Methane-oxidizing microbial communities from a full-scale compost biofilter operating under thermophilic conditions for treatment of manure-derived methane emissions in Gilleleje, Denmark
This study investigates the microbial community composition of a full-scale compost biofilter installed to treat methane-rich manure gas from a pig production system in Denmark. The biofilter was originally designed and operated as described by Falk et al. (2026), where a 400 m² system consisting of a gas distribution layer and a compost-based oxidation layer was used to mitigate methane emissions from a tent-covered manure storage tank.  The system receives manure-derived gas collected from the headspace of the storage tank and transports it into the biofilter, where biological methane oxidation occurs under thermophilic conditions (~49–50°C). Previous work demonstrated high methane removal efficiencies and strong spatial variability in oxidation activity within the filter, with methane oxidation occurring both in the gas distribution layer and throughout the compost matrix.  In this study, we focus on characterizing the microbial communities within the compost biofilter to better understand the structure and composition of methane-oxidizing bacteria (MOB) and associated microbial populations responsible for methane mitigation under high-temperature field conditions. Samples were collected from different spatial locations within the biofilter, representing gradients in methane loading and oxidation activity.  The compost biofilter provides a thermophilic environment enriched in methane and oxygen, creating selective conditions for methane-oxidizing microorganisms. This work aims to link microbial community structure to previously observed functional performance, including high methane oxidation efficiency and spatial heterogeneity across the biofilter system.
This study investigates the microbial community composition of a full-scale compost biofilter installed to treat methane-rich manure gas from a pig production system in Denmark. The biofilter was originally designed and operated as described by Falk et al. (2026), where a 400 m² system consisting of a gas distribution layer and a compost-based oxidation layer was used to mitigate methane emissions from a tent-covered manure storage tank.  The system receives manure-derived gas collected from the headspace of the storage tank and transports it into the biofilter, where biological methane oxidation occurs under thermophilic conditions (~49–50°C). Previous work demonstrated high methane removal efficiencies and strong spatial variability in oxidation activity within the filter, with methane oxidation occurring both in the gas distribution layer and throughout the compost matrix.  In this study, we focus on characterizing the microbial communities within the compost biofilter to better understand the structure and composition of methane-oxidizing bacteria (MOB) and associated microbial populations responsible for methane mitigation under high-temperature field conditions. Samples were collected from different spatial locations within the biofilter, representing gradients in methane loading and oxidation activity.  The compost biofilter provides a thermophilic environment enriched in methane and oxygen, creating selective conditions for methane-oxidizing microorganisms. This work aims to link microbial community structure to previously observed functional performance, including high methane oxidation efficiency and spatial heterogeneity across the biofilter system.
Department of Environmental and Resource Engineering