Heap Leaching for Au/Ag

[kjavanb123]

All,

This is about the copper flotation tailing project I have been working on for quite sometimes now. Head assay indicates 0.2ppm Au and 4.5ppm Ag. At 4Mt reserve of tailing, can we conclude it is feasible to do a heap leaching for Gold and Silver on the tailing dump? Any estimate on how much is the cost per tonnage for heap leaching?

Thanks and happy new yr
Kevin

 

[ander]

0.2ppm-> 0.2g Au/tonne 4Mt= 4000 000 t ->*0,2g-> 0,8t (~1800 pounds).
4.5ppm Ag-> 18tonnes.
at current prices Au worths like... astronomical number. But 0,2g Au is like 7 USD, 4,5g Ag is like 10 USD. So 17 USD per tonne. The content seems very low for gold, but in my country copper mining company makes like 1tonne of gold annually at similar level of concentration.

 

[Juan Manuel Arcos Frank]

Kevin:

Copper mines work like this,they get copper as principal activity and silver,gold and PGM are wastes.

Regards

Manuel

 

[goldsilverpro]

Manuel is right. I once spent a week in the Anaconda tankhouse (2500, 400 gallon tanks, if I remember right). They electrolytically purified a million pounds of copper a day. As a by-product, they collected 30,000 oz of silver and 3,000 oz of gold per month in the anode slimes. Much of the Au and Ag produced comes as a by-product from the primary refining of other metals - copper, lead, etc

 

[Palladium]

I think you are going to have to pick an extraction method or two and field test, field test, field test. Like someone stated earlier in a post about processors i think. You can know exactly what is there in the tailings, but getting what is there out is a whole different story. That's why first you get the assay results from, there you move into trial testing of possible recovery systems, then once that's finalized you can move into full scale operation.

Just knowing how much gold or silver is there is not going to tell you your profit or operating cost. The only way to know them numbers is to test, test, and test. Then plug the numbers.

 

[Anonymous]

All,

Any estimate on how much is the cost per tonnage for heap leaching?
Kevin

How many cubic meters or yards is your tailings pile, to leach out the values you will first have to grade a suitable location that allows runoff, cover the graded area with a liquid proof mat then relocate your tailing onto the mat. Plus a pond to recover your leach, pumps and plumbing to carry the leach for processing,.

I don't think it's going to be cheap by todays hourly rates for trucking and heavy equipment, as you place a layer of tailings onto the mat, it has to be graded before the next layer can be laid down.

In a civilized country each truck load of tailings will have to be tarped, and this applies even if your moving your tailings across the road, you may be required to have a water truck watering the haul roads to keep the dust down.

You need to time how long it take the loader to load 1 truck, time the delivery and return time, then figure how many trucks you'll need to keep the machinery moving efficiently every minute your paying the clock.

To keep the machinery oiled and running proper on your project I would only hire equipment no less than 5 years of age or newer, theres nothing better in life than having to pay a hourly rate for 30 trucks sitting idle because the loader broke down. A mere $1800.00 an hour not counting the dozer sitting at $175.00 an hour.

Just imagine 30 trucks sitting at the side, the drivers all having coffee and smoking god knows what while your paying them $60.00 an hour, not may truckers work by the load these days.

If it were me, I would rent an excavator and dozer for each end of the project, hire truckers who knew how to run said equipment and could read a survey stake to keep the grade proper on your heap pile.

Hopefully you wont have any neighbors to give you opposition in using cyanide. It's claimed that SSN will work well on a heap leach. The Dept of mines may require that you put up an environment deposit or a ( performance bond ) to assure that you will leave the site as good or better than when you began your project.

To many Companies have preceded you in leaching projects only to file bankruptcy on completion, leaving the cost of reclaiming the site to the tax payer.

Unless you have deep pockets, your dreaming.

 

[kjavanb123]

well,

I thought about your posts here, and with today gold prices, 0.5ppm would mean $15 per ton of Gold and 5ppm Ag would mean $2.5 of Ag per metric ton. now if we joint-venture with the copper flotation that has been producing the tailing with above analysis. we can use their loaders or their conveyor belt to remove the tailing to the leaching pad. I am not worried about constant capitals, like the hoses needed for leaching or the tank or refining equipments. the only ongoing cost would be the agent that would drop the gold particles, and the cyanide that is mixed with water. if cyanide + active carbon cost for each ton goes below $15 then this should be profitble assuming we can access all 4 million tons of tailing.

Peace.