Composition ratio identification method and electrolysis condition adjustment method using the same

Abstract

To provide a technology to identify a composition ratio for a hypochlorous acid gas and a chlorine gas contained in discharged air.SOLUTION: A composition ratio identification method includes: a first step of circulating air (target air) containing a hypochlorous acid gas and a chlorine gas in an aqueous sodium hydroxide to prepare a first aqueous solution containing a hypochlorous acid ion and a chloride ion; a second step of identifying a concentration of the hypochlorous acid ion contained in the first aqueous solution with a chlorine concentration meter; a third step of reducing the hypochlorous acid ion contained in the first aqueous solution with a sodium thiosulfate aqueous solution to obtain a chloride ion to prepare a second aqueous solution containing the chloride ion; a fourth step of identifying a concentration of the chloride ion contained in the second aqueous solution with an ion-chromatographic analyzer; and a fifth step of identifying a composition ratio of the hypochlorous acid gas and the chlorine gas contained in the air circulated in the aqueous sodium hydroxide on the basis of information relating to the identified concentration of the hypochlorous acid ion and the identified concentration of the chloride ion.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a composition ratio specifying method and a method for adjusting electrolysis conditions using the same. [Background technology]

[0002] Conventionally, in this type of hypochlorous acid water supply device, an air conditioning system is known that supplies hypochlorous acid in conjunction with a purification system, and sterilizes the space by contacting the air supplied indoors with a gas-liquid contact member that contains a purification component (active oxygen species such as hypochlorous acid) and releasing it (see, for example, Patent Document 1). In addition, in conventional hypochlorous acid water supply devices, an electrolyte such as sodium chloride is added to tap water in an electrolytic cell to perform electrolysis, thereby generating hypochlorous acid water. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-133521 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional hypochlorous acid water supplying device, when the sodium chloride aqueous solution is electrolyzed in a state where the pH of the sodium chloride aqueous solution is biased to the acidic side, or when a high concentration sodium chloride aqueous solution is electrolyzed even when the pH of the sodium chloride aqueous solution is biased to the alkaline side, the air supplied to the room will contain not only hypochlorous acid gas but also chlorine gas, and there is a concern that the generation efficiency of hypochlorous acid gas will decrease during the purification operation of the air conditioning system.For this reason, in recent years, there has been a demand for accurately determining the composition ratio (proportion) of hypochlorous acid gas and chlorine gas contained in the air discharged from the air conditioning system so that the setting conditions of electrolysis in the hypochlorous acid water supplying device can be efficiently adjusted.

[0005] Therefore, the present invention is intended to solve the above-mentioned conventional problems, and aims to provide a technology for identifying the composition ratio of hypochlorous acid gas and chlorine gas contained in the air released from an air conditioning system, and a technology for adjusting electrolysis conditions using the same. [Means for solving the problem]

[0006] In order to achieve this object, the composition ratio determining method according to the present invention includes a first step of passing air containing hypochlorous acid gas and chlorine gas through an alkaline aqueous solution capable of dissolving hypochlorous acid gas and chlorine gas to convert the alkaline aqueous solution into a first aqueous solution containing hypochlorite ions and chloride ions; a second step of determining the concentration of hypochlorite ions contained in the first aqueous solution by a first analysis means; a third step of reducing the hypochlorite ions contained in the first aqueous solution to chloride ions by an aqueous solution containing a reducing agent to convert the first aqueous solution into a second aqueous solution containing chloride ions; a fourth step of determining the concentration of chloride ions contained in the second aqueous solution by a second analysis means; and a fifth step of determining the composition ratio of hypochlorous acid gas and chlorine gas contained in the air passed through the alkaline aqueous solution based on information on the concentration of hypochlorite ions determined in the second step and the concentration of chloride ions determined in the fourth step.

[0007] The method for adjusting electrolysis conditions according to the present invention includes a storage section for storing an aqueous sodium chloride solution or an aqueous potassium chloride solution inside a housing, an electrolysis section provided in the storage section for electrolyzing the aqueous sodium chloride solution or the aqueous potassium chloride solution to generate an aqueous hypochlorous acid solution, an air introduction section for drawing in air from outside the housing and introducing it into the storage section, and an electrolysis section for electrolyzing the aqueous sodium chloride solution or the aqueous potassium chloride solution to generate an aqueous hypochlorous acid solution inside the storage section. A method for adjusting electrolysis conditions in a space purification device including an air discharge unit that discharges air in the space above a solution to the outside of a housing, the method comprising: a discharge step of discharging air from the air discharge unit as air containing hypochlorous acid gas and chlorine gas; an acquisition step of acquiring information regarding the composition ratio of hypochlorous acid gas and chlorine gas identified by the above-mentioned composition ratio identification method; and an adjustment step of adjusting the setting conditions of electrolysis in the electrolysis unit based on the information regarding the composition ratio when the chlorine gas contained in the air discharged from the air discharge unit exceeds a reference value, so that the proportion of chlorine gas contained in the air discharged from the air discharge unit is reduced. Effect of the Invention

[0008] According to the present invention, it is possible to identify the composition ratio of hypochlorous acid gas and chlorine gas contained in the air released from an air conditioning system, and to use the identified ratio to adjust the electrolysis conditions. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a flow chart showing a composition ratio specifying method according to the first embodiment of the present invention. [Diagram 2] FIG. 2 shows the chemical reaction formulas that occur in each step. [Diagram 3] FIG. 3 is a diagram showing state changes of hypochlorous acid gas and chlorine gas contained in the target air. [Figure 4] FIG. 4 is a side cross-sectional view showing the configuration of a space purification device according to a first example that emits target air. [Diagram 5] FIG. 5 is a top view showing the spatial purification device of FIG. [Figure 6] FIG. 6 is a flow chart showing a method for adjusting electrolysis conditions using the composition ratio specifying method. [Figure 7] FIG. 7 is a schematic diagram showing the configuration of a space purification device according to a second example that emits target air. [Figure 8] FIG. 8 is a see-through perspective view showing the configuration of a space purification device mounted on the space purification equipment of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment is an example of the present invention, and does not limit the technical scope of the present invention. Also, each figure described in the embodiment is a schematic diagram, and the size and thickness ratios of each component in each figure do not necessarily reflect the actual dimensional ratios.

[0011] (Embodiment 1) A composition ratio specifying method according to the first embodiment of the present invention will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a flow chart showing the composition ratio specifying method according to the first embodiment of the present invention. Fig. 2 is a diagram showing chemical reaction formulas occurring in each step.

[0012] The composition ratio specifying method according to the first embodiment is a method for specifying a composition ratio of hypochlorous acid gas (HClO gas) and chlorine gas (Cl2 gas) contained in air discharged from a space purification device 101 according to a first example or a space purification equipment 102 (space purification device 211) according to a second example, which will be described later. Specifically, the composition ratio specifying method includes steps S00 to S05 (including steps 1 to 5) shown in FIG.

[0013] The first step is to prepare an aqueous solution of sodium hydroxide of a predetermined concentration by storing it in a container such as an impinger as an alkaline aqueous solution capable of dissolving hypochlorous acid gas and chlorine gas contained in the air circulating through the liquid (step S00). The predetermined concentration of the aqueous solution of sodium hydroxide is determined by the amount of hydrochloric acid produced when the hypochlorous acid produced in step S01 described later is decomposed. Since the reaction is formed (see reaction formula (d) in FIG. 2), the pH of the aqueous sodium hydroxide solution after absorbing the mixed gas may be adjusted to a range of 10 to 12, more preferably to about pH 11, taking into consideration the flow rate of the mixed gas to be absorbed. By doing so, the decrease in the available chlorine concentration in the aqueous sodium hydroxide solution after absorption 24 hours can be suppressed to about 1% or less.

