FORC5 <[EMAIL PROTECTED]> wrote: > gold recovery, I wonder how this is done and if it is worth it ?.
In the early eighties, I remodeled a good size, two story building called The Miami Postal Credit Union into a gold and silver recovery and refining plant for a company called IMC, Intercontinental Medals Corp. I stayed on for almost a year as plant manager. The had some new methods of refining that worked well in the lab, but not so great in full scale practice. We made a lot of changes to the machinery to get it to work. Here are some pix from PR Press Day. We were not allowed to take pix of our own. All pix are staged, this is before we really got into production. These are from the official brochure. Sorry, the pix are a little bad because the brochure went through hurricane Andrew, '92. One was the main kiln. It was used for the bilk work; separating most of the impurities from the precious metal. It had doors on the side that when opened, set the walls on fire, even with protective material on the walls. Me with a brand new heat suit: http://al_anger.home.comcast.net/gold/kiln1.jpg The object in front of the kiln is for poring the crucibles with; they get locked into the ring. Next, with the doors open: http://al_anger.home.comcast.net/gold/kiln2.jpg The kiln wasn't hot that day. I welded the doors shut, cut the top off the kiln and made a roiling top that slid to one side. Also a vent to collect the heat when open, and blow it outside. This unit was for the finish refining: http://al_anger.home.comcast.net/gold/kiln3.jpg What you see is the finish end of the kiln. http://al_anger.home.comcast.net/gold/kiln4.jpg These white trays were loaded with the ~90% refined metal, and placed in the kiln. Cleaning flux is added through a hole in the top and the flux is scraped off at regular intervals; until the metal reaches .999. Then the tray is pulled to the finish half of the kiln (kiln3.jpg) with the upper crank handle. (with the wire sloppily wound around it) Then the lower crank handle tilts the tray to pore the molten metal into the ingot molds. All this is done in an argon atmosphere. The ingots are allowed to cool till solid in the argon gas. We spent months working out the bugs in this design. (that's me - without the hard hat) I only have one pic of the electro-deplating room: http://al_anger.home.comcast.net/gold/electro.jpg Similar to fries cooked in oil at MickyD's The scrap is lowered into a cyanide bath and de-plated onto plates hung from the rods. You can see two of the rods in the upper position. The cyanide bath has to be kept at exactly the right pH or everyone in the room drops over. :( There were sensors to detect any cyanide in the air. On the roof of the building I installed giant scrubbers to clean all of the air coming from the plant: http://al_anger.home.comcast.net/gold/clean.jpg Here are some shots of me in the assay lab, testing for potential precious metal in the raw scrap: http://al_anger.home.comcast.net/gold/lab.jpg and http://al_anger.home.comcast.net/gold/lab2.jpg any questions? best, al
