Abstract: To improve cooling efficiency of a pulse tube refrigerator, it is found that creating two conditions in the refrigerator, particularly in a regenerator is effective. In a first condition, working fluid in the regenerator should be compressed or expanded without having any displacement thereof, while it should be displaced without compression or expansion in a second condition. In order to realize this idea, a fluid displacement control valve assembly including two relief valves is disposed between a pulse tube and a buffer tank. Each of the relief valves is a normally closed one-way valve, and the valves open in opposite directions to one another when a pressure difference between the pulse tube and the buffer tank reaches a predetermined value, thus allowing the working fluid to be displaced after its compression from the pulse tube to the buffer tank and after its expansion from the buffer tank to the pulse tube.

Abstract: A control system is provided for a cryogenic refrigeration system having an evaporator-heater coil, an electronically controlled valve for regulating the amount of cryogenic gas to the coil, and a vapor motor powered by the cryogenic gas that drives both an alternator for recharging the system battery, and a fan for generating an air flow through the coil and into a conditioned space. The control system includes a temperature sensor for generating an electrical signal indicative of the temperature of the conditioned space, and a microprocessor that is electrically connected to the temperature sensor, the alternator, and the electronically controlled valve for modulating the flow of cryogenic gas through the evaporator-heater coil in said vapor motor to achieve a selected set point temperature in the conditioned space, and to maintain a sufficient alternator current to effectively recharge the system battery.

Abstract: A cryogenic refrigerator which is capable of preventing a deterioration in refrigerating performance and which has high efficiency includes: a first compressor; a first expander having at least one accumulator using an accumulating material comprising a rare earth alloy or compound which has a large specific weight at 10K or below or an accumulating material comprising helium; a sub-expansion space which effects further expansion of a working fluid introduced thereto from an expansion space of the first expander; and a second compressor which compresses the working fluid returning from the sub-expansion space.

Abstract: A magnetic resonance imaging apparatus generates a radiofrequency magnetic field to excite magnetization spins of a subject placed in a static magnetic field, and which receives magnetic resonance signals generated from the excited magnetization spins so as to generate an image of the subject based on the received magnetic resonance signals. A superconducting coil carries out at least one of generation of the radiofrequency magnetic field and a reception of the magnetic resonance signals. A cryostat has a refrigerant container therein. The refrigerant container contains refrigerant and the superconducting coil. A flow space is formed between the refrigerant container and a surface of the cryostat. Fluid having appropriate temperature and amount of supply is made to flow to the flow space, thereby temperature of a surface of the cryostat can be maintained in a predetermined range. The subject is directly placed on the surface of the cryostat.

Abstract: A fluid mixture is separated by distillation in a two column system in which the feed is prefractionated in a first column having at least one separation stage above the feed and the prefractionator bottoms provides feed to a second column operating at a lower pressure. Cooling for condensing the overhead vapor of the first column is provided by indirect heat exchange with a flashed portion of the feed or with an intermediate fluid obtained from the second column. The two-column system is readily combined with a high pressure column in a three-column distillation system for separating air which is particularly useful for integration with a gasification combined cycle combustion turbine system. Optionally, three nitrogen products can be produced at three different pressures.

Abstract: A first stream of argon-enriched oxygen is separated in a first rectification column to form oxygen vapour further enriched in argon and a second stream of argon-enriched oxygen is introduced into a second rectification column operating at a lower pressure than the first rectification column. A vapour flow upwardly through the second rectification column is created by reboiling in a reboiler-condenser liquid separated therein. The further-enriched oxygen vapour is condensed in the reboiler-condenser by indirect heat exchange with said separated liquid. One stream of the condensed further-enriched oxygen vapour is employed as reflux in the first rectification column. A third argon-enriched oxygen stream is introduced in liquid state into an intermediate mass exchange region of the second rectification column. An argon product is separated in the second rectification column.

