Abstract: An apparatus and method for spraying a cryogen in which a heat load is sprayed with a cryogen from one or more spray nozzles within a spray zone. A heat conductive element is positioned below the article and is provided with a surface sized to catch the liquid content of the cryogen that has been oversprayed, thereby to vaporize the overspray through direct heat transfer with the conductive element. In another aspect the present invention provides an apparatus and method in which a flow network a flow of a liquid cryogen is divided into first and second subsidiary streams. The second subsidiary stream is vaporized within a branch of the network and then mixed back into the first subsidiary stream to produce a two phase flow of the cryogen. The cryogen is then sprayed as the two phase flow. The flow rate of the second subsidiary stream can be controlled with a proportional valve to adjust the quality of the cryogen being sprayed so that pooling of overspray on said heat conductive element is inhibited.

Abstract: A method and apparatus of mixing liquid oxygen and liquid nitrogen to form a liquid mixture in which such streams are passed through a parallel flow heat exchanger in order to form a subcooled liquid oxygen stream and a partly vaporized liquid nitrogen stream both having the same temperature. The partly vaporized liquid nitrogen stream is phase separated in a phase separator to form liquid and vaporized nitrogen phases. The liquid phase stream composed of the liquid nitrogen is mixed with the subcooled liquid oxygen stream, preferably in a mixing tee, in order to form the desired mixture.

Abstract: An impingement freezer having a zoned freezing chamber in which the temperature of each zone is independently controllable so that the temperature profile within the impingement freezer is coldest at a zone adjacent the outlet and warmest at a zone adjacent the inlet for maximum thermodynamic usage of the refrigerant. Additionally, the velocity of each of the impingement jets is independently adjustable from zone to zone so that in the zone adjacent the entrance of the freezing chamber, the impingement jets can be adjusted to have maximum velocity to produce maximum heat transfer coefficients and thereby an acceptable rate of cooling within the impingement jet freezer. Impingement jets are formed within nozzles that are tapered in two orthogonal directions to prevent frost build-up. Circulation within the impingement jet freezer is produced by venturi-like devices driven by vaporization of incoming refrigerant.

Abstract: A method of cooling a liquid process fluid in which a liquid process stream is formed from the liquid process fluid and the process fluid contained within the liquid process stream is frozen into a conveyable particulate form. The conveyable particulate form is introduced back into the liquid process fluid. The liquid process fluid can be contained within a container and pumped through a pipe connected to the container to form the liquid process stream. A freezing chamber connected to the top of the container can be provided to countercurrently directly exchange heat between rising vaporized coolant and descending liquid process fluid. The resultant conveyable particulate form can be metered by provision of a valve.

Abstract: A level detector for detecting a level of a liquid is provided with an elongated probe having opposed proximal and distal ends. In use, the distal end of the elongated probe is submerged beneath the level of the liquid with an unwetted length of the elongated probe located above the level of the liquid. A thermal conductor or an electrical heater is provided for maintaining a temperature difference between the proximal end of the elongated probe and the liquid so that at an intermediate location of the elongated probe, located above the level of the liquid, the temperature will be dependent upon the unwetted length of the elongated probe. A thermocouple or the like can be provided for generating a signal referable to the temperature at the intermediate location and the level of the liquid can thereby be correlated with such signal.

Abstract: A cryogen delivery apparatus for delivering cryogen in a saturated state includes a vessel to contain the cryogen in liquid and vapor phases. The vessel has a headspace region and a heat exchanger located within the headspace region for indirectly exchanging heat between the vapor located within the headspace region and a liquid stream composed of the liquid phase of the cryogen. In case the cryogen is introduced into the vessel as a subcooled liquid, the vapor will condense into the liquid phase and the subcooled liquid will be converted into a saturated liquid. The saturated liquid will then be discharged from a liquid outlet connected to the heat exchanger. In the event the liquid enters the vessel as two-phase flow, the vessel will act as a phase separator. A branched supply line is provided having a liquid inlet branch connected to a bottom liquid inlet of the vessel so that a supply stream composed of the cryogen flows into the vessel.

Abstract: An apparatus for storing a multi-component cryogenic liquid in which headspace vapor in a storage tank is condensed in an external condensation tank through indirect heat exchange with liquid being vented from the storage tank. The resulting condensate can then be re-introduced into the storage tank through a pressure building circuit applied to the external condensation tank. In such manner, the pressure within the storage tank is regulated and the composition of the liquid stored within the storage tank is held with some degree of consistency. The use of an external condensation tank allows prior art cryogenic storage tanks and dewars to be retrofitted to store a multi-component cryogenic liquids.

