Abstract: A vacuum pump of the steam-ejector type uses steam generated by the combustion of hydrogen and oxygen. The mass of ejected steam is increased, and the temperature of the ejected steam is reduced, by injection of water into the combustion product. Propellant densification is accomplished by using such a vacuum pump to reduce the vapor pressure of a cryogenic liquid, thereby reducing its temperature. The cryogenic liquid may be the propellant, or it may be a coolant medium thermally coupled to the propellant.

Abstract: The invention comprises a system for supplying carbon dioxide liquids while maintaining a desirable pressure in a liquid carbon dioxide storage vessel. In an exemplary embodiment, an improved vaporizer is deployed in a downstream line from the storage vessel. The vaporizer converts a portion of the withdrawn liquid carbon dioxide into replacement carbon dioxide vapor using heat from steam or electricity supplied by the facility. This replacement carbon dioxide vapor is returned to the storage vessel to maintain the desired internal tank pressure as liquified carbon dioxide is withdrawn. The vaporizer includes an elongated cylindrical steel shell with spaced apart ends. Each end has a steel end cap that is welded to the body. Either end cap may be removed to service the vaporizer. The vaporizer body is penetrated by three ports, a steam inlet, a liquid carbon dioxide inlet and a carbon dioxide vapor outlet.

Abstract: A non-azeotropic refrigerant is described comprising (A) carbon dioxide (CO.sub.2), (B) pentafluoroethane (R-125), (C) 1,1,1-trifluoroethane (R-143a) and (D) chlorodifluoromethane (R-22).

Abstract: A process for treating a workpiece. The workpiece is cooled by directing toward the workpiece a material that includes a gas and particles of a material that undergoes a phase change when applied to the workpiece. The gas and the particle material are non-reactive with the workpiece during the cooling.

Abstract: A process for using the cold of pressurized liquefied natural gas (PLNG) to compress boil-off vapors produced by handling of liquefied natural gas to produce a higher pressure gas product and at the same time produce power that preferably provides at least part of the power for the process. The PLNG is pressurized, passed to a first heat exchanger for vaporization, and the vaporous material is passed to a second heat exchanger for further heating to produce a first gas product. A refrigerant is circulated in a closed cycle through the first heat exchanger to heat the PLNG, through a pump to pressurize the refrigerant, through a second heat exchanger to vaporize the refrigerant, and through a work-producing device to generate energy. Boil-off gas is compressed and passed through the first heat exchanger, further compressed, and then passed through the second heat exchanger to produce a second gas product.

Abstract: A method for determining the composition of a ternary refrigerant in a refrigeration system. The method calculates the composition of the ternary refrigerant under the assumption that the expansion cycle is isenthalpic and that the ratio of two components in the ternary mixture remain fixed in relation to one another before and after the expansion. These assumptions permit the calculation of composition of a ternary mixture with relatively few inputs.

Abstract: Provided is a novel system and method for delivery of a gas from a liquified state. The system includes: (a) a compressed liquified gas cylinder having a gas line connected thereto through which the gas is withdrawn; (b) a gas cylinder cabinet in which the gas cylinder is housed; and (c) means for increasing the heat transfer rate between ambient and the gas cylinder without increasing the temperature of the liquid in the gas cylinder above ambient temperature. The apparatus and method allow for the controlled delivery of liquified gases from gas cabinets at high flowrates. Particular applicability is found in the delivery of gases to semiconductor process tools.

Abstract: Apparatus and methods for improving efficiency of a temperature conditioning system which employs a cryogenic liquid. A vapor powered ventilation motor is normally powered by vapor from the low pressure end of the evaporation coils. However, supplemental vapor is provided at start-up to provide immediate ventilation. In addition, vapor which bleeds off valves is cycled through the vapor powered motor or used to maintain a slight positive pressure when the system is shut down.

