Bioreactor Landfills
An Alternative to \"Dry Tombs\"
The bioreactor technology is gaining popularity in North America and Europe, and has been demonstrated at various landfills. A bioreactor landfill is a sanitary landfill that uses enhanced microbiological processes to transform and stabilize the decomposable organic waste within 5 to 10 years of implementation, compared to 30 to 100 years for \"dry\" Subtitle D landfills. Engineered bioreactor landfills (see Figure 1, below) can provide a more controlled means by which society can reduce the environmental impacts of landfills on the surrounding local environment.
Are you interested in the latest direction in EPA\'s Subtitle D program? We have prepared a summary.
Benefits
Engineered bioreactor landfills can provide the following economic and societal benefits:
- Accelerated waste biodegradation/stabilization.
- A means for recovery of capacity (air space).
- Minimized long-term environmental risk and liability.
- Reduction in post-closure care and maintenance.
- Decreased concentration of most leachate constituents as cycling of leachate removes or reduces contaminants.
- Reduction in the amount of leachate that the facility discharges to the local wastewater treatment plant, and subsequent discharge of effluent to the local environment.
- Affects gas yields to favor more economical utilization projects in the earlier years of the landfill life while reducing the greenhouse gas burden in the subsequent years.
- By extending the life of a landfill, it delays construction of new landfills.
Planning and Design
The planning and designing of a bioreactor landfill requires knowledge of the following:
- Landfill design and operation,
- Waste stream characteristics,
- Leachate quantity and quality,
- Leachate enhancement with nutrients, and
- Dynamics of waste degradation.
Legal issues, regulatory constraints, costs constraints, and public input may also influence planning and design. Because the system must function over the life of the landfill, SCS designs are flexible enough to be adapted to regulatory changes, technological advances, economic conditions, and variation in waste and leachate characteristics.
ZDROJ: www.scseng.com