Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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Effects of $CaF_2$ dosage, pH and Treated Water Recirculation on Fluoride Removal in Treating Semiconductor Wastewater with Fluidized bed Reactor (FBR)

유동상 반응기를 이용한 반도체 폐수 내 불소 처리 시 $CaF_2$ 주입량, pH 및 처리수 재순환의 영향

  • An, Myeong-Ki (Department of Environmental Engineering, Chungbuk National University) ;
  • Kim, Jin-Sik (Department of Environmental Engineering, Chungbuk National University) ;
  • Kim, Keum-Yong (Department of Environmental Engineering, Chungbuk National University) ;
  • Ryu, Hong-Duck (Department of Environmental Engineering, Chungbuk National University) ;
  • Lee, Sang-Ill (Department of Environmental Engineering, Chungbuk National University)
  • Received : 2010.03.04
  • Accepted : 2010.06.04
  • Published : 2010.06.30
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Abstract

The optimum condition for fluoride removal, water content reduction, and $CaF_2$ purity was determined in treating semiconductor waste water in which ammonia nitrogen, phosphorus, and fluoride are existed simultaneously using a fluidized bed reactor. Effects of pH, seed dosage, and recirculation of treated water were investigated through lab-scale experiments. Considering fluoride removal, sludge purity, and water content, that pH 5 and seed dose of 150 g were found to be optimum. Correspondingly, removal of fluoride and phosphate (${PO_4}^{3-}$-P) was 94.24% and 8.97%, respectively, with water content ratio of 12.94%. Increase in an amount of seed dosage not only enhance fluoride removal efficiency, but also buffer fluoride removal-reducing effect due to the variation of recirculation ratio of treated water and pH.

본 연구에서는 유동상 반응기를 이용하여 고농도의 질소, 인 및 불소가 동시에 존재하는 반도체 폐수 내 불소 처리시 불소 제거효율 향상, 함수율 저감 및 생성 슬러지($CaF_2$)의 순도 향상을 꾀하고자 하였다. 이를 위해 pH 및 seed 주입량, 유출수의 순환여부에 따른 영향을 살펴본 결과 유출수 재순환 시 불소제거효율, 슬러지 순도 및 함수율을 모두 고려할 경우 최적의 pH는 5, seed 주입량은 150 g으로 관찰되었다. 이때의 불소 및 인 제거효율은 94.24 및 8.97%로 나타났고, 함수율은 12.94%로 확인되었다. Seed 주입량의 증가는 불소제거효율을 증가시킬 뿐만 아니라 유출수 재순환 및 pH 변동에 따른 불소제거효율 감소도 억제시키는 것으로 나타났다.

Keywords

References

  1. 우귀남, "$CaF_2$ 결정화 공법을 이용한 반도체 폐수의 불소처리," 충북대학교 석사논문(2009).
  2. 변혜정, "시멘트 페이스트를 이용한 불산폐수 처리에 관한 연구," 한양대학교 석사논문(2007).
  3. 김영임, 김동수, "칼슘 침전법에 의한 불소 처리에 관한 연구," 한국물환경학회지, 23(3), 371-376(2007).
  4. 나재식, "소석회와 희토류 흡착제를 이용한 불소 제거 연구," 신기술 연구 논문집, 28, 181-187(1999).
  5. Aldaco, R., Garea, A., and Irabien, A., "Fluoride Recovery in a Fluidized bed: Crystallization of Calcium Fluoride on Silica Sand," Ind. Eng. Chem. Res., 45(2), 796-802(2006). https://doi.org/10.1021/ie050950z
  6. Garea, A., Aldaco, R., and Irabien, A., "Improvement of calcium fluoride crystallization by means of the reduction of fine formation," Chem. Engrg. J., 154(1-3), 231-235(2009). https://doi.org/10.1016/j.cej.2009.04.050
  7. 한국과학기술정보연구원, "수처리 신진기술 동향," 15-23(2005).
  8. Parthasarathy, N., Buffle, J., and Haerdi, W., "Combined use of calcium salts and polymeric aluminium hydroxide for defluoridation of waste waters," Water Res., 20(4), 443-448 (1986). https://doi.org/10.1016/0043-1354(86)90191-0
  9. Aldaco, R., Garea, A., and Irabien, A., "Calcium fluoride recovery from fluoride wastewater in a fluidized bed reactor," Water Res., 41(4), 810-818(2007). https://doi.org/10.1016/j.watres.2006.11.040
  10. 이명진, 박세진, 김창균, 윤태일, "Calcium chloride와 alum을 이용한 불소제거," 대한환경공학회지, 24(12), 2151-2161(2002).
  11. Aldaco, R., Irabien, A., and Luis, P. "Fluidized bed reactor for fluoride removal," Chem. Engrg. J., 107, 113-117(2005). https://doi.org/10.1016/j.cej.2004.12.017
  12. Aldaco, R., Garea, A., and Irabien, A., "Particle growth kinetics of calcium fluoride in a fluidized bed reactor," Chem. Eng. Sci., 62, 2958-2966(2007). https://doi.org/10.1016/j.ces.2007.02.045
  13. 안명기, 김금용, 류홍덕, 이상일, "Fluidized Bed Reactor(FBR)를 이용한 반도체 폐수의 불소처리," 대한환경공학회지, 32(5), 437-442(2010).
  14. Raichur, A. M., and Jyoti Basu, M., "Adsorption of fluoride onto mixed rare earth oxides," Sep. Purif. Technol., 24, 121-127 (2001). https://doi.org/10.1016/S1383-5866(00)00219-7
  15. Tang, Y., Guan, X., Wang, J., Gao, N., McPhail, M. R., and Chusuei, C. C., "Fluoride adsorption onto granular ferric hydroxide : effects of ionic strength, pH, surface loading, and major co-existing anions," J. Hazard. Mater., 171, 774-779 (2009). https://doi.org/10.1016/j.jhazmat.2009.06.079
  16. Macasklll, J. B., and Bates, R. G., "Solubility product constant of calcium fluoride," J. Phys. Chem. A., 81(5), 496-498(1976).
  17. de Vreugd, C. H., ter Horst, J. H., Durville, P. F. M., Witkamp, G. J., and van Rosmalen, G. M., "Adsorption behaviour of polyelectrolytes on calcium fluoride Part I: influence of the pH and the ionic strength on the adsorption isotherms," Colloids Surf., A., 154(3), 259-271(1999). https://doi.org/10.1016/S0927-7757(98)00882-6
  18. ter Horst, J. H., Wong Fong Sang, K. E., de Vreugd, C. H., Geertman, R. M., Witkamp, G. J., and van Rosmalen, G. M., "Adsorption behaviour of polyelectrolytes on calcium fluoride Part II: molecular modeling of the adsorption behaviour," Colloids Surf., A., 154(3), 273-284(1999). https://doi.org/10.1016/S0927-7757(98)00883-8
  19. Amjad, Z., "Performance of Inhibitors in Calcium Fluoride Crystal Growth Inhibition," Langmuir., 9(2), 597-600(1993). https://doi.org/10.1021/la00026a039
  20. 김영임, 백미화, 김동수, "처리수 재사용을 위한 칼슘 침전법에 의한 불소폐수 처리 특성," 한국자원리싸이클링학회, 16(4), 27-32(2007).
  21. 정윤호, "응집침전에 의한 제강폐수 중의 불소제거에 관한 연구," 순천대학교 산업대학원 석사논문(2002).