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Evaluation of Dispersion Characteristics for Liquefied Red Mud by Viscosity and Sediment Index

점도 및 침전지수에 의한 액상화 레드머드의 분산 특성평가

  • Kang, Suk-Pyo (Department of Architecture, Woosuk University) ;
  • Kang, Hye-Ju (Department of Construction Engineering, Woosuk University)
  • Received : 2017.09.27
  • Accepted : 2017.11.23
  • Published : 2017.12.20

Abstract

Red mud is an industrial by-product produced during the manufacturing aluminum hydroxide ($Al(OH)_3$) and aluminum oxide($Al_2O_3$) from Bauxite ores. In Korea, approximately 2 tons of red mud in a sludge form with 50% moisture content is produced when 1ton of $Al_2O_3$ is produced through the Bayer process. In the paper, dispersion characteristics of liquefied red mud that does not require heating and grinding process for recycling were investigated through viscosity and sediment index. The results showed that the sediment index of liquefied red mud increased but viscosity of that decreased with a higher W/R ratio. Also we proposed the range of initial viscosity from 2000cP to 8000cP and target sedimentation index below 20% at elapsed time 180days for stable dispersion of liquefied red mud.

레드머드(Red mud)는 보오크사이트 원광석으로부터 수산화알루미늄($Al(OH)_3$) 및 산화알루미늄($Al_2O_3$)을 제조하는 공정에서 발생되는 산업부산물로 Bayer Process를 통하여 함수율 50%의 슬러지 상태로 국내에서 연간 약 30만톤이 발생되고 있다. 본 논문에서는 함수율 50%의 레드머드 슬러지를 가열 공정없이 건설산업 현장에 사용할 수 있도록 적정 혼합수 및 첨가제를 사용하여 액상화하고 점도, 입도, 침전지수와 같은 분산특성을 검토하였다. 본 논문의 범위에 한정하여 액상화 레드머드의 안정적인 분산을 위해서는 초기 점도를 2000cP에서 8000cP을 적용하고 목표 침전지수를 20%이하로 설정하는 것이 타당할 것으로 사료된다.

Keywords

References

  1. Kim HS. A study of the space planning applying up-cycling resource circulation process [master's thesis]. [Seoul (Korea)]: Sungkyunkwan University; 2017. 121 p.
  2. Pontikes Y, Angelopoulos GN. Bauxite residue in cement and cementitious applications : Current status and a possible way forward, Resources. Conservation and Recycling. 2013 Apr;73(8):53-63. https://doi.org/10.1016/j.resconrec.2013.01.005
  3. Daniel VR, Joao AL, Marcio RM. Potential use of natural red mud as pozzolan for portland cement. Materials Research. 2011 Jan;14(1):60-6. https://doi.org/10.1590/S1516-14392011005000001
  4. Kang SP, Kwon SJ. Effects of red mud and alkali-activated slag cement on efflorescence in cement mortar. Construction and Building Materials. 2017 Feb;133:459-67. https://doi.org/10.1016/j.conbuildmat.2016.12.123
  5. Pan Z, Cheng L, Lu Y, Yang N. Hydration products of alkali-activated slag-red mud cementitious material. Cement and Concrete Research. 2002 Sep;32(3):357-62. https://doi.org/10.1016/S0008-8846(01)00683-4
  6. Kang SP, Kang HJ. Pore and efflorescence characteristics of alkali activated slag-red mud cement mortar depending on red mud. Journal of Korea Institute of Building Construction. 2017 Jan;17(3):261-8. https://doi.org/10.5345/JKIBC.2017.17.3.261
  7. Chu YS, Park YA, Lee HJ. An Experimental study on flocculation and settling of fine-grained suspended sediments. Journal of the Korea Society of Oceanography. 1999 Feb;4(1):40-9.
  8. Myeonggyu Sang, Analysis of sludge settling characteristics in sbr(sequencing batch reactor) process [master's thesis]. [Seoul (Korea)]: University of Seoul; 2008. 64 p.