JP2006015238A - Water treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment apparatus in which chlorine gas generated by electrolysis can be utilized for producing residual chlorine in higher efficiency. <P>SOLUTION: This water treatment apparatus 1 is constituted so that the water which is to be treated and is housed in an electrolytic cell 10 is electrolyzed to convert a chloride ion in the water to be treated into chlorine gas and the obtained chlorine gas is neutralized to produce hypochlorous acid. The chlorine gas-containing vapor in the electrolytic cell 10 is sent to a trap 60 by a fan 40 and condensed in the trap 60. In other words, the chlorine gas in the vapor is neutralized in the trap 60 and converted into hypochlorous acid. A solution in the trap 60 is introduced into the electrolytic cell 10 through a pipeline 51. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water treatment apparatus, and more particularly, to a water treatment apparatus that immerses an electrode pair in water to be treated and converts the water to be treated into electrolyzed water containing a desired component by an electrolytic reaction using the electrode pair.

  Residual chlorine has been used for sterilization and deodorization of tap water, pool water, and bath water in public baths. It has also been known for a long time that chlorine ions contained in fresh water can be converted into residual chlorine by electrolysis.

  For example, Patent Document 1 discloses a technique for performing sterilization by introducing water to be treated stored in a water tank into an electrolytic tank and subjecting the water to be treated to electrolytic treatment. Here, by subjecting the water to be treated to electrolytic treatment, chloride ions in the water to be treated are oxidized into chlorine gas, and residual chlorine (subsequently generated by hydration of the chlorine gas) Sterilization is performed with various substances including chlorous acid and hypochlorite ions.

Further, in Patent Document 2, an electrolytic cell is provided integrally with a water flow block having a passage through which dilution raw water passes, and chlorine gas generated by electrolysis in the electrolytic cell is combined with the dilution raw water through the water flow block. The technique to make it disclose is disclosed.
JP 2001-232364 A JP-A-6-99174

  Conventionally, such a water treatment apparatus has been required to generate a sterilizing substance such as hypochlorous acid generated based on electrolytic treatment with high efficiency.

  However, in the technique described in Patent Document 1, chlorine gas generated by electrolysis may be released outside the electrolytic cell as a gas without being absorbed by the water to be treated. For this reason, the technique described in Patent Document 1 needs to be further considered in terms of improving the generation efficiency of substances produced from chlorine gas generated by electrolysis, such as hypochlorous acid. It is thought that.

  In the technique described in Patent Document 2, the chlorine gas contained in the vapor during the electrolytic treatment can be sufficiently used for the generation of residual chlorine, but remains in the treated water subjected to the electrolytic treatment, and the above-described communication is performed. From the viewpoint of fully utilizing the chlorine gas that cannot reach the water block and the residual chlorine generated based on the chlorine gas, it is considered that another consideration is necessary.

  The present invention has been conceived in view of such circumstances, and its purpose is to make it possible to use chlorine gas generated by electrolysis in a water treatment apparatus with higher efficiency for the generation of residual chlorine. is there.

  A water treatment apparatus according to the present invention is a water treatment apparatus that generates residual chlorine, an electrolytic cell that contains water to be treated, an electrode pair that is accommodated in the electrolytic cell, and power supply to the electrode pair And a trap provided outside the electrolytic cell for condensing vapor generated in the electrolytic cell.

  Moreover, it is preferable that the water treatment apparatus according to the present invention further includes a forwarding means for returning the solution condensed in the trap to the electrolytic cell.

  Further, the water treatment apparatus according to the present invention comprises a residual chlorine concentration detection means for detecting a residual chlorine concentration of the solution in the trap, a storage means for storing a threshold value of the residual chlorine concentration relating to the solution in the trap, Supply means for supplying an alkaline substance into the electrolytic cell, and the supply so that the alkaline substance is supplied to the electrolytic tank when the residual chlorine concentration detected by the residual chlorine concentration detection means exceeds the threshold value It is preferable to further comprise control means for controlling the means.

  Further, the water treatment apparatus according to the present invention further comprises pH detection means for detecting the pH value of the water to be treated accommodated in the electrolytic cell, and the control means detects the pH value detected by the pH detection means. It is preferable that the alkaline substance is supplied to the supply means when the value is lower than a predetermined value.

