本研究以淨化廢水含磷成分為宗旨，藉由流體化床反應器開發出一項新穎均相成核與結晶技術，達到回收單一成分、低含水分之磷酸金屬鹽結晶顆粒之永續資源化理念。首先，本實驗使用Ba2+、Sr2+當作反應的金屬藥劑，以化學沉澱法分別探討Ba2+、Sr2+於不同pH、金屬磷酸比 (Ba/P、Sr/P) 的條件下的除磷效率及汙泥組成種類。爾後，再以沉澱法所得數據結果為基礎，調整流體化床等各項參數，包括水利條件 (上流速度、截面負荷) 與出流pH等，開發均相成核與結晶之除磷技術。流體化床均相成核及結晶技術可以改善化學沉澱步驟產生大量污泥的二次汙染問題，並且在維持高除磷效率同時，得到具有經濟價值之低含水率結晶珠，有別於傳統流體化床技術必須利用SiO2等材質做為擔體所得到的異相成核結晶。
　　化學沉澱法結果顯示，Ba2+系統中，磷酸金屬鹽沉澱物組成分與溶液平衡pH值(pHf)及金屬沉澱劑加藥量(Ba2+)相關，如BaHPO4、Ba5(PO4)3(OH)，並直接影響除磷效率的優劣；此外，Sr2+則是以形成Sr5(PO4)3(OH)與SrHPO4之磷酸金屬鹽沉澱物為主， pHf 大於7會形成Sr5(PO4)3(OH)，此時金屬沉澱劑加藥量(Sr2+)為主要影響因子。
　　流體化床均相成核與結晶之結果顯示，添加金屬藥劑Ba2+與Sr2+可以成功產出均相磷酸金屬鹽結晶珠，其中水力條件並不會影響去除率及結晶率，並且粒徑分佈會受到過飽和度的影響，以此實驗參數運用到其他金屬離子進行流體化床除磷之均相成核反應，例如：鈣、鎂、錳、銅等，發現只要將水力條件經過適當的修正，也能夠成功產出各式磷酸金屬鹽結晶珠。

　　This work explores a novel homogeneous nucleation and crystallization technology using a Fluidized-bed reactor (FBR) for phosphate removal. Meanwhile, a support-free metallic phosphate orb with high purity and low water content can be generated. First, Ba2+ and Sr2+ cations were used as the coagulant reagent to carry out the chemical precipitation. The optimal conditions for precipitating the metallic phosphate sludge could be determined by the assessment of experimental parameters, including pH and molar ratios of metal to phosphate (Ba/P、Sr/P). Second, on the basis of the optimal conditions in chemical precipitation process, the hydraulic system (up-flow speed and cross-section loading) and effluent pH in FBR were further discussed to obtain the metallic phosphate orb through the homogeneous nucleation and crystallization mechanism. The homogeneous nucleation and crystallization process has proven to successfully solve the problems of producing large amounts of sludge in conventional chemical precipitation method.
　　In chemical precipitation stage, the phosphate removal and the components of sludge would strongly depend on the pH and Ba/P molar ratio. The precipitates could be BaHPO¬4 and Ba5(PO4)3OH by pH condition at the corresponding values. On the other hand, the majority of precipitates using Sr2+ is Sr5(PO4)3(OH) and SrHPO4, and the efficiency of phosphate removal is affected by the Sr/P molar ratio.
　　In homogeneous nucleation and crystallization stage, the hydraulic condition did not affect the total phosphate removal (TP%) and crystallization ratio of phosphate (CP%). Besides, the extent of supersaturation by controlling the effluent pH played an important role on the particle size distribution of metallic phosphate orb. Finally, the homogeneous nucleation and crystallization process was undertaken using Ca2+, Mg2+, Mn2+ and Cu2+ cations to in turn experience the phosphate removal by the careful examination of hydraulic conditions.

[1] G. K. Morse, et al., "Review: Phosphorus removal and recovery technologies," Science of The Total Environment, vol. 212, pp. 69-81, 1998.
[2] K. V. Kavanaugh M.C., Weber T.,Eugster J.,Roberts P.V.,, "Phosphorus removal by post-precipitation with Fe(III)," Jour. Water pollution Control Federation, vol. 50, pp. 216-234, 1978.
[3] H. S. W. Luedecke C., Jenkins D.,, "Precipitation of ferric phosphate in activated sludge:a chemival model and its verification," Water Sci. and Technol, vol. 21, pp. 325-337, 1989.
[4] K. Fytianos, et al., "Modelling of phosphorus removal from aqueous and wastewater samples using ferric iron," Environmental Pollution, vol. 101, pp. 123-130, 1998.
[5] N. Y. Seida Y., "Removal of phosphate in dissolution-coagulation process of layered double hydroxide," vol. 37, pp. 906-911, 2001.
[6] 張鈞期, "不同金屬藥劑的流體化床結晶技術處理含磷廢水之研究," 碩士論文, 化學工程研究所, 國立成功大學, 2009.
[7] M. M. Seckler, et al., "Calcium phosphate precipitation in a fluidized bed in relation to process conditions: A black box approach," Water Research, vol. 30, pp. 1677-1685, 1996.
