ES2389643A1 - Adaptable evaporator and absorbing compound of flat plate. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Evaporator and adiabatic flat sheet absorber assembly. An absorption machine is described that has an evaporator and an absorber in the same container. In said absorber, the lithium bromide solution is sprayed in the form of a flat sheet and without heat exchange (adiabatic). The heat transfer is carried out in another heat exchanger, which can be dissolution-air or solution-water. (Machine-translation by Google Translate, not legally binding)

Description

FLAT SHEET ADAPTER ADAPTER AND ABSORBER ASSEMBLY

OBJECT OF THE INVENTION

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The present invention relates to an absorption machine with an operation based on the absorption of lithium-water bromide with air conditioning and cooling applications.

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BACKGROUND OF THE INVENTION The development of refrigeration revolutionized the processing and distribution of food by modifying the consumption habits of mankind. The implementation of the cold chain allows the capture, process, refrigeration, freezing, storage and distribution of the most varied food products, being able to have them with the highest standards of freshness and quality, anywhere in the world and at any time of the year. Another application that has been extended in advanced societies is the air conditioning of buildings.

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Refrigeration and air conditioning technology uses, in most applications, refrigerating machines that work with refrigerants (CFCs, HCFCs and HFCs) that destroy ozone (CFCs and HCFCs) and generate a greenhouse effect far superior to that generated by CO2 . As these machines, in most cases, use electricity, their operation also generates carbon dioxide.

As a consequence of these inconveniences the Protocol was developed

from Montreal, to prevent the destruction of ozone and the Kyoto agreement to

reduce the emission of greenhouse gases.

To the above effects, we must add the use of water to produce the

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electricity, and water consumption in cooling towers. The use of towers

generates in turn epidemics of legionellosis, recurrent disease

in the media.

However, today's society cannot do without technology

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refrigerator, and for this reason it is necessary to create cold production systems

that minimize its environmental impact.

A possible solution could happen by replacing the refrigerants

fluorinated, which we will generally call "organic refrigerants" by others

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gases that in current refrigeration technology are referred to as "refrigerants

inorganic or natural. "Refrigerants such as ammonia, water, CO2 not

they destroy ozone, nor generate greenhouse effect. Other refrigerants such as

propane or butane, among others, do not destroy ozone and its greenhouse effect

It is comparable to CO2. However, ammonia, due to its toxicity, has

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strong conditions for its application and fuels are prohibited from

use in domestic or commercial facilities. Carbon dioxide has

serious energy efficiency and safety problems due to high pressures

of work and although it begins to be used in the tourism car sector

It is not used in the residential sector.

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Therefore, there would only be the option of water that in a state of steam, is

the most potent greenhouse gas. The use of water as a refrigerant does not

increases the greenhouse effect of the planet, since a possible leak does not

Modify the water balance. Its physical and thermodynamic properties only

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allow it to be used to generate a temperature higher than QºC. This is not a

problem for the air conditioning and temperature cooling sector

working range between 7ºC and 16ºC.

The first industrial applications of the thermodynamic principles of the absorption of a vapor by a liquid, in order to achieve the cooling of another liquid, date from the mid-19th century.

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The large-scale commercialization of absorption refrigeration plants with the Ammonia-Water cycle begins at the beginning of the 19th century and the placing on the market of the first plants with the Water-Lithium Bromide cycle takes place at the beginning of the 50s.

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The absorption cycles are physically based on the ability of some substances, such as water and some salts such as Lithium Bromide, to absorb, in liquid phase, vapors of other substances such as Ammonia and water, respectively.

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In an absorption machine a process takes place in which the refrigerant, water, ammonia or others, evaporates in the evaporator taking the heat of change of state of the fluid that circulates inside the tubular beam of this exchanger. The vapors produced are absorbed by the absorbent, water or solution of lithium bromide or others, in a dissolution process in which its temperature rises, which requires external cooling for the solution to remain in correct temperature conditions and not Increase the pressure in the chamber in which absorption occurs and is called Absorber.

