Recirculation Flow given Recirculation Ratio is the flow generated in recirculation tank collecting the primary treated effluent from a pretreatment component, considering recirculation ratio. And is denoted by Qr'. Recirculation Flow given Recirculation Ratio is usually measured using the Cubic Meter per Day for Volumetric Flow Rate. Note that the value of Recirculation Flow given Recirculation Ratio is always positive. Typically, the value of Recirculation Flow given Recirculation Ratio is greater than 0.