TSX-listed Ivanhoe Mines executive co-chairperson Robert Friedland and president and CEO Marna Cloete have announced that the debottlenecking programme at the ultrahigh-grade Kipushi zinc mine, in the Democratic Republic of Congo (DRC), was recently completed ahead of schedule and under budget.

Ivanhoe notes that zinc production from the Kipushi concentrator has significantly improved following the completion of the debottlenecking programme, setting multiple new production records.

Engineering work on the debottlenecking programme began in September 2024 with the aim of boosting the concentrator throughput rate by 20% from 800 000 t/y to 960 000 t/y of ore.

Construction works were completed in early August, following a second and final concentrator shutdown to commission the newly installed equipment.

Concurrent with the integrations of the debottlenecking programme, Ivanhoe says the August shutdown also included additional upgrades to the dense media separation (DMS) circuit to improve equipment availability.

As reported on October 7, 2024, the company explains that excessive fine material (fines) in the ore feed was causing blockages in the DMS circuit, leading to frequent unscheduled shutdowns.

Following the completion of the upgrades during the recent shutdown, Ivanhoe says the DMS circuit availability has increased notably from about 70% to 96%, boosting concentrator recoveries to over 90%.

The company says multiple concentrator records have been achieved since the completion of the debottlenecking programme, owing to both improved concentrator throughput rates and DMS availability.

In the seven days following the early August shutdown, a record 5 545 t of zinc in concentrate was produced, equivalent to a yearly production rate of about 290 000 t of zinc.

Sustaining this run rate would make the Kipushi mine the world’s fourth-largest zinc mining operation, says Ivanhoe.

In addition, a record 1 052 t of zinc in concentrate was produced over 24 hours in mid-August, equivalent to a yearly production rate of over 340 000 t of zinc, after accounting for availability.

Ivanhoe notes that further back-up electrical upgrades continue with the installation of an additional 6 MW in backup generator capacity, which is expected to be commissioned and available in the fourth quarter.

The company says it is anticipated that the back-up capacity will be used to support operations during times of grid instability.

Following the completion of the aforementioned initiatives, the company says it is expected that the rate of zinc production during the remainder of the year will significantly increase, therefore Kipushi’s 2025 production guidance remains unchanged at between 180 000 t and 240 000 t of zinc.

Throughout construction of the Kipushi concentrator, which started in September 2022 and was completed in June 2024, as well as the recently completed debottlenecking programme, Ivanhoe says the project team at Kipushi did not record a single lost-time injury.

“This is an outstanding and incredibly rare industry achievement,” the company says, describing this as an “industry leading safety record.”

Moreover, Ivanhoe notes that a three-year offtake agreement was signed with independent energy and commodity group Mercuria of Geneva, Switzerland, in July.

The agreement is for up to one-third of the remaining unallocated offtake of Kipushi’s high-grade zinc concentrate.

Ivanhoe says offtake agreements for the balance of Kipushi’s zinc concentrate production are already in place with CITIC Metal (HK) Limited of Hong Kong and Trafigura Asia Trading of Singapore, as announced on July 2, 2024.

In addition to the recently signed offtake agreement, the company notes that Mercuria has provided a loan facility of $20-million to Kipushi Corporation over the term of the offtake contract.