Method of purifying water

• US 4,098,660 A
• Filed: 06/28/1977
• Issued: 07/04/1978
• Est. Priority Date: 06/09/1973
• Status: Expired due to Term

• Current Assignee: Sachs-Systemtechnik GmbH
• Original Assignee: Sachs-Systemtechnik GmbH
• Inventors: Eibl, Volker, Reis, August
• Primary Examiner(s): Prescott, Arthur C.
• Application Number:
  US05/810,867
• Time in Patent Office: 371 Days
• Field of Search: 204/149, 204/151, 204/180 P, 204/130, 426/321
• US Class Current: 205/701
• CPC Class Codes: A61L 2/035 Electrolysis
• CPC Class Codes: C02F 1/4606 for producing oligodynamic substances to disinfect the water
• CPC Class Codes: C02F 1/4672 by electrooxydation
• CPC Class Codes: C02F 2303/04 Disinfection

Abstract

Water contaminated with pathogenic microorganisms is passed over a silver anode of an electrolyte cell in a layer 1 to 4 mm thick. The anode surface and the rate of water flow through the cell are related according to the equation F ≧ c × V, wherein F is the anode surface area in cm², V is the water flow rate in cm³ /second and c is a constant of the dimension sec/cm, with a value of 2 to 5. The density of the current in relation to the area of the anode surface is between 1.5 and 3.0 mA/cm² and the voltage is such that active oxygen is generated at the anode. The effluent from the cell is safe to drink.

Claims

1. A method of purifying water contaminated with microorganisms and having a specific resistance of approximately 0.5 ×

10³ ohm ·

cm to approximately 6.6 ×

10³ ohm ·

cm which comprises;

(a) passing a stream of said water over a surface of conductive, silver-containing material,

(1) the thickness of said stream at right angles to said surface being not greater than 4 millimeters; and

(b) passing direct electric current between said surface as an anode and said contaminated water at a density of 1.5 to 3.0 mA per square centimeter of said surface,

(1) the area F of said surface in square centimeters and the flow rate V of said stream in cm³ /second satisfying the relationship F ≧

c ×

V, wherein c is a factor whose numerical value, in sec/cm, is at least equal to the numerical value of said thickness, in millimeters, plus one.

2. A method as set forth in claim 1, wherein said thickness is at least 1 mm.

3. A method as set forth in claim 2, wherein said direct electric current is generated by establishing a potential between said surface and said water sufficient to generate active oxygen at said surface.

4. A method as set forth in claim 2, wherein said thickness is not greater than 2 mm.

5. A method as set forth in claim 2, wherein the surface of said material contains at least 99% silver.

6. A method as set forth in claim 2, wherein said current is passed to said contaminated water from a surface of a cathode bounding said stream in a direction perpendicular to said surface of silver-containing material.

7. A method as set forth in claim 2, wherein said density is approximately 2.7 mA per square centimeter of said surface.

8. A method as set forth in claim 2, wherein turbulence is generated in said stream, said surface being substantially planar.

9. A method as set forth in claim 2, wherein said current is passed to said contaminated water from a cathode through a selectively permeable diaphragm bounding said stream in a direction perpendicular to said surface of silver-containing material.

10. A method as set forth in claim 1, wherein said numerical value of said factor c is not substantially greater than said numerical value of said thickness, in millimeters, plus one.