  In the water treatment apparatus according to the present invention, the trap preferably includes a nonwoven fabric.

  Moreover, in the water treatment apparatus according to the present invention, the trap further includes an introduction port through which steam generated in the electrolytic cell is introduced, and the nonwoven fabric is installed above the introduction port in the trap. It is preferred that

  Moreover, it is preferable that the water treatment apparatus according to the present invention further includes a fan that sends steam in the electrolytic cell to the trap.

  According to the present invention, the water to be treated in the electrolytic cell is subjected to the electrolytic treatment using the electrode pair, thereby generating chlorine gas, and the chlorine gas is hydrated to the water to be treated. Thus, residual chlorine such as hypochlorous acid is generated. Even when the generated chlorine gas becomes vapor in the electrolytic cell, the vapor is condensed in the trap. Thereby, the chlorine gas contained in the vapor can also be hydrated and captured in the solution in the trap.

  Therefore, according to the present invention, the chlorine gas generated by electricity can be used for generating residual chlorine with high efficiency.

  Moreover, according to this invention, the solution condensed by the trap can be handled together with the water to be treated in the electrolytic cell.

  In addition, according to the present invention, the amount of chlorine gas contained in the solution can be predicted from the residual chlorine concentration of the solution condensed in the trap, whereby the pH value of the steam and water to be treated in the electrolytic cell can be estimated. Since it can consider, the pH value of the to-be-processed water in an electrolytic vessel can be adjusted based on the result considered about the said pH value. That is, even when electrolysis is performed in the electrolytic cell and it may be difficult to detect the pH value of the water to be treated by a pH meter installed in the electrolytic cell, the pH value of the water to be treated is surely obtained. Can be adjusted.

  Moreover, according to this invention, based on the value which the pH detection means installed in the electrolytic cell detects, adjustment of the pH value of the to-be-processed water in the said electrolytic cell is attained. Therefore, the pH value of the water to be treated in the electrolytic cell can be adjusted more reliably.

  Moreover, according to this invention, a vapor | steam can be efficiently condensed with a nonwoven fabric in a trap.

  Moreover, according to this invention, the vapor | steam generate | occur | produced in the electrolytic cell can be efficiently sent to a trap, Thereby, the said vapor | steam can be condensed efficiently.

  Hereinafter, embodiments of a water treatment apparatus of the present invention will be described with reference to the drawings. The parts denoted by the same reference numerals throughout the drawings have the same effects unless otherwise specified, and will not be described repeatedly.

  FIG. 1 is a diagram schematically showing a configuration of a water treatment apparatus according to an embodiment of the present invention, and FIG. 2 is a control block diagram of the water treatment apparatus.

  With reference to FIG. 1 and FIG. 2, the water treatment apparatus 1 mainly includes an electrolytic cell 10 that stores water to be treated, and a control unit 20 that controls the operation of the water treatment apparatus 1 as a whole. Including.

  The electrolytic cell 10 is connected to a pipe to which the water supply pump 101 and the water supply valve 102 are connected, and is connected to a pipe to which the drainage pump 111 and the drainage valve 112 are connected. In the water treatment apparatus 1, the water supply valve 102 is opened and the water supply pump 101 is turned on, whereby water to be treated is introduced into the electrolytic cell 10, the drainage valve 112 is opened, and the drainage pump 111 is turned on. As a result, the water to be treated in the electrolytic cell 10 is discharged to a suitable place.

  An intake hole 10 </ b> A is formed at the upper end of the electrolytic cell 10, and one ends of the pipe 50 and the pipe 51 are connected. The other end of the pipe 50 is connected to the trap 60. A fan 40 is attached to the pipe 50. The steam in the electrolytic cell 10 is sent to the fan 40 and introduced into the trap 60 through the pipe 50. The trap 60 is formed with an inlet 60A, an overflow port 60B, and an exhaust hole 60C, and the steam in the pipe 50 is introduced into the trap 60 through the inlet 60A.

  A non-woven fabric 70 for trapping steam is installed in the trap 60 above the inlet 60A. A residual chlorine concentration sensor 80 is installed in the trap 60. One end of the pipe 51 is connected to the overflow port 60 </ b> B of the trap 60. The other end of the pipe 51 is connected to the upper part of the electrolytic cell 10. The solution in the trap 60 passes through the overflow port 60 </ b> B and is sent to the electrolytic cell 10 through the pipe 51. Further, when the pressure in the trap 60 increases, the gas is appropriately discharged through the exhaust hole 60C.

