Modeling ozone deposition on bulk grains and ozone deposition in columns of wheat grains

To better understand ozone deposition on bulk grains to control bacterium and insects, we investigated time-dependent deposition of ozone at various depths in columns of grains. We proposed a model of ozone deposition on bulk grains based on a material balance for ozone. The model included porosity, pore shape factor and velocity of ozone gas for bulk grains. The model was applied to determine the time-dependent deposition velocities of ozone at various depths in columns of wheat grains. Ozone deposition on wheat grains had two distinct phases. Phase 1 was characterized by high deposition velocities and then rapid decrease. In phase 2, the deposition velocities were kept constant with the time at various depths in the column. The saturation time based on the deposition model was 87.1h and the relative error was 2.4% for grade 4 hard red winter wheat with a moisture content of 10.3% at 22.0 °C. The surface reaction probability was the order of magnitude of 1 × 10−6 in the saturation state. This deposition model can be applied to optimize the ozone treatment for various kinds of grains. •A model of ozone deposition on bulk grains based on a material balance was proposed.•Saturation time was evaluated by analyzing ozone deposition velocities for grade 4 HRW wheat.•Surface reaction probability was evaluated for HRW wheat.