Abstract: A method for producing a sterile cryogenic fluid is disclosed. A warm gas stream is sterilized by filtration and fed to a heat exchanger resulting in a cryogenic sterile fluid being formed. The waste gas stream from the heat exchanger is fed to a second filtration unit and the warm sterile waste gas stream is fed to a second heat exchanger to produce more cryogenic sterile fluid, resulting in a more efficient use of gases employed in the sterilization process.

Abstract: The invention relates to a method for extinguishing a smouldering fire in a silo by introducing inert gas into the silo. The inert gas is introduced through a venturi-type nozzle above the stored content in the silo with a slow streaming velocity in such a way that mass ratio of the entrained surrounding gas to the incoming liquid inert gas is between 0.5 and 20. Thus a closed inert gas layer is formed above the smouldering fire.

Abstract: The invention relates to a method for extinguishing a smouldering fire in a silo by introducing inert gas into the silo. The inert gas is introduced through a venturi-type nozzle above the stored content in the silo with a slow streaming velocity in such a way that mass ratio of the entrained surrounding gas to the incoming liquid inert gas is between 0.5 and 20. Thus a closed inert gas layer is formed above the smouldering fire.

Abstract: Backup refrigeration is provided to a cryogenic refrigeration system comprising multiple cooling loops using a single backup coolant storage vessel. The backup coolant storage vessel is in fluid communication with at least one of the cooling loops, and the cooling loops are in fluid communication with each other. Each cooling loop, in turn, is in fluid communication with a refrigeration unit. In the event of lost coolant from one of the loops, coolant, e.g., liquid nitrogen, is transferred from the other loops to the loop that lost coolant, and the backup coolant storage vessel releases backup coolant into the system.

Abstract: Apparatus for producing liquid or solid xenon comprises a duct 12 having an inlet 14 for receiving gaseous xenon and an outlet 16 for outputting gaseous xenon at a reduced temperature to a nozzle located in a vacuum chamber 60. A housing 18 extends about the duct and contains a halocarbon coolant in thermal contact with the duct, and a second duct 24 in thermal contact with the halocarbon coolant for conveying a flow of liquid nitrogen through the housing 18 to control the temperature of the halocarbon. In view of the difference in the pressure of the xenon gas output from the duct and the pressure in the chamber, the thus-cooled gas is caused to liquefy or solidify in the vicinity of the nozzle.

Abstract: A vacuum pumping system comprises a first gas supply for supplying a first gas, such as xenon, to a vacuum chamber. A pump receives the gas output from the chamber. A second gas supply supplies a purge gas, such as nitrogen or helium, for pumping with the first gas. A gas separator receives the pumped gases exhausted by the pump, and recovers the first gas and the purge gas from the stream. The recovered first gas is recirculated through the vacuum chamber, and the recovered second gas is recirculated through at least the pump.