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A product is chilled or at least partially frozen by descending against a counter-current flow of liquid nitrogen in a vertical freezer containing an immersion bath of liquid nitrogen and the chilled or at least partially frozen product is extracted from the bath. The product may optionally be a liq

A product is chilled or at least partially frozen by descending against a counter-current flow of liquid nitrogen in a vertical freezer containing an immersion bath of liquid nitrogen and the chilled or at least partially frozen product is extracted from the bath. The product may optionally be a liquid, semi-solid, suspension or slurry.

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1. A method for chilling or at least partially freezing product in an immersion freezer containing a bath of liquid nitrogen, the bath of liquid nitrogen being contained within an insulated immersion bath tank, said method comprising the steps of: depositing, with a material feeder, a feed of the pr

1. A method for chilling or at least partially freezing product in an immersion freezer containing a bath of liquid nitrogen, the bath of liquid nitrogen being contained within an insulated immersion bath tank, said method comprising the steps of: depositing, with a material feeder, a feed of the product to be chilled or frozen onto a surface of the liquid nitrogen bath;allowing the deposited product to descend down through the bath against a counter-current flow of liquid nitrogen through the bath to produce chilled or at least partially frozen product; andextracting the chilled or at least partially frozen product from the bath, wherein: the tank has one or more suction ports disposed at an upper region of said tank that fluidly communicate with one or more injection ports that are disposed within an interior of the tank; andliquid nitrogen is received from said one or more suction ports and injected straight up through the interior of the tank via said one or more injection ports so as to create said counter-current flow of liquid nitrogen. 2. The method of claim 1, wherein the product is a liquid, semi-solid, suspension or slurry. 3. The method of claim 1, wherein the product is solid. 4. The method of claim 1, wherein the product is selected from the group consisting of: a chemical suspension, slurry or solution; a liquid, semi-solid or solid pharmaceutical product; a liquid, semi-solid or solid foodstuff; and a liquid, semi-solid or solid food additive. 5. The method of claim 1, wherein said step of extracting the product comprises the steps of: opening an upper isolation valve in fluid communication with a bottom interior region of a tank containing the liquid nitrogen bath;allowing a slug of liquid nitrogen and the product to empty out of the tank and into an intermediate container via the open upper isolation valve, the slug being prevented from flowing down out of the intermediate container by a closed lower isolation valve;closing the upper isolation valve;opening the lower isolation valve to allow the slug to flow down out of the intermediate container. 6. The method of claim 1, wherein said step of extracting the product comprises the step of continuously operating a valve fluidly communicating with a bottom interior of a tank containing the liquid nitrogen immersion bath to place said continuously operated valve in succeeding ones of a plurality of positions, wherein each position allows an amount of liquid nitrogen and product to empty from the tank, wherein said valve is a butterfly, gate, or rotary valve. 7. The method of claim 1, wherein said step of extracting the product comprises the steps of: rotating an auger screw having a bottom end that extends into a bottom interior region of a tank containing the liquid nitrogen immersion bath to convey liquid nitrogen and product from the bottom interior region to a top of the auger screw; andallowing the conveyed liquid nitrogen and product to cascade off of the top of the auger screw. 8. A method for chilling or at least partially freezing product in an immersion freezer containing a bath of liquid nitrogen, said method comprising the steps of: depositing the product to be chilled or frozen onto a surface of the liquid nitrogen bath;allowing the deposited product to descend down through the bath against a counter-current flow of liquid nitrogen through the bath to produce chilled or at least partially frozen product; andextracting the chilled or at least partially frozen product from the bath, wherein the counter-current flow is produced by pumping liquid nitrogen with a pump into an injection port comprising a vertical tube that is disposed within a bottom interior portion of a tank containing the bath and liquid nitrogen is recirculated from a top region of the tank via one or more suction portions and to a suction inlet of the pump. 9. The method of claim 8, further comprising the step of changing a residence time of the product within the immersion bath by changing a speed of the pump. 10. A vertical liquid nitrogen immersion freezer, comprising: an insulated immersion bath tank adapted and configured to contain an immersion bath of liquid nitrogen;a material feeder operatively associated with said immersion bath tank to deliver a feed of product to the liquid immersion bath contained within said immersion bath tank for chilling or at least partially freezing the product;a pump or propeller system;one or more injection ports fluidly communicating with an outlet side of said pump or propeller system via a feed line extending through a wall of said immersion bath tank, said one or more injection ports being disposed within an interior receiving liquid nitrogen from the pump and being adapted and configured to inject liquid nitrogen straight up through the interior of said immersion bath tank; andone or more suction ports disposed at an upper region of said immersion bath tank and fluidly communicating between an interior of said immersion bath tank and a return line that fluidly communicates with a suction inlet side of said pump or propeller system, said one or more suction ports withdrawing liquid nitrogen from said immersion bath tank through operation of said pump or propeller system and directing the withdrawn liquid nitrogen into said return line. 11. The freezer of claim 10, wherein said immersion bath tank has a tubular configuration that is tapered inwardly towards a bottom region of said immersion bath tank. 12. The freezer of claim 11, further comprising a sleeve concentrically disposed within an upper region of said immersion bath tank that tapers inwardly towards a bottom of said sleeve, an annular space being formed in between said sleeve and an inner surface of said immersion bath tank, wherein said material feeder is positioned to feed the product inside said sleeve and not outside of said sleeve. 13. The freezer of claim 10, wherein the material feeder is selected from a group consisting of a conveyor, a slide plate, a drip tray, and an injector. 14. The freezer of claim 10, wherein said one or more injection ports essentially consist of a single injection port disposed at a bottom region of said immersion bath tank. 15. The freezer of claim 10, further comprising a surge/storage tank in fluid communication between said return line and said pump or propeller system. 16. The freezer of claim 10, further comprising an extraction system adapted and configured to extract product from a bottom region of said immersion bath tank. 17. The freezer of claim 16, wherein said extraction system comprises: a tubular section fluidly communicating with a bottom interior region of said immersion bath tank; anda valve disposed at a downstream end of said tubular section, said valve being adapted and configured to be continuously operated to continuously allow slugs of the product and the liquid nitrogen to empty out of said tubular section, the valve being a butterfly valve, a gate valve, or a rotary valve. 18. The freezer of claim 16, wherein said extraction system comprises an auger screw extending down at an angle into an interior bottom region of said immersion bath tank, and a porous conveyor belt disposed below a top of said screw. 19. The freezer of claim 16, further comprising a recovery tank operatively associated with said extraction system adapted and configured to capture the liquid nitrogen from combined liquid nitrogen and product that is extracted by said extraction system and a return line in fluid communication between said recovery tank and the suction inlet of said pump or propeller system. 20. The freezer of claim 10, wherein: an extraction system comprises an upper isolation valve and a lower isolation valve in fluid communication on either side of an intermediate container;said upper isolation valve has an open position allowing fluid communication between the interior bottom region of said immersion bath tank and said intermediate container and a closed position blocking fluid communication between an interior bottom region of said immersion bath tank and said intermediate container;said lower isolation valve has an open position allowing the product and the liquid nitrogen to empty out of said intermediate container and a closed position preventing the product and the liquid nitrogen from emptying out of said intermediate container.