模型適當性與常態性假設檢驗

如果模型正確且所有的假定都滿足，則其殘差配適值應該是無結構的，特別 的是它們應該與任何其他變數包括所預測的反應是無相關的。一種簡易的檢驗就 是畫出殘差對配適值的圖形如Figure 4-15所示，圖中並沒有不尋常的結構出現 (如像漏斗型或麥克風型)，表示模型為正確且滿足所有的假定。但卻由左而右有 逐漸分散的趨勢，不過搭配殘差的常態分佈圖來看，其結果仍然是滿足所有的假 定。通常畫出殘差的直方圖可以檢驗常態假定，如果誤差項的假定被滿足，則這 個直方圖應該看起來像一組來自中心為零的常態分配樣本。不幸的是當樣本小時 經常發生相當的波動，使得溫和偏離常態的圖形並非一定意謂著嚴重違反假定，

但大幅偏離常態卻是相當嚴重的事而需要進一步分析。建構一個殘差的常態機率 圖如 Figure 4-16 所示，是一種非常有用的方法，結果顯示圖形皆成一條線，表 示誤差分配的確是常態，亦即該實驗數據符合常態分佈性的假設。

Fitted Value

Residual

0.0425 0.0400

0.0375 0.0350

0.0325 0.0300

0.0275 0.0250

0.004 0.003 0.002 0.001 0.000 -0.001 -0.002 -0.003 -0.004 -0.005

Residuals Versus the Fitted Values (response is reaction rate constant)

Figure 4-15 Residuals versus the fitted values for reaction rate constant

Residual

Percent

0.0075 0.0050

0.0025 0.0000

-0.0025 -0.0050

99

95 90

80 70 60 50 40 30 20

10 5

1

Normal Probability Plot of the Residuals (response is reaction rate constant)

Figure 4-16 Normal probability plot of the residuals for reaction rate constant

第五章 結論與建議

本研究主要探討利用 PVA 包覆微生物量及銅離子濃度對生物沉澱系統硫酸 還原效率之影響，並搭配反應曲面法分析找出最佳的評估指標及最佳的操作條 件。本章節根據以上之實驗結果可歸納出幾點結論及建議。

5-1 結論

1. 在中央合成設計實驗中，所有 PVA 固定化菌體顆粒試驗組在第 168 小時，

硫酸鹽還原率在99% 以上，而銅離子濃度則小於 1 mg/L，與 PVA 空白顆粒 之對照組實驗結果有明顯差異。

2. 在中央合成設計實驗中，結果顯示銅離子之物理化學沉澱 (含吸附作用) 量 介於17.0-64.6%，而生物沉澱量介於 35.4-83%，由此可知重金屬銅離子去除 途徑除了生物沉澱之外還包括物化作用的影響。

3. 實驗結果顯示各組最高硫離子濃度介於 34.8-57.2 mg/L，並由硫質量平衡計 算得知，其回收率介於59.4-79.9%。

4. 經 ANOVA 分析結果顯示，R4評估指標為顯著。而RSM 分析結果顯示其反 應曲面呈收斂之趨勢，有最佳值存在，當微生物濃度136 mg VSS/L (相當蛋 白質添加量1.12 mg)，銅離子濃度 57.9 mg/L，且反應溫度 30±2^oC 時，有最 高硫酸鹽還原之反應速率常數 0.0423 h^-1。經由廻歸係數分析得知硫酸鹽還 原之反應速率常數配適二階反應模型，其R²值為85.1%。

5-2 建議

1. 可嘗試不同 PVA 固定化之條件，如固定化材料及固定化方法對 PVA 固定化 菌體顆粒之生物活性及機械強度的影響，可進一步試驗分析。

2. 可嘗試以連續反應槽試驗不同操作條件，如 PVA 固定化菌體顆粒添加量、

HRT 及不同重金屬種類和濃度，對其硫酸還原效率及重金屬去除率之影響 做更深入之研究。

3. 可嘗試 PVA 固定化菌體顆粒對不同重金屬之吸附研究，並區分出生物沉澱、

化學沉澱及顆粒表面吸附作用之差異性。

第六章 參考文獻

1. APHA, AWWA, WEF. Standard Methods for the Examination of Water and Wastewater. American Public Health Association/American Water Works Association/Water Environment Federation, Washington DC, USA, 2005.

2. Azabou, S., Mechichi, T. and Sayadi, S. Zinc precipitation by heavy-metal tolerant sulfate-reducing bacteria enriched on phosphogypsum as a sulfate source.

Minerals Enginnering, 20, pp. 173-178, 2007.

3. Bradford, M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical Biochemistry, 72, pp. 248-254, 1976.

4. Cabrera, G.., Perez, R., Gomez, J. M., Abalos, A. and Cantero, D. Toxic effects of dissolved heavy metals on Desulfovibrio vulgaris and Desulfovibrio sp. Strains.

