Hinkley Center Projects

Biodegradability Enhancement of Bioreactor Landfill Leachate with Fenton Processes

Florida is one of the forefront pioneers in moving the concept of Bioreactor Landfills (BL) from the research laboratories to the field management of landfills in Florida. The Hinkley Center provided critical support in the past two decades and nurtured the successful story of BL at the New River Regional Landfill (NRRL), in Union County, Florida. Recently, the innovative design of BL developed in Florida brought world recognition through the World Bank. However, as a landfill matures and is older than 10 years, biodegradability of the leachate will decrease significantly as the BOD/COD ratio of leachate decreases less than 0.10. As a result, BL will become less and less effective for mature landfills. For new landfills, extremely high concentration of COD is the major problem. For example, in Miami-Dade County, leachate causes the reclaiming wastewater cost as high as $9 per gallon in 1 GDM pilot scale water reuse plant. For the proposed 40 MGD full scale water reuse plant, the unit cost will be still as high as $2 per gallon due to mixing of leachate with its domestic wastewater. To reduce the cost, Fenton treatment of leachate before it is mixed with the domestic wastewater will offer a great solution to the challenging problem.

Fenton process refers to the generation of powerful oxidation species such as hydroxyl radical by using hydrogen peroxide and iron salts. Since the first report of leachate treatment using Fenton process by Huang, Dong and Tang (1993), Fenton process is proved to be an economic, non-toxic, simple and flexible oxidation process by hundreds of research papers in the past eighteen years. In this project, Fenton oxidation of leachate will be investigated as pre-treatment to increase biodegradability of leachate for BL. Optimal conditions of Fenton process will be determined in terms of H2O2/Fe2+ and H2O2/MSW(ton) to achieve the best biodegradability in terms of BOD5/COD ratio for both off-site and in-situ Fenton process.

The project will answer the following questions:

  • What is the relationship between COD removal efficiency (η) and COD loading (L) for different leachate at different H2O2/Fe2+ ratios.
  • How would the change of pH and H2O2/Fe2+ ratios affect the relationship between η and L?
  • Is it possible to use this relationship to design Fenton process without costly experiments?

Project Documents