Abstract: A cryogenic nitrogen production plant wherein all the heat transfer steps, and preferably all the heat transfer and separation steps, are carried out in a brazement which receives feed air and from which is recovered product nitrogen.

Abstract: The process and the apparatus serve for evaporating liquid oxygen. In the normal operation liquid oxygen is introduced into a main evaporator (3) and there partially evaporated, a first flushing stream (5) is removed in the liquid state from the main evaporator (3), the first flushing stream (5) is partially evaporated in an auxiliary evaporator (6) and a second flushing stream (7) is taken off in the liquid state from the auxiliary evaporator (6). The normal operation is interrupted by a heating operation in which no liquid (5) is passed from the main evaporator (3) into the auxiliary evaporator (6) and the auxiliary evaporator (6) is brought to a temperature which is markedly higher than its temperature in the normal operation.

Abstract: The invention relates to a method for extracting xenon and eventually also krypton from a liquid oxygen (LOX) charge, as it accrues in a cryogenic air separation system (LZA) during a rectification of the air, mostly as a bottom product of a low-pressure, column, namely with xenon (Xe), krypton (Kr) and hydrocarbons (CxHy) in a small concentration and approximately 99 mol % oxygen (O2). According to the inventive method, the LOX charge is fed to a first column, the oxygen of the LOX charge is extensively removed by stripping with an inert gas, and is extracted in the top gas, whereas the inert gas is withdrawn in the form of a liquid from the bottom of the first column with little O2 and nearly the total mass of CxHy, Kr, Xe. According to the invention, the liquid discharge is fed to a second column without prior catalytic and/or adsorptive removal of CxHy. A Kr fraction is extracted as top gas of the second column, and an Xe fraction is withdrawn from the bottom of the second column.

Abstract: A thermodynamic power and cryogenic refrigeration system using a first and second (binary) working fluid has a low-temperature closed bottoming cycle and an open or closed topping cycle. In the bottoming cycle a mixture of a first gas such as helium or hydrogen and a low temperature liquid such as liquefied nitrogen is compressed in a polytropic process and then the liquid content is separated. The separated first gas is heated using rejected heat from a second gas expanded in the topping cycle or ambient air and then the heated first gas is adiabatically expanded and supercooled while performing useful work and thereafter is fed to the compressor and mixed with the separated liquid to serve as a coolant and facilitate rejection of polytropic heat and to supplement the cool gas/liquid mixture providing polytropic compression of the first gas and thus completes the bottoming cycle. The bottoming cycle functions to cool the second gas and liquefy it in the topping cycle.

Abstract: Dephlegmator system without headers, collectors, or distributors at the bottom end of feed circuits in plate and fin exchangers operating in condensing or rectifying service. Each dephlegmator is installed within a pressure vessel, thereby eliminating the need for headers, collectors, or distributors at the bottom end of the feed circuits. In an alternative embodiment of the invention, upper and lower segments of the pressure vessel are isolated by a mid-vessel seal between the vessel and dephlegmator walls, and headers or collectors are not required at the upper and lower ends of the feed circuits.

Abstract: Method of producing liquefied natural gas (LNG) whereby refrigeration for cooling and liquefaction is provided by a mixed refrigerant system precooled by another refrigeration system. At least one liquid stream is derived from the partial condensation and separation of the mixed refrigerant at a temperature higher than the lowest temperature provided by the precooling system when the mixed refrigerant is condensed at a final highest pressure. When the mixed refrigerant is condensed at a pressure lower than the final highest pressure, condensation is effected at a temperatures equal or higher than the lowest temperature provided by the precooling system. The mixed refrigerant liquid is used to provide refrigeration at a temperature lower than that provided by the precooling system.

Abstract: Air is separated in a triple column comprising a high pressure column, an intermediate pressure column and a low pressure column, the intermediate pressure column being fed by oxygen enriched liquid from the high pressure column. The low pressure column feeds an argon column with argon enriched liquid and operates at a higher pressure than the argon column. Heat is supplied to the bottom of the argon column by sending gas to a bottom reboiler. This gas is preferably rich in nitrogen and may come from the top of the low pressure column.

Abstract: A method of gas liquefaction wherein the refrigeration to cool and liquefy an essentially water-free feed gas is provided by a single recirculating mixed refrigerant cycle in which refrigeration is provided by the vaporization of two mixed refrigerant streams of different compositions at a lower and higher pressure levels respectively. A lower pressure level vaporizing refrigerant cools the feed gas stream in a first cooling zone and a higher pressure level vaporizing refrigerant further cools and condenses the cooled gas in a second cooling zone to provide the final liquid product. The lower pressure level vaporizing refrigerant is provided by one or more liquids obtained by ambient cooling of compressed mixed refrigerant vapor.

Abstract: This invention is directed to a method of ice seeding a biological samples, such as cells, harvested tissues, and cellular biological constructs such as culture tissue equivalents. The method initiates the formation of ice that is controllable to allow for maximal viability of the sample to be cryopreserved after it has been subsequently thawed.

Abstract: A heat exchanger is disclosed having a first chamber, a second chamber positioned inside the first chamber, and a third chamber positioned inside the second chamber. The first, second, and third chambers are in coaxial alignment. A first portion of a first helical tube is positioned inside the second chamber and a second portion of the first helical tube is positioned inside the third chamber and a second helical tube is positioned inside the first chamber. The heat exchanger heats a cryogenic liquid to a gas phase using at least three different heat transfer fluids in one contained unit without mixing any of the fluids in the exchanger.

