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Mercury in gold processing

2018/5/22      view:
   In cases of Mercury contaminated tailings, Mercury is actually your friend and helps you recover gold that could not be recovered by physical concentration methods! Mercury processing (Amalgamation) is a chemical process for recovery of Gold and is very effective for the recovery of large to micron gold particles. It’s a fact, that ALL Mercury process’s ever used in the past and present lose Mercury & Gold to the tailings, especially with milled hard rock tailings. The reason for Mercury loss, is during processing the Mercury is agitated by the process equipment, ore and dirty water and naturally and very easily split’s into very small particles known as global’ s, (tiny spheres). This results is called flouring of the Mercury, these global’ s can split (breaking down) so fine it becomes near colloidal in water and are near impossible to recover. Thankfully, most processors are aware of this fact and take measures to reduce the flouring effect, however some mercury is always lost, how much depends on the processor and process. It’s also proven Mercury loss’s from mining operations contain fine to sub-micron gold particles encapsulated in the Mercury. Recovering the Mercury recovers these Gold values  and can result in a very profitable venture, along with an added positive environmental effect by taking the Mercury out of the environment! 
 
   Jinchuan’s has Mercury/Gold recovery technologies that makes it very easy for the user to recover all (99%) of the Mercury & Gold contained in the tailings. During the Jinchuan Mercury/Gold recovery process it captures the flour Mercury and re-amalgamates into a easily recoverable size. It’s not magic it’s just common sense, good equipment and experience!
 
  Both, Jinchuan’s Centrifuge and Multi-Helix Spiral Concentrators are excellent for Mercury recovery from tailings projects. With fine milled tailings or virtually any Mercury contaminated tailings, the Centrifuge is recommended as the primary concentrator. The Centrifuge is a centrifugal concentrator and has a greater chance for recovery of all sub-micron Mercury partials that float in the process water and could escape in the water from a gravity concentrator. Mercury is the only liquid metal known to man and no matter what it’s particle size, it’s malleable. When hit by the centrifugal forces the malleability of the mercury will take any shape allowing it to penetrate the concentrate bed and work its way to the inner walls of the centrifuge, where it will stay trapped and protected until the operator wishes to recover it from the concentrator. The Centrifuge is a batch concentrator, meaning it will retain the Mercury inside it’s concentrate chambers. To recover the mercury the user just slows down the centrifuge and the Mercury/Gold will discharge. This discharge has a very high Mercury content and is mixed with heavy minerals such as black sands. The user needs to take grate care with handling the concentrate, so no further contamination takes place.  For secondary recovery a Spiral Cleaner is used to process the Mercury concentrate. Depending on the amount of mercury in the concentrate material depends if a Multi-Helix Spiral is Finisher will be required. The more Mercury the material the easier it is to recover. Reason being, the Mercury re-amalgamates back into a liquid form in the concentrator and is easily separated from the sands.
 
   When the Mercury is recovered from the concentration circuit. It is filtered through a special 1mu Mercury pressure filter, where the liquid Mercury is separated from the Gold amalgam. The Gold amalgam is 50/50 by weight Gold & Mercury. The amalgam is then placed into a Mercury Retort, where the mercury is safely retorted (vaporized) and re-condensed into a clean gold free liquid. The now Mercury free gold is ready for smelting into a gold bar