fluid absorbs more strongly than the other. When the heat pump apparatus is operated under relatively light loads, the relatively strongly absorbed fluid is initially at a higher concentration in the fluid than its own concentration in the mixture entering the apparatus. In contrast, the concentration of the component that is more strongly absorbed in the mixture contained in the absorber is greater than the initial mixing concentration. When the heat pump apparatus is operated under heavy loads (high pressures), the concentration of the circulating fluid will include a fluid that is absorbed to a large extent strongly, and the composition of the circulating fluid approaches the components of the loaded mixture. By using a mixture having these properties, the heat pump apparatus is adapted to the changing load of its operation, thus maximizing its energy efficiency. An example of such a mixture is a composition of propane and carbon dioxide used with a porous carbon absorber.

The heat transfer fluid for one indoor air conditioning is generally air. In the cooling mode, the cooling temperature is typically between 5 and 15 degrees Celsius, while at high temperatures it is between about 35 and 60 degrees Celsius. Cooling power consumption is typically in the range of 3 kW to 100 kW. In the heating mode, the output temperature for the room is typically about 20 to 30 degrees Celsius. Heating power is typically about 4 kW to 150 kW. Some devices have been described as heat pump devices, which are designed for simple heating only and are used in more limited applications than those used in the specification.

Heat transfer fluids for air conditioning in large buildings with multiple rooms, such as hotels and office blocks, are water pipes that pass through each room so that air is blown over the coolant pipes to provide some cooling. Can be. This system is similar to conventional cooling installations. The temperature of the water supplied to this system is typically between 5 degrees and -10 degrees Celsius, and the water circulating in this apparatus is typically between about 0 and 15 degrees Celsius. The temperature of the water leaving this device in the heating mode is about 25 degrees to 40 degrees Celsius, while the circulating water is typically 15 degrees to 30 degrees Celsius. Cooling power consumption is usually between 50 kW and 10 MW, and these coolers can also be used in cooling condensate in process industries, for example in distillation units.

In one embodiment of the present invention, the heat pump can provide refrigeration at temperatures typically of about -30 degrees Celsius or less. In this application, it is desirable to use a relatively low freezing point heat transfer fluid. In another embodiment of the present invention, the equipment performance is optimized since the heat pumping process is performed in two or more steps. This method is particularly advantageous for temperatures below about -20 degrees Celsius. While carbon dioxide is a good refrigerant in a Lankin cycle heat pump with condenser temperatures below about zero degrees Celsius, the critical temperature is 31 degrees Celsius and the critical pressure is 72 bar. For this reason, it is not interesting to use it in heat pumps with a heating output temperature of more than 0 degrees Celsius.

A particular specific embodiment includes a warming step of a conventional Rankine cycle, wherein carbon dioxide is the working fluid and is recovered from a temperature in the range of about -55 to -10 degrees Celsius and generally at a temperature in the range of about 20 degrees to 0 degrees Celsius. This heat is allowed to enter the low temperature side of the second stage device using the present invention. The second stage device constructed in accordance with the present invention removes heat at a temperature of about 35 to 70 degrees Celsius and simultaneously operates at maximum pressure at about 10 to 30 bar of a typical current HFC based refrigeration plant.

The working fluid can be selected from chemically stable fluids that can be reversely absorbed or withdrawn from a suitable porous solid phase. Preferred fluids are carbon dioxide, air and nitrogen.

The working fluid is a fluorocarbon or a mixture of fluorocarbons boiling between -140 degrees Celsius and 40 degrees, preferably between 90 degrees Celsius and more preferably between -90 degrees and -20 degrees Celsius. CFCs, HCFCs and HFCs may be acceptable in countries where their use is permitted but are undesirable because of their adverse impact on the environment. Hydrocarbons and hydrogens can be used in applications and flammability is not a problem.

Ammonia can be accommodated in applications and exposure to humans and animals is prevented. For applications where fluorinated fluids may be preferably used, HFCs (fluoride-iodide and unsaturated fluorine compositions containing 2 to 6 carbon atoms) are preferably 150, more preferably 100 or less and more preferably 10 or less. Furnace can be used with low global warming potential for carbon dioxide (CO ₂ ). Preferred compositions are fluorine olefins. More preferred compositions are fluoro olefins including trifluorovinyl groups. Even more preferred compositions are fluoro olefins comprising at least one hydrogen atom. Particularly preferred compositions are fluoropropane and mixtures thereof. Particularly preferred working fluids where the fluorinated composition is unacceptable are carbon dioxide and nitrogen which have low environmental impact with low toxicity and low flammability.

The term 'porous solid' is used literally as a material with a wide range of properties. Many solids have a very limited porosity, including a protective oxide layer found on the metal surface. In this specification, the term 'porous solid' is used to describe a material having a particular binding property.

First, the inner surface area of the preferred porous solid is greater than about 10 m ² g ⁻¹ , more preferably greater than about 100 m ² g ⁻¹ , and more preferably greater than about 1000 m ² g ⁻¹

Secondly, the voids in a preferred porous solid are distributed in combinations of macro-, meso- and micro-pores. The porous solid consists of at least 10% of the empty volume in the form of micropores with a diameter of about 2 mm or less and at least 5% of the empty volume in the form of heavy pores having a diameter of less than about 50 nm.

Third, the preferred porous solid can reduce the pressure of the working fluid vapor or gas in contact with it and absorb the working fluid.

Fourth, the absorption process must be reversible and it must be possible to drain the working fluid because it reduces the pressure or raises the temperature of the porous solid.

Fifth, the preferred porous solid should be able to absorb the working fluid gas above the critical temperature.

A wide range of porous materials can be used. Silica, for example tanned silica or granular silica or aerogel silicas with ammonia gas, can be used including granular, monolithic and flexible blank kit aerogels.

Natural or artificial glasses, ceramics or molecular sieves can be used. Carbons that can be used consist of granular, monolithic, textile, aerogels and membranes.

Representative porous carbons suitable for the present invention are described in PCT / GBO 1/0422 and are incorporated by reference herein. Various organic materials include ezorcinol-formaldehyde foams or aerogels, other polymers in the form of polyurethane, polystyrene or foams. Inherently porous polymers in which the Taylor type micropore sizes are formed by three-dimensional linkages of suitable precursor molecular sieves (particulates) with constrained geometries are also suitable for the present invention. A range of compositions can be included, including silica-carbon compositions.

