A field scale trial was undertaken at a landfill site in Sydney, Australia (2004-2008), to investigate passive drainage and biofiltration of landfill gas as a means of managing landfill gas emissions from low to moderate gas generation landfill sites. The objective of the trial was to evaluate the effectiveness of a passive landfill gas drainage and biofiltration system at treating landfill gas under field conditions, and to identify and evaluate the factors that affect the behaviour and performance of the system. The trial results showed that passively aerated biofilters operating in a temperate climate can effectively oxidise methane in landfill gas, and demonstrated that maximum methane oxidisation efficiencies greater than 90% and average oxidation efficiencies greater than 50% were achieved over the 4 years of operation. Thus, landfill gas loading was the primary factor that detected the behaviour and performance of the passively aerated biofilters. The landfill gas loading rate was found to control the diffusion of atmosphere oxygen into the biofilter media, limiting the microbial methane oxidising process. The temperature and moisture conditions within the biofilter were found to be affected by local climatic conditions and were also found to affect the behaviour and performance of the biofilter, but to a lesser degree than the landfill gas loading.
Authors: Dever Stuart A., Swarbrick Gareth E., Stuetz Richard M. ;Full Source: Waste Management (Oxford, United Kingdom) 2011, 31(5), 1029-1048 (Eng) ;