START AND STOP METHOD OF RAW MATERIAL GAS LIQUEFACTION DEVICE, AND RAW MATERIAL GAS LIQUEFACTION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a start and stop method of a raw material gas liquefaction device, capable of starting and stopping a raw material gas liquefaction device while reducing load on a heat exchanger and axial vibration of an expansion turbine, and a raw material liquefaction device executing the start and stop method.SOLUTION: A raw material gas liquefaction device 101 causes a controller 150 to: flow refrigerant to an expansion turbine and a gas bearing unit and perform initial cooling of the expansion turbine; next supply refrigerant to the expansion turbine and perform initial start of the expansion turbine at an initial start rotational frequency; and then steeply increase the rotor shaft rotational frequency of the expansion turbine from the initial start rotational frequency up to a safe rotational frequency beyond a critical speed region.SELECTED DRAWING: Figure 2