IS 13628:1993 is the Indian Standard (BIS) for sewage treatment plants - guidelines for selection of process. This standard provides comprehensive guidelines for selecting an appropriate process for sewage treatment plants. It outlines key factors like influent characteristics, desired effluent quality, land availability, and cost-effectiveness, while describing various common treatment systems to aid decision-making for engineers.
Offers guidelines for selecting appropriate sewage treatment processes based on various factors like influent characteristics, effluent quality requirements, and cost.
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Effluent BOD for Inland Surface Water Discharge | ≤ 20 mg/L | ≤ 25 mg/L (often stricter based on receiving water sensitivity) | EU Directive 91/271/EEC |
| Effluent TSS for Inland Surface Water Discharge | ≤ 30 mg/L | ≤ 35 mg/L (often stricter, e.g., 25 mg/L) | EU Directive 91/271/EEC |
| Effluent Total Nitrogen (TN) for Sensitive Areas | Not specified for general discharge (50 mg/L for irrigation) | ≤ 10 or 15 mg/L (annual mean) | EU Directive 91/271/EEC |
| Effluent Total Phosphorus (TP) for Sensitive Areas | Not specified | ≤ 1 or 2 mg/L (annual mean) | EU Directive 91/271/EEC |
| BOD Removal in Primary Sedimentation | 25-40% | 25-40% | EN 12255-4:2002 |
| F/M Ratio (Conventional Activated Sludge) | 0.2 - 0.4 kg BOD / kg MLSS.day | 0.05 - 0.15 kg BOD / kg MLSS.day (for low-loaded plants with nutrient removal) | DWA-A 131E:2016 |
| HRT in Primary Clarifier | 2.0 - 2.5 hours | 1.5 - 2.5 hours (at average dry weather flow) | EN 12255-4:2002 |