Hydrometallurgy: Leaching in Heap, Vat, CIL, CIP, Merrill–Crowe, SX Solvent Extraction

Hydrometallurgy: Leaching in Heap, Vat, CIL, CIP, Merrill–Crowe, SX Solvent Extraction

  • To participate in the 911Metallurgist Forums, be sure to JOIN & LOGIN
  • Use Add New Topic to ask a New Question/Discussion about Hydrometallurgy.
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

trouble with carbon (2 replies and 1 comment)

j
jovanifirebird
6 years ago
jovanifirebird 6 years ago

hi guys.  i work in a gold processing plant. we are facing with some issues. carbon started to go down while density was high( 46%). at the top, carbon is very less, while at the bottom, its high. in my point of view carbon can only go down when density of the slurry is less, but in this case density is high. how about flocculant? do u think it affect it that much for the carbon

thanks

T
Todd H
6 years ago
Todd H 6 years ago
Like
1 like by Rahil Khan

A bit more detail will help find the cause:

What type of leach circuit are we talking about? CIP, CIL, VAT...

When you say does down - do you mean it is sinking in the tank?

Carbon has an SG of 0.5 roughly, so high slurry density will cause it to float more but the tank agitator should keep the carbon mixed, if not perhaps it is an agitation issue.

Todd Harvey - Global Resource Engineering http://www.global-resource-eng.com

Rahil Khan
6 years ago
Rahil Khan 6 years ago
Like

Hello ,
I would like to share with you through my experience because even in my Plant i use to observe the same problem,

  1. Make sure you control O/F slurry density around 48% - 50 % by solid where CIL Density make sure it sure ranges 46%-48% .
  2. Density homogenization in all CIL tanks it depend on the feed density, once it changes within 2 - 3 hrs it affect the whole entirely down stream, so after controlling that Feed density make sure Grinding/ Mill Operator run for 24 hrs to build that density in all CIL tanks as the retentions time.
  3. After density homogenize in all tanks Carbon will start to come up and the profile will increase too.
  4. If you find out carbon are down and you need to continue with elution batch, you can install the carbon recovery pump down the CIL tanks where you can use it to pull the carbon while Density controlling is in progress.
    Also beer in your mind that When carbon are down the tanks it doesn't mean are at the bottom, they are usual at the certain height from the bottom of the tanks where they create the carbon layer.
  5. Also ensure CIL Operator doesn't allow by pass from tank to tank, and also inter tank screen supposed to be cleaned at least 1 a day. Finally O/F supposed to be controlled around that set point , by doing so Carbon will come up and the profile will increase in each tank, hence carbon recovery for Stripping batch will be On progress.
j
jovanifirebird
6 years ago

Hi Rahil. Thanks for the reply. Definitely agree with you. The tanks are homoginized well. Density at the top and down the tanks are same. 46-47%. Yet most of the carbon is still down. Carbon is not at the bottom, you r right. Its at some height. I took sample from that using the back transfer pipes, and my carbon is there. The choise for elution is good enough. But carbon is still down. I observed one thing, slurry seemed to settle rapidly. This is why i thought about flocculant problem. May be my slurry is overflocculated. Because homoginization is good. Oxygen is too good for the tanks. Density is even good enough to work with, what else would it be?


Please join and login to participate and leave a comment.