Characterization Of Microcystis Aeruginosa Immobilized In Complex Of PVA And Sodium Alginate And Its Capacity On Phosphorous Removal As A Special Creature

The eutrophication has been one of the most serious environmental for decades. It has deleterious effects to the whole ecosystem. Both human’living and society’ continuous development are endangered. Based on ecological niche theory, the commonly seen algae in eutrophication reformed by immobilization technology was treated as a new kind of special species. Our findings are integrated to provide new insights into the issue of eutrophication.The first step of the issue in the immobilization of Microcystis Aeruginosa (MA) had been study. MA was inoculated and cultured in laboratory. According to the merits of immobilization technology, MA was immobilized in the complex of10%PVA (polyvinyl alcohol) and1%sodium alginate crosslinked by4%CaCl2. The harvested immobilized beads was cultured for15d. Durning the culture, the chlorophyll a in the immobilized beads and medium were measured as the symbol of whether the alage owning bioactivity. The results showed that not only the alage could grow, but also the method was effective in immobilizing algae, without leakage.The immobilized MA was treated as a new kind of special species, and its properties were investigated. Two groups of immobilized beads (cultured and uncultured) was setting as comparion. Results revealed that the gel beads have mechanical strength and chemical stability even under non-sterile harsh conditions, which might be attributed to the rarely seen structure (three different layers:dense surface, regular of tubular-shaped divergent structure and honeycomb crystal lattice layer) of the immobilized MA determined by SEM. SEM also displays more quantity of MA attached to the inwall after cultivation which demonstrates that the MA within beads maintained high bioactivity. The difference between cultured beads and incultured beads could be neglected. Considering the restriction of time in actural wastewater treatment, the incultured beads could be used for pretreatment.Both cultured and uncultured beads’capability on removal phosphorous in the presence and absence of the BG-11medium were examined in the third step. And the cultured beads’range of removal ratio was80.3%-77.7%, the uncultured beads was82.7%-76.3%respectively, which indicated that the beads without providing ample nutrients still had high capacity of P removal, and the cultured beads’ability on removal phosphorous was more stability. In addition, control experiment, utilizing PVA-SA beads without immobilized MA, demonstrated that MA within beads play key role in absorbing P. So it was concluded that the immobilized MA can be applied in actual eutrophication treatment systems. Chlorophyll a was used to characterize the bioactivity of the immobilized MA throughout this study.