JPS61129019A - Absorbing type temperature circuit - Google Patents

Abstract

PURPOSE:To separate fine liquid droplets with high accuracy, by using an aqueous solution of a chemical substance low in steam partial pressure and mounting an aqueous solution concentrator and a dilution device while arranging a membrane selectively permeating only steam along the boiling surface of the aqueous solution concentrator. CONSTITUTION:In a concn. unit 101', the steam from a dilute solution 13 introduced into a concn. chamber 34 and boiled and evaporated under heating, and accompanied splash are filtered by a hydrophobic membrane 55 and the splash is prevented from transmission while only steam is transmitted through said membrane 55 to be condensed under cooling. In a dilution absorber 102', water droplets accompanied by steam generated from an evaporator 24 are perfectly separated by a hydrophobic membrane 45 and only pure steam is absorbed with a concentrate 11 in an absorbing chamber 23 and, therefore, dilution is entirely performed by the absorption of steam and latent heat of condensation is perfectly recovered.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention uses an aqueous solution of a chemical substance with a low water vapor partial pressure, such as an aqueous lithium bromide solution, and heats the aqueous solution to boil it to release the generated water vapor. An aqueous solution concentrator that cools and condenses water, and a diluter that absorbs water vapor generated by heating and boiling water into a concentrate made from the concentrate, and is configured to obtain cold or hot heat. This relates to an absorption type temperature regenerator.

FIG. 4 is a system diagram for explaining the structure of this type of temperature regenerator.

The basic system of this temperature regenerator is the concentration unit 101
and a dilution unit 102. The concentration unit 101 described above includes a concentration chamber 34 and a condensation chamber 33, and the dilution unit 102 described above includes an evaporation chamber 24 and an absorption chamber 23.

The principle of the absorption type temperature regenerator is to utilize the hygroscopicity of an aqueous solution such as lithium bromide, and when the concentrated liquid absorbs water vapor in a closed space, it generates heat due to condensation heat and dilution heat, which generates high-temperature energy. There are two methods: one is to generate low-temperature energy (absorption heat pump), and the other is to generate low-temperature energy by utilizing the lower water vapor pressure and evaporation of water at a lower temperature (absorption chiller).

A specific explanation will be given below using a lithium bromide aqueous solution as an example.

60% concentration in the absorption chamber 23 of 102 (dilution unit in Figure 4)
A lithium bromide aqueous solution is poured into the evaporation chamber 24, water is poured into the evaporation chamber 24, and the chamber is evacuated. Lithium bromide, which is highly hygroscopic, has a low water vapor partial pressure, so it does not evaporate, but only the water in the evaporation chamber 24 evaporates even at the same temperature, and the water in the evaporation chamber 24 loses its latent heat of evaporation to a lower temperature. goes down. On the other hand, absorption chamber 2
The lithium bromide in 3 is the water vapor 1 generated in the evaporation chamber 24.
4 and generates heat due to its condensation heat and dilution heat, causing the temperature to rise. This phenomenon can be explained by the vapor pressure diagram (Dthring diagram) of the lithium bromide aqueous solution shown in FIG. For example, when low-temperature thermal energy of about 50 C is supplied to the evaporation chamber 24 to evaporate water at 40 C, the absolute pressure inside the dilution unit 102 becomes 57 mHg. The generated water vapor is absorbed into a lithium bromide aqueous solution with a concentration of 60%, generating heat and simultaneously diluting the aqueous solution. Aqueous solution concentration is 55
%, the absorption temperature at that time is 75C and 71
- Thermal energy at a high temperature of about 70C can be obtained from the absorption chamber 23. On the other hand, if the 55% concentration lithium bromide aqueous solution in the absorption chamber 23 is kept at 40C by avoiding external heat, the absolute pressure inside Enit will drop to 9.3151 Hg, and the lithium bromide solution in the evaporation chamber 24 will be The water evaporates rapidly and the temperature drops to about 9.10C, and thermal energy at a lower temperature of about 15C is obtained from the evaporation chamber 24.

Generally, the water vapor partial pressure of a hygroscopic aqueous solution decreases rapidly as the concentration increases, and the temperature difference between supplied energy and obtained thermal energy increases. However, the performance of absorption systems also depends on concentrating the aqueous solution to higher concentrations in the concentrating unit.

As described above, in the absorption system, water concentrated in the concentration unit 101 enters the evaporation chamber 24, evaporates, and the temperature drops until 9.
The generated water vapor 14 is transferred to the absorption chamber 23 and the concentration unit 10.
It is absorbed by the concentrated liquid 11 supplied from 1 and generates heat. To obtain high-temperature thermal energy, if heat is supplied so that the temperature of the evaporation chamber 24 does not drop, heat higher in temperature than the supplied heat can be obtained from the absorption chamber 23. In addition, in order to obtain low-temperature thermal energy, heat at a temperature lower than the absorption chamber temperature is supplied so that the temperature of the absorption chamber 23 does not rise, and when the heat is cooled from the absorption chamber 23, the heat is supplied from the evaporation chamber Heat at a lower temperature than heat (cooling) can be obtained. Dilution unit 102
The water 12 supplied to the evaporation chamber 24 becomes water vapor 14 and is absorbed by the concentrated liquid 11 in the absorption chamber 23, resulting in diluted diluted liquid i1.
3 enters the concentration unit 101 again.

In order for the above-described absorption type temperature regenerator to perform the desired function, it is necessary to remove the fine droplets contained in the steam generated by boiling and circulate pure steam. The technology for removing droplets is reported in detail in ``Absorption Refrigerating Machines and Their Applications,'' edited by the Japan Refrigeration Association.

In the method shown in the above-mentioned document, a wave-shaped scrubber is provided through a space with respect to the boiling evaporation surface, and the scrubber removes fine droplets, and the part of the space is a part of the fine droplets. It is provided to allow relatively large droplets to fall freely and separate them. Even if the droplets to be separated are relatively large, their diameter is on the order of microns, so they gradually descend while partially suspended in the steam. Therefore, it is not possible to increase the steam in this area.

Further, the scrubber provided to remove fine droplets cannot keep up with the steam velocity because its removal performance decreases as the steam velocity increases. Therefore, due to steam velocity limitations in the space and part of the scrubber, it is necessary to increase the space volume, which increases the size of the apparatus.

In the prior art absorption temperature regenerator shown in FIG. 4, the dilute liquid 13 is heated in the concentration chamber 34 of the concentration unit 101. At this time, since the concentration unit 101 is under reduced pressure, the diluted liquid boils and evaporates. Since there are droplets containing lithium bromide in this water vapor, the droplet remover 3
After removing the water vapor 14, only the water vapor 14 is introduced into the condensation chamber 33, where it is cooled, condensed, and condensed. If the droplets are not separated by the droplet remover 35, the condensation chamber 3
If lithium bromide is mixed into the condensate, pure water cannot be obtained, and the lithium bromide concentration in the condensate gradually increases. If you are unable to do so, you will be unable to drive. Currently, to avoid this, pure water is replaced and lithium bromide aqueous solution is replenished periodically.

Therefore, the removal performance of the droplet remover 25.35 is important, and in order to improve this performance, the concentration chamber 3
4. The space volume of the absorption chamber 23 is increased to reduce vapor velocity, and relatively large particles in the entrained droplets are separated by free fall, and the remaining droplets are further separated by the droplet remover 25.35. In this case as well, the removal performance is related to the steam velocity, so the volume is critical.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and is an absorption type temperature control system that has good separation performance for fine droplets in steam, has a large tolerance for the maximum flow rate of steam, and allows the entire device to be made compact. The aim is to provide a regenerator.

[Summary of the invention]

In order to achieve the above object, the present invention has the basic configuration of the absorption type temperature regenerator explained with reference to FIG. It is equipped with an aqueous solution concentrator that cools and condenses the water vapor generated, and a diluter that absorbs the water vapor generated by heating and boiling water into a concentrated liquid made from the above-mentioned concentrated liquid. An absorption type temperature regenerator with a structure to obtain the above was improved, and a membrane was constructed that selectively allows vapor to pass through and blocks liquid from passing through, and the membrane was arranged along the boiling surface of the aqueous solution concentrator. It is characterized by

[Embodiments of the invention]

Next, one embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG.

This embodiment is an example of improving the absorption type temperature regenerator according to the prior art shown in FIG. 4 by applying the present invention.
In the figure (this example), members given the same drawing reference numbers as in FIG. 4 (prior art example) are the same or similar components as in the prior art.

The differences between this example (FIG. 1) and the conventional example (FIG. 4) will be described below.

In the concentration unit 1011 in this example, a hydrophobic porous membrane 55 is disposed in the steam passage between the concentration chamber 34 and the condensation chamber 33, and in the dilution unit 102', the steam passage between the evaporation chamber 24 and the absorption dilution chamber 23 is disposed. A hydrophobic porous membrane 45 is arranged in the passage.

According to the present invention, the water vapor 14 from the dilute liquid 13 introduced into the concentration chamber 34, heated and boiled and evaporated, and accompanying droplets are filtered by the hydrophobic membrane 55, and the droplets do not pass through, only the water vapor 14 passes through, and the water vapor 14 is cooled. and condensed water. This condensate is pure water. On the other hand, in the dilution absorber 102', entrained water droplets in the water vapor 14 generated in the evaporator 24 are completely separated by the hydrophobic membrane 45, and in the absorption chamber 23, only pure water vapor 14 is absorbed into the concentrated liquid 11. All dilution is absorption of steam and is completely recovered as latent heat of condensation.

FIG. 2 is a chart showing an example of the ventilation resistance of the hydrophobic porous membrane used in the present invention, and as the pore diameter increases, the pressure loss naturally decreases. Further, FIG. 3 schematically shows the state of water vapor permeation through the hydrophobic porous membrane based on observation under a microscope, and the hydrophobic porous membrane 1 has pores 2. In FIG. Even if the water vapor 14 containing the droplet 4 approaches the membrane, the droplet 4 cannot come into contact with the membrane 1 because it is hydrophobic, and a boundary line shown by a broken line 10 is formed, and the droplet 4 is not transmitted. Therefore, droplets with a particle size smaller than the pore size can also be separated. This phenomenon can be explained by the fact that in the relationship between the pore diameter and pressure loss shown in FIG. 2, when the pore diameter is 5 μm or more, the pressure loss decreases rapidly even if the flow velocity V is high. That is, when the pore diameter becomes 5 μm or more, the gas-liquid boundary line 10 shown in FIG. 3 does not coincide within the pore and becomes open, allowing the droplet 4 to pass through. From the above microscopic observation, practical effects can be exhibited by setting the pore diameter of the hydrophobic porous membrane to 1 μm to 5 μm.

FIG. 6 shows another embodiment of the present invention, in which the hydrophobic porous membrane 55 is provided only in the concentration unit 101, and is an example in which only the prevention of splashes from the concentrate side is provided. .

As described above, according to the temperature regenerator of this embodiment, it is possible to separate droplets contained in water vapor, and furthermore, it is possible to form a φ type. Further, the effects of the present invention can be further exhibited when the concentration is increased. In other words, as mentioned above, the higher the concentration in the concentrator, the wider the range of change in cold and heat in the dilution unit. Since the droplets tend to increase, a hydrophobic porous membrane like the one in this example becomes extremely effective.

〔Effect of the invention〕

As described in detail above, according to the absorption type temperature regenerator of the present invention, fine droplets contained in steam can be separated with high precision, and the flow rate of steam can be kept relatively high, so that the entire device This has an excellent practical effect in that it can be configured to be small and lightweight.

[Brief explanation of drawings]

Figure 1 is a system diagram showing one embodiment of the absorption type temperature regenerator of the present invention, Figure 2 is a chart showing the relationship between pore diameter and pressure loss, and Figure 3 explains the characteristics of a hydrophobic porous membrane. Schematic diagram, 4th
The figure is a system diagram showing an example of a conventional absorption temperature regenerator.
The figure is a chart showing the relationship between temperature and vapor pressure, and FIG. 6 is a system diagram of an embodiment different from the above. DESCRIPTION OF SYMBOLS 1... Hydrophobic porous membrane, 2... Pore, 11... Concentrated liquid, 12... Water, 13... Dilute liquid, 14... Water vapor, 23... Absorption chamber, 24 ...evaporation chamber, 25...
Droplet remover, 33... Condensation chamber, 34... Concentration chamber, 3
5... Splash remover, 45... Hydrophobic porous membrane, 55
... Hydrophobic porous membrane, 101.101'... Concentration unit, 102.102'... Dilution unit.

Claims (1)

[Claims] 1. An aqueous solution concentrator that uses an aqueous solution of a chemical substance with a low water vapor partial pressure, heats the aqueous solution to boiling, and cools and condenses the generated water vapor; and In a temperature regenerator that is equipped with a diluter that absorbs the generated water vapor into a concentrated liquid made from the above-mentioned concentrated liquid, and which obtains at least one of cold heat and warm heat, the vapor is selectively permeated to form a liquid. An absorption type temperature regenerator, comprising a membrane that blocks permeation, and the membrane is disposed along the boiling surface of the aqueous solution concentrator. 2. The absorption type temperature regenerator according to claim 1, wherein the membrane is provided at a distance from the boiling surface. 3. The absorption type temperature regenerator according to claim 1, wherein the membrane is a hydrophobic porous membrane with a pore diameter of 1 to 5 μm.