Abstract: A Group I gas cryopumping system includes a compressor throttle cycle refrigerator using mixed refrigerants. Cold refrigerant flows through a cryopumping surface located in a vacuum chamber, whereon vapor freezes. The refrigerant then passes through a heat exchanger in cross flow with refrigerant from the compressor. Refrigerant flow entering and leaving the heat exchanger is in uninsulated lines at substantially room temperature. All exposed cold lines are eliminated. The throttle device and cold cryopumping surface are an integral unit that connects directly to the flow paths of the heat exchanger without intermediate lines. The compressor/aftercooler unit may be located at any convenient distance from the heat exchanger and cryopumping surface, and the heat exchanger is located immediately adjacent to the pumping surface in a separate housing outside the vacuum chamber. The heat exchanger housing may share or be isolated from the vacuum of the vacuum chamber.

Abstract: A method and apparatus for preparing high purity hydrogen bromide, wherein a starting hydrogen bromide which contains impurities having low boiling points is supplied to an intermediate space. While the gas phase of the starting hydrogen bromide is allowed to ascend through an upper rectifying section, it is brought into contact with a first reflux solution flowing in the reverse direction. The uncondensed gas stored in an upper space is cooled and partly condensed. The condensed liquid is allowed to flow down through an upper rectifying section as the first reflux solution. The liquid-phase of the starting hydrogen bromide is mixed with the first reflux solution in the intermediate space and serves as a second reflux solution. The liquid stored in a lower space is heated and partly evaporated. The liquid stored in the lower space is supplied outside as high purity hydrogen bromide. The uncondensed gas stored in the upper space is discharged outside.

Abstract: A method of separating from gaseous media, such as air or technical gases, organic vapors by substantially isothermally raising the pressure of the media and subjecting them to cooling in a cold scrubber receiving its operating low temperature from circulating first and second flows of refrigerants of moderate and significant refrigeration parameters and provided by resulting condensates.

Abstract: The present invention relates to a method and system for storing cold fluid. The system includes a main tank and an auxiliary tank that are in fluid communication, and the auxiliary tank receives vapor and expanding fluid as the cold fluid in the main tank warms thereby avoiding overpressurization of the system.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce high pressure nitrogen of various purity, varying from moderately high purity (99.9% nitrogen) to ultra-high purity (less than 1 part per billion of oxygen). The process is particularly suited for cases where the high pressure nitrogen is needed directly from the distillation column system to avoid contamination concerns associated with compressing nitrogen that is produced at lower pressures. The process uses a high pressure column, which operates at a pressure to directly produce the nitrogen at the desired high pressure, and one or more lower pressure columns which produces a portion of the nitrogen product at a lower pressure. At least a portion of the lower pressure nitrogen is compressed and fed to the high pressure column at a location which is below the removal location of the high pressure nitrogen.

Abstract: A process and system for producing an argon-enriched stream comprising a multiple column air separation system, a first crude argon column, and a second crude argon column is provided. The improved process involves removing a vapor stream from the upper portion of the first argon column; reducing the pressure of the vapor in a pressure reducing device; and then flowing the reduced pressure vapor to a second argon column which operates at a lower operating pressure relative to the first argon column.

Abstract: A double column cryogenic rectification system for producing low purity oxygen and high purity nitrogen, preferably at elevated pressure, wherein nitrogen-rich vapor from the higher pressure column is turboexpanded and condensed against lower pressure column intermediate liquid prior to being passed into the lower pressure column.

Abstract: A self-contained liquefied gas supply system has a tank for storing a liquefied gas, a primary pump for delivering the liquefied gas from the tank, a secondary pump for pressurizing the liquefied gas delivered from the primary pump, a vaporizer for vaporizing the liquefied gas discharged from the secondary pump into a vaporized gas, an expander for actuating the secondary pump with the vaporized gas produced by the vaporizer, and a back-pressure line connected to an outlet of the expander. A bypass pipe is connected between the primary pump and the vaporizer in bypassing relation to the secondary pump for supplying the liquefied gas from the primary pump to the vaporizer. A joint line is connected between the back-pressure line and a substantially atmospheric pressure line, the joint line having a first flow regulating valve for regulating a rate of flow of a gas from the back-pressure line to the substantially atmospheric pressure line.

