JPS5824320A - Gas scrubber - Google Patents

Abstract

PURPOSE:To effectively recover a heat energy of washing water and to save energy, by providing a heat exchanger to a contacting part of the washing water and gas. CONSTITUTION:A multitube-type liq.-liq. heat exchanger 21 is arranged under a water spraying device 6 in a gas scrubbing tower 1. Washing water sprayed from the device 6, absorbs soluble components contained in a waste gas A exhausted from an air conditioning chamber and simultaneously is cooled by exchanging its heat with circulating water in the heat exchanger 21 while falling down onto the outer surfaces of the tubes of the heat exchanger 21, and then falls to a water receiving tank 8. After that, the washing water is sprayed again in the tower by a circulating pump 9. On the other hand, the cooled circulating water in the heat exchanger 21 is sent to a cooling coil 24 by a water circulating pump 22 and is returned again to the heat exchanger 21 through a pipe 23 after exchanging its heat with the outdoor air B. The air B is sent to the air conditioner after being precooled by the cooling coil 24.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas cleaning tower, and more particularly to a gas cleaning tower equipped with means for dispersing cleaning liquid within the tower.

Gas scrubbing towers are used, for example, for the purpose of cleaning gas discharged from an air-conditioned room, but conventional scrubbing towers of this type, as shown in FIG. A water receiving tank 8 provided below, a cleaning layer 5 (filling layer) provided in sequence above it, and a water sprinkling device 6. and a demister 7. An air intake port 2 is opened in the tower side wall at the bottom of the cleaning layer 5, and a blower 3 is installed upstream of the air intake port 2 on the air side. 4 is connected. Furthermore, the water receiving tank 8 is connected to the water sprinkler 6 via a cleaning liquid circulation pump 9 and a conveying pipe 10. In the gas scrubbing tower 1 configured in this way, the exhaust AH1 passes through the exhaust duct from the air-conditioned room, passes through the blower 3, and then flows into the gas scrubbing tower 1 from the air intake port 2. After that, the exhaust gas A is transferred to the cleaning layer 5
The gas is brought into countercurrent contact with the cleaning liquid sprayed from the water sprinkler 6, and soluble components in the gas are absorbed by the liquid. Thereafter, the gas from which the mist has been removed by the demister 7 is discharged to the outside air from the top of the tower.

However, in such conventional gas scrubbing towers, when the cleaning liquid comes into contact with the exhaust gas A, the cleaning liquid is cooled down to the temperature of the exhaust gas A, but the gas is not recovered at all. It wasn't.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a gas cleaning tower that can effectively recover the thermal energy of the cleaning liquid sprayed within the tower.

In order to achieve the above object, the present invention is characterized in that, in a gas cleaning tower that sprays a cleaning liquid from the upper part of the tower, a heat exchanger is provided at a contact area between the cleaning liquid and the gas to recover heat. More typically, the present invention provides a heat exchanger installed at the lower part of the water sprinkler of the gas scrubbing tower to perform gas scrubbing on the outer surface of the tubes of the heat exchanger, and at the same time, to clean the gas flowing inside the tubes of the heat exchanger. The structure is such that heat is exchanged between the washing liquid and the washing liquid.

Hereinafter, the present invention will be explained in more detail with reference to an embodiment shown in FIG.

2, the difference from the conventional example shown in FIG. 1 is that a liquid-liquid heat exchanger 2 is installed below the water sprinkler 6 in the gas scrubbing tower 1. This liquid-liquid heat exchanger 21 is a shell-and-tube heat exchanger connected to a cooling coil 24 via a water circulation pump 22 and a water conveying pipe 23. In such a configuration,
The cleaning liquid sprayed from the water spray device 6 absorbs soluble components in the gas while flowing down along the outer wall of the pipe of the liquid-liquid heat exchanger 21, and is cooled at the same time. For example, dry bulb temperature 26℃, 50%
Since the gas discharged from the room during RH has a wet bulb temperature of 18.7°C, the cleaning liquid is cooled to about 20°C by gas cleaning. While flowing down along the outer surface of the tube group of the heat exchanger 21, the cooled cleaning liquid exchanges heat with the circulating water in the heat exchanger and falls into the water receiving tank 8.

Thereafter, the cleaning liquid is returned to the water sprinkler 6 through the circulation pump 9 and the cleaning liquid conveying pipe 10, and is sprayed into the tower again. On the other hand, the circulating water cooled to around 21° C. by heat exchange in the liquid-liquid heat exchanger 21 is sent to the cooling coil 24 via the water conveying pipe 23 and the water circulation pump 22. After the circulating water exchanges heat with the outside air B in the cooling coil 24, it passes through the pipe 23 and is returned to the liquid-liquid heat exchanger 1°21. In addition, when the outside air B is 32°C in Q season and 60% RH, it is precooled to 26°C by a cooling coil and then sent to the air conditioner.

According to this embodiment, it is possible to perform gas cleaning and at the same time recover heat, which was conventionally attempted. For example, this recovered cold energy can be used to pre-cool outside air for air conditioning.

As described above, according to the present invention, it is possible to perform gas cleaning in the gas scrubbing tower and recover heat at the same time, thereby saving energy.

[Brief explanation of the drawing]

Figure 1 is a system diagram showing a conventional gas cleaning tower, and Figure 2 is a system diagram showing a conventional gas cleaning tower.
FIG. 1 is a system diagram of a gas scrubbing tower showing an embodiment of the present invention. ■... Gas cleaning tower, 6... Water sprinkler, 21.
-Liquid-liquid heat exchanger, 23...Water conveyance pipe, 24...Cooling coil, 25...Outside air intake duct. Figure 1 Figure 2

Claims (1)

[Scope of Claims] m. A gas cleaning tower in which a cleaning liquid is sprayed from the top of the tower, characterized in that a heat exchanger is provided at a contact area between the cleaning liquid and the gas to recover heat. (2. A gas cleaning tower according to claim 1, characterized in that the heat exchanger is mounted above the liquid-liquid heat exchanger and the cold heat of the cleaning liquid is recovered.