Porous materials are prepared by a sol-gel process for the production of aerogels or organic aerogels of polymeric foams and porous ceramics, silica or other minerals. For example, organic materials such as coconut and coal are thermally decomposed and then processed, for example by steam, to generate activated carbon. Polymer airgels decompose to generate carbon aerogels. Hydrocarbons are thermally decomposed to produce a carbon membrane. For example, coconut shells may be produced by plasma processes such as monomolecular sieves and carbon black or APNEP (Atmospheric Pressure Non-Equilibrium Plasma) systems developed by CTech Ltd. Carbon based materials, such as activated carbon derived from, are particularly desirable because they are obtained from substantial resources and require minimal energy input and their efficient separation of atmospheric carbon dioxide, such as carbon, in heat pump equipment for their manufacture. By the end of the operating life of the device, the carbon absorbers are removed, recovered and burned, restoring their own energy capacity initially produced when biomass is formed, returning carbon dioxide to the atmosphere. The combusted product is neutral carbon dioxide because the gas is derived from biological sources. Preferably, the carbon absorber ensures that carbon is permanently removed from the atmosphere as it is buried in landfills, tectonic plate boundaries or subterranean debris, or regenerated at an extension ratio.

Inorganic, porous materials, for example, ammonia-treated silica products from silicon tetrachloride (chloride) using oxygen-hydrogen flames are obtained by pyrolysis or plasma processes. Organic-based precursors can be pyrolyzed to produce short molecular sieves. Hydrates of natural minerals can be pyrolyzed, for example, from vermiculite and pearlite.

In one embodiment of the invention, the heat pump apparatus includes an absorbent porous mixture having properties that vary between the hot and cold ends of the absorber tube beds.

In another embodiment of the present invention, the porous solid is low enough that the self permeability of the gas to it by the gas flow occurring along the tube is such that a pressure gradient is formed along the tube during compression and aspiration. The permeability of the absorber can be suppressed in various ways. For example, a range of particle sizes can be selected depending on the length and cross-sectional area of the tube and the fluid flow rate to form a predetermined pressure gradient. Optionally, the porous solid particles are compressed into monoliths with a suitable adhesive to provide the desired pressure gradient.

Gas or vapor working fluids can be combined with the desired porous solids, for example carbon (e.g. graphite, activated carbon, charcoal, aerogels), silica (ammonia treated aerogels, alkyl group aerogels), alumina, alumino- Silicates (monomeric sieves) and organic polymers (e.g. polystyrene, polyurethane, polyacryl, polymethacryl, polyamines, polyamides, cellulose), metal sponges (e.g. nickel, titanium, iron) and metals or organics There is a metal composite or carbon supported on the polymer.

All gases and their compositions may not be suitable with these available porous solids. Although CFCs and HCFCs continue to be manufactured and used in developing countries, they are already to be disposed of under the Montreal Protocol. On many continents, chloride fluids can be used with activated carbon, silica, alumina or organic polymers, especially materials with "base" atoms such as oxygen and nitrogen or "acid" hydrogen atoms, when continued use of these chloride fluids is legitimate. . On continents where the disposal of HFCs has not been taken to date, the use of chlorides in the present invention may be acceptable, but is undesirable because their global warming potential is greater than that of the other gases described above. SO ₂ is undesirable because of toxicity.

Hydrocarbons are combined with carbon, alkyl silicas or organic polymers, especially hydrocarbon polymers such as polystyrene. Hydrocarbons more preferred than halogen fluids and SO ₂ are low inventory, hermetically sealed systems such as applications where their use can be adequately warned of their considerable flammability risks, eg large industrial applications or home refrigerators. Are limited. In addition, the disadvantage is that the enthalpy change associated with the absorption / emission of hydrocarbons is smaller than that of ionic gases, CO ₂ , SO ₂ and NH ₃ . On some continents, hydrocarbons are not preferred because they are exposed to the atmosphere and cause "photochemical smog" from exposure to sunlight.

Hydrogen is easily absorbed and released from various metal alloys, notably nickel containing alloys. Hydrogen interacts more strongly with metals than with hydrocarbons interacting with the absorbents described above. Unlike hydrogen carbon, hydrogen reacts with atmospheric hydroxyl groups, which play a major role in removing natural pollutants such as HFCs, as well as hydrogen carbon, which is released from nature. Increasing hydrogen emissions thus increase global warming.

Ammonia can be used with carbon or silica or with organic polymers. It can be used in large commercial and industrial applications where low toxicity and flammability can be controlled or in airtight, hermetically sealed home applications.

The most preferred working fluid is carbon dioxide. Although carbon dioxide obtained from fossil fuels makes the largest contribution to global warming as a single item, the amount required in the present invention is very small. The gas emitted from the heat pump apparatus of the present invention does not affect global warming at all. Carbon dioxide is easily absorbed by low toxicity, non-flammable and various kinds of porous solids, for example carbon, silica and organic polymers, especially organic polymers having basic atoms such as coral and especially nitrogen. The ability of porous solids to absorb CO ₂ can be increased by injecting these solids into combinations containing groups (stages) that can react with the fluid. Amine and amide alcohols, esters and ketones are preferred. More preferred are urethanes having a high boiling point, preferably at least 100 degrees Celsius, with amines, amides. Particularly preferred are substances having a molecular mass of N or less, preferably 100 or less and more preferably 60 or less. Particularly preferred material is polyethyleneimine.

For very low temperature freezing associated with temperatures below -55 degrees Celsius, carbon dioxide has a triple bond of -56.7 degrees Celsius. For temperatures below -55 degrees Celsius, nitrogen is preferred as the working fluid with absorbers such as activated carbon. Preferred heat transfer fluids are gases in refrigeration seals, which use air in many cases. This design provides refrigeration in the range of -130 degrees to -40 degrees Celsius and removes heat to a relatively high temperature level in the range of -55 degrees to -25 degrees Celsius.

In another embodiment of the present invention, a mixture of gases or vapors may be used if no chemical reactions occur. Thus, hydrogen carbon such as propane can be mixed with carbon dioxide.

Preferably, the temperature change generated when this fluid is absorbed and discharged back should be greater than 5 degrees Celsius, and more preferably greater than about 10 degrees Celsius.

Seven important variables are associated with temperature changes.

