Its shortcomings include harsh restriction for suspended solid in influent, low phosphorus removal efficiency, high water-head loss and the heightoflifting sewage.
但同时也存在对进水悬浮物要求较高,磷去除率低,水头损失大,污水提升高度大等问题。
2
The study of more than 700 teachers found that lifting children, working at child-height computers and desks as well as standing all day was contributing to their ills.