Abstract: A heat pump system, utilizing a multi-component refrigerant blend in which a low pressure component is zeotropic with respect to the remainder of the blend, separates the low pressure component by rectification to enhance heating capability in low ambient temperatures. Vapor is separated from liquid in the effluent of the condenser of a heat pump, at a pressure in equilibrium at a temperature midway between the evaporator and condenser effluent temperatures, the vapor being applied to an auxiliary inlet at a mid pressure point in the compression stroke of the compressor.

Abstract: Fuel storage and delivery systems are provided for storing pressurized liquefied natural gas (PLNG) fuel at a pressure of about 1035 kPa (150 psia) to about 7590 kPa (1100 psia) and at a temperature of about -123.degree. C. (-190.degree. F.) to about -62.degree. C. (-80.degree. F.) and delivering vaporized PLNG fuel on demand for combustion in an engine. The fuel storage and delivery systems have fuel storage containers that are constructed from ultra-high strength, low alloy steel containing less than 9 wt % nickel and having a tensile strength greater than 830 MPa (120 ksi) and a DBTT lower than about -73.degree. C. (-100.degree. F.). While not limited thereto, the present invention is especially useful for automobiles, buses, trucks and other vehicles with engines designed to operate through combustion of natural gas.

Abstract: A method and apparatus for providing a clean respirable atmosphere in a clean room. A liquefied breathable gas is supplied from a source thereof and filtered. The filtered liquid is vaporised and the gas produced by the vaporisation is filtered. Thereafter the filtered gas is introduced into the clean room.

Abstract: A cooling device for rapidly cooling items, such as biological samples. The cooling device includes an enclosure having a chamber and an air circulation path at least partially within the chamber. A fan is operatively connected to the chamber for circulating air within the air circulation path and a perforated tube is disposed within the air circulation path for receiving a liquid refrigerant under pressure and distributing refrigerant in gaseous form to the air circulation path. Preferably the perforated tube is formed as a coil having multiple revolutions and either an axial blade fan or a centrifugal fan is received generally within the coils.

Abstract: A cryogenic liquid transfer system, for servicing a use device, releases stored cryogen from a bulk storage tank to a gas supply tank and a dispenser tank. The liquid cryogen in the gas supply tank is circulated through a circuit that includes a heat exchanger and the gas thus generated is returned to the gas supply tank so as to pressurize it. The pressurized liquid cryogen is released from the gas supply tank so that it flows through a vaporizer. The gas produced by the vaporizer is bubbled through the liquid cryogen in the dispenser tank so as to raise its temperature and pressure to the level required by the use device being serviced. Gas from the vaporizer is then delivered to the space above the liquid cryogen in the dispenser tank to as to create a pressure head that will cause the liquid cryogen to flow to the use device upon release. A venturi is connected to the tubing between the gas supply tank and the dispenser tank and is used to reduce the pressure in the bulk storage tank.

Abstract: A refrigerating system, using CO.sub.2 as a refrigerant, for an air conditioner for an automobile. A pressure at the outlet of the heat emitter 2 is controlled to a target value in accordance with the temperature of the refrigerant at the outlet of the heat emitter for obtaining an operation of the refrigerating system along the optimum control line .eta..sub.max. A pressure reducer 4 and a cooler 5 are provided on a branched passageway 28 branched from a refrigerant recirculating passageway 27 for injection. The cooler 5 is for obtaining a heat exchange between a flow of the refrigerant on the branched passageway 28 after being cooled by the pressure reducer and a flow of the refrigerant on the main passageway 27, thereby cooling the refrigerant directed to the evaporator. In a second aspect of the invention, a means is provided for increasing a target value of the pressure at the pressure reducer when a thermal load of the refrigerating system is high.

Abstract: A method of charging and recharging a refrigerant loop with a ternary refirgerant composition, wherein substantially equal proportions of difluoromethane and pentafluoroethane are added to the loop in substantially equal proportion by mass, during the step of charging and recharging.

Abstract: A refrigerant circulation system of the present invention includes a compressor, a condenser, a evaporator, a throttle device and a control unit. The control unit controls a composition of a refrigerant circulating in the refrigerant circulation system based on a temperature and pressure of the refrigerant of an inlet and outlet portion of the compressor, condenser, evaporator and throttle device. The control unit controls to open and close the throttle device to change the composition of the refrigerant circulating in the refrigerant circulation system.

