某金银矿石浮选——氰化联合流程选矿试验

Experimental Study on Flotation——cyanide Combined Process of a Gold-silver Ore

某金银矿石含金4.80 g/t,含银565 g/t,金矿物主要为自然金,呈独立矿物形式存在,部分以显微或次显微状赋存于褐铁矿及石英中,裸露金占总金的72.29%,铁矿物和硅酸盐矿物包裹金分别占总金的22.08%和5.63%;银矿物主要以辉银矿形式存在,嵌布粒度较粗,硫化银占总银的91.33%,自然银和氯化银含量较低,分别仅占总银的6.55%和2.12%。为实现该金银矿的高效开发利用,进行了选矿试验。结果表明:矿石在磨矿细度为-0.074 mm占74.5%的情况下,采用1粗4精2扫、精选1尾矿精扫选后再返回的浮选流程处理,可获得金品位为77.19 g/t、银品位为11302 g/t,金、银回收率分别为75.58%和94.02%的精矿;金、银品位分别为1.23 g/t和35.45 g/t的浮选尾矿在再磨细度为-0.043 mm占86%的情况下氰化浸出,浸渣金、银品位分别为0.10 g/t和17.88 g/t,金、银对浮选尾矿的浸出率分别为91.87%和49.56%,全流程金、银总回收率分别达98.01%和96.98%。

A gold-silver ore contains gold 4.80 g/t and silver 565 g/t.The gold mineral is mainly native gold,which exists as the form of independent mineral.Some parts are in the form of microscopy or submicroscopy disseminated in limonite and quartz.Bare gold accounts for 72.29%of total gold,and gold wrapped in iron minerals and silicate minerals account for 22.08%and 5.63%of total gold,respectively;silver minerals mainly exist in the form of argentite with coarser grain size,and silver sulfide accounts for 91.33%of total silver.The contents of native silver and silver chloride are low,which account for only 6.55%and 2.12%of total silver,respectively.In order to realize the high-efficient exploitation and utilization of the gold-silver ores,flotation tests were carried out.The results showed that when the ore fineness is-0.074 mm 74.5%,concentrate with gold grade of 77.19 g/t,gold recovery of 75.58%,silver grade of 11302 g/t,and silver recovery of 94.02%was obtained by using the one coarse four cleaning two sweeping,the tailing cleaning for one time returning to the flotation process after sweeping;The cyanidation leaching was carried out with the tailing which gold grade is of 1.23 g/t,silver grade is of 35.45 g/t and a regrinding fineness is of-0.043 mm 86%.The grades of leaching residue are gold 0.10 g/t and silver 17.88 g/t,respectively,and the leaching rates of gold and silver for flotation tailings were 91.87%and 49.56%,respectively.The total recovery rate of gold and silver in the whole process reached 98.01%and 96.98%,respectively.