Abstract: Disclosed is an apparatus for storing and delivering a liquid cryogen. The apparatus is a dewar having a rotating liquid cryogen intake, a rotating gas supply/vent, and a rotating capacitance gauge. The rotating capacitance gauge comprises two elongated plates having outer edges shaped concentrically with the inner profile of the dewar on both ends that are electrically isolated from but fastened to one another with a small gap therebetween and electrical leads to the exterior of the dewar.

Abstract: A cryogenic meter is mounted in an insulated container having an inlet and outlet in circuit with the LNG delivery flow path. The container is filled with LNG to a level above the cryogenic meter to pre-cool it to a desired operating temperature. To maintain the level of LNG in the container during use and to separate vapor from liquid, a float device allows vapor to be returned to the storage tank from the container to refill it with LNG. Because the meter is continuously immersed in LNG during use, it is maintained at a constant temperature permitting the quantity of LNG delivered to a use device to be accurately metered. Temperature and/or pressure signals are sent to a microprocessor which computes the density of the LNG and displays the metered amount of LNG on a display.

Abstract: A system for delivering fluid, e.g. liquefied petroleum gas or "LPG", through a delivery path (10) under pressure. A delivery control valve (16) is selectably operable to close and open the delivery path (10) and monitors a parameter of the fluid, e.g. dielectric constant, and to sense the presence of vapor or gas phase in the fluid. A control means (30) responsive to the indicating signal from the sensing means (20) causes the delivery control valve (16) to close the delivery path upon sensing the presence of a significant proportion of vapor or gas phase in the fluid. A gas introduction point (35) upstream of the sensing means (20) enables gas to be introduced so as to knowingly expose the sensing means (20) to fluid containing gas phase and thereby enable controlled testing of the correct functioning of the sensing means (20).

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: A combined second relief valve and restricted orifice is located downstream of the relief valve stack on a vent line. The second relief valve opens at a pressure greater than that of the relief stack. When the second relief valve is closed, vapor is vented through the restricted orifice at high velocity, and when the second relief valve is open, the vapor vents from the unrestricted end of the vent line at high volume.

Abstract: Apparatus for cryogenic separation of elastomeric products from metallic products and textile fibers combined as composite waste products having two cryogenic chambers capable of alternately receiving waste composite products to be directly contacted by a cryogenic fluid and for alternately discharging cryogenically frozen products therefrom. The chambers are in communication through a valved duct for transferring the cryogenic fluid from one chamber to the other alternately and there is a pressure equalizing valved duct to facilitate the fluid transfer in an equalized pressure environment. The chambers are rotatable through an angle sufficient to permit the cryogenic fluid transfer to be effected by gravity from one chamber to the other alternately, so that when one of the chambers is operating as a cryogenic chamber, the other can be discharged and reloaded and vice-versa.

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: A system for compactly safely storing and delivering oxygen has a plurality of elements interconnected by fluid lines and includes a liquid oxygen tank, a filler valve and a vent valve. The new system also includes a differential pressure gauge located between and in communication with the fill valve and the vent valve to permit monitoring the pressure differential in the system so that selective adjustments can be made in a timely and controlled manner to maintain the pressure within the system during filling at an optimum level. The system also has at least one pressure relief valve, a heat exchanger, a fluid pressure regulator, an oxygen flow control outlet and a phase selector valve, to thereby permit automatic selection as a function of pressure of whether oxygen supplied from the tank to the heat exchanger will be supplied as either a liquid or a gas.

Abstract: A refueling process for cryogenic liquids, in which the cryogenic liquid in question is transferred from a storage tank into a receiving tank via a detachable line connection. Before or during the refueling process, the cryogenic liquid is cooled in the storage tank to a temperature that is below the lowest operating temperature intended in the tank and above the freezing point of the liquid. The cryogenic liquid is transferred into the tank through a filter with a fineness of 5 to 40 .mu.m, and its temperature is increased during the transfer to a value that at least approximately corresponds to the intended operating temperature in the receiving tank.

Abstract: A system for initiating the operation of a cryogenic pump wherein the suction line to the cryogenic pump and the cryogenic pump itself are brought to the proper cooldown temperature sequentially using separate temperature-based control schemes.

