Plate frame filter press is general tool for hydrometallurgy. For gold mine, normally it adopts cyanidation. As we know, the chemical properties of gold are very stable, but it has a characteristic: if it is put into the water solution of potassium cyanide (sodium), and then the gold will become a soluble cyanide. Then the suspend will be filtered by plate frame filter press. The rule of gold cyanidation is to use cyanide as a leaching solution to extract gold. Cyanidation is the main method to extract gold from gold bearing minerals. For gold tailing and gold concentrate, plate frame filter press is a typical method.
Specifically speaking, according to the good floatability, flotation is used to separate gold and other impurities. Then, cyanidation is used. It is based on the ability to react with cyanide to form soluble salts. The solution rich in cyanide gold is called pregnant solution, and the solution with less useful components is called barren solution. The pregnant solution can be replaced with zinc powder under acidic conditions, and then smelted and electrolyzed, and finally the gold with higher purity can be obtained. Plate frame filter press is used after this step. The basic process is: flotation can produces gold concentrate, then re-regrind by the ball mill, cyanide leaching, back washing, and then solid-liquid separating by plate frame filter press machine. After the plate filter press, the zinc powder is added in the pregnant solution, then it will get gold mud by replacement reaction. Then the gold mud is smelted in the smelting chamber. Finally, the electrolysis of combined gold will product gold ingot, and by-product sulphur concentrate.
We know cyanidation is most popular for gold mining, because of low cost and good performance. However, it’s huge toxic, thus will cause lots of harmful wastewater. So recent year, the engineers pays attention again on chlorination process. No matter cyanidation or chlorination process, they are belongs to hydrometallurgy, so our plate frame filter press are also perfectly suitable for the both.