• To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Mineral Processing or Laboratory Work.
  • 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.

PCB (Printed circuit board) Sampling (2 replies)

Marshal Meru
9 months ago
Marshal Meru 9 months ago

How many do I have to sampling for analysis assaying of metal in crushed PCB(Printed Circuit Board)? I sieved that 6-7 fraction.I'm very eager for successful sampling. Actually I got different results whenever I analyze PCB and Electronic components. That's big problem to estimate those value.

'6-7 fraction' means sizes(divided into 6-7 size range from 2mm to 125 micron meter)

Tony Verdeschi
9 months ago
Tony Verdeschi 9 months ago

Depends what precision you would like. Though this is not my area of expertise (I'm more used to rocks) I suggest make up a lot that would consist of 15 to 30 sub samples - perhaps a 3kg? Crush/cut it all to a small size (perhaps 2 mm) then split the lot using a rotary splitter or riffle splitter into the 15 to 30 sub samples. Pulverise each of the sub sample and assay (I expect you will need to burn of the plastic first?). The average of the sub samples should be a reasonable estimate of the grade of the lot - the individual sample grades will give you the spread of results - you can then think about whether this is sort of precision you are looking for ?+/- perhaps 5-10% or better.

9 months ago
Standartenfurer 9 months ago

Biggest issue you'll face is the potential variability of the boards. So long as it is economically viable granulate the bulk material as small as possible to reduce the potential variability. Sub sampling will be difficult, because you have three main components, ferrous, non-ferrous and non-metallic. The density variable can create a sampling bias and skew your numbers.

You made a comment that you sieved 6-7 fractions? Can you give me some more information? Secondly, how are you looking to process your bulk sample for analysis?

Finally, the comment i made earlier is critical. 'So long as it is economically viable' the value: cost of processing ratio is very important. I'm sure given the equipment you can granulate to -2mm. However the time and cost may be prohibitive. Therefore you now face a challenge. What is the optimum size to granulate and still get a reasonable indicative sample? Often drawing bulk samples in duplicate or triplicate for the start of a project can yield some good data, but the cost of analysis for Cu, Ag, Au&Pd (ignoring the base metals) isn't cheap if you want reliable results.

Please join and login to participate and leave a comment.