Civil Engineering Reference
In-Depth Information
Level Control
Header Channel
Backwash Pipe
Motor Actuated Valve
Filter Bed
Underdrain
M
Constant Rate Filtration
(Constant Level Influent Flow Splitting)
Header Channel
HWL
LWL
Weir Box
Filter Bed
Underdrain
Control Weir
Backwash Pipe
Constant Rate Filtration
(Varying Level Influent Flow Splitting)
HWL
LWL
Header Channel
or Pipe
Filter Bed
Underdrain
Rate-of-Flow Controller
Backwash Pipe
Constant Rate Filtration
(Rate-of-Flow Controlled)
HWL
LWL
Header Channel
or Pipe
Weir Box
Filter Bed
Underdrain
Control Weir
Backwash Pipe
Flow Restriction
Declining Rate Filtration
Fig. 12-11.
Potential options for operating gravity filters
