全固废胶凝材料固化铅的试验研究

Stabilization of Pb^(2+) by Cementitious Materials Prepared with All Solid Waste

以钢渣、矿渣和脱硫石膏为原料制备胶凝材料,研究了胶凝材料组成和铅离子质量浓度对胶凝材料固铅效果的影响,并利用XRD、TG-DSC和SEM对固铅胶凝材料的水化产物进行分析。结果表明,在钢渣掺量不超过30%,铅离子质量分数不高于0.5%时,胶凝材料固铅试样28 d龄期铅浸出质量浓度低于地下水环境质量标准(GB/T 14848-93)Ⅲ类水0.05 mg/L的限值。XRD、TG-DSC和SEM分析结果表明,全固废胶凝材料试样中不仅钙矾石含量较高,硅氧四面体链接也较为复杂,存在类沸石相结构,这是其固铅性能好的原因。

Cementitious materials was prepared with steel slag powder（SS）, blast furnace slag（BFS） and desulfurization gypsum（DG）. The effect of the composition and concentration of lead ions on the lead fixation were studied. The hydration products of Lead-containing cementitious materials was analyzed by X-ray diffraction（XRD）, thermogravimetric-differential scanning calorimetry（TG-DSC） and scanning electron microscope（SEM）. The results showed that the quantities of Pb2＋ leached from the lead-containing cementitious materials aged for 28 d are below 0.05 mg/L which is the threshold value of Pb2＋ concentration for Type ground water in Chinese quality standard for ground water GB/T 14848-93, when the steel slag content is less than 30%. XRD, TG-DSC and SEM spectroscopy analysis results showed that there are not only much more ettringite, but also the siloxane tetrahedral link is more complex complex, and exist zeolite phase structure, which is the reason for good lead solidification performance.