Abstract: A cryogenic method and apparatus using a liquefier and a two stage distillation column capable of operating in two modes, namely a first mode of operation during which only liquid nitrogen is produced and a second mode of operation during which liquid nitrogen and liquid oxygen are produced. By adjusting the time of operation in each mode, any ratio of liquid nitrogen to liquid oxygen greater than the ratio achieved during the second mode of operation can be achieved. In the first mode of operation, a condenser is used to condense the lower pressure stage gaseous nitrogen into lower pressure stage nitrogen condensate. To condense the lower pressure stage gaseous nitrogen, either at least a portion of the crude oxygen liquid from the higher pressure stage, at least a portion of the oxygen-enriched liquid from the lower pressure stage, at least a portion of the liquefied air, or mixtures thereof, are introduced to the condenser.

Abstract: A method for the recovery of volatile organic components (VOC) released when loading liquid hydrocarbons into a storage or cargo tank, is described. The VOCs issuing from the tank are compressed, and injected into a sidestream taken from the main hydrocarbon stream, which is cooled and used as the absorbing medium, and is conducted to a VOC recovery unit comprising at least a bi-phase rotary separator turbine (BRST). In the BRST the VOC-containing gas is substantially separated into a VOC component and inert gas. The inert gas is vented to the atmosphere. The VOC component or VOC-enriched liquid stream is then returned to the main cargo stream or a cargo tank. Any methane contained in the volatile gases issuing from the cargo tank, instead of being vented to the atmosphere, is recovered or a catalytic process is used to convert methane to carbon dioxide and water for discharge to the atmosphere. The system is particularly intended for the offshore loading of oil into tankers.

Abstract: In accordance with the present invention, methods and systems are provided which afford solutions to the problems of gas distribution of ultra-high purity ESGs at high gas flow rates. A first aspect of the invention is a system comprising a compressed liquefied gas container; an internal heat exchanger within the compressed liquefied gas container; a gas supply conduit which takes feed from the container and delivers the ESG to a process; and an external heat exchanger positioned effectively near the conduit downstream of the container but upstream of the process.

Abstract: The present invention is a set of improvements in deethanizing and depropanizing fractionation steps in NGL processing. The several embodiments of the present invention apply component distribution to multiple columns, interreboiling, intercondensing, thermal coupling and "thermo-mechanical" coupling to the commonly practiced deethanizer/depropanizer fractionation sequence of NGL processing.

Abstract: A process and apparatus are provided for recovering volatile vapors from an air-volatile mixture. The process includes cooling the mixture to condense volatile liquid vapors and moisture, collecting the condensed volatile liquid vapors and moisture, circulating the cooled and dehumidified mixture through a bed of adsorbent, and desorbing and recovering the volatile liquids from the bed. The apparatus includes a refrigeration unit (24), a cooler (20) for cooling the mixture, two reaction vessels (36, 36') each including a bed of adsorbent (38, 38'), a pump (50), an absorber tower (72) and a valve and conduit system for circulating the mixture through the various components of the apparatus. Heat may be recovered from the refrigerant and used to heat the bed during desorption.

Abstract: In a heat exchange scheme associated with a gas purification column in an LNG recovery process, in which heat exchange is desired between fluids of such widely different temperatures that thermal shock could result in damage to heat exchanger apparatus, a control scheme compensates for the effect of excessive temperature differential. The desired compensation is achieved by manipulating flow in a heat exchanger bypass conduit for the warm fluid to maintain a desired temperature ratio between the colder fluid entering the heat exchanger and the warmer fluid exiting the exchanger. Additionally, start-up controls for the column include temporarily selecting temperature of a cold stream to automatically control opening of a valve to initiate flow of the warm stream.