ES2694643A1 - METHOD TO REGENERATE A DESICCANT, AND COMPONENT OF DOMESTIC APPLIANCES AND DOMESTIC APPLIANCES WITH MEANS TO REGENERATE A DESIRE (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

The present invention relates to a method for releasing a fluid, which is absorbed by a desiccant (2), from said desiccant (2). The method comprises the steps of placing the desiccant (2) comprising the fluid absorbed in contact with a carrier (1), where the carrier (1) comprises openings and has a thermal conductivity λ of at least 10W/(m* K) at 0ºC, heating the carrier (1) to a predetermined temperature, and releasing at least part of the desiccant fluid (2) by transferring thermal energy from the carrier (1) to the desiccant (2). Also, the invention refers to a domestic appliance component and a domestic appliance comprising at least one component of domestic appliance.

Description

The present invention relates to a method for releasing a fluid, which is absorbed by a desiccant, from said desiccant. In addition, the present invention relates to a domestic appliance component and a domestic appliance with means for regenerating a desiccant.

Desiccants are used to a large extent for various purposes thanks to their ability to

10 adsorb and / or absorb water and other fluids. In most applications, desiccants induce dryness in the environment and reduce the amount of moisture present. In other applications, desiccants are used to accelerate the phase transition of water from liquid to vapor. Some desiccants are chemically inert, while others are reactive and require specialized techniques for handling. The most desiccant

15 common is silica, an inert white solid, non-toxic, and insoluble in water. Once the desiccant is saturated, the adsorption / absorption process must be inverted by desorbing the desiccant fluid, in order to prepare the desiccant for its next work cycle.

The usual form of desorption of the fluid absorbed from the desiccant, a process called

"Regeneration" is usually carried out by heating the desiccants to certain temperatures by applying heat with infrared heat sources (radiation) or by applying a purge gas stream. However, these methods require a considerable amount of time to remove the volume of fluid adsorbed from the desiccant.

The present invention solves the technical problem of providing a method for releasing a fluid, which is absorbed by a desiccant, from said desiccant, more quickly and efficiently. Another technical problem solved by the present invention is to provide a domestic appliance component that can regenerate a desiccant more quickly and efficiently. Also, the present invention solves the technical problem of

30 providing a domestic appliance comprising at least one component of domestic appliance, which can regenerate a desiccant more quickly and efficiently.

These problems are solved by a method, a household appliance component, and a household appliance according to the independent claims. In the respective dependent claims, advantageous developments of the invention are specified, where advantageous developments of a specific aspect of the invention are to be considered advantageous developments of all other aspects of the invention, and vice versa.

The first aspect of the invention refers to a method for releasing a fluid, which is absorbed by a desiccant, from said desiccant. A faster and efficient way to regenerate said desiccant is achieved by the steps of placing the desiccant comprising the absorbed fluid in contact with a carrier, where the carrier comprises openings and has a thermal conductivity λ of at least 10 W / (m * K) at 0 ° C, heating the carrier to a predetermined temperature, and releasing at least some of the fluid from the desiccant by transferring thermal energy from the carrier to the desiccant. The predetermined temperature depends on the properties of the specific desiccant. As already stated, the way of desorbing fluid from a desiccant according to the prior art is by heating it, since the desorption (regeneration) is favored at high temperatures. However, this process is slow and inefficient, since radiation or convection is used to heat the desiccant. Thus, according to the prior art, the air surrounding the desiccant is first heated. Afterwards, heat is transferred slowly from the air to the desiccant thanks to the low thermal conductivity of the air. However, the air has only a thermal conductivity λ of about 0.0262 W / (m * K) at 0 ° C. In contrast to this, according to the method of the present invention, the desiccant is contacted with a carrier which is made of a material with a high thermal conductivity λ of at least 10 W / (m * K) (measured at 0 ° C). The thermal conductivity λ of at least 10 W / (m * K) comprises, for example, λ values of 10 W / (m * K), 20 W / (m * K), 30 W / (m * K), 40 W / (m * K), 50 W / (m * K), 60 W / (m * K), 70 W / (m * K), 80 W / (m * K), 90 W / (m * K), 100 W / (m * K), 110 W / (m * K), 120 W / (m * K), 130 W / (m * K), 140 W / (m * K), 150 W / (m * K), 160 W / (m * K), 170 W / (m * K), 180 W / (m * K), 190 W / (m * K), 200 W / (m * K), 210 W / (m * K), 220 W / (m * K), 230 W / (m * K), 240 W / (m * K), 250 W / (m * K), 260 W / (m * K), 270 W / (m * K), 280 W / (m * K), 290 W / (m * K), 300 W / (m * K), 310 W / (m * K ), 320 W / (m * K), 330 W / (m * K), 340 W / (m * K), 350 W / (m * K), 360 W / (m * K), 370 W / (m * K), 380 W / (m * K), 390 W / (m * K), 400 W / (m * K), 410 W / (m * K), 420 W / (m * K) or more (measured at 0 ° C). Thus, by using said carrier, heat is transferred to the desiccant by conduction and, therefore, much more quickly than in conventional heating modes (radiation or convection), since the carrier has a thermal conductivity λ much more elevated and is in direct contact with the desiccant. Consequently, the carrier and the desiccant are heated faster, so that