Abstract: A process and system for removing condensable vapors contained within the gas stream in accordance with the process and system, condensable vapors contained within the gas stream are condensed within one or more condensers through indirect heat exchange of the gas stream with a refrigerant stream. This produces a refrigerated gas stream and a heated refrigerant gas stream. Further heat is exchanged from at least part of the heated refrigerant stream to the refrigerated gas stream and in economizing heat exchanger to form a cooled refrigerant stream from the heated refrigerant stream. The refrigeration stream is produced by combining a cryogenic stream with the at least part of the cooled refrigerant stream in a mixing chamber of an ejector or analogous equipment.

Abstract: A cryogenic heat exchange system and freer dryer incorporating the same. The cryogenic heat exchange system has a heat exchanger provided with at least one pass for receiving a cryogenic heat exchange fluid. A reversing circuit is provided to reverse the flow direction of the cryogenic heat transfer fluid in the at least one pass to help prevent asymmetric ice buildup on the heat exchanger. Additionally, a portion of the spent cryogenic heat transfer fluid after having passed through the at least one pass is recirculated. During the recirculation, the spent cryogenic heat transfer fluid is mixed with incoming cryogen to produce the cryogenic heat transfer fluid. Such cryogenic heat transfer fluid after creation is then introduced into the flow reversing circuit and the one or more passes of the heat exchanger. A remaining portion of the cryogenic heat transfer fluid is vented. The recirculation raises the temperature of the heat transfer in the heat exchanger to also promote uniform ice buildup.

Abstract: A refrigeration device in which a heat load is refrigerated within a refrigeration chamber. Refrigerant is supplied, preferably, from a supply of turboexpanded air employing a compressor to compress the air and a turboexpander to expand the compressed air to a low temperature. A venturi-like device such as an ejector circulates the refrigerant within a circulation path within the refrigeration chamber so that heat is transferred from the heat load to the refrigerant. An incoming mass flow rate of the refrigerant is delivered to a high pressure inlet of the venturi-like device and a recirculation mass flow rate of the refrigerant is received within the low pressure inlet from the circulation path after the refrigerant has heat transferred thereto. A high pressure outlet discharges a mixture of the refrigerant that comprises the incoming and recirculation mass flow rates to the circulation path and prior to the heat load.

Abstract: A method and apparatus for subcooling a liquid composed of a volatile fluid, for instance, a saturated liquid cryogen, in which two chambers are filled with the fluid and are each initially pressurized after filling so that the fluid is converted to a subcooled liquid. The pressurization of the two chambers is maintained as the subcooled liquid is delivered from each of the two chambers. The filling and the delivery of the two chambers is effected in accordance with a cycle in which one chamber is filled and initially pressurized just prior to the completion of the delivery from the other chamber to allow the continual delivery of the subcooled liquid.

Abstract: A freezer having a freezing compartment and a porous conveyor belt for conveying articles through the freezing compartment. A vaporizer is provided to vaporize a stream of liquid cryogen. Vaporized cryogen is directed against the belt as a plurality of jets to blow accumulated ice off the belt. The vaporizer is located within the freezing compartment so that the cooling potential of the cryogen is not wasted and the vaporizer can serve as a preferential condensation site for the moisture.

Abstract: A method and apparatus for cooling a heat load in which a pressure vessel is provided to contain a cryogen as a saturated liquid and saturated vapor separated by liquid-vapor interface. The pressure vessel has an inlet adapted to receive a subcooled liquid cryogen and thereby convert it to a saturated liquid through contact with the saturated vapor. A heated overflow tube projects into the pressure vessel and is level, at one end, with the liquid-vapor interface so that any increase in the saturated liquid overflows into overflow tube and is vaporized to form the saturated vapor. The heat transfer and the reintroduction of the vaporized liquid can be effected through forced circulation provided by an ejector. Preferably the pressure vessel is provided with two outlets for discharging the saturated cryogen as saturated liquid or vapor.

