In situ sterilization and decontamination system using a non-thermal plasma discharge

Abstract

A sterilization and decontamination system in which a non-thermal plasma discharge device is disposed upstream of a suspension media (e.g., a filter, electrostatic precipitator, carbon bed). The plasma discharge device generates a plasma that is emitted through apertures (e.g., capillaries or slits) in the primary dielectric. Plasma generated active sterilizing species when exposed to contaminants or undesirable particulate matter is able to deactivate or reduce such matter in contaminated fluid stream and / or on objects. Thus, the undesirable contaminants in the fluid to be treated are first reduced during their exposure to the plasma generated active sterilizing species in the plasma region of the discharge device. Furthermore, the plasma generated active sterilizing species are carried downstream to suspension media and upon contact therewith deactivate the contaminants collected on the suspension media itself. Advantageously, the suspension media may be cleansed in situ. To increase the sterilization efficiency an additive, free or carrier gas (e.g., alcohol, water, dry air) may be injected into the apertures defined in the primary dielectric. These additives increase the concentration of plasma generated active sterilizing agents while reducing the byproduct of generated undesirable ozone pollutants. Downstream of the filter the fluid stream may be further treated by being exposed to a catalyst media or additional suspension media to further reduce the amount of undesirable particulate matter.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application (a) is a continuation-in-part of U.S. patent application Ser. No. 09 / 738,923, filed on Dec. 15, 2000, which claims the benefit of U.S. Provisional Application Nos. 60 / 171,198, filed on Dec. 15, 1999, and 60 / 171,324 filed on Dec. 21, 1999; and (b) claims the benefit of U.S. Provisional Application Nos. 60 / 336,866, filed on Nov. 2, 2001, and 60 / 336,868, filed on Nov. 2, 2001. All applications are hereby incorporated by reference in their entirety.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention is directed to a method and system for sterilization of air streams and decontamination of objects / surfaces and, in particular, to such a method and system using a non-thermal plasma discharge device or generator. [0004] 2. Description of Related Art [0005] Suspension media (e.g., filters, carbon beds, electrostatic precipitators) used in air handling equipment for ventilation purposes captu...

AI Technical Summary

Benefits of technology

The present invention is a method and system for sterilizing and decontaminating fluids and objects using non-thermal plasma generated by a plasma discharge device. The process involves the production of biologically active species that are short-lived and able to quickly decompose, resulting in minimal health and environmental hazards. The addition of organic compounds or other additives can enhance the efficiency of the process. The use of a dielectric capillary or dielectric slit configuration allows for efficient transport of the active sterilizing species to contaminated areas. The system includes a plasma discharge device with a primary dielectric and at least one aperture for the passage of plasma. The contaminated fluid is then exposed to the generated active sterilizing species, and particulate matter is collected and cleansed from the filter. The technical effects of the invention include improved sterilization efficiency, reduced health and environmental hazards, and the ability to deactivate pathogens by promoting the replacement of a hydrogen atom in bacterial DNAs.

Problems solved by technology

Over a period of use, undesirable contaminants become trapped and collect in the suspension media thereby degrading its performance and becoming a concentrated source of bio-hazards for a ventilation system.

Either of these conventional methods for disposal of the contaminants involve a high potential that some of the captured spores, pathogens, and other undesirable particulate matter may be released into the atmosphere.

This is particularly important in hazardous areas such as hospitals, laboratories, operating rooms that are exposed to extremely hazardous pathogens (e.g., tuberculosis, small pox, anthrax) or other contaminants in which minimal concentrations can generate considerable deleterious health consequences if released through a ventilation system.

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