JPH09899A - Apparatus for dissolving inert gas in material in liquid state - Google Patents

Abstract

PURPOSE: To make it possible to obtain a processing liquid which can remove oxygen (deoxidization) dissolved in water and various aqueous solutions by dissolving under a pressurized condition inert gas in the water and various aqueous solutions and can prevent oxygen from being redissolved in the water and various aqueous solutions from which the oxygen has been removed. CONSTITUTION: A supply passage 2 for water and various aqueous solutions to be processed and a discharge passage for a processing liquid are formed and a pressure vessel 4 is interposed between the supply passage 2 and the discharge passage 3, and an interior of the pressure vessel 4 is connected to communicate with a pressurized inert gas source 5 to allow inert gas to prevail in the interior of the pressure vessel 4, a liquid inlet hole for supplying the solutions to be processed and a discharge hole for discharging the processing solution allowed to fall into a bottom portion are opened to an upper portion of the interior of the pressure vessel 4, and a processing liquid pipe 3a communicating with the discharging hole is extended upward in order to be connected to the discharge passage 3. A dissolved oxygen detector 9 for detecting dissolved oxygen in the processing liquid is disposed in the discharge passage 3, and detectors 7a, 7b for detecting the liquid level of the processing liquid retained in the bottom portion, an exhaust valve 5c for discharging gas in the interior of the pressure vessel 4 and a supply regulating valve 5b for regulating the supply of the inert gas are arranged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention removes (deoxygenates) dissolved oxygen in water such as industrial water and drinking water and various aqueous solutions, and prevents re-dissolution of oxygen in a deoxidized treatment liquid. The present invention relates to an apparatus for dissolving an inert gas in a liquid material, which is capable of obtaining a treatment liquid.

[0002]

2. Description of the Related Art As a deoxidizing method for removing dissolved oxygen in water such as industrial water and drinking water and various aqueous solutions, conventionally, a treatment liquid is depressurized by a vacuum pump and degassed by utilizing a boiling point decrease due to the depressurization. Method, method for heating and boiling treatment liquid to degas, method for increasing degassing efficiency by using the above and methods together, passing treatment liquid through separation membrane module, and removing gas molecules by separation membrane Method,
There is a method in which a deoxidizing agent (reducing agent) such as sodium sulfite, hydrazine, and tannin is added and removed by a chemical reaction with dissolved oxygen.

[0003]

However, in the above methods (1) to (4), the degassed treatment liquid promotes the redissolution of oxygen in the air and maintains the deoxidized state when exposed to the atmosphere. Difficult to use, and needs to be shut off from the air. In the method,
The size of the processing device becomes large and the cost becomes high. The method (1) has the same problems as described above, and also has the problem of causing a residual drug.

Therefore, according to the present invention, dissolved oxygen in the liquid is removed (deoxygenated) by dissolving an inert gas in water or various aqueous solutions under pressure, and the dissolved oxygen is added to the treated liquid. It is an object of the present invention to provide an apparatus for dissolving an inert gas in a liquid material, which is capable of obtaining a treatment liquid capable of preventing redissolution of oxygen.

[0005]

In order to solve the above problems, an apparatus for dissolving an inert gas in a liquid material according to the present invention is provided with a supply path for a liquid to be processed such as water or various aqueous solutions and a discharge path for the processing liquid. And a pressure-resistant container interposed between the supply passage and the discharge passage, and the inside of the pressure-resistant container is connected to a pressurized inert gas source to create an inert gas atmosphere, The inlet for supplying the liquid to be treated to the top and the outlet for discharging the treatment liquid dropped to the bottom are opened, the treatment liquid pipe continuous to the outlet is extended upward and connected to the discharge path, and the discharge is performed. A detector for detecting the dissolved oxygen amount of the processing liquid is provided in the passage, and a detector for detecting the liquid level of the processing liquid accumulated at the bottom, an exhaust valve for discharging the gas in the pressure vessel, and the supply of the inert gas are adjusted. It is characterized in that a supply control valve is provided.

