BRISBANE, Australia, May 12, 2026 (GLOBE NEWSWIRE) -- North American lithium producer Elevra Lithium Limited (“Elevra or Company”) (ASX:ELV; NASDAQ:ELVR) announced today the outcomes of an Updated Scoping Study for expansion of the existing North American Lithium (NAL) mine. Relative to the study from 15 September 20251 this study delivers additional annual concentrate production two years faster than originally planned, similar unit operating costs and unchanged total capital expenditure of US$270 million.
Highlights
- Process plant design feed rate increased to the permitted average annual 4,500 tonnes per day (tpd) in Stage 1 and 6,500 tpd in Stage 2; average Life of Mine (LOM) recovery of 71.2%; spodumene concentrate at grade of 5.4% Li2O.
- The updated Scoping Study improves the incremental post-tax NPV(8%) of the expansion project from C$479M (US$355M)2 in the previous study1 to C$969M (US$718M)2 or a 102% increase. Approximately 51% of the increase in post-tax NPV is attributable to staging/throughput and other assumption changes while 49% is attributable to the increase in Li2O price from the previous study.
- The expansion project provides a total NAL project post-tax NPV(8%) of C$3,112M (US$2,305M)2, with a post-tax IRR of 41.8% and payback of 25 months.
- The expanded production rate is increased to 338 thousand tonnes per annum (ktpa) (nominal SC5.4, post ramp up), up from 315 ktpa in the prior scoping study1.
- Average LOM C1 unit cost of C$847/t (US$628/t)2 and AISC of C$922/t (US$683/t)2 once the expansion is fully operational similar to the prior study1.
- Stage 1 CAPEX of C$96M (US$71M)2; Stage 2 CAPEX of C$81M (US$60M)2; Stage 3 CAPEX of C$188M (US$139M)2. Total CAPEX of C$366M, (US$270M)2.
- Stage 1 incremental production ramp up will commence in mid-CY27 and Stage 3 construction is forecast to be completed by mid-CY29.
- The Company’s existing NAL Ore Reserves solely underpin the NAL Expansion production profile with a revised life of mine of 21 years.
The NAL Expansion Project will be delivered based on a development sequence identified by Elevra and published on January 12th, 2026, in the ASX press release “Accelerated NAL Expansion”. The following debottlenecking steps were identified for the delivery of the three Stages:
- Stage 1: An initial 15-20% increase in annual spodumene concentrate production above current production levels commencing in mid-CY27 with an incremental reduction in unit operating costs. This increase is within the current limits of the milling permit, which is set at 4,500 tpd;
- Stage 2: A subsequent expansion of downstream milling, flotation and filtration capacity to 6,500 tpd with an anticipated corresponding concentrate production rate of 338 ktpa post expansion. The incremental feed material will be processed using a temporary mobile crushing circuit operating in conjunction with the existing crushing circuit. The further expanded production is expected to commence early CY28, with an additional incremental reduction in unit operating costs; and
- Stage 3: The replacement of the temporary mobile crushing circuit and the existing crushing circuit with a new crushing circuit capable of meeting feed requirements for a LOM average production of 338ktpa. This final step will include additional ore sorting capacity and is expected to be completed in early CY29 delivering crushing cost efficiencies which are required to meet the anticipated LOM cost reduction.
Elevra’s Chief Executive Officer and Managing Director, Mr Lucas Dow, said: “The updated Scoping Study demonstrates the significant value uplift achievable through a staged expansion of the North American Lithium mine. Adopting this staged development approach allows Elevra to bring additional production forward on an accelerated timeline compared with the previously contemplated whole-of-project expansion. Additionally, we see the staged development as a disciplined and practical pathway to growth, allowing us to deliver measurable progress through clearly defined milestones rather than relying on a single step-change outcome. By advancing the project in phases, we can progressively increase production capacity, optimise operating performance, reduce costs and incorporate learnings at each stage of development.
“This approach strengthens execution certainty, supports prudent capital deployment and enables the team to achieve tangible operational and financial objectives along the way, while maintaining flexibility to respond to market conditions. Ultimately, the staged model enables Elevra to build scale responsibly, generate cashflow earlier, improve capital efficiency, and deliver a reduction in unit operating costs to enhance returns and project economics.
“As global lithium demand continues to grow, the Updated Scoping Study, combined with the technical and operational knowledge gained on site, reinforces our confidence in NAL’s expansion pathway and highlights a clear opportunity to deliver sustainable long-term value.”