[0014] Here, available chlorine refers to chlorine with oxidizing power, and in an aqueous solution it is dissolved in chlorine gas (Cl2). 、 Dissolved hypochlorous acid gas (HClO), hypochlorous acid ion (ClO - ) The chlorine gas and hypochlorous acid gas dissolved in the aqueous solution are in equilibrium as shown in reaction formulas (e) and (f) in Figure 2. The acid dissociation constant of hypochlorous acid is pKa = 7.5, and in an alkaline aqueous solution with a pH of 10 or higher, 99% or more of the available chlorine exists as hypochlorite ions.

[0015] The material of the container for storing the gas is not particularly limited as long as it does not react with hypochlorous acid gas, chlorine gas, sodium hydroxide, or their reaction products.

[0016] The first step is a step of passing air containing hypochlorous acid gas and chlorine gas from the outside by bubbling or the like through the aqueous sodium hydroxide solution stored in a container to convert the aqueous sodium hydroxide solution into a first aqueous solution containing hypochlorite ions and chloride ions (step S01). Specifically, as shown in reaction formula (a) in FIG. 2, chlorine gas (Cl2) introduced into the aqueous sodium hydroxide solution reacts with sodium hydroxide (NaOH) to change into water (H2O), sodium chloride (NaCl), and sodium hypochlorite (NaClO). Then, sodium chloride (NaCl) is converted into sodium ions (Na + ) and chloride ions (Cl - ) In addition, sodium hypochlorite (NaClO) separates into sodium ions (Na +) and hypochlorite ion (ClO - In other words, if the reacting chlorine gas is "1", then in the sodium hydroxide solution there will be "1" chloride ion and "1" hypochlorite ion.

[0017] On the other hand, hypochlorous acid gas (HClO) introduced into the sodium hydroxide aqueous solution reacts with sodium hydroxide (NaOH) to change into water (HO) and sodium hypochlorite (NaClO). Then, sodium hypochlorite (NaClO) is converted into sodium ions (Na + ) and hypochlorite ion (ClO - In other words, if the reacting hypochlorous acid gas is "1", then there will be "1" hypochlorite ion in the sodium hydroxide solution.

[0018] Here, the flow rate of the mixed gas absorbed into the aqueous sodium hydroxide solution is preferably adjusted so that the hypochlorite ion concentration of the aqueous sodium hydroxide solution after absorbing the mixed gas does not become too high (for example, 1000 ppm or less) in order to keep the decomposition effect of hypochlorous acid shown in reaction formula (a) of Figure 2 small.

[0019] In the second step, the hypochlorite ion (ClO - The step of determining the concentration of chlorine (step S02) is as follows. The chlorine concentration measuring instrument may be a general measuring instrument such as a chlorine meter using iodometric titration or a residual chlorine meter using a DPD (N,N-diethylparaphenylenediamine) reagent, and therefore a description thereof will be omitted.

[0020] In addition, when the concentration unit of the component measured by the chlorine concentration meter is output in "mg / L", it is preferable to convert it to "mol / L".

[0021] In the third step, a sodium thiosulfate aqueous solution is used as the aqueous solution containing a reducing agent to reduce the hypochlorite ions (ClO -) to chloride ions (Cl - ), and converting the first aqueous solution into a second aqueous solution containing chloride ions (Step S03). Specifically, as shown in reaction formula (c) in FIG. 2, sodium hypochlorite (NaClO) in the first aqueous solution undergoes a reduction reaction with sodium thiosulfate (Na2S2O3) and water (H2O) to change into sodium sulfate (Na2SO4), sulfuric acid (H2SO4), and sodium chloride (NaCl). Then, in the second aqueous solution, sodium chloride (NaCl) converts into sodium ions (Na + ) and chloride ions (Cl - ) In other words, if the sodium hypochlorite that reacts is "4", then the second aqueous solution will contain new chloride ions "4". As a result, the first aqueous solution no longer contains sodium hypochlorite, and becomes the second aqueous solution containing the chloride ions that were originally present in the first aqueous solution and the chloride ions that have been reduced from the sodium hypochlorite.

[0022] Here, the sodium thiosulfate aqueous solution may be adjusted to a predetermined reducing agent concentration based on the information on the concentration of hypochlorite ions identified in the second step. Specifically, as shown in reaction formula (c) in Fig. 2, the reducing agent concentration of the sodium thiosulfate aqueous solution is such that 1 mole of sodium thiosulfate is sufficient for 4 moles of sodium hypochlorite to reduce all of the sodium hypochlorite, but in this embodiment, in order to ensure that the hypochlorite ions contained in the first aqueous solution are reduced to chloride ions, the concentration of the sodium thiosulfate aqueous solution is adjusted to contain an excess of sodium thiosulfate, the molar amount of which is about 4 to 5 times.

[0023] Note that the 4- to 5-fold excess amount is merely a guideline, and can be adjusted taking into consideration the following three points: A) that the chloride ion concentration of the sample liquid falls within the range of approximately 1 mg / L to 100 mg / L, which is a range with high measurement accuracy by the ion chromatograph analyzer in step S04 described below; B) that the sodium thiosulfate is at a concentration that does not cause the peak results of the ion chromatograph analyzer to be overshadowed by peaks of other substances; and C) that sodium thiosulfate capable of chloride ionization is mixed in sufficient amount to accommodate fluctuations in hypochlorite ion concentration.

[0024] The fourth step is a step of determining the concentration of chloride ions contained in the second aqueous solution by an ion chromatograph as the second analysis means (step S04). A general measuring instrument may be used as the ion chromatograph, and therefore a description thereof will be omitted.

[0025] When the concentration unit of a component measured by an ion chromatograph is output in "mg / L", it is preferable to convert it to "mol / L".

[0026] In addition, instead of using an ion chromatograph analyzer, the chloride ion concentration may be determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), or the chloride ion concentration may be determined by an analytical method that combines High-Performance Liquid Chromatography (HPLC) and Mass Spectrometry (MS).

[0027] The fifth step is a step of determining the composition ratio of hypochlorous acid gas and chlorine gas contained in the air passed through the aqueous sodium hydroxide solution based on information regarding the concentration of hypochlorite ions determined in the second step and the concentration of chloride ions determined in the fourth step (step S05).

[0028] The process of identifying the composition ratio in step S05 will be described with reference to Fig. 3. Fig. 3 is a diagram showing state changes of hypochlorous acid gas and chlorine gas contained in the target air.

[0029] As shown in FIG. 3, the chlorine gas (Cl2 gas) contained in the target air is dissolved in the sodium hydroxide aqueous solution in step S01, and the chloride ions (Cl - ) and hypochlorite ion (ClO - In this case, if the amount of chlorine gas is X [mol / L], then the amount of chloride ions is X [mol / L] and the amount of hypochlorite ions is X [mol / L]. Meanwhile, the hypochlorite gas (HClO gas) is dissolved in the sodium hydroxide aqueous solution in step S01, and the hypochlorite ions (ClO - In this case, if hypochlorous acid gas is Y [mol / L], it will become Y [mol / L] hypochlorous acid ions.

[0030] Next, hypochlorite ions (ClO - ) is reduced in step S03 to form chloride ions (Cl - ) In this case, since it is reduced to chloride ions of X [mol / L], the chloride ions resulting from chlorine gas are 2X [mol / L]. On the other hand, the hypochlorite ions (ClO - ) is reduced in step S03 to form chloride ions (Cl - ) During this process, it is reduced to Y [mol / L] chloride ions. As a result, the second aqueous solution contains 2X + Y [mol / L] chloride ions.

[0031] Here, if the concentration of hypochlorite ions determined in the second step is A [mol / L] and the concentration of chloride ions determined in the fourth step is B [mol / L], then "A=X+Y" and "B=2X+Y" are established as shown in formulas (1) and (2) in FIG. 3. As a result, X of chlorine gas is calculated as BA [mol / L], and Y of hypochlorous acid gas is calculated as 2A-B [mol / L]. As a result, the ratio of chlorine gas contained in the air circulated through the sodium hydroxide aqueous solution is specified as (BA) / A, and the ratio of hypochlorous acid gas is specified as (2A-B) / A. In other words, the composition ratio of hypochlorous acid gas and chlorine gas contained in the air circulated through the sodium hydroxide aqueous solution can be specified as hypochlorous acid gas:chlorine gas=2A-B:BA.

