Ormeci B, Vesilind P A
Department of Civil and Environmental Engineering, Duke University, Durham, NC 27708, USA.
Water Sci Technol. 2002;46(10):269-75.
In this study, the effects of extracellular polymers on freeze-thaw conditioning of activated sludge are investigated. Various physical and chemical extraction methods including centrifugation, blending, heat, EDTA, EGTA, and NaOH extraction were used to remove extracellular material from sludge matrix. The improvements in freeze-thaw conditioning were evaluated by commonly used measures of sludge dewaterability. The results of this study indicate that removal of extracellular polymers using relatively gentle extraction methods before freeze-thaw conditioning improves the sludge dewaterability after the freeze-thaw. In addition to extracellular polymers, cations also play an important role in determining the freeze-thaw effectiveness on activated sludge. Best dewaterability is achieved when both extracellular polymers and cations are removed from activated sludge before freeze-thaw conditioning.
在本研究中，考察了胞外聚合物对活性污泥冻融调理的影响。采用了包括离心、混合、加热、乙二胺四乙酸（EDTA）、乙二醇双四乙酸（EGTA）和氢氧化钠提取在内的各种物理和化学提取方法，从污泥基质中去除胞外物质。通过常用的污泥脱水性能指标来评估冻融调理的改善情况。本研究结果表明，在冻融调理之前使用相对温和的提取方法去除胞外聚合物，可提高冻融后污泥的脱水性能。除了胞外聚合物外，阳离子在决定冻融对活性污泥的效果方面也起着重要作用。当在冻融调理之前从活性污泥中同时去除胞外聚合物和阳离子时，可实现最佳脱水性能。