  The electrolytic cell 10 further includes a pH meter 90 for detecting the pH value of the water to be treated introduced into the electrolytic cell 10, an electrode pair 11 including an anode electrode and a cathode electrode, A water level sensor 12 for detecting whether or not the water level of the water to be treated has reached a water level suitable for electrolytic treatment (hereinafter referred to as “predetermined water level”) is installed. In addition, the electrode pair 11 installed in the electrolytic cell 10 may be one pair or a plurality of pairs.

  The water treatment apparatus 1 is attached to a pH adjuster tank 30 that stores a substance (pH adjuster) that supplies the electrolytic cell 10 and adjusts the pH of the water to be treated, and the pH adjuster tank 30. The pH adjusting agent pump 31 for sending the pH adjusting agent stored in the pH adjusting agent tank 30 to the electrolytic cell 10 and the power supply circuit 21 for supplying power to the electrode pair 11 are provided. The electrode pair 11 is supplied with electric power to cause a current to flow between the anode electrode and the cathode electrode in the water to be treated. The power supply circuit 21 is for controlling how power supplied from an external power supply is supplied to the electrode pair 11.

  The control unit 20 controls the operation of the water treatment device 1 as a whole. Specifically, the control unit 20 receives detection outputs from the water level sensor 12, the residual chlorine concentration sensor 80, and the pH meter 90. The control unit 20 controls operations of the power supply circuit 21, the fan 40, the water supply pump 101, the water supply valve 102, the drainage pump 111, the drainage valve 112, and the pH adjuster pump 31. In addition, the control unit 20 includes a memory 20A that stores various data.

  Here, an example of a chemical reaction predicted when a current flows between the anode electrode and the cathode electrode of the electrode pair 11 in the electrolytic cell 10 will be described.

  In the water to be treated in the electrolytic cell 10, oxygen gas is generated in the vicinity of the anode electrode by water electrolysis as shown in the formula (1).

2H ₂ O⇔O ₂ ↑ + 4H ⁺ + 4e ⁻ (1)
Further, chloride ions contained in the water to be treated in the electrolytic cell 10 become chlorine gas in the vicinity of the anode electrode as shown in the formula (2), and a part of the generated chlorine gas is expressed by the formula (3). Hydrated to hypochlorous acid as shown in FIG.

2Cl ⁻ ＣｌCl ₂ ↑ + 2e ⁻ (2)
Cl ₂ + H ₂ O⇔H ⁺ + Cl ⁻ + HClO (3)
Next, regarding the operation of the water treatment apparatus 1 when the water to be treated introduced into the electrolytic cell 10 of the water treatment apparatus 1 is subjected to the electrolytic treatment, the electrolytic control executed by the control unit 20 during the electrolytic treatment. Further detailed description will be given with reference to FIG. 3 which is a flowchart of the processing.

  In the electrolysis control process, the control unit 20 first opens the water supply valve 102 and turns on (drives) the water supply pump 101 in step S1 (hereinafter, simply referred to as “S1”, omitting “step”). As a result, the water to be treated is introduced into the electrolytic cell 10.

  Next, in S <b> 2, the control unit 20 determines whether or not the water level sensor 12 has detected that the water to be treated has been introduced to the predetermined water level in the electrolytic cell 10. And if it judges that the water level sensor 12 detected having reached the above-mentioned predetermined water level, the control part 20 will advance a process to S3.

  In S <b> 3, the controller 20 stops the water supply pump 101 and closes the water supply valve 102.

  Next, in S <b> 4, the control unit 20 starts electrolysis in the electrolytic cell 10 by causing the power supply circuit 21 to pass a current between the anode electrode and the cathode electrode of the electrode pair 11. The value of current that flows between the anode electrode and the cathode electrode is appropriately determined according to the amount and quality of the water to be treated introduced into the electrolytic cell 10.

  Next, the controller 20 turns on the fan 40 in S5. Thereby, the steam in the electrolytic cell 10 is efficiently introduced into the trap 60.