Abstract: A liquid cryogen is supplied, preferably by means of a reservoir, to a dispensing tube so that the liquid cryogen tends to flow from the dispensing tube. A heating coil wrapped around the dispensing tube heats the dispensing tube so that the liquid cryogen undergoes nucleate boiling within the dispensing tube to form a vapor block, and thereby at least impede the liquid cryogen from flowing from the dispensing tube. Flow is reestablished within the dispensing tube by terminating the heating of the dispensing tube, e.g. by turning off electrical power supplied to the heating coil. The heating of the dispensing tube can be sufficient to stop the flow of liquid cryogen. Additionally, the dispensing tube can be cyclically heated by a timing circuit connected to the heating coil. Such cyclical heating is used to throttle the flow of the liquid cryogen from the dispensing tube.

Abstract: An article is formed in a mold by blowing a hot plastic material with a blowing gas. A cooling fluid is introduced into the article to cool the article and allow its removal from the mold. A warmed gaseous form of a cryogen is added to a pressurized liquid form of the cryogen to form the cooling fluid by introducing the pressurized form of the cryogen into a jet pump and drawing the warmed gaseous form of the cryogen in the pressurized liquid form of the cryogen. The resultant cooling fluid circulates through the article by being introduced into the article and discharged from the article by two or more blow pins. Part of the discharged cooling fluid is then recovered in a storage tank. The cooling fluid, which after cooling the article is composed of the warmed gaseous form of the cryogen, is then drawn from the storage tank into the jet pump during formation of the cooling fluid. Additionally, the blowing gas can comprise cooling fluid formed in the manner outlined above.

Abstract: The present invention provides a food processing system and method for refrigerating articles of food. The food processing system includes at least two cooling stages formed by a cryogenic freezer and a hydrocooler. The cryogenic freezer receives the articles of food and transfers heat from the articles of food to the cryogen so that the articles of food are refrigerated. After the transfer of heat from the articles of food to the cryogen, the cryogen boils off to form cryogenic vapor. The hydrocooler receives the articles of food prior to the cryogenic freezer and transfers heat from the articles of food to supplied cooling water. Such heat transfer reduces the quantity of cryogen required to refrigerate the articles of food. Additionally, an eductor is connected to a pump and to vent line from the cryogenic freezer.

Abstract: Apparatus and method for cooling an extruded blown film in which the interior surface of the thin film bubble is contacted with a gas which does not contain water vapor to thereby cool the extruded film. The apparatus and method may employ an enclosed circulation system to provide for the reuse of the gas through cooling with a liquid coolant such as liquid cryogen.

Abstract: The present invention provides a level detector to sense whether the level of a liquid having a nonambient temperature such as a cryogenic liquid has reached a predetermined point. A stainless steel type T thermocouple probe is provided for generating a temperature signal referrable to absolute temperature. A high thermal conductivity the type T thermocouple probe is adapted to be mounted so that it submerges in the liquid when the level of the liquid has reached the predetermined point tube is, at one end, in good thermal contact with a thermocouple contained within distal end of the thermocouple probe and, at the other end, is exposed to ambient conditions. The high thermal conductivity tube acts to conduct heat between the ambient and the thermocouple.

Abstract: The present invention relates to a cryogen delivery apparatus and method for delivering a flowing cryogen with a regulated cooling potential. The apparatus includes a pressure vessel for receiving a liquid form of the cryogen. A liquid-vapor interface is maintained within the pressure vessel so that a gaseous form of the cryogen having a low cooling potential is situated above the liquid-vapor interface and a liquid form of the cryogen having a high cooling potential is situated below the liquid-vapor interface. An outlet conduit is provided for delivering the gas and liquid forms of the cryogen from the pressure vessel. The conduit has a moveable end section located within the pressure vessel. When the moveable end section is oscillated above and below the level of a liquid-vapor interface, a two-phase flow of cryogen is delivered comprising the pure gaseous and liquid forms of the cryogen.

Abstract: The present invention relates to an apparatus for delivery of pure gaseous and liquid forms of cryogen. The apparatus includes a pressure vessel for receiving a liquid form of the cryogen. A liquid-vapor interface is maintained within the pressure vessel by a liquid level detector and a cut-off valve connected to the level detector to vent the gaseous form of the cryogen to the atmosphere when the liquid form falls below a predetermined level. A heated overflow tube projects into the pressure vessel and is positioned at the predetermined level of the liquid. When the liquid rises above the predetermined level, it flowws into the overflow tube and is heated to vapor to add to the gaseous form of the cryogen within the pressure vessel. An outlet conduit is provided for delivering the gas and liquid forms of the cryogen from the pressure vessel. The conduit has a moveable end section located within the pressure vessel.