Updated Scoping Study Metrics
Analysis of the financial model on the key economic assumptions indicates that the Project is robust in terms of operational and financial metrics. The Project is most sensitive to changes in commodity prices, exchange rates, head grades and recoveries, with the key Project assumptions and outputs shown in the tables below (please note that any reference to Base Case means NAL on an unexpanded or “as is” basis):
Table 1 – Main Financial Assumptions and Results Summary for the NAL Expansion Project
| Parameters | Unit | Base | Expansion | |||
| Average Price 6% Li2O3 | USD$/t | $2,261 | $2,154 | |||
| Life of mine (from 2025) | yrs | 35 | 21 | |||
| Total Waste | Mt | 335 | 335 | |||
| Total Ore | Mt | 47 | 47 | |||
| Strip Ratio | - | 7.2 | 7.2 | |||
| Average Annual ROM | Mt/y | 1.3 | 2.4 | |||
| Average Feed Grade | % Li2O | 1.11% | 1.11% | |||
| LOM 5.4% Li2O Produced | Mt | 6.72 | 6.85 | |||
| Average Annual 5.4% Li2O production (post expansion – Life of Mine (LOM)) | kt/y | 194 | 338 | |||
Table 2 – Project Economics
| Project Economics | Unit | Base | Expansion | |||
| LOM C1 Cost Concentrate | C$/t conc | 1,076 | 868 | |||
| LOM AISC | C$/t conc | 1,152 | 946 | |||
| LOM C1 Cost of Concentrate (post expansion) | C$/t conc | 1,071 | 847 | |||
| LOM AISC (post expansion) | C$/t conc | 1,146 | 922 | |||
| Total Sustaining Capital (SUSEX) | C$M | 506 | 526 | |||
| Total Initial CAPEX | C$M | - | 366 | |||
| NPV (8%) (post-tax) | C$M | 2,143 | 3,112 | |||
| IRR Expansion (post-tax) | % | - | 42% | |||
| Payback (post-tax) | Months | - | 25 | |||
Notes:
- All costs and sales are presented in constant 2026 CAD, with no inflation or escalation factors considered.
- $M = millions of dollars.
- The financial analysis was performed on existing Ore Reserves as outlined in this report.
- The valuation calculations are unlevered.
- The average metallurgical recovery over the LOM is 71.2% for the expansion and 69.2% for the base case due to improvement in the mill flowsheet specifically attributable to wet high-intensity magnetic separator (WHIMS) improvements.
- Plant availability is calculated at 90%.
- Tonnes of concentrate are presented as dry metric tonnes.
- An exchange rate of 0.74 CAD/USD was fixed over the LOM for the Project.
- The average 6% Li2O concentrate (SC6) price is based on a market analysis from Benchmark Mineral Intelligence for Q1 2026 as described in the market section and varies over the LOM from US$1,260/t to US$2,430/t.
- Average LOM SC6 pricing may vary between the cases due to longer mine life at the long term US$2,430 price for the base case (2036 and beyond).
- A discount rate of 8% was used for the base case and expansion scenarios.
- Net Cash Flow and valuation calculations include investment tax credit on CAPEX.
- The numbers have been rounded. Any discrepancy in the totals is due to rounding effects.
Cautionary Statements
The Updated Scoping Study discussed herein has been undertaken to determine the feasibility of a brownfield expansion of the existing NAL operation. The Updated Scoping Study is a preliminary technical and economic study of the feasibility of an expansion development of the NAL Operation. The Updated Scoping Study is based on low-level technical and economic assessments and is insufficient to provide assurance of an economic development case at this stage.
The Updated Scoping Study evaluation work and appropriate studies have provided Updated Scoping level estimates of cost and rates of return. The production target underpinning financial forecasts included in the Updated Scoping Study are based solely upon current Ore Reserves estimated in the Announcement (See Sayona ASX announcement dated 27 August 2025).