Abstract: An apparatus for producing and injecting a sterile cryogenic liquid (for example into a container of food) is provided, as well as a method of use of same. The apparatus includes at least one purge-swept cryogenic liquid filter, the filter including filter media having the capability to effectively sterilize cryogenic liquids, the filter media positioned within a housing to accept non-sterile cryogenic liquid and produce sterile cryogenic liquid, and to recycle an amount of the non-sterile cryogenic liquid. The apparatus further includes at least one sterile cryogenic liquid accumulator, the sterile cryogenic liquid accumulator having a sterile cryogenic liquid outlet for dispensing sterile cryogenic liquid, the sterile cryogenic liquid outlet having a passageway for a sterile cryogenic gas, whereby the sterile cryogenic gas prevents contact of the sterile cryogenic liquid with a non-sterile atmosphere via pressurization and purging during dispensing of same.

Abstract: A cryogenic gas compression system including a storage container and a gas/liquid mixer coupled to the storage container which employs a controlled flow of cryogenic liquid from the storage container to provide gas cooling action, and compressor for compressing the output gas to a high pressure. A sensor provides an indication of the gas entering the compressor and feeds it to a controller which controls the quantity of liquid cryogen fed from the storage container to the mixer.

Abstract: Apparatus and method for chilling foodstuffs in which liquid cryogen is more effectively dispersed to chill the foodstuffs and cryogenic vapor generated by the liquid cryogen is used to remove residual liquid cryogen from the apparatus and for other useful purposes including freezing the foodstuffs.

Abstract: A method and apparatus are disclosed for improving the available pump net positive suction head in a system for pumping liquid from a storage tank. When the liquid in the system is at or near its boiling point, a pump suction vessel is used to store and cool the liquid. The liquid in the pump suction vessel is kept at a temperature lower than its boiling point by surrounding the vessel with a jacketed space containing liquid from the storage tank. As the liquid in the jacketed space evaporates, the vapor is vented to the storage tank and more liquid is fed into the jacketed space.

Abstract: Cryosystem for cryogenic liquids which contain small amounts of foreign fluids with higher melting and boiling points, wherein the cryosystem comprises at least one tank, pipelines and assembly units and is used under defined gravitation conditions. The pipelines slope, at least in some areas, toward the tank, and areas of the pipelines and assembly units, from which the cryogenic liquid and the foreign fluids cannot flow back into the tank under the action of gravity, are provided with drain openings and drain lines, which open into the tank or into at least one additional collection tank.

Abstract: A reservoir for the storage of gas under high pressure comprises an enclosure portion (2) which is uninsulated and an enclosure portion (2A) which is insulated. The two portions (2A, 2B) are connected by an insulated passage (18) insulated from the enclosure portions. The uninsulated portion (2B) defines a gaseous sky limiting the instantaneous pressure drops during withdrawal of liquid from the insulated portion (2A) to decrease the response time of the heating of an external circuit to maintain pressure. Used particularly in safety installations of a principal source for the production of gas under high pressure.

Abstract: The invention relates to an insulated container (1) for storing liquid helium (2). In order to simplify the installation of a draw-off siphon and to permit drawing-off in an economical manner, according to the invention the draw-off siphon (3, 4) is at least partly fixedly integrated into the container (1) and thermally uncoupled relative to the environment.

Abstract: Cryogenic fluid piston pump functions as stationary dispensing pump, mobile vehicle fuel pump etc., and can pump vapour and liquid efficiently even at negative feed pressures, thus permitting pump location outside a liquid container. Piston inducts fluid by removing vapour from liquid in an inlet conduit faster than the liquid therein can vaporize by absorbing heat, and moves at essentially constant velocity throughout an induction stroke to generate an essentially steady state induction flow with negligible restriction of flow through an inlet port. Stroke displacement volume is at least two orders of magnitude greater than residual or dead volume remaining in cylinder during stroke changeover, and is greater than volume of inlet conduit. Cryogenic tank has a liquid compartment, a vapour compartment, and inlet and overflow conduits. Inlet conduit receives liquid from dispensing pump and widely disperses liquid into liquid tank to contact and condense vapour.

