US-12622440-B2 - Food and fresh produce disinfection chamber utilizing fast mixed liquid and nonequilibrium plasma-generated species

US12622440B2US 12622440 B2US12622440 B2US 12622440B2US-12622440-B2

Abstract

A device for creating reactive oxygen and reactive nitrogen species comprising: a plasma generator comprising at least one electrode positioned within an open-ended chamber and a centrifugal mixing chamber in fluid communication with the plasma generator, said centrifugal mixing chamber comprising a mixing chamber side wall and a blade, said blade oriented to allow passage of air in a circular motion around a central post of said centrifugal mixing chamber, and an exit nozzle on an opposing end of said centrifugal mixing chamber.

Inventors

Gregory Fridman
Randy Richard Cox
Charles Christopher Bailey, III

Assignees

AA PLASMA LLC

Dates

Publication Date: 20260512
Application Date: 20210528

Claims (14)

1 . A device for creating charged microdroplets comprising: a centrifugal mixing chamber for receiving atomized microdroplets, a plasma generator comprising at least one electrode positioned within an open-ended chamber; wherein said centrifugal mixing chamber comprises a central post and a blade structure defining a centrifugal path around the central post to orient a flow of air and microdroplets from one end of the centrifugal mixing chamber to a second end.
2 . The device of claim 1 wherein the plasma generator is positioned before the centrifugal mixing chamber.
3 . The device of claim 2 wherein said open-ended chamber having a first end and a second end, with the first end and the second end open to allow passage of air through the open-ended chamber; an air filter positioned at the first end; and an atomizing cavity having a first cavity end in fluid contact with the second end, a second cavity end, and a side wall, said side wall comprising at least one aperture thereto, and at least one nozzle affixed into said aperture; wherein the centrifugal mixing chamber is contiguous with the second cavity end, said centrifugal mixing chamber comprising a mixing chamber side wall and the blade, said blade oriented to allow a passage of air in a circular motion around the central post of said centrifugal mixing chamber, and an at least one exit nozzle on an opposing end of said centrifugal mixing chamber.
4 . The device of claim 1 wherein the plasma generator is positioned after the centrifugal mixing chamber.
5 . The device of claim 4 comprising an atomizing cavity in contact with the centrifugal mixing chamber, said atomizing cavity comprising a first cavity end and a second cavity end, and a side wall, said side wall comprising at least one aperture thereto, and at least one nozzle affixed into said aperture; wherein the centrifugal mixing chamber is contiguous with the second cavity end, said centrifugal mixing chamber comprising a mixing chamber side wall and the blade, said blade oriented to allow passage of air in a circular motion around the central post of said centrifugal mixing chamber, and an at least one exit nozzle on an opposing end of said centrifugal mixing chamber, which is in contact with the plasma generator.
6 . The device of claim 1 further comprising a fan.
7 . The device of claim 6 wherein the fan pulls air through an air filter.
8 . The device of claim 1 further comprising a pump and a fluid vessel, said pump configured to pump fluid through at least one nozzle.
9 . The device of claim 8 wherein said pump generates nebulized fluid.
10 . The device of claim 8 wherein the pump is disposed of below the centrifugal mixing chamber.
11 . The device of claim 10 wherein the pump is placed between 0.01 meter and 3 meters below the centrifugal mixing chamber.
12 . The device of claim 8 further comprising a drain.
13 . The device of claim 12 wherein the drain connects to either the fluid vessel or is disposed.
14 . The device of claim 1 wherein said plasma generator comprises at least two electrodes stacked on top of one another, wherein the two electrodes are positioned to allow the flow of air above and below each of the two electrodes within the open-ended chamber.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 371 National Phase Entry of International Patent Application No. PCT/US2021/070632 filed on May 28, 2021, which claims the benefit of U.S. Provisional Patent Application No. 62/704,820 filed on May 29, 2020, with the United States Patent and Trademark Office, the contents of which are incorporated herein by reference in their entirety. FIELD OF THE INVENTION The present invention is related to devices for sanitization, disinfection, and/or sterilization of fresh produce, meat, poultry, fish, and other perishable materials utilizing plasma generated radicals in fluid, as well as methods of use of the same with devices and in enclosed environments such as refrigeration containers. BACKGROUND OF THE INVENTION As soon as produce is harvested, there is a rush to cool the produce to maintain freshness. Chilling the produce to just above freezing dramatically increases the shelf life of the produce after harvest, as compared to produce that is not chilled. This is most apparent for vegetables as compared to whole fruits, as whole fruits typically have shells intended to protect the fruit (imagine an apple) once it is separated from the parent plant, whereas vegetables are literally a portion of the parent plant (i.e., lettuce). The same issue is found with meats including red and white meats as well as poultry, and also with fish. Red meat produce is slaughtered and then exsanguinated before being butchered into particular cuts of meat. This process is similar for pork, lamb, and other non-beef meats. Poultry also utilizes a similar process, though there are additional processing steps for feather removal. In each case, these types of meat are frequently ground, cut, or otherwise handled with or without skin and these various handling steps provide opportunity for introduction of vegetative bacteria, viruses, bacterial or fungal spores, and the like, which can spoil the food. Topical materials like sodium hypochlorite are frequently added to meats to inactivate pathogenic organisms on the meat for storage and human consumption, in order to increase the safety of consuming these meats in their refrigerated or frozen states. Fish, both freshwater and saltwater varieties, face similar hurdles in processing. In longline fishing, most fish are flash frozen once they are caught in order to maximize the meat quality and freshness to 0° F. or even to −20° F. or lower. For farmed fish, the process may or may not include this flash freezing step, and instead may simply gut and sell the materials as fresh. In either case, there remains a goal to reduce or eliminate the introduction of bacteria or viruses to the fish to ensure that it is safe for later human consumption. Accordingly, like meat, certain preservatives and sterilizing compounds are added to prevent attack by viral, bacterial, and fungus. New devices and processing strategies are needed, which are more efficient and use fewer chemicals than present strategies. Applicant has created a novel device and method of treating whole and cut produce, meats, poultry, fish, and other perishable items utilizing plasma dissolved within microdroplets of fluid. SUMMARY OF THE INVENTION The present disclosure details a new device for generating reactive oxygen and nitrogen species using cold plasma, which are combined with microdroplets of fluid, wherein the reactive oxygen and nitrogen species are dissolved into the microdroplets, which conserves and protects these highly unstable and reactive species and wherein the microdroplets are then expressed into a container or onto the materials to coat perishable items such as produce to sanitize, disinfect, and/or sterilize the perishable items. Advantageously, in certain embodiments, the devices detailed herein can utilize vacuum containers wherein when the vacuum is terminated, the rush of air through a valve is utilized to move the reactive species, generated in plasma, and to circulate charged microdroplets into the vacuum container. In a preferred embodiment, a device for creating charged microdroplets comprising: a centrifugal mixing chamber for receiving atomized microdroplets, a plasma generator comprising at least one electrode positioned within an open-ended chamber; wherein said centrifugal mixing chamber comprises a blade to orient a flow of air and microdroplets from one end of the centrifugal mixing chamber to a second end. In a further preferred embodiment, the device wherein the plasma generator is positioned before the centrifugal mixing chamber. In a further preferred embodiment, the device wherein the plasma generator is positioned after the centrifugal mixing chamber. In a further preferred embodiment, the device wherein said open-ended chamber having a first end (16) and a second end (17), with the first end and the second end open to allow passage of air through the open-ended chamber; an air filter positioned at the first end; and an atomizing cavity