Applications

EMS^® technology can concentrate pregnant leach solution for SX EW copper extraction. Copper concentrations in typical copper streams can be increased by 50–150% and sometimes more.

The resource recovery system extracts a purified water stream from the copper solution. Concentration of the copper is accomplished by the extraction of the purified water stream. An EMS^® system operating on an 8,000 M³/day process stream can produce 4,000 M³/day of purified low-pH water and 4,000 M³/day of 2x concentrated copper solution.

EMS^® Demonstration of Copper Concentrate in an Acid System

• The system increases the tenor of the copper solution reaching the SX circuit without increasing the process volume to enable more corpper to go to the EW from a fixed-size SX asset.
• The ability to concentrate copper values in side streams with non-operable copper levels. Higher concentration factors are possible on dilute streams.
• Generation of a purified water stream. Purified permeate is typically very low in TDS and metals. This permeate can be easily polished by other methods to meet standards for process water or discharge if a mine water imbalance exists. Alternatively, permeate can be blended with the raffinate for leach cycle re-use.
• The existing SX EW system can process 50–100% more copper.
• Membrane modules can be incrementally added.
• Less liquor volume to pump by locating the membrane concentration system at the heap leach site.
• In most instances, concentrated liquor can be delivered to the SX EW site via the membrane operating pressure.
• Optimum copper concentrations in the copper leach liquor. The copper concentration delivered to the SX EW process can be set by varying the membrane system recovery rate.

Most copper electrowinning plants operate a bleed of electrolyte to control the concentration of ions such as iron, manganese, chloride or nitrate. The application of EMS^® technology uses the different ionic behaviors of these contaminants across an engineered membrane to produce a reduced-volume bleed stream significantly lower in copper, cobalt and acid than the original stream.

• Reduced cobalt losses to bleed
• Reduced copper reprocessing
• Reduced bleed volume and make-up
• Reduced acid losses to bleed

The EMS^® can remove entrained organic from electrolyte and raffinate to very low, tenth-of-a-part-per-million, levels. The electrolyte treatment improves the cathode quality by eliminating organic blistering, and improves the safety of the tankhouse by preventing the formation of organic vapors. The recovery of organic from raffinate has the immediate payback of reduced organic loss. The EMS^® removal of organic from the raffinate also precludes the need for the organic removal coalescer and the skimming pond.