To change the sanitation scenario in India over the long-term, a systemic value-chain approach is needed. With this vision in mind, K. K. Nag has joined hands with DRDO to introduce sustainable measures such as the maintenance-free Bio-Digester Tanks. These can be installed across environments, are customisable and costeffective. They even use less water, which further strengthens their eco-friendly features and encourages adoption on a wide scale.
- Rotationally moulded, factory assembled, ready for installation
- Material of construction: Polyethylene
- Tank wall thickness: 7 mm (minimum)
- Heavy-duty poly-grass matting to ensure good formation of bacterial colonies
- 3 compartment design for complete digestion of faecal matter
- Lifting hooks for ease of handling
- Inbuilt vent pipe
| Sr. No. | Bio-Digester Tank Size – Litres | No of users in domestic setting | No of users in industrial setting | Tank Dimensions | First charge of AMI – Litres | |
| Dia (cms) | Height (cms) | |||||
| 1 | 700 | 4 to 6 | 8 to 12 | 1100 | 1015 | 200 |
| 2 | 1000 | 6 to 10 | 12 to 20 | 1100 | 1385 | 300 |
| 3 | 1500 | 10 to 20 | 20 to 40 | 1210 | 1670 | 450 |
| 4 | 2000 | 20 to 30 | 40 to 60 | 1425 | 1600 | 600 |
| 5 | 2400 | 30 to 35 | 60 to 70 | Two 700 litre tanks combined with one 1,000 litre tank | 700 | |
| 6 | 3000 | 35 to 45 | 70 to 90 | 1680 | 1665 | 900 |
| 7 | 3500 | 45 to 55 | 90 to 110 | Two 1,000 litre tanks combined with one 1,500 litre tank | 1000 | |
| 8 | 5000 | 55 to 80 | 110 to 160 | Two 1,500 litre tanks combined with one 2,000 litre tank | 1500 | |
| 9 | 7000 | 80 to 120 | 160 to 240 | Two 2,000 litre tanks combined with one 3,000 litre tank | 2100 | |
| Working Features | Septic Tank | Bio-Digester |
| Waste Degradation | Aerobic dominant | Anaerobic |
| Waste Decomposition | Only 30% | Up to 99% |
| Maintenance | Periodic removal of sludge, to be emptied every 2 years as per IS 2470 norms | Maintenance-free |
| Mechanical Sludge Removal | Pumping device required | No sludge removal required |
| Discharge from Tank | Odorous, sludge formation and hazardous waste | Odourless, colourless and hazard-free waste (water only) |
| Space for 300 Users | Three times more than the Bio-Digester, hence costly to construct and occupies more space | One third space required compared to Septic Tank, hence economical and has a smaller footprint |
| Sensitivity towards Cleaning Agents | Cannot tolerate toilet cleaning agents | Bacteria conditioned to remain unaffected by cleaning agents up to permitted limits |
| pH | 6.7-7.5 | 7.0-7.2 |
| Turbidity (NTU) | 500-800 | 70-90 |
| Total Suspended Solids (mg/L) | 150-300 | 90-120 |
| TDS (mg/L) | 500-850 | 350-450 |
| VS (mg/100ml) | 50-60 | 20-30 |
| COD (mg/L) | 1200-2000 | 250-300 |
| BOD 5 (mg/L) | 350-500 | 70-120 |
| Coliforms (MPN/ml) | > 3,000 | 300-350 |
