JPH08141568A - Apparatus for producing acid water - Google Patents

Abstract

PURPOSE: To stabilize pH of acid water produced from raw water even when it contains a larger quantity of hard water components, to reduce the cleaning operation of electrodes, and to extend the life of the electrodes. CONSTITUTION: A raw water supply pipe 2 for supplying raw water is connected to an electrolyzer 1 having an anode and a cathode which are separated by a diaphragm; an acid water discharge pipe 3 for taking out produced water and an alkaline water discharge pipe 4 are connected respectively to the anode side and the cathode side. A water softener for softening hard water components is installed in the raw water supply pipe 2, and a salt addition pipe 16 for adding sodium chloride is connected in the pipe 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acidic water producing apparatus for electrolyzing tap water or the like to produce acidic water.

[0002]

2. Description of the Related Art Acidic water used as washing or sterilizing water is produced by feeding raw water such as tap water into an electrolytic cell of an acidic water producing apparatus and electrolyzing it with electrodes provided in the electrolytic cell. At this time, it is known that the electrolytic cell for electrolyzing raw water is suitable for efficiently collecting acidic water on the anode side and alkaline water on the cathode side by partitioning the raw water into the anode side and the cathode side with a diaphragm. ing.

[0003]

However, in the above-mentioned conventional example, when the hard water component which is a cation, that is, the calcium ion or the magnesium ion is easily collected on the cathode side and the hard water component in the raw water is contained in a large amount. These hard water components are deposited on the cathode and adhere as a scale. If the scale of this hard water component adheres to the cathode, the electrical resistance between the electrodes will increase and the electrolysis capacity will decrease, making the pH of the acidic water produced unstable. Therefore, it is necessary to reverse the polarity of the electric power applied to the electrode to elute the attached scale in the raw water to wash the electrode. When the amount of hard water is large, the cleaning operation of the electrode needs to be performed frequently, which is troublesome, and even if the cleaning operation is repeated, it often remains and accumulates on the electrode, which shortens the life of the electrode. There is a tendency.

In view of the above points, the present invention stabilizes the pH of the acidic water to be produced even when a large amount of hard water component is contained in the raw water, and also minimizes the electrode cleaning operation. Furthermore, it aims at providing the acidic water manufacturing apparatus which extended the electrode life.

[0005]

In order to achieve the above object, the present invention connects a raw water supply pipe for supplying raw water to an electrolytic cell composed of an anode and a cathode separated by a diaphragm.
An acid water discharge pipe is connected to the anode side of the electrolytic cell, and a water softener for softening hard water components in raw water is interposed in the raw water supply pipe, and a salt water addition pipe for adding salt water to the raw water. It is characterized by connecting.

[0006]

According to the acidic water producing apparatus of the present invention, the raw water to be electrolyzed by the electrolyzer is passed through the water softener before being sent to the electrolyzer to remove calcium ions and magnesium ions in the raw water in the water softener. After that, it is sent to the electrolytic cell.
This makes it difficult for calcium ions and magnesium ions to deposit on the cathode during electrolysis, stabilizes the pH of the acidic water to be produced, requires less electrode cleaning due to reverse polarity, and extends the service life of the electrode.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a flow chart showing a processing flow of an acidic water producing apparatus, wherein 1 is an electrolytic cell having an anode and a cathode separated by a diaphragm, and the electrolytic cell 1 has raw water such as tap water. A raw water supply pipe 2 for supplying water, a discharge pipe for discharging generated water, an acid water discharge pipe 3 on the anode side, and an alkaline water discharge pipe 4 on the cathode side. Then, the heights of the outlets of the acidic water discharge pipe 3 and the alkaline water discharge pipe 4 are set to be the same so that the head pressures of the acidic water and the alkaline water with respect to the electrolytic cell 1 are equal, and the anode of the electrolytic cell 1 is The quality fluctuations such as PH are reduced by making the flows of the raw water flowing on the cathode side and the cathode side flow evenly without deviation.

In addition, a raw water supply valve 5 for starting and stopping the supply of raw water to the raw water supply pipe 2, a pressure reducing valve 6 for adjusting the water pressure of the raw water, and a signal from a flow sensor 7 for the raw water. A raw water flow rate control valve 8 for controlling the flow rate is arranged to adjust the flow rate of the raw water fed into the electrolytic cell 1.

Further, the raw water supply pipe 2 is provided with a water softener 9 for softening hard water. As shown in FIG. 2, the water softener 9 is filled with an ion exchange resin 11 in a main body container 10 and injected with raw water from a water injection port 12 at an upper portion thereof.
The layer is passed through to take out the lower soft water outlet 13.

