JPS6223416A - Apparatus for dehumidifying and drying compressed air - Google Patents

Abstract

PURPOSE:To surely dehumidify and dry even high pressure and high temp. compressed air emitted from an air compressor with a high compression ratio by certainly cooling the same, by stepwise cooling compressed air after precooling by a re-heating heat exchanger, an air cooling after-cooler and an air cooling heat exchanger. CONSTITUTION:High temp. and high pressure compressed air emitted from an air compressor 2 is introduced into a precooling heat exchanger 3 to be precooled through the heat exchange with cold water and the open air and subsequently heat-exchanged with cooled compressed air by a re-heating heat exchanger 11 to be cooled while the cooled compressed air is heat-exchanged with a large amount of the open air in air cooling after-cooler 4 to be further cooled and adjusted to temp. equal to or less than a dew point to condense moisture in compressed air. Thereafter, moisture separated compressed air is heated by the re-heating heat exchanger 11 to lower relative humidity and supplied to pneumatically operated machinery as dry compressed air.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an apparatus for dehumidifying and drying compressed air.

<Prior art> When the temperature of compressed air drops to room temperature, the moisture contained in the compressed air becomes water and condenses. If this is supplied as is, it will cause problems for various air-operated equipment.
In order to solve this problem, various compressed air dehumidifying and drying devices have been proposed and put into practical use, which obtain dry compressed air by cooling the compressed air and then reheating it to the same temperature as room temperature. has been done. However, since conventional dehumidifying and drying devices were designed for compressed air discharged from an air compressor with a relatively low compression ratio, the air pressure li! When the temperature of the air discharged from the machine reaches, for example, 300° C., there is a problem that sufficient dehumidification is not always possible because there is a limit to the cooling power.

The present invention has been made to solve the above problems, and its purpose is to reduce the air pressure f6a with a high compression ratio.
To provide a compressed air dehumidifying and drying device capable of accurately cooling and reliably dehumidifying and drying even high-pressure, high-temperature compressed air discharged from m.

<Means for solving the problem> A flow of outside air induced by blowing out a part of the compressed air discharged from a water-cooled air compressor that sucks in and compresses outside air, and a flow of water and the compressed air. an air cooling aftercooler that exchanges heat between the compressed air discharged from the precooling heat exchanger and outside air; and an air cooling system that exchanges electric heat with the compressed air and water flowing out from the air cooling aftercooler. a heat exchanger; a reheating heat exchanger for exchanging heat between compressed air flowing out from the air cooling heat exchanger and compressed air flowing from the precooling heat exchanger to the air cooling aftercooler; the precooling heat exchanger, and the air cooling heat exchanger; A compressed air dehumidifying and drying device is provided with a cooling heat exchanger, a refrigeration cycle that cools water that is circulated and supplied to the air compressor, and an oil cooler that cools lubricating oil of the air compressor.

<Operation> The high-temperature, high-pressure compressed air discharged from the air compressor is cooled in stages by a pre-cooling heat exchanger, an air-cooling aftercooler, and an air-cooling heat exchanger to condense and precipitate moisture, and then the cooled compressed air is cooled. Dry air is obtained by exchanging heat with the high-temperature compressed air headed for the air-cooled aftercooler to raise the temperature of the air.

(Embodiment) Fig. 1 shows an embodiment of the present invention, in which a water-cooled air compressor 2 that sucks and compresses outside air that has been collected by a filter l has a housing cooled by water. It is equipped with a compressor, an air-cooled motor, a gear train (all not shown), etc. that connect these, and the high-humidity, high-pressure compressed air discharged from the air compressor 2 is passed through a pre-cooling heat exchanger 3. It is installed in the air-cooled aftercooler 4.

The pre-cooling heat exchanger 3 uses a flow of outside air induced by injecting a part of the compressed air discharged from the air compressor 2 from a nozzle (not shown) and a flow of outside air from the cold water heat exchanger 5 via the water pump 6. It is composed of an air/water-cooled heat exchanger that exchanges heat between the circulating water and the compressed air.

The air-cooled aftercooler 4 is configured to exchange heat between the compressed air and air (flow of outside air) sent by a fan 8 driven by a motor 7.

An air cooling heat exchanger 9 is connected to the discharge port of the air cooling aftercooler 4. This air cooling heat exchanger 9 exchanges heat with compressed air and water that is circulated and supplied from the cold water heat exchanger 5 via the water pump 6. 10 is a drain for discharging water condensed by cooling to the outside of the vessel.

Further, at the discharge port of the air cooling heat exchanger 9, there is a recirculation system for exchanging heat between the compressed air discharged from the air cooling heat exchanger 9 and the compressed air headed from the precooling heat exchanger 3 to the air cooling aftercooler 4. The heating heat exchanger 11 is connected, and the compressed air discharged from the reheating heat exchanger 11 is used for various air production via piping (not shown)! It is being supplied to PIJ equipment.