the fluid, for example, water, which has been captured or adsorbed / absorbed (chemical adsorption) by the desiccant, is rapidly desorbed and can exit the carrier through the openings, resulting in a regeneration of the desiccant quickly and efficiently .

According to an advantageous development of the invention, the desiccant comprising the absorbed fluid is embedded in a carrier having a mesh and / or foam geometry and / or the desiccant comprising the absorbed fluid is disposed on a storage area of the carrier with a rough surface structure and / or the carrier defines a chamber containing desiccant, in which the desiccant is disposed. This makes possible the homogenous distribution of the desiccant within and / or on the carrier, the direct contact between the desiccant and the carrier and, therefore, a particularly rapid transfer of heat and regeneration of the desiccant. The design of the carrier, for example, a mesh or foam structure, may be chosen based on the heating method to be used and on the size and shape of the desiccant. By way of example, the carrier can have a three-dimensional structure made of two or more mesh layers arranged one above the other, or it can be a porous foam in which the desiccant particles are distributed homogeneously. Additionally or alternatively, the carrier can be a plate (horizontal) with a rough surface on which the desiccant particles are distributed in order to increase the contact surface with the carrier and, thus, the heat transfer coefficient . Also, the bearer can define a chamber containing desiccant, in which the desiccant is disposed. The carrier can be, for example, a tubular mesh that is filled with the desiccant.

In another advantageous development of the invention, the carrier is heated to said predetermined temperature by one or more of between induction heating, electric heating, and radiant heating. Thus, the method is easily adaptable to different heating devices and, therefore, can be used in different household appliances.

In another advantageous development of the invention, it is provided that a gas is passed through the openings of the carrier to remove at least part of the fluid released from the desiccant. This step accelerates the regeneration of the desiccant, since the desorbed fluid is entrained by the gas from the desiccant and can not be readsorbed / reabsorbed by the desiccant. This step can also be used to remove essentially the entire volume of absorbed fluid from the desiccant, in order to achieve complete regeneration.

In another advantageous development of the invention, it is provided that the carrier is composed of a metal, in particular aluminum and / or copper, or a metal alloy, in particular, an alloy of steel and / or aluminum. Metals and / or metal alloys such as, for example, steel or aluminum, are inexpensive and have good values of thermal conductivity λ of at least 15 W / (m * K). Also, metals and metal alloys can be easily heated by the application of an electric current, that is, the carrier is used as a heating resistor. This is a simple, quick and economical method to heat the carrier and, therefore, the desiccant.

