Author(s): Huiming Zhao; Yuefeng Zhang; Liqun Tang; Chonghao Wang; Xiaowei Gao; Yuhai Wang; Badin Liu; Chuansheng Guo; Haochuan Feng
Keywords: Bio-flocculation sediment; Micro architecture; Biofilm
Abstract: Sediment flocculation is very important for cohesive sediment dynamics. The bioflocculation of sediment induced by biological activity has attracted more and more attention over the last decades. In order to accurately understand the formation mechanism and structural characteristics of bioflocculation sediment, firstly, the micro-morphology of bioflocculation sediment in water environment should be visualized and its flocculating structure should be analyzed, so as to lay a foundation for further related research. Bioflocculation sediment has a small particle size in the order of micron, and there is organic matter-biofilms on the surface and between the particles. Therefore, the characteristics of sediment, microorganisms and their metabolites should be taken into account. Appropriate instruments and equipment should be used to observe bioflocculation sediment in situ, which couldn’t be dried, carbon plated, etc. In this paper, the flocculation structure of bioflocculation sediment was observed by means of environmental scanning electron microscopy and confocal laser scanning microscopy. A more intuitive understanding of its internal micro-environment and external behavior characteristics was obtained, and the great role of microbial activities and their metabolites in the structure and adhesion characteristics of bioflocculation sediment was revealed.