Abstract: A method and apparatus for pressurizing a high purity gas in liquefied form to an ultra high pressure gas in vapor form using a constant volume, heated vaporization vessel.

Abstract: In a heat transfer tube for a zeotropic refrigerant mixture, the inner surface of the tube in which the zeotropic refrigerant mixture flows is formed with grooves having cross portions where the grooves intersect with each other, or the inner surface of the tube is formed with a plurality of independent projections. Thus, concentration boundary layers generated in the zeotropic refrigerant mixture are stirred to reduce the thickness of the concentration boundary layers, thereby decreasing the diffusion resistance and promoting the stirring effect. Consequently, there can be provided a heat transfer tube for a zeotropic refrigerant mixture which exhibits a high heat transfer performance, and a heat exchanger of a cross-fin tube type, a refrigerator and an air conditioner which include such heat transfer tubes.

Abstract: A method, and apparatus for implementing the method, utilize cryogenic fluids to cool a fluid. The method includes receiving and allowing expansion of a first compressed cryogenic fluid within a chamber; flowing a second fluid past said chamber; and allowing the transfer of heat between the chamber and the second fluid. The method may further include maintaining the second fluid at a predetermined temperature by controlling the transfer of heat between the chamber and the second fluid. The apparatus includes a chamber for receiving therein and allowing expansion of a compressed cryogenic fluid. The chamber includes at least one wall formed of a material having a high thermal conductivity and high resistivity to low temperature. The chamber may include an insert for receiving cryogenic fluid therein and dispersing the cryogenic fluid through a plurality of holes into the chamber. The apparatus may also include a fluid path component for circulating therethrough the second fluid.

Abstract: In order to modify the composition of a non-azeotropic mixed refrigerant circulating through the refrigeration cycle of a refrigerating and air-conditioning apparatus using a refrigerant rectifier column, the level of the liquid refrigerant rich in the low-boiling point fraction that is obtained from a refrigerant rectifier column (11) and which collects in a refrigerant container (14), as well as the level of the liquid refrigerant rich in the high-boiling point fraction that collects in an accumulator (6) are adjusted so as to modify the composition of the refrigerant circulating through the refrigeration cycle. The circuit structure can be made simple, and the energy need not be supplied during the cooling and heating operations to modify the composition of the non-azeotropic mixed refrigerant.

Abstract: A method and apparatus for storing and dispensing a liquid consisting of an oxygen containing mixture so that the liquid will not contain any more than a predetermined concentration of the oxygen at a predetermined pressure. In accordance with the invention, the mixture is introduced into the container at a specified initial concentration. A hypothetical volume of the saturated state of the liquid having the initial concentration is computed that when expanded into the total volume of the container, the resulting liquid would have the maximum enrichment. The liquid is dispensed from a bottom region of the container and dispensing is prevented when the liquid remaining within the container could possibly have the maximum enrichment computed at a particular dispensing pressure. Pressure relief methods are employed that avoid head space vapor being vented.

Abstract: In the detection of circulating compositions in the cycle of a non-azeotropic refrigerant composed of three or more kinds of refrigerants, there have been drawbacks in that the number of sensors required is large, and large errors are contained in the circulating composition which can be detected. To overcome these drawbacks, the refrigerating and air-conditioning apparatus comprises at least a compressor, a condenser, a pressure reducing device, and an evaporator, and in a refrigerant cycle which uses as a working refrigerant a non-azeotropic refrigerant composed of N kinds (N.gtoreq.3) of refrigerants and is provided with composition detecting means for detecting the circulating compositions of the non-azeotropic refrigerant, circulating compositions are determined by using (N-2) relations on compositions among a first component to a j-th (2.ltoreq.j.ltoreq.N-1) component of the non-azeotropic refrigerant.