The second aspect of the invention refers to a domestic appliance component, which comprises a carrier, which is in contact with a desiccant to absorb fluid, where the carrier comprises openings and has a thermal conductivity λ of at least 10 W / ( m * K) at 0 ° C, and a heating device, which is configured to heat the carrier to a predetermined temperature such that at least part of the fluid that has been absorbed by the desiccant is released from the desiccant by transferring thermal energy from the desiccant. carrier to the desiccant. Expressed in another way, the domestic appliance component according to the present invention comprises a desiccant, which is in contact with a carrier. The carrier is made of a material with a high λ thermal conductivity of at least 10 W / (m * K) (measured at 0 ° C). The thermal conductivity λ of at least 10 W / (m * K) comprises, for example, λ values of 10 W / (m * K), 20 W / (m * K), 30 W / (m * K), 40 W / (m * K), 50 W / (m * K), 60 W / (m * K), 70 W / (m * K), 80 W / (m * K), 90 W / (m * K), 100 W / (m * K), 110 W / (m * K), 120 W / (m * K), 130 W / (m * K), 140 W / (m * K), 150 W / (m * K), 160 W / (m * K), 170 W / (m * K), 180 W / (m * K), 190 W / (m * K), 200 W / (m * K), 210 W / (m * K), 220 W / (m * K), 230 W / (m * K), 240 W / (m * K), 250 W / (m * K), 260 W / (m * K), 270 W / (m * K), 280 W / (m * K), 290 W / (m * K), 300 W / (m * K), 310 W / (m * K ), 320 W / (m * K), 330 W / (m * K), 340 W / (m * K), 350 W / (m * K), 360 W / (m * K), 370 W / (m * K), 380 W / (m * K), 390 W / (m * K), 400 W / (m * K), 410 W / (m * K), 420 W / (m * K) or more (measured at 0 ° C). Said carrier can be heated through a heating device in such a way that heat is transferred by conduction of the carrier to the desiccant. Therefore, the heat transfer is much faster than in conventional heating modes (radiation or convection), since the carrier has a much higher thermal conductivity λ and is in direct contact with the desiccant. Accordingly, the carrier and the desiccant can be heated more rapidly, so that the fluid, eg, water, which has been captured or adsorbed / absorbed (chemical adsorption) by the desiccant, can be desorbed rapidly and can exit the carrier through the openings, resulting in a fast and energy efficient regeneration of the desiccant.

In an advantageous embodiment of the invention, it is provided that the carrier comprises one or more of the group consisting of two or more mesh layers, between which at least part of the desiccant is disposed, a foam, in which it is disposed at less part of the desiccant, a storage area with a rough surface structure, on which at least part of the desiccant is disposed, and a chamber containing desiccant defined by the carrier, in which the desiccant is disposed. Thus, the domestic appliance component can be easily adapted to different applications and domestic appliances provided.

In another advantageous embodiment of the invention, it is provided that the domestic appliance component further comprises a fan device for passing a gas through the openings of the carrier to remove at least part of the fluid released from the desiccant. The use of a fan device accelerates the regeneration of the desiccant, since the desorbed fluid can be entrained by the gas from the desiccant and can not be readsorbed / reabsorbed by the desiccant. The fan device can also be used to remove essentially the entire volume of absorbed fluid from the desiccant, in order to achieve complete regeneration.

In another advantageous embodiment of the invention, it is provided that the carrier is composed of a metal, in particular aluminum and / or copper, or a metal alloy, in particular, an alloy of steel and / or aluminum. Metals and / or metal alloys such as, for example, steel or aluminum, are inexpensive and have good values of thermal conductivity λ of at least 15 W / (m * K). Also, metals and metal alloys can be easily heated by the application of an electric current, that is, the carrier is used as a heating resistor. This is a simple, quick and economical method to heat the carrier and, therefore, the desiccant.

In another advantageous embodiment of the invention, it is provided that the heating device is configured to heat the carrier to said predetermined temperature by one or more of between induction heating, electric heating, and radiant heating. Thus, the heating device is easily adaptable to various domestic appliances.

In another advantageous embodiment of the invention, it is provided that the desiccant is chemically inert. This ensures great stability and an extended shelf life of the desiccant. The desiccant can be or comprise, for example, silica, silica gel and / or one or more zeolites.

The third aspect of the invention refers to a domestic appliance, which is configured to carry out a method according to the first aspect of the invention and / or which comprises at least one component of domestic appliance according to the second aspect of the invention . The resulting features and their advantages can be extracted from the description of the first and second aspects of the invention.

In an advantageous embodiment of the invention, it is provided that the domestic appliance is configured as a dishwashing machine, as a dryer, as a washing machine, as a microwave oven, and / or as a steam oven. All these embodiments are exposed to moisture, so they need a fast and energy efficient way to reactivate the desiccant used to reduce humidity.

In another advantageous embodiment of the invention, it is provided that the household appliance further comprises a control device, which is configured to generate control signals for directing the heating device. This allows a particularly precise control of the desiccant reactivation.

In another advantageous embodiment of the invention, it is provided that the control device is configured to generate the control signals based on the state relative to the load of the desiccant with fluid. In this way, it is ensured that only a cycle of reactivation of the desiccant is initiated if necessary as a consequence of the state relative to the load thereof. Thus, it is safely avoided that energy is wasted unnecessarily.