(a) Integrated Heat Absorption (IHA) measured between the highest and lowest pressures while the absorber is in operation

(b) heat absorption capacity (HCA)

(c) absorber density (DA)

(d) Inside surface area (SAA) of absorber

(e) Maximum working pressure (MP)

(f) absorption / discharge rate and

(g) thermal conductivity of absorber

Integrated heat absorption (IHA) is a function of the fluid's interaction with a porous solid and is defined as the total heat generated when the fluid is absorbed by the solid phase as its pressure rises from low to high pressure. The higher the IHA, the stronger the interaction with the solids in the fluid. Preferably the IHA is at least 50 KJ / kg and more preferably at least 100 KJ / kg. The most preferred IHA is expressed in KJ / mol and can be compared with the latent heat of condensation of existing refrigerants.

The larger the IHA, the lower the pressure of the fluid above the absorber. The maximum operating pressure below the heat release temperature of about 2 bar is advantageous to maintain the pressure at some point in the heat pump apparatus below the pressure controlled pressure. This makes the device cheaper to manufacture. This necessitates the use of large capacity compressors, such as centrifugal compressors, and is particularly suitable for large capacity water chillers used for air conditioning in public buildings. The IHA, which reduces the fluid pressure above the absorber pressure below 2 bar, increases the size of devices such as extruders as noted, without the economic benefits.

In heat pumps operating at a maximum operating pressure of approximately 2 bar or more, the IHA is selected to prevent the ingress of atmospheric gases, where the pressure of the absorber is less than about 1 bar at the lowest operating pressure of the device, preferably with little absorption by porous solids. do. Preferably the IHA is chosen such that the lowest operating pressure in a given application is not less than 1.5 bar.

A particular advantage of the present invention is that the temperature difference between the ends of the absorber tubes is required to produce a certain substantial temperature difference, e.g., a cold and hot air temperature of 10 degrees to 45 degrees Celsius which is usually required for air conditioning applications. By absorbing and discharging fluid to generate a relatively small temperature change of less than 5 degrees Celsius is to be induced. Despite these advantages, relatively temperature changes facilitate heat exchange between the bed and the external heat transfer fluid. Preferably the changes to absorption and emission are at least 5 degrees Celsius and more preferably at least 10 degrees Celsius. The higher the IHA, the greater the temperature change. Low absorber thermal capacity (HCA) also provides high temperature changes. Preferably the HCA is 2.00 KJ / khK or less, more preferably 1 KJ / kgK or less, and most preferably 0.8 KJ / kgK or less. Particularly preferred are metal absorbers for halogens having a porous carbon material and HCAs of 0.75 KJ / kgK or less.

Although the groups of the absorbers have similar IHAs, their ability to absorb for their working fluid may depend on the number of active sites available per unit mass. The number of active sites tends to be related to the internal area (ISA) of the porous solids that can access the fluid molecule crystals. The higher the ISA, the more desirable is the ability of a solid per unit mass to absorb fluid at a given pressure, an ISA of at least 1000 mW / g.

When IHAs, SHAs and ISAs for a series of absorbents with a particular fluid are similar, the temperature change is essentially independent of their density (DA). However, the temperature change also depends on the thermal capacity of the material from which the absorber tube is made. The amount of these materials is minimized since a porous solid with a high density is selected if it does not affect the physical properties of the other absorbents with high density discussed above. Moreover, the amount of heat transfer fluid that deprives or adds heat from the absorber tube can also determine the amount of temperature change. Low storage of heat exchange fluid is desirable.

High maximum absorption pressure maximizes the capacity of the absorber for the working fluid. However, as the pressure increases, the equal capacity of the absorber decreases and at the same time the size of the pipe required to withstand the pressure of the pipe increases with the inevitable increase in the mass of the heat exchanger and here the thermal capacity. The latter (increase in pressure) reduces the magnitude of the temperature change obtained upon absorption discharge. The optimum pressure depends on the pressure / absorption properties of the porous solid. The optimum operating pressure for the composition of CO ₂ and activated carbon is usually around 20 bar.

The thermal conductivity of the absorber is important. Particulate or granular porous solids in particular have low thermal conductivity, so that thermal conductivity during absorption and discharge limits the cycle time of the beds. In a specific embodiment the heat pumps have one or more absorber tubes which are long in comparison to their width or diameter and have been adapted for gradual heat removal or addition from one end to the other. The ratio of tube length to diameter is preferably about 5: 1 or more, more preferably about 10: 1 or more, and more preferably 20: 1.

The absorbers can be advantageously combined, in part or in whole, with the thermally conductive materials to improve the thermal conductivity of the absorber. The thermally conductive material is preferably in the form of flakes, short fibers or foams and more preferably graphite such as metal mesh, powder, wire or short fibers, preferably high thermally conductive metals such as copper and aluminum, polyaniline and polypylori Organic polymers such as tin. This thermally conductive material also has good thermal and electrical conductivity.

In a specific embodiment of the present invention, thermally conductive polymers are used that contain basic nitrogen atoms and have at least a portion of a porous solid. Such porous solids contribute to the absorption of carbon dioxide. Compressing the porous solid with monolithic gas can improve thermal conductivity. Table 1 shows various absorbent examples and their thermal conductivity. This list indicates that the thermal conductivity of the absorber is improved by adding a thermal conductive additive.

Table 1

 Absorber  Thermal Conductivity W / (m.k)    Enhancer Zeolite 13X  0.58    Enhancer Zeolite + Expanded Graphite  5-15    Fused silica  1.8    Silica gel + 20 ~ 30% expanded graphite  10-20    Monolithic Carbon  0.27-0.60    Granular Carbon  0.1    Monolithic carbon + aluminum sheet  20

Preferred absorbers have a thermal conductivity of at least about 0.5 W / (m.k), more preferably at least 5 W / (m.k), most preferably 50 W / (m.k).

The absorber heat exchange structure also affects the ease with which heat is transferred to and from the porous solid. An important requirement is to maximize heat exchange without increasing the thermal capacity of the metal components of the heat exchange so that the temperature change does not fall below the desired value of 5 degrees Celsius.

