Analysis Of Population Composition And Nutrition Conditions For Excess Sludge Synthetic PHB

PHB (poly-β-hydroxybutyric acid) is an extracellular lactone, which produced by microbial fermentation. It can be used as a carbon source under the nutritional imbalance growth. It not only possesses the similar physical characteristics to the traditional chemical synthetic plastic but also has completely biodegradable characteristics. It can be widely applied in industry and life in future. During disposing the sewage, the remainder-sludge has plentiful mixed flora. By using these flora, it can produce PHB by certain domesticated to replace the traditional synthetic plastic. But the PHB’s production is low in terms of the ordinary domesticated technology. Therefore, this paper is mainly exploring the appropriate domesticate conditions to improve the PHB’s production, and analyzes its mixed flora diversity by PCR-DGGE technique.(1) By adjusting the activated sludge process in domestication, carbon, nitrogen and phosphorus ratio and domestication model, to improve the ability of active sludge production of PHB. Technology and application of PCR-DGGE to study microbial diversity of domesticated flora. In A/O alternate cycle SBR, we used sodium acetate as a substrate, gradually improve carbon source concentration and limit concentration of nitrogen source, artificial create nutrition disequilibrium to gradually improve the content of PHB within activated sludge. When carbon source gradually improve, COD rose to1200mg/L, the COD is1200mg/L and COD/N/P=1200/9.6/30, activated sludge in the accumulation of PHB maximum, reach64.2%of the dry weight of cells. In the process of domesticated sludge in the accumulation of PHB gradually increased, Sudan black, Albert staining and transmission electron microscopy images reveal gradually improve carbon concentration and limit the concentration of carbon which domestication way promote the active sludge accumulation PHB.(2) Adopting the PCR-DGGE technique and454High-throughput sequencing regularly analyze the flora diversity in the domesticated period. The results shows that, with the alteration percentage of the carbon, nitrogen, phosphorus, flora structure has undergone significant changes and the dominant bacteria gradually revealed in the mixed flora, with the formation of the high-yielding the PHB hybrid flora, flora structure tends to be stable. After DGGE flora dynamic analysis and electrophoretic bands on the recovery and sequencing of mixed flora, Acinetobacter, Bacillus, Bacteroides spp, Staphylococcus spp and Proteus was the dominant bacteria.