Removing Mercury from Tailings

Greetings,

I am an American living in Mindanao Philippines. I am new to mining but have learned a lot from forums such as this one.

I have found some tailing ponds from local small scale miners here that I have assayed and found there is good amounts of gold left in this waste. The problem is almost all the miners here use either mercury or cyanide, and these end up in the tails. As a test I have run small samples of these tails through a popandson sluice and have gotten quite high gold return. My question is: Is there any reasonable way to remove mercury from the tails before I sluice? same question for cyanide?

Thank you in advance

itsnews1

Why try to remove the mercury before you sluice?
It would be far easier to remove it from the cons.

Same with the cyanide, altho, I wouldn't want to work around it.
Randy

I'm a little mystified by the residual cyanide. If there's gold present, wouldn't the cyanide contain values? Wouldn't some mercury be involved in solution as well?

In spite of dissolving large gold particles slowly, as long as cyanide has access to some oxygen, it would dissolve gold until the solution was saturated, or until the gold or cyanide was depleted, assuming it is able to contact the gold. Something isn't making a lot of sense here.

It might be interesting to hear more than you're disclosing.

Harold

Greetings,

Please excuse my ignorance. My concern is the handling of these tailings (around 100 tons). Some of the tailings are from the cyanide/carbon process other talings are from a ball mill mercury process. I have taken around 50 kilos of each and run them through a popandson sluice. I then assayed the concentrate which gave us a more than decent return. I am not a chemist or even an expert with gold mining. I think the big problem here in the PI is these small scale miners are not doing either process correctly. They are loosing gold all over the place because they just do not know the correct chemistry or process for chemical removal. One of my goals it to show how a device like a popandson sluice can replace the current processes they use and deliver a higher return.
My big concern and question is if we (the labor) are handling these tailings are we in danger of harm from the residual chemicals present. If so (I have to believe you would not want to handle this stuff by hand) is there something we can do to treat or make safe these tailings prior to handling. Or maybe another question would be, what is the best way to handle tailings like this?

I figure once I have run 3 or 4 tailing ponds the locals will get the picture that they do not need mercury or cyanide as the popandson is recovering most all the gold that was lost in mercury and/or cyanide processes.

Just an FYI, most miners here recover about 6 to 12 grams (on average) per ton processed using the chems. we are recovering almost this same amount from their tails!! So clearly they are doing something wrong.

Again any suggestions or help is greatly appreciated.

itsnews1

My hunch is that gold is not fully recovered because the ore is not fine enough to permit extraction. It would help to know the nature of the gold and the tailings. You might also consider that the miners are content extracting that which comes easy, leaving the rest. It could be that processing the ore in order to achieve a greater extraction rate would not be cost effective.

I could be wrong. I am not a chemist, nor am I experienced in mining and extraction procedures aside from having processed two small batches of extremely high grade gold----with an extraction of greater than 99%. My process was to run the ore through a ball mill, then to run it in an agitation tank with cyanide and bromine. The slurry was processed through a gasketed filter press, with the values recovered using zinc flour. A less than desirable method of processing unless the ore is high in value.

I am unable to provide any guidance, but ore that has been exposed to cyanide is most likely still poisonous. It might be rendered harmless by the addition of chlorine. I think you'll need Lou's expert advice in this matter.

Harold

have only read of a process,Ore concentrate being crushed fine, drip leached with cyanide, plastic catch basin (recirculated)and where they would use deairator (heat)to rid oxidizers from cyanide before using zink to precipitate values , then would use large retort ovens to remove mercury safely from caked values, then melting to Dore bar,for further refining,I was under the impression they reused the cyanide by reoxidizing it, but this is only a guess.I have no expiereince here,