Other characteristics of the invention are taken from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description, as well as the characteristics and combinations of features mentioned below in the description of the figures and / or shown alone in the figures are usable not only in the combination indicated in each case, but also in other combinations, without leaving the scope of the invention. Therefore, it should be understood that those embodiments are also comprised and disclosed by the invention that are not explicitly shown in the figures and are not explained, but can be extracted through combinations of features separated from the exposed implementations, and that can be generated from these. Accordingly, those embodiments and combinations of characteristics that do not have all the characteristics of an independent claim originally formulated will also be considered disclosed. Likewise, those forms of realization and combinations of characteristics that transcend or that differ from those described above will be considered disclosed by means of the embodiments set forth above.

combinations of features set forth in references to the claims. The figures show in:

Fig. 1

a schematic sectional view of a carrier, which is configured as metallic foam and in which a desiccant is disposed;

Fig. 2

a schematic sectional view of the carrier, which is configured as a metal mesh and on which the desiccant is disposed; Y

Fig. 3

a perspective view of several carriers, which are configured as metallic tubular meshes.

Figure 1 shows a schematic sectional view of a carrier 1, which is configured as metallic foam and in which a desiccant 2 is disposed. The desiccant 2 is composed of particles, which are distributed homogeneously inside the carrier 1. The Carrier material 1 can, for example, comprise or be composed of steel or aluminum, which are economical materials with good thermal conductivity. Thus, carrier 1 has a high thermal conductivity λ of at least 15 W / (m * K) (measured at 0 ° C) and a low specific thermal capacity. The desiccant 2 can, for example, comprise or be composed of zeolites. In addition, the carrier 1 is connected to an electric heating device 3, which is configured to heat the carrier 1 to a predetermined temperature such that at least part of a fluid that has been absorbed by the desiccant 2 is released from the desiccant 2 by transferring thermal energy from the carrier 1 to the desiccant 2. Therefore, the carrier 1 can be heated rapidly, so that the temperature of the desiccant 2 increases, which results in the desorption of the fluid absorbed. The fluid may be, for example, water, a solvent, or other types of fluids. Then, the desorbed fluid can exit the carrier 1 through the porous holes of the foam. Expressed in another way, the metal foam of carrier 1 is heated by an electric current comparable to a resistor. This is a simple, quick and economical method to heat the metallic carrier 1. The heat is transferred from carrier 1 to desiccant 2 much more quickly than in conventional heating methods, since carrier 1 is in direct contact with desiccant 2. Thus, heat is transferred by conduction (more rapidly) in place by radiation or convection (more slowly), which leads to a rapid and efficient regeneration of the desiccant 2. This principle can be used, for example, in household appliances, in particular in household appliances that use water.

Figure 2 shows a schematic sectional view of another embodiment of the carrier 1, which is configured as a metal mesh and on which the desiccant 2 is disposed. The carrier 1 may comprise two or more layers of mesh to surround the desiccant particles 2. The carrier 1 is again in functional connection with an electric heating device 3.

Figure 3 shows a perspective view of several carriers 1, which are configured as metallic tubular meshes of different sizes. Thus, each carrier 1 defines a chamber containing desiccant 4. Thus, desiccant 2 (eg, zeolites) can be easily disposed within the chamber containing desiccant 4 of each metal tubular mesh and be replenished if necessary. In addition, a stream of air or gas can easily be supplied to the carrier 1. With this configuration, the air / gas can be in contact with a large percentage of the surface of the desiccant 2 and remove the desorbed fluid from the desiccant 2.

Apart from these three-dimensional mesh or foam structures, it is also possible in general to configure the carrier 1 as a horizontal plate with a (slightly) rough surface on which the desiccant particles 2 are homogeneously distributed, in order to increase the contact surface with the heatable structure of the carrier

one.

The advantages of all the embodiments of the present invention comprise the following points:

-

the transfer of heat between the heat source (heating device 3) and the desiccant 2 is much faster compared to, for example, the methods of radiation heating, thanks to the heat-conducting carrier 1. Therefore, heat transfer is carried out by conduction, and not by convection or radiation;

-

the principle of the present invention is easily adaptable to different heating methods and heating devices 3 (radiation / convection, induction heating, electric / conduction heating);

-

the principle of the present invention is particularly energy efficient, since the thermal energy is transferred directly to the desiccant 2 and less waste is generated; Y

-

by using a porous carrier 1, such as foams and / or a carrier with many openings such as meshes (tubular), air or other gases can be

contact with a large percentage of the surface of the desiccant 2 (zeolites), thus improving the processes of adsorption and regeneration.

