Process for the reduction of biofouling using electric fields

• US 7,931,813 B2
• Filed: 12/14/2007
• Issued: 04/26/2011
• Est. Priority Date: 12/14/2007
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Montasser, Yuseph, Chokshi, Setu, Tayalia, Yatin, Polizzotti, David M., Asokan, Thangavelu
• Primary Examiner(s): Griffin; Walter D
• Assistant Examiner(s): Allen; Cameron J
• Application Number:
  US11/956,561
• Publication Number:
  US 20090152207A1
• Time in Patent Office: 1,229 Days
• Field of Search: 205/740, 205/722, 210/748, 210/760, 210/600
• US Class Current: 210/748.01
• CPC Class Codes: A61L 2/02 using physical phenomena
• CPC Class Codes: C02F 1/32 with ultraviolet light
• CPC Class Codes: C02F 1/44 by dialysis, osmosis or reverse osmosis general membrane separation processes B01D61/00, membrane modules B01D63/00, electrodialysis C02F1/4693, combination of membrane modules and bioreactors C02F3/1268
• CPC Class Codes: C02F 1/4608 using electrical discharges
• CPC Class Codes: C02F 1/48 with magnetic or electric fields C02F1/46 takes precedence
• CPC Class Codes: C02F 1/50 by addition or application of a germicide or by oligodynamic treatment C02F1/4606, C02F1/467, C02F1/76 take precedence
• CPC Class Codes: C02F 1/72 by oxidation C02F1/4672 takes precedence
• CPC Class Codes: C02F 2001/46138 Electrodes comprising a substrate and a coating
• CPC Class Codes: C02F 2103/023 Water in cooling circuits
• CPC Class Codes: C02F 2201/46125 Electrical variables
• CPC Class Codes: C02F 2201/4615 Time
• CPC Class Codes: C02F 2201/46175 Electrical pulses
• CPC Class Codes: C02F 2201/4619 Supplying gas to the electrolyte gas diffusion electrodes C02F2001/46166
• CPC Class Codes: C02F 2303/04 Disinfection
• CPC Class Codes: C02F 2303/06 Sludge reduction, e.g. by lysis
• CPC Class Codes: C02F 2303/20 Prevention of biofouling

Abstract

A process to reduce or prevent biofouling, by destroying or deactivating microbiological content of feedwater, or other liquid, prior to its entrance into membranes or process equipment, such as heat transfer equipment. The process comprises the use of electrical discharge and/or electric fields to destroy microbes that result in the biofouling of surfaces. By destroying the microbiological content of the water the microbiology no longer is able to create a restricting biofilm upon or within said process equipment.

Claims

1. A process for the reduction of biofouling on surfaces of process equipment in an industrial aqueous system, comprising pretreating the water by subjecting the water to electrical discharges comprised of microsecond or sub-microsecond pulses to destroy or deactivate microbial matter by perforating cells, wherein said surfaces of process equipment comprises at least one of:

surface of water filtration membrane and heat transfer surface, the process further comprising the introduction of air or gas bubbles in the water, wherein the air or gas bubbles are injected through the tip of electrodes.

2. The process according to claim 1 wherein one or more electrode tips may be located at the air/water interface, or at the surface of a water column.

3. The process according to claim 2 wherein an electrode surface may be covered by a dielectric or insulation so that only a small portion of the electrode tip is exposed to the water.

4. The process of claim 1 wherein the process is applied to potentiate activity of a biocide, that further comprises the addition of biocides, disinfectants or combinations thereof to the water subsequent to the electrical discharge process but prior to entering process equipment.

5. The process of claim 1, wherein the industrial aqueous system has a characteristic residence or transit time, and the process is effective to deactivate or stun viable biomatcrial for said characteristic residence or transit time.

6. The process according to claim 1, wherein water filtration membrane comprises microfilter, nanofilter, ultrafilter, or reverse osmosis membrane.

7. The process according to claim 1, wherein said industrial aqueous system comprises open recirculating cooling water system, pulping and papermaking system, water transport pipeline, closed cooling system, reverse osmosis system, air washer system, shower water system, once-through water system, hydrocarbon storage system, hydrocarbon transport pipeline, metalworking fluid system, or aqueous mineral processing system.