文档介绍：冷冻预处理对剩余污泥性质的影响研究
胡凯,赵庆良,邱微
(哈尔滨工业大学市政环境工程学院,黑龙江哈尔滨150090)
摘要:为了提高污泥的有机物溶出率,以利于后续生物处理,采用冻/融技术对城市污水厂的剩余污泥进行预处理,考查了冷冻时间对污泥理化特性的影响。结果表明,冻/融处理可以破解污泥,将固体物质转化为液相成分。随着冷冻时间的增加,污泥pH值下降,SCOD和碱度上升;冷冻污泥的SS和 VSS值与冷冻时间相关。粒径分布和微观结构观察也证实了污泥絮体已被破坏。与混合污泥(初沉污泥+剩余污泥)相比,剩余污泥粒径分布的变化更加显著。剩余污泥和混合污泥经过冻/融(72h/3h)处理后,有机物溶出效果较好,污泥的物理特性也得到了改变。
关键词:冷冻;污泥;粒径分布;絮体结构;污泥破解
Effect of Freeze/thaw Pre-treatment on Sewage Sludge Characterization
HU Kai, ZHAO Qing-liang, QIU Wei
(School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China)
Abstract: In order to solubilize anic matter, which facilitated subsequent treatment process, freeze/thaw process was adopted as a waste activated sludge pre-treatment. Effect of freezing time on sludge characteristics was investigated. Results showed that freeze/thaw treatment could achieve sludge disintegration by anic matter from solid phase into aqueous phase. Sludge pH decreased with an increasing freezing time, along with SCOD and alkalinity increment. Correlation analysis showed that SS and VSS were dependent of freezing time. Destruction of sludge floc was confirmed by particle size distribution and sludge microphotograph. A dramatic change regarding waste activated sludge in particle size distribution was observed in contrast with mixed sludge. Improvement of sludge solubilization and changes of physical properties were at