Treatment of AP Solutions Extracted from Solid Propellant by NF/RO Membrane Process

NF/RO 멤브레인 공정을 적용한 고체추진제에서 추출된 암모늄 퍼클로레이트 (AP) 처리 연구

  • Kong, Choongsik (Beautiful Environment Construction Co., Ltd.) ;
  • Heo, Jiyong (Department of Civil and Environmental Engineering, University of South Carolina) ;
  • Yoon, Yeomin (Department of Civil and Environmental Engineering, University of South Carolina) ;
  • Han, Jonghun (Department of Civil and Environmental Sciences, Korea Army Academy) ;
  • Her, Namguk (Department of Civil and Environmental Sciences, Korea Army Academy)
  • 공충식 ((주)아름다운환경건설) ;
  • 허지용 (사우스캐롤라이나대학교 건설환경공학과) ;
  • 윤여민 (사우스캐롤라이나대학교 건설환경공학과) ;
  • 한종훈 (육군3사관학교 건설환경학과) ;
  • 허남국 (육군3사관학교 건설환경학과)
  • Received : 2012.06.15
  • Accepted : 2012.08.16
  • Published : 2012.08.31

Abstract

Ammonium perchlorate (AP) is primarily derived from the process of liquid incineration treatment when dismantling a solid rocket propellant. A series of batch dead-end nanofiltration (NF) and reverse osmosis (RO) membrane experiments were conducted to explore the retention mechanisms of AP under various hydrodynamic and solution conditions. Low levels of silicate type of siloxane had been detected through the GC/MS and FTIR analysis of liquid solutions extracted from solid ammonium perchlorate composite propellant (APCP). It is indicated that NF/RO membranes fouling in the presence of APCP was mainly attributed to the AP interactions because the concentration of silicate type of siloxane was negligible compared to that of AP. The osmotic pressure of AP was presumably resulted in the flux declines ranging from 13 to 17% in the case of the application of low-pressure (551 and 896 kPa for NF and RO) compared to those in application of high-pressure. The retention of AP by NF/RO membranes significantly varied from approximately 10 to 70% for NF and 26 to 87% for RO, depending on the operating and solution water chemistry conditions. The results suggested that retention efficiency of AP was fairly increased by reducing concentration polarization (i.e. application of low-pressure and stirring speed of 600 rpm) and increasing the pH of a solution. The result of this study was also consistent with the previous modeling of 'solute mass transfer of NF/RO membranes' and demonstrated that hydrodynamic and solution water chemistry conditions are to be a key factor in the retention of AP by NF/RO membranes.

로켓 추진기관의 해체 시 발생하는 고농도 암모늄 퍼클로레이트(AP)를 액상소각 처리 후 추가로 발생하는 저농도의 AP처리를 위해 NF/RO 멤브레인 공정을 적용하였고, 이때 AP제거 특성에 영향을 미치는 인자를 도출하기 위해 다양한 수리화학적 조건에서 전량여과방식으로 실험을 진행하였다. 고체 추진제에서 추출된 용액을 GC/MS와 FTIR분석을 통해 규산염 계열의 실록산 등을 검출하였으나, 이는 극미량이 포함되어 NF/RO 멤브레인 공정에 큰 영향을 미치지 않는 것으로 판단되었다. 상대적으로 낮은 압력의 운용조건에서는 높은 압력조건과 비교하여, 회수율 증가에 따라 농축된 AP의 삼투압 기작이 투과플럭스에 영향을 미치게 되어 13~17% 가량 플럭스가 감소됨을 확인하였다. 또한 AP의 제거율은 수리화학적 운영조건의 변화(압력 및 교반 속도 등)에 따라 크게 좌우됨을 알 수 있었고, 이 경우 NF와 RO 멤브레인 제거율은 각각 10~70%와 26~87% 가량 크게 달라짐을 확인하였다. 본 논문을 통해 NF/RO 멤브레인 공정을 적용한 AP 제거 기작에서 수리화학적 운영조건의 변화에 따른 농도분극, 멤브레인 선택성 및 삼투압 영향이 중요 지배 기작이었으며, 이는 'NF/RO 멤브레인의 물질이동과 선택성'의 기존 이론적 모델과 부합하였다.

Keywords

Acknowledgement

Supported by : 국방과학연구소

References

  1. E. T. Urbansky, "Perchlorate as an environmental contaminant", Environ Sci Pollut Res Int., 9, 187 (2002). https://doi.org/10.1007/BF02987487
  2. E. N. Coppola, "Treatment technologies for perchlorate", Global Demilitarization Symposium & Exhibition (2007).
  3. R. T. Zoeller, "Environmental chemicals impacting the thyroid: Targets and consequences", Thyroid, 17, 811 (2007). https://doi.org/10.1089/thy.2007.0107
  4. National Academy of Sciences / National Research Council (NAS/NRC), "Health implications of perchlorate ingestion" National Academy Press, Washington, DC. (2005).
  5. US EPA, "Status of EPA's interim assessment guidance for perchlorate" (2003).
  6. Ministry of Environment, Korea, "Drinking water quality criteria mandatory monitoring contaminants" (2010).
  7. T. Kim, K. Yeon, J. Cho, and S. Moon, "Analysis of EDCs by mass spectrometry and their removal by membrane filtrations", Membrane Journal, 15, 297, (2005).
  8. J. Ledgard, "The preparatory manual of black powder and pyrotechnics", version 1.4, Chemistry Non- Fiction (2007).
  9. A. Tandon, S. K. Gupta, and G. P. Agarwal, "Modeling of protein transmission through ultrafiltration membranes", J. Membr. Sci., 97, 83 (1994). https://doi.org/10.1016/0376-7388(94)00149-S
  10. N. O. Becht, D. J. Malik, and E. S. Tarleton, "Evaluation and comparison of protein ultrafiltration test results: Dead-end stirred cell compared with a cross-flow system", Separation and Purification Technolory, 62, 228 (2008). https://doi.org/10.1016/j.seppur.2008.01.030
  11. Z. Wang, Z. Chu, and X. Zhang, "Study of a cake model during stirred dead-end microfiltration", Desalination, 217, 127 (2007). https://doi.org/10.1016/j.desal.2007.02.010
  12. S. Lee, G. Amy, and J. Cho, "Applicability of sherwood correlations for natural organic matter (NOM) transport in nanofiltration (NF) membranes", J. Membr. Sci., 240, 49 (2004). https://doi.org/10.1016/j.memsci.2004.04.011
  13. B. Van der Bruggen, J. Schaep, D. Wilms, and C. Vandecasteele, "Influence of molecular size, polarity and charge on the retention of organic molecules by nanofiltration", J. Membr. Sci., 156, 29 (1999). https://doi.org/10.1016/S0376-7388(98)00326-3
  14. A. Braghetta, F. A. Digiano, and W. P. Ball, "Nanofiltration of natural organic matter: pH and ionic strength effects", J. Environ. Eng., 123, 628 (1997). https://doi.org/10.1061/(ASCE)0733-9372(1997)123:7(628)
  15. R. Boussahel, A. Montiel, and M. Baudu, "Effects of organic and inorganic matter on pesticide rejection by nanofiltration", Desalination, 145, 109 (2002). https://doi.org/10.1016/S0011-9164(02)00394-6
  16. V. Freger, T. C. Arnot, and J. A. Howell, "Separation of concentrated organic/inorganic salt mixtures by manofiltration", J. Membr. Sci., 178, 185 (2000). https://doi.org/10.1016/S0376-7388(00)00516-0