Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/4956
標題: 改變快濾池濾料配置對淨水水質之影響
Effects on water quality by media modification of rapid sand filtration
作者: 賴重榮
Lai, Chong-Rong
關鍵字: rapid sand filtration;快濾池
出版社: 環境工程學系所
引用: 中文部分 圖書 水及廢水處理理論與實務─原著Ronald L.Droste. 石濤 (2006) 環境微生物學,鼎茂圖書出版股份有限公司,台北。 自來水設施操作維護手冊─自來水協會 徐振盛及李孟諺 (1995) 環境微生物學,淑馨出版社,台北。 高肇藩 (1990) 給水工程-自來水工程,三民書局股份有限公司,台北。 高肇藩 (1997) 給水工程,三民書局股份有限公司,台北。 黃政賢 (1997) 給水工程,高力圖書有限公司,台北。 期刊論文 洪瑋濃、林韶凱、劉育晰、邱宜亭、蔡沁芳(2011)水公司各淨水場清、配水含鋁量分析調查及最適化處理之研究,台灣自來水公司委託計畫。 郭譯惇(2009)探討截留於快濾池中微生物組成及其對過濾系統造成之可能影響,碩士學位論文─國立中興大學環境工程學系。 陳是瑩及曾怡禎 (1980) 鳳山水庫藻類與水質的季節性變化,藻類與環境研討會論文集: 75-83。 陳是瑩及曾怡禎 (1984) 澄清湖生態的研究 I:程清湖水質與藻類季節性變遷的研究,中華民國自來水協會第一屆給水技術研討會論文集。 曾怡禎、葉宣顯、賴文亮、陳振正、謝東穎、昇衡、蔡木川及王上銘 (1999) 不同淨水程序對藻類去除效率之研究,中華民國自來水協會第十六屆自來水研究發表會論文集: 121-130。 葉宣顯 (1999) 澄清湖高級淨水處理模場試驗研究(第一年)報告,台灣省自來水公司委託計畫。 葉宣顯、林財富、黃文鑑 (2011) 水庫底層水中有機物及臭味物質應急處理技術研究成果,台灣自來水公司委託計畫。 網路資源 行政院環保署環境檢驗所 (2005) 水中總菌落數檢測方法。 URL http://www.niea.gov.tw/ 行政院環境保護署 (2009) 90~96年度河川及水庫水質分析報告。 URL http://www.epa.gov.tw/FileDownload/FileHandler.ashx?FLID=9446 西文部分 Books FILTER ASSESSMENT MANUAL. South Carolina Department Health and Environmental Control. Third Edition, December 2003 FILTER TROUBLESHOOTING AND DESIGN HANDBOOK. AWWA. First Edition 2005. Maier, R.M., Pepper, I.L., and Gerba, C.P. (2000) Environmental Microbiology San Diego: Academic Press Journal Articles Arora, H., Giovanni, G.D., and Lechevallier, M. (2001) Spent Filter Backwash Water Contaminants and Treatment Strategies. Journal of American Water Works Association 93: 100-112. Incorporation filter bed expansion measurements into your backwashing routine. by Kevin Anderson& ED Chescattie Jekel,M.R.and Heinzmann, B., (1989)“Residual aluminum in drinking-water treatment”Journal of water Supply:Research and Technology-Aqua,38:281-288 J.L.Cleasby,(1990),”Filtration”in Water Quality and Treatment,4th ed.,F.W.Pontius,ed., McGraw-Hill,Toronto,reproduced with permission of McGraw-Hill,Inc . Letterman, R.D.and Driscoll, C T., (1988)”Survey of residual aluminum in filtered water”,Journal of American Water Works Association, 80(4),154-158. Mouchet, B. (1998) Solving Algae Problems: French Expertise and World-Wide Applications. Journal of water supply: research and technology- AQUA 47: 125-141. Naghavi, B.and Malone, R. (1986) Algae Removal by Fine Sand/Silt Filtration. Water Research 20: 377-383. Norton, C.D.and LeChevallier, M.W. (2000) A Pilot Study of Bacteriological Population Changes through Potable Water Treatment and Distribution. Applied and Environmental Microbiology 66: 268-276. Using Baseline Monitoring Techniques to Assess Filter Run Performance and Predict Filter Breakthrough. Michael J.Sadar.Application Scientist Hach Company Loveland Colorado.2000. Van Benschoten,J.E.and Edzwald,J.K., (1990)”Measuring aluminum during water treatment:methodology and application”,Journal of Japan Water Works Association,82(3),84-91
摘要: 
在傳統淨水程序中,過濾池是淨水處理去除懸浮固體物之基本系統。而過濾池之濾層主要是由濾料構成,為過濾處理之主要部分;若由比重相同之單濾料顆粒混合組成,反沖洗後粗濾料下降較快聚集在濾料下層,細濾料則累積在上部,過濾時大部分膠羽會在表層除去,水頭損失亦在表層快速增加,導致未能完全利用濾層內部之阻留容量。雖然細濾料在上可得到較佳之水質,但水頭損失大,濾程縮短為其缺點,若粗濾料在上可讓膠羽貫入較深有效利用容量,增加濾程容易反沖洗,但全部為粗濾料則有濁度貫穿濾層之可能,若濾料粒徑及孔隙能依水流方向逐漸減小則具有大量之除濁能力及高度之阻留機能。
因此,為進一步瞭解快濾池中之濾料組成對淨水程序產生之可能影響,本研究將針對現場雙濾料過濾池,及模擬濾床之單濾料過濾池,在相同過濾水源及不同濾率下,依「濾水池評估手冊」分別探討反沖洗前、後濾料差異;並在不同過濾時間點分別採取過濾水,利用比色法進行錳含量、鋁含量技術分析;藉由現場及模擬濾床之濾料、過濾水質進行比對,建構出不同濾料組成之過濾池,在一濾程中過濾水水頭、水質之變化差異。
在濾料分析結果,過濾30小時後,經採樣分析現場雙濾料過濾池(上層0.9mm濾煤40公分,下層0.45mm濾砂30公分,L/D=1100),主要膠羽顆粒在上層,模場單濾料過濾池(0.9mm濾砂90公分,L/D=1000),主要膠羽顆粒在中層,而模場濾料微生物分佈以上、中層為主。其次以相同反沖洗流速(21m/d)沖洗發現,模場單濾料過濾池因反沖洗流速不足,故濾料膨脹率過低僅5.5%,造成濾料沖洗不乾淨。
在過濾水質分析結果,經採樣分析發現,在過濾初期(<2-4hrs)及後期(>24hrs)濁度顆粒、顆粒性錳、鋁有穿透現象,濾速增加時更為明顯。不論濾速快或慢,整體上雙濾料對顆粒截留效果較單濾料為佳,當濾速為160m/d時雙濾料與單濾料去除效率差約10%。當濾速達230m/d時去除效率最大差可達50%。
在過濾水頭分析結果,濾水頭上升速度雙濾料明顯大於單濾料,最終兩者差達4倍,當濾速達230m/d時,現場雙濾料濾床濾程約24小時內,即可達滿水頭高度。