Abstract: A liquid cryogen delivery system for providing liquid cryogen to a use point, such as a freezer, at a constant temperature employing a subcooler for use disposed between the cryogen source and use point wherein expanding fluid flows countercurrently and annularly to the cryogen in a controlled manner responsive to pressure differences between the liquid and a reference pressure.

Abstract: The installation comprises an insulated storage tank (1) containing the gas in at least partially liquid form at a high pressure, a line (2) comprising a vaporizer (3) for supplying gas to a user station (A), a first cold-holding circuit (4), comprising a valve (5) and a first exchanger (6) in heat-exchange contact with the fluid in the first tank (1), and a pressure-holding line (8) comprising a second exchanger (9) and a valve (10). The system is particularly useful as a backup installation for a main gas-production source (30).

Abstract: An automated fueling facility allows untrained persons to safely dispense homogeneous phase liquid methane from a cryogenic storage tank into a motor vehicle. The fueling facility automatically maintains pressure on the liquid methane within a predetermined safe operating range using methane gas trapped in the cryogenic storage tank. The pressure on the liquid methane is at least set equal to a set pressure equal to the sum of the saturation pressure of the liquid methane plus an additional amount to help to ensure that it remains in a fully saturated condition after exposure to any pressure losses as the fluid enters the pump. A pump is cooled by placing it in the storage tank and circulating liquid methane through the pump and back into the storage tank. A dispenser, including nozzle for connecting to a motor vehicle, is cooled by circulating liquid through the nozzle and back to the storage tank through a receptacle on the dispenser to which the nozzle is connected.

Abstract: A pumping system for pumping fluids at sub-ambient temperatures where the pumping fluid, after it has been used for its analytical application, is expanded such that the energy of expansion of the pumping fluid can be employed for cooling the pump head or pumping fluid prior to pumping.

Abstract: An apparatus for dispensing a cryogenic liquid includes means for focusing a beam of energy, eg. laser energy from a source onto the liquid cryogen as it passes through an outlet from a cryogenic liquid container.

Abstract: Disclosed is an apparatus for storing and delivering a liquid cryogen. The apparatus is a dewar having a rotating liquid cryogen intake, a rotating gas supply vent, and a rotating capacitance gauge. Also disclosed is a system and a process employing the system for liquefying a gas to produce a liquid cryogen in the dewar wherein the gas is subcritically cooled and then condensed in the pressure vessel of the dewar.

Abstract: Liquid natural gas is pumped into a main tank until the main tank is completely filled with liquid. Once filled, high pressure gas is pumped into the main tank. This high pressure gas forces the liquid from the main tank into an overflow tank until the liquid level in the main tank reaches a predetermined level. High pressure gas is then pumped through the main tank to the overflow tank until the LNG in the overflow tank is saturated at a pressure slightly higher than the pressure needed at the use device. Once the desired pressure is achieved the delivery of LNG to the delivery system is stopped. LNG is initially delivered from the overflow tank to the use device as a high pressure gas. Some of the high pressure gas being delivered from the overflow tank is diverted from the use device to saturate the LNG in the main tank at the desired pressure.

Abstract: The fueling station consists of a vacuum insulated storage vessel for storing a large quantity of LNG at low pressure. The LNG is delivered to one of two relatively small volume fuel conditioning tanks where the pressure and temperature of the LNG can be raised or lowered as dictated by the needs of the system, The pressure and temperature in the fuel conditioning tanks are raised by delivering high pressure natural gas vapor thereto from a high pressure bank. The temperature and pressure can be lowered by venting natural gas from the fuel conditioning tanks and/or delivering LNG thereto.

Abstract: A cryogenic device comprises a vessel to be maintained at a cryogenic temperature. The vessel is mounted on a storage tank in a pressure Eight relationship. Cryogenic fluid under pressure is forced into the vessel through a transfer tube. The temperature in the vessel is controlled by flow of cryogenic fluid through the vessel. A throttle valve in a line leading from the cryogenic vessel regulates the cryogenic fluid flow in relation to a sensed temperature in the vessel.

