A landfill which produces 200,000gpd of leachate needed a new treatment system to be able to discharge to surface water. Dynatec provided a Membrane Bioreactor (MBR) that utilized an existing tank as the bioreactor. A Reverse Osmosis (RO) system was also provided to further purify the MBR permeate prior to discharge. Repurposing existing assets saved the customer significant costs. The MBR conversion was the easiest and most cost-effective method to achieve their treatment goals.
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 system 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
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:
For more information on landfill leachate treatment systems, please contact Dynatec.
https://www.dynatecsystems.com/industries/landfill-leachate-treatment/