陕西某难处理金矿预处理—浸出试验研究

Experimental Study on Pretreatment-Leaching Process of a Refractory Gold Ore in Shaanxi

针对陕西山阳某难处理金矿中硫化物包裹金及碳质物"劫金"现象导致金浸出率低的问题,使用二氧化氯作为氧化剂,实验室自制复配表面活性剂DS-1作为碳质物抑制剂,DS-5作为浸出剂对该难处理金矿进行预处理—浸出条件试验。结果表明:在磨矿细度-23μm含量80%,使用二氧化氯0.6 kg/t预氧化1 h,预氧化后试样在碳质物抑制剂DS-1用量4.5 kg/t、碳质物抑制预处理时间0.5 h、预处理温度30℃条件下进行碳质物抑制预处理,预处理后矿样在浸金药剂DS-5用量为5 kg/t,矿浆pH=11.08,液固比3 mL/g以及浸出时间48 h的条件下浸出,最终金的浸出率为49.30%,相比于原矿在该条件下直接浸出的浸出率9.29%提高了40.01个百分点。

With conventional cyanide leaching techniques,the leaching rate of the refractory gold ore from Shanyang in Shaanxi Province is extremely low due to the cover of gold by sulfides and the"preg-robbing"by carbonaceous matter.To liminate these effects thus improve the leaching rate,the process of chlorine dioxide oxidation pretreatment-inhibition of carbonaceous matter-leaching was proposed.The condition experiments were carried out with DS-1 as the inhibitor of carbonaceous matter and DS-5 as the leaching agent.Results indicated that with the grinding fineness of 80%-23μm,the overall gold leaching rate is 49.30%under the following conditions:1 h oxidation pretreatment at 30℃with 0.6 kg/t chlorine dioxide,0.5 h inhibition treatment with 4.5 kg/t DS-1,followed by 48 h leaching with 5 kg/t DS-5 and liquid-solid ratio of 3 mL/g at pH 11.08.With the process,the leaching rate has increased from initial direct cyanide leaching technique of 9.29%relative to that of 40.01 percentage points at the comparative conditions.