The ion exchange resin 11 has a sodium ion in the ion exchange group of the resin body, and exchanges calcium ion and magnesium ion, which are hard water components in raw water, with sodium ion to soften the raw water. Then, when the sodium ion of the ion exchange resin 11 is reduced and the ion exchange performance is deteriorated, 10% saline solution as a regenerant solution is injected into the main body container through the regenerant solution injection pipe 14, and the ion is generated by sodium ion in the saline solution. The ion exchange resin 11 is regenerated by re-exchanging the calcium ion and the magnesium ion of the exchange resin 11.

Reference numeral 15 is a saline solution storage tank for storing saline solution for promoting electrolysis of raw water, and is adapted to store saline solution adjusted to an appropriate concentration of about 20%.
One end of a saline water addition pipe 16 is connected to the saline water storage tank 15, and the other end of the saline water addition pipe 16 is connected to the raw water supply pipe 2. Then, salt water is added after stabilizing the flow of raw water by the raw water flow control valve 8 and the like, and the addition amount can be adjusted by a flow rate adjusting valve 17 provided in a salt water adding pipe 16. .

Reference numeral 18 denotes a salt water diffusion tank arranged in the raw water supply pipe 2, in which raw water containing saline is injected from the lower part of the cylindrical main body, and while the main body is raised, the raw water is supplied by the water flow. The saline solution is diffused into the main body so as to overflow from the upper portion of the main body, and is disposed in front of the electrolytic cell 1. The saline diffusion tank 18 may be one that stirs the raw water with a circulation pump or a stirring blade, or may be a simple tank.

However, when the acidic water is produced by the acidic water producing apparatus, first, the pressure reducing valve 6 and the raw water flow rate control valve 8 are adjusted to adjust the respective control valves so that the desired flow rates are obtained.

Then, the raw water feed valve 5 is opened to start flowing the raw water through the raw water supply pipe 2. Raw water supply pipe 2
The raw water flowing through is first injected into the water softener 9. Water softener 9
Then, the filled ion exchange resin 11 exchanges calcium ions and magnesium ions, which are hard water components in the raw water, with sodium ions to be softened, and is sent out again to the raw water supply pipe 2.

For softened raw water, a pipe for salt solution addition 1
A saline solution having a predetermined concentration is added via 6 and the raw water containing this saline solution is then passed through the saline diffusion tank 18. The saline solution is further diffused in the raw water in the saline solution diffusion tank 18.

In this way, salt water having a predetermined concentration is added to the raw water from which calcium ions and magnesium ions have been removed, and the solution is homogenized by diffusion and fed into the electrolytic cell 1. In the electrolytic cell 1, a direct current voltage of a predetermined voltage is applied to the electrodes, acidic water collects at the anode and alkaline water collects at the cathode, and these generated water are discharged from the acidic water discharge pipe 3 and the alkaline water discharge pipe 4, respectively. Take it out.

At this time, if calcium ions or magnesium ions are contained in the raw water, they are deposited on the cathode to form scales, but since this apparatus is designed to remove calcium ions and magnesium ions in advance, these Will not be deposited as scale, or will be deposited to a slight extent if it cannot be removed.

Therefore, since scale hardly deposits on the cathode, so-called washing operation of frequently reversing the polarities of the electrodes to dissolve the deposits on the cathode is not required, and the acidic water can be stably produced for a long time. It can be performed.

[0020]

As described above, according to the acidic water producing apparatus of the present invention, the raw water supply pipe 2 for supplying the raw water to the electrolytic cell 1
Since the water softener 9 for softening the hard water component in the raw water is installed in the above, calcium ions and magnesium ions, which are the hard water components in the raw water, are removed before the raw water is sent to the electrolysis tank 1, and during the electrolysis of the raw water. The scale does not deposit due to calcium and magnesium ions on the cathode, the pH of the acidic water to be produced is stable, and acidic water can be produced without washing the cathode for a long time. The life can be extended.

[Brief description of drawings]

FIG. 1 is a flow chart showing an embodiment of the strongly acidic water producing apparatus of the present invention.

FIG. 2 is an explanatory diagram showing an internal structure of a water softener.

[Explanation of symbols]

1 ... Electrolyzer 2 ... Raw water supply pipe 3 ... Acidic water discharge pipe 4 ... Alkaline water discharge pipe 9 ... Water softener 16 ... Salt water addition pipe

Claims (1)

[Claims] 1. A raw water supply pipe for supplying raw water is connected to an electrolytic cell composed of an anode and a cathode separated by a diaphragm.
An acid water discharge pipe is connected to the anode side of the electrolytic cell, and a water softener for softening hard water components in raw water is interposed in the raw water supply pipe, and a salt water addition pipe for adding salt water to the raw water. The acidic water production apparatus is characterized in that