Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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Effect of Struvite Crystallization Kinetics; Seed Material, Seed Particle Size, $G{\cdot}t_d$ Value

Struvite 결정화에 미치는 영향; Seed 물질, Seed 입자크기, $G{\cdot}t_d$ Value의 영향

  • Kim, Jin-Hyoung (Department of Environmental Engineering, Chungbuk National University) ;
  • Kim, Keum-Yong (Department of Environmental Engineering, Chungbuk National University) ;
  • Kim, Dae-Keun (Department of Environmental Engineering, Chungbuk National University) ;
  • Park, Hyoung-Soon (Department of Environmental Engineering, Chungbuk National University) ;
  • Lee, Sang-Cheol (Department of Water Supply Development, Korea Water Resources Corporation) ;
  • Lee, Sang-Ill (Department of Environmental Engineering, Chungbuk National University)
  • 김진형 (충북대학교 환경공학과) ;
  • 김금용 (충북대학교 환경공학과) ;
  • 박형순 (충북대학교 환경공학과) ;
  • 김대근 (충북대학교 환경공학과) ;
  • 이상철 (한국수자원공사 수도개발처) ;
  • 이상일 (충북대학교 환경공학과)
  • Published : 2008.02.29
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Abstract

This study focused on shorten the period of the struvite crystal birth and development by adding seed materials. For this purpose, three different seed materials were selected: sand, anthracite and struvite. The experiments has been conducted to evaluate the effect of the particle size of the selected seed material on the struvite crystallization, and to study the mixing effect which can be expressed by the value of $G{\cdot}t_d$(the multiple of mean velocity gradient(G) and mixing time($t_d$)). It was observed in this study that the removal efficiency of ammonia nitrogen increased by 9%, 11%, and 20% for sand, anthracite, and struvite added as the seed material, respectivley. This indicated that the struvite crystallization efficiency had a close correlation with the specific surface area of the seed particle. It was found that when struvite was selected as the seed material, the struvite crystallization proceeded at lower $G{\cdot}t_d$ value as compared with other seed materials. This observation implied that the secondary crystal birth would be dominated in this reaction. It was concluded in this study that the particle size was not significant factor on the struvite crystallization, while the $G{\cdot}t_d$ value was a considerably important factor in terms of the theory of the struvite crystal birth.

본 연구에서는 seed 물질을 첨가함으로써 struvite 결정핵의 생성 및 성장단계를 단축시키고자 하였다. 본 연구에서는 seed 물질의 성상(모래, 안트라사이트, struvite)별, 입자의 크기(44$\sim$63 $\mu$m, 63$\sim$88 $\mu$m, 88$\sim$114 $\mu$m)별, 교반조건($G{\cdot}t_d$)에 따라 결정핵의 생성속도론에 미치는 영향을 관찰하였다. 모래와 안트라사이트는 seeding 하지 않은 경우에 비하여 암모니아성 질소제거효율이 각각 9%, 11%로 향상되었으며, struvite로 seed한 경우는 암모니아성 질소제거효율은 20% 이상 향상되었다. Seeding에 따른 struvite 결정화 효율은 seed 입자의 비표면적과 밀접한 상관관계가 있다. Seed 물질입자의 비표면적이 클수록 struvite 핵생성 및 성장을 향상시켰다. 또한 struvite 결정화 반응시 동질의 seed 물질(struvite seeds)을 사용하여 2차 핵생성을 유도하면 struivte 결정의 핵생성 및 성장을 위한 $G{\cdot}t_d$값을 단축시킬 수 있는 것으로 나타났다. 본 연구에서 고려한 입자크기에 대해서는 seed 입자크기에 대한 영향은 확인되지 않았다. Struvite 결정핵 생성속도론에서 $G{\cdot}t_d$값은 매우 중요한 인자로써 작용하였다.

Keywords

References

  1. Ali, M. I. and Schneider, P. A., "A fed-batch design approach of struvite system in controlled supersaturation," Chem. Eng. Sci., 61, 3951-3961(2006) https://doi.org/10.1016/j.ces.2006.01.028
  2. Jones, A. G., Crystallization Process System, Butterworth Heinemann, London(2002)
  3. Mullin, J. W., Crystallization. Butterworth Heinemann, London(1992)
  4. Le Corre, K. S., "Phosphorus Removal and Recovery from Wastewater Effluents by struvite crystallization: a review," Understanding Struvite Crystallization and Recovery, Cranfield University, UK(2006)
  5. UK. Scope Newsletter: Phosphate recovery by struvite precipitation in a stirred reactor Home page, http://www.nhm.ac.uk, July(2002)
  6. McCabe, W. L., Simith J. C., and Harriout, P.(ed.), Unit Operation of Chemical Engineers' Handbook, 6th ed., New York: McGraw-Hill, 1056(2005)
  7. Wu, Q. and Bishop., P. L. "Enhancing struvite crystallization from anaerobic supernatant," J. Environ. Eng. Sci., 3(1), 21-29(2004) https://doi.org/10.1139/s03-050
  8. Jang, H. and Kang, S. H., "Phosphorus removal using cow bone in hydroxyapatite crystallization," Water Res., 36, 1324-1330(2002) https://doi.org/10.1016/S0043-1354(01)00329-3
  9. Borgerding, J., "Phosphate deposits in digestion systems," J. Water Pollut. Control Fed., 44, 813-819(1972)
  10. Kofina, A. N. and Koutsoukos, P. G., "Spontaneous Precipitation of Struvite from Synthetic Wastewater Solutions," Crystal Growth and Design, 5(2), 489-496(2005) https://doi.org/10.1021/cg049803e
  11. Cornwell, D. A. and Bishop, M. M., "Determining Velocity Gradients in Laboratory and Full Scale Systems," J. AWWA, 53(1983)
  12. 김철환, "Nitrogen Removal of Semiconductor Wastewater by Struvite Crystallization," 충북대학교 공학석사학위 논문(2006)
  13. APHA, AWWA, WEF, "Standard methods for the examination of water and wastewater," 19th Edition, Edited by Andrew, D. E., Lenore, S.C., Arnold, E.G.(2005)
  14. Ohlinger, K. N., Young, T. M., and Schroeder, E. D., "Kinetics effects on preferential struvite accumulation in wastewater," J. Environ. Eng., 730-737(1999)
  15. Kim, D. K., Kim, J. H., Kim, K. Y., Park, H. S., and Lee, S. I., "Effect of Mixing Intensity and Duration on Struvite Crystallization for the Removal of N and P," 4th IWA-Leading Edge Conference and Exhibition on Water and Wastewater Technologies, International Water Association, Singapore, 41(2007)
  16. 원성연, 박승국, 이상일, "Struvite 결정화에 의한 질소 및 인의 제거," 대한환경공학회지, 22(4), 599-607(2000)
  17. Assender, H., Bliznyuk, V., and Porfyrakis, K., "How surface topography relates to materials properties," Science, 297, 973-976(2002) https://doi.org/10.1126/science.1074955