DOI QR코드

DOI QR Code

A Study on the Characteristics of Manufactured Mg Crown on the Calcining Conditions of Dolomite

백운석의 소성 조건에 따른 제조 Mg crown의 특성에 관한 연구

  • Hwang, Dae Ju (Advanced Materials Team, Korea Institute of Limestone and Advanced Materials) ;
  • Yu, Young Hwan (Advanced Materials Team, Korea Institute of Limestone and Advanced Materials) ;
  • Lee, Jong Dae (Department Chemical Engineering of Chungbuk National University)
  • 황대주 ((재)한국석회석신소연구소 첨단소재팀) ;
  • 유영환 ((재)한국석회석신소연구소 첨단소재팀) ;
  • 이종대 (충북대학교 화학공학과)
  • Received : 2021.06.09
  • Accepted : 2021.08.05
  • Published : 2021.11.01

Abstract

Mg crowns were manufactured using domestic dolomite (Ca·Mg(CO3)2) (20~30 mm). In order to manufacture the calcined dolomite (CaO·MgO), (a) electric furnace (950 ℃, 480 min) and (b) microwave furnace (950 ℃, 60 min) processes were used. As a result of XRD analysis, it was analyzed as (a) CaO 56.9 wt%, MgO 43.1 wt% by electric furnace process and (b) CaO 55 wt%, MgO 45 wt% by microwave furnace process. Even when the decarbonation reaction time of dolomite was shortened by 1/8 in microwave furnace process compare with electric furnace process, the calcined dolomite could be produced. The hydration reaction (ASTM C 110) is a standard for the hydration reactivity of calcined dolomite, and the calcined dolomite produced by electric furnace process showed a high hydration reactivity (max temp 79.8 ℃/1.5 minutes). Such hydration reactivity was occurred by only CaO hydration reaction and that was confirmed by XRD analysis. The calcined dolomite produced by microwave furnace process showed low hydration reactivity (max temp 81.7 ℃/19.5 minutes). Such low hydration reactivity was occurred by CaO and MgO hydration reaction due to the hydration reaction of CaO thereafter occurring of the hydration reaction of MgO, and that was confirmed by XRD analysis. The prepared Mg crown were 58.8 g and 74.6 g by electric furnace and microwave furnace processes, respectively, under the reaction conditions of 1,230 ℃, 60 min, 5 × 10-2 torr by silicothermic reduction.

국내에서 채광한 백운석(Ca·Mg(CO3)2) (20~30 mm)을 활용하여 Mg crown을 제조하였다. 백운석을 사용하여 경소 백운석(CaO·MgO)을 제조하기 위하여, (a) 전기로(950 ℃, 480분)와 (b) 마이크로웨이브 가열로(950 ℃, 60분)를 사용하는 공정을 적용한 결과를 서로 비교하였다. 전기로 공정의 경우에는 CaO 56.9 wt%, MgO 43.1 wt%, 마이크로웨이브 가열로 공정의 경우에는 CaO 55 wt%, MgO 45 wt%가 얻어졌다. 마이크로웨이브 가열로를 사용한 공정에서는 백운석의 탈탄산 반응 시간을 1/8로 단축하여도 경소백운석을 제조할 수 있었다. 수화 시험(hydration reaction, ASTM C110)은 경소백운석의 수화 반응성의 기준이 되는데, 전기로 공정의 경우에는 고 반응성(최고 온도 79.8 ℃/1.5 분)을 나타내었다. 이러한 수화 반응은 CaO의 수화 반응에 의해 일어나는 것을 XRD 분석 결과에서 확인할 수 있었으며, 마이크로 가열로 공정의 경우에는 저 반응성(최고 온도 81.7 ℃/19.5 분)을 나타내었다. 이러한 낮은 수화 반응성은 CaO의 수화 반응이 일어난 후에 MgO의 수화 반응이 일어나서 CaO와 MgO가 모두 수화물 형태로 되는 것을 XRD 분석 결과에서 확인하였다. 전기로와 마이크로웨이브 가열로를 사용하여 1,230 ℃, 60분, 5 × 10-2 torr의 조건에서 규소열환원 공정으로 제조한 Mg crown은 전기로 공정의 경우에 58.8 g 그리고 마이크로웨이브 가열로 공정의 경우에 74.6 g을 얻을 수 있었다.

