Test Of The Physical Morphology And Characterization Of The Parameters On Complex Biofilms

Biofilm wastewater processing is one of the main waste water treatment technology. Whether microorganisms in the reactor can effectively form biofilm is a key factor in biofilm wastewater processing. Biofilm composition, biofilm morphology and the spatial distribution of microorganisms in the reactor determine the effective biofilm formation, and to maintain stable operation.The variation of quantity, property, structure and morphology of the biofilm with the reactor operation parameters in two sets of biofilm reactor treating synthetic wastewater were studied in this thesis. The main contents include:(1) The experimental set-up of up-flow biofilm reactor (UFBR) used hanging flexible three-dimensional carrier is built, and the formation process of biofilm on the carrier is investigated under different influent concentration, hydraulic retention time and aeration.In addition, the variation of biofilm characteristics are investigated, and the biofilm suitable growing conditions are analyzed.(2) The experimental set-up of sequencing batch biofilm reactor (SBBR) is built. The biofilm growth situation is investigated with parallel operation of three reactors in different COD/N influent conditions. The process of biofilm growth, including the variation of quantity, property, chemical composition and moisture content. The growth rule of biofilm is analyzed. The change of nitrogen compounds concentration and the distribution of heterotrophic bacteria, denitrifying bacteria and denitrifying bacteria are mainly analyzed.(3) The structure of complex biofilm formed in sequencing batch biofilm reactor is observed by scanning electron microscope (SEM), the results show that the hole structure is found, and biofilm is mainly formed by sphere, ellipsoidal, lever microbial and exocellular polymer.(4) Variation regularity of biofilm quantity in sequencing batch biofilm reactor is fitted by Origin8 fitting software, and the fitting equations is got. The biofilm quantity is smallest and biological activity is highest, indicating that the mass transfer process is not limited in the biofilm when the influent COD/N is 10.