EP-4736893-A1 - SPACE PURIFICATION DEVICE

EP4736893A1EP 4736893 A1EP4736893 A1EP 4736893A1EP-4736893-A1

Abstract

Space purification device (1) includes: electrolysis tank (10) configured to store first aqueous solution (L1); supply tank (20) configured to store second aqueous solution (L2) and supply chloride ions to first aqueous solution (L1); electrolysis tank-side anode (11) and electrolysis tank-side cathode (12) each provided in electrolysis tank (10); supply tank-side cathode (21) provided in supply tank (20); anion exchange membrane (30) disposed between electrolysis tank (10) and supply tank (20) and capable of permeating anions based on a voltage applied between electrolysis tank-side anode (11) and supply tank-side cathode (21); and current controller (40) configured to control the current to supplement chloride ions contained in first aqueous solution (L1) and decreased in number through the electrolysis, allowing chloride ions contained in second aqueous solution (L2) to permeate through anion exchange membrane (30) and be supplied to first aqueous solution (L1).

Inventors

YAMAGUCHI, SHOTARO
HAYASHI, TOMOHIRO
IIDA, KANAKO
WADA, TAKUYA
SHIMOOKA. Yusuke

Assignees

Panasonic Intellectual Property Management Co., Ltd.

Dates

Publication Date: 20260506
Application Date: 20240603

Claims (13)

