JP2920719B2 - High purity degassed water production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing high-purity degassed water by using a vacuum degasser to effectively degas volatile gases such as oxygen and carbon dioxide dissolved in a solution. About.

[0002]

2. Description of the Related Art Conventionally, as a deaeration method using a vacuum deaerator, for example, a method shown in a flow sheet of FIG. 2 has been known.

That is, industrial water heated above the operating temperature of the deaerator (1) is introduced into the deaerator (1) from the outside via the solution introducing pipe (2), and the solution introducing pipe (2) A spray nozzle (3) attached to the tip of the nozzle sprays the upper surface of the filling part (4) where the molding filler such as Raschig rings is clogged. The industrial water sprayed by the spray nozzle (3) in this manner becomes droplets, and at the same time, is heated to a temperature higher than the deaerator operating temperature. Most of the volatile gases such as oxygen are degassed.

Then, in order to perform a higher degree of deaeration, the stripping steam generated by the steam generator (11) is introduced from a stripping steam introduction pipe (7) below the deaerator (1). The residual volatile gas dissolved in the industrial water comes into gas-liquid contact with the stripping steam while the industrial water flows down the packing surface in the filling section (4), and most of the residual volatile gas is removed. I'm bothered.

[0005] The molded packing is supported by, for example, a grid-shaped packing support (9) so that it does not fall to the bottom of the deaerator. For example, a wire mesh-shaped filler retainer (10) is attached so that the filler does not break at the upper part of the deaerator (1) due to the rising force of the filler.

[0006] The deaerated water for industrial water degassed until the dissolved amount of the volatile gas is reduced to a very small amount in the deaerator (1).
Take it out of the deaerator (1) from the bottom with the take-out pipe (6). On the other hand, the vent gas (5) connected to the vacuum pump (12) is connected to the degassed volatile gas, the steam from flash evaporation, and the stripping steam rising from the filling section (4).
To the outside of the deaerator.

As another conventional method, a method using an inert gas such as N ₂ instead of using the stripping steam in the above is known.

[0008]

However, in such a method, the stripping steam generator (11) is used.
Also, it is necessary to install an inert gas supply device as ancillary equipment, which is uneconomical. In particular, a great deal of energy was required to generate stripping steam from water at room temperature.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a more economical and simple method for producing high-purity degassed water.

[0010]

That is, according to the method for producing high-purity degassed water of the present invention, raw water to be degassed is introduced into the upper part of the vacuum deaerator, and the degassed water accumulated at the bottom of the deaerator is removed. In the method for producing deaerated water taken out from the bottom of the deaerator, at least a part of the obtained deaerated water is heated to a temperature higher than the operating temperature in the deaerator, and the heated deaerated water is sprayed with a spray nozzle. use
And sprayed onto the lower portion of the deaerator, and is characterized in the use as stripping steam by flash evaporation in the deaerator.

In the present invention, the deaerator used may be of a conventionally known type, and includes a packed tower, a spray tower,
Alternatively, any of these combined types may be used.

It is preferable that the raw water to be degassed is heated to a temperature higher than the operating temperature in the deaerator before being introduced into the deaerator.

[0013]

The method of the present invention, as described above,
At least part of the water is higher than the operating temperature in the deaerator
Heat and strip the heated degassed water
Generator for stripping steam
Without installing as ancillary equipment, stripping water
Steam can be generated.

In the method of the present invention, at least a part of the obtained deaerated water is heated to a temperature higher than the operating temperature in the deaerator, and the heated deaerated water is used by using a spray nozzle.
Since then sprayed onto the lower portion of the deaerator, by flash evaporation in the deaerator is used as stripping steam, strike
The ripping effect is improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method of the present invention will be described with reference to the flow sheet of FIG. 1, but the present invention is not limited to this.

