含藻污泥脫水調理之研究

Abstract

本研究利用高分子聚合物對污泥進行脫水調理,並將探討含藻污泥在不同 高分子聚合物,不同攪拌能量下調理之水結構分佈及膠羽結構之變化,同時 亦探討污泥在老化過程中藻類及其衍生物所引起污泥基本特性之變化與其 對脫水調理之影響.研究中以膨脹計法進行含藻污泥調理之結合水分析,並 用碎形維度分析技術進行污泥結構變化之研究,發現陽離子性及適量之高 分子聚合物可降低結合水含量及明善顯改善脫水效率,但過量加藥時則造 成結合水含量增加及脫水效率之降低,經由碎形維度分析結果顯示, 污泥 之結合水含量增加乃因污泥顆粒膠羽粒徑變大及有效密度降低. Water reserviors, major sources of water supply in Taiwan, have been partiallypolluted and become eutrophic, thereby resulting in the existance of algae inwater treatment operation. In general, the algae in source water can be removed by the flocculation and sedimentation process and incorporated in the sludge.The sludge containing algae appears more complex structure and its behavior isclose to the mixture of chemical and biological sludge. The species and quantity of algae on or in the sludge affect the surface properties, electronic characteristics, and the distribution of moisture as well as he following conditioningand dewatering performance.Polymer conditioning is commonly applied to reduce the coast of dewatering byimproving the dewatering characteristics of sludge. We propose an approach to investigate the floc structure and moisture distribution of sludge under the different mixing intensity, duration and polymers types. However, there is stilla little informance about the influence of algae and their exudates on the sludge conditioning as well as dewatering.In this study, we have applied the dilatometer to measure the bound water content, and the fractal analysis to investigate the change of floc structure. The results find that the cationic polymer and optimal dose of polymer can effectively reduce the bound water content and significantly improve the dewaterability of sludge. However, the overdose of polymer cause an increase of bound water content and a reduction of dewaterability of sludge. It also indicates, through the fractal analysis, the increase of bound attributes tothe decrease of effective density as the sludge floc aggregates during the conditioning.