Journal of Hazardous Materials, 135, pp. 40-46, 2006.

5. Chang, C. C. and Tseng, S. K. Immobilization of Alcaligense eutrophus using PVA crosslinked with sodium nitrate. Biotechnology techniques, 12, pp. 865-868, 1998.

6. Chang, I.S., Shin, P. K. and Kim, B. H. Biological treatment of acid mine drainage under sulfate-reducing conditions with solid waste materials as substrate. Water Research, 34, pp. 1269-1277, 2000.

7. Chen, B. Y., Utgikar, V. P., Stephen, M. H., Tabak, H. H., Bishop, F. D. and Govind, R. Studies on biosorption of zinc (Ⅱ) and copper (Ⅱ) on Desulfovibrio desulfuricans. International Biodeterioration and Biodegradation, 46, pp. 11-18, 2000.

8. Chen, K. C., Lee, S. C., Chin, S. C. and Houng, J. Y. Simultaneous carbon-nitrogen removal in wastewater using phosphorylated PVA-immobilized microorganisms. Enzyme Microbiology Technology, 23, pp. 311-320, 1998.

9. Cheng, K. C. and Lin, Y. F. Immobilization of microorganisms with phosphorylated polyvinyl alcohol (PVA) gel. Enzyme Microbiology Technology, 16, pp. 79-83, 1994.

10. Cohen, Y. Biofiltration the treatment of fluids by microorganisms immobilized into the filter bedding material: a review. Bioresource Technology, 77, pp. 257-274,

sulfate-reducing bacteria; results from a bench scale experiment. Water Research, 30, pp. 1617-1624, 1996.

12. Chuichulcherm, S., Nagpal, S., Peeva, L. and Livingston, A. Treatment of metal-containing wastewaters with a novel extractive membrane reactor using sulfate-reducing bacteria. Journal of Chemical Technology and Biotechnology, 76, pp. 61-68, 2001.

13. Diaz, M. J., Eugenio, M. E., Timenez, L., Madejon, E. and Cabrera, F. Modelling vinasse/cotton waste ratio incubation for optimum composting. Chemical Engineering Journal, 93, pp. 233-240, 2003.

14. Diels, L., Spaans, P. H., Van Roy, S., Hooyberghs, L., Ryngaert, A., Wouters, H., Walter, E., Winters, J., Macaskie, L., Finlay, J., Pernfuss, B., Woebking, H., Pümpel, T. and Tsezos, M. Heavy metals removal by sand filters inoculated with metal sorbing and precipitating bacteria. Hydrometallurgy, 71, pp. 235-241, 2003.

15. El Bayoumy, M., Bewtra, J. K., Ali, H. I. and Biswas, N. Removal of heavy metal and COD by SRB in UAFF reactor. Journal of Environmental Engineering, 125, pp. 532-539, 1999.

16. Hao, O. J., Huang, L., Chen, J. M. and Buglass, R. L. Effects of metal additions on sulfate reduction activity in wastewater. Toxicological and Environmental Chemistry, 46, pp. 197-212, 1994.

17. Jong, T. and Parry, D. L. Removal of sulfate and heavy metals by sulfate reducing bacteria in short-term bench scale upflow anaerobic packed bed reactor runs.

Water Research, 37, pp 3379-3389, 2003.

18. Karnachuk, O. V., Kurochkina, S. Y., Nicomrat, D., Frank, Y. A., Ivasenko, D. A., Phyllipenko, E. A. and Tuovinen, O. H. Copper resistance in Desulfovibrion strain R2. Antonie Van Leeuwenhoek, 83, pp. 99-106, 2003.

19. Karri, S., Reyes, S. A. and Field, J. A. Toxicity of copper to acetoclastic and hydrogenotrophic activities of methanogens and sulfate reducers in anaerobic sludge. Chemosphere, 62, pp. 121-127, 2006.

20. Liamleam, W. and Annachhatre, A. P. Electron donors for biological sulfate reduction. Biotechnology Advances, 25, pp. 452-463, 2007.

21. Loka Bharathi, P. A., Sathe, V. and Chandramohan, D. Effect of lead, mercury and cadmium on sulfate-reducing bacteria. Environmental Pollution, 67, pp. 361-374, 1990.

22. Long, Z., Huang, Y., Cai, Z., Cong, W. and Ouyang, F. Immobilization of

Acidithiobacillus ferrooxidans by a PVA-boric acid method for ferrous sulphate oxidation. Process Biochemistry, 39, pp. 2129-2133, 2004.