[0032] As described above, according to the composition ratio specifying method according to the first embodiment, the following effects can be obtained.

[0033] (1) A first step of passing air (target air) containing hypochlorous acid gas and chlorine gas through an alkaline aqueous solution (sodium hydroxide aqueous solution) capable of dissolving hypochlorous acid gas and chlorine gas to convert the alkaline aqueous solution into a first aqueous solution containing hypochlorite ions and chloride ions; a second step of specifying the concentration of hypochlorite ions contained in the first aqueous solution by a first analysis means (chlorine concentration meter); and a second step of reducing the hypochlorite ions contained in the first aqueous solution to chloride ions by an aqueous solution containing a reducing agent (sodium thiosulfate aqueous solution) to convert the hypochlorite ions into chloride ions, thereby converting the first aqueous solution into a first aqueous solution. a third step of preparing a second aqueous solution containing chloride ions; a fourth step of determining the concentration of chloride ions contained in the second aqueous solution by a second analyzing means (ion chromatographic analyzer); and a fifth step of determining the composition ratio of hypochlorous acid gas and chlorine gas contained in the air passed through the alkaline aqueous solution (hypochlorous acid gas:chlorine gas=2A-B:BA) based on information regarding the concentration of hypochlorite ions (A [mol / L]) determined in the second step and the concentration of chloride ions (B [mol / L]) determined in the fourth step.

[0034] This makes it possible to accurately determine the composition ratio of hypochlorous acid gas and chlorine gas contained in the target air.

[0035] (2) In the composition ratio determination method, the aqueous solution containing the reducing agent (aqueous solution of sodium thiosulfate) is adjusted to a predetermined reducing agent concentration (an excessive concentration of 4 to 5 times the molar concentration) based on the information on the concentration of hypochlorite ions (A [mol / L]) determined in the second step. This ensures that the hypochlorite ions contained in the first aqueous solution are reduced to chloride ions.

[0036] The present invention has been described above based on embodiment 1, but the present invention is in no way limited to the above embodiment 1, and it can be easily inferred that various improvements and modifications are possible within the scope of the present invention without departing from the spirit of the present invention.

[0037] In the composition ratio determination method according to the first embodiment, an additive-free aqueous sodium hydroxide solution is used as the alkaline aqueous solution, but the present invention is not limited to this. For example, the aqueous sodium hydroxide solution may be an aqueous solution that already contains a predetermined concentration of chloride ions before air is passed through it. Specifically, a predetermined concentration (15 mg / L to 25 mg / L) of sodium chloride (NaCl) may be added to the aqueous sodium hydroxide solution. In this way, at the initial stage of dissolving hypochlorous acid gas (when there are few hypochlorous acid ions), chloride ions (Cl - ), the decomposition reaction of hypochlorite ions (reduction in available chlorine) shown in reaction formula (d) in Fig. 2 is suppressed, so that the analysis sample used in step S02 can be prepared in a relatively stable state. In other words, the accuracy of the analysis in step S02 can be improved.

[0038] (Example 1) Next, a spatial purification device 101 according to a first example will be described with reference to Fig. 4 and Fig. 5, and then a method for adjusting electrolysis conditions using a composition ratio determination method will be described. Fig. 4 is a side cross-sectional view showing the configuration of the spatial purification device 101 according to the first example that emits target air. Fig. 5 is a top view showing the spatial purification device 101 of Fig. 4.

[0039] First, the configuration of a spatial purification device 101 according to a first example will be described.

[0040] The space purification device 101 performs electrolysis of an aqueous solution L1 containing chloride ions in an electrolytic cell 110 described below, to generate and volatilize hypochlorous acid. The space purification device 101 removes bacteria, fungi, viruses, odors, and the like contained in the air in the external space of the space purification device 101 by discharging the volatilized hypochlorous acid gas into the external space of a housing (not shown) that constitutes the space purification device 101.

[0041] 4 and 5, the spatial purification device 101 includes an electrolytic bath 110, a first supply bath 120a, a second supply bath 120b, a first anion exchange membrane 130a, a second anion exchange membrane 130b, and a current control unit 140. The electrolytic bath 110, the first supply bath 120a, the second supply bath 120b, the first anion exchange membrane 130a, the second anion exchange membrane 130b, and the current control unit 140 are housed in a housing (not shown).

[0042] The electrolytic bath 110 is a bath for storing an aqueous solution L1 containing chloride ions. The aqueous solution L1 is, for example, a dilute sodium chloride aqueous solution or a dilute potassium chloride aqueous solution having a predetermined chloride ion concentration. The electrolytic bath 110 corresponds to the "storage unit" in the claims.

[0043] The first supply tank 120a is a tank for storing a second aqueous solution L2 containing hydroxide ions. The hydroxide ions contained in the aqueous solution L2 in the first supply tank 120a pass through the first anion exchange membrane 130a and are supplied to the aqueous solution L1 in the electrolysis tank 110.

[0044] The first supply tank 120a is a tank for storing an aqueous solution L2 containing hydroxide ions and supplying the hydroxide ions to the aqueous solution L1. The aqueous solution L2 is, for example, an aqueous solution of sodium hydroxide.

[0045] The second supply tank 120b is a tank for storing an aqueous solution L3 containing chloride ions. The chloride ions contained in the aqueous solution L3 in the second supply tank 120b permeate through the second anion exchange membrane 130b and are supplied to the aqueous solution L1 in the electrolytic tank 110. The chloride ion concentration in the aqueous solution L3 is higher than that in the aqueous solution L1. The aqueous solution L3 is, for example, a high-concentration aqueous hydrochloric acid solution.

[0046] The first anion exchange membrane 130a is a membrane-like member that connects the electrolytic cell 110 and the first supply tank 120a in a manner that allows anions to pass therethrough, based on a voltage applied between the electrolytic cell 110 and the first supply tank 120a. More specifically, when a voltage is applied between the electrolytic cell side anode 111 and the first supply tank side cathode 112 described below, first membrane electrolysis is performed via the first anion exchange membrane 130a. By the first membrane electrolysis using the electrolytic cell side anode 111 and the first supply tank side cathode 112, hydroxide ions contained in the aqueous solution L2 pass through the first anion exchange membrane 130a and are supplied to the aqueous solution L1.

[0047] The second anion exchange membrane 130b is a membrane-like member that connects the electrolytic cell 110 and the second supply cell 120b in a manner that allows anions to pass therethrough, based on a voltage applied between the electrolytic cell 110 and the second supply cell 120b. More specifically, when a voltage is applied between the electrolytic cell side anode 111 and the second supply cell side cathode 121 described below, second membrane electrolysis is performed via the second anion exchange membrane 130b. By the second membrane electrolysis using the electrolytic cell side anode 111 and the second supply cell side cathode 121, chloride ions contained in the aqueous solution L3 permeate through the second anion exchange membrane 130b and are supplied to the aqueous solution L1.

[0048] The current control unit 140 controls the current used in the first diaphragm electrolysis and the second diaphragm electrolysis. More specifically, the current control unit 140 controls the current used in the first diaphragm electrolysis performed through the first anion exchange membrane 130a using the electrolytic cell side anode 111 arranged in the electrolytic cell 110 and the first supply cell side cathode 112 arranged in the first supply cell 120a across the electrolytic cell 110 and the first supply cell side cathode 112 arranged in the first supply cell 120a. The current control unit 140 also controls the current used in the second diaphragm electrolysis performed through the second anion exchange membrane 130b using the electrolytic cell side anode 111 arranged in the electrolytic cell 110 and the second supply cell side cathode 121 arranged in the second supply cell 120b across the electrolytic cell 110 and the second supply cell side anode 111 arranged in the electrolytic cell 110 and the second supply cell side cathode 121 arranged in the second supply cell 120b. The electrolytic cell side anode 111 is used in both the first diaphragm electrolysis and the second diaphragm electrolysis.

