Abstract: A thermodynamic engine comprises first and second heat exchange members and a solid state thermodynamic member therebetween. At least one of the heat exchange members is formed by use of micromechanical machining.

Abstract: Process and installation for the compression and expansion of at least one gaseous stream, in which a first stream of a gaseous mixture is compressed in a compressor (5) having at least one compression stage (5A, 5B, 5C); a second stream of a gaseous mixture is supercharged in a supercharger (7); a third stream of a gaseous mixture is expanded in an expansion engine (9); at least a portion of the energy generated by the expansion engine is recovered with the supercharger (7) and at least a portion of the second supercharged stream is sent upstream of one stage (5B) of the compressor. The first and second streams are compressed in at least one stage (5A) of the compressor before sending the second stream to the supercharger. The second stream comes from upstream of one stage of the compressor and at least a portion of the supercharged second stream is returned downstream of this stage.

Abstract: A system for delivering a controlled stream of purified liquid cryogen from an outlet. The system includes a cryogen delivery flow path that is made up of a delivery conduit connecting a source of liquid cryogen to the outlet. A cryogen purifier positioned in a section of the conduit, is capable of purifying (sterilizing) liquid cryogen flowing therethrough, and a section of the delivery conduit downstream of the cryogen purifier is clean (sterile). The system also includes a cleansing flow path for cleansing (sterilizing) the cryogen purifier and the clean delivery conduit section. The cleansing flow path includes a cleansing conduit connecting a source of cleansing (sterilizing) medium to the delivery conduit and the cryogen purifier. The cryogen purifier and clean delivery conduit section are isolated from the cryogen source during conduit cleansing, and cleansing is accomplished without subjecting the cryogen source to the cleansing medium.

Abstract: This invention relates to a process and apparatus for producing high purity product grade argon from an argon-containing stream using a cryogenic argon column in combination with a solid electrolyte ionic or mixed conductor membrane.

Abstract: Rapid cooling or freezing of foodstuffs, perishables or blood products is accomplished by using a thin film membrane to totally envelope the foodstuffs or blood product only during the heat extraction period. This thin film encapsulation system closes around the item and is held tightly to the item by atmospheric and/or hydrostatic pressure. Once the item is encapsulated, low temperature heat transfer fluids are then circulated on the exterior surface of the membrane, thus extracting the heat within the item through the thickness of the membrane. Upon completion of the necessary chilling or freezing, the atmospheric and/or hydrostatic pressure is withdrawn and the chilled or frozen item is extracted.

Abstract: Method and apparatus for using a centrifugal compressor during the exhaust portion of the cycle in a pressure vessel used to separate components from a gaseous mixture by pressure swing or vacuum swing adsorption. Energy input to the motor of an electrically driven motor-compressor is minimized at a time when the exhaust portion of the cycle is initiated allowing rotation of the compressor wheel to decelerate by contact with the absorbed gaseous components until the speed of rotation of the compressor wheel matches the efficient compression ratio for the compressor and then reenergizing the motor to increase the speed of rotation of the compressor wheel according to the best efficiency curve for said compressor until a full outlet to inlet pressure ratio across said compressor is achieved.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is cooled to partially condense it, then separated to provide a first vapor stream and a first condensed stream. The first vapor stream is divided into first and second streams, then the first stream is combined with the first condensed stream. The combined stream is cooled and expanded to an intermediate pressure to partially condense it, then separated to provide a second vapor stream and a second condensed stream. The second vapor stream is cooled at the intermediate pressure to condense substantially all of it and is thereafter expanded to the fractionation tower pressure and supplied to the fractionation tower at a top feed position. The second condensed stream is subcooled at the intermediate pressure, expanded to the tower pressure, and is supplied to the column at a first mid-column feed position.

Abstract: A clathrate freeze desalination system and method in which a clathrate forming agent is injected through a submerged pipeline to a predetermined ocean depth at which the surrounding ocean temperature is less than the clathrate forming temperature. The agent combines with the salt water to form a slurry of clathrate ice crystals and brine. The pipeline is concentric and coaxial with a surrounding outer pipeline in which the slurry is formed. The slurry is pumped back to the surface through the outer pipeline and the ice crystals are washed to remove brine. The washed crystals are then melted, and the resultant water is separated from the clathrate forming agent, which may be discarded or recycled for re-injection through the inner pipeline. The melting of the clathrate ice as well as the cold water and air circulating in the desalination plant can be utilized as a source of air conditioning for local buildings and facilities.

Abstract: A tunnel freezing system employs multiple high velocity refrigerated air impingement jets to quick freeze food products such as hamburger patties and fish or chicken filets. Ultra high molecular weight polyethylene blocks are provided with a multiplicity of internal jet nozzles. These blocks are located in air ducts located above and below a conveyor belt so that the topsides and bottomsides of food products are impinged with the high velocity jets of refrigerated air so as to break up the boundary layer around the products to effect a much higher rate of heat transfer. A dual conveyor line employs direct drive centrifugal fans to deliver high pressure refrigerated air to the air ducts. The air ducts are spaced apart so that return air can freely return to be re-refrigerated after impinging on the food products.

Abstract: A hybrid thermoelectric/Joule-Thomson cryostat with a finite cryogenic gas supply is configured to greatly increase the cold operating time of a infrared detector array. A Joule-Thomson cryostat is located within a dewar vessel along with the infrared detector array to be cooled. Cryogenic gas from a cryogenic gas source is pre-cooled by a thermoelectric cooler at a location remote from the dewar vessel. Final cooling of the cryogenic gas is then performed by a demand flow Joule-Thomson cooler which has the ability to provide the low temperatures necessary for operation of an infrared detector. The operating period of the cryogenic gas supply and Joule-Thomson cryostat are increased by the cryogenic assistance of the thermoelectric cooler.