Further, in a preferred aspect of the present invention, a plurality of diffusion plates can be provided in the pressure vessel. In another preferred aspect of the present invention, a check valve may be provided in the liquid supply pipe connected to the liquid inlet and supplying the liquid to be treated to the uppermost portion of the pressure vessel.

[0007]

The liquid to be treated is introduced into the pressure resistant container 4 interposed between the supply passage and the discharge passage. The liquid to be treated drops in a drop shape from a liquid inlet opening in the upper part of the pressure-resistant container, comes into contact with an inert gas filling the container, absorbs it, and simultaneously releases dissolved oxygen. The processing liquid that has absorbed the inert gas and dropped to the bottom is collected at the bottom in the pressure resistant container, receives the discharge pressure of the supply pump provided in the supply path, and ascends the processing liquid pipe 3a connected to the discharge port to be discharged to the outside. To be done. The magnitude of the pressure acting on the bottom liquid is controlled by the valve 13 provided in the discharge passage. Then, the dissolved oxygen amount detector provided in the discharge passage detects the amount of dissolved oxygen in the treatment liquid, and when the amount exceeds the set value, the inert gas in the pressure vessel is replaced.

Further, a plurality of diffusion plates provided in the pressure-resistant container diffuses the liquid to be treated falling from the liquid inlet opening in the upper part of the container into the container to increase the contact area with the inert gas. It improves the efficiency of absorbing inert gas and the efficiency of releasing dissolved oxygen. The check valve provided in the liquid supply pipe prevents, for example, backflow of the liquid to be treated when the supply pump is stopped, and the inert gas in the pressure resistant container flows back through the liquid supply pipe and escapes to the outside. Prevent.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. The inert gas dissolving device 1 includes a pressure resistant container 4 interposed between a liquid supply path 2 (liquid supply pipe 2a) and a discharge path 3 (processing liquid pipe 3a) for a liquid to be processed, and an inert gas to the pressure resistant container 4. And an inert gas supply source 5 for supplying. In this embodiment, the inert gas supply source 5 is a high pressure nitrogen gas cylinder. The inert gas supply source 5 is not limited to nitrogen gas, and may be argon, helium, or the like. Reference numeral 6 is a supply pump for the liquid to be treated provided on the liquid supply pipe.

The pressure-resistant container 4 is formed in a vertical cylindrical shape by a corrosion-resistant material such as stainless steel or hard synthetic resin which is difficult to oxidize. Of course, it does not exclude an inexpensive container made of a steel plate and used by applying corrosion-resistant coating or plating. Pressure container 4
In the upper part of the tank, a nitrogen gas cylinder and other inert gas source 5
Of the inert gas pipe 5a, the liquid supply pipe 2a forming the supply passage, and the processing liquid pipe 3a forming the discharge passage.
Is connected.

A supply control valve 5b is provided on the inert gas pipe 5a.
And an exhaust valve 5c. These valves 5b and 5c
Consists of a solenoid valve. The liquid level sensors 7a, 7a are provided at predetermined upper and lower positions on the outer surface of the side wall of the pressure vessel 4.
b, a valve 8 is provided in the treatment liquid pipe 3a, and a dissolved oxygen amount detection sensor 9 is provided downstream thereof. At the start of the operation, the liquid to be treated is fed into the pressure resistant container 4 by the supply pump 6 to fill the inside of the container to remove air from the container. Next, exhaust valve 5
When the supply control valve 5b is opened with c closed and the inert gas is supplied into the container, the liquid level drops, and when the lower liquid level sensor 7b detects the liquid level, the supply control valve 5b is closed to perform normal operation. Become. The opening of the valve 8 is adjusted so that the pressure inside the pressure vessel 4 is about 0.3 to 3 kgf / cm ² (gauge pressure) depending on the purpose. According to Henry Doleton's law, the higher the pressure, the more the amount of the inert gas dissolved in the treatment liquid increases and the amount of dissolved oxygen decreases. In addition, 5d is a pressure gauge for displaying the pressure in the pressure vessel 4, and 10 is a drain valve for removing drainage and sludge provided near the bottom of the pressure vessel 4, and the valve is normally closed. Reference numeral 11 is a viewing window for confirming the inside of the pressure resistant container, and 12 is an opening / closing lid for cleaning for cleaning the inside of the pressure resistant container.

