How to refine mining dore bar that content 15% silver by using aqua regia?

[Phoebe]

We would like to express our gratitude for the valuable comments provided in the forum; they have been incredibly helpful.

As gold traders who ventured into the refinery business a year ago, we currently have a daily capacity of refining 30kg using Aqua Regia (AR) as our primary method.

Throughout this period, we have successfully carried out the refinery process with less than 7% silver content. However, we recently received a new order to refine a mining dore bar weighing approximately 30-40kg per week, with a silver content of 15%. Given the high percentage of silver, we have encountered difficulties using AR as it is unable to remove the overlay 'coating,' resulting in a loss of nearly 0.3%.

While inquartation is a stable and consistent approach, we are hesitant to utilize it due to the additional costs involved in purchasing a few kilograms of silver, the need for an additional refining process to recover the silver, and the potential impact on our work capacity caused by the time required for these additional steps.

Our primary intention in asking this question here is to seek advice from experts regarding alternatives to Aqua Regia. We are searching for methods that can provide us with the optimum amount of gold without incurring excessive costs or consuming too much time.

By the way, I'm a 'she' not He. Haha

 

[Yggdrasil]

We would like to express our gratitude for the valuable comments provided in the forum; they have been incredibly helpful.

As gold traders who ventured into the refinery business a year ago, we currently have a daily capacity of refining 30kg using Aqua Regia (AR) as our primary method.

Throughout this period, we have successfully carried out the refinery process with less than 7% silver content. However, we recently received a new order to refine a mining dore bar weighing approximately 30-40kg per week, with a silver content of 15%. Given the high percentage of silver, we have encountered difficulties using AR as it is unable to remove the overlay 'coating,' resulting in a loss of nearly 0.3%.

While inquartation is a stable and consistent approach, we are hesitant to utilize it due to the additional costs involved in purchasing a few kilograms of silver, the need for an additional refining process to recover the silver, and the potential impact on our work capacity caused by the time required for these additional steps.

Our primary intention in asking this question here is to seek advice from experts regarding alternatives to Aqua Regia. We are searching for methods that can provide us with the optimum amount of gold without incurring excessive costs or consuming too much time.

By the way, I'm a 'she' not He. Haha

Process wise, nothing beats the AR.
In this case with a steady supply it would be possible to invest in either a rotating drum or an atomizer.

Silver for inquarting will be a short term investment since you soon will be another product you can sell, each dore will yield 5-6 kg Silver.

You will need about 126kgs if Silver per dore so the first investment will be significant either way you go.

Processing Silver will also be a must either way, since you will extract 5,5-6kgs per dore.

In AR this will be in the firm of AgCl.
With inquarting it can be cemented or the Nitric can be reclaimed and produce AgCl.

This discussion is for you and your team, we can only point to the different methods.
How are your facilities?

 

[kurtak]

We would like to express our gratitude for the valuable comments provided in the forum; they have been incredibly helpful.

You are welcome - that is what we are here for

As gold traders who ventured into the refinery business a year ago, we currently have a daily capacity of refining 30kg using Aqua Regia (AR) as our primary method.

Ok - that is good to know - so though you are not entirely new to refining but relatively new in that you are (more or less) a "start up" of a "fair size" refinery - awesome !!!

Throughout this period, we have successfully carried out the refinery process with less than 7% silver content.

Which you set up to process a particular incoming product (from a particular client I "assume")

However, we recently received a new order to refine a mining dore bar weighing approximately 30-40kg per week, with a silver content of 15%.

So now you have picked up a new client with a new product that is problematic in your current set up

Because this new incoming product is problematic in your current refining circuit (set up) we need to figure out the best path forward to solve the problem

This could range from making a few simpler tweaks/changes in your current refining circuit --- to needing to implementing a new circuit &/or additions to the (current) circuit to handle the new product

Our primary intention in asking this question here is to seek advice from experts regarding alternatives to Aqua Regia. We are searching for methods that can provide us with the optimum amount of gold without incurring excessive costs or consuming too much time.

Per the bold print - regardless of what you do/decide you are (of course) going to incur some cost (time/money) to address the problem

In my opinion (others may chime in with other opinions - which is good) you have 3 options

1) set up a circuit for the inquarting process (keeping in mind you actually have your own silver coming from your incoming product)

2) add a tumbler to your current circuit

3) possibly make a few simple tweaks to your current circuit to accommodate atomization of the new product

Sooooo - what would be really nice here would be to see some pictures of your current refining circuit in order for us to get a better idea of what "maybe" the best path forward

By the way, I'm a 'she' not He. Haha

there is not a thing in the world wrong with that - there are some very fine women in this world of refining - it's not just a mans world

Kurt

 

[nickvc]

If you are still running other material then perhaps good assays and mixing products could help reduce the silver content and or depending on your delivery periods adding more gold to the bars to reduce the silver percentage down to allow dissolution , as I stated before there is no simple cheap way to do this especially in an ongoing situation.
If you had a loss of gold to your silver then you will need to convert your silver chloride to metallic silver and refine it in a cell where the gold will report in the slimes , you will probably find gold in the other silver recovered from your other materials so setting a silver cell up may well be very cost effective and fairly simple to run .

 

[goldandsilver123]

Opps - forgot - but I wanted to ask what you meant by that

I ask because I don't see a lot of difference between pouring to shot/corn flake & pour through an atomizer (other then end product)

The only real difference would be the reaction vessel set up you run those two different products through

That is why I was considering making an atomizer before I decided to retire (wanted to get away from inquarting) --- I already had 20 liter reaction vessels with stirrer setup - so setting up with tumbler would have been a big leap/change in my set up

Kurt

Metal granules are easy to account for, they are big, you can also spot them with easy.

Metal powder is different, it sticks to the vessel, after the atomization part of it takes many minutes to decant, if it splashes on the ground it is very difficult to clean.

I would say, people who do refining just for money would buy the tumbler, but that is just my 2 cents