This study aimed to investigate the capacity of laboratorial scale aerated biofilters to oxidise methane. The method used four types of organic and mineral-organic materials were flushed with a mixture of CH4, CO2 and air (1:1:8 by volume) during a six month period. The filter bed materials were as follows: (1) municipal waste compost, (2) an organic horticultural substrate, (3) a composite of expanded perlite and compost amended with zeolite, and (4) the same mixture of perlite and compost amended with bentonite. Methanotrophic capacity during the six months of the experiment reached maximum values of between 889 and 1036 g m-2 d-1. Batch incubation tests were carried out in order to determine the influence of methane and oxygen concentrations, as well as the addition of sewage sludge, on methanotrophic activity. Michaelis constants K M for CH4 and O2 were 4.6-14.9%, and 0.7-12.3%, respectively. Maximum methanotrophic activities V max were between 1.3 and 11.6 cm3 g-1 d-1. The study demonstrated the activity significantly increased when sewage sludge was added. The authors concluded the type of filter bed material (differing significantly in organic matter content, water-holding capacity, or gas diffusion coefficient) was not an important factor in determining methanotrophic capacity when oxygen was supplied to the biofilter.
Authors: Pawlowska, Malgorzata; Rozej, Agnieszka; Stepniewski, Witold ;Full Source: Waste Management (Oxford, United Kingdom) 2011, 31(5), 903-913 (Eng) ;