Abstract: A refrigerant circulation system of the present invention includes a compressor, a condenser, a evaporator, a throttle device and a control unit. The control unit controls a composition of a refrigerant circulating in the refrigerant circulation system based on a temperature and pressure of the refrigerant of an inlet and outlet portion of the compressor, condenser, evaporator and throttle device. The control unit controls to open and close the throttle device to change the composition of the refrigerant circulating in the refrigerant circulation system.

Abstract: A system for providing a fluid refrigerant to a cooling element is provided herein. The system includes a vessel which holds the fluid refrigerant, a heat source evaporating a portion of the fluid in the vessel, and a heat exchanger condensing a portion of the gaseous phase of the fluid in the vessel. A conduit establishes fluid communication between: (i) the vessel and the cooling element; and (ii) the cooling element and the heat exchanger. Importantly, the system controls the flow rate of the fluid refrigerant to the cooling element by controlling the pressure of the fluid in the vessel. The system is particularly useful with cryogenic fluid refrigerants to cool a superconductor for an MRI System.

Abstract: A food processing plant includes a food processing apparatus. The food processing apparatus including a device for setting set-point parameters for operation of the apparatus and a device for controlling operation of the apparatus based on the set-point parameters. The plant also includes a device for acquiring information relating to actual operation of the food processing apparatus, a unit for monitoring the apparatus, the unit being located remote from the apparatus and including a device for detecting anomalies in operation of the apparatus, and a device for communicating the information relating to the actual operation of the apparatus from the apparatus to the remote monitoring unit.

Abstract: A control-information detecting apparatus for a refrigeration air-conditioner using a non-azeotrope refrigerant is equipped with a temperature detector and a pressure detector at the refrigerating cycle of the air-conditioner, which cycle is formed by connecting a compressor, a condenser, a decompressing device, and an evaporator, to detect the temperature and the pressure of the refrigerant circulating the cycle for obtaining the circulation composition of the refrigerant with the composition computing unit thereof. The usual optimum operation of the cycle is thereby enabled even if the circulation composition of the refrigerant has changed.

Abstract: An apparatus and method wherein ozone layer-damaging dichlorodifluoromethane is substituted with a mix of less environmentally damaging refrigerants chlorodifluoroethane and tetrafluoroethane in dichlorodifluoromethane-based air-cooling systems. While less environmentally damaging than dichlorodifluoromethane, the substitute refrigerant has a temperature-pressure relationship similar to that of dichlorodifluoromethane, making the substitute refrigerant suitable for use with dichlorodifluoromethane-based air-cooling systems. The substitute refrigerant can be used alone or in combination with dichlorodifluoromethane. In either event, it is mixed with a relatively small percentage of a hydrophobic lubricating oil which is compatible with both the substitute refrigerant and with dichlorodifluoromethane.

Abstract: A heat exchanger unit having a housing into which a cryogenic liquid is introduced and permitted to evaporate and vaporize into a cryogenic cold gas. A process fluid to be cooled flows in a heat exchanger and heat exchange to cool the process fluid takes place between the cold gas and the heat exchanger, without making direct contact between the cryogenic liquid and the heat exchanger which would cause freezing. The refrigerating capacity of the cryogenic cold gas is replenished by heat exchange contact with the evaporating cryogenic liquid.

Abstract: A device for pressurizing a tank containing a supply of cryogenic liquid features a tubular enclosure disposed within the cryogenic liquid. The tubular enclosure features an opening in its bottom and is in communication with a pressure builder coil external to the tank. The vapor side of the pressure builder coil is in communication with the head space of the tank. An electric heater element is disposed in the bottom of the tubular enclosure. An insulating tube may optionally be disposed about the tubular enclosure. In addition, a ball may optionally be positioned adjacent the opening in the tubular enclosure so that a check valve is formed. The device fits through the tops of existing cryogenic tanks.

Abstract: A system for rapidly filling cylinders with gas while avoiding superambient temperature excursions of the cylinder contents wherein cylinder charging gas is produced by vaporizing pressurized cryogenic liquid in admixture with pressurized gas to simultaneously in one step produce the charging gas and control the temperature of the charging gas to enable the subsequent rapid filling rate.