Next, the internal structure of the pressure vessel 4 will be described with reference to FIG. A diffusion plate 13 is provided in the upper part of the pressure-resistant container 4, and the inside is divided into upper and lower parts. A liquid inlet opening to the liquid supply pipe 2a is opened above the diffusion plate 13, and the liquid to be treated sent by the supply pump 6 through the liquid supply pipe 2a is discharged to the upper surface of the diffusion plate 13. Diffuser 1
3 has a large number of holes 13a formed therein, and the liquid discharged onto the upper surface of the diffusion plate 13 travels along the edge of the hole 13a and becomes an infinite number of drops, which are dripped downward.

The liquid to be treated dropped from the diffusing plate 13 absorbs the inert gas forming the atmosphere, releases the dissolved oxygen in the liquid, and drops to the bottom. That is, since the liquid falling by gravity from the diffusion plate 13 is in the form of drops or particles and has an increased surface area, the chances of contact with the inert gas forming the atmosphere are increased, and the pressure vessel 4 is higher than atmospheric pressure. Since the atmosphere is an inert gas atmosphere, absorption of the inert gas and release of dissolved oxygen are further promoted. In addition, this diffusion plate 1
Although 3 is fixedly installed on the inner surface of the pressure-resistant container 4, it may be in the shape of a rotating wing. Thereby, the liquid to be treated can be further miniaturized, and the surface area of the liquid may be further increased. In addition, instead of the diffusion plate 13, or together with the diffusion plate 13, a nozzle or a sprayer may be provided at the opening of the liquid supply pipe 2a. As described above, by providing the diffusion plate, the treatment liquid collides with the diffusion plate and bounces back due to the difference in height between the liquid inlet opening to the liquid supply pipe 2a and the diffusion plate, thereby increasing the fall distance of the treatment liquid. be able to. If the diffusion plates 13 and 13 'are installed in a plurality of stages of diffusion plates, for example, as shown in FIG. Since it is possible to further promote atomization of the liquid droplets by the collision with, it is possible to further improve the inert gas absorption efficiency and the dissolved oxygen release efficiency. In addition, in order to obtain such an effect,
Make sure that the positions of the multiple holes 13a formed in the diffusing plates 13 and 13 'provided in the step are not the same as those of the upper diffusing plate and that of the lower diffusing plate, and Make the dropped droplets collide with the lower diffusion plate. The diffusion plates 13 and 13 'are attached to the pressure resistant container by the support rod 13b.

In this way, the processing liquid that has dropped to the bottom of the pressure-resistant container 4 is pushed by the pressure from the supply pump 6 into the lower end of the processing liquid pipe 3a that forms the discharge port, rises and overflows to the outside, It flows into the discharge path 3.

During the above treatment, as the dissolved oxygen is released from the treatment liquid, the oxygen gas concentration (oxygen gas partial pressure) in the pressure vessel 4 rises, and the deoxygenating ability decreases accordingly. Therefore, the upper limit of the dissolved oxygen amount in the treatment liquid is appropriately set according to the purpose (for example, 0.5 ppm), and the dissolved oxygen amount detection sensor 9 provided in the treatment liquid pipe detects the dissolved oxygen amount in the treatment liquid, When the set value is exceeded, the exhaust valve 5c is opened to exhaust the gas in the pressure resistant container 4. Then, the liquid level starts rising, and when the upper liquid level sensor 7a detects the liquid level, the exhaust valve 5c is closed, and at the same time, the supply control valve 5b is opened to supply the inert gas into the pressure resistant container 4. Then, the liquid level starts to descend, and when the lower liquid level sensor 7b detects the liquid level, the supply control valve 5b is closed. By repeating this operation, gas exchange between the dissolved oxygen and the inert gas in the treatment liquid is continuously performed. The various controls described above are performed via the control unit 14.

If the check valve 15 is provided in the liquid supply pipe 2a, the processing liquid flows back when the supply pump 6 is stopped, for example, so that the inert gas in the pressure resistant container 4 is supplied with the inert gas. It is preferable because it can be prevented from flowing backward and flowing out.