Abstract: Quantities of liquid are distributed via a conduit (5) connected to a source (4) of the liquid, by periodically opening and closing a closure member (7) disposed in the conduit, and injecting, during a predetermined period, immediately after the 5 closing of the closure member (7), a quantity of gas into the conduit portion (6)immediately downstream of the closure member. The duration of the cycle between two successive openings of the closure member (7)is less than 0.1 second. The liquid is an inert liquefied gas, e.g. nitrogen or argon. The injected gas is the same as the liquefied gas and comes from a same cryogenic receptacle (1). The invention is useful for rendering inert or pressurizing containers of food products.

Abstract: A small container is filled with a mixture of oxygen and nitrogen in a predetermined and precise concentration from a source of liquid oxygen and liquid nitrogen automatically, safely, and without the possibility of a human error. The empty weight is verified. Liquid oxygen is directed to vessel. When the mass of liquid oxygen is stabilized at a preset value, liquid flow is stopped. A second pipe is cooled using liquid nitrogen, by emptying through this pipe to the atmosphere liquid nitrogen. The vessel is filled with liquid nitrogen, until the vessel is full. The correct proportion of oxygen/nitrogen is controlled.

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: The present invention produces discrete droplets of cryogenic liquid, suitable for injection into receptacles such as cans or plastic bottles, at high speeds. A container of cryogenic liquid includes a hole and an orifice, spaced apart from each other, and defining a path for liquid to flow out of the container. A conduit directs a gas into the space between the hole and the orifice. The orifice is formed in an orifice plug which can be adjusted so as to vary the volume of the space between the hole and the orifice. When gas fills the space, the gas tends to prevent the outflow of liquid. When gas is withdrawn from the space, liquid can flow out of the container. By rapidly closing opening a valve which supplies gas to the space, and by proper choice the volume of the space, the liquid can be made to fall out of the container in discrete droplets.

Abstract: In order to improve a method for filling a cryotank with liquid hydrogen, in which thermal energy is introduced into the liquid hydrogen by the transfer of the liquid hydrogen to the cryotank, such that the amount of gas which results during filling of a cryotank and is carried away via the gas return line is reduced to as great an extent as possible, preferably to zero, it is suggested that for filling hydrogen be used at a pressure and a temperature corresponding to an undercooled state of the liquid hydrogen.

Abstract: An automated fueling facility allows untrained persons to safely dispense homogenous phase liquid methane from a cryogenic storage tank into a motor vehicle. The fueling facility automatically maintains pressure on the liquid methane within a predetermined safe operating range using methane gas trapped in the cryogenic storage tank. The pressure on the liquid methane is at least set equal to a set pressure equal to the sum of the saturation pressure of the liquid methane plus an additional amount to help to ensure that it remains in a fully saturated condition after absorbing any heat during pumping from the storage tank. A pump is cooled by placing it in the storage tank and circulating liquid methane through the pump and back into the storage tank. A dispenser, including nozzle for connecting to a motor vehicle, is cooled by circulating liquid through the nozzle and back to the storage tank through a receptacle on the dispenser to which the nozzle is connected.

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 climate control system incorporated in a motor vehicle having a hydraulic pump directly driven by a vehicle engine to deliver a working oil under pressure to be supplied to either a hydraulic motor for driving a refrigerant compressor of an air-conditioning system or a heat conversion unit of the heating system via a hydraulic flow control valve for controlling the flow direction of the working oil. The air-conditioning system has an evaporator for cooling the air supplied to the vehicle compartment. In the heat conversion unit of the heating system, pressure energy of the working oil is converted to thermal energy thereof by which the engine cooling water is heated to thereby heat the air supplied to the vehicle compartment via a radiator unit made of a heater core.

Abstract: An air conditioning system for a motor crane includes a heating circuit and a refrigerating circuit The heating circuit comprises a hydraulic motor, a hydraulic pump, a radiator and a valve mechanism causing a pressure difference in the hydraulic oil flowing therethrough. The refrigerating circuit includes a compressor connected to the hydraulic motor and a condenser having a fan for forcing air thereover. The heating circuit is at least partially disposed in an air path in which the condenser is disposed. When the hydraulic oil bypasses the valve mechanism, a control device turns the fan on if the refrigerating circuit is not operating, and the temperature of the hydraulic oil sensed by the sensor reaches a predetermined temperature.