Those skilled in the art will understand that, while the present invention has been disclosed by reference to the preferred embodiments, may be made 5 various modifications, changes and additions to the previous invention without abandoning the spirit and the scope of it. The values of the parameters used in the claims and in the description to define the conditions of the process and measurement to characterize the specific properties of the invention are also included within the framework of deviations, for example, as a result of measurement errors,

10 system errors, weight errors, DIN tolerances, and the like.

REFERENCE SYMBOLS

one

Carrier

two

Desiccant

3

Heating device

4

Chamber containing desiccant

Claims (13)

A method for releasing a fluid, which is absorbed by a desiccant (2), from said desiccant (2), which comprises the steps of:

-

putting the desiccant (2) comprising the fluid absorbed in contact with a

5 carrier (1), where the carrier (1) comprises openings and has a conductivity thermal λ of at least 10 W / (m * K) at 0 ° C;

-

heating the carrier (1) to a predetermined temperature; Y

-

releasing at least part of the fluid from the desiccant (2) transferring thermal energy from the carrier (1) to the desiccant (2).

The method according to claim 1, wherein the desiccant (2) comprising the absorbed fluid is embedded in a carrier (1) having a mesh and / or foam geometry and / or where the desiccant (2) comprising the absorbed fluid is disposed on a storage area of the carrier (1) with a surface structure 15 and / or where the carrier (1) defines a chamber containing desiccant (4), in which the desiccant (2) is disposed. 3. Method according to claim 1 or 2, wherein the carrier (1) is heated to said predetermined temperature by one or more of between induction heating, electric heating, and radiant heating. 4. Method according to any of claims 1 to 3, wherein a gas is passed through the openings of the carrier (1) to remove at least part of the fluid released from the desiccant (2). Method according to any of claims 1 to 4, wherein the carrier (1) is composed of a metal, in particular, aluminum and / or copper, or a metal alloy, in particular, a steel alloy and / or aluminum. 6. Domestic appliance component, which comprises

-

a carrier (1), which is in contact with a desiccant (2) to absorb fluid, where the carrier (1) comprises openings and has a thermal conductivity λ of at least 10 W / (m * K) at 0 ° C; Y

-

a heating device (3), which is configured to heat the carrier (1) to a predetermined temperature such that at least part of the fluid

which has been absorbed by the desiccant (2) is released from the desiccant (2) by transferring thermal energy from the carrier (1) to the desiccant (2). 7. Domestic appliance component according to claim 6, wherein the carrier (1) 5 comprises one or more of

-

two or more mesh layers, between which at least part of the desiccant (2) is disposed;

-

a foam, in which at least part of the desiccant (2) is disposed;

-

a storage area with a rough surface structure, on which at least part of the desiccant (2) is disposed; Y

-

a chamber containing desiccant (4) defined by the carrier (1), in which the desiccant (2) is disposed.

8. Domestic appliance component according to claim 6 or 7, and which 15 further comprises a fan device for passing a gas through the openings of the carrier (1) to remove at least part of the fluid released from the desiccant (2). Domestic appliance component according to any of claims 6 to 8, wherein the carrier (1) is composed of a metal, in particular, aluminum and / or copper, or a metal alloy, in particular, an alloy of steel and / or aluminum. 10. A domestic appliance component according to any of claims 6 to 9, wherein the heating device (3) is configured to heat the carrier 25 (1) at said predetermined temperature by one or more of between induction heating, electric heating, and radiant heating. Domestic appliance component according to any of claims 6 to 10, wherein the desiccant (2) is chemically inert. Domestic apparatus, which is configured to carry out a method according to any of claims 1 to 5 and / or which comprises at least one component of a household appliance according to any of claims 6 to 11. 13. Household appliance according to claim 12, which is configured as a dishwashing machine, as a dryer, as a washing machine, as a microwave oven, and / or as a steam oven.

14.

Household appliance according to claims 12 or 13, and which further comprises a control device, which is configured to generate control signals to direct the heating device (3).

fifteen.

Household appliance according to claim 14, wherein the control device is configured to generate the control signals based on the state relative to the load of the desiccant (2) with fluid.