12 December 2014
Posted in Center Information
Principal Investigator: Dr. Gang Chen
Recirculating leachate appears to be one of the least expensive methods for partial treatment and disposal of landfill leachate at properly designed and operated landfill sites. The leachate recirculation not only improves the leachate quality, but also shortens the time required for landfill stabilization. In addition, aerated leachate recirculation may bring air into the landfill, leading to aerobic degradation of organic compounds and precipitation of heavy metals. Aerated recirculation also promotes nitrification, which makes it possible to remove nitrogen through denitrification after oxygen is consumed at the bottom part of the landfill. Although aerated leachate recirculation has these advantages, leachate is only partially treated. The leachate must be further treated in order to meet the discharge requirements. In this research, aerated recirculation and pressurized suspended fiber biofiltration were tested for the treatment of leachate from landfills in Northwest Florida. The pressurized suspended fiber biofilter was configured to allow biological contact oxidation, a novel and efficient treatment process for enhanced organic and iron removal. In between aerated leachate recirculation and pressurized suspended fiber biofiltration, ammonium and chloride in the leachate were removed through denitrification and the ultra-high lime with aluminum process. From this research, the best operation parameters were identified for leachate recirculation, denitrification, the ultra-high lime with aluminum process, and pressurized suspended fiber biofiltration operations. Cost and space saving were analyzed and compared with that of the conventional aerobic activated sludge systems.