Statewide (PA) Chlorine Contact Time Tracer Study - Gwin, Dobson ...

Baffling Condition T 10
/T Baffling Description Typical Unit Process
Unbaffled 0.1 None, agitated basins, very low length Clearwell, storage tank, no baffles or perforated inlet or
to width ratio, high inlet and outlet
outlet, submerged inlet and outlets.
flow velocities
Poor 0.3 Single or multiple unbaffled inlets and Conventional sedimentation
outlets, few to none intra basin baffles
basins or clearwell with
2 or 3 baffles
Average 0.5 Baffled inlet or outlet with some intra‐ Some sedimentation basins
basin baffles
with several baffles
Superior 0.7 Perforated inlet baffle, serpentine or Filters or clearwell with perforated intra‐basin baffles,
outlet serpentine baffling
weir or perforated launders
“Perfect” (plug flow) 1.0 Very high length‐to‐width ratio Piping (pipeline flow), perforated inlet, outlet
and intra‐basin baffles