Since the deoxidation treatment is performed under the pressure of the inert gas, the concentration of the inert gas in the treatment liquid is saturated under the pressure. When such a treatment liquid is exposed to the atmosphere, the concentration of the inert gas in the treatment liquid is high, so that re-dissolution of oxygen gas in the atmosphere is prevented, and as a result, the deoxidized state can be maintained for a long time.

The deoxidizing performance can be improved by connecting a plurality of such treatment devices in series with two or three treatment devices with or without a storage tank.

The liquid to be treated is boiler water,
Cooling water for cooling equipment, water for cleaning electronic parts and semiconductors, metal processing, surface treatment, iron, pulp, chemical processing, etc., various processing water, food processing, chemical manufacturing, brewing, sugar manufacturing, etc. It covers all industrial fields such as drinking water for water tanks and water tanks for general waterworks, and cooling water for computers and high-tech equipment.

According to the treatment liquid treated using this apparatus, the corrosion prevention and scale formation prevention of the storage tank and the piping equipment associated with the oxidation reaction due to dissolved oxygen, which has been a problem in the past, and the scale decomposition, and the oxidative decomposition during the preservation of the treatment liquid are carried out. It is possible to maintain the quality characteristics of the processing liquid such as alteration prevention and prevent deterioration.

[0021]

According to the apparatus of the present invention, since the liquid to be processed is only processed in a pressurized inert gas atmosphere, the liquid can be processed without being affected by the type or property of the liquid to be processed. Also,
Regardless of the temperature condition of the liquid to be treated, there is no need to heat or administer a drug, so that the treatment liquid is not deteriorated or decomposed. Since the deoxidation treatment is performed under the pressure of the inert gas, the concentration of the inert gas in the treatment liquid is saturated under the pressure. When such a treatment liquid is exposed to the atmosphere, the concentration of the inert gas in the treatment liquid is in a supersaturated state, which hinders the re-dissolution of oxygen gas in the atmosphere, and the inert gas that is gradually degassed is air. It acts as a barrier to the oxygen in it, and as a result, it can maintain the deoxidized state for a long time.

[Brief description of drawings]

FIG. 1 is an external view of a pressure resistant container.

FIG. 2 is an external view corresponding to FIG. 2 with a part thereof broken away.

FIG. 3 is an external view showing a pressure-resistant container according to another embodiment of the present invention with a part thereof cut away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inert gas dissolving device 2 Supply path 2a Liquid supply pipe 3 Discharge path 3a Process liquid pipe 4 Pressure vessel 5 Inert gas supply source 5a Inert gas pipe 5b Supply control valve 5c Exhaust valve 6 Supply pump 7a, 7b Liquid level sensor 8 Valve 9 Dissolved oxygen amount detection sensor 13, 13 'Diffusion plate 15 Check valve

Claims (3)

[Claims] 1. A supply passage for a liquid to be treated such as water or various aqueous solutions and a discharge passage for a treatment liquid are provided, and a pressure container is interposed between the supply passage and the discharge passage, and the inside of the pressure container is pressurized. The inside of the pressure resistant container is connected to the above-mentioned inert gas source to create an inert gas atmosphere, and the inlet for supplying the liquid to be processed is opened at the upper part of the pressure vessel and the outlet for discharging the liquid to be processed dropped to the bottom is opened. Detecting the level of the processing liquid accumulated at the bottom, while the processing liquid pipe continuous to the discharge port is extended upward and connected to the discharge path, the dissolved oxygen amount detector for the processing liquid is provided in the discharge path. A device for dissolving an inert gas in a liquid material, which is provided with a container, an exhaust valve for discharging the gas in the pressure resistant container, and a supply control valve for controlling the supply of the inert gas. 2. The apparatus for dissolving an inert gas in a liquid according to claim 1, wherein a plurality of diffusion plates are provided in the pressure vessel. 3. The check valve is provided in a liquid supply pipe which is connected to the liquid inlet and supplies a liquid to be treated to an uppermost portion in the pressure resistant container. Inert gas dissolving device for liquid substances.