[0049] Hereinafter, the details of each of the tanks (the electrolytic tank 110, the first supply tank 120a, and the second supply tank 120b) constituting the spatial purification device 101 will be described in more detail with reference to FIGS.

[0050] (electrolytic cell) The electrolytic cell 110 comprises an electrolytic cell-side anode 111 , wiring 113 , an inlet 115 , a mixing space 116 and an outlet 117 .

[0051] The electrolytic cell side anode 111 is an electrode used for electrolysis of the aqueous solution L1 as a pair with the first supply tank side cathode 112 arranged in the first supply tank 120a. A first anion exchange membrane 130a is arranged between the electrolytic cell side anode 111 and the first supply tank side cathode 112. That is, the electrolysis of the aqueous solution L1 and the aqueous solution L2 performed using the pair of the electrolytic cell side anode 111 and the first supply tank side cathode 112 is a diaphragm electrolysis (first diaphragm electrolysis). The first diaphragm electrolysis of the aqueous solution L1 performed using the pair of the electrolytic cell side anode 111 and the first supply tank side cathode 112 produces hypochlorous acid used for space purification. The electrolytic cell side anode 111 corresponds to the "electrolysis unit" in the claims.

[0052] The inlet 115 is an opening through which air flows in from the external space of the housing that constitutes the space purification device 101. The inlet 115 corresponds to an "air introduction section" in the claims.

[0053] The mixing space 116 is a space formed above the electrolytic cell 110 in a state where the aqueous solution L1 is stored in the electrolytic cell 110. The mixing space 116 is a space for mixing hypochlorous acid generated by the first diaphragm electrolysis of the aqueous solution L1 performed using a pair of the electrolytic cell side anode 111 and the first supply cell side cathode 112 with the air of the external space flowing in from the inlet 115. The hypochlorous acid generated by the first diaphragm electrolysis includes hypochlorous acid gas that has been volatilized and gasified, and hypochlorous acid dissolved in the aqueous solution L1. The hypochlorous acid gas is contained in the air that flows in from the inlet 115 and flows out from the outlet 117 to the external space, which will be described later. The hypochlorous acid dissolved in the aqueous solution L1 flows out from the outlet 117 to the external space, which will be described later, by coming into gas-liquid contact with the air that flows in from the inlet 115.

[0054] The outlet 117 is an opening through which mixed air, which is a mixture of the air flowing in from the inlet 115 and hypochlorous acid generated by the first diaphragm electrolysis of the aqueous solution L1, flows out to the external space of the housing. That is, the outlet 117 is an opening through which the mixed air flows out to the external space of the space purification device 101. The outlet 117 corresponds to the "air discharge section" in claim 1.

[0055] The air containing hypochlorous acid that flows out from the outlet 117 to the space outside the space purification device 101 purifies the space of the external space. That is, the air containing hypochlorous acid removes bacteria, fungi, viruses, odors, and the like contained in the air in the space outside the housing. When identifying the composition ratio, the air flowing out from the outlet 117 of the space purification device 101 according to the first example is regarded as air containing a mixed gas in which hypochlorous acid gas contains chlorine gas, and is caused to flow through the sodium hydroxide aqueous solution in step S01.

[0056] (1st supply tank) The first supply tank 120a includes a first supply tank side cathode 112, a wiring 114, and a first exhaust port 123a.

[0057] The first supply tank side cathode 112 is an electrode used in combination with the electrolytic cell side anode 111 for electrolysis of the aqueous solution L2. As described above, the first anion exchange membrane 130a is disposed between the first supply tank side cathode 112 and the electrolytic cell side anode 111. That is, the electrolysis of the aqueous solution L2 performed using the pair of the first supply tank side cathode 112 and the electrolytic cell side anode 111 is membrane electrolysis (first membrane electrolysis). The first membrane electrolysis of the aqueous solution L2 performed using the pair of the first supply tank side cathode 112 and the electrolytic cell side anode 111 generates hydroxide ions and supplies hydroxide ions from the aqueous solution L2 to the aqueous solution L1. In addition, hydrogen is generated by the first membrane electrolysis of the aqueous solution L2 performed using the pair of the first supply tank side cathode 112 and the electrolytic cell side anode 111.

[0058] The first exhaust port 123a is an opening for discharging hydrogen gas generated by the first diaphragm electrolysis of the aqueous solution L2 to the external space of the housing. The first exhaust port 123a may be, for example, a check valve. When a check valve is used as the first exhaust port 123a, hydrogen gas inside the first supply tank 120a is discharged to the external space, but the inflow of gas such as air from the external space can be suppressed. When the first diaphragm electrolysis of the aqueous solution L2 is repeated, hydrogen gas accumulates inside the first supply tank 120a, and the internal pressure of the first supply tank 120a increases. The pressure opens the check valve, and hydrogen gas is discharged to the external space of the first supply tank 120a.

[0059] (2nd supply tank) The second supply tank 120b includes a second supply tank side cathode 121, a wiring 122, and a second outlet 123b.

[0060] The second supply tank side cathode 121 is paired with the electrolytic tank side anode 111 to electrolyze the aqueous solution L3. The electrodes used are the electrolytic cell side anode 111 and the second supply tank side cathode 121. A second anion exchange membrane 130b is disposed between the electrolytic cell side anode 111 and the second supply tank side cathode 121. That is, the electrolysis of the aqueous solution L3 performed using the pair of the electrolytic cell side anode 111 and the second supply tank side cathode 121 is membrane electrolysis (second membrane electrolysis). That is, the electrolytic cell side anode 111 is used for both the first membrane electrolysis and the second membrane electrolysis. Chloride ions are supplied from the aqueous solution L3 to the aqueous solution L1 by the second membrane electrolysis of the aqueous solution L3 performed using the pair of the electrolytic cell side anode 111 and the second supply tank side cathode 121. Also, hydrogen is generated by the second membrane electrolysis of the aqueous solution L3 performed using the pair of the electrolytic cell side anode 111 and the second supply tank side cathode 121.

[0061] The second outlet 123b is an opening for discharging hydrogen gas generated by the second diaphragm electrolysis of the aqueous solution L3 to the external space of the housing. The second outlet 123b may be the same as the first outlet 123a, and therefore a description thereof will be omitted.

[0062] 4 and 5, the spatial purification device 101 according to the first example includes a first diaphragm electrolysis unit E1 and a second diaphragm electrolysis unit E2. The current control unit 140 controls the first current flowing through the first diaphragm electrolysis unit E1 and the second current flowing through the second diaphragm electrolysis unit E2, thereby controlling the chemical reaction occurring in the first diaphragm electrolysis unit E1 and the chemical reaction occurring in the second diaphragm electrolysis unit E2.

[0063] The first membrane-containing electrolysis unit E1 is provided between the electrolytic cell 110 and the first supply cell 120a. The first membrane-containing electrolysis unit E1 performs first membrane-containing electrolysis via the first anion exchange membrane 130a by passing a first current between the electrolytic cell-side anode 111 and the first supply cell-side cathode 112. More specifically, the first membrane-containing electrolysis unit E1 performs membrane-containing electrolysis of the aqueous solution L1 to produce hypochlorous acid and performs membrane-containing electrolysis of the aqueous solution L2 to produce hydroxide ions and hydrogen by passing a first current between the electrolytic cell-side anode 111 and the first supply cell-side cathode 112.

[0064] The second membrane-containing electrolysis unit E2 is provided across the electrolytic cell 110 and the second supply cell 120b. A second current is passed between the electrolytic cell-side anode 111 and the second supply cell-side cathode 121 to perform membrane-containing electrolysis via the second anion exchange membrane 130b. More specifically, the second membrane-containing electrolysis unit E2 performs membrane-containing electrolysis of the aqueous solution L3 to produce hydrogen by passing a second current between the electrolytic cell-side anode 111 and the second supply cell-side cathode 121.