Abstract: A demand-flow Joule-Thomson cryostat 10' adapted for use with multiple coolants uses a replaceable coolant supply reservoir 21' to fill a coolant flow control bellows 17' within the cryostat with the same coolant used to provide refrigeration to the thermal load 15'. Upon termination of the cooling cycle, the bellows 17' is drained of coolant and thus prepared for operation from a different coolant supply 21' that may contain a different cryogen.

Abstract: An air separating unit which can jointly produce high purity nitrogen gas and compressed dry air of high quality freed of hydrocarbons such as methane and ethane. The air separating unit is constructed such that compressed dry air freed of hydrogen, carbon monoxide, carbon dioxide and moisture is cooled down near to its liquefying point and introduced into a rectification column (30) and nitrogen gas separated by rectification from the compressed dry air in this rectification column (30) is taken out as a product. The rectifying portion in the rectification column (30) is divided into a lower rectifying portion (34) and an upper rectifying portion (36), and in this lower rectifying portion (34), hydrocarbons such as methane are mainly removed from the compressed dry air, and the compressed dry air which has passed through the lower rectifying portion (34) is taken out as a product.

Abstract: A device for maintaining a vacuum in a thermally insulating jacket is described. The device comprises a container formed of a gas-tight material, preferably aluminum, which has an opening to the atmosphere. Inside the container is a first pellet comprising a powder of a Ba--Li alloy getter material. Arranged above, and completely covering, the first pellet is a second pellet comprising a powder of a drying material, optionally including the oxide of a noble metal and a material to prevent contraction of the drier. A process for manufacturing such a device is also described in which the first pellet is obtained by compression of its constituent powders at a pressure between about 30 bar and 1000 bar.

Abstract: An improved cryogenic cooler 100 includes a flange 106 with an elongated pressure vessel 120 extending therefrom. The pressure vessel 120 is connected to the flange 106 at a proximal end thereof. The pressure vessel 120 is adapted to cool a surface in the proximity of the distal end thereof. Vibration isolation is provided at both proximal and distal ends of the elongated pressure vessel. A coupler 126 serves to maintain a gap between the distal end of the pressure vessel 120 and the surface at cryogenic temperatures. In a specific embodiment, the coupler 234 has a coefficient of thermal expansion which is less than the coefficient of thermal expansion of an end cap 224 on the pressure vessel. The coefficients of expansion are chosen to provide a tight slip fit between the cooler and the coupler at ambient temperatures and a very small continuous air gap at cryogenic temperatures. Another novel feature is the provision of an energy-absorbing ring 114 within the flange to dissipate vibration therein.

Abstract: A cryogenic trap is shielded by a floating baffle array which is insulated from ambient temperature. The cryogenic trap includes a baffle array which is suspended by conductive braid from split cylinders. The split cylinders are cooled by respective closed cycle refrigerators.

Abstract: A downflow heat exchanger, particularly applicable as the main condenser/reboiler of a double column cryogenic air separation plant, wherein liquid distribution for uniform flow is carried out above the vapor passages and the well distributed liquid is passed into the liquid passages, preferably angularly onto the bridge fins, and then down through the liquid passages cocurrently with vapor in adjacent vapor passages.

Abstract: An air conditioning system comprises: a motor (5, 69); a speed increasing mechanism (7) connected to the motor to increase revolution speed of the motor; an air compressor (3) driven by the motor through the speed increasing mechanism at high speed to produce a high-temperature pressurized air; a cooler (11) for cooling the high-temperature pressurized air; and a turbine (9) for further cooling the pressurized air cooled by the cooler on the basis of adiabatic expansion. The rotational force of the turbine is feed-backed to the motor and the air compressor. In the air conditioning system thus constructed, since the air compressor (3) is driven by the motor (5, 69) through the speed increasing mechanism (7) in particular, it is possible to increase the pressure ratio of the air compressor and the air conditioning capacity, without increasing the size and weight of the air conditioning system.

Abstract: The present invention provides a system and method for freezing and cutting a tissue specimen for medical diagnostic purposes which comprises a specimen block holder for holding the tissue specimen; an embedding medium; a freezing plane for providing direct metal contact freezing of the specimen; a knife blade comprising a cutting edge which is substantially parallel to and may be displaced a preset distance from the freezing plane; a block holder for holding the specimen; and driving means for transporting the block holder towards the freezing plane for creating a flat frozen surface of the specimen having a thickness t and also for transporting the frozen specimen past the knife edge to provide a section having a desired thickness. The planar relationship and known distance between the freezing plane and the cutting edge together will be used as the basis for calculating frozen thickness t of the specimen. This allows for precise and automated movement of the block holder for trimming.

Abstract: A method of freezing a product, a frozen product produced thereby, and a freezing apparatus useful for performing the inventive method. The inventive method comprises the step of compressing a product to be frozen between a cooled first contacting surface and a cooled second contacting surface for a time effective for at least partially freezing the product. The inventive freezing apparatus preferably comprises: a first plate belt comprising a series of first belt freezing plates, each first belt plate having a contacting surface; a second plate belt comprising a series of second belt freezing plates, each second belt plate having a contacting surface; and a driving system for driving the plate belts.

Abstract: A detecting device having: a compressor driven by an electric signal for supplying and recovering He gas at an operation cycle of 10 Hz to 400 Hz; a He gas refrigerator for transferring the He gas to and from the compressor and expanding the tie gas to generate cold; driving power supply means for intermittently supplying a driving power to the compressor at a certain interval; and a detector to be cooled by the He gas refrigerator.