整體上在低濾率(<160m/d)操作下,目前現場使用雙濾料配置濾床,與改變單濾料配置後模場濾床,對淨水後水質差異不大(<10%);但在高濾率(>200m/d)操作下,單濾料配置模場濾床,對淨水水質處理效果較差(集中在初濾階段),但因穿透至過濾水之錳或鋁有50%以上屬溶解性,與濾料配置較無相關性,與使用氧化劑及水中pH值較有相關性。
濾程終了單濾料配置濾床濾水頭高度僅雙濾料配置濾床之1/4;因現場過濾池設備有18池,因此可分池、分階段更換濾料以提升處理水量,並持續監控過濾水質變化。另更換濾料前應一併檢討目前反沖洗設備,增加反沖洗流速至30m/h以上,以因應更換濾料後濾床之反沖洗。

Filtration is the primary suspended solids removal unit in traditional water purification process. Filter medium selection directly contributes to the efficiency of filtration. When different filter media with the same specific gravity are applied, coarse media will settle faster and locate in the buttom part of filtration unit after back washing. Most of the flocs will be removed in the surface fine media layer as the head loss increased significantly during operation. As a result, the majority of filter layer does not contribute to floc removal at all. Even through treated water quality could be achieved by using fine filter media in the upper layer, the head loss will be quite large and the filtration run time will be hindered. On the other hand, using coarse filter medium in upper layer will result in flocs penetration, longer filtration run time and better backwashing efficiency. Turbidity removal and suspended soilds retention ability could increase significantly if multimedia are applied in which the media size gradually decreases with the the same firection of water flow.
In order to understand the influence of the filtration medium composition in the water purification process, this study focused on exploring the differences between filtration operations using the same source water but different filter rates in two separated set of filtration units, a full size tank and a small size-pilot unit. Samples were also collected in different operational stages to analyse the concentration of manganese and aluminum by colorimetric methods.
After 30 hours operation, flocs were accumulated in the upper layer of the dual-filter full size unit (40cm of 0.9mm coal on the top, 30 cm of 0.45mm sand in the buttom, L/D is 1100). While in the single filter medium (90cm of 0.9cm sand, L/D is 1000) pilot unit, flocs were accumulated in the middle. Microorganisms were found in the upper and middle layers. It was also found that the expansion rate of single filter was only 5.5 % under the same backwashing flow rate (21m/d), not enough to restore a clean media.
Turbidity, manganese and aluminum particles could pass through the filter layer during early(<2-4 hrs) and late(>24 hrs) stage of operation. This penetration was enhanced when filtration rate was increased. Dual-filter filtration performed better than the single filter regardless of the flowrate. The difference of removal efficiency was 10% between dual and single filter when the filter rate was 160 m/d and could increased up to 50 % when flowrate was 230 m/d.
Water head increasing rate of the dual-filter was much higher than the single fileter unit. The difference went up to 4 times in the end of operation. Full head of the dual media unit could be reached in 24 hours when filtration rate was maintained at 230 m/d.
Overall, no significant water quality difference between dual and singal filter when operated under the low rate condition (<160m/d) could be identified. However, single filter medium unit showed poor treatment efficiency when operated under high flowrate condition (>200m/d). Water head of the single filter unit was only 1/4 of the dual-media unit in the end. Currently, there are 18 filtrations units on site. The treatment quantity will be promoted and water quality will be monitored continuously by changing the filters in different pools graduatly. The backwashing efficiency (increase to 30m/h) should be mointored with the change of filtration media.
URI: http://hdl.handle.net/11455/4956
其他識別: U0005-0208201117172500
Appears in Collections:環境工程學系所

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