23. Malik, .A. Metal bioremediation through growing cells. Environment International, 30, pp. 261-278, 2004.

24. Neculita, C. M., Zagury, G. J., and Bussiere, B. Passive treatment of acid mine drainage in bioreactors using sulfate-reducing bacteria: critical review and research needs. Journal of Environmental Quality, 36, pp. 1-16, 2007.

25. Radhika, V., Subramanian, S. and Natarajan, K. A. Bioremediation of zinc using Desulfotomaculum nigrificans: Bioprecipitation and characterization studies.

Water Research, 40, pp. 3628-3636, 2006.

26. Poulson, S. R., Colberg, P. J. S. and Drever, J. I. Toxicity of heavy metals (Ni, Zn) to Desulfovibrio desulfuricans. Geomicrobiology Journal, 14, pp. 14-49, 1997.

27. Rostron, W. M., Stuckey, D. C. and Young, A. A. Nitrification of high strength ammonia wastewater: comparative study of immobilization media. Water Research, 35, pp. 1169-1178, 2001.

28. Song, Y. C., Piak, B. C., Shin, H. S. and La, S. J. Influence of electron donor and toxic materials on the activity of sulfate reducing bacteria for the treatment of electroplating wastewater. Water Science and Technology, 38, pp. 187-194, 1998.

29. Techapun, C., Charoenrate, T., Watanabe, M., Sasaki, K. and Poosaran, N.

Optimization of thermostable and alkaline-tolerant cellulose-free xylanase production from agricultural waste by thermotolerant streptomyces sp. Ab106, using the central composite experimental design. Biochemical Engineering Journal, 12, pp. 99-105, 2002.

30. Thauer, R. K., Stackebrandt, E. and Hamilton, W. A. Energy metabolism and phylogenetic diversity of sulphate-reducing bacteria. In: Sulphate-reducing Bacteria (Edited by Barton L.L. and Hamilton W. A.). Cambridge University Press, New York, pp. 1-37, 2007.

31. Utgikar, V. P., Chen, B. Y. Chaudhary, H., Tabak, H. H., Haines, J. R. and Govind, R. Acute toxicity of heavy metals to acetate-utilizing mixed cultures of sulfate-reducing bacteria: EC100 and EC50. Environmental Toxicological and Chemistry, 20, pp. 2662-2669, 2001.

32. Utgikar, V. P., Stephen, M. H., Chaudnary, N., Tabak, H. H., Govind, R. and

2002.

33. Utgikar, V. P., Tabak, H. H., Haines, J. R. and Govind, R. Quantification of toxic and inhibitory impact of copper and zinc on mixed cultures of sulfate-reducing bacteria. Biotechnology and Bioengineering, 82, pp. 306-312, 2003.

34. Vargas, de I., Macaskie, E L. and Guibal, E. Biosorption of palladium and platinum by sulfate-reducing bacteria. Journal of Chemical Technology and Biotechnology, 79, pp. 49-56, 2004.

35. Waybrant, K. P., Blowers, D. W. and Ptacek, C. J. Selection of reactive mixtures for use in permeable reactive walls for treatment of acid mine drainage.

Environmental Science technology, 32, pp. 1972-1979, 1998.

36. White, C. and Gadd, G. M. Mixed sulphate-reducing bacterial cultures for bioprecipitation of toxic metals: factorial and response-surface analysis of effects of dilution rates, sulfate and substrate concentration. Microbiology, 142, pp.

2197-2205, 1996.

37. White, C., Sayer, J. A. and Gadd, G. M. Microbial solubilization and immobilization of toxic metals: key biogeochemical process for treatment of contamination. FEMS Microbiology Reviews, 20, pp. 503-516, 1997.

38. Zagury, G. J., Kulnieks, V. and Neculita, C. M. Characterization and reactivity assessment of organic substrates for sulfate-reducing bacteria in acid mine drainage treatment. Chemosphere, 64, pp. 944-954, 2006.

39. 王姮娟，蔡士昌，「重金屬廢水處理技術 (下)」，台灣環保產業雙月刊，第二 十七期，17~19 頁，民國九十三年。

40. 朱昱學，「節水善其事必先利其器」，節約用水季刊，Vol. 19，民國八十九年。

41. 吳美惠，張芳賓，朱昱學，「固定化微生物廢水處理技術評估」，工業污染防 治，第五十九期，81~109 頁，民國八十五年。

42. 林瑩峰，「微生物固定化技術應用於脫硝程序之研究」，國立清華大學化學工 程研究所博士論文，民國八十二年。

43. 陳國誠，「生物固定化技術與產業應用」，茂昌，臺北市，民國八十九年。

44. 侯萬善，「廢水金屬處理回收技簡介」，中技社通訊，第四十八期，4-7 頁，民 國九十二年。

45. 楊佳紘，「生物沈澱程序中重金屬對硫酸還原效率的影響」，國立交通大學環 境工程研究所碩士論文，民國九十四年。