单项选择题
A.saltwater heater shell
B.the condensation of the saltwater feed
C.air ejectors, eductors, or a separate vacuum pump
D.condensation of the distillate
单项选择题 In the two stage flash distilling plant, which of the pumps listed is vented to the shell of the second stage in order to remove vapor from the pump suction?（）
单项选择题 The purpose of an oil mist detector in a main propulsion diesel engine is to warn of （）
单项选择题 Permitting a diesel engine fuel oil day tank to run dry can cause （）