| 摘要(英) |
Coagulation is an important solid-liquid separation process in potable water/wastewater treatment. Among all the control factors for coagulation, the dosage of coagulant is the most difficult to control. The dosage of coagulant is usually determined by jar test or the experience of operators, which usually leads to an overdose of coagulant. Overdose of coagulant causes high cost for chemicals and for on sludge treatment. So far, in our laboratory, a monitoring system for coagulation process, floc image colorimetric analysis (FICA), to resolve the problems mentioned above has been developed; however, the responses of the monitoring system for various coagulation conditions are not clear and the applications of the system in the control of coagulant dosage have not been clarified yet.
In this research, modeled turbid water is made by kaolin particles. The responses of the FICA to various coagulation conditions, such as initial turbidity, solution pH, and coagulant dosage were investigated. The evolution of RGB values of the suspension images were analyzed.
During coagulation, the solution images varied as the particles grew; as the consequence, the RGB values of the images changed correspondingly.. When the coagulation was effective, the RGB values decreased significantly within rapid-mixing. Then, as the flocs became bigger, the RGB values jumped up as the flocs passing through the observation window and dropped down due to the clear solution during the slow-mixing process. It was found that the slope of the RGB values during rapid-mixing could be used to monitor the coagulation efficiency. As the coagulation efficiency increased, the solution becomes clearer and, thus, the RGB dropped significantly and the slope of RGB values increased. .It is also found that the optimal dosage of coagulant occurred when the slopes of RGB values first hit the bottom. In other words, the optimal coagulation condition could be determined right after the rapid-mixing from jar test, which is much faster than the traditional method. In addition, the standard deviation of the RGB values increased with increasing particle size due to brighter images of flocs.
|
| 參考文獻 |
1. W. Stumm, and J. J. Morgan, “The Solid-Solution Interface”, Aquatic Chemistry, pp.612-614,(1981).
2. A. Amirtharagjah, and C.R. O'Melia, “Coagulation Processes: Destabilization, Mixing and Flocculation”, Water Quality & Treatment.4th, pp.269-365,(1990).
3. Y. Ganz, “Water Treatment”, American Water Works Association, 1, (2003).
4. 徐宏銘，”應用流導電流偵測技術決定混凝最佳加藥量之研究”，國立交通大學環境工程研究所碩士論文，1992。
5. S. Bishop, “Use of the Streaming Current Detector at Langsett Water-Treatment Works”, Water and Environment, 6(3), pp. 1-9, (1992)
6. 張進興，”應用流導電流偵測技術用於淨水場混凝加藥自動控制之研究”，國立交通大學環境工程研究所碩士論文，1993。
7. H. W. Ching, M. Elimelech and J. G. Hering, “Dynamics of coagulation of clay particles with aluminum sulfate”, Journal of Environmental Engineering, 120(1), pp.169-189, (1994).
8. T. O. Kayode, and J. Gregory , “A new technique for monitoring sludge conditioning”, Water Research, 22(1), pp.85-90, (1988).
9. Photometric Dispersion Analyser PDA2000 Operating Manual, Rank Brothers Ltd.
10. J. Gregory, and D.W. Nelson, “A new optical method for flocculation monitoring”, Solid-Liquid Separation, Ellis Horwood, Chichester, pp. 172–182, (1984).
11. J. Gregory, and W. D. Nelson, “Monitoring of aggregates in flowing suspension”, Colloid and Surfaces., 18, pp.175~188, (1986).
12. J. Eisenlauer, and D. Horn, “Fiber-optic sensor for flocculant dose control in flowing suspension”, Colloid and Surfaces, 14, pp.121~134, (1985).
13. 甘其銓，”淨水場濁度去除效能評估及混凝監測之研究—以豐原淨水場為例”，國立交通大學環境工程研究所碩士論文，新竹(1997)。
14. 吳如雅，”非接觸式光學監測混凝系統技術之發展”，國立中央大學碩士論文，桃園(2008)。
15. 劉倚汎，”以光學影像連續監測銅廢水化學沉降之技術發展”，國立中央大學碩士論文，桃園(2009)。
16. 鄭伯左編著，色彩理論與數位應像，新文京開發出版股份有限公司(2004)。
17. 鄭國裕編著，電腦影像處理，藝風堂出版。
18. M. Elimelech, J. Gregory, X. Jia, and R.A. Williams, “Particle deposition and aggregation-measurement, modeling and simulation”, Elsevier, (1995).
19. 余瑞芳、鄭文伯、朱美玲，“監測廢水中懸浮微粒粒徑分佈之系統與方法”，經濟部智慧財產局，中華民國專利96108076 (2007)。
20. 鄭文伯、高瑜苹、余瑞芳，“利用濁度量測值之變異性來推估膠凝過程膠羽顆粒成長趨勢之系統與方法”，中華民國專利96119832(2007)。
21. 宋慧琴，“眼應用光學基礎”，新文京開發出版股份有限公司，台北(2007)。
22. J. Leentvaar, M. Rebhun, “Strength of ferric hydroxide flocs” , Water Research, 17, pp.895–902, (1983).
23. G.R. Xu, C.S.B. Fitzpatrick, J. Gregory, “Floc formation, size distribution, and its transformation detected by online laser particle counter”, Separation Science and Technology, 43, pp.1725–1736, (2008).
24. C.-J. Chin, S. Yiacoumi, C. Tsouris, S. Relle, S. B. Grant, “Secondary minimum separation of superparamagnetic colloidal particles”, Langmuir, 16, pp.3641–3650, (2000).
25. R.K. Chakraborti, J.F. Atkinson, and J. E. Benschoten, “Characterization of alum floc by image analysis”, Environmental Science & Technology, 34, pp.3969–3976, (2000).
26. R.-F. Yu, H.-W. Chen, W.-P. Chen, M.-L. Chu, “Simultaneously monitoring the particle size distribution, morphology and suspended solids concentration in wastewater applying digital image analysis (DIA) ”, Environmental Monitoring and Assessment, 148, pp.19–26, (2009)
27. 雷一弘、廖述良，“發明專利說明書-水中色度監測儀”，經濟部智慧財產局，台北(1990)。
28. R. L. Droste, “Theory and practice of water and wastewater treatment”, John Wiley & Sons Inc,(1996).
29. J. Gregory, and J. Duan, “Hydrolyzing metal salts as coagulants”, Pure and Applied Chemistry, 73(12), pp. 2017–2026, (2001)
30. P. Jarvis, B. Jefferson, J. Gregory, and S.A. Parsons, “A review of floc strength and breakage”, Water Research, 39(14), pp. 3121-3137, (2005)
|
[Endnote RIS 格式]
[相關文章]
[文章引用]
[完整記錄]
[館藏目錄]
至系統瀏覽論文 ( 永不開放)
plurk
funp
live
udn
HD
myshare
netvibes
friend
youpush
delicious
baidu
Google bookmarks
del.icio.us
hemidemi
facebook
twitter
google
reddit