Abstract: In a combined liquid natural gas and compressed natural gas fueling station, liquid natural gas is stored in a cryogenic tank and dispensed to vehicles on demand. Compressed natural gas is produced on demand from the liquid natural gas by a high-efficiency pump and vaporizer system and dispensed directly to vehicles or stored for later dispensing. For greater efficiency, the pump and vaporizer system is powered by combustion of natural gas, including gas bled off to relieve pressure from the cryogenic tank.

Abstract: A cooling device cools a conditioned space (6) by transferring heat from the conditioned space to a working fluid (2) in a heat exchanger (4). A compressor (10) compresses the working fluid (8), which is then condensed in a condenser (14). Heat from the condenser is transferred to a dehydrogenation reaction zone (104) that includes a dehydrogenation catalyst (106) to supply a portion of an endothermic heat of reaction. The catalyst (106) is contacted with an organic hydride (102) to dehydrogenate the organic hydride to form H.sub.2 (108) and at least one dehydrogenation product (110). A combustor (112) burns the H.sub.2 (108) to form combustion products (144) that expand in a turbine (116) to drive the compressor (10). A portion of the heat of combustion is used to supply the remainder of the endothermic heat of reaction required in the dehydrogenation reaction zone (104).

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: Apparatus and methods are disclosed for lowering the temperature within a chamber from a higher actual value to a set desired lower value, the latter being stabilized by intermittently flowing liquid gas selectively through the chamber and a venting orifice, under the control of a microcomputer responding to a temperature sensor within the chamber. In one embodiment (FIG. 2), the chamber (2) and the venting orifice (11B) is supplied with coolant through separate solenoid valves (1,5) which are both open to allow maximum coolant flow rate during the initial cool-down and during the settling down stage and the approach to the steady state which follow operate with much reduced coolant flow in a coordinated intermittent mode wherein the venting orifice valve (5) is open only when extra cooling is momentarily required to assist the action of the valve (1) supplying the chamber.

Abstract: A ceramic filter containing low humidity is applied to a process for filtering of liquid nitrogen without employing a vaporizing step. An apparatus is provided for carrying out the process and includes a filter device of a ceramic filter containing relatively low humidity and having specific pore diameters and pressure regulators on both sides of the filter.

Abstract: In a tank 10 for cryogenic liquid to be used in a low-gravity environment (e.g., on a space vehicle), a liquid transfer apparatus 15 (which comprises an elongate array of fins 32 and a sponge structure formed from panels 31) functions to transfer cryogenic liquid from the interior of the tank 10 to a bowl structure 20 defining a reservoir region adjacent an outlet of the tank 10. A perforated plate 22 disposed between the sponge structure and the outlet of the tank 10 causes cryogenic liquid to pass through the outlet into an outlet line 40 in a regular and generally unbroken flow. To prevent any substantial amount of heat transfer into the reservoir region of the tank 10, the bowl structure 20 is separated from the inner surface of the tank 10 by a capillary distance in order to provide a thermally insulating space therebetween.

Abstract: Method and apparatus for delivering high pressure gas to a point of use over a wide range of flowrates by storing said gas as a cryogenic fluid, removing said cryogenic fluid by means of a single stage reciprocating piston-type pump/compressor adapted to utilize liquid, vaporized liquid, a mixture of liquid and vaporized liquid, or supercritical fluid as the inlet fluid to said pump while maintaining the inlet fluid under cryogenic conditions. Blowby from the pump is recycled to the system. Discharge fluid may also be recycled to the system.

