Landfill leachate treatment system for a hazardous waste landfill incorporates heavy metals pretreatment followed by a tubular MBR system.
The MBR reduces:
- ammonia
- phenol
- Polychlorinated Biphenyl (PCB)
- chemical oxygen demand (COD)
- volatiles and semi-volatiles
- and other contaminants adequately for discharge
The system reduces PFAS 30-60% and carbon is utilized to reduce PFAS to low ppt concentrations.
Landfill leachate treatment systems with Membrane Bioreactors (MBR)s have developed many unique process improvements for industrial wastewater applications. Dynatec successfully uses Ultrafiltration (UF), MBR and Reverse Osmosis (RO) for landfill leachate applications.
Landfill leachate treatment requirements
Treatment can vary, depending on the discharge requirements, and the contaminants present
Landfill leachate is characterized by:
- High Total Dissolved Solids (TDS)
- Heavy metals
- High BOD
- Color
- High COD
- High ammonia
Landfill leachate treatment systems options
The MBR option: an aerated biological mixed liquor process operating at very high solids concentrations.
The advantages are:
- Long sludge age produces a well acclimated biomass. High concentration (typically 12,000 to 20,000 mg/l) provides very high rates of reaction
- Excellent nitrification and de-nitrification
- Smaller footprint then conventional aerated systems
- High-quality effluent as a result of using membranes for final clarification
- Lower sludge production than conventional systems
Typical MBR results in landfills:
| Parameter | BOD | COD | TSS | Ammonia |
|---|---|---|---|---|
| Influent | 500 | 4000 | 150 | 1000 |
| Effluent | <5 | 800 | <5 | <1 |
| % Removal | >99% | 80% | >96% | >99% |
The system produces bio-sludge, which can either be dewatered for disposal, or disposed of as a liquid sludge.
Alternative landfill leachate treatment options:
- Chemical precipitation of metals before MBR treatment
- RO after MBR treatment removes organic and inorganic contaminants, and color
- UF followed by RO
The two effluent streams from a RO system are:
- Permeate
- Concentrate (or reject)
This can be re-injected into the landfill. Its long-term effects on leachate concentrations should be considered.
Conclusion
The MBR process provides the highest possible levels of organic removal with essentially zero suspended solids in the effluent. This is the ideal feed system for RO treatment.
RO permeate can be used for other non-potable purposes:
- Irrigation
- Truck washing
- Dust control
Dynatec membrane treatment systems have successfully provided outstanding performance in many landfill leachate applications. Considerations for this technology include:
- Membrane treatment offers reliable, consistent landfill leachate
- Systems are highly cost effective, and require low levels of operator interface
- The best membrane system configuration for each application should be individually evaluated
- Membrane treatment is broadly applied in the US and abroad
https://www.dynatecsystems.com/industries/landfill-leachate-treatment/
For more information on landfill leachate treatment systems, please contact us today.