Rapid assessment of methanotrophic capacity of compost-based materials considering the effects of air-filled porosity, water content and dissolved organic carbon

• Key bulk parameters: air filled porosity, water content, dissolved organic carbon.
• Parameters are correlated with maximum CH4 removal rates in compost-based materials.
• A rapid assessment tool for performance estimation of filter media was developed.

Since the global warming potential of CH4 is 25 times that of CO2 on a 100-year time horizon, the development of methanotrophic applications for the conversion of CH4 to CO2 is emerging as an area of interest for researchers and practicing engineers. Compost exhibits most of the characteristics required for methanotroph growth media and has been used in several projects. This paper presents results from a study that was undertaken to assess the influence of physical and chemical characteristics of compost-based materials on the biological oxidation of CH4 when used in methane biofilters. The results showed that easily-measurable parameters, such as air filled porosity, water content and dissolved organic carbon, are correlated with maximum CH4 removal rates. The results obtained were used to develop an empirical relationship that could be regarded as a rapid assessment tool for the estimation of the performance of compost-based materials in engineered methanotrophic applications.