On the other hand, the chilled water heat exchanger 5, which is connected to the precooling heat exchanger 3, the air cooling heat exchanger 9, and the compressor housing of the water-cooled air compressor 2 via a water pump 6, also serves as a refrigerant expander. Heat is exchanged between the wood and the refrigerant that is circulated and supplied from the refrigerant compressor 12 through the condenser 13. Reference numeral 14 designates a Guhring fan for forcing outside air into the condenser 13, and reference numeral 15 represents a motor for driving the cooling fan 14.

Further, the air-cooled aftercooler 4 includes an oil cooler 1.
By connecting this oil cooler 16 and the case (not shown) of a gear train (electric float) built in the air compressor a2 via an oil pump 17, lubricating oil and An oil cooler 16 exchanges heat with outside air.

In the configuration described in , the pre-cooling heat exchanger 3, the air-cooling heat exchanger 9, and the air compressor 2 include a cold tofu compressor 12 and a condenser 13.
Water (chilled water) kept at a low temperature is circulated and supplied in a refrigeration cycle consisting of a refrigeration cycle and a chilled water heat exchanger 5, etc., and a large amount of outside air is forcibly supplied to the air-cooled aftercooler 4□ by a fan 8. There is. Therefore, the high temperature (e.g. 300°C) compressed air discharged from the air compressor 2 is heat exchanged with water and outside air in the pre-cooling heat exchanger 3 to a temperature of 250 to 200°C.
cooled down to.

The compressed air that comes out of the pre-cooling heat exchanger 3 is heat exchanged with the previously cooled compressed air in the reheating heat exchanger 11 and cooled to about 180°C, and then cooled to about 180°C, and then cooled to a large amount of outside air in the air-cooling aftercooler 4. It is cooled to about 40°C through heat exchange. Then, in the air cooling heat exchanger 9, heat is exchanged with water (chilled water) and cooled to about 10°C, so the compressed air becomes at a temperature below the dew point, and the wood (moisture) contained in the compressed air is removed. is precipitated as water droplets and separated. Thereafter, the compressed air from which water has been separated in this way is heated to about 40° C. by heat exchange in the reheating heat exchanger 11, and its relative humidity decreases, so that it finally becomes dry compressed air. and is supplied to air-operated equipment (not shown).

It is needless to mention in detail that the water separated in the air cooling heat exchanger 9 is discharged from the drain 10 to the outside.

FIG. 2 shows another embodiment of the invention, in which:
Since this embodiment is basically the same as the previous embodiment, only the different parts will be explained and the description [J] of the same parts will be omitted.

That is, in the embodiment shown in FIG. 2, the condenser 13 of the refrigeration cycle is integrated with the air-cooled aftercooler 4, and the oil cooler 16 is constituted by a water-cooled oil cooler. Then, by returning the water flowing out from the air compressor 2 from the oil cooler 16 to the cold water heat exchanger 5 via the pre-cooling cooler 18, the temperature of the high-temperature wood is lowered by heat exchange with the outside air, and then the cold water is cooled. The heat is returned to the heat exchanger 5 to reduce the load on the refrigeration cycle.

Therefore, in the case of the embodiment shown in FIG. 2, the heat radiating means can be downsized, so the entire device can be constructed compactly.

<Effects of the Invention> In the present invention, the compressed air discharged from the air compressor is precooled, then cooled by a reheating heat exchanger, and then sufficiently cooled by an air cooling aftercooler and an air cooling heat exchanger to remove moisture. High compression ratio air compression Even the high-pressure, high-temperature compressed air discharged from the machine can be accurately cooled and reliably dehumidified and dried.

Furthermore, since the compressed air is cooled in advance by outside air and then finally cooled by water having a large specific heat, the intended purpose can be achieved without increasing the size of the heat exchanger.

[Brief explanation of the drawing]

FIG. 1 shows an example of the unreleased 151 J! FIG. 2 is a schematic diagram showing another embodiment of the present invention.

Claims (1)

[Claims] A water-cooled air compressor that takes in and compresses outside air, and a flow of outside air induced by blowing out a part of the compressed air discharged from the air compressor, and water and heat exchange between the compressed air. A pre-cooling heat exchanger, an air-cooling aftercooler for exchanging heat between the compressed air discharged from the pre-cooling heat exchanger and outside air, and an air-cooling heat exchanger for exchanging heat between the compressed air and water flowing out from the air-cooling aftercooler. and a reheating heat exchanger for exchanging heat between the compressed air flowing out from the air cooling heat exchanger and the compressed air heading from the precooling heat exchanger to the air cooling aftercooler, the precooling heat exchanger and the air cooling heat exchanger. A dehumidifying and drying device for compressed air, comprising: a refrigeration cycle that cools water that is circulated and supplied to the air compressor; and an oil cooler that cools lubricating oil of the air compressor.