GOLD PROCESSING
ENDURON HPGR boosts energy efficiency at Lafigué
New orebodies are increasingly located in remote, difficult to access regions. This presents logistical challenges: these sites often lack established infrastructure, transportation costs are typically high and maintaining reliable supply chains can be challenging. drives. This helped streamline installation.
“ Weir also supported the design and provided advice and guidance on how the workshop should be laid out in order to streamline HPGR maintenance,” it said.“ This is the first time a workshop has been built next to the HPGR in Africa.”
Because of the site’ s remoteness, there were concerns about delivering the HPGR on schedule and, once installed, servicing and maintaining it efficiently to ensure production wasn’ t interrupted.
The rolls on the ENDURON HPGR for Lafigué measure 1.6 m x 1.6 m( diameter x width) and the one roll assembly, including the bearing block assembly, weighs around 50 t. Needless to say, transporting these abnormal loads every time the tyres need to be refurbished is complex, heavily reliant on third parties and subject to unforeseeable disruptions, all of which increases the likelihood of something going wrong.
The tyres are refurbished on site in the workshop, thereby significantly de-risking operations and developing local skills. The workshop has a significant footprint because a lot of space is required to facilitate the tyre exchange.
Endeavour opted for a HPGR-based flowsheet over a SABC circuit
This is true of Endeavour Mining’ s Lafigué open-pit mine, around 330 km north-northwest of Côte d’ Ivoire capital Abidjan. As a result, de-risking the project and ensuring the mine owner could maintain control of its on-site operations was prioritised during the mine planning. Endeavour worked with the EPC firm Lycopodium.
The Lafigué mine, which is expected to produce 200,000 oz / y at full capacity, is mostly fresh rock, which is highly competent and abrasive. Designing mineral processing plants to process very competent ores requires a robust and flexible comminution circuit that, despite feed variability, can deliver a consistent and stable product to the recovery circuit, Weir says.
In saying that, the inter-particle crushing and grinding of high pressure grinding rolls( HPGRs) is highly effective at reducing competent ores, while also increasing the throughput of downstream mills and reducing the circuit’ s overall energy consumption, the OEM says. Moreover, inter-particle grinding creates micro-cracks in the ore, promoting improved mineral recovery at coarser size fractions. This, in turn, means leach reagents are required and leaching periods are shortened, reducing costs and maximising recovery in less time.
“ We worked with Endeavour closely to understand the challenges of the site’ s ore characteristics and support their commitment towards maximising energy efficiencies wherever possible,” the company said.
“ These were key drivers in Endeavour’ s decision to opt for a HPGR-based flowsheet over a SABC circuit. Endeavour wanted to utilise HPGR technology rather than a SAG mill circuit to increase energy efficiency, lower grinding media consumption, reduce the carbon footprint and, ultimately, lower operating costs and ensure a more consistent throughput.”
The customer overcame the perceived HPGR circuit complexity by partnering with Weir and designing an on-site HPGR repair workshop, it added.
Weir delivered its ENDURON ® HPGR so that it could be installed modularly. It was pre-assembled at its factory in Venlo, the Netherlands, and it arrived at the site as one unit excluding the
Fully commissioned ENDURON HPGR at Lafigué mine
During the cold and hot commissioning, Weir trained the Endeavour team. Endeavour now does the first line maintenance, but Weir regularly has its personnel on-site to provide support.
Weir’ s HPGR specialists also fly as required to provide additional support, assistance and on-going training. There is also a weekly call scheduled with the technical team to discuss things like spare parts, roll change support, lead times, tools, etc.
Since its installation at Lafigué, the ENDURON HPGR has delivered strong operational performance and reduced energy consumption, Weir says.
In addition to reliability, the HPGR has driven significant energy savings, consuming 22,800 MWh less energy per year than a SAG mill – equivalent to 18,500 t of CO₂ emission savings per year. Financially, this translates to an annual operating expense reduction of $ 2.6 million and, when extrapolated over the mine’ s 13-year life of mine, a total energy saving of around $ 33.8 million.
The HPGR also produces a finer product and reduces the bond work index in the ball mill, resulting in additional downstream energy savings and improved milling efficiency.
But this is still only a partial picture; it doesn’ t, for instance, take into account the operating expense reduction and avoided embedded emissions as a result of the lower grinding media consumption.
20 International Mining | NOVEMBER / DECEMBER 2025