Allows for dimensioning based on Chemical Oxygen Demand (COD) instead of just BOD . The Secondary Settling Tank (SST):
A 131 is unique in combining biological tank design with settling tank hydraulics. Appendix A (informative) includes settling tests (White method). The PDF must include Annex A in full – many illegal copies omit it. atv dvwk a 131 epdf top
Where ( F_COD ) is a factor for readily degradable COD (typically 0.5–2.0). Allows for dimensioning based on Chemical Oxygen Demand
The keyword phrase reveals user intent:
Where:
The guideline provides a deterministic mathematical methodology to dimension single-stage activated sludge systems. Unlike purely empirical approximations, this standard systematically links sludge age, operational temperature, organic loading, and specific nutrient removal requirements. Key design targets covered by the standard include: Atv DVWK A 131 e | PDF - Scribd The PDF must include Annex A in full
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