  Next, the control unit 20 determines whether or not a predetermined electrolysis time has elapsed in S6. The control unit 20 includes a timer (not shown). In S6, the control unit 20 makes a determination by referring to the time measured by the timer. The predetermined electrolysis time is a time that is considered necessary for converting chloride ions in the water to be treated introduced into the electrolytic cell 10 into residual chlorine such as hypochlorous acid and hypochlorite ions, The time is appropriately determined based on the predetermined amount and the quality of the water to be treated introduced into the electrolytic cell 10. When the control unit 20 determines that the predetermined electrolysis time has not yet elapsed, the control unit 20 proceeds to S7, and when it determines that the predetermined time has elapsed, the control unit 20 proceeds to S9.

  In S <b> 7, the control unit 20 determines whether or not the detection output of the residual chlorine concentration sensor 80 in the trap 60 exceeds a predetermined threshold value. When the controller 20 determines that it has exceeded, the pH adjusting agent pump 31 is driven in S8 to introduce the pH adjusting agent in the pH adjusting agent tank 30 into the electrolytic cell 10, and in S6. Return processing.

  In the present embodiment, when the residual chlorine concentration of the solution in the trap 60 is increased to some extent by the processing of S7 to S8, the pH adjuster is supplied to the electrolytic cell 10. In the present embodiment, the pH adjuster is a substance for making the water to be treated in the electrolytic cell 10 alkaline.

  In addition, it is thought that pH of the to-be-processed water in the electrolytic vessel 10 is so low that the residual chlorine concentration of the solution in the trap 60 is high. This is because it is considered that the chlorine gas contained in the vapor in the electrolytic cell 10 increases as the acidity of the water to be treated in the electrolytic cell 10 increases.

Further, from the above formula (3), when the pH of the water to be treated is lowered in the electrolytic cell 10, the reaction of generating chlorine gas from hypochlorous acid, which is the reverse reaction of the reaction of generating hypochlorous acid. Is likely to occur. This is because there is “H ⁺ ” on the left side of Equation (3).

  Therefore, in the present embodiment, control is performed so that residual chlorine such as hypochlorous acid is easily generated by appropriately supplying a pH adjuster to the electrolytic cell 10 based on the residual chlorine concentration in the trap 60. Will be done. The above-mentioned threshold is preliminarily set as a residual chlorine concentration value of the solution in the trap 60 corresponding to the pH value of the water to be treated in the electrolytic cell 10 where residual chlorine is likely to be generated based on the composition of the water to be treated. For example, this value is stored in the memory 20A.

  On the other hand, in S <b> 9, the control unit 20 causes the power supply circuit 21 to stop energization between the anode electrode and the cathode electrode of the electrode pair 11.

  Next, in S10, the control unit 20 turns off the fan 40 and stops the operation of the fan 40.

  Next, in S11, the control unit 20 opens the drain valve 112 and turns on (drives) the drain pump 111. As a result, the water to be treated is discharged from the electrolytic cell 10.

  Next, in S12, the control unit 20 determines whether or not a predetermined drainage time has elapsed since the drainage valve 112 was opened. The predetermined drainage time is the time required for all of the treated water introduced into the electrolytic cell 10 to flow out of the electrolytic cell 10 through the drainage port. The capacity of the electrolytic cell 10 and the drainage port It is a time that is appropriately determined based on the diameter and the like. Then, when determining that the predetermined drainage time has elapsed, the control unit 20 stops the drainage pump 111, closes the drainage valve 112, and returns the process to S1.

  In the present embodiment described above, by subjecting the water to be treated accommodated in the electrolytic cell 10 to electrolytic treatment, chloride ions in the water to be treated are made chlorine gas, and further, the chlorine gas is water. Hypochlorous acid is formed in the sum. Note that the vapor in the electrolytic cell 10 is sent to the trap 60 by the fan 40. Thereby, the vapor | steam containing the chlorine gas in the electrolytic cell 10 is condensed in the trap 60. FIG. Therefore, the chlorine gas in the steam is hydrated in the trap 60 and becomes hypochlorous acid. The solution in the trap 60 is guided to the electrolytic cell 10 through the pipe 51.

  In the present embodiment described above, a predetermined amount of water to be treated is introduced into the electrolytic cell 10, and after a predetermined amount of water to be treated in the electrolytic cell 10 is subjected to electrolytic treatment, The water to be treated in the electrolytic bath 10 is replaced and the next electrolytic treatment is performed. That is, in the present embodiment, the electrolytic treatment is performed in the electrolytic cell 10 by a so-called batch processing method.

  However, the present invention is not limited to the one in which the electrolytic treatment for the water to be treated is performed in such a batch treatment method, and any water treatment apparatus that performs the electrolytic treatment for the water to be treated itself may be used in all cases. Can be applied.

  Moreover, in this Embodiment demonstrated above, the pH value of the to-be-processed water in the electrolytic cell 10 is estimated from the residual chlorine concentration of the solution in the trap 60, and pH adjustment is carried out to the electrolytic cell 10 based on the said prediction result. It was decided whether to supply the agent.

  The present invention is not limited to such a supply mode. That is, for example, the detection output of the pH meter 90 installed in the electrolytic cell 10 may be directly used, and based on the detection output, it may be determined whether or not to supply the pH adjuster to the electrolytic cell 10. That is, the control unit 20 may be configured to supply the pH adjuster to the electrolytic cell 10 when the pH value detected by the pH meter 90 is less than a predetermined value. Note that the “predetermined value” in such a case can also be stored in the memory 20A, for example.

  Further, whether or not to supply the pH adjusting agent to the electrolytic cell 10 may be determined based on both the detection output of the residual chlorine concentration sensor 80 and the detection output of the pH meter 90. That is, the control unit 20 adds a pH adjuster to the electrolytic cell 10 when the residual chlorine concentration exceeds the threshold value and the pH value of the water to be treated in the electrolytic cell 10 is less than the predetermined value. It may be configured to supply.

  In addition, the amount of the pH adjusting agent supplied to the electrolytic cell 10 by one processing in S8 can be a predetermined amount, the residual chlorine concentration detected by the residual chlorine concentration sensor 80, and the threshold value described above. It may be changed according to the difference.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows typically the structure of the water treatment apparatus which is one embodiment of this invention. It is a control block diagram of the water treatment apparatus of FIG. It is a flowchart of the electrolysis control process which a control part performs in the case of the electrolysis process with respect to the to-be-processed water introduced in the electrolytic vessel of the water treatment apparatus of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Water treatment apparatus, 10 Electrolyzer, 10A Intake hole, 11 Electrode pair, 12 Water level sensor, 20 Control part, 20A Memory, 21 Power supply circuit, 30 pH adjuster tank, 31 pH adjustment pump, 40 Fan, 50, 51 Piping, 60 trap, 60A introduction port, 60B overflow port, 60C exhaust port, 70 nonwoven fabric, 80 residual chlorine concentration sensor, 90 pH meter, 101 water supply pump, 102 water supply valve, 111 drainage pump, 112 drainage valve.

Claims (7)

A water treatment device that generates residual chlorine,
An electrolytic cell for storing water to be treated;
A pair of electrodes housed in the electrolytic cell;
Power supply means for supplying power to the electrode pair;
A water treatment apparatus comprising a trap provided outside the electrolytic cell and allowing condensation of vapor generated in the electrolytic cell.   The water treatment apparatus according to claim 1, further comprising a forwarding unit for returning the solution condensed in the trap to the electrolytic cell. Residual chlorine concentration detection means for detecting the residual chlorine concentration of the solution in the trap;
Storage means for storing a residual chlorine concentration threshold for the solution in the trap;
Supply means for supplying an alkaline substance into the electrolytic cell;
The apparatus further comprises control means for controlling the supply means so that the alkaline substance is supplied to the electrolytic cell when the residual chlorine concentration detected by the residual chlorine concentration detection means exceeds the threshold value. Or the water treatment apparatus of Claim 2. Further comprising pH detection means for detecting the pH value of the water to be treated contained in the electrolytic cell;
The water treatment apparatus according to claim 3, wherein the control unit causes the supply unit to supply the alkaline substance when a pH value detected by the pH detection unit falls below a predetermined value.   The water treatment apparatus according to any one of claims 1 to 4, wherein the trap includes a nonwoven fabric. The trap further includes an inlet through which steam generated in the electrolytic cell is introduced,
The water treatment apparatus according to claim 5, wherein the nonwoven fabric is installed above the inlet in the trap.   The water treatment apparatus in any one of Claims 1-6 further provided with the fan which sends the vapor | steam in the said electrolytic vessel to the said trap.

Images