基于矿冶废渣制备充填专用胶凝材料研究

本文首先测定了矿冶废渣及原材料的基本化学性质,并根据测试结果研发了复合型强碱性激发剂,用于激发矿冶废渣活性,从而制备出适用于矿山充填专用胶凝材料；通过XRD测试了充填专用胶凝材料硬化体中的水化反应产物,结果表明支撑充填体强度的主要物质为钙矾石(AFt)和氢氧化钙(CH)、铝胶(AH_8-10)、水化硅酸钙(C-S-H)、水化硅铝酸钙(C-A-S-H)等。一个钙矾石(AFt)分子形成会结合和吸附32个H₂O分子,表明矿山充填专用胶凝材料更适合含水量较大的尾砂充填料浆。同时采用SEM分析了不同龄期充填硬化体内部结构,揭露了充填硬化体强度增长规律,并分析了各阶段硬化体产生强度的机理；通过强度试验测试了不同条件下两种胶凝材料充填体强度,结果表明充填专用胶凝材料(KS)制备的充填体强度指标高于水泥(SN)制备的充填体强度,强度值相差1倍。

Study on preparation of backfill cementitious material based on mining and metallurgical waste

In this paper, the basic chemical properties of mining and metallurgical waste slag and raw materials are measured, and compound strong alkaline activator is developed according to the test results, which can be used to activate the activity of mining and metallurgical waste slag, so as to prepare special backfill cementitious material. The hydration reaction products in the backfill were tested by XRD. The results showed that the main hydration products supporting the strength of backfill were ettringite (AFt), calcium hydroxide (CH), aluminum glue (AH_8-10), calcium silicate hydrate (C-S-H), hydrated calcium aluminosilicate (C-A-S-H), etc. The formation of one ettringite (AFt) molecule will bind and adsorb 32 H₂O molecules, indicating that the special backfill cementitious material is more suitable for backfill slurry with larger water content. At the same time, SEM was used to analyze the internal structure of the backfill at different ages, revealing the strength growth law of the backfill, and analyzing the strength mechanism of the backfill at each stage. The strength of backfill of two kinds of cementitious materials was tested by strength test under different conditions. The results showed that the strength of backfill prepared by special cementitious materials (KS) was higher than that prepared by cement (SN), and the strength was 1 times different.