1 is a perspective view illustrating a heat exchanger assembly containing an absorbent body having an outer duct containing a heat transfer fluid;

2 is a cross-sectional view of the heat exchanger assembly shown in FIG. 1;

3 is a cross-sectional view showing multiple absorber tubes contained within a cylindrical heat transfer fluid conduit;

4 is a cross-sectional view showing multiple absorber tubes contained within a hexagonal heat transfer fluid conduit;

5A and 5B are cross-sectional views of a single absorber tube showing a longitudinal heat transfer fin and a helical heat transfer fin, respectively;

6 is a cross-sectional view illustrating an absorber pipe heat exchanger assembly having an internal heat transfer fluid tube;

7 is a cross-sectional view of the heat exchange assembly shown in FIG. 6;

8 is a cross-sectional view showing an absorber tube containing a multiple heat transfer fluid tube;

9 is a perspective view showing an obliquely wound heat absorber tube;

10 is a sectional view showing a spiral wound heat exchanger tube installed in the spiral tube;

11 is a schematic view of a first heat pump apparatus according to the present invention;

12 is a schematic view of a second heat pump apparatus according to the present invention;

13A-13F are schematic views showing, in whole or in part, a specific part of a configuration of a third heat pump apparatus according to the present invention;

14 is a schematic view of a fourth heat pump apparatus according to the present invention.

The present invention will be described in detail without reference to the accompanying drawings by way of example.

1 and 2 show a first embodiment of the present invention.

In this embodiment, the heat exchange fluid is a liquid received to flow in an outer conduit concentric with the absorber tube as shown in FIGS. 1 and 2. The heat exchange fluid conduit 1.1 houses an absorber tube. The flow of working fluid through this absorber tube is regulated by valves 1.2 and 1.3. When this absorber tube is aspirated, valve 1.6 is opened and valve 1.7 is closed. The working fluid flows outward from valve 1.6 as shown in the figure. At the same time, the heat exchange fluid flows into the conduit at valve 1.4 and outward at valve 1.5. When the heat pump apparatus is under constant pressure, valve 1.7 is closed which valve 1.6 is closed. The heat transfer fluid flows in the reverse direction, for example in valve 1.5 and outward in valve 1.4. In FIG. 2 a tube 2.4 containing an absorber 2.1, a heat transfer fluid 2.2 and a heat transfer fluid conduit 2.3 is shown. For large apparatus, multiple absorber conduits may be installed in a single fluid conduit as shown in FIGS. 3 and 4. 3 and 4 show absorbers 3.1 and 4.1, heat transfer fluids 3.2 and 4.2, heat transfer conduits 3.3 and 4.3 and heat absorber tubes 3.4 and 4.4. The conduits may have a circular, square, hexagonal or other cross section suitable for a particular application. Fins or other protrusions may be formed on the outer surfaces of the absorber tubes to increase heat transfer as shown in FIG. Longitudinal or spiral pins are preferred. In Figure 5, parts 5.1 and 5.4 are absorbers, 5.2 and 5.5 are longitudinal and spiral fins, respectively, and 5.3 and 5.6 are absorber tubes. Heat transfer from the absorber to the inner wall of the absorber is advantageously facilitated by joining the perforated metal plate, disk or other member made of short fibers or a metal mesh arranged perpendicular to the tube side in the absorbent bed. For optimal heat transfer, the heat transfer fluids should be in close contact with the inner walls.

In another embodiment of the invention, the heat transfer fluid flows through the tube in the absorber tube as shown in FIGS. 6 and 7. Part 6.1 is an absorber embedded tube. When the absorbent body is under suction as shown in FIG. 6, valve 6.2 is opened and valve 6.3 is closed so that the discharged working fluid is discharged from valve 6.6. The heat transfer fluid flows into the center tube at valve 6.4 and exits at valve 6.5. When the absorbent body is under compression, valve 6.2 is closed and valve 6.3 is open. At the same time, the heat transfer fluid flows into the tube at valve 6.5 and is output at valve 6.4. Fig. 7 shows an absorber 7.1 wrapped around a heat tube 7.3 containing a heat transfer fluid 7.2. Heat transfer between the absorber and the fluid tube can be increased by heat transfer fins perpendicular to the axis of the tube or arranged spirally along the fluid tube. Preferably these pins are tightly fitted or fixed on the outer surface of the fluid tube and are not in contact with the inner surface of the absorber tube. As shown partially cut away in FIG. 7, valve 7.3 is in contact with the heat-transferred 7.5 and valve 7.5 is perforated to allow the working fluid to pass through it. The absorbent body is contained in tube 7.4. The heat transfer fluid tube may be circular in cross section and advantageously may be compressed into an elliptical cross section to maintain the surface area but have a reduced internal volume. This geometry provides a relatively high linear velocity for the desired volumetric flow of heat transfer fluid, resulting in an improvement of the metal / fluid heat transfer coefficient.

In an embodiment according to the invention, the gas flow is suppressed to generate a pressure gradient along the absorber tube. This can be accomplished alone or in various ways or in various combinations. For example, one method is the use of an unperforated disc-shaped solid heat exchanger mounted perpendicular to the axis of the absorber and the use of fluid tubes with small gaps between their edges and the inner wall of the absorber tube embedded for the working fluid to pass through. Is related to. In the second method, the gap between the fin and the inner wall is sealed with a polymer gasket, but the fins are perforated with small holes that limit the gas flow. By varying the number of pins used, the size of the gap between the edges and / or diameters and the number of perforations, a gradient of a predetermined pressure can be achieved.

In another embodiment, a low thermally conductive liner is installed on the inner wall of the absorber tube. This structure prevents heat flow from the absorber to the wall of the absorber tube. The advantage of this structure is that the thermal capacity of the absorber receiving tube during the thermal cycle of the absorber does not significantly reduce the magnitude of the temperature change. These liners are also assembled before being inserted into their absorber tubes to act as containers for the absorbers and heat transfer fluid tubes. Another advantage of this structure is that the absorber tube, which is not required for heat transfer, can be made of materials such as stainless steel, which have stronger properties than copper or aluminum, and these metals are generally preferred when they meet high thermal conductivity. . There is also no limit to the tube wall thickness chosen to resist high pressures, independent of price and weight. It is particularly advantageous when multiple heat transfer fluid pipes are used as shown in FIG. 8. The absorber 8.1 is embedded in the tubes 8, 4 and separated from it by the insulating material 8.6. 8.2 is the heat transfer fluid enclosed in tube 8.3. The heat transfer pin 8.5, shown partially cut, increases heat transfer from the absorber to the heat transfer fluid tube. The liner is preferably assembled from a low thermal conductivity organic polymer. More preferred are open cell organic foams, such as polyurethane foams, and particularly preferred are organic foams that are externally reinforced with a solid polymer tube or surface layer to provide mechanical strength. In one embodiment of the invention, the bed receiving tube is assembled from an engineering polymer such as polyether-ether-ketone and preferably reinforced with a material such as graphite fiber. Strong compositions of this type are well known in the aviation industry and light weight construction is preferred.