Referring to FIG. 1, a vacuum deaerator for carrying out the method of the present invention is configured as follows. That is, an introduction pipe (2) for introducing water to be degassed is provided above the deaerator (1), and a spray nozzle (3) is attached to a tip of the introduction pipe (2). At the center of the height of the deaerator (1), there is provided a filling section (4) filled with molding filling such as Raschig rings. The filling section (4) is supported by, for example, a grid-like filling support (9), and a wire mesh-like filling presser (10) is attached to the upper surface of the filling section. Deaerator
(1) At the bottom, a deaerated water outlet pipe (6) is provided.
In (6), a deaerated water pump (13) and a valve (16) are arranged, and in the valve (16), a deaerated water outlet pipe (17) and a deaerated water circulation pipe (8).
Is connected. A heater (14) is provided on the circulation pipe (8), and the circulation pipe (8) is guided to a lower part of the deaerator (1),
The spray nozzle (15) is attached to the tip. A vent pipe (5) connected to a vacuum pump (12) is provided at the top of the deaerator (1).

Using such a vacuum deaerator, a deaerator
(1) Operate at an internal temperature of 60 ° C. The industrial water to be degassed is heated to a temperature higher than 60 ° C, and this industrial water is introduced into the inlet pipe (2).
After that, it is introduced into the deaerator (1) and sprayed from the spray nozzle (3) onto the top of the filling section (4). The industrial water sprayed in this manner becomes droplets, and at the same time, is heated to a temperature higher than the operating temperature of the deaerator. Is largely degassed.

Then, the deaerated water collected at the bottom of the deaerator (1) is taken out from the outlet pipe (6), and a part of the deaerated water is removed by a deaerated water pump (13) and a valve (16). , Degassing water circulation pipe
Then, the degassed water is heated to 99 ° C. by the heater (14). The heated deaerated water is introduced into the lower part of the deaerator (1) through the spray nozzle (15). Heat deaerated water, deaerator (1)
Since the temperature is higher than the operating temperature in the inside, flash evaporation is performed to generate stripping steam. This stripping steam flows upward in the deaerator (1),
While the industrial water flows down the packing surface in the filling section (4),
In gas-liquid contact with industrial water, most of the remaining volatile gases in the industrial water are degassed. And finally the degassed water outlet pipe
Through (17), high-purity degassed water can be obtained. On the other hand, the degassed volatile gas and water vapor pass through the vent pipe (5) to the deaerator (1).
It is discharged out of the system.

In this embodiment, as described above, a part of the obtained deaerated water is heated to a temperature higher than the operating temperature in the deaerator (1) and introduced into the lower part of the deaerator. Since it is flash evaporated and used as stripping steam, stripping steam can be generated without using a stripping steam generator. Further, since the obtained degassed water to be circulated is about 60 ° C., when heated by the heater (14), it does not require the amount of heat required to heat water at room temperature, which is advantageous in terms of energy. It is.

[0020]

The method for producing degassed water of the present invention is configured as described above, so that stripping steam can be generated without installing an apparatus for generating stripping steam as an incidental facility. High-purity degassed water can be produced more economically. In addition, spray nose
Deaerated water sprayed on the lower part of the deaerator using
Flash evaporation in the vessel to make stripping steam
Used, the stripping effect is improved, and as a result
Effective degassing is possible, and high-purity degassed water
Obtainable.

[Brief description of the drawings]

FIG. 1 is a flow sheet illustrating the method of the present invention.

FIG. 2 is a flow sheet showing a conventional method.

[Explanation of symbols]

 (1)… Deaerator (2)… Introduction pipe (3)… Spray nozzle (4)… Filling part (5)… Vent pipe (6)… Extraction pipe (8)… Deaeration water circulation pipe (12)… Vacuum Pump (13)… Deaerated water pump (14)… Heating heater (15)… Spray nozzle (16)… Valve (17)… Deaerated water outlet pipe

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C02F 1/20 B01D 19/00

Claims (1)

(57) [Claims] The raw water to be degassed is introduced into the upper part of the vacuum deaerator (1), and the deaerated water collected at the bottom of the deaerator (1) is degassed.
(1) In the bottom take-out to degassed water manufacturing method, at least a portion of the degassed water resulting deaerator (1) by heating to warm to a temperature higher than the operating temperature in, degassed water this having been heated The spray
Using a nozzle (15) is sprayed into the lower portion of the deaerator (1) in, de
A method for producing high-purity degassed water , comprising flash-evaporating in a gasifier (1) to use as stripping steam.