| 摘要 |
Devices to remove polluting components from waste liquids are usually designed to operate satisfactorily as long as the input flow rate remains less than some maximum allowed value. Greater flow rates will cause inadequate purification and resulting downstream pollution, as well as possible damage to the device. An emergency overflow weir may be provided to divert excessive input flow into a buffer vessel or alternative discharge channel. The weir will divert a part of the excess flow, but the remainder will pass through the device; the relative portions depend on the relative flow resistance of the weir and of the device, respectively. The present invention enhances the flow resistance of the device when the flow rate through it is greater than the maximum allowed value, so that a greater fraction of the excess flow will be diverted by the emergency overflow weir. |