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Water cooling towers are normally used in this external cooling circuit. The water cooled in the tower is circulated through the interior of the tubular beam of another exchanger that is located inside the absorber chamber and on which the absorbent is sprayed to facilitate the absorption process. The mass of absorbent containing the absorbed refrigerant is transported, by pumping, to another heat exchanger whose function is to separate the refrigerant from the absorbent, by distillation of the former. This heat exchanger is called

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generator. The hot fluid, normally water or water vapor, is circulated through its tubular beam, which is the main source of energy for the operation of the absorption cycle, and which can also proceed as an effluent from any type of process in which it is generated residual heat

DESCRIPTION OF THE INVENTION

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The assembly object of the invention is intended for use in machines belonging to the group of the aforementioned absorption machines, more specifically those that use lithium bromide and water.

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The evaporator-absorber assembly comprises a container in which there is a collector (or several) that receives the hot and concentrated solution of lithium bromide from a generator, collector (or collectors) from which a series of welded ducts leave perpendicularly on the outer surface of the collector they have threaded sprayers at the free end of said ducts, which spray said solution forming flat sheets that come into contact with water vapor.

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The flat sheets show an essentially triangular configuration to increase the exchange surface with the steam so that dilution of the concentrated solution that will fall to the bottom of the tank is favored. From the bottom of the tank a return line to the generator and a recirculation line directed to the collector starts again with the intermediation of an exchanger that can be of air or water that decreases the temperature of the solution directed again to the collector. This effect facilitates mass transfer and, since the absorption process is adiabatic, heat transfer is done in need of less exchange area.

In addition, these essentially triangular flat sheets allow

the process is carried out in non-static situations, that is, in motion,

since the spray in laminar form allows certain rocking or swings

without pulverized flat sheets being excessively influenced

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for these movements; making the use of this especially appropriate

machine in installations that are subject to movement such as ships,

land vehicles, etc.

The absorber configuration allows the machine size

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absorbed ora can be really small offering very high efficiencies.

In addition, the absorber-evaporator assembly object of the

invention can have an evaporator in the same tank, improving

even more the final dimensions, advantage already mentioned for the absorber, and

which would also affect the final dimensions.

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In this case where the machine incorporates the evaporator and absorber

in the same space, both make up a single container that has

a separating insulating wall perpendicular to the base of the container that

generates two spaces or chambers that allows the mixing of gases or steam from

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water in the upper part since said wall does not reach the top or surface

top of the container. The evaporator is in a chamber and

it comprises a bundle of tubes that make up a circuit through which liquid circulates

of secondary refrigeration normally coming from the room to cool,

leaving the tubes that are located at the top of the chamber at a

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temperature higher than that of the tubes located in the lower part of the chamber

or vice versa, closer to the base of the container, where the liquid circulates

secondary refrigerant that has cooled as it passes through the complete circuit of the

coil.

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In this evaporator, the water that reaches this chamber from the

condenser undergoes evaporation. The water, once evaporated, passes, in

Water vapor form, to the adjacent chamber.

In this second absorber chamber described above from the first chamber.

next to the first one is the one in which the water vapor is introduced

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The described configuration is valid for both single-acting and double-acting or even triple-acting absorption machines. Depending on what type of collector one, two or three lines of hot concentrated solution would come from two generators, as well as one, two or three water inlets from a condenser.

DESCRIPTION OF THE DRAWINGS

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To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical implementation thereof, a set of drawings is attached as an integral part of said description. where, for illustrative and non-limiting purposes, the following has been represented:

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Figure 1. Shows a simple effect machine scheme. of the evaporator-absorber assembly the

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Figure 2.- Shows a longitudinal section of the evaporator-absorber assembly of the single-acting machine. Figure 3. Shows a diagram of the evaporator-absorber assembly of the double-acting machine.

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Figure 4.- Shows a longitudinal section of the evaporator-absorber assembly of the double-acting machine.

Figure 5.-Shows the sprayer and the nozzle.

PREFERRED EMBODIMENT OF THE INVENTION

In a preferred embodiment of the invention the absorber assembly and

evaporator (1) is applied in single acting machines as represented in

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Figures 1 and 2; as seen in these figures the set of

absorber and evaporator (1) comprises a container (10) where it is located

an evaporation chamber (12) and an absorption chamber (13) separated by

a vertical wall (9) that allows the passage of steam from one chamber to another through the

upper part of the container (10), since the separating wall (9) does not reach up to

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the upper part of the container (10).

At least one supply line arrives at the evaporation chamber (12)

of water (18) through which water is delivered to the inside of this chamber

where is an evaporator (2) comprising a liquid circuit

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refrigerant (8), formed by tubes (3), through which coolant circulates

hot secondary (approximately 10ºC18º C) through the tubes (3)

upper and cooler secondary coolant (approximately 7ºC

15 ° C) through the lower tubes (3), secondary coolant that can be

aimed at a room to cool, a cold room, a greenhouse, etc. To the

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the water comes into contact with the coolant circuit tubes (8)

that are hot, and because the water is at very low pressure

(approximately 10 mbar), the water evaporates and rises inside the

evaporation chamber (12) overcoming the vertical wall separator (9) arriving

to the absorption chamber (13).

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In this absorption chamber (13), the water vapor coming from the

evaporation chamber will come into contact with a bromide solution of

lithium from a dissolution manifold (7) powered by a line of

entrance (15) and a recirculation line (17) with the intermediation of a

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heat exchanger (6). From this dissolution manifold (7) the

bromide solution by means of sprayers (5) coupled to ones

conduits (11) welded to the dissolution manifold (7). This spray forms

flat sheets (4) of lithium bromide solution that favor dilution of the solution of lithium bromide with steam.

the

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The exchange process occurs while the flat sheet (4) of dissolution is in direct contact with the evaporated water.

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Once the dissolution sheet is detached, it first falls into an absorption solution tank (14) located at the bottom of the absorption chamber (13) from where, once diluted, it will circulate again through the return line (16 ) to reach the generator and restart the process described above. Likewise, the content of said absorption solution tank (14) is carried through a recirculation line (17), with the intervention of the exchanger (6), to the dissolution manifold (7) of the absorption chamber (13) of the container (10), starting again the absorption process. In this first embodiment of the invention the heat exchanger (6) is of the air-dissolution type.

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In another embodiment of the invention the whole process is exactly the same, except for the heat exchanger (6), which in this case would be of the water-dissolution type.

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Both embodiments are also applicable to a double-acting machine shown in Figures 3 and 4, which comprise two input lines (15) corresponding to a high and a low generator.

Claims (7)

1.-Absorber and evaporator assembly (1) comprising:

a container (10) which reaches at least one input line (15) of

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concentrated and hot absorbent solution from at least one

generator, and

at least one water supply line (18) coming from a

condenser,

a return line (16) leaving the container (10) towards the

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generators of the diluted and cooled solution,

a recirculation line (17) that starts from the container (10) with

intermediation of an exchanger (6) that goes back to the container

(10),

a collector (7) located inside the container (10) that receives the line

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of input (15), which is provided with conduits (11) coupled in its

surface and that also receives the recirculation line (17),

characterized in that at the free end of the ducts (11) it comprises some

sprayers (5) configured to generate a series of sheets

flat (4) parallel dissolution and essentially triangular configuration that

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comes into contact with water vapor for refrigerant dilution.

2. Absorber and evaporator assembly (1) according to claim 1

characterized in that the closed container (10) has a vertical wall

separator (9) insulator that defines two cameras communicated by you

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higher;

an evaporation chamber (12) defined on one side of the vertical wall

separator (9) comprising an evaporator (2), and

an absorption chamber (13) defined on the other side of the vertical wall

separator (9).

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3.-Absorber and evaporator assembly (1) according to claim 1 characterized in that the evaporator (2) comprises a liquid circuit secondary refrigerant (8) formed by tubes (3). 4. Absorber and evaporator assembly according to claim 1 characterized in that the exchanger (6) is air. 5. Absorber and evaporator assembly according to claim 1 characterized in that the exchanger (6) is water. 6.-Absorber and evaporator assembly according to claim 1 characterized in that it comprises two input lines (15) intended to be associated with corresponding generators. 7.-Absorber and evaporator assembly according to claim 1 characterized in that it comprises three input lines (15) intended to be associated with corresponding generators.