Keywords

Acknowledgement

본 연구는 2016년도 산업통상자원부 및 한국산업평가관리원(KEIT) 연구비지원산업현장핵심수시기술개발사업(No. 10030711)에 의한 연구입니다.

References

  1. Pidgeon, L. M. and King, J. A., "The Vapour Pressure of Magnesium in the Thermal Reduction of MgO by Ferrosilicon," Trans. Farady Soc., 4, 197-206(1948). https://doi.org/10.1039/df9480400197
  2. Morsi, I. M., El Barawy, K. A. and Morsi, M. B., "Silicothermic Reduction of Dolomite Ore Under Inert Atmosphere," Canadian Metallurgical Quartely, 41, 15-28(2002). https://doi.org/10.1179/cmq.2002.41.1.15
  3. Choi, H., Park, R. L. and Park, D. G., "Design Optimization of Vertical Thermal Reduction System for Magnesium Production : Part(I) Thermal Reduction Region," Transactions of the KSME A, 10, 2502-2507(2010).
  4. Choi, H., Park, R. L. and Park, D. G., "Design Optimization of Vertical Thermal Reduction System for Magnesium Production : Part(II) Condensation Region," Transactions of the KSME A, 10, 2727-2732(2010).
  5. Zhang, C., Wang, C. and Zhang, S., "Experimental and Numerical Studies on a One-Step Method for the Production of Mg in the Silicothermic Reduction Process," Ind. Eng. Chem. Res., 54, 8883-8892(2015). https://doi.org/10.1021/acs.iecr.5b01830
  6. Choi, H., Park, D. G. and Kim, D. S., KR patent, 10-2011-0050743 (2011).
  7. Kim, M. C., Han, G. S. and Choi, G. S., KR patent, 10-2013-0051288(2013).
  8. Choi, H., Park, D. G. and Lee, J. G., KR patent, 10-2013-0075394 (2013).
  9. Han, G. S. and Park, D. G., KR patent, 10-2012-0074972(2010).
  10. Han, G. S. and Park, D. G., KR patent, 10-2012-0074971(2010).
  11. Ramakrishnan, S. and Koltun, P., "Global Warming Impact of the Magnesium Produced in China Using the Pidgeon Process," Resources, Conserv. Recycl, 42, 49-64(2004). https://doi.org/10.1016/j.resconrec.2004.02.003
  12. Gao, F., Nie, Z. and Wang, Z., "Life Cycle Assessment of Primary Magnesium Production Using the Pidgeon Process in China," Int J Life Cycle Assess, 14(5), 480-489(2009). https://doi.org/10.1007/s11367-009-0101-9
  13. Francesco, C., Marco, R. and Sergio, U., "LCA of Magnesium Production: Technological Overview and Worldwide Estimation of Environmental Burdens," Resources, Conserv. Recycl., 52, 1093-1100(2008). https://doi.org/10.1016/j.resconrec.2008.05.001
  14. Hwang, D. J., Ryu, J. Y. and Park, J. H., "Calcination of Megacrystalline Calcite Using Microwave and Electric Furnaces," J. Ind. Eng. Chem., 18(6), 1956-1963(2012). https://doi.org/10.1016/j.jiec.2012.05.011
  15. Hwang, D. J., Ryu, J. Y. and Park, J. H., "Preparation of CaCO3 Using Mega-crystalline Calcite in Electrical Furnace and Batch Type Microwave Kiln," J. Ind. Eng. Chem., 19(5), 1507-1516(2013). https://doi.org/10.1016/j.jiec.2013.01.017
  16. Hwang, D. J., Ryu, J. Y. and Yu, Y. H., "Characteristics of Precipitated Calcium Carbonate by Hydrothermal and Carbonation Processes with Mega-crystalline Calcite Using Rotary Microwave Kiln," J. Ind. Eng. Chem., 20(5), 2727-2734(2014). https://doi.org/10.1016/j.jiec.2013.10.061
  17. Hwang, D. J., Yu, Y. H. and Baek, C. S., "Preparation of High Purity PCC from Medium- and Low-grade Limestones Using the Strongly Acidic Cation Exchange Resin," J. Ind. Eng. Chem., 30, 309-321(2015). https://doi.org/10.1016/j.jiec.2015.05.038
