Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
권호 표지

Leaching and stabilization of the heavy metals with pH in EAF dust-clay system

EAF 더스트-점토계의 중금속 용출 및 안정화에 미치는 pH의 영향

  • Lee, Jee-Young (Department of Materials Engineering, Kyonggi University) ;
  • Lee, Ki-Gang (Department of Materials Engineering, Kyonggi University) ;
  • Kim, Yoo-Taek (Department of Materials Engineering, Kyonggi University) ;
  • Kang, Seung-Gu (Department of Materials Engineering, Kyonggi University) ;
  • Kim, Jung-Hwan (Department of Materials Engineering, Kyonggi University)
  • Published : 2006.04.30
Download PDF
⟨ Previous Next ⟩

Abstract

To recycle the electric arc furnace (EAF) dust as a ceramic raw materials, the leaching concentrations of heavy metals (Zn, Pb, Cr, Cd) were analysed with various pH and mixing ratios for EAF dust and EAF dust-clay mixtures. The evaporation amounts of the some heavy metals were evaluated by measuring their total concentrations in the sintered bodies of EAF dust-clay mixtures with various mixing ratio and sintering temperature. Toxicity characteristic leaching procedure (TCLP) test was conducted for evaluating the chemical stabilities of the heavy metal elements. Leaching concentrations of heavy metal ions shows minimum leaching concentration at the pH 10. Evaporation amount of heavy metals in the sintered bodies were evaluated for the mixtures of pH 10 depenidng on mixing ratio and sintering temperature. Evaporation of heavy metal components were increased with increasing the sintering temperature and contents of the EAF dust. The evaporation of the heavy metal components in EAF dust was effectively suppressed by increasing the clay content. The leaching concentrations of heavy metal components were decreased with increasing clay content and temperature.

유해한 중금속을 다량 함유하는 EAF(electric arc furnace) 더스트를 세라믹 원료로 재활용하기 위해서 EAF 더스트, EAF 더스트-점토에 대해서 pH와 혼합비에 따른 중금속 용출농도의 변화를 분석하였다. 소성과정 중에서 발생하는 중금속의 휘발량을 소지 내의 중금속 이온의 총량을 측정하여 평가하였으며 TCLP(toxicity characteristic leaching procedure)분석을 통해 중금속 이온의 안정화 정도를 평가하였다. EAF 더스트-점토 슬러리의 pH를 10으로 조절하였을 경우에 습식혼합 여액중의 중금속 이온의 농도가 가장 낮은 값을 가졌다. pH 10의 슬러리에 대해서 혼합비와 소성온도에 따른 소지내 중금속 이온의 총량을 측정한 결과 소성온도와 EAF 더스트의 함량이 증가할수록 중금속의 휘발이 증가하였으며, 점토의 혼합비가 증가할수록 중금속 이온의 휘발이 억제되었다. TCLP 분석결과 점토의 혼합비와 소성온도가 증가할수록 중금속의 용출은 감소하였으며 중금속의 용출농도는 기준치 이하로 안정화되었음을 확인할 수 있었다.

Keywords

References

  1. J.R. Conner and S.L. Hoeffner, 'Critical review of stabilization/solidification technology', Crit. Rev. Environ. Sci. Technol. 28(4) (1998) 397 https://doi.org/10.1080/10643389891254250
  2. Y.-H. Lee and J.-H. Lee, 'The Behaviors of Zinc lead and chlorine in the pyrometallurgical process for electric arc furnace steel dust', J. of the Korean Inst. of Met. & Nater. 35(9) (1997) 1190
  3. K.-H. Hong, S.-K. Park and N.-W. Lim, 'Leaching caracteristrics of the heavy metals contained the EAF dust, after fixed with OPC', J. of the Korea Society for Environmental Analysis 1(2) (1998) 149
  4. J.-S. Hwang, C.-H. Oh and C.-T. Lee, 'Leaching of valuable metal and separation of Zn component from the solid waste EAF dust', J. Kor. Solid Wastes Engineering Society 13(1) (1996) 96
  5. E.A. Dominguez and R. Ullmann 'Ecoligical bricks made with clays and steel dust pollutants', Applied Clay Science 11 (1996) 237 https://doi.org/10.1016/S0169-1317(96)00020-8
  6. T.H. Um, Y. Kim, K.G. Lee, S.G. Kang and J.H. Kim, 'Microstructural analysis of sintered brick made of recycled wastes', J. Kor. Cryst. Growth and Cryst. Tech. 13(4) (2003) 199
  7. S.A. Mikhail, A.M. Turcotte and J. Aota, 'Thermoanalytical study of EAF dust and its vitrification product', Thermochimica Acta 287, 71 (1996) 71 https://doi.org/10.1016/0040-6031(96)02990-5
  8. J.H. Kim, K.G. Lee, Y.T. Kim and S.K. Kang, 'Thermal and leaching behaviors of EAF dust-clay systems', Mat. Sci. Forum Vols. (2005) 486
  9. W.J. Bruckard, K.J. Daveya, T. Rodopoulosa, J.T. Woodcocka and J. Italianob, 'Water leaching and magnetic separation for decreasing the chloride level and upgrading the zinc content of EAF steelmaking baghouse dusts', Int. J. Miner. Process. 75 (2005) 1 https://doi.org/10.1016/j.minpro.2004.04.007
  10. K.S. Choi, 'Removal of heavy metal ions from wastewater by ion exchange', J. of KSEE 10(2) (1988) 25
  11. Y. Kim, J.H. Kim, K.G. Lee and S.G. Kang, 'Adsorption behavior of heavy metal ions in the solutions of clay minerals undervarious conditions', J. of Cer. Pro. Res. 6(1) (2005) 25
  12. J.-S. Kim, J.-R. Lee, S.-W. Han, I.-G. Hwang and J.-H. Bae, 'Preparation of inorganic coagulants using red mud', J. of KSEE 22(11) (2000) 2085
  13. Bae Hae R. and Cho Soon H., 'Solidification of heavy metal wastes using clay', J. of KSEE 14(3) (1992) 233
  14. M.A. Sorensen, E.P.B. Mogensen, K. Lundtorp, D.L. Jensen and T.H. Christensen, 'High temperature cotreatment of bottom ash and stabilized fly ashes from waste incineration', Waste Management 21 (2001) 555 https://doi.org/10.1016/S0956-053X(00)00113-6