Method and apparatus for neutralizing electrochemically activated liquids

• US 8,337,690 B2
• Filed: 10/03/2008
• Issued: 12/25/2012
• Est. Priority Date: 10/04/2007
• Status: Active Grant

• Current Assignee: Tennant Company
• Original Assignee: Tennant Company
• Inventors: Field, Bruce F.
• Primary Examiner(s): Hendricks, Keith
• Assistant Examiner(s): Friday, Steven A.
• Application Number:
  US12/245,213
• Publication Number:
  US 20090095639A1
• Time in Patent Office: 1,544 Days
• Field of Search: 204/263, 204/275.1, 205/349, 205/687, 205/701, 205/742, 205/746, 205/766, 134/10, 134/21, 134/58.R, 134/198
• US Class Current: 205/687
• CPC Class Codes: A47L 11/30 by suction
• CPC Class Codes: A47L 11/4016 specially adapted for collecting fluids
• CPC Class Codes: A47L 11/4022 with means for recycling the dirty liquid treatment of waste water C02F
• CPC Class Codes: B08B 3/14 Removing waste, e.g. labels, from cleaning liquid; Regenerating cleaning liquidstreatment of water in general C02F
• CPC Class Codes: C02F 1/4618 for producing "ionised" acidic or basic water
• CPC Class Codes: C02F 1/4672 by electrooxydation
• CPC Class Codes: C02F 1/4676 by electroreduction
• CPC Class Codes: C02F 2201/008 Mobile apparatus and plants, e.g. mounted on a vehicle
• CPC Class Codes: C02F 2201/46115 Electrolytic cell with membranes or diaphragms
• CPC Class Codes: C02F 2201/46175 Electrical pulses
• CPC Class Codes: C02F 2209/04 Oxidation reduction potential [ORP]
• CPC Class Codes: C02F 2303/185 The treatment agent being halogen or a halogenated compound

Abstract

A method and apparatus are provided for reducing an oxidation-reduction potential (ORP) of an electrochemically activated liquid. The ORP is reduced by emitting ions from an ion generator into the electrochemically activated liquid, wherein the ions have a charge polarity that is opposite to the ORP of the liquid.

Claims

1. A method comprising:

providing at least one of an acidic liquid having a positive oxidation reduction potential or an alkaline liquid having a negative oxidation reduction potential;

dispensing at least one of the acidic liquid or the alkaline liquid to a surface as a dispensed liquid;

using the dispensed liquid as a working liquid in at least one of a cleaning or sanitizing operation;

recovering at least a portion of the dispensed liquid from the surface; and

treating the recovered liquid by applying an electric potential to an electrode, wherein the electric potential is negative if the oxidation reduction potential of the recovered liquid being treated is positive and the electric potential is positive if the oxidation reduction potential of the recovered liquid is negative, so as to generate ions in the recovered liquid that reduce the magnitude of the oxidation reduction potential.

2. A method comprising:

providing at least one of an acidic liquid having a positive oxidation reduction potential (ORP) of at least +800 millivolts or an alkaline liquid having a negative ORP of less than −

400 millivolts;

dispensing at least one of the acidic liquid or the alkaline liquid to a surface as a dispensed liquid;

using the dispensed liquid as a working liquid in at least one of a cleaning or sanitizing operation;

recovering at least a portion of the dispensed liquid from the surface; and

treating the recovered liquid by applying an electric potential to an electrode, wherein the electric potential is negative if the ORP of the recovered liquid being treated is positive and the electric potential is positive if the ORP of the recovered liquid being treated is negative so as to generate ions in the recovered liquid that neutralize the ORP of the recovered liquid being treated to a range of +50 millivolts to −

50 millivolts.

3. The method of claim 2, wherein the step of providing comprises generating the at least one of the acidic liquid or the alkaline liquid with an electrolysis cell.

4. The method of claim 2 and further comprising:

physically contacting the electrode with the recovered liquid during the step of applying an electric potential.

5. The method of claim 4, wherein the electrode extends through a wall of a container containing the recovered liquid.

6. The method of claim 2 and further comprising:

producing the acidic liquid and the alkaline liquid with an electrolysis cell;

delivering the acidic liquid and the alkaline liquid to respective first and second outlets of a platform supporting the electrolysis cell, wherein one of the first or second outlets is a working outlet and the other is a waste outlet;

performing the step of dispensing from the working outlet;

placing the recovered liquid in a recovery tank on the platform, which is coupled to the waste outlet; and

performing the step of applying the electric potential on the platform, the electrode being positioned in a flow path between the electrolysis cell and the waste outlet.

7. The method of claim 3, wherein the step of generating is performed on a platform that is selected from the group consisting of a mobile surface cleaner, a wall-mount platform, a floor-mount platform, a table-top platform and a hand-held platform.

8. The method of claim 2 and further comprising:

dispensing the dispensed liquid from a mobile surface cleaner to a surface and recovering the portion of the dispensed liquid from the surface by a recovery device carried by the cleaner;

placing the recovered portion of the liquid in a recovery tank carried by the cleaner; and

performing the step of applying the electric potential to the electrode to generate ions in the recovered liquid on the cleaner.

9. An apparatus comprising:

a mobile surface cleaner;

a dispenser, which is configured to dispense at least one of an acidic liquid having a positive oxidation reduction potential or an alkaline liquid having a negative oxidation reduction potential from the cleaner to a surface as a dispensed liquid;

a recovery device carried by the cleaner, which recovers a portion of the dispensed liquid from the surface;

a recovery tank for containing the portion of the liquid recovered from the surface;

liquid flow paths from the recovery device to the recovery tank and from the recovery tank to an outlet of the cleaner; and

an ion generator comprising an electrode positioned to generate the ions in the recovered portion of the liquid onboard the cleaner when the electrode is energized by an electric potential applied to the electrode by the ion generator, wherein the electric potential is negative if the oxidation-reduction potential of the recovered liquid is positive or the electric potential is positive if the oxidation-reduction potential of the recovered liquid is negative so that the ions generated in the recovered liquid at least partially neutralize the oxidation reduction potential of the recovered liquid.

10. The apparatus of claim 9 and further comprising:

an electrolysis cell onboard the mobile surface cleaner, which generates the at least one acidic liquid or alkaline liquid and has first and second liquid outputs, wherein the electrode is coupled in a flow path from one of the first and second outputs.

11. The apparatus of claim 9, wherein the electrode is positioned to physically contact the recovered liquid.

12. The apparatus of claim 11, wherein the electrode extends through a wall of the recovery tank.

13. The apparatus of claim 9, wherein the electrode is positioned to generate the ions along at least one of the liquid flow paths.

14. The apparatus of claim 9 and further comprising:

an electrolysis cell carried by the mobile surface cleaner and having an acid output flow path and an alkaline output flow path, wherein one of the acid and alkaline flow paths is coupled to the dispenser.

15. The apparatus of claim 14, wherein the other of the acid and alkaline flow paths is coupled to the recovery tank.

16. The apparatus of claim 9, wherein the ion generator consists of a single electrode.

17. The apparatus of claim 9, wherein the ion generator lacks a further electrode of opposite polarity as the electrode on which the electrical potential is applied.