[8] K. B. Elisabeth V. Munch, "Controlled struvite crystallization for removing phosphorus from anaerobic digester sidestreams," Water research, vol. 35, pp. 151-159, 2001.
[9] P. Battistoni, "Struvite crystallization:A feasible and reliable way to fix phosphorus in anaerobic supernatants," Water Research, vol. 34, pp. 3033-3041, 2000.
[10] P. Battistoni, "Phosphorus removal from a real anaerobic supernatant by struvite crystallization " Water rsearch, vol. 35, pp. 2167-2178, 2001.
[11] S. A. Parsons, "Struvite formation and the fouling propensity of different materials," Water Research, vol. 36, pp. 3971-3978, 2002.
[12] S. A. Parsons, "Struvite formation, control and recovery," Water Research, vol. 36, pp. 3925-3940, 2002.
[13] N. O. Nelson, et al., "Struvite precipitation in anaerobic swine lagoon liquid: effect of pH and Mg:P ratio and determination of rate constant," Bioresource Technology, vol. 89, pp. 229-236, 2003.
[14] J. Sellami, et al., "Experimental study on mixing and precipitation in a fluidized bed reactor," Powder Technology, vol. 157, pp. pp.163-167, 2005.
[15] K. Shimamura, et al., "Phosphorus recovery in a fluidized bed crystallization reactor," Journal of Chemical Engineering of Japan, vol. 39, pp. 1119-1127, 2006.
[16] Y. Song, "Nutrients removal and recovery by crystallization of magnesium ammonium phosphate from synthetic swine wastewater," Chemosphere, vol. 69, pp. 319-324, 2007.
[17] Y.-h. Song, et al., "Seed selections for crystallization of calcium phosphate for phosphorus recovery," Journal of Environmental Sciences, vol. 19, pp. 591-595, 2007.
[18] J. A. Wilsenach, "Phosphate and potassium recovery from source separated urine through struvite precipitation " Water Reserch, vol. 41, pp. 458-466, 2007.
[19] M. I. H. Bhuiyan, et al., "Phosphorus recovery from wastewater through struvite formation in fluidized bed reactors: A sustainable approach," vol. 57, ed, 2008, pp. 175-181.
[20] K. Kaikake, "Phosphate recovery from phosphorous-rich solution obtained from chicken manure incineration ash," Waste Management, vol. 29, pp. 1084-1088, 2009.
[21] 洪啟昌, "次磷酸溶液處理方法之研究-化學混凝法、吸附法與氧化法," 碩士論文, 化學工程研究所, 國立成功大學, 2005.
[22] G. M. G. Fair, J.C. and Okun, D.A., "Water and waste water engineering," vol. 2, 1968.
[23] W. Stumm, O'Melia, C. R., "Stoichometry of coagulation," J. Amer.Water Works Assoc., vol. 60, pp. 514-539, 1968.
[24] 陳政澤, "流體化床結晶反應槽回收廢水中重金屬鎘之研究," 國立中央大學環境工程研究所碩士論文, 1995.
[25] 陳奇琳, "倒錐流體化結晶床水動力對結晶動力之影響," 碩士論文, 資源環境工程所, 立德管理學院, 2006.
[26] 劉志忠, "流體化床結晶法去除水中磷酸鹽之研究," 國立中央大學環境工程研究所碩士論文, 1997.
[27] 陳寶琪, "微溶物系之沉澱與結晶," 國立台灣大學化學工程研究所博士論文, 1987.
[28] 石政怡, "次成核的機構和其在結晶程序上之應用," 國立台灣大學化學工程研究所博士論文 1996.
[29] A. E. Nielsen, Toft, J.M.,, "Electrolyte crystal growth kinetics," Journal of Crystal Growth, vol. 67, pp. 278-288, 1984.
[30] K. a. Mersmann, "On supersaturation during mass crystallization from solution," Chem. Engng Technol., vol. 13, pp. 50-62, 1990.
[31] 李敏華, 水質化學. 台南市: 復漢出版社, 1992.
[32] S. J. Markich, et al., "Divalent metal accumulation in freshwater bivalves: an inverse relationship with metal phosphate solubility," Science of The Total Environment, vol. 275, pp. 27-41, 2001.
[33] E. A. a. P. M. Quinton, "Bicarbonate Assay by X-reay analysis," American Chemical Society, vol. 54, pp. 791-793, 1982.
[34] W. Huang, et al., "Comparison of the Formation of Calcium and Barium Phosphates by the Conversion of Borate Glass in Dilute Phosphate Solution at near Room Temperature," Journal of the American Ceramic Society, vol. 90, pp. 838-844, 2007.
[35] S. S. Sung, et al., "Steady-state humic-acid-containing blanket in upflow suspended bed," Water Research, vol. 39, pp. 831-838, 2005.
[36] J. A. Dean, Lange's handbook of chemistry: Mcgraw-Hill, 1985.
[37] M. R. C. J. Christoffersen, N. Kolthoff, and O. Bärenholdt" Effects of strontium ions on growth and dissolution of hydroxyapatite and on bone mineral detection", Bone, vol. 20, 1997.
[38] M. A. A. By R. W. Mooney, C. W. W. Hoffman and R. C. Ropp, "Dimorphic Modifications of Dibasic Strontium Phosphate, SrHPO4," 1958.