Abstract: The proposed gas generator includes an isothermal vessel for a cryogenic liquid, the vessel being connected via an electrically controlled valve to a supercharging evaporator, a nozzle unit arranged in the upper part of the gasifier and connected by an electrically controlled valve to the lower part of the cryogenic liquid vessel, the gasifier being partially filled with a heat-accumulating substance and provided with a deflector situated above the nozzle unit and an electrically controlled sealing unit; in the lower part along the gasifier axis are provided a separator and a toroidal elastic casing attached to the bottom of the gasifier, the cavity of the casing communicating via the main pipe (provided with a pre-heating heat exchanger) with the upper part of the iso-thermal vessel, while the heat-accumulating substance is situated above the surface of the toroidal elastic casing, the electrically controlled sealing unit being situated at the separator outlet.

Abstract: In a refrigerating cycle (air conditioner) using mixture refrigerant, a mixing ratio of the refrigerant in a refrigerant circuit is measured by a mixing ratio detector, and a controller receives the detection signal to open a control valve when the mixing ratio of a high boiling-point refrigerant component is low, whereby the high boiling-point refrigerant stocked in a liquid reservoir is returned to the refrigerant circuit. The high boiling-point refrigerant which is supplied from the liquid reservoir through the opening operation of the control valve is supplied from a low pressure side of a compressor into the refrigerant circuit to keep the mixing ratio of the refrigerant circulating in the refrigerant circuit to a predetermined value, thereby preventing abnormal increase of pressure of the refrigerant due to variation of the mixing ratio.

Abstract: A system delivers cryogenic gas at a high pressure from a supply of cryogenic liquid maintained at a low pressure in a bulk tank. The bulk tank supplies liquid to at least one transfer tank. The transfer tank is pressurized by connecting it to a pressure building tank contaning gas at a high pressure. A heat exchanger is connected in circuit between the transfer tank and the pressure building tank. The transfer tank provides liquid at a high pressure to the heat exchanger so that a vapor is produced. This vapor is fed to the pressure building tank so that the high pressure therein is maintained. The transfer tank provides a high pressure flow of liquid to a vaporizer and a high pressure gas storage tank so that high pressure cryogenic gas may be produced and stored.

Abstract: A control method is provided for a cryogenic refrigeration system having an evaporator-heater coil, an electronically controlled valve for regulating the amount of cryogen to the coil, and a vapor motor driven by the cryogen that is coupled to both an alternator for recharging a battery, and a fan for generating a discharge air flow through the coil and into a conditioned space. The shaft rpms of the vapor motor is determined by a rectified output of the alternator, and the electronically controlled valve is incremented or decremented so that the shaft rpms stay above a preselected amount sufficient to both to recharge the battery of the system, and to circulate sufficient air in the conditioned space to avoid undesirable temperature non-uniformities therein. The pressure of the cryogen in the system is further continuously measured, and the electronically controlled valve is incremented or decremented in order to maintain a sufficient pressure to maintain the cryogen in a gaseous state.

Abstract: In order to deliver ultrapure helium to a utilization line (1), helium is withdrawn, in liquid or supercritical form, from a storage tank (3), it is filtered in this liquid or supercritical form (at 4), the filtered helium is vaporized and the resulting helium gas is sent to the utilization line (1). The process is applicable to the cooling of integrated-circuit wafers.

Abstract: Disclosed is a refrigeration or air conditioning system comprising a refrigeration cycle that uses a refrigerant mixture of at least two kinds of refrigerants consisting of 45 to 55 weight percent of R32 and 55 to 45 weight percent of R125, and that includes at least a compressor, a condenser, a throttling device, and an evaporator. In some cases the temperature and pressure in a line leading from the inlet of the evaporator to the suction port of the compressor is controlled below a specific temperature and pressure point corresponding to the critical decomposition point of a clathrate that contains water as a host solution and the refrigerant mixture as guest molecules, and within a prescribed control range bounded by a formation limit line of the clathrate and a saturated liquid pressure line representing the pressure versus temperature relationship of saturated liquid of the refrigerant mixture (a first control mode), and a dryer for moisture removal is provided in the refrigeration cycle.

