Chemical composition of concentrate, %  Flotation concentrate Re-election concentrate  ( 93%- ( 55%- SiO 2 23.2 2.22 Al 2 O 3 7.28 0.3 Fe 2 O 3 27.3 57.3 TiO 2 0.8 0.4 MgO 0.4 0.3 CaO 0.84 0.84 MnO 0.03 0.08 K 2 O 1.7 0.1 Na 2 O 0.5 0.1 S gold 18.8 33.4 Ss 18.0 32.7 C organic 11.5 0.47 Cu 0.11 0.05 Zn 0.58 0.2 Ph 0.8 4.4 As 7.5 19.6 28.5 56.5 FeA s S 17.9 32.8 Due to the content of activated carbon in flotation concentrates, it is more difficult to recover precious metals by direct cyanidation. The gold recovery rate can only reach 12.9% and the silver recovery rate is 12.8%. 31GSM Fast Dry Sublimation Paper 31Gsm Fast Dry Sublimation Paper,Inkjet Heat Transfer Paper Roll,Inkjet Heat Transfer Paper Rolls,Inkjet Heat Transfer Paper Suzhou Hummberg Paper CO.,LTD , https://www.humpaper.com
This paper describes the comparison of carbon-containing gold- silver -shen concentrates (flotation concentrates and re-concentrated concentrates) with different compositions according to the following joint process: oxidative roasting---calcination for immersion; galvanic oxidation Leaching-leaching slag for adsorption cyanidation; bacterial leaching---leaching slag for adsorption cyanidation. At the same time, the effect of the treatment method of concentrate on the adsorption activity was also studied.
The concentrate used in the study was obtained by sorting the fine-disseminated gold-silver sulfide ore according to the re-election-flotation process. In the sorting process, 75.9% of the gold enriched in the re-concentrated concentrate was 75.5% in the flotation concentrate.
When the re-elected concentrate containing 0.47% of organic carbon is treated by direct cyanidation, a higher metal recovery rate is obtained: gold is 48.1% and silver is 80%. From the phase analysis of re-elastic concentrates and flotation concentrates with a grinding fineness of 93%---0.044 mm,
The precious metals recoverable from the above concentrates by cyanidation (addition of 10% AM-2B anion exchange resin) were: 54.3% and 40.9% of gold, and 84.1% and 63.2% of silver, respectively.
Three-stage cyanidation of the flotation concentrate, the cyanide solution and resin must be replaced in each section. With the gold recovery rate (41%) unchanged, the silver recovery rate can be increased from 63.2% to 86.1%. It has been demonstrated, can not be recovered by cyanidation of gold mainly pyrite and arsenopyrite symbiosis, only a small amount of gold (2-3%) of fine particles present in the quartz disseminated. Concentrate mainly simple silver sulfide (sulfur spiro silver) and sulfonates (Au copper and silver sulfur antimony ore), mainly contained in reselection sulfur concentrate spiro silver, floats The concentrate is mainly composed of sulfonate. This is the reason for the silver recovery rate when performing adsorption cyanidation. The above indicates that other very formal methods must be used to deal with such concentrates.
This type of concentrate can be used in a muffle furnace for two, two and three stages of roasting. The calcination temperatures are 500 to 550 ° C, 600 to 650 ° C and 850 ° C, respectively. Each firing time was 2 hours.
For the autoclave oxidative leaching experiment, a machine-stirred titanium autoclave developed by Vishnevsky was used with a volume of 1 liter. The partial pressure of oxygen at each experiment was 1 MPa. The slurry solids ratio is maintained at 4:1. The fineness of the concentrate is 93~95%--0.044 mm, the temperature is 160oC and 180oC, and the oxidation time is 1.5 and 3 hours.
Treatment method of carbon-containing gold-silver-arsenic concentrate (1)
When dealing with refractory gold concentrates containing sulphide-impregnated gold in sulphide, it is recommended to use hydrometallurgy or pyrometallurgy, as well as a combined process including wet and fire methods.