  18. Cho, G. H., KR patent, 10-2013-0028299(2013).
  19. Hang, S., CN patent, 204594220(2015).
  20. Huang, Y. M. and Li, J. E., CN patent, 206457532(2017).
  21. Wada, Y., Suzuki, E. and Maitni, M., JP patent, 2015-222785(2015).
  22. Fukui, Y., Wada, Y. and Suzuki, E., JP patent, 2016-004089(2016).
  23. Hwang, D. J., Yu, Y. H. and Park, J. M., KR patent, 10-2017-0097006(2017).
  24. Huang, Y. M. and Li, J. E., CN patent, 106498185 A(2017).
  25. Huang, Y. M. and Li, J. E., CN patent, 106756107 A(2017).
  26. Li, W. X., Hao, J. X. and Shuai, L., CN patent, 101376928(2008).
  27. Wada, Y., Fuji, S. and Suzuki, E., "Smelting Magnesium Metal using a Microwave Pidgeon Method," Sci Rep., 7, 46512-46516 (2017). https://doi.org/10.1038/srep46512
  28. Park, S. Y., "Study on Reduction Mechanism for Silicothermic Reduction of Dolomite to Produce Mg(v)," Pohang University of Science and Technology, Pohang, 2011(Master. -Ing. Thesis).
  29. Zhang, M. J., Li, J. D. and Guo, Q. F., "Study of Pidgeon Process Production with Highly Effective Reducing Agent," Light Metals, 12, 39-43(2005).
  30. Xu, D., Zhang, X. P. and Li, G., "Research on Vacuum Thermal Reduction of as Charite with Calcium Carbide as Reductant," Ming Metall., 17(2), 39-42(2008).
  31. Xu, L. M., "Principle and Technical Process of Producing Silicocalcium," Ferro-alloy, 33, 3-8(2008).
  32. Wang, Y. W., Feng, N. X. and Yu, J., "Study on the Effect of CaF2 Addition on the Process of Vacuum Aluminothermic Reduction," Chin. J. Vac. Sci. Technol., 32, 889-895(2012).
  33. Hu, W. X., Liu, J. and Feng, N. X., "The Effect of Villiaumite on Magnesium Production by Al-Si-Fe Alloy Thermal Reduction of Dolomite," Light Metals., 5, 42-48(2010).
  34. Feng, N. X. and Wang, Y. W., "A Method of Producing Magnesium by Vacuum Thermal Reduction Using a Mixture of Magnesite and Dolomite as Materials," Chin. J. Nonferrous Metals., 21, 2678-2682(2011).
  35. Hwang, D. J. and Yu, Y. H., "A Study on Synthesis of CaCO3 & MgO/Mg(OH)2 from Dolomite Using the Strong Acidic Cation Exchange Resin," Korean Chem. Eng. Res, 57(6), 1-14(2019).
  36. Bes, A., "Dynamic Process Simulation of Limestone Calcination in Normal Shaft Kilns," Ottovon-Guericke University Magdeburg, Germany, 2006(Dr.-Ing. Thesis).
  37. Park, D. G., KR patent, 10-2009-0133310(2009).
  38. Park, Y. Y., Hwang, K. S. and Lee, B. K., KR patent, 10-2011-0142242(2011).
  39. Eom, H. S., Park, D. G. and Han, G. S., KR patent, 10-2011-0143667(2011).
  40. Park, D. G., Choi, H. and Kim, D. S., KR patent, 10-2011-0145169(2011).
  41. Han, G. S. and Choi, G. S., KR patent 10-2012-0002771(2011).
  42. Choi, G. S. and Han, G. S., KR patent 10-2012-0002768(2012).
  43. Choi, G. S., Han, G. S. and Kim, M. C., KR patent 10-2012-0002758(2012).
  44. Choi, H., Park, D. G. and Han, S. H., KR patent 10-2011-0143749(2011).
  45. Park, D. G., Kim, H. S., KR patent 10-2009-0133312(2009).
  46. Cho, W. W. and Shi, S. K., KR patent 10-2012-0151285(2012).
  47. Yu, Y. H., Hwang, D. J. and Ahn, Y. J., "A Comparative Study on the Calcination and Hydration of Dolomite Using MicroWave and Electric Furnaces," KSMER, 58(2), 2288-2291(2021).