| Due to climate change and water eutrophication, the global spread of cyanobacteria bloom is threatening the ecosystem and human health, especially in rivers and reservoirs as drinking water source. In China, every year, the outbreak of cyanobacteria bloom has become one of the serious water pollution problems.Seasonal surface water microalgae increment caused by water color and odor problems more water treatment process challenges. The main difficulty lies in the water treatment facilities in the cell density increases and algae metabolic activity by cells secreted metabolites in the surrounding environment, and cell lysis caused by all kinds of factors lead to the release of intracellular substances, these substances in drinking water treatment process will produce disinfection by-products of increased adverse consequences are derived. Therefore, removal of the secondary metabolites of cyanobacteria cells and water has become a difficult task, and it is necessary to develop a new method to deal with the pollution of water bloom in drinking water source.In this paper first using peroxydisulfate oxidation of extracellular secretion of the three main model compounds, detected after treatment of model compounds degradation products with the oxidant cast with different doses, to deal with the effects of liquid in total organic carbon(TOC), 254 nm absorbance, zeta potential and fluorescence characteristics. It was found that the specific degradation of the proteins in the treatment of three kinds of model compounds was proved to be superior in the treatment of proteins. At the same time, it is found that the oxidation ability of the small molecules such as humic acid is limited, so that they can not be completely mineralized. Then we select the outbreak of cyanobacteria during the representative algal species of Microcystis aeruginosa, under the laboratory condition culture into pure algae culture medium to simulate the effect of algae bloom during high algae laden water processing. The different oxidant dosage under the verdigris Microcystis aeruginosa pure algae culture was treated with algal cells removal rate, zeta potential, algal cell intracellular substances leaking and water outlet concentration of iron ion indexes were detected. The results showed that the removal rate of Microcystis aeruginosa was the best when the oxidant dosage was 400 M/L, and the highest removal rate was 97.2%. And because of the best coagulation effect at this time, the activator dose not have too much influence on the iron ion content of water. At the same time, it also found that the excessive amount of oxidant can cause the rupture of algae cells, which provides a reference for the practical application.Furthermore, the treatment of Microcystis aeruginosa cells and supernatant functional groups in different oxidant adding dose changes were characterized and general functional groups before and after the change and different doses of oxidation agent treatment on Microcystis aeruginosa cell morphology change to elaborate a sulfate pre oxidation treatment of Microcystis aeruginosa mechanism. The results showed that the non covalent interactions of the proteins in the extracellular secretion of algae were changed due to the oxidation of the proteins in the extracellular secretion of algae. And by different doses of oxidant on Microcystis aeruginosa cell morphology from the smooth and full of spherical to the fuzzy boundary of cell membrane, eventually collapse to the maintenance of cell morphology and completely broken the experiment phenomenon is further proof that the right amount of oxidants can get algae removal, and the excess oxidant but will cause water quality is not satisfactory, the consequences of.It was proved in this paper, which can be regarded as can remove algae cells, as well as reduce algal cell rupture of a safe and effective method in the selection of an appropriate amount of oxidation agent investment plus the amount of case, persulfate as an advanced oxidation method. |
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