Water treatment device

Patent metadata

Field	Value
Publication number	US-10815134-B2
Application number	US-201716087469-A
Country	US
Kind code	B2
Filing date	Apr 24, 2017
Priority date	Jul 7, 2016
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

The water treatment device according to the present disclosure includes: an electrochemical cell having electrodes including a positive electrode and a negative electrode, and a bipolar membrane; a tank; a power supply configured to apply power to the electrodes; a water circulation flow path having at least the tank and the electrochemical cell and through which water circulates; a circulation device configured to circulate water in the water circulation flow path; a raw water supply path configured to supply raw water to the water circulation flow path; and a control device. In performing water softening treatment in the electrochemical cell where power is applied to the electrodes so as to remove ions from raw water and soft water is produced, the control device drives the circulation device so as to circulate water in the water circulation flow path.

First claim

The invention claimed is:

1. A water treatment device comprising:
an electrochemical cell having electrodes including a positive electrode and a negative electrode, and a bipolar membrane disposed between the positive electrode and the negative electrode;
a tank;
a power supply configured to apply power to the electrodes;
a water circulation flow path comprising the tank, an inlet port to the tank, an outlet port from the tank, and the electrochemical cell, and through which water circulates;
a circulator configured to circulate the water in the water circulation flow path;
a raw water supply path configured to supply raw water to the water circulation flow path;
a controller; and
a filter disposed in inside of the tank,
wherein, in performing water softening treatment in the electrochemical cell, power is applied to the electrodes so as to remove ions from the raw water and soft water is produced,
the controller drives the circulator so as to circulate the water in the water circulation flow path, and
the inlet port of the water circulation flow path to the tank is disposed on one side of the tank using the filter as a boundary, and the outlet port of the water circulation flow path to the tank is disposed on another side of the tank using the filter as the boundary.

2. The water treatment device according to claim 1 , further comprising:
a flow path switch disposed in a middle portion of the water circulation flow path; and
a soft water discharge path which is connected to the flow path switch and through which the soft water is discharged from inside of the flow path switch,
wherein
the flow path switch is configured to select either an operation of making the tank and the soft water discharge path communicate with each other or an operation of forming the water circulation flow path into a closed flow path, and
the flow path switch is also configured to discharge the soft water stored in the tank through the soft water discharge path when the tank and the soft water discharge path are made to communicate with each other.

3. The water treatment device according to claim 1 , further comprising:
a water drain path through which the water in the tank is drained; and
a scale suppressing agent supply path through which a scale suppressing agent is supplied into the tank,
wherein, in the electrochemical cell, in performing regeneration treatment of the bipolar membrane in which power is applied to the electrodes such that the electrodes have potentials reverse to potentials used in the water softening treatment, the controller allows the supply of the raw water and the scale suppressing agent into the tank and, at the same time, drives the circulator so as to circulate the water in the water circulation flow path and drains the water used for the regeneration treatment stored in the tank through the water drain path.

4. The water treatment device according to claim 1 , wherein the controller determines finishing of treatment based on a lapsed time from starting of the treatment or values of voltages applied to the electrodes in at least one of water softening treatment and regeneration treatment.

5. The water treatment device according to claim 1 , wherein the positive electrode and the negative electrode are disposed such that the positive electrode and the negative electrode face the bipolar membrane so as to sandwich the bipolar membrane between the positive electrode and the negative electrode, and the positive electrode and the negative electrode are disposed at positions where the positive electrode and the negative electrode fall within a projection area of the bipolar membrane.

6. The water treatment device according to claim 1 , wherein the positive electrode and the negative electrode are formed in a planar shape with a center portion, and first and second through holes are respectively disposed at the center portions of the positive and negative electrodes.

7. The water treatment device according to claim 3 , wherein flow straightening members are disposed in the water circulation flow path upstream of and downstream of the bipolar membrane respectively so as to sandwich the bipolar membrane by the flow straightening members, each of the flow straightening members being made of an insulating material and having a plurality of flow path apertures formed by a latticed member.

8. The water treatment device according to claim 3 , wherein power to be applied to the electrodes is intermittently supplied when regeneration treatment of the bipolar membrane is performed.

9. The water treatment device according to claim 1 , further comprising:
a water drain path configured to drain water in the tank,
wherein
the raw water supply path and the water drain path are vertically disposed upstream of and downstream of the tank, respectively, with the filter therebetween, and
the water which circulates in the water circulation flow path flows into the tank from the inlet port, passes the filter from a side of the filter facing the water drain path toward a side of the filter facing the raw water supply path and, thereafter, flows out from the outlet port to outside of the tank.

10. The water treatment device according to claim 1 , wherein an anion exchange group is disposed between one of the electrodes and the bipolar membrane and in a flow path of the water between said one of the electrodes and the bipolar membrane.

11. The water treatment device according to claim 1 , wherein a plurality of bipolar membranes are present, the water treatment device further comprising a spacer member disposed in a water flow path between the bipolar membranes,
wherein a vertical length of the spacer member is larger than a length of the bipolar membranes.

12. The water treatment device according to claim 1 , wherein a plurality of bipolar membranes are present, the water treatment device further comprising a spacer member disposed in a flow path of the water between the bipolar membranes,
wherein a horizontal length of the spacer member is smaller than a length of the bipolar membranes.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Sasabe Shigeru
• Tani Tomoko
• Ueya Noriyoshi
• Imai Kazuo
• Kitagawa Hiroaki

Classifications

• B01D2321/16

  Use of chemical agents · CPC title

• B01D61/46

  Apparatus therefor · CPC title

• B01D2311/22

  characterised by a specific duration or time · CPC title

• B01D2321/223

  Polarity reversal · CPC title

• B01D61/54

  Controlling or regulating · CPC title