火山石生物滤床对微囊藻毒素的去除

Removal of microcystins by a vesuvianite nature-aeration biofilter

微囊藻水华爆发导致大量微囊藻毒素释放至地表水环境中,严重威胁着饮用水供水安全。通过不同条件火山石自然曝气生物滤床(活性挂膜、灭活挂膜、未挂膜和无填料滤床)对不同形态、构型(MC-LR、MC-RR)的微囊藻毒素的去除实验,探讨其去除效率、途径和机理。结果表明,火山石自然曝气生物滤床对微囊藻毒素的去除是微生物降解和基质吸附共同作用的结果。胞外毒素和胞内毒素的总去除率分别为58%和91%。其中,胞外毒素主要通过微生物降解作用途径去除,占胞外毒素总去除率的(41±4.2)%,胞内毒素则主要通过基质吸附途径去除,占胞内毒素总去除率的(64±5.1)%。生物膜吸附、光降解等其他途径无明显作用。另外,不同构型的微囊藻毒素在火山石自然曝气生物滤床中均能有效去除,MC-LR和MC-RR的去除率分别为68%和54%。

A large amount of microcystins are released to surface water due to the growing algae bloom,which seriously threaten the safety of drinking water. The removal efficiency,mechanisms and pathway of microcystins were studied by setting four different reactors of vesuvianite nature-aeration biofilter including active biofilm,inactive biofilm,no biofilm and no substrate reactor. The results showed that the removal of microcystin in vesuvianite nature-aeration biofilter was the joint action of microbial degradation and substrate adsorption. The average removals of extracellular microcystins and intracellular microcystins were 58% and 91%,respectively,and extracellular microcystin was removed mainly via microbial degradation( 41 ± 4. 2) %,while intracellular microcystin was removed mainly via sediment adsorption( 64 ± 5. 1) %. Boifilm adsorption,photodegradation,or other processes had no significant removal effect. Microcystins with different configurations can be removed synchronously with the vesuvianite natural biological aerated filter,the average removal efficiencies of MC-LR and MC-RR are 68% and 54%,respectively.