| 摘要 |
PURPOSE:To minimize turbulence applied to gas supplied from a cold-heat-utilizing power plant of the type in which LNG is expanded directly, by raising the pressure of gas at the inlet of a turbine to a required pressure in a short while by closing a turbine by-pass valve gradually in a forced manner. CONSTITUTION:In case of raising pressure during low-pressure vaporizing operation, a pressure control valve 21 is fully opened and an ON-OFF valve 16 is closed completely. Further, a set pressure value of an automatic controller 22 is set at the value equal to the measured value of gas pressure in a by-pass line 20, and then the automatic controller 22 is switched to ''automatic''. Resultantly, gas supplied from a vaporizer 1 is carried to a power plant boiler 14 via the pressure control valve 21 and an after-heater 19. Subsequently, a booster pump 4 is set into operation, and a flow control valve 9 on the high-pressure side is opened gradually by way of program control while a flow control valve 5 on the low-pressure side is closed in response to the signal given from a feed pressure control system 13. At the same time, the gas pressure at the inlet of a turbine 18 is raised by raising the set pressure value of the automatic controller 22 to a prescribed value by way of program-control. |