Abstract: Methods and systems of delivering ultra-high purity gas to a point of use are claimed and described. The methods include providing a source of ultra-high purity liquid (the source preferably at a pressure and temperature sufficient to maintain the liquid in substantially the liquid phase); transporting (preferably via pressure in the source alone) the ultra-high purity liquid from the source to one or more means to effect a phase change of the ultra-high purity liquid to an ultra-high purity gas; effecting a phase change (preferably at or near equilibrium vaporization conditions) of the ultra-high purity liquid to form an ultra-high purity gas in the one or more means to effect the phase change; and routing the ultra-high purity gas from the means to effect the phase change to a point of use (preferably with no intermediate, potentially impurity-generating media between the means to effect the phase change and the point of use other than ultra-clean conduit).

Abstract: A refrigerating system of vapor compression type operating at a super critical area, while obtaining an increased efficiency. The refrigerating system includes a pressure control means for controlling the temperature and the pressure at the outlet of a heat emitter. The pressure control valve responds to a pressure difference between the inlet pressure of the refrigerant to the pressure control valve and the pressure in an outwardly sealed chamber in which the refrigerant is filled such that, with respect to the volume of the chamber under closed condition of the pressure control valve, a density of the refrigerant is in a range between a density of a saturated liquid at a temperature of 0.degree. C. and a density at the critical point of the refrigerant. As a result, the pressure and the temperature at the outlet of the heat emitter is controlled substantially along the optimum control line .eta.max, resulting in an effective execution of a refrigerating cycle at the critical area.

Abstract: A refrigeration system (12) is comprised of three expansion units (19A, 19B, 19C), with each having an expansion chamber (22) and three secondary chambers (24, 26 and 28), connected to a supply (16) of compressed refrigerant. The expansion chamber and secondary chambers are formed with progressively reducing volumetric capacity. The end of each of the the secondary chambers, is connected to a common bleed tube (29) having a bleed hole (34) for venting the refrigerant. The bleed hole opens to the outside of a housing (15) which houses the expansion units. The interior of the housing (15) is filled with a gel which changes state from a liquid to a solid at a predetemmined temperature. A valving arrangement (32) connects the expansion units to a supply of compressed refrigerant. The housing (15) together with a supply (16) refrigerant can be installed into a cooling box for cooling the space within the cooling box.

Abstract: An apparatus and method of heat exchange in which a liquified gas is evaporated in a first coil disposed in a fluid heat exchange medium in a heat exchanger, absorbing heat by the evaporating liquid to chill the heat exchange medium, disposing in the heat exchange medium in the heat exchanger a second coil containing heat exchange medium in fluid connection with a body of heat exchange medium contained in a reservoir, chilling the heat exchange medium in the heat exchanger and circulating chilled heat exchange medium to the reservoir and from the reservoir to a facility location needing cooling, returning warmed heat exchange medium from the facility location to the reservoir and thence to the second coil for rechilling and reuse.

Abstract: Current self-contained gas delivery systems that provide gas vapor from a liquefied gas source such as odorized liquid propane consist of a single tank, or container. Both liquid and gas are contained in this tank. Fuel gas is supplied to the user from the vapor phase above the liquid. Boil off from the liquid phase to replace the withdrawn vapor phase results in low initial odorant levels, which increase to very high levels as the liquid is used up. This invention corrects this problem by the addition of a second tank or a second compartment within the first tank. The second tank or compartment, which contains gas phase only, is connected to the first compartment containing the liquefied gas by a small-diameter tube immersed in the liquid phase. The second compartment is positioned or valved in such a way that no liquid will accumulate in the compartment. The gas delivery valve to the gas user is located on the second, or vapor-phase-only container.

Abstract: An air conditioner including at least two kinds of refrigerant which are circulated in a refrigerant circuit and have different characteristics, a calculator for calculating the driving capacity of a compressor in accordance with a request load of the refrigerant circuit and outputting a driving capacity signal representing the driving capacity, a driving unit for controlling the driving capacity of the compressor so as to obtain the driving capacity corresponding to the driving capacity signal of the calculator, and correcting means for correcting the driving capacity signal so as to reduce the driving capacity when the refrigerant pressure in the refrigerant circuit exceeds a first pressure value.

Abstract: In a refrigerating cycle in which a constant speed type compressor, an indoor heat exchanger and an outdoor heat exchanger are connected one by one by means of piping, a receiver is provided between the indoor and outdoor heat exchangers, and no capacity control mechanism is provided for the compressor, a gas-liquid flow rate regulating device is associated with the receiver for regulating at least either of liquid flow rate and gas flow rate of a cooling fluid which flows into and out of the receiver. This causes a quantity of excess refrigerant stored in the receiver to change to thereby vary an effective quantity of refrigerant circulating through the refrigerating cycle.

Abstract: A heat pump system has a separate outdoor coil which is mounted below the primary outdoor coil and connected in parallel with it by valves. On system start up in the heating mode, the inlet of the auxiliary coil is closed, and the outlet is opened so that compressor vacuum will boil off the more volatile, high pressure components thus filling the system. The outlet valve is then closed trapping the low pressure component in the auxiliary coil. In a second embodiment, the accumulator is utilized to assist the auxiliary coil in vacuum separation of the refrigerant blend. Variants include blocking flow through the expansion valve on start up.

Abstract: A heat exchanger device, comprising a first heat exchanger for evaporation of liquid natural gas (LNG), and a second heat exchanger for superheating of gaseous natural gas (NG). The heat exchangers (1) are arranged for heating these fluids by means of a heating medium and have an outlet which is connected to a mixing device (20) for mixing the heated fluids with the corresponding unheated fluids. According to the invention the heat exchangers (1) comprise a common housing (2), in which there are provided separate passages (7, 8) for the fluids. The mixing device (2) constitutes a unit together with the housing (2) and has a single mixing chamber (23) with one single fluid outlet (30). In separate passages (7, 8) there are provided valves (10, 26) and (13, 28) respectively for the supply of LNG or NG in the housing (1) and the mixing chamber (23).

Abstract: A high pressure pumping system for pumping cryogenic liquid from a low pressure holding cylinder to a high pressure gas cylinder (or other high pressure utilization system) includes a high pressure piston pump having a unidirectional flow input and a unidirectional flow output, immersed in the cryogenic liquid in a low pressure pump container that is fed cryogenic liquid from the low pressure holding cylinder, the pressure in said pump container being maintained so that driving the pump piston pumps cryogenic liquid from the bulk tank to the high pressure utilization system.

Abstract: A refrigerating apparatus employs a mixture of coolants and a coolant controller for controlling a ratio between the coolants to adjust refrigerating capacity during a refrigerating operation. The apparatus has a compressor whose revolution speed is controlled to provide required refrigerating capacity. When the revolution speed of the compressor decreases below a lower set value or rises above an upper set value, the coolant controller controls the ratio between the coolants.

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: The delivery system of the invention consists of a pair of LNG fuel tanks mounted on a vehicle. A solenoid valve associated with each tank allows the vehicle operator to select the tank from which LNG is to be delivered to the engine. An automatic override system is provided whereby if the pressure in the non-selected tank rises above a predetermined level, the operator's tank selection is overridden and gas from the non-selected tank is used until the pressure falls below the predetermined level. This override system eliminates the need to vent gas to the atmosphere to avoid pressure building up and thereby eliminates waste of the LNG. Each tank is also provided with a pressure building capability such that the gas will always be delivered to the engine with sufficient pressure. The system is designed such that LNG from a stationary low pressure storage tank can be delivered at high pressure to refuel the tanks.

Abstract: The invention in its preferred embodiment is a portable life support system providing the wearer of a garment with temperature regulation and a breathable atmosphere using cryogenic technology. Wherein a liquid cryogen is vaporized by heat exchange with the wearers body and the vaporized cryogen is delivered to the wearer as a breathable atmosphere.