In the present invention, these materials are preferred in vehicle air conditioning apparatus where small weight is required. The tube carrying the heat transfer medium is assembled from metal to facilitate heat transfer wherever possible. Preferably the tube is made of a thermally conductive metal such as copper or aluminum. Another advantage of this structure is that the tube is exposed to the external pressure of the gas rather than at the internal pressure. In this mode, copper and aluminum can be accommodated even if they are not mechanically stronger than steel.

In yet another embodiment of the present invention, the absorber tube is assembled in a helical shape and accommodated in an annular two concentric tubes forming a fluid conduit as shown in FIGS. 9 and 10. Absorbent 9.2 is contained in absorber tube 9.1. This design has particular advantages over the structure that allows the long effective length of the absorber bed to be accommodated in a substantially short actual length. In one embodiment the conduit walls are secured in close contact with the absorber tube 9.1 as shown in FIG. 10. The absorber 10.1 is wrapped in a tube 10.3 wound around the wall of the inner conduit 10.2 and sealed by the wall of the outer conduit 10.4. The heat transfer fluid is constrained to flow through the spiral passageway formed between the absorber tube and the outer and inner conduits. This structure helps to minimize the amount of heat transfer fluid in the heat exchanger and to maintain the temperature change as large as possible. It is advantageous that the water conduit can be insulated with a layer 10.5 of polystyrene or polyurethane foam or fiberglass so that the thermal gain or loss is reduced to the environment of the middle part of the heat pump apparatus.

In another embodiment of the invention, the heat transfer fluid is a gas and preferably air. This causes it to flow along the outer surface of the absorber tube. Longitudinal or helical fins are installed on the outer surface of the tube to provide good heat transfer. Heat transfer from the absorbent body to the inner wall of the absorbent material is advantageously facilitated by being made of perforated metal plates or disks or fibers of metal mesh and positioned as perpendicular to the tube as possible. The absorbers adhere to the inner wall for optimal heat transfer. The disks also act to suppress the working fluid gas flow to form a pressure gradient along the absorber tube. For example, when perforated metal tubes are used, the number, diameter and number of perforations of the metal plates are selected to form a predetermined pressure gradient.

Good heat transfer between the absorber and the heat transfer fluid is clearly preferred for optimum performance. Metal absorbers that can be used with hydrogen advantageously have higher thermal conductivity than nonmetallic materials such as carbon, zeolite and silica gel.

The choice of fluid / absorber composition depends on a number of factors with values selected to provide optimal performance for the design of a given application and absorber heat exchangers. The absorbent body is restrained in the tubes as above. The absorbent body is restrained in several sets of tubes arranged in parallel, each tubeset performing compression or suction simultaneously.

In addition, the absorbent material is restrained in several sets of tubes connected in series by pipes. When the pressure drop across the single tube is small, the actual pressure gradient is formed across the tube in series because it limits the gas flow in the connecting pipe. In another embodiment of the invention, the absorbent body is housed in a pair of plates whose edges are sealed and at both ends of which form an inlet and an outlet. The heat transfer fluid flows over the outer surfaces of the plates and thus deprives or adds heat. The structure of this mode is to have an absorption plate heat exchanger. Several sets of plate heat exchangers can be arranged in parallel and assembled into one module, allowing the heat exchange fluid to flow between each pair of heat exchangers.

In a specific embodiment of the present invention, the heat pump apparatus consists of a working fluid, a volumetric compressor driven by a mechanical power source, and a porous absorbent solids for passing pulses of the compressed working fluid. Cooling occurs because it reduces the pressure of the gas in contact with one end of the porous solid and thus absorbs the working fluid from the porous solid, while the pressure induced by the working fluid by the porous solid at the other end generates heat. Preferred working fluid / absorbent solid compositions are selected such that the absorption and discharge heats are substantially greater than the heat of compression. More preferably, the absorption and exhaust heats can be compared to the latent heat of evaporation of CFCs, HCFCs, HFCs, hydrogencarbons and ammonia currently used for conventional Rankine cycle based devices intended to be replaced.

One structure of the heat pump apparatus is shown in FIG. The compressor has a piston 11.1, which moves in the cylinder 11.2 and is driven by the piston 11.3, fixed to the crankshaft 11.4, the crankshaft 11.4 is driven by an electric motor or other prime mover, not shown. do. The compressor has two valves 11.5 and 11.6. Inlet or suction valve 11.5 is opened when the swept volume between the piston and the cylinder head is below the pressure in the heat exchanger 11.7. This occurs when the piston moves towards the bottom center. Conversely, the outlet or outlet valve 11.6 is opened when the swarf volume between the piston and the cylinder head is above the pressure in the heat exchanger 11.9. This happens when the piston moves towards top dead center. Heat exchanger 11.8 loses compressed heat to the atmosphere. The absorbent porous solid 11.10 reacts with the working fluid and reduces its pressure to a level such that the device is designed and provides resistance to its own flow, so that the pressure difference is maintained between the heat exchangers 11.7 and 11.9. The device is fully loaded with working fluid to maximize heat pumping capacity, but does not put pressure limits on this design. The device can withstand a maximum working pressure of more than 30 bar. If a low cost device is desired, the working pressure should not exceed 20 bar if possible.

The heat pump device operates in a cycle described by the following steps starting from the state where the suction stroke of the reciprocating compressor is completed.

The compression stroke is intended to start at bottom dead center, for example.

(a) The piston is driven in a cylinder to simultaneously raise the temperature and pressure of the gas working fluid until the discharge valve 11.6 is opened and the compressed gas is discharged into the heat exchanger 11.8.

(b) Heat exchanger 11.8 loses (discharges) the heat of compression to an air or water stream or other suitable sink.

(c) The cooled compressed gas enters the hot porous water exchanger 11.9 for which it is absorbed, and the absorbed heat is heated by the heat of absorption taken away by the air stream.