Abstract: A method and apparatus for delivering supercritical fluids uses one or two high pressure vessels. Each vessel is cooled below the critical temperature of the fluid while the vessel is being filled. The inlet is then closed and the vessel is heated to attain a predetermined pressure. The outlet of the vessel is then opened and supercritical fluid flows from the vessel for use in various processes such as extraction or chromatography. As the fluid flows from the high pressure vessel, the pressure is controlled by adjusting the temperature of the high pressure vessel. Usually, the temperature of the vessel will be increased as the supercritical fluid exits from the vessel. When two high pressure vessels are used, the vessels can be refilled on an alternating basis so that a continuous supply of supercritical fluid can be made available as long as it is required. The high pressure vessels can be two pieces of stainless steel tubing.

Abstract: The fueling station of the invention consists of a vacuum insulated storage tank for storing large quantities of LNG at low pressure. A delivery line connects the LNG in the storage tank with a fill line to engage the use device such as a vehicle's fuel tank at the fueling station. A meter is provided to deliver a metered amount of LNG to the vehicle. A pump is used to sub-cool the LNG and convey it from the storage tank to the delivery hose and an eductor is provided to gradually draw vaporized LNG from the storage tank into the delivery line. The fill line, pump, eductor and delivery hose are vacuum jacketed to prevent vaporization of the LNG. A circulation loop is provided to sub-cool the pump, eductor and meter prior to delivering LNG to the vehicle in order to ensure that vaporized natural gas is not delivered to the use device. In an alternate embodiment a heat exchanger using LN.sub.2 or other coolant can be used in place of the pump to sub-cool the LNG.

Abstract: Method and apparatus for supplying from a vessel to a pump liquified gas with subcooling so as to avoid cavitation during pumping. A supply conduit supplies liquified gas from the vessel bottom to a pump sump which envelops the flowpath elements of a pump and the pump suction. A return conduit returns vapor and excess liquified gas from the sump to the bottom of the vessel. Heating means, preferably heat leak into the return conduit, reduces the density of the fluid in the return conduit thereby increasing the rate of liquified gas flow in the supply conduit and reducing its temperature rise enroute to the pump. Further subcooling is secured by locating the intake to the supply conduit remote from a wall of the vessel in a cooler strata of liquid, and the discharge of the return conduit proximate to a wall of the vessel in a warmer strata in the vessel.

Abstract: Methods and apparatus for economically and effectively using a portion of a liquified compressed gas feedstock, such as liquid carbon dioxide, as a refrigerant to cool said liquified compressed gas feedstock so as to prevent cavitation and liquid compressibility when pumping such feedstock are disclosed.

Abstract: A high efficiency pool heating system (10) includes a power circuit (12) and heat pump circuit (14). Each circuit having a working fluid flowing therein. In the power circuit, a heater (16) vaporizes the working fluid which is periodically delivered and exhausted through a valve section (32) to a driving section (28) of a power unit (26). The driving section drives a driven section (30) which operates as a compressor for the working fluid in the heat pump circuit. Fluid exhausted from the driven section of the power unit is passed to a first portion (48) of a heat exchanger (46) which is in fluid communication with the water of a pool. In the heat exchanger, the working fluid in the power circuit is condensed to a liquid. Thereafter, the liquid is passed through the power circuit back to the heater where it is again vaporized.

Abstract: A device for cooling a SQUID measuring instrument for measuring biomagnetic or other weak magnetic fields includes a cryostat containing a vacuum in an interior space. At least one superconducting gradiomeer and at least one associated SQUID are disposed in the vacuum. Heat-conducting connections thermally couple the superconducting gradiometer and the associated SQUID to a cryogen supplied from outside the cryostat. A carrier structure supports the SQUID and the gradiometer. The carrier structure has cooling channels through which the cryogen is forced. A cryogen supply unit is situated outside the cryostat and a cryogen transfer line couples the cryogen supply unit to the cooling channels.

Abstract: An apparatus for reclaiming contaminated refrigerant is disclosed. This apparatus contains three heat exchangers, the first of which cools the refrigerant to a temperature of less than about 32 degrees Fahrenheit, the second of which cools the refrigerant to a temperature of less than about -40 degrees Fahrenheit, and the third of which cools the refrigerant to a temperature of less than about -100 degrees Fahrenheit. The device also contains filtering means, for removing from the cooled refrigerant substantially all particles larger than about 0.1 microns. The device also contains gas removing means, for removing noncondensable gas from the filtered refrigerant.