藻类净水除杂系统对微塑料及氮、磷去除效果的影响

微塑料污染和养殖尾水超标排放已成为全球重要问题。在同一系统中，同时研究丝状藻对氮、磷的去除效果和对微塑料的拦截效果尚未见报道。为解决这一问题，本研究构建了一种藻类净水除杂系统，并研究其拦截微塑料和去除水体氮、磷的能力。研究使用水绵(Spirogyra)、浒苔(Enteromorpha)和刚毛藻(Cladophora)3种丝状藻在净水除杂系统中进行微塑料拦截实验，结果显示，实验时间为10 d时，3种丝状藻对纤维状微塑料拦截效果最佳(水绵88.50%，浒苔79.50%，刚毛藻75.50%)，对颗粒状微塑料拦截效果最差(水绵67.50%，浒苔53.00%，刚毛藻55.00%)。与其他2种藻类相比，水绵对微塑料具有更好的拦截效果，因此，使用水绵进行水体氮、磷去除实验。将单位面积的藻量分为0、2、4和6 g/dm²，在15 d的实验中，水绵对总氮的去除率最高为91.88%(4 g/dm²)，对总磷的去除率最高为90.33%(6 g/dm²)，对PO₄^3--P去除率最高为90.38%(6 ...

An algae water purification and decontamination system that removes microplastics, nitrogen and phosphorus

Microplastic pollution and excessive discharge of aquaculture tailwater have become important global issues. The use of filamentous algae to remove nitrogen, phosphorus, and microplastics in the same system has not been reported. In this study, we constructed an algal water purification and removal system and investigated its ability to remove microplastics, nitrogen, and phosphorus from the water column. Three kinds of filamentous algae were used, Spirogyra, Enteromorpha, and Cladophora, in microplastic removal experiments in the system; the three species of filamentous algae were the most effective in removing fibrous microplastics (88.50%, 79.50%, 75.50%) and the least effective in removing granular microplastics (67.50%, 53.00%, 55.00%), respectively. Spirogyra removed microplastics better than the other two algae; therefore, it was used for nitrogen and phosphorus removal experiments in the water column. The density of algae per unit area was set to 0 (control), 2, 4, and 6 g/dm2. Spirogyra showed a Total Nitrogen removal rate of 91.88% (4 g/dm2), a Total Phosphorus removal rate of 90.33% (6 g/dm2), and a PO43–-P removal rate of 90.38% (6 g/dm2) after 15 d. The density of 4 g/dm2 showed the highest removal rate, 90.38%. There were no significant differences between the experimental results of the 4 and 6 g/dm2 groups (P>0.05). The results showed that the system effectively removed fibrous microplastics and absorbed nitrogen and phosphorus from the water body and that an algal density per unit area of 4 g/dm2 was the most suitable for removing nitrogen and phosphorus in this system.