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Hydraulic retention time
Calculate nominal residence time from working volume and flow.
Equation and assumptions
θ = V/Q
Nominal steady volumetric residence time. Excludes short-circuiting, dead zones, recycle and residence-time distributions; it is not effective disinfection contact time.
The source below supports the underlying unit, mass-balance or hydraulic method. It does not validate this software or a proposed engineering design.
U.S. EPA — wastewater process control manualUse for preliminary screening. Verify inputs, physical assumptions and results independently before engineering design, operational changes or safety decisions.
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