[0065] The current control unit 140 applies the first current and the second current at a predetermined ratio, thereby maintaining the chloride ion concentration of the aqueous solution L1 at a predetermined concentration.

[0066] According to this configuration, chloride ions consumed by the aqueous solution L1 can be appropriately supplied from the aqueous solution L3, and the spatial purification device 101 can stably generate a desired amount of hypochlorous acid gas. Therefore, the desired amount of hypochlorous acid gas can be stably generated for a long period of time, such as one year, without supplying an aqueous solution containing chloride ions from the outside.

[0067] Next, a method for adjusting electrolysis conditions using the composition ratio specifying method in the spatial purification device 101 according to the first example will be described with reference to Fig. 6. Fig. 6 is a flow chart showing the method for adjusting electrolysis conditions using the composition ratio specifying method.

[0068] The method of adjusting the electrolysis conditions is a method of confirming that the spatial purification device 101 is operating with the purification performance (gas composition ratio) that was initially set. The method of adjusting the electrolysis conditions is performed, for example, at the time of initial installation (trial run) of the spatial purification device 101 or during maintenance. This makes it possible to reliably guarantee the purification performance that was initially set for the spatial purification device 101. Specifically, the method for adjusting the electrolysis conditions includes steps S11 to S13 (a releasing step, an obtaining step, and an adjusting step) shown in FIG.

[0069] The first release step is a step (step S11) in which the space purification device 101 is operated to release air as target air from the outlet 117 of the space purification device 101. At this time, the air flowing out from the outlet 117 is regarded as air containing a mixed gas in which hypochlorous acid gas contains chlorine gas, and is made to flow into the sodium hydroxide aqueous solution prepared in step S00 for a predetermined time. Here, the predetermined time is a time adjusted based on the initially set purification performance (concentration of hypochlorous acid gas) and the amount of mixed gas released so that the concentration of hypochlorous acid when dissolved in the sodium hydroxide aqueous solution does not become too high (for example, 1000 ppm or less).

[0070] The next acquisition step is a step of identifying the composition ratio of hypochlorous acid gas and chlorine gas contained in the target air by the composition ratio identification method in the above-mentioned steps S00 to S05, and acquiring information on the identified composition ratio of hypochlorous acid gas and chlorine gas (step S12). Specifically, the ratio of chlorine gas contained in the air circulated through the sodium hydroxide aqueous solution is identified as (BA) / A, and the ratio of hypochlorous acid gas is identified as (2A-B) / A, and acquiring information on the identified composition ratio (ratio).

[0071] The next adjustment step is a step (step S13) of adjusting the set conditions of electrolysis in the first diaphragm electrolysis unit E1 and the second diaphragm electrolysis unit E2 so that the ratio of chlorine gas contained in the air discharged from the outlet 117 of the space purification device 101 decreases when the ratio of chlorine gas contained in the air discharged from the outlet 117 exceeds a reference value, based on the information on the composition ratio (proportion). Specifically, when the ratio of chlorine gas exceeds the reference value, the pH of the aqueous solution L1 in the electrolysis bath 110 is biased toward the acidic side, or the chloride ions (Cl -Since the concentration of hydroxide ions (OH) from the first supply tank 120a to the electrolytic tank 110 may be higher than the initially set condition, the current control unit 140 adjusts the electrolysis rate in the first membrane electrolysis unit E1 to be increased (=the electrolysis rate in the second membrane electrolysis unit E2 to be decreased) based on a database relating to the rate of chlorine gas and the electrolysis rate in the electrolysis unit. - ) is supplied to the electrolytic cell 110 from the second supply tank 120b. - ) supply will decrease, allowing us to get closer to the conditions initially set.

[0072] On the other hand, if the proportion of chlorine gas is equal to or less than the reference value, that is, if the proportion of chlorine gas is within an allowable range, the purification operation is continued as is without adjusting the electrolysis conditions.

[0073] As described above, according to the method for adjusting the electrolysis conditions using the composition ratio specifying method in the spatial purification device 101 according to the first example, the following effects can be obtained.

[0074] (1a) The method for adjusting electrolysis conditions is a method for adjusting electrolysis conditions in a space purification device 101 comprising an electrolytic cell 110 that stores an aqueous solution L1 inside a housing, a first diaphragm-equipped electrolysis unit E1 (electrolytic cell-side anode 111) that is provided inside the electrolytic cell 110 and electrolyzes the aqueous solution L1 to produce an aqueous hypochlorous acid solution, an inlet 115 that draws in air from outside the housing and introduces it into the electrolytic cell 110, and an outlet 117 that releases air in the space above the aqueous hypochlorous acid solution in the electrolytic cell 110 (mixing space 116) to the outside of the housing. The method for adjusting the electrolysis conditions includes a discharging step (step S11) of discharging air from the outlet 117 as air containing hypochlorous acid gas and chlorine gas, an acquiring step (step S12) of acquiring information on the composition ratio of hypochlorous acid gas and chlorine gas identified by the above-mentioned method for identifying the composition ratio, and, when the ratio of chlorine gas contained in the air discharged from the outlet 117 exceeds a reference value, adjusting the setting conditions for electrolysis in the first diaphragm electrolysis unit E1 (electrolytic cell side anode 111) based on the information on the composition ratio so that the ratio of chlorine gas contained in the air discharged from the outlet 117 is reduced. In this case, the releasing step (step S11), the acquiring step (step S12), and the adjusting step (step S13) are performed at the time of initial installation or maintenance of the space purification device 101. This makes it possible to reliably guarantee the purification performance of the space purification device 101 that was initially set.

[0075] The present invention has been described above based on the method for adjusting the electrolysis conditions in the spatial purification device 101 according to the first example, but the present invention is in no way limited thereto, and it can be easily inferred that various improvements and modifications are possible within the scope of the present invention without departing from the spirit thereof.

[0076] In the method for adjusting the electrolysis conditions in the space purification device 101 according to the first example, the setting conditions of the electrolysis are adjusted in accordance with the proportion of chlorine gas in the adjustment step (step S13), but the present invention is not limited to this. For example, the setting conditions of the electrolysis may be adjusted based on the concentration BA [mol / L] of chlorine gas that can be acquired in the acquisition step (step S12). Specifically, when the concentration (content) of the chlorine gas itself contained in the air discharged from the outlet 117 exceeds a concentration reference value, the setting conditions of the electrolysis in the first diaphragm electrolysis unit E1 (electrolysis cell side anode 111) may be adjusted based on information on the concentration so that the concentration (content) of the chlorine gas contained in the air discharged from the outlet 117 is reduced.

[0077] (Example 2) Next, a space purification device 202 (space purification apparatus 211) according to a second example will be described with reference to Fig. 7 and Fig. 8, and then a method for adjusting electrolysis conditions using a composition ratio identification method will be described. Fig. 7 is a schematic diagram showing the configuration of a space purification device 202 according to a second example that emits target air. Fig. 8 is a see-through perspective view showing the configuration of a space purification device 211 mounted on the space purification device 202 of Fig. 7.

[0078] First, the configuration of the spatial purification device 202 (spatial purification device 211) according to the second example will be described.

[0079] The space purification device 202 includes therein a space purification apparatus 211. In more detail, as shown in FIG. 7, the space purification device 202 includes an inlet 208, a dust collection filter 209, a blower 210, the space purification device 211, and an outlet 212.

[0080] The space purification device 202 sucks in suction air 203 from an inlet 208, removes dust from the air, and blows out air 204 containing hypochlorous acid gas from an outlet 212 to the outside (e.g., indoors). When the space purification device 202 blows out the blown air 204 from the outlet 212, the space purification device 202 causes the blown air 204 to contain hypochlorous acid gas by the space purification device 211.

[0081] Inlet port 208 is provided on the lower right side of the front of space purification device 202, and takes in intake air 203 from inside the room into space purification device 202.

[0082] Dust collection filter 209 is a member that purifies air passing through it. Dust collection filter 209 is provided so that suction air 203 sucked in from suction port 208 passes through it. Suction air 203 that passes through dust collection filter 209 is cleaned by removing fine particles by dust collection filter 209. For example, a HEPA filter is used as dust collection filter 209.

