The core parameters that customers care about most
| Parameters |
Industry standards |
Impact on production |
Test methods |
| Gold loading |
≥300 g Au/ton of carbon |
Determine carbon usage and replacement frequency |
Fire assay (ISO 15249) |
| Adsorption rate |
＞95% (within 1 hour) |
Affects the number of leaching tanks and residence time |
Dynamic column adsorption test |
| Desorption rate |
≥99.9% (high temperature and high pressure method) |
Correlate gold recovery efficiency and carbon regeneration cost |
Sodium cyanide/sodium hydroxide elution |
| Abrasion resistance |
≥95% |
Reduce the loss of fine carbon powder (annual loss <5%) |
ASTM D3802 drum method |
| Particle size |
6-16 mesh (1.2-3.3mm) |
Balance adsorption speed and fluid resistance |
ASTM E11 screening |
| Ash content |
≤3% |
Avoid impurities blocking carbon pores |
GB/T 7702.15-2008 |
|
Three golden rules for selecting activated carbon
Material priority:
Coconut shell charcoal: well-developed micropores (pore size 1-2nm), gold loading 350g/ton (high-grade ore recommended)
Apricot shell charcoal: high strength, wear resistance 15% better than coconut shell (suitable for high-wear CIP process)
Aperture adaptation:
Gold cyanide complex diameter 0.5nm → Choose carbon with micropore ratio > 70%
Regeneration economy:
High-quality carbon can be thermally regenerated 5 times (gold retention rate > 90%), and the cost per ton of carbon is reduced by 40%
III. Actual cases – data speaks
Case 1: CIP process upgrade of a gold mine in South Africa
Pain points: gold loading is only 180g/ton, desorption rate is 92%, and tailings gold loss is 0.8g/ton
The solutions we provide to customers:
Replace high microporous coconut shell carbon (gold loading 320g/ton, strength 98%)
Optimize desorption process (130℃/0.5MPa, NaOH+sodium cyanide)
Results:
Gold recovery rate from 86%→94.5%
Year Increased gold production by 1.2 tons and increased revenue by $72 million
Case 2: Cost reduction and efficiency improvement at Australian heap leaching sites
Challenges: Low-grade ore (1.2g/ton), high consumption of activated carbon
Innovative solutions we provide:
Use apricot shell charcoal (strength 99%, unit price 30% lower than coconut shell)
Mobile desorption electrolysis vehicle (on-site regeneration, transportation cost reduced by 60%)
Benefits:
Treatment cost per ton of ore from $18→$12
Charcoal loss rate from 8%→3.5%
IV. Pit avoidance guide – industry lessons learned
False gold loading trap:
Part of the charcoal adsorbs copper/zinc ions (falsely high gold loading), and a selective adsorption report (gold vs base metals) is required
Fine charcoal powder disaster:
Charcoal with strength <90% produces powdered charcoal → clogging the screen + gold loss (annual gold loss of 35kg in a mine)
Incomplete desorption:
Residual gold >200g/ton? Check the purity of the desorbent (NaOH needs to be ≥99%) and temperature control (error ±2℃)
