Understanding the limits of H2S degrading biotrickling filters using a differential biotrickling filter

The removal of H2S in high performance biotrickling filters was investigated using a differential biotrickling filter. The differential biotrickling filter was designed to reach high gas velocities through a minature packed bed, in this case a single 4-cm open-pore polyurethane foam cube. External mass transfer was limiting below air velocities of 3000–4000 m h−1, with possible other parameters such as biological kinetics or diffusion-controlled performance above 4000 m h−1. The effect of the liquid trickling rate on H2S elimination was found to be nil at low gas velocity, and significant at high gas velocity, consistent with speculations on the wetting of the packing and the rate-limiting step at the conditions of the experiments. The effect of additions of various species of sulfur on H S treatment was investigated. Sulfide negatively