[0083] The blower 210 is a member that draws in the suction air 203 from the suction port 208 and generates pressure for blowing it out from the outlet 212 into the room as blown air 204. The blower 210 is installed downstream of the dust-collecting filter 209 in an internal air passage that communicates between the suction port 208 and the outlet 212. The suction air 203 that passes through the dust-collecting filter 209 and is sucked into the blower 210 by the operation of the blower 210 becomes dust-free air 205 through the blower 210. Then, Then, in the process of flowing through the internal air passage, the dust-free air 205 is mixed with discharged air 207 (air containing hypochlorous acid gas) discharged from the space purification device 211, and is blown out as blown air 204. The blower 210 is configured to have a motor section, a fan section rotated by the motor section, and a scroll-shaped casing section surrounding them, but since a general blower fan may be used, detailed description will be omitted.

[0084] The space purification device 211 takes in a part of the dust-removed air 205 as the introduced air 206, and after containing hypochlorous acid gas in the introduced air 206 inside the space purification device 211 (the upper space 223 in the storage section 213 described later), merges the introduced air 206 with the dust-removed air 205 as the discharged air 207. As a result, the dust-removed air 205 becomes air containing hypochlorous acid gas. Note that the wind pressure of the blower 210 can be used as the driving force for sucking in the introduced air 206 and discharging it as the discharged air 207. For example, if an inlet for the introduced air 206 is provided so as to face the flow direction of the dust-removed air 205 created by the blower 210 and an outlet for the discharged air 207 is provided in a direction perpendicular to the flow direction of the dust-removed air 205 created by the blower 210, the introduced air 206 can be introduced into the space purification device 211 by the wind pressure of the blower 210, and the discharged air 207 can be discharged from the space purification device 211. The spatial purification device 211 will be described in detail later.

[0085] The air outlet 212 is provided on the top surface of the space purification device 202, and blows out the dust-free air 205 containing the hypochlorous acid gas after flowing through the internal air passage into the room as blown air 204.

[0086] With the above configuration, the space purification device 202 can suck in indoor air as suction air 203, remove dust therefrom, and blow out the air into the room as blown air 204 containing hypochlorous acid gas.

[0087] Next, the configuration of the space purification device 211 incorporated in the space purification equipment 202 will be described with reference to FIG.

[0088] The space purification device 211 is a unit that is detachably installed inside the space purification device 202. The space purification device 211 takes in the dust-removed air 205 of the space purification device 202 from the air introduction part 215 as introduced air 206, and releases it from the air release part 216 to the internal air passage of the space purification device 202 as released air 207 containing hypochlorous acid gas.

[0089] More specifically, as shown in FIG. 8, the spatial purification device 211 is configured to include an air inlet section 215, an air discharge section 216, a storage section 213, an electrolysis section 214, an agitation section 220, and a sediment filter 219.

[0090] The air introduction section 215 is a tubular member that connects the internal air passage of the space purification device 202 and the sealed upper space 223 above the storage section 213, and takes in the introduced air 206 into the space purification device 211. Specifically, the air introduction section 215 has an inlet located on the internal air passage side and an outlet located on the upper space 223 side. The inlet on the internal air passage side of the air introduction section 215 is a tube opening for taking in the dust-removed air 205 as the introduced air 206, and is installed so that the direction of the inlet faces the flow direction of the dust-removed air 205 created by the blower 210 (see FIG. 7). The outlet on the upper space 223 side of the air introduction section 215 is a tube opening for introducing the introduced air 206 into the upper space 223, and is installed on the upper surface of the space purification device 211. As a result, in the air introduction section 215, the introduction air 206 taken in from the introduction port is supplied to the upper space 223 from the outlet port.

[0091] The air discharge part 216 is a tubular member that connects the sealed upper space 223 at the top of the storage part 213 and the internal air passage of the space purification device 202, and discharges the air from the inside of the space purification device 211. The air discharge section 216 discharges the discharged air 207. Specifically, the air discharge section 216 has an inlet located on the upper space 223 side and an outlet located on the internal air passage side. The inlet on the upper space 223 side of the air discharge section 216 is installed on the upper surface of the space purification device 211. The outlet on the internal air passage side of the air discharge section 216 is a pipe opening for discharging the discharged air 207 containing hypochlorous acid gas, and is installed so that the direction of the outlet is perpendicular to the flow direction of the dust-removed air 205 created by the blower 210 (see FIG. 7). In other words, the air discharge section 216 blows the introduced air 206 taken into the inside of the space purification device 211 from the air introduction section 215 into the internal air passage of the space purification device 202 as the discharged air 207 containing hypochlorous acid gas. The outlet of the air discharge section 216 is installed downstream of the internal air passage from the inlet of the air introduction section 215. The process in which the introduced air 206 contains hypochlorous acid gas will be described later.

[0092] The storage unit 213 is a member that forms a sealed internal space with the air introduction unit 215 and the air release unit 216 attached, and stores the electrolytic solution 213a and the hypochlorous acid aqueous solution 213b therein. The storage unit 213 also has an upper space 223 above the liquid levels of the electrolytic solution 213a and the hypochlorous acid aqueous solution 213b.

[0093] Here, the storage section 213 stores a mixed solution of the electrolytic solution 213a and the aqueous hypochlorous acid solution 213b. In the following, the two will be distinguished and will be referred to as the electrolytic solution 213a when the aqueous hypochlorous acid solution is generated by electrolysis, and as the aqueous hypochlorous acid solution 213b when the purification operation is performed to release hypochlorous acid gas.

[0094] The electrolyte 213a is an aqueous solution for generating the hypochlorous acid aqueous solution 213b by electrolysis, and is an aqueous solution in which sodium chloride or potassium chloride is dissolved. In the space purification device 211 mounted on the space purification equipment 202 according to the second example, the electrolyte 213a is stored in the storage section 213 in a state in which the electrolyte 213c made of sodium chloride or potassium chloride is not completely dissolved and the electrolyte 213c is precipitated.

[0095] The precipitated electrolyte 213c is a precipitate of sodium chloride or potassium chloride, and serves to resupply the chloride ions consumed from the electrolyte 213a by electrolysis to the electrolyte 213a.

[0096] In the space purification device 211 mounted on the space purification equipment 202 according to the second example, sodium chloride or potassium chloride is used as the electrolyte 213c, but the electrolyte 213c is not limited to sodium chloride or potassium chloride. As will be described later, since the presence of chloride ions is sufficient to generate the hypochlorous acid aqueous solution 213b, it is also possible to use other chlorides such as calcium chloride or lithium chloride.

[0097] The hypochlorous acid aqueous solution 213b is a solution produced by electrolyzing the electrolytic solution 213a in a state in which the electrolyte 213c is precipitated in the electrolytic solution 213a, and is a so-called aqueous solution containing hypochlorous acid. The hydrogen ion concentration (pH) of the hypochlorous acid aqueous solution 213b is preferably 5 to 13, and more preferably 5 to 7. This is because there is a risk that the hypochlorous acid aqueous solution 213b will evaporate as chlorine gas if the pH is below 5, and also because, if the pH is 5 or higher, the lower the pH, the more likely it is to evaporate as hypochlorous acid gas.

[0098] As described above, the storage section 213 stores the electrolytic solution 213a in a state in which the electrolyte 213c is precipitated in the electrolytic solution 213a, and has an upper space 223 above the liquid surface of the electrolytic solution 213a. The storage section 213 is partitioned into a solute region 217 in which the electrolyte 213c is precipitated, and a solution region 218 in which an electrolysis section 214 and an agitation section 220, which will be described later, are provided.

[0099] The solute region 217 is located at the bottom side of the reservoir 213 and contains the precipitate of electrolyte 213c. This is a region for holding an electrolyte 213a containing the electrolyte.

