Increasing Gold Mine Capacity while Ensuring Environmental Compliance

Increasing Gold Mine Capacity while Ensuring Environmental Compliance

The Challenge

A Canadian gold mine needed to increase mine capacity from 800 tpd to 1200 tpd while not increasing its heavy metals concentration to the environment in order to remain compliant with the Ministry of Environment permit limits.



The Solution

Veolia Water Technologies supplied a bundled package of an ACTIFLO® clarifier, together with Hydrex chemicals. The Hydrex program included Hydrex 3253 (ferric sulphate) at 250 mg/L in combination with Hydrex 6105 (anionic polymer) at 10 mg/L. The mine was able to attain the increased production targets within the discharge compliance limits. 


Process Description 

The general WTP's process consists of metal precipitation in reactors followed by Actiflo clarification, in order to meet Provincial Water Quality Objectives. The plant has been designed to operate 24 hours a day. 


The Results

The Actiflo-Hydrex combination produced a treated water with the following characteristics: 

  • Total Suspended Solids < 15 mg/L
  • Total Molybdenum < 0.47 mg/L
  • Total Copper S 0.08 mg/L Total Zinc s 0.02 mg/L
  • Total Iron S 0.18 mg/L
  • Total Antimony 0.24 mg/L 100% survival of daphnia magna and juvenile rainbow trout (i.e.. Low toxicity) 

The Client

A large Canadian gold mine with operations worldwide.