基于电解锰渣-磷石膏复合胶凝材料的制备与表征

为了有效提高电解锰渣资源化利用水平,针对电解锰渣化学成分和矿物组成特点,以电解锰渣为主要原料,通过辅加磷石膏、水泥、矿粉制备胶凝材料;在固定矿粉与水泥掺量的基础上,通过改变磷石膏的掺量,研究不同硫酸盐掺量对复合胶凝材料力学性能的影响。研究结果表明,制备的复合胶凝材料中电解锰渣、磷石膏、矿粉、水泥最佳质量配比为50:20:20:10,其硬化体14 d抗压强度可达20.62 MPa,而软化系数为0.80。电解锰渣-磷石膏复合胶凝材料的水化产物主要是钙矾石、C-S-H、和C-A-S-H。水化14 d后的硬化体浸出液中污染物浓度均在《地表水环境质量标准》(GB 3838—2002)中Ⅴ类水体标准的限值内,其中Cr、Cu、Zn、As、Pb、Cd等重金属浓度可达到Ⅰ类水体的标准,硬化体具有良好的环境稳定性。

Preparation and Characterization of Composite Cementitious Material Based on Electrolytic Manganese Residue-Phosphogypsum

In order to effectively improve the resource utilization level of electrolytic manganese residue, according to the chemical composition and mineral composition characteristics of electrolytic manganese residue, the electrolytic manganese residue was used as the main raw material, and the cementitious material was prepared by supplementing phosphogypsum, cement and slag powder. On the basis of fixing the slag and cement content, by changing the content of phosphogypsum, the effect of different sulfate content on the mechanical properties of composite cementitious materials was studied. The research results show that the best quality ratio of electrolytic manganese residue, phosphogypsum, slag powder and cement in the prepared composite cementitious material is 50:20:20:10, and the 14 d compressive strength of the hardened body reaches 20.62 MPa, and the softening coefficient is 0.80. The hydration products of electrolytic manganese residue-phosphogypsum composite cementitious material are mainly ettringite, C-S-H and C-A-S-H. The concentration of pollutants in the leachate of the hardened body after hydration for 14 d is within the limits of the standard of Class V water in the "Surface water environmental quality standard" (GB 3838—2002). The concentration of Cr, Cu, Zn, As, Pb, Cd and other heavy metals can reach the standard of Class I water, and the hardened body has good environmental stability.