[0100] The solution region 218 is located above the solute region 217, and is a region that holds the electrolytic solution 213a that does not contain precipitates of the electrolyte 213c. The electrolysis unit 214 and the stirring unit 220 are installed in a state of being immersed in the solution region 218. In addition, a precipitate filter 219 is provided between the solute region 217 and the solution region 218. Specifically, the precipitate filter 219 is provided on the bottom side (solute region 217 side) of the solution region 218 so as to block an opening that communicates between the solute region 217 and the solution region 218, which are partitioned from each other. The precipitate filter 219 will be described later.

[0101] The electrolyte solution 213a in the solute region 217 and the solution region 218 may be read as the aqueous hypochlorous acid solution 213b, or as a mixture of the electrolyte solution 213a and the aqueous hypochlorous acid solution 213b.

[0102] The upper space 223 is an air region generated above the liquid levels of the electrolytic solution 213a and the hypochlorous acid aqueous solution 213b inside the storage section 213. The upper space 223 is connected in communication with the internal air passage of the space purification device 202 by the air introduction section 215 and the air discharge section 216. Then, when the blower 210 is in operation, the introduced air 206 is introduced into the upper space 223 from the internal air passage of the space purification device 202 through the air introduction section 215. Then, by introducing the introduced air 206 into the upper space 223, the air in the upper space 223 (air containing hypochlorous acid gas) is pushed out as the discharged air 207 from the air discharge section 216 into the internal air passage.

[0103] The electrolysis unit 214 is a member that electrolyzes the electrolytic solution 213a stored in the storage unit 213 to generate the hypochlorous acid aqueous solution 213b. The electrolysis unit 214 is installed on the bottom side of the solution region 218, immersed in the electrolytic solution 213a in the solution region 218. The electrolysis unit 214 is, for example, a pair of electrodes, an anode and a cathode, configured by having a catalyst film on the surface of a conductive substrate. The electrolysis unit 214 electrolyzes the electrolytic solution 213a by passing current through the pair of electrodes. As a result, the chloride ions contained in the electrolytic solution 213a are electrolyzed in the electrolysis unit 214, and hypochlorous acid is generated. At this time, the higher the concentration of the chloride ions, the higher the hypochlorous acid generation efficiency. Therefore, in order to generate hypochlorous acid while maintaining the hypochlorous acid generation efficiency, it is important to maintain the concentration of the chloride ions constant. In the space purification device 211 mounted on the space purification device 202 according to the second example, the precipitated electrolyte 213c supplies the chloride ions consumed from the electrolyte solution 213a to the electrolyte solution 213a. Specifically, it has a role of always keeping the chloride ions in the electrolyte solution 213a in a saturated state (about 4.4 mol / L in the case of sodium chloride, about 3.4 mol / L in the case of potassium chloride). As a result, even if the amount of the electrolyte solution 213a that can be stored in the storage unit 213 by miniaturizing it is small, the concentration of the chloride ions contained in the electrolyte solution 213a can be kept constant, and the hypochlorous acid generation efficiency can be maintained.

[0104] The stirring unit 220 is a member that stirs the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b stored in the storage unit 213 within the storage unit 213. The stirring unit 220 is installed with its main part immersed in the electrolyte solution 213a in the solution region 218, vertically above the electrolysis unit 214. The stirring unit 220 has an aqueous solution suction port 220a, an aqueous solution outlet 220b, and a drive unit 220c, and by operating the drive unit 220c, the stirring unit 220 sucks in the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b from the aqueous solution suction port 220a and blows out the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b from the aqueous solution outlet 220b.

[0105] Aqueous solution suction port 220a is a cylindrical suction port that draws in electrolyte 213a and hypochlorous acid aqueous solution 213b from storage portion 213. Aqueous solution suction port 220a is installed in a substantially horizontal state with respect to the bottom of storage portion 213 and facing the side surface of storage portion 213.

[0106] The aqueous solution outlet 220b is an outlet that discharges the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b sucked in from the aqueous solution suction port 220a into the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b in the storage section 213. The aqueous solution outlet 220b is installed facing the liquid levels of the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b vertically upward. The aqueous solution outlet 220b blows out the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b toward the upper space 223 between the air introduction section 215 and the air discharge section 216 to generate a water flow (not shown).

[0107] The driving unit 220c is a motor member that generates a water flow for stirring the solution. More specifically, the driving unit 220c is driven to rotate, thereby generating a flow that sucks the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b from the aqueous solution suction port 220a and blows out the electrolyte solution 213a and the hypochlorous acid aqueous solution 213b from the aqueous solution outlet 220b. The driving unit 220c is installed outside the storage unit 213, unlike the main part (the aqueous solution suction port 220a and the aqueous solution outlet 220b).

[0108] The stirring unit 220 has a role of accelerating the electrolysis of the electrolytic solution 213a and the generation of hypochlorous acid gas. As a function of increasing the amount of hypochlorous acid produced by electrolysis, the operation of the stirring unit 220 generates a stirred water flow, which will be described later, and this can suppress adhesion of bubbles generated in the electrolysis unit 214 to the electrolysis unit 214. In addition, as a function of increasing the supply amount of hypochlorous acid gas, the amount of hypochlorous acid gas contained in the introduced air 206 introduced from the air introduction unit 215 can be increased by blowing the hypochlorous acid aqueous solution 213b toward the upper space 223.

[0109] The precipitate filter 219 is a filter for preventing the electrolyte 213c precipitated in the solute region 217 from floating due to the water flow generated by the agitator 220 and reaching the electrolysis section 214. The precipitate filter 219 is provided between the solute region 217 and the solution region 218. In this way, the precipitate filter 219 prevents the precipitate of the electrolyte 213c from floating up and flowing from the solute region 217, where the electrolyte 213c precipitates, into the solution region 218, where the electrolysis section 214 is installed.

[0110] With the above configuration, the space purification device 211 mounted on the space purification device 202 of the second example can take in dust-free air 205 from the internal air duct of the space purification device 202 as introduced air 206, and release it to the internal air duct as discharged air 207 containing hypochlorous acid gas.

[0111] The method of adjusting the electrolysis conditions using the composition ratio determination method in the space purification device 211 mounted on the space purification equipment 202 of the second example is carried out by including each process (release process, acquisition process, and adjustment process) of steps S11 to S13 shown in FIG. 6, similar to the space purification device 101 of the first example.

[0112] Specifically, in the release step, the space purification device 202 is operated to release air (released air 207) from the air release section 216 of the space purification device 211 as the target air. At this time, the released air 207 is regarded as air containing a mixed gas in which hypochlorous acid gas contains chlorine gas, and is made to flow into the sodium hydroxide aqueous solution prepared in step S00 for a predetermined time. Here, the predetermined time is a time adjusted based on the initially set purification performance (concentration of hypochlorous acid gas) and the amount of mixed gas released so that the concentration of hypochlorous acid when dissolved in the sodium hydroxide aqueous solution does not become too high (for example, 1000 ppm or less).

[0113] In the acquisition process, the composition ratio of hypochlorous acid gas and chlorine gas contained in the target air is identified by the composition ratio identification method in steps S00 to S05 described above. Information regarding the composition ratio of the hypochlorous acid gas and chlorine gas that have been determined is obtained. Specifically, the ratio of chlorine gas contained in the air circulated through the sodium hydroxide aqueous solution is determined to be (BA) / A, and the ratio of hypochlorous acid gas is determined to be (2A-B) / A, and information regarding the determined composition ratio (ratio) is obtained.

[0114] In the adjustment process, based on information regarding the identified composition ratio (proportion), when the proportion of chlorine gas contained in the discharged air 207 exceeds a reference value, the set conditions of electrolysis in the electrolysis unit 214 are adjusted so that the proportion of chlorine gas contained in the discharged air 207 is reduced.

[0115] On the other hand, if the proportion of chlorine gas is equal to or less than the reference value, that is, if the proportion of chlorine gas is within an allowable range, the purification operation is continued as is without adjusting the electrolysis conditions.

