The gold bearing waste treatment process is as follows:
Grinding is done in preparation for hydrometallurgical or pyrometallurgical. By magnetic screening, magnetic portions are usually removed, the non-magnetic fraction containing significant gold and silver. The precious metal magnetic portion of the losses.
Electronic waste calcination to remove volatile components after ash melting, copper-precious metal into the ingot, which can handle a large number of all kinds of waste, the recovery rate is very high, in this way the output of copper ingots, then standard electrolytic recovery of copper refining process Finally, copper anode mud from precious metals, recovered from the calcination process is to mature, but the disadvantage of this method is to process equipment, especially the large investment in pollution control equipment requirements.
In the low temperature of about 475 ℃, slightly oxidizing atmosphere firing precious metal scrap from the burner out of the smoke and fumes use 100% excess air in the combustion chamber at the back of the 920 ℃ combustion, to ensure that all volatiles complete oxidation. From the rear of the combustion chamber is cooled by air, dust collected in the dust collector. When burning, the typical weight loss of about 30% of electronic waste. In the combustion process should pay attention to stir, to avoid the fire. After the smoke cleared combustion of iron and aluminum, and recovered.
From out of the calciner dust and soda, borax together in a rotary kiln or reflection furnace smelting. Based on the composition of smoke filling quartz fluorite or saltpeter flux. The purpose of the flux is dissolved in a non-metallic components of soot in high-temperature chemical reaction to form slag, the elements do not want to take away. Smelting furnace atmosphere neutral (if there is iron, for the slightly oxidizing atmosphere). After smelting furnace temperature of about 1149 ℃, the charge is discharged. When the metal slag and slag Cuiqu water samples. According to the analysis results to determine remelting or discarded. Copper-based copper ingots intended for refining, smelting furnace flue gas is cooled by the return of collected dust.
From the converter out of the ingot is not suitable to do the refining of copper anode plate. By pyrometallurgical refining, improving ingot quality, but also the incorporation of the former anode plate cast copper ingots and other electronic scrap. During the electrolytic refining of copper so that the precious metal into the anode mud from the first cell anode slime leaching out of the base metal was removed, and then output smelting alloy, an alloy mainly consisting of silver, using conventional electrolytic silver recovery method of silver, that the use of nitrate – nitrate copper – electric nitric acid medium. Gold and silver recovery of platinum group elements from the cell anode mud.