A space purification device comprising: an electrolysis tank configured to store a first aqueous solution containing chloride ions; a supply tank configured to store a second aqueous solution containing chloride ions at a higher concentration than the first aqueous solution and supply chloride ions to the first aqueous solution; an electrolysis tank-side anode and an electrolysis tank-side cathode each provided in the electrolysis tank; a supply tank-side cathode provided in the supply tank; an anion exchange membrane disposed between the electrolysis tank and the supply tank and capable of permeating anions based on a voltage applied between the electrolysis tank-side anode and the supply tank-side cathode; a non-barrier membrane electrolysis part provided in the electrolysis tank and subjecting the first aqueous solution to non-barrier membrane electrolysis to generate hypochlorous acid with a first current flowing between the electrolysis tank-side anode and the electrolysis tank-side cathode; a barrier membrane electrolysis part provided over the electrolysis tank and the supply tank and performing barrier membrane electrolysis via the anion exchange membrane with a second current flowing between the electrolysis tank-side anode and the supply tank-side cathode; and a current controller configured to control the second current to supplement chloride ions contained in the first aqueous solution and decreased in number through the non-barrier membrane electrolysis, allowing chloride ions contained in the second aqueous solution to permeate through the anion exchange membrane and be supplied to the first aqueous solution.
The space purification device according to claim 1, wherein the current controller flows the first current and the second current at a predetermined ratio to maintain a chloride ion concentration of the first aqueous solution at a predetermined concentration.
The space purification device according to claim 1, wherein the current controller includes: a voltage acquisition unit configured to acquire a voltage between the electrolysis tank-side anode and the electrolysis tank-side cathode; a calculation unit configured to calculate electric conductivity of the first aqueous solution based on the voltage acquired by the voltage acquisition unit; and an estimation unit configured to estimate a concentration of the first aqueous solution based on the electric conductivity calculated by the calculation unit, and wherein the current controller: simultaneously flows the first current and the second current; changes a current ratio between the first current and the second current to increase an amount of chloride ions permeating through the anion exchange membrane from the second aqueous solution and supplied to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is lower than a predetermined concentration; and changes a current ratio between the first current and the second current to decrease an amount of chloride ions permeating through the anion exchange membrane from the second aqueous solution and supplied to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is higher than the predetermined concentration.
The space purification device according to claim 3, wherein a current ratio between the first current and the second current is not changed when a chloride ion concentration of the first aqueous solution is equal to the predetermined concentration.
The space purification device according to claim 1, wherein the current controller includes: a voltage acquisition unit configured to acquire a voltage between the electrolysis tank-side anode and the electrolysis tank-side cathode; a calculation unit configured to calculate electric conductivity of the first aqueous solution based on the voltage acquired by the voltage acquisition unit; and an estimation unit configured to estimate a concentration of the first aqueous solution based on the electric conductivity calculated by the calculation unit, and wherein the current controller: flows the first current at a predetermined value and simultaneously controls the second current; and when the second current is controlled, flows the second current to increase an amount of chloride ions permeating through the anion exchange membrane from the second aqueous solution and supplied to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is lower than a predetermined concentration; and stops the second current to stop supplying chloride ions from the second aqueous solution to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is higher than the predetermined concentration.
The space purification device according to claim 1, wherein the current controller includes: a voltage acquisition unit configured to acquire a voltage between the electrolysis tank-side anode and the electrolysis tank-side cathode; a calculation unit configured to calculate electric conductivity of the first aqueous solution based on the voltage acquired by the voltage acquisition unit; and an estimation unit configured to estimate a concentration of the first aqueous solution based on the electric conductivity calculated by the calculation unit, and wherein the current controller: stops the first current and simultaneously flows the second current to increase an amount of chloride ions permeating through the anion exchange membrane from the second aqueous solution and supplied to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is lower than a predetermined concentration; and stops the second current and simultaneously flows the first current to stop supplying chloride ions from the second aqueous solution to the first aqueous solution, when a chloride ion concentration of the first aqueous solution is higher than the predetermined concentration.
The space purification device according to claim 1, wherein the electrolysis tank-side anode, the electrolysis tank-side cathode, and the supply tank-side cathode are each an electrolysis tank-side anode plate, an electrolysis tank-side cathode plate, and a supply tank-side cathode plate, each having a plate shape; the electrolysis tank-side anode plate and the electrolysis tank-side cathode plate are inserted to an inside of the electrolysis tank from an outside of the electrolysis tank, and the supply tank-side cathode plate is inserted to an inside of the supply tank from an outside of the supply tank; the electrolysis tank-side anode plate has an electrolysis tank-side anode plate immersion part disposed inside the electrolysis tank, and an electrolysis tank-side anode plate protrusion part disposed outside the electrolysis tank; the electrolysis tank-side cathode plate has an electrolysis tank-side cathode plate immersion part disposed inside the electrolysis tank, and an electrolysis tank-side cathode plate protrusion part disposed outside the electrolysis tank; the supply tank-side cathode plate has a supply tank-side cathode plate immersion part disposed inside the supply tank, and a supply tank-side cathode plate protrusion part disposed outside the supply tank; the electrolysis tank-side anode plate immersion part and the electrolysis tank-side cathode plate immersion part are entirely immersed in the first aqueous solution; and the supply tank-side cathode plate immersion part is entirely immersed in the second aqueous solution.
The space purification device according to claim 1, wherein the electrolysis tank-side anode and the supply tank-side cathode are each an electrolysis tank-side anode tube and a supply tank-side cathode tube each having a cylindrical shape or a polygonal tube shape; the electrolysis tank-side cathode is an electrolysis tank-side cathode tube having a cylindrical shape or a polygonal tube shape, or an electrolysis tank-side cathode rod having a rod shape; the electrolysis tank-side anode tube, and the electrolysis tank-side cathode tube or the electrolysis tank-side cathode rod, are entirely immersed in the first aqueous solution; and the supply tank-side cathode tube is entirely immersed in the second aqueous solution.
The space purification device according to claim 7, comprising: a water level detection unit configured to detect a position of a liquid level of the first aqueous solution; and a water supply unit configured to supply water to the electrolysis tank to keep the position of the liquid level detected by the water level detection unit not lower than upper ends of the electrolysis tank-side anode plate immersion part and the electrolysis tank-side cathode plate immersion part.
The space purification device according to claim 7, wherein the electrolysis tank-side anode plate and the supply tank-side cathode plate are: each close to the anion exchange membrane, and disposed, planes of the plate shapes facing each other via the anion exchange membrane; and the electrolysis tank-side cathode plate is: disposed, a plane of the plate shape facing the plane of the plate shape of the electrolysis tank-side anode plate.
The space purification device according to claim 7, wherein for each of the electrolysis tank-side anode plate, the electrolysis tank-side cathode plate, and the supply tank-side cathode plate, the plate shape is a rectangle; a short direction of the rectangle is disposed along a vertical direction; and a long direction of the rectangle is disposed along a horizontal direction.
The space purification device according to claim 1, wherein the non-barrier membrane electrolysis part includes: the electrolysis tank-side anode, and the electrolysis tank-side cathode; and the barrier membrane electrolysis part includes: the electrolysis tank-side anode, the supply tank-side cathode, and the anion exchange membrane.
The space purification device according to claim 1, comprising: a case housing the electrolysis tank and the supply tank; an inflow port disposed above a liquid level of the first aqueous solution stored in the electrolysis tank inside the case, air from an outside space of the case flowing into the inflow port; a mixing space mixing the volatilized hypochlorous acid and the air having flowed in from the inflow port; and an outflow port flowing out a mixed air mixed in the mixing space to the outside space.

