飲用水處理程序二階段添加PAC與污泥毯穩定度提昇之研究

Enhanced Sludge Blanket Stability Using Two-Stage Dosage of PAC in Drinking Water Treatment Processes

李坤峰(Kun-Feng Lee)

指導教授 ： 莊瑞鑫

元智大學/工程學院/化學工程與材料科學學系/碩士(2001年)

摘要

科技發達的今日，水質日趨惡化，提昇淨水場淨水處理能力及改善其操作方式已是當務之急。本研究是針對淨水廠使用之高速膠凝沈澱池淨水設備，對污泥毯穩定度及操控性作探討，並於研究中建立一套模廠實驗裝置用以探討、分析比較一階段加藥程序與二階段加藥程序污泥毯之穩定性。
研究結果顯示採用二階段加藥程序可大幅增加其膠羽反應時間，其污泥毯比一階段加藥程序更為穩定。一階段加藥程序，淨水廠會因原水變化而需對混凝池之PAC加藥量作改變，造成大的污泥毯擾動(主要為膠羽性質之改變)，進而加重了快濾池嚴重的負擔。使用二階段加藥程序，可發現污泥毯比較不會因為混凝池PAC加藥量改變而造成擾動，主要是在第一階段加藥時混凝去除大部份有機質，使在第二階段加藥後之膠羽較不易受流力淘淅。
另一結果又顯現出，二階段清水殘留總鋁比一階段清水殘留鋁鹽量少了許多，可減少因攝取過量鋁鹽而導致神經系統的疾病(老人痴呆症)。此外，腐植酸的存在可增加污泥毯吸附重金屬Cu(II)之效果，影響程度與腐植酸加入量愈多吸附Cu(II)效果愈佳。

關鍵字

混凝 ； 聚氯化鋁 ； 界達電位 ； 污泥毯 ； 飲用水

並列摘要

With the development of high technology, the water sources are deteriorated. The most important thing is to improve the efficiency and operation of purification engineering. This research was to investigate the stability and performance of sludge blanket in high-speed flocculation settlers for purification plant of drinking water. In the mean time, a set of experimental equipment of pilot plant was built-up for comparing and analyzing the stability of sludge blanket in the single-stage and two-stage coagulation sedimentation process.
It was shown that adopting the two-stage coagulation sedimentation process has increased remarkably the formation time of floc, and the sludge blanket was more stable than single-stage coagulation sedimentation process. When the single-stage coagulation sedimentation process was adopted, due to the variety of raw water quality, the purification plant of drinking water needs to reduce the PAC dosage in rapid mixing basin, and the result has caused the sludge blanket highly eddied, and also increased the heavy loading of rapid filters. On the other hand, the sludge blanket was not eddied easily in spite of the reduction of PAC dosage in rapid mixing basin when two-stage coagulation sedimentation process was adopted. The main reason is, most of non-dissolved organic materials was removed in the first-stage coagulation, and as a result, the floc was not carried over easily in the second-stage coagulation sedimentation process.
Another result has shown that, the total residual aluminum in two-stage coagulation sedimentation process was much less than the one in single-stage coagulation sedimentation process. Besides, the existence of humic acid would enhance the sorption of heavy metal Cu(II).

並列關鍵字

coagulataon ； PAC ； zeta potential ； sludge blanket ； drinking water

參考文獻

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