Slotted tank

Highly indicative sizing of sludge and settling compartments of a slotted tank based on PE, flows, treatment type and temperature coefficient.

Slotted tank

This calculator provides a very rough sizing of a slotted tank – separately for the sludge (digestive) compartment and the settling compartment. It uses a specific volume per PE, a temperature correction factor and simple hydraulic criteria (surface overflow and retention times). Results are indicative only and must not be used as a detailed design.

Population equivalent [PE]

Average daily flow Q24 [m³/day]

Design maximum flow Qmax [m³/day]

WWTP type (for specific sludge volume)

Temperature coefficient kt [–]

The calculation is highly simplified. It ignores detailed hydrodynamics, tank geometry and sludge handling constraints. Always perform a detailed design according to applicable standards and guidelines.

Slotted tank design

Specific volume of sludge compartment [m³/PE]: 0.050

Sludge compartment volume without temperature correction [m³]: –

Sludge compartment volume with temperature correction [m³]: –

Settling area for Q24 (1.1 m³/m²/h) [m²]: –

Settling area for Qmax (2.0 m³/m²/h) [m²]: –

Design settling area [m²]: –

Sedimentation volume for 3 h at Q24 [m³]: –

Sedimentation volume for 0.5 h at Qmax [m³]: –

Design sedimentation volume [m³]: –

Retention time at Q24 [h]: –

Retention time at Qmax [h]: –

Total tank volume [m³]: –

Found an error? Let us know. Thank you.