Description

TECHNICAL FIELD The present disclosure relates to a space purification device. BACKGROUND ART PTL 1 discloses an air purification device that removes bacteria, fungi, viruses, odors, and the like contained in the air using hypochlorous acid generated by electrolyzing an aqueous solution containing chloride ions. Citation List Patent Literature PTL 1: Unexamined Japanese Patent Publication No. 2019-174032 SUMMARY OF THE INVENTION When a conventional space purification device is downsized, the tank to store an aqueous solution used for electrolysis is also downsized. When the tank is downsized, the amount of the aqueous solution that can be stored is reduced as compared with the conventional space purification device. Therefore, there is a problem that when electrolysis is repeatedly performed in the downsized space purification device, the chloride ion concentration in the aqueous solution is likely to decrease, and the generation amount of hypochlorous acid is not stable. The present disclosure has been made in view of the above problem, and an object thereof is to provide a space purification device capable of stably generating a desired amount of hypochlorous acid gas without externally supplying an aqueous solution containing chloride ions for a long period of time. The space purification device according to the present disclosure includes: an electrolysis tank configured to store a first aqueous solution containing chloride ions; a supply tank configured to store a second aqueous solution containing chloride ions at a higher concentration than the first aqueous solution and supply chloride ions to the first aqueous solution; an electrolysis tank-side anode and an electrolysis tank-side cathode each provided in the electrolysis tank; a supply tank-side cathode provided in the supply tank; an anion exchange membrane disposed between the electrolysis tank and the supply tank and capable of permeating anions based on a voltage applied between the electrolysis tank-side anode and the supply tank-side cathode; a non-barrier membrane electrolysis part provided in the electrolysis tank and subjecting the first aqueous solution to non-barrier membrane electrolysis to generate hypochlorous acid with a first current flowing between the electrolysis tank-side anode and the electrolysis tank-side cathode; a barrier membrane electrolysis part provided over the electrolysis tank and the supply tank and performing barrier membrane electrolysis via the anion exchange membrane with a second current flowing between the electrolysis tank-side anode and the supply tank-side cathode; and a current controller configured to control the second current to supplement chloride ions contained in the first aqueous solution and decreased in number through the non-barrier membrane electrolysis, allowing chloride ions contained in the second aqueous solution to permeate through the anion exchange membrane and be supplied to the first aqueous solution. According to the present disclosure, it is possible to provide a space purification device capable of stably generating a desired amount of hypochlorous acid gas without externally supplying an aqueous solution containing chloride ions for a long period of time. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view illustrating a space purification device according to a first exemplary embodiment.Fig. 2 is a front part cross-sectional view illustrating a space purification device according to a first exemplary embodiment.Fig. 3 is a block diagram showing a current controller according to a first exemplary embodiment.Fig. 4 is a front cross-sectional view illustrating a first modification of an electrolysis tank and a supply tank included in a space purification device according to a first exemplary embodiment.Fig. 5 is a front cross-sectional view illustrating a second modification of an electrolysis tank and a supply tank included in a space purification device according to a first exemplary embodiment.Fig. 6 is a schematic perspective view illustrating a space purification device according to a second exemplary embodiment.Fig. 7 is a schematic plan view illustrating a space purification device according to a second exemplary embodiment. DESCRIPTION OF EMBODIMENT Hereinafter, specific exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. The xyz coordinates in the right-handed system shown in the drawings are for the convenience of explaining the positional relationship of the components. Unless otherwise noted, the z-axis plus direction is vertically upward. The xy plane is the horizontal plane, which is common to the drawings. <First exemplary embodiment> Fig. 1 is a perspective view illustrating the outline of space purification device 1 according to the first exemplary embodiment. In space purification device 1, first aqueous solution L1 containing chloride ions is electrolyzed in electrolysis tank 10 described later, and