不同碳源类型对活性污泥PHA贮存及转化的影响

采用经乙酸钠驯化培养的具有吸放磷功能的活性污泥,考察了不同碳源类型对厌氧底物贮存和转化的影响,碳源包括乙酸/丙酸=1/2、乙酸/丙酸=2/1、丙酸、甲醇、乙醇、葡萄糖、淀粉及生活污水。试验结果表明,以乙酸和丙酸为碳源时,系统的底物贮存量较大,其中进水乙酸/丙酸=1/2条件下系统内PHA及PHB含量最多,为6.0mmolC.L-1及4.25mmolC.L-1,而乙酸/丙酸=2/1条件下PHV含量最多,为3.69mmolC.L-1。系统可以利用甲醇、乙醇、葡萄糖、淀粉及生活污水作为碳源物质进行底物贮存,贮存物以PHB为主,但贮存量较乙酸及丙酸低。以乙酸及丙酸为碳源时,磷的释放量随着丙酸含量的增加而升高,丙酸为单一碳源条件下,磷的释放量达到最大值,为16.53mg.L-1。以淀粉及生活污水为碳源时释磷量小,为3.56mg.L-1与6.75mg.L-1,而甲醇、乙醇及葡萄糖为碳源时考察的活性污泥没有表现明显的释磷特性。

Effect of various types of carbon source on biochemical storage and substrate transformation of activated sludge

It was investigated that the effect of type of carbon sources, including acetic acid/propionic acid=1/2, acetic acid/propionic acid=2/1, propionic acid, methanol, ethanol, glucose, starch and domestic wastewater, on anaerobic substrate storage and conversion of activated sludge domestricated cultured with sodium acetate with removing phosphorus.The results showed that with acetic and propionic acid as carbon source, the system’s storage capacity for substrate was larger, in which the maximum values of PHA, PHB and PHV was of the 6.0 mmolC·L^-1, 4.25 mmolC·L^-1 and 3.69 mmolC·L^-1(at acetic acid/propionic acid=2/1）,respectively.When methanol,ethanol, glucose,starch and domestic sewage were used as carbon source for substrate storage, the storaged substance was mainly PHB,but their capacity lower than that of acetic and propionic acid.The release of phosphorus increased with propionic acid content in combined acetic and propionic acid and reached the maximum 16.53 mg·L^-1 at propionic acid as sole carbon source.With starch and domestic sewage as a carbon source,the phosphorus release was small, 3.56 mg·L^-1 and 6.75 mg·L^-1, while methanol, ethanol and glucose as carbon source the activated sludge showed no significant phosphorus release features.