The Updated Scoping Study is based on the material assumptions outlined elsewhere in this announcement. These include assumptions about the availability of funding. There is no certainty that the Project will be able to be funded when needed (nor any certainty as to the form such funding may take, such as disclosed in this announcement). It is also possible that such funding may only be available on terms that dilute or otherwise affect the value of the Company’s shares. While Elevra considers all of the material assumptions to be based on reasonable grounds, there is no certainty that they will prove to be correct or that the range of outcomes indicated by the Updated Scoping Study will be achieved. This announcement contains forward‐looking statements. Elevra has concluded it has a reasonable basis for providing the forward‐looking statements included in this announcement. However, a number of factors could cause actual results, or expectations to differ materially from the results expressed or implied in the forward-looking statements. Given the uncertainties involved, investors should not make any investment decisions based solely on the results of the Updated Scoping Study and are cautioned not to place undue reliance on the Updated Scoping Study or the production targets referred to in this announcement.
Overview
The North American Lithium operation is a hard-rock lithium mining and concentration facility located in La Corne, within the Abitibi-Témiscamingue region of Quebec, Canada. The NAL facility was successfully restarted in March 2023, and the plant is currently permitted for 4,500 tpd of average annual milling rate.
The processing operation consists of three distinct processing areas:
- The primary, secondary and tertiary crushing, and ore sorting circuits to produce an upgraded plant feed for downstream processing.
- The spodumene processing plant including grinding, desliming, magnetic separation, flotation and dewatering circuits to produce a final spodumene concentrate.
- The process water and utilities circuits including tailings thickeners, reagents preparation, reverse osmosis treatment, and tailings management.
The objective of the NAL expansion project is to increase the plant’s milling throughput to an annual level of 6,500 tpd. Elevra determined that permitting is the critical path constraint and identified a project development sequence that provides a shorter timeframe to achieve increased production from NAL. The additional new permitting information, combined with existing permits, provides a pathway to stage the expansion of production volumes at NAL in a disciplined, agile and more time efficient manner.
The expansion pathway is now proposed to take the form of a series of debottlenecking steps which are expected to:
- Increase production capacity above current levels in a staged and incremental manner;
- Improve plant recovery by the introduction of additional LIMS and WHIMS, and additional flotation conditioning capacity;
- Reduce the timeframe to achieve the expanded average Life of Mine (LOM) production volume of 338ktpa of spodumene concentrate; and
- Enable the capital investment to be staged and, in doing so, reduce the initial upfront capital requirements.
The debottlenecking steps are anticipated to be delivered as below:
- An initial 15-20% increase in annual spodumene concentrate production above current production levels commencing in mid-CY27 with an incremental reduction in unit operating costs. This increase is within the current limits of the milling permit, which is set at 4,500 tpd;
- A subsequent expansion of the milling, flotation and filtration capacity to 6,500 tpd with an anticipated corresponding concentrate production rate of 338 ktpa post expansion. The incremental feed material will be processed using a temporary mobile crushing circuit operating in conjunction with the existing crushing circuit. The further expanded production is expected to commence early CY28, with an additional incremental reduction in unit operating costs; and
- The replacement of the temporary mobile crushing circuit and the existing crushing circuit with a new crushing circuit capable of meeting feed requirements for a LOM average production of 338 ktpa post expansion. This final step is expected to be completed in mid-CY29 and is expected to deliver crushing cost efficiencies required to meet the anticipated LOM cost reduction.
Property Status
The NAL Expansion Project properties (the “Properties”) are situated in the La Corne Township in the Abitibi-Témiscamingue region in the Province of Québec, Canada.
Site Access and Existing Infrastructure
The Project is located approximately 38 km southeast of Amos, 15 km west of Barraute and 60 km north of Val-d’Or in the Province of Québec, Canada. The Project is approximately 550 km north of Montréal and is serviced by road, rail, and air.
The town of Val-d’Or, with a population of approximately 32,750 residents (Canadian Census, 2021), is located 60 km south of the Property, along the provincial Highway 111. Since Val-d’Or was founded in the 1920s, it has been a mining service centre. Val-d’Or is one of the largest communities in the Abitibi region and has all major services, including an airport with scheduled service from Montréal. Val-d’Or is a 6-hour drive from Montréal, and there are daily bus services between Montréal and the other cities and towns in the Abitibi region.
The town of Amos, with a population of approximately 12,675 residents (Canadian Census, 2021), is located approximately 38km northwest of the NAL site. Amos is served by highways 109, 111, and 395 and the Amos/Magny airport.