Abstract: The invention relates to a method and a device for separating a gas component in a gas mixture by freezing. The gas component to be separated has the lower vapor pressure when compared with the other gas components in the gas mixture. A working temperature is chosen at which the gas components to be separated freezes out almost completely. The partial pressure of the other gas components at working temperature is kept lower than the vapor temperature of the other gas components at working temperature. Once the components to be separated have been frozen out, the other gases are evacuated. The device comprises at least two cooling tanks. Means are provided to alternately feed the gas mixture to the cooling tanks so that a predetermined partial pressure arises in each tank.

Abstract: Air is distilled in a single column installed on a boat, and from here an oxygen-enriched liquid flow is drawn off. This flow is pressurized by a pump and vaporized by heat exchange with air or nitrogen. The oxygen is used for the partial oxidation of a flow contained hydrocarbons, for example natural gas.

Abstract: Single-use heat transfer container has an insulated product chamber containing a reaction vessel holding two separate reactants. The product chamber is partially defined by the reaction vessel which is integrally sealed thereto near a lower end of the container. The reaction vessel has a flexible bottom that is responsive to external pressure. An activation pin on the interior of the bottom is capable of piercing a barrier inside the reagent vessel when the container bottom is depressed. The resulting mixing of the separately stable reactants in the vessel initiates the desired heat transfer reaction. The container may have a cover including storage compartments for user dispensable additives. The method of making the inventive container is disclosed.

Abstract: This device comprises a closed heating chamber (36) extending through the wall (3, 4, 5) of the tank and connected to this wall, a feed pipe (22) suitable for feeding the heating chamber (36) with a heating fluid having a temperature above the temperature of the cryogenic fluid, and an exhaust pipe (23) intended for discharging the heating fluid, each of the pipes intended for discharging the heating fluid, each of the pipes (22, 23) passing through an outer wall (20) of the heating chamber (36). The device is particularly useful in the delivery of ultrapure helium.

Abstract: A system wherein flashoff losses from cryogenic liquid tankage are reduced wherein fluid from the tankage is condensed and subcooled against refrigeration bearing refrigerant fluid generated by an exogenous refrigeration system.

Abstract: A device for crystallization of a component from a liquid mixture comprising a chamber, a first conduit connected to said chamber for supplying said mixture, a second conduit connected to and in connection with said chamber for introducing cold gas, a third conduit for withdrawing warmed gas from said crystallizer, a turbo-expander for cooling gas withdrawn from said chamber, and a fourth conduit Icading from the turbo-expander to said chamber. The device has particular application for the crystallization of paraxylene.

Abstract: A cooling tunnel system that includes a conveyor for carrying objects through a tunnel chamber. The conveyor enables a cooling fluid to pass therethrouqh and about the objects. A plurality of slot means feeds the cooling fluid to the conveyor means. Each slot means includes at least one aperture for enabling vapor flow onto and about the objects. A plenum adjacent the plurality of slot means distributes the cooling fluid. And at least one fan in the tunnel chamber causes a flow of the cooling fluid into the plenum and through the slot means with sufficient velocity to impinge upon and cool the objects and to recirculate the cooling fluid within the tunnel chamber.

Abstract: Fire prevention and suppression system is provided for computer cabinets and fire-hazardous containers. The equipment of the system provides low-oxygen environments at standard atmospheric pressure. The system employs an oxygen-extraction apparatus that supplies oxygen-depleted air inside an enclosed area communicating with the device. A fire-extinguishing composition is provided for continuous use in computer cabinets and fire-hazardous containers, consisting of oxygen-depleted air having oxygen content below 12%.

Abstract: In the liquefaction of a hydrocarbon by indirect heat exchange with the refrigerant mixture of a refrigerant mixture cycle, the refrigerant mixture being compressed in multiple stages, the compressed refrigerant mixture (23) is at least partially condensed (E4) downstream of the penultimate compressor stage and is fractionated (D4) into a higher-boiling liquid fraction (26) and a lower-boiling gas fraction (24). The lower-boiling gas fraction (24) is compressed to the final pressure, partially condensed (E5) and fractionated (D5) into a lower-boiling gas fraction (10) and a higher-boiling liquid fraction (27). The higher-boiling liquid fraction (27) is added to the partially condensed refrigerant mixture stream (23), and the gas fraction (10) forms the lower-boiling refrigerant mixture fraction and the liquid fraction (26) forms the higher boiling refrigerant mixture fraction of the refrigerant mixture cycle.

Abstract: An objective in a natural gas liquids (NGL) plant is that of achieving and maintaining maximum productivity. If this plant is equipped with a turboexpander that drives a gas compressor (recompressor), maximum turboexpander productivity provides maximum plant productivity attained by maximum compressor power. This is accomplished by manipulating the compressor operating point location (by adjusting the opening of the antisurge valve) and by controlling rotational speed. The subjects of the proposed invention are the method and apparatus (comprising a turboexpander/recompressor rotational speed controller and a recompressor antisurge controller) providing maximum turboexpander/recompressor rotational speed and recompressor operating point location (corresponding to maximum power) by opening the turboexpander's adjustable nozzles and the recompressor antisurge valve.