Experimental study on complex precipitation-sulfide precipitation joint treatment of copper cyanide barren solution
In response to the copper cyanide barren solution generated by a gold production company,a joint recovery treatment using complex precipitation and sulfide precipitation was adopted.Under the conditions of adding 3.0 g/L of copper sulfate pentahydrate and 2.0 g/L of sodium metabisulfite in the complex precipitation process,and adding 0.35 g/L of sodium sulfide nonahydrate in the sulfide precipitation process,the mass concentrations of total cyanide compounds,copper,and thiocyanate in the copper cyanide barren solution decreased from 150.84 mg/L,121.46 mg/L,252.65 mg/L to 0.44 mg/L,86.17 mg/L,1.23 mg/L,respectively.The production value of gold,silver,and copper recovery was 116.62 yuan/m3,generating an economic benefit of 55.44 yuan/m3 after deducting the cost of reagents.The research results provide a reference for the purification treatment of similar cyanide barren solutions in cyanide enterprises.