[0116] As described above, according to the method for adjusting the electrolysis conditions using the composition ratio specifying method in the space purification device 211 mounted on the space purification equipment 202 according to the second example, the following effects can be obtained.

[0117] (1b) The method for adjusting the electrolysis conditions is a method for adjusting the electrolysis conditions in a space purification device 211 including a storage section 213 that stores a sodium chloride aqueous solution or a potassium chloride aqueous solution (electrolyte 213a) inside a housing, an electrolysis section 214 that is provided in the storage section 213 and electrolyzes the electrolyte 213a to produce a hypochlorous acid aqueous solution 213b, an air introduction section 215 that draws in air from outside the housing and introduces it into the storage section, and an air discharge section 216 that discharges air in the space 223 above the hypochlorous acid aqueous solution 213b in the storage section 213 to the outside of the housing. The method for adjusting the electrolysis conditions includes a release step (step S11) of releasing air (released air 207) from the air release section 216 as air containing hypochlorous acid gas and chlorine gas, an acquisition step (step S12) of acquiring information on the composition ratio of hypochlorous acid gas and chlorine gas identified by the above-mentioned composition ratio identification method, and an adjustment step (step S13) of adjusting the set conditions of electrolysis in the electrolysis section 214 based on the information on the composition ratio when the ratio of chlorine gas contained in the air (released air 207) released from the air release section 216 exceeds a reference value so that the ratio of chlorine gas contained in the air (released air 207) released from the air release section 216 is reduced. At this time, the release step (step S11), the acquisition step (step S12), and the adjustment step (step S13) are performed at the time of initial installation or maintenance of the space purification device 202 (space purification device 211). This makes it possible to reliably guarantee the initially set purification performance of the space purification device 202 (space purification device 211).

[0118] (2b) In the spatial purification device 211, the electrolysis unit 214 is configured to electrolyze the electrolyte 213a in a state in which sodium chloride or potassium chloride (hereinafter, electrolyte 213c) is precipitated in the electrolyte 213a, thereby generating an aqueous hypochlorous acid solution 213b.

[0119] According to this configuration, even if the electrolyte 213c contained in the electrolytic solution 213a is consumed by the electrolysis of the electrolytic solution 213a, the precipitated electrolyte 213c is dissolved in the electrolytic solution 213a and replenished, so that it is possible to suppress a decrease in the concentration of the electrolyte 213c in the electrolytic solution 213a during electrolysis of the electrolytic solution 213a. This makes it possible to suppress a decrease in the efficiency of hypochlorous acid production (the ratio of the generated hypochlorous acid to the current value passed through the electrolytic solution 213a) that accompanies a decrease in the concentration of the electrolyte 213c, so that it is possible to stabilize the amount of hypochlorous acid produced by the electrolysis of the electrolytic solution 213a. In other words, even if the amount of the electrolyte 213a that can be stored in the storage unit 213 by miniaturizing the space purification device 211 is small, it is possible to provide the space purification device 211 that can stably maintain the amount of hypochlorous acid gas contained in the released air.

[0120] The present invention has been described above based on the method for adjusting the electrolysis conditions in the space purification device 202 (space purification apparatus 211) according to the second example, but the present invention is in no way limited thereto, and it can be easily imagined that various improvements and modifications are possible within the scope that does not deviate from the spirit of the present invention. [Industrial Applicability]

[0121] The composition ratio determination method and the method for adjusting electrolysis conditions using the same according to the present invention are useful as a technology for determining the composition ratio of hypochlorous acid gas and chlorine gas contained in the air released from a small air conditioning system, and as a technology for adjusting electrolysis conditions using the same. [Explanation of symbols]

[0122] 101 Space Purification Device 110 Electrolytic cell 111 Electrolytic cell side anode 112 1st supply tank side cathode 113 Wiring 114 Wiring 115 Inlet 116 Mixed space 117 Outlet 120a 1st supply tank 120b 2nd supply tank 121 2nd supply tank side cathode 122 Wiring 123a 1st outlet 123b 2nd outlet 130a First anion exchange membrane 130b Second anion exchange membrane 140 Current control section E1 1st diaphragm electrolytic section E2 Second diaphragm electrolytic section L1 aqueous solution L2 aqueous solution L3 aqueous solution 202 Space Purification Equipment 203 Intake air 204 Blowout air 205 Dust-free air 206 Intake air 207 Exhaust Air 208 Intake port 209 Dust filter 210 Blower 211 Space Purification Device 212 Air outlet 213 Storage Unit 213a Electrolyte 213b Hypochlorous acid solution 213c electrolyte 214 Electrolytic section 215 Air Intake Section 216 Air discharge section 217 Solute region 218 Solution area 219 Sediment Filter 220 Stirring section 220a Aqueous solution inlet 220b Aqueous solution outlet 220c Drive Unit 223 Upper space

Claims

1. A first step of passing air containing hypochlorous acid gas and chlorine gas through an alkaline aqueous solution capable of dissolving hypochlorous acid gas and chlorine gas, and converting the alkaline aqueous solution into a first aqueous solution containing hypochlorous acid ions and chloride ions; A second step of determining the concentration of hypochlorite ions contained in the first aqueous solution by a first analysis means; A third step of reducing the hypochlorite ions contained in the first aqueous solution to chloride ions using an aqueous solution containing a reducing agent, and converting the first aqueous solution into a second aqueous solution containing chloride ions; a fourth step of determining the concentration of chloride ions contained in the second aqueous solution by a second analysis means; A fifth step of determining a composition ratio of the hypochlorous acid gas and the chlorine gas contained in the air circulated through the alkaline aqueous solution based on information regarding the concentration of hypochlorous acid ions determined in the second step and the concentration of chloride ions determined in the fourth step; A composition ratio determination method comprising:

2. The first analysis means is a chlorine concentration meter, The second analysis means is an ion chromatograph. The composition ratio determining method according to claim 1 .

3. The aqueous solution containing the reducing agent is adjusted to have a predetermined reducing agent concentration based on the information on the concentration of hypochlorite ions specified in the second step. The composition ratio determining method according to claim 1 .

4. The aqueous solution containing a reducing agent is an aqueous solution of sodium thiosulfate. The composition ratio determining method according to claim 3 .

5. The alkaline aqueous solution is an aqueous solution that contains chloride ions at a predetermined concentration before the air is passed through the aqueous solution. The composition ratio determining method according to claim 1 .

6. The alkaline aqueous solution is an aqueous sodium hydroxide solution. The composition ratio determining method according to claim 5 .

7. The air containing hypochlorous acid gas and chlorine gas is air that has been in gas-liquid contact with a hypochlorous acid aqueous solution produced by electrolysis of a saturated aqueous solution of sodium chloride or potassium chloride in which solutes have precipitated. The composition ratio determining method according to claim 1 .

8. a storage section for storing an aqueous sodium chloride solution or an aqueous potassium chloride solution inside the housing; An electrolysis unit provided in the storage unit, which electrolyzes the sodium chloride aqueous solution or the potassium chloride aqueous solution to generate a hypochlorous acid aqueous solution; an air introduction section that draws in air from the outside of the housing and introduces it into the storage section; An air discharge unit that discharges air in a space above the aqueous hypochlorous acid solution in the storage unit to the outside of the housing; A method for adjusting electrolysis conditions in a space purification device comprising: A discharging step of discharging air from the air discharging section as the air containing hypochlorous acid gas and chlorine gas; An acquisition step of acquiring information regarding the composition ratio of hypochlorous acid gas and chlorine gas identified by the composition ratio identification method according to claim 1 or 7; an adjustment step of adjusting the set conditions of electrolysis in the electrolysis unit based on the information on the composition ratio when the ratio of chlorine gas contained in the air discharged from the air discharge unit exceeds a reference value so that the ratio of chlorine gas contained in the air discharged from the air discharge unit is reduced; The method for adjusting electrolysis conditions comprises:

9. The releasing step, the acquiring step, and the adjusting step are performed at the time of initial installation or maintenance of the space purification device. The method for adjusting electrolysis conditions according to claim 8.

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