산업부산물을 이용한 중금속/유기성 슬러지의 고형화 및 용출특성에 관한 연구 = Solidification of Heavy Metal in Sludge by Silica Fume and its Leachability

다국어 초록 (Multilingual Abstract)

This paper discusses the development of mixes for silica fume as stabilization/solidification agents and binders for industrial wastewater residue containing organic and heavy metal contaminants. The UCS(Unconfined Compressive Strength) gradually increased to 66.7% as the silicafume content increased to 15%. The leaching of TOC and chromium decreased as more OPC was substituted with silica fume. When the mix had 5% silica fume, it retained about 85% TOC, and chromium leached out 0.76mg-Cr/g-Cr in acidic solution. Also, microstructural studies of the solidified wastes through the scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and X-ray diffraction analysis showed that the silica fume caused an inhibition to the ettringite formation which did not contribute to setting, but coated the cement particles and retarded the setting reactions. The results indicated that the incorporation of silica fume into the cement matrix minimized the detrimental effects of organic materials on the cement hydration reaction and contaminant leachability.