The site is accessible by provincial Highway 111, connecting Val-d’Or and Amos, or alternatively by provincial Highway 397, connecting Val-d’Or and Barraute. An all-weather secondary road, known as Route du Lithium, connecting the site to the Val-d’Or – Amos highway, which was used to traverse the Property and which constrained pit operations, has now been relocated to avoid the mining area. The site is also accessible from Mont-Vidéo, through an all-weather road that connects further east to the Val-d’Or – Barraute highway. Canadian National (CN) railway line is about 49km east of the Property, connecting east through to Montréal and west to the North American rail network.
A high-voltage power line (120 kV) passes approximately 2 km to the west of the Property and a 25 kV electric line, running along the Route du Lithium, services the Mont-Vidéo ski and recreation area.
Geology and Mineralisation
Results of past mineral exploration, resource evaluation and mining demonstrate that NAL is an extensively mineralised lithium system. The primary metal is lithium, and it is mainly associated with spodumene, a lithium bearing pyroxene.
North American Lithium’s pegmatite dykes occupy an area spanning 3,550 m along strike, 1,300 m in width and 800 m in depth. A total of 117 spodumene-bearing pegmatite dykes each with thicknesses greater than 2 m and up to 70 m are open at depth and have been identified in the NAL geological model. Spodumene crystals are widely and variably spread throughout the dykes, displaying faint greenish shades and sometimes locally displaying centimetric to decametric crystal gradations. Pegmatite dykes display internal zoning.
The Project is located in the region of The Archean Preissac-Lacorne syn- to post-tectonic intrusion that was emplaced in the southern Volcanic Zone of the Abitibi Greenstone Belt of the Superior Province of Québec.
Local geological units are summarised in Table 3 and they comprise (from oldest to youngest): basaltic lavas (Malartic and Kinojevis Groups), biotite schist (Kewagama Group), metaperidotite and monzogranite (La Corne pluton).
Table 3 – Geological Units
| Geologic Unit | Description | |
| Basaltic Lavas Malartic and Kinojevis Groups 2.718 Ma | Volcanic rocks are generally fine-grained and medium to dark green on fresh surfaces. The units are massive or locally exhibit structures such as pillows, flow breccia or amygdule. Under the microscope, the volcanic rocks are mainly green hornblende, plagioclase with minor amounts of quartz, epidote, biotite, and chlorite. Accessory minerals include titanite, apatite, magnetite, pyrite and an alteration product of ilmenite, leucoxene. The abundant green hornblende shows incipient alteration to chlorite or partial replacement by holmquistite. | |
| Biotite Schist Kewagama Group | The biotite schists are conformably interbedded with the basaltic lavas. The schists are mainly sedimentary in origin, derived from greywacke, sandstone, and conglomerate. The biotite schist beds are up to 40 cm thick, fine-grained and are grey to black on fresh surfaces. They are foliated with the foliation parallel with either the contact or the foliation in the outcrops of the Preissac-La Corne batholith. Under the microscope, the biotite schist consists mainly of quartz, plagioclase, and biotite. Hornblende and chlorite are major components in a few beds. The common accessory minerals are apatite, epidote, tourmaline, pyrite, and magnetite. | |
| Metaperidotite | The metaperidotite is interbedded with basaltic lavas and, less commonly, with biotite schists. Metaperidotite is fine-grained and black or dark green in colour. The weathered surface is typically brown and exhibits a variety of textures, including polygonal fracture systems, pseudo-pillow structures and a platy structure, which is likely komatiite. The metaperidotite consists mainly of felted aggregates of chlorite flakes, acicular to prismatic actinolite, fibrous serpentine and talc flakes with accessory magnetite, carbonate, and pyrite. The platy structure consists of planar concentrations of chlorite and serpentine, alternating with similarly shaped concentrations of actinolite and magnetite. Primary olivine and/or pyroxene relicts are pseudomorphed by aggregates of chlorite, serpentine, talc, magnetite, and carbonate. | |
| Granodiorite La Corne Pluton 2,621-2,655 Ma | The La Corne pluton has been described by Mulja et al. (1995a). It is dominated by biotite monzogranite, which gives way inward to two-mica and muscovite monzogranite. The geology of the La Corne pluton is similar to that of the rest of the Preissac-La Corne batholith. | |
| Gabbro/Diabase Dykes Proterozoic age | There are post-batholithic gabbro/diabase dykes that outcrop in the batholith and nearby as tabular bodies up to 60 m wide and several kilometres long, striking either N25º E or N40º E and dipping vertically. The gabbro is fine- to medium-grained and tends to be ophitic. | |
Mineral Resources and