What is Leachate?
Leachate is the liquid that forms when water filters through waste in a landfill. It contains high concentrations of:
- Organic matter (COD: 500-50,000 mg/L)
- Ammonia nitrogen
- Heavy metals
- Chlorides
- Total Dissolved Solids (TDS: 1,000-30,000 mg/L)
Leachate Characteristics by Age
Leachate composition changes as landfill ages:
- Young landfill (<5 years): High organic acids, low ammonia, pH 4-6
- Medium age (5-10 years): Methanogenic, stable, pH 7-8
- Old landfill (>10 years): Low organics, high ammonia, pH 8-9
Leachate Treatment Technologies
1. Biological Treatment
Suitable for young leachate with high BOD/COD ratio. Methods include:
- Activated sludge
- Sequencing batch reactors (SBR)
- MBR (Membrane Bioreactor)
2. Physicochemical Treatment
For mature leachate with low BOD/COD:
- Coagulation-flocculation
- Advanced oxidation (Ozone, Fenton)
- Membrane processes (NF, RO)
3. Evaporation-Based Treatment
Asiatic Engineers' non-thermal evaporation system is ideal for:
- Concentrating leachate before discharge
- Achieving zero liquid discharge
- Handling high TDS and ammonia
- Reducing disposal volume by 90%+
Leachate Treatment in India - Challenges
- Regulatory pressure: CPCB guidelines strict on landfill Leachate
- Variable composition: Hard to standardize treatment
- Cost: Treatment can cost ₹200-500 per cubic meter
- Infrastructure: Many landfills lack proper collection/treatment
Case Study: Municipal Landfill Leachate (Gujarat)
Client: Municipal corporation in Gujarat
Problem: 100 m³/day leachate with TDS 15,000 mg/L
Solution: Asiatic Engineers Non-Thermal Evaporation System
Results:
- 95% volume reduction
- Recovered water for reuse in gardening
- ₹40 lakh annual savings vs tanker disposal
- GPCB compliance achieved
Conclusion
Leachate management is critical for India's waste sector. A combination of biological treatment for young leachate and evaporation for final concentration offers the most cost-effective solution.
Need leachate treatment solution? Contact Asiatic Engineers: +91 98240 54002