单项选择题
Which of the following is wrong about operation of oily water separator?（）
A.filled with clean water before operation B.keep air cushion in oil collecting space during running C.check oil level during running D.clean inner separator with low pressure stream
单项选择题 When oily water separator is operating, which measure （） is wrong.
单项选择题 The following measures can be used to improve oily water separator’s separating effect except （）
单项选择题 If separating effect is not good, which measure should be taken （）
