水网藻对不同粒径悬浮态镉的去除机制研究

Removal Mmechanism of Cadmium Suspended in Different Particle sizes by Hydrodictyon reticulatum

稻田系统对灌溉水中悬浮态镉的吸附是农田灌溉水中重金属净化的主要过程。从稻田结皮中采集水网藻,研究其对不同粒径高岭土载镉悬浊液的去除动力学过程,并结合重金属的分布形态分析,探讨结皮对不同粒径悬浮态镉的去除机制。结果显示:水网藻对离子态镉的富集作用强于胶体态镉,而对胶体态镉的富集量与胶体的粒径呈负相关。可见,进入水体中悬浮物与重金属结合后,能降低其被藻类俘获概率,增加其迁移能力,导致其污染距离增加。

The adsorption of suspended cadmium in irrigation water by paddy field system is the main process of purifying heavy metals in farmland irrigation water. The Hydrodictyon reticulatum was collected from paddy feld crust to study the process of removal of cadmium-loaded cadmium suspensions with different particle sizes. Combined with the analysis of the distribution of heavy metals, the removal mechanism of crusts with different sizes of suspended cadmium was investigated. The results showed that the accumulation of ionic cadmium was stronger than that of colloidal cadmium in Hydrodictyon reticulatum, while the concentration of colloidal cadmium was negatively correlated with the particle size of colloids. This experiment showed that the combination of suspended solids and heavy metals in the water body could reduce the probability of capture by algae, increased its migration ability, and increased its pollution distance.