Jacobina Mine — 2023 Technical Report

Executive Summary

The Jacobina mineral processing plant utilizes conventional gold processing methodologies to treat run-of-mine (ROM) material sourced from underground mines. The comminution circuit consists of three stages of crushing followed by wet grinding. Within the grinding circuit, gravity concentration of gold is performed on a bleed stream of classification cyclone feed. The process flow sheet includes crushing, grinding, gravity concentration, leaching, carbon-in-pulp adsorption, elution, electrowinning, and smelting.

The crushing circuit reduces ore size through a jaw crusher followed by secondary and tertiary cone crushers, achieving a final product size of 80% passing 8 mm. The grinding circuit employs ball mill/cyclone combinations to prepare the feed for the leach circuit, with ore ground to 80% passing 170 µm. A portion of the circulating load is processed through Knelson gravity concentrators, recovering an estimated 50% of the gold in the plant.

The leaching circuit consists of seven tanks with a total capacity of 5,450 m3, using cyanide leaching followed by carbon-in-pulp (CIP) adsorption. Loaded carbon is stripped in an elution circuit and gold is recovered via electrowinning. The resulting sludge and solids are dried and smelted in an induction furnace to produce doré bars with a nominal composition of 96.5% gold, 3% silver, and 0.5% other metals.

Processing Profile

• Crushing: Jaw Crusher (Primary), Cone Crushers (Secondary, Tertiary)
• Milling: Ball Mill
• Gravity: Knelson Concentrators, Falcon Concentrator
• Leaching: Cyanide Leaching (7 tanks)
• Adsorption: Carbon-in-Pulp (CIP)
• Elution: Acid Wash Column, Elution Column
• Smelting: Induction Furnace

Reports

Website: https://panamericansilver.com/operations/gold-segment/jacobina/

Report Date: 2023-06-30

Region: Not specified in text

Project Status: Operating

Commodity: Gold, Silver

Throughput: 920 t/h

Mine Life: N/A

Mine Type: Underground

Ore type: