JPS61259728A - Dehumidifying apparatus - Google Patents

Abstract

PURPOSE:To enhance energy efficiency, to eliminate restriction from the aspect of material quality by corrosion, and to dispense with the taking-in of the open air, by providing a pressure reducing means and a steam compression means to the condensation part of a hygroscopic solution and compressing generated steam to reutilize the same as an evaporation heat source. CONSTITUTION:The hygroscopic solution, which absorbed moisture of the exhaust air from a process 3 to be diluted in a dehumidifying part 1, is pumped up from a liquid sump. part 2' by a pump 10 and sprayed to a stream heater 13 from the spray apparatus 12 in a condensation part 8. A heater 13 is heated by steam from an external heat source only at the initial period of operation. The moisture in the diluted solution sprayed under reduced pressure in the condensation part 8 by a vacuum pump 14 is evaporated at low temp. and the condensed solution is returned to the dehumidifying part 1 by a pump 17. The steam evaporated by the heater 13 is compressed by a compressor 16 to form heated steam which is, in turn, supplied to the heater 13 through a steam reflux passage 15.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a dehumidifying device in which moisture in the air is adsorbed using a hygroscopic solution, such as an aqueous lithium chloride solution, and the solution is concentrated and circulated.

[Background of the invention]

-m, the liquid dehumidifier (using lithium chloride aqueous solution) consists of two pieces of equipment: a dehumidification tower and a regeneration tower. A dehumidification tower may be used, for example, to collect return air from a film manufacturing process (100
% saturated air) through a lithium chloride spray solution,
The regeneration tower adsorbs moisture in the air and supplies it to the drying process.The regeneration tower uses a steam heater to evaporate the moisture from the lithium chloride aqueous solution whose concentration has decreased due to moisture adsorption, concentrates it, and returns it to the dehumidification tower. It is something that makes you

However, the liquid dehumidifier described above requires a heat source for the steam heater used when concentrating the solution in the Al regeneration tower, and has low energy efficiency. (b) Since the regeneration heater is used at a high temperature, Corrosivity increases, there are material restrictions, and equipment costs increase. (C)
In order to remove the evaporated vapor from the regeneration tower, outside air is taken in, but this tends to stain the liquid and clog the spray nozzle. (d) Because outside air is taken in, the number of times lithium chloride is replaced has increased.

[Purpose of the invention]

This invention is intended to solve the above problems all at once.
It is an object of the present invention to provide a dehumidifying device that compresses and reuses the latent heat of vaporization generated during solution concentration to improve energy efficiency and allows a closed-loop solution circulation path.

[Structure of the invention]

In order to achieve the above object, the present invention includes a dehumidifying section that adsorbs moisture in the air into a hygroscopic solution, and heating and evaporating excess moisture in the diluted solution in the dehumidifying section, and refluxing it to the dehumidifying section as a concentrated solution. A concentrating section is provided, and the concentrating section is equipped with a pressure reducing means and a compressing means for compressing the vapor and refluxing it as a source of heat of evaporation.

〔Example〕

Next, the present invention will be explained based on an embodiment shown in the attached drawings. The head of the housing 2 is provided with an inlet 4 for air (moisture saturated air) discharged from a process cell 3 for example in film production, and an outlet 5 for returning air after dehumidification to the process 3. At the air inlet 4, the air from the process 3 is sprayed with a hygroscopic solution.

Spray device 6 for adsorbing moisture in the air to the particles
Then, the solution accumulated in the housing 2 becomes high temperature due to adsorption heat generated when water adsorbs to the solution particles, and the outflow port 5
A cooler 7 is provided to control the temperature of the dehumidified air that returns to process 3 from the process 3.

Reference numeral 8 denotes a concentrating section that heats and evaporates surplus moisture in the diluted solution by adsorbing moisture in the dehumidifying section 1, and the concentrating section 8 includes a solution reservoir section 2 of the dehumidifying section 1 in a sealed housing 9. ' is equipped with a spraying device 12 that communicates with the pump 10 through an introduction path 11 having a pump 10 in the middle, and a steam heater 13 that evaporates water in the solution sprayed by the spraying device 12. Low temperature (e.g. 74
The vacuum pump 14 reduces the pressure inside the housing 9 so that moisture can be evaporated at a temperature of 15°F (°C), and the steam evaporated by the heat of the steam heater 13 is extracted and compressed as heated steam via the steam return path 15 to the steam heater 13. It is equipped with a compressor 16 that supplies the air. The concentrated solution from which excess water has been removed in the concentration section 8 is returned to the spray device 6 provided in the dehumidification section 1 via a concentrated solution return path 18 having a pump 17 in the middle.

Reference numeral 19 denotes an introduction path 11 for introducing the diluted solution from the liquid reservoir 2' of the dehumidification section 1 to the spray device 12 of the concentration section 8, and a reflux path for refluxing the concentrated solution from the concentration section 8 to the spray device 6 of the dehumidification section 1. The economizer provided at the intersection with 18 transfers the heat of the high temperature solution passing through the reflux path 18 to the low temperature solution passing through the introduction path 11, making it possible to reduce the capacity of the cooler 7 of the dehumidification section 1.

Next, the operation of the above embodiment will be explained.

The air discharged from the process 3 comes into contact with the particles of the hygroscopic solution sprayed by the spray device 6 at the inlet 4 of the dehumidifier 1, is dehumidified, is cooled by the cooler 7, and returns to the process 3 from the outlet 5. The diluted solution adsorbs water in the dehumidifying section 1 and collects in a reservoir section 2' provided at the bottom of the housing 2, is pumped up by the pump 10, passes through the introduction path 11, and is stored in the housing of the concentrating section 8. The water is sprayed from the spray device 12 to the steam heater 13. This steam heater 1
3 is heated by steam from an external heat source (steam generator) in the initial stage of operation, and the water in the diluted solution sprayed onto it evaporates. In this case, since the pressure inside the housing 9 of the concentration section 8 is reduced by the operation of the vacuum pump 14, 1
Evaporates at temperatures below 00°C (for example, 74°C). The solution concentrated by the evaporation of water is pumped out by a pump 17,
The concentrated solution is refluxed through the reflux path 18 to the spray device 6 provided in the dehumidifying section 1, and is sprayed in order to come into contact with the saturated air discharged from the process 3. On the other hand, the steam evaporated by the steam heater 13 is compressed! ia1.6, is pressurized and compressed, and is supplied as heated steam to the steam heater 13 through the steam recirculation path 15. That is, the steam heater 13 is heated using steam from an external heat source (steam generator) at the beginning of its operation, but during operation it is heated using its own latent heat of vaporization as a heat source, and after that it is heated using steam from an external heat source (steam generator). No heat source is required. Of course, driving the compressor 16 requires external power (electricity), but the energy used for this power is compared to the energy used to drive the external heat source.

It is significantly smaller, so the energy consumption of one device is 1/30 of that of the conventional device.

Further, while the solution that has become low temperature in contact with the cooler 7 of the dehumidifying section 1 and accumulated in the liquid reservoir section 2' passes through the introduction path 11 and is introduced into the spray device 12 of the concentrating section 8, the vapor of the concentrating section 8 is The concentrated solution heated by the heater 13 and refluxed to the spray device 6 of the dehumidifying section 1 through the reflux path 18 is cooled in the economizer 19. In other words, introduction route 11
The low temperature solution passing through the reflux path 18 is heated, and the high temperature solution passing through the reflux path 18 is cooled, so that the amount of heat of the heater in the concentration section 8 and the amount of heat of the cooler in the dehumidification section can be saved.

〔Effect of the invention〕

As described above, the dehumidifying device according to the present invention includes a dehumidifying section that causes a hygroscopic solution to adsorb moisture in the air.

a concentrating section for heating and evaporating surplus water in the diluted solution in the dehumidifying section and returning it to the dehumidifying section as a concentrated solution;
Since the concentrating section is equipped with a pressure reduction means and a compression means for compressing the vapor and refluxing it as an evaporative heat source, the external steam heater that removes excess moisture in the hygroscopic solution that has adsorbed moisture in the air can be used. A heat source is required only at the beginning of operation and is not required thereafter, which not only improves energy efficiency, but also reduces the pressure in the condensing section and evaporates at low temperatures, making it possible to reduce the amount of material used in conventional systems that use heaters at high temperatures. There are no restrictions and equipment costs can be reduced. Also,
According to this invention, all the vapor evaporated in the concentration section is recovered and reused as a heating heat source, and the operation can be performed in a completely closed loop, so there is no need to take in outside air, and there is no need to prevent the solution from becoming dirty or clogging the spray nozzle. It has various excellent effects such as no generation of water, and the number of times of solution replacement can be significantly reduced.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. 1.--Dehumidification section 3-.Process 6.12-.
- Spraying device 7 - Cooler 8 - Concentration section
10.17-Pump 11--Introduction route
13.--Steam heater lt--.Vacuum pump
15--Vapor recirculation path 16--Compressor 1
8-Concentrated solution reflux path 19-・Economizer-

Claims (2)

[Claims] (1) A dehumidifying section for adsorbing moisture in the air into a hygroscopic solution, and a concentrating section for heating and evaporating surplus moisture in the diluted solution in the dehumidifying section and returning it to the dehumidifying section as a concentrated solution, A dehumidifying device characterized in that a concentrating section is equipped with a pressure reduction means and a compression means for compressing vapor and refluxing it as an evaporative heat source. (2) The dehumidification device according to claim 1, wherein an economizer is disposed at the intersection of a path for introducing the diluted solution into the concentration section and a path for refluxing the concentrated solution to the dehumidification section.