Apparatus and method of purifying water with ozone

• US 6,673,248 B2
• Filed: 08/02/2002
• Issued: 01/06/2004
• Est. Priority Date: 02/02/2000
• Status: Expired due to Fees

• Current Assignee: S C Trade & Consult AB
• Original Assignee: S C Trade & Consult AB
• Inventors: Chowdhury, Sudhir
• Primary Examiner(s): Cecil, Terry K.
• Application Number:
  US10/182,758
• Publication Number:
  US 20030000896A1
• Time in Patent Office: 522 Days
• Field of Search: 210/192, 210/96.1, 210/760, 210/764, 210/739-746, 210/767, 422/186.07
• US Class Current: 210/739
• CPC Class Codes: B01F 23/2326 adding the flowing main component by suction means, e.g. using an ejector
• CPC Class Codes: B01F 23/237613 Ozone
• CPC Class Codes: B01F 25/3121 with additional mixing means other than injector mixers, e.g. screens, baffles or rotating elements
• CPC Class Codes: B01F 25/4231 using baffles
• CPC Class Codes: C02F 1/78 with ozone C02F1/4672 takes precedence
• CPC Class Codes: C02F 2103/003 Wastewater from hospitals, laboratories and the like, heavily contaminated by pathogenic microorganisms

Abstract

A method for purifying a flow of water, by eliminating any Legionella bacteria present therein using (a) an ozone generator, (b) an ozone injector for injecting ozone into the flow of water, (c) a mixing chamber for mixing the ozone with the flow of water; (d) an outlet for the flow of water, and (e) an electronic controller for the operation thereof: wherein the mixing chamber is of an inner geometry such as to create turbulence in the flow of water therein.

Claims

1. A method for purifying a flow of water in a water flow line by use of an apparatus comprising

(a) means for providing a flow of an ozone-containing gas;

(b) means for introducing the flow of the ozone-containing gas into the flow of water;

(c) a mixing chamber for turbulent mixing of the ozone-containing gas with the flow of water, located on the water flow line in the vicinity of

(d) an outlet for the flow of water; and

(e) electronic control means adapted to control the operation of said apparatus, thereby providing a flow of water which on exiting through the outlet for the water flow is essentially free from residual ozone and from contamination by Legionella bacteria wherein the ozone-containing gas is introduced into the flow of water so as to maintain

(i) a concentration of ozone in the water within the mixing chamber of about 0.01-0.5 mg/l; and

(ii) a contact time between the ozone-containing gas and the water that is essentially equal to the time of continuous flow of the water flow from a water inlet of the mixing chamber to the outlet for the water.

2. A method according to claim 1 wherein the mixing chamber comprises at least two baffles.

3. A method according to claim 2 wherein the baffles extend from an inner wall of the chamber in a direction essentially opposite to each other and essentially perpendicular to the flow of water.

4. A method according to claim 1 wherein the mixing chamber has the general form of a venturi tube.

5. A method according to claim 1, wherein surfaces inside of the mixing chamber that are susceptible of contact with the water flow are made of a material that is essentially inert towards ozone.

6. A method according to claim 1, wherein surfaces inside of the mixing chamber that are susceptible of contact with the water flow are made of a material having a catalytic activity.

7. A method according to claim 1, wherein the apparatus comprises a filter unit located downstream of the mixing chamber, which filter unit is capable of eliminating any residual ozone and/or particles such as killed Legionella bacteria from the water flow.

8. A method according to claim 7, wherein the filter unit comprises a metal oxide on a plate of activated carbon.

9. The method according to claim 8 wherein the metal oxide is manganese dioxide.

10. A method according to claim 1, wherein an electrolytic chamber regulates the pH of the water flow to a desired value.

11. A method according to claim 1, wherein the contact time between the ozone-containing gas and the flow of water is less than one second.

12. The method according to claim 1 wherein the water flow line is in a tap, a shower head, or a shower handpiece.