As per literature, SRT is estimated according to the equation
SRT = Xr*Vr*tc / (Xw*Vw+ Xe*Ve)
Xr=VSS content in the reactor (mg/L), Vr= working volume of the reactor (L), tc = cycle length (d), Xw= VSS content in the sludge wasted (mg/L), Vw= volume of sludge wasted (L), Xe = VSS content in effluent discharged (mg/L), Ve volume of effluent wasted.
There is no settling phase, Ve=0. The Vw amount of mixed sludge is removed at the end of cycle without any settling phase. Would the SRT change or remain the same.? What would be the SRT of the SBR?. Can we consider SRT=HRT?
Dear Jaya,
Your SRT equation for this strange SBR without effluent discharge (Ve=0) is incomplete as it does not include the influent volume Vi and its VSS content Xi.
If Vi=0 then the SBR reactor volume Vr would drop with each MLSS wasting Vw and the SRT would drop as well.
Without influent feed and effluent discharge, HRT would be HRT= Vr.tc/Vw.
Finally without settling: Xw = Xr.
I'm sorry but you need to review your SBR (no influent feed? no effluent discharge?) and its SRT equation.
Regards,
Bruno
The equation for HRT and SRT matches if you don’t consider the settling period. That means the solid is with the water solution for the whole period. So the time for hydrolic retention is actually the same time for solid retention.
Your SRT will = HRT, but this is not an SBR as you have no sequencing. This is just an aeration tank. The whole point of SBR is that you perform aeration, settling and denitrification in the same tank, removing the necessity for secondary clarifiers. Not sure what you are trying to achieve here?
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Inorganic Materials
- Metals
- Alloys
- Steel