Numerical simulation of ozone concentration profile and flow characteristics in paddy bulks

Ozone has shown the potential to control stored product insect pests. The high reactivity of ozone leads to special problems when it passes though an organic medium such as stored grains. Thus, there is a need for a simulation study to understand the concentration profile and flow characteristics of ozone in stored paddy bulks as a function of time.

Simulation of ozone concentration through the paddy grain bulks was explained by applying the principle of the law of conservation along with a continuity equation. A higher ozone concentration value was observed at regions near the ozone diffuser whereas a lower concentration value was observed at regions away from the ozone diffuser. The relative error between the experimental and predicted ozone concentration values for the entire bin geometry was less than 42.8%.

The simulation model described a non-linear change of ozone concentration in stored paddy bulks. Results of this study provide a valuable source for estimating the parameters needed for effectively designing a storage bin for fumigation of paddy grains in a commercial scale continuous-flow ozone fumigation system. © 2017 Society of Chemical Industry.