Abstract: A cryogenic enhanced mechanical freezer system and method are provided. The disclosed system includes a mechanical freezer compartment adapted for freezing food products on a conveyor, a cryogen injection system adapted to directly inject cryogen into a shrouded zone proximate the conveyor in the mechanical freezer compartment, an exhaust system adapted to rapidly evacuate cryogen vapors from the freezer compartment; and a freezer control system adapted to operatively control the exhaust system and cryogen injection system in response to selected inputs so as to not adversely affect the mechanical refrigeration capacity associated with the mechanical freezer. The selected inputs may include user inputs as well as inputs received from one or more temperature sensors disposed in the freezer compartment and a gas analyzer adapted to monitor concentrations of selected gases within the freezer compartment.

Abstract: A cryogenic enhanced mechanical freezer system and method are provided. The disclosed system includes a mechanical freezer compartment adapted for freezing food products, a cryogen injection system adapted to directly inject cryogen into the mechanical freezer compartment, an exhaust system adapted to rapidly evacuate cryogen vapors from the freezer compartment; and a freezer control system adapted to operatively control the exhaust system and cryogen injection system in response to selected inputs. The selected inputs may include user inputs as well as inputs received from a temperature sensor disposed in the freezer compartment and a gas analyzer adapted to monitor concentrations of selected gases within the freezer compartment. Access to the freezer compartment is prevented during cryogen injection and when the atmosphere in the freezer compartment is not safe as determined by the gas analyzer.

Abstract: A liquid cryogen based blending system and method is provided. The disclosed embodiment of the system includes a liquid cryogen flow circuit, a heated fluid circuit, and a plurality of injectors or nozzles disposed adapted for injection of a liquid cryogen into or near a product to be cooled. The disclosed system and method also includes a controller adapted to operatively control the injection of liquid cryogen and concurrently control the flow warm fluid, such as nitrogen vapor, to and thru the plurality of injectors.

Abstract: The method of the invention is based on the comparison of local vapor concentrations at the inlet and outlet refrigeration ports and taking action based on that comparison. Control apparatus incorporating the invention is installed inside a refrigeration enclosure, adjacent to a port, preferably at the lowermost port. If the enclosure contains multiple ports at similar height, then each port has a form of the control apparatus attached to it. The control apparatus adjusts a flow of vapor leaving the interior of the enclosure. The control apparatus includes a duct assembly and a blower system. The bottom portion of the duct assembly is a tunnel enclosure through which a conveyor belt passes. Connected to an inside edge of the tunnel enclosure is a duct that extends upward from the conveyor belt. A blower for this duct either sucks vapor away from the conveyor belt or blows vapor from the enclosure interior toward the belt.