储粮熏蒸过程中磷化氢浓度的分布模型及验证研究

The Model and Validation of Phosphine Fumigation in Stored Grains in Silos

谷物在长期储存过程中会受到害虫的侵扰,通常需要使用诸如磷化氢等适量的熏蒸剂对仓储粮食进行熏蒸,从而杀死害虫,同时又要避免害虫产生耐药性和熏蒸剂的残留。本研究首先建立和验证了熏蒸剂(磷化氢)的对流扩散和吸附模型,并采用计算流体动力学方法对圆筒仓内谷物熏蒸过程中磷化氢质量浓度进行了数值预测,分析了熏蒸过程中磷化氢的质量浓度分布规律,得出熏蒸过程中磷化氢质量浓度分布是不均匀的,并且受到谷物吸附和不可逆化学反应的双重影响。

Grains should be stored free from insect pests. Insects that infest stored grains in all life stages may be killed by being fumigated with poisonous gases as phosphine. In the paper, a mathematical model for convective diffusion and sorption of fumigants to be used in stored grains has been developed to be implemented by Computation- al Fuid Dynamics （CFD）. The model has been compared with published results and found to have excellent result. It is shown that the fumigation is non - uniform and the spatial distribution of fumigant can be affected by grain kernels adsorption as well as the non- reversible chemical reaction.