This is what I have set up...
I have a 110 tank with AP, I have long ceramic air stones pushing air into the bottom of the tank. I am using submersible pumps, I had to remove the axle and coat with plastic before using, I check them each day for corrosion and have seen none as of yet, these are used at the 4 corners to keep the solution moving in a circular pattern through the tank. I have a gravity filter set up to pass through a polypropylene sponge (thank you Lou), this captures the larger gold foils. It is then fed into a 30 gallon reef tank filter that is also made of Plexi. This has a acid resistant pump that sucks the solution through a series of three poly filters. I have yet to see any gold in the third filter, but the first two do collect a lot of finer gold foil. The Copper II Chloride is then pumped back into the tank by the acid pump, where it is pushed into the tank from the surface so that it introduces more oxygen into the solution, and keeps the solution moving around in the tank.
When the filters become so saturated that it makes a difference in the GPH I am moving, I shut off the pumps, remove the poly sponge filters/felt filters, and replace them with new ones. I then put the poly filters in a reaction vessel with AR. They come out totally white again and ready to replace the pregnant filters in the AP tank. It works amazingly well. I am thinking about making one for a sulfuric cell as well so it can be used continuously without having to stop, settle, filter before you can continue to process. But this will be far more involved, and take learning a few new tricks to make it work I think. But for AP, it is working great so far.
I am using plastic clips with poly cord that hang from two long plastic pips above. This allows me to clip onto whatever it is I am foiling gold off of. I put the material in the left side of the tank, and as I remove the ones from the right side, I move the material down ever closer to the right side of the tank. This allows the material to be hit by the circulating AP at different points. By the time it makes it to the right hand side it is totally stripped.
The only consumable (cost) is in electricity, I am planning on hooking it up to solar cells in the future so that it will not cost anything to operate at all.
I am in the process of moving, so the tank is coming apart soon. I am going to siphon from the tank into 55 gallon barrels already set up in a truck, then do the same to put it back in the tank once I move. When I get it all set up again I'll take pictures and video. The system works really well, I do have a little crazing on the plexi itself, but it's nothing I haven't seen before in some of my salt tanks, and it hasn't weakened the structural integrity of the tank at all.
Scott
