EVALUATION OF LEACHATE TREATMENT SYSTEM AT NAM SON LANDFILL - HANOI CITY

Abstract

In the foreseeable future, landfill will continue to be the primary means for MSW disposal in Vietnam. Due to its highly pollutive nature, the treatment of landfill leachate is particularly critical in landfill management. At Nam Son MSW landfill of Hanoi city (Vietnam), the presence of refractory organic substance, nitrogen compounds and other pollutants in the leachate has rendered the treatment processes ineffective. Since operation of Nam Son landfill in 1999, three leachate treatment systems have been practiced. One replaced another because oftheir inability in the reduction ofpollutants in the leachate to the standard permits, and owing to technical problems. To investigate what has happened, this study focuses on an evaluation of the problems pertaining to these treatment processes. In addition, leachate treatment at the Lorong Halus landfill in Singapore is also examined to allow a comparison in the leachtate composition and its treatability between the two landfills, located at different places in the same region. Analyses ofthe problems and weaknesses show that to be successful in the treatment of landfill leachate, a close examination of leachate flow, leachate composition, and the variability in its compositions on a long-term basis are needed. Understanding a treatment process is essential not only in facing with technical issues but also support to improve treatment efficiency. For the treatment of landfill leachate, a combined treatment is recommended. As leachate composition varies temporally and spatially, an adopted treatment technology should reflect these changes.