Abstract: A system and method for cooling a liquid cryogenic fluid user with an inert and non-pressurized liquid cryogen in 120K to 200K temperature range is provided. This includes maintaining the first liquid cryogenic fluid within a first predetermined temperature range with the sub-cooler and/or the recirculation pump, maintaining the second liquid cryogenic fluid within a second predetermined temperature range with the heat exchanger, and recondensing the second liquid cryogenic fluid using the pressurized first liquid cryogenic fluid.

Abstract: A method for increasing the reliability and availability of a cryogenic fluid reliquefaction system is provided. Wherein the liquid cryogenic fluid is supplied to a cryogenic liquid user in the absence of a pump by elevating the storage height of the main cryogenic storage tank relative to the liquid cryogenic liquid user to a minimum predetermined height. Wherein the temperature of the liquid cryogenic fluid downstream of the sub-cooler is at least 1 degree Celsius above the freezing point of the cryogenic fluid at the internal pressure. The method also includes controlling the internal pressure of the main cryogenic tank by adjusting the recirculation flow to the, and maintaining the cold supply to the liquid cryogenic fluid user when the sub-cooling line is reduced or stopped by venting the vaporized cryogenic fluid.

Abstract: A method for increasing the reliability and availability of a cryogenic fluid reliquefaction system is provided. It may comprise at least N sub-coolers comprising a motor and a compressor and at least one variable speed. It may comprise N?1 variable speed systems to be shared between the motors and compressors if N equals 2, or N?2 variable speed systems to be shared between the motors and compressors if N is greater than 2. It may comprise two different liquid cryogenic fluid users are provided liquid cryogenic fluid, utilizing two different main cryogenic tanks, with a common sub-cooler and recirculation loop, wherein the pressure in the two different main cryogenic tanks are controlled with pressure controllers acting on two different subcooled liquid cryogenic fluid valves. And or, it may comprise at least one liquid cryogenic fluid user is provided refrigeration from two or more sub-cooling systems in a lead-lag arrangement.

Abstract: A device for refrigerating and/or liquefying a working gas comprising helium, the device comprising a looped working circuit for the working gas includes, in series, a compression station, a cold box, a heat exchange system exchanging heat between the cooled working gas and a user, the device further comprising an additional pre-cooling system comprising at least one tank of auxiliary cryogenic fluid, such as liquid nitrogen, the cold box comprising a first cooling stage of the working gas comprising a first exchanger disposed at the output of the compression station as well as a second heat exchanger and a third heat exchanger, the first heat exchanger being of the aluminum plate-fin type, the second heat exchanger being of the tube or welded plate type, characterized in that the second and third heat exchangers are connected both serially and in parallel on the working circuit downstream of the first heat exchanger.

Abstract: Refrigeration device comprising a working circuit in a loop for the working gas and comprising, in series: a compression station, a cold box, a system for the exchange of heat between the cooled working gas and a point of use, a system for the additional pre-cooling of the working gas leaving the compression station comprising an auxiliary cryogenic fluid volume, the cold box comprising a first cooling stage for the working gas comprising a first and a second heat exchanger, these being connected both in series and in parallel to the working circuit at the outlet of the compression station, the first cooling stage also comprising a third heat exchanger selectively exchanging heat with the auxiliary fluid, characterized in that the third heat exchanger is connected both in series and in parallel to the first and to the second heat exchangers, the working circuit comprising a recuperation pipe fitted with at least one valve and which connects the outlet of the third heat exchanger to the second heat exchanger.

Abstract: A device for refrigerating and/or liquefying a working gas comprising helium, the device comprising a looped working circuit for the working gas includes, in series, a compression station, a cold box, a heat exchange system exchanging heat between the cooled working gas and a user, the device further comprising an additional pre-cooling system comprising at least one tank of auxiliary cryogenic fluid, such as liquid nitrogen, the cold box comprising a first cooling stage of the working gas comprising a first exchanger disposed at the output of the compression station as well as a second heat exchanger and a third heat exchanger, the first heat exchanger being of the aluminum plate-fin type, the second heat exchanger being of the tube or welded plate type, characterized in that the second and third heat exchangers are connected both serially and in parallel on the working circuit downstream of the first heat exchanger.

Abstract: Refrigeration device comprising a working circuit in a loop for the working gas and comprising, in series: a compression station, a cold box, a system for the exchange of heat between the cooled working gas and a point of use, a system for the additional pre-cooling of the working gas leaving the compression station comprising an auxiliary cryogenic fluid volume, the cold box comprising a first cooling stage for the working gas comprising a first and a second heat exchanger, these being connected both in series and in parallel to the working circuit at the outlet of the compression station, the first cooling stage also comprising a third heat exchanger selectively exchanging heat with the auxiliary fluid, characterized in that the third heat exchanger is connected both in series and in parallel to the first and to the second heat exchangers, the working circuit comprising a recuperation pipe fitted with at least one valve and which connects the outlet of the third heat exchanger to the second heat exchanger.

Abstract: A device for refrigerating and/or liquefying a working gas comprising helium, the device comprising a looped working circuit for the working gas includes, in series, a compression station, a cold box, a heat exchange system exchanging heat between the cooled working gas and a user, the device further comprising an additional pre-cooling system comprising at least one tank of auxiliary cryogenic fluid, such as liquid nitrogen, the cold box comprising a first cooling stage of the working gas comprising a first exchanger disposed at the output of the compression station as well as a second heat exchanger and a third heat exchanger, the first heat exchanger being of the aluminum plate-fin type, the second heat exchanger being of the tube or welded plate type, characterized in that the second and third heat exchangers are connected both serially and in parallel on the working circuit downstream of the first heat exchanger.