(WO9848227-A1)      A new process liquefies a hydrocarbon-rich stream, especially containing natural gas. Heat is removed by indirect exchange with coolants, in a mixed coolant circuit cascade. The cascade circuit coolants, have at least three different compositions. The first circuit pre-cools, the second liquefies and the third sub-cools the stream being liquefied. The new feature is cold-induction compression (P3, L3, S3) of the vaporised and superheated coolant mixture.    USE -   To liquefy especially natural gas, producing this LNG by indirect heat exchange.    ADVANTAGE -   This new process has a reduced specific energy consumption in comparison with prior art. For the same duty, the plant is both smaller and costs less. The use of cold-induction compressor sections means that the coolant vapour does not have to be heated to ambient temperature before compression, increasing efficiency. This also cuts down the heat exchange area required; so smaller, lower cost exchangers can be specified. Functions of the interlaced cooling circuits are clarified in the text. An increase in thermodynamic efficiency results from optimal matching of the circuits and coolants with the enthalpy-temperature curves of the hydrocarbon-rich mixture.    (EP975923-A1)      A new process liquefies a hydrocarbon-rich stream, especially containing natural gas. Heat is removed by indirect exchange with coolants, in a mixed coolant circuit cascade. The cascade circuit coolants, have at least three different compositions. The first circuit pre-cools, the second liquefies and the third sub-cools the stream being liquefied. The new feature is cold-induction compression (P3, L3, S3) of the vaporised and superheated coolant mixture.    USE -   To liquefy especially natural gas, producing this LNG by indirect heat exchange.    ADVANTAGE -   This new process has a reduced specific energy consumption in comparison with prior art. For the same duty, the plant is both smaller and costs less. The use of cold-induction compressor sections means that the coolant vapour does not have to be heated to ambient temperature before compression, increasing efficiency. This also cuts down the heat exchange area required; so smaller, lower cost exchangers can be specified. Functions of the interlaced cooling circuits are clarified in the text. An increase in thermodynamic efficiency results from optimal matching of the circuits and coolants with the enthalpy-temperature curves of the hydrocarbon-rich mixture.    (US6253574-B1)      A new process liquefies a hydrocarbon-rich stream, especially containing natural gas. Heat is removed by indirect exchange with coolants, in a mixed coolant circuit cascade. The cascade circuit coolants, have at least three different compositions. The first circuit pre-cools, the second liquefies and the third sub-cools the stream being liquefied. The new feature is cold-induction compression (P3, L3, S3) of the vaporised and superheated coolant mixture.    USE -   To liquefy especially natural gas, producing this LNG by indirect heat exchange.    ADVANTAGE -   This new process has a reduced specific energy consumption in comparison with prior art. For the same duty, the plant is both smaller and costs less. The use of cold-induction compressor sections means that the coolant vapour does not have to be heated to ambient temperature before compression, increasing efficiency. This also cuts down the heat exchange area required; so smaller, lower cost exchangers can be specified. Functions of the interlaced cooling circuits are clarified in the text. An increase in thermodynamic efficiency results from optimal matching of the circuits and coolants with the enthalpy-temperature curves of the hydrocarbon-rich mixture.