Influence of filter media combinations on deodorization efficiency of bio‐trickling filters in swine facilities: A field study

Abstract Intensive pig farming produces significant malodorous emissions, posing a serious environmental challenge. Bio‐trickling filters (BTF) are commonly used for deodorization because they are cost‐effective, easy to operate, and maintain. However, the choice of filter media is crucial for BTF performance. This study systematically evaluated the effectiveness of three media combinations: sponge + plastic balls, plastic balls + Moving Bed Biofilm Reactor (MBBR), and MBBR alone. Then, their efficiency in removing NH 3 , volatile organic compounds (VOCs), and odor units (OU) from pig house emissions were further compared. Both the sponge + plastic balls and plastic balls + MBBR systems achieved the highest NH 3 removal rates. For VOCs treatment, the plastic balls + MBBR system initially removed 80% of VOCs, stabilizing at around 20%, indicating better performance stability compared to the sponge + plastic balls system. However, the MBBR system had a faster startup time of just 5 days due to its high specific surface area, while the plastic balls + MBBR system took 23 days to start up, likely due to limited surface roughness. Microbial analysis showed different dominant taxa: Firmicutes and Clostridium sensu stricto 1 were predominant in the sponge + plastic balls and plastic balls + MBBR systems, while Proteobacteria and Glutamicibacter were the core microbiota in the MBBR system, both crucial for pollutant degradation.