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Algae problem in the treatment of drinking water has become highly valued as a growing problem in recent years, water eutrophication, the normal operation of the waterworks lake water as a water source by algae threat, the filter is clogged, recoil time shortened, raising the cost of water. The coagulation method as the most commonly used in water treatment processes, has been attracted much attention, especially in recent years, the development and utilization of composite coagulant bring a brighter future for Coagulation algaecide. Magnetic nanoparticles is added in the form of a magnetic fluid made of magnetic composite coagulant (MPFC) polymerization of ferric chloride (PFC), and for the removal of Microcystis aeruginosa. Magnetic nanoparticles, PFC and MPFC the physical and chemical properties, structural and morphological characterization (TEM, XRD, pHPZC, FT-IR and species distribution). Compare the different initial pH, coagulant dosage and ionic strength, PFC and MPFC Microcystis aeruginosa coagulation behavior. Magnetic nanoparticles join floc settling velocity, the presence of natural organic matter (NOM) the coagulation effect under the conditions and the removal of microcystins (MCs), and its mechanism of action . Seen through coagulant various characterization, synthetic magnetic particles are spinel structure Fe304 nanoparticles with PFC composite, its structure and morphology did not change, but changes the distribution pattern of the solution of Fe so that the early oligomers Fe decreased polymer increased. Compared with the PFC coagulant dosage exceeds a certain value, MPFC showed a synergistic effect of coagulation algaecide affected by pH, coagulant dosage and ionic strength of the influence of the small scope of widened. The initial pH value of 10, the dosage to 2mg / L (Fe), MPFC achieved 100% removal efficiency. Floc settlement power experiments showed that the addition of magnetic nanoparticles floc settling velocity significantly increase the. To better describe the characteristics of settlement floc settlement-powered semi-empirical equation, the diffusion constant k and the smaller the value of the reaction order n, sedimentation rate, the better. The presence of NOM will lead to increased coagulant dosage, MPFC maximum removal efficiency can be made better, and an increase in the removal efficiency of NOM, reduce the trend of the organic matter in water to form disinfection byproducts. Removal of MCs effect seen, MPFC can effectively alleviate the harm brought about by the release of intracellular microcystin in the coagulation process. The coagulation mechanism discussion suggests that the PFC and magnetic fluid suspension algaecide are electricity and adsorption mechanism, while the MPFC the coagulation is a result of the interaction of the magnetic nanoparticles and PFC. The magnetic nano-particles can be adsorbed algal cells, NOM, MCs and other negatively charged substances to the surface, and Fe in the polymer and the volume of the ferric hydroxide precipitate sweep net to catch under the action of the formation of large flocs are removed from the water sedimentation.
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