采用二氰胺钠浸出某金矿石试验研究

Leaching Experiment on a Gold Ore with Sodium Dicyanamide

针对传统氰化钠浸金工艺严重污染环境的弊端,以二氰胺钠为浸金剂,对加拿大某金品位为3.39 g/t的金矿石进行浸出试验。结果表明:矿石磨细至-45μm占75%,在700℃焙烧1 h后,获得的焙砂在二氰胺钠用量8kg/t、过氧化氢用量1.2 mL、矿浆p H=11.5、液固比4 m L/g、浸出温度35℃、浸出时间24 h的条件下,可获得金浸出率为89.08%、浸渣金品位0.38 g/t的指标,二氰胺钠的浸金效果良好。并且该浸金体系的总氰化物含量远低于国家环保排放标准。因此,二氰胺钠作为一种高效低毒的金矿浸出剂,具有一定的应用前景。

In view of the serious environmental pollution caused by the traditional gold leaching process with sodium cyanide, sodium dicyandiamide was used as gold leaching agent to effectively treat a quartz vein gold ore with 3.39 g/t gold from Canada. The results indicated that, at the grinding fineness of 75% passing 45 μm, roasting 1 h at 700 ℃, the roasted products with sodium dicyandiamide dosage of 8 kg/t, hydrogen peroxide1.2 mL, pulp pH=11.5, liquid-solid ratio 4 mL/g, leaching temperature of 35 ℃ for 24 h, gold leaching rate is 89.08%, and the gold grade of leaching residual is 0.38 g/t. Using sodium dicyandiamide as leaching reagents can obtain good leaching results. The total cyanide content in the leaching system is far below the national environmental protection discharge standard. Therefore, sodium dicyandiamide as a high-efficiency and low-toxicity gold ore leaching agent has a certain application prospect.