(d) The working fluid passes through the porous solid and moves towards the low temperature heat exchanger 11.7 under the influence of the pressure gradient set across the solid by the compressor.

(e) The working fluid dissipates heat from the porous solid in the low temperature heat exchanger 11.7, as the operating direction of the piston is reversed, thereby reducing the pressure in the cylinder to open the suction valve 11.5. The heat from this release is supplied and cooled by an external air stream.

(f) The direction of the piston is reversed again, to compress the gas and to close the suction valve.

In order for the device to operate successfully in the mode described above, at any point of the porous solid connections 11.7 and 11.9, the gas pressure vibrates around the intermediate valve, which causes the working fluid to be passed through the solid by a series of suctions and discharges by the compressor. It is important. This process will provide an important cause for enthalpy changes at porous solid junctions 11.7 and 11.9. The external air stream also vibrates along the heat exchanger in FIG. 11 to optimize the performance of this device. This vibration is generated step by step so that air flows in the same direction as carbon dioxide during the discharge of carbon dioxide (CO ₂ ) by suction from the bed. In contrast, the air flow during the aspiration of carbon dioxide is the opposite of the flow of carbon dioxide.

The reciprocating compressor shown in FIG. 11 may be replaced by any volume compressor of the rotary, sliding vane or diaphragm type. Compressors with a sliding surface in the displacement volume require an oil separator between the compressor and the suction bed to prevent oil from being lubricated by the fluid into the droplets of the bed. Therefore, oil-free compressors are preferred, for example compressors in which the moving surface in contact with the working fluid is not lubricated in the displacement volume by the fluid lubricant. Particularly preferred are diaphragm compressors that operate closer to isothermal changes than the tropics on the back, because of the considerable surface area of the compressor heads that have been increased in some units by diaphragm and oil-cooled circulating hydraulic pressure driving the diaphragm. This is due to the effective cooling of the working fluid. Diaphragm compressor energy efficiency is superior to reciprocating compressor efficiency. The fluid leakage rate is considerably low because of good sealing between the diaphragm and the compressor case, while oil-free reciprocating compressors do not have good sealing properties of the oil film of conventional reciprocating devices. Applications of relatively low duty cycles, such as domestic refrigerators, indoor air conditioning units, and diaphragm compressors, have been incorporated into conventional oil-filled hermetic reciprocating and rotating units in order to provide an excellent combination of external electric motors and gas seals. Compared with the advantages. Heat generated by the oil-filled sealed reciprocating and rotary compressors is distributed by the cooling fins. In a conventional hermetic system, motor cooling is partly by oil, where oil transfers heat to the case and refrigerant transfers heat to the condenser. The energy efficiency of the cycle can be improved by eliminating the requirement for internal cooling of the electric motor.

Various compressor designs can be used when constructed to generate pulsation of compressed gas at the hot end of the suction bed and to eliminate pulsation of the inflation gas at the cold end. 11 illustrates one way of achieving a desired design that is particularly suitable for absorbers with high thermal conductivity and good heat transfer from their volume to the external gas stream. Hydrogen / porous metal absorber conjugates are particularly suitable for this purpose. The performance of this binder can be increased by periodically including thermal breaks in the absorbent bed, for example by arranging the porous polymer plug periodically along the bed.

12 shows another embodiment of the present invention. The pressure difference is maintained by a compressor 12.3 of the type which can achieve a predetermined pressure ratio between the two vessels 12.1 and 12.2 of low and high pressure. This includes both pulsating volumetrics and continuous delivery turbo centrifugal types and is multistage if necessary. The pulsation of the compressed working fluid gas or vapor periodically closes / opens the hydraulically handed valve 12.6 and is therefore sent to the hot / high pressure heat exchanger 12.4 of the absorber bed 12.5. The pulsation of the expansion working fluid opens / closes the periodically-powered valve 12.8 and thus eliminates it from the low temperature, low pressure heat exchanger 12.7. An advantage of the design shown in FIG. 12 over the design in FIG. 11 is the ability to perform independent movement of compression and suction pulsations and to use a continuous delivery compressor. Heat exchanger 12.9 loses compressed heat to the atmosphere. The structure shown in FIG. 12 makes the cycle time of the compression / suction pulsation applied to the bed sufficiently longer than the cycle time of the volume compressor used to power this system. This design is particularly desirable when using absorbers with lower thermal conductivity than porous metals.

Porous solids, such as activated carbon, are poor heat conductors with good suction capacity for vapors and gases, but require a relatively long cycle time, e. . When the heat pump is operated in this way when used for cooling, it is only necessary to provide cooling during half of the operating cycle. This limitation is overcome in another specific embodiment of the present invention in which one bed consists of two beds of 180 ° phase so that the other bed performs compression / suction while the other bed performs suction / discharge. This embodiment using a pair of absorber tubes is shown in Figures 13A-13F. This device is intended for air conditioning of enclosed spaces, such as indoors or in a vehicle interior. Cooling air flowing into the enclosed space is usually 10 degrees Celsius to 15 degrees Celsius, and air exhausted to the outside environment is usually 35 to 65 degrees Celsius. Absorbents contained in the two finned tubes 13.1 and 13.2 are enclosed in the two air conduits 13.12 and 13.13 shown in FIG. 13B. Air is transported through the conduits by fans 13.5 and 13.9. Fan 13.9 draws exhaust air from the air-conditioned room while fan 13.5 draws outside air. The flow by the two fans actuates the actuating valve vanes 13.14 and 13.15 shown in FIG. 13C so that they are periodically replaced simultaneously between conduits 13.12 and 13.13. In this replacement, the outside air flow from the vane fan 13.5 is blown into the conduit 13.13, and at the same time the vented indoor air is directed through the conduit 13.12. The dotted line indicates another position of the vane.

The working fluid is compressed by compressor 13.6 which is driven by motor 13.16. The flow of working fluid through this device is such that pressure equalizing valve 13.3 and switching valve 13.7 acting to periodically switch the working fluid between the two finned tubes 13.1 and 13.2 while keeping the other under compression while one is under suction. Adjusted by 13.8. Compressed heat is removed by heat exchanger 13.16 where air is sent out by fan 13.11. 13D, 13E and 13F show a design with a plurality of suction tubes arranged in two sets, illustrating the operation applied to an indoor air conditioning apparatus. The working fluid flows around the circuit by the compressor 13.6. In order to increase heat transfer, each bed consists of a number of parallel tubes filled with absorbers to maximize the surface area exposed to the air stream. The operating cycle is for lifting purposes only and not for limiting purposes. This operation starts at the point shown in FIG. 1D at room exhaust temperature and is filled with working fluids absorbed at maximum operating pressure, for example, 20 degrees Celsius. Finned tube 13.2 is at ambient ambient air temperature and is filled with working fluid absorbed at the minimum pressure of the system, such as 30 degrees Celsius.

a. There is no air flow over either bed, the compressor is switched off and valve 13.3 is opened with the valves 13.7 and 13.8 closed, allowing the working fluid to flow from the finned tube 13.1 to the finned tube 13.2. The working fluid also allows the passage of a condenser or another engine to equalize the pressure, the advantage of which is that useful work is done from the compressor or engine. In the final adiabatic process, the temperature of the finned tube 13.1 drops below the exhaust temperature. Conversely, the temperature in finned tube 13.2 rises above the ambient ambient temperature as the fluid is absorbed.

b. When the pressure is in equilibrium, valve 13.3 is closed. Valves 13.7 and 13.8 are open and compressor 13.6 pumps working fluid from finned tube 13.1 (outlet) to finned tube 13.2 (suction) at the switching temperature. The ambient external air, driven by fan 13.5 and flowing over finned tube 13.1, is thus cooled and introduced into the room at a predetermined low temperature, for example 10 degrees Celsius. On the contrary, the same volume of exhaust air is removed from the room by the fan 13.9, heated to a temperature higher than the temperature of the surrounding ambient air, and flows over the fin tube 13.2, and the heat is lost to the atmosphere.

c. Because the finned tubes 13.1 and 13.2 are designed to have substantially greater lengths than their diameters, the temperature of the air stream exiting the heat exchanger containing the absorber, respectively, is such that the finned tubes 13.1 are heated up to the ambient air temperature along their length. It is approximately constant until the finned tube 13.2 cools to the temperature of the exhaust air.

d. Upon reaching this point, the device is in a state similar to the initial state (a), but with finned tube 13.1 at low pressure and ambient temperature and with finned tube 13.2 at high pressure and exhaust temperature. In other words, the finned tubes 13.1 and 13.2 changed their roles.

e. The cycle operation continues as described in (a) to (c) above until the device returns to the initial state. To achieve this final step, vanes 13.14 and 13.15 are switched to reverse air flow through conduits 13.2 and 13.2 as shown in FIG. 13F. At the same time valves 13.7 and 13.8 are reset to cause the compressor to transfer the working fluid from the finned tube 13.2 to the finned tube 13.1.

In another specific embodiment of the apparatus, one or more paired absorber heat exchangers are used to keep the working fluid between two groups of second paired heat exchangers when the pressure is balanced in a pair of heat exchange periods. To move it. This arrangement has the advantage of providing effective and continuous heat pumping.

In another embodiment of the invention, the absorber beds are cooled and heated by the circulating fluid. 14 illustrates a possible design for this device.

The circuit of absorber tubes 14.1 and 14.2 containing internal heat transfer tubes is connected to the compressor 14.7, the pressure balance valve 14.11, the flow switching valves 14.3 and 14.4 and the heat exchanger 14.12 to remove the heat of compression. The fluid circuit consists of eight fluid logic diodes arranged in two bridge rectifiers 14.5 and 14.6, a fluid pump 14.10 and two heat exchangers 14.8 and 14.9 and 14.9 with inlet and outlet stages allowing the flow to be reversibly periodically. Pass in the same direction and at the same time allow the fluid to vibrate in the absorber heat exchanger. The heat transfer fluid circuit is shown by the gothic line in FIG. 14. The cycle operation used is essentially the same as the operation described for the device in FIGS. 13D, 13E and 13F. The working fluid is discharged from one bed by the operation of compressor 14.7 and compressed and transferred to another bed. The dotted line represents the working fluid circuit. In one embodiment of the invention, the fluid passes through one or more tubes or pipes within the absorbent bed. The fluid also flows through conduits external to the absorber receiving tube. The apparatus shown in FIG. 14 is suitable for a water cooling air air conditioning system in which a substantial portion of the refrigeration enclosure and air are recycled indoors or in buildings.

Suitable heat transfer fluids require a combination with properties determined by the desired application. Air is an attractive choice for air conditioning. When fluids are used the fluids should have a low viscosity to minimize pumping energy whenever possible. Preferably the fluids have a mechanical viscosity of 0.025 waves or less, more preferably 0.01 waves or less, and particularly preferably 0.001 or less. When the fluid circulation system is properly pressurized a fluid having a range of boiling points can be considered. Preferably for ease of operation the fluid should have a normal boiling point that is greater than the highest temperature reached by the absorbent body. The fluid should not freeze below the lowest temperatures generated in this device. Preferably the fluid has a flash point of at least 100 degrees Celsius, more preferably at least 130 degrees Celsius, and even more preferably at least 200 degrees Celsius. Most preferably the fluid should be nonflammable. Preferred fluids include those fluids known in the industry as the second refrigerant. These materials consist of water, saline, glycols, alcohols, hydrocarbon oils, halogenated compositions including silicon oils and partially fluorinated ethers, fluorinated ethers and chlorinated fluids. These fluids are used in mixtures if they are compatible with each other.

Compositions in a wide range of fluids are used for low freezing temperatures below -50 degrees Celsius and at the same time these compositions have the desirable properties of flash points above 100 degrees Celsius and typical boiling points greater than the highest temperature. Preferred materials consist of esters and ethers comprising three or more carbon atoms which may be acrylic (composition) or cyclic (composition). Preferred materials are not limited to this, but glycol- or polyol-cyclic ones are propylene carbonate, ethylene carbonate and dimethyl isosorbides. Esters, ethers, glycols may be used in which mixtures are mixed with one another or with water. Fluids optionally include additives that enhance one or more desired compositional properties such as relatively low freezing point, relatively high boiling point, relatively low viscosity or high flash point. Such additives are undesirable when used alone but may be acceptable when used in mixtures of up to 50% by mass.

In order to avoid adverse environmental impacts containing fluorine or chlorides, these compositions have reactions such as double or triple bands, which have as low vapor pressure as possible or facilitate the rapid destruction by reactants (species) in the atmosphere. It must be combined with groups.

Claims (49)

In the heat pump apparatus, At least one heat exchanger; A body having an inlet and an outlet and made of a porous absorber material and installed in thermal contact with the heat exchanger; Means for causing the working fluid to pass through the fuselage; And a means for generating periodic compression and expansion pulsations in the automatic fluid, thereby causing a working fluid to flow from the inlet to the outlet, thereby forming a temperature gradient in the fuselage between the inlet and the outlet. The method of claim 1, And means for thermally contacting the heat transfer fluid and the heat exchanger to allow the flow of heat transfer fluid to remove or add heat from the heat exchanger. The method of claim 2, A heat pump apparatus characterized in that the flow direction of the heat transfer fluid is changed according to the compression and expansion pulsation of the working fluid. The method of claim 3, A heat pump apparatus characterized in that the flow direction of the heat transfer fluid is simultaneously reversed in accordance with the compression and expansion of the working fluid. The method of claim 4, wherein Heat pump device, characterized in that the reverse of the flow direction of the heat transfer fluid is synchronized with the pulsation. The method according to any one of claims 3 to 5, And a periodic operating frequency of the working fluid is equal to the periodic operating frequency of the heat transfer fluid. In any preceding claim, And a means for causing pulsation in the working fluid is a volumetric compressor. The method according to any one of claims 1 to 6, And a means for causing pulsation in the working fluid comprising a valve switching system and a compressor. The method of claim 8, And a valve switching system alternately connects the fuselage of the absorber material and the low pressure reservoir of the working fluid. In any preceding claim, And another heat exchanger adapted to remove compressed heat from the working fluid prior to contacting the absorber material. In any preceding claim, A heat pump apparatus, characterized in that the temperature gradient is formed at a relatively high temperature at the inlet and a relatively low temperature at the outlet. In any preceding claim, Wherein the working fluid is selected from a stage consisting of steam or gas or mixtures thereof. In any preceding claim, Heat pump device, characterized in that composed of a plurality of heat exchangers. The method according to any one of claims 1 to 13, Heat pump device characterized in that the working fluid is a single fluorocarbon or a mixture of fluorocarbons boiling between -140 degrees Celsius and 40 degrees Celsius. The method of claim 14, A heat pump device characterized in that the boiling point of the working fluid is between -90 degrees Celsius and 0 degrees Celsius. The method of claim 15, A heat pump device characterized in that the boiling point of the working fluid is between -90 degrees Celsius and -20 degrees Celsius. The method according to any one of claims 1 to 3, Wherein the working fluid is selected from a stage consisting of methane, ethane, propane, iso-butane and butanes and mixtures thereof. The method according to any one of claims 1 to 1, Heat pump device, characterized in that the working fluid is nitrogen. The method according to any one of claims 1 to 13, A heat pump apparatus, characterized in that the working fluid is carbon dioxide. The method according to any one of claims 1 to 13, A heat pump apparatus, characterized in that the working fluid is hydrogen. The method according to any one of claims 1 to 13, Heat pump apparatus characterized in that the working fluid is rare gas In any preceding claim, A heat pump apparatus characterized in that the porous solid has a small volume of 2 nm or less in diameter and has a volume of at least 10%. The method of claim 22, A heat pump apparatus characterized in that the porous solid has a hollow volume of at least 10% in the form of a medium hole having a diameter of 50 nm or less. The method of claim 23, wherein A heat pump apparatus characterized in that a porous solid has a void volume of 20% in the form of a large hole having a diameter larger than 50 nm. In any preceding claim, A heat pump apparatus characterized in that the absorbent porous solid is made of carbon-based material. The method of claim 25, Heat pump device, characterized in that the absorbent porous solid is a charcoal (charcoal) material. The method of claim 26, Heat pump device, characterized in that the absorbent porous solid is an active carbon material. The method of claim 25, Heat pump apparatus, characterized in that the absorbent porous solid is an organic polymer based material. The method of claim 25, Heat pump apparatus, characterized in that the absorbent porous solid is a materially non-organic material. The method of claim 29, A heat pump apparatus characterized in that the absorbent porous solid is made of a metal or nonmetal oxide or a composition thereof. The method of claim 29, Heat absorber device characterized in that the absorbent porous solid is zeolite. The method of claim 29, Heat pump device, characterized in that the absorbent porous solid is a sieve. The method of claim 29, And an absorbent porous solid is selected from the group consisting of silica, alumina, titanium dioxide and mixtures thereof. The method according to any one of claims 1 to 21, Heat pump apparatus, characterized in that the absorbent porous solid is an aerogel. In any preceding claim, Heat absorber device characterized in that the low viscosity solvent is injected into the absorbent porous solid. In any preceding claim, Heat absorber device characterized in that the absorbent porous solid comprises an additive to increase the thermal conductivity. In any preceding claim, A heat pump apparatus, characterized in that the enthalpy of absorption and discharge in the heat exchanger is essentially the same. In any preceding claim, Heat pump device, characterized in that the pulsations have a period ranging from 1 second to 10 seconds. The method of claim 36, A heat pump apparatus, characterized in that this period is in the range of 1 to 30 seconds. The method of claim 39, A heat pump apparatus characterized in that this period is in the range of 1 second to 10 seconds. In any preceding claim, And a pressure gradient of the working fluid is formed between the inlet and the outlet. In any preceding claim, A heat pump apparatus, characterized in that the working fluid is a mixture. The method of claim 42, wherein And wherein the working fluid is a mixture of a strongly absorbed fluid and a weakly absorbed fluid. The method of claim 42 or 43, wherein And a working fluid is a mixture of carbon dioxide and nitrogen. The method of claim 42 or 43, wherein A heat pump apparatus, characterized in that the working fluid is a mixture of carbon dioxide and argon. The method of claim 42 or 43, wherein And the working fluid is carbon dioxide or a mixture of ammonia and hydrogen, helium or mixtures thereof. The method of claim 42 or 43, wherein And the working fluid is a mixture of carbon dioxide and propane. In the heat pump apparatus, And a temperature difference between the two heat exchangers, as the temperature difference causes periodic expansion and compression in the working fluid vapor or gas passing through the absorbent porous solid located between the heat exchangers. The method of claim 39, A heat pump apparatus, characterized in that the temperature difference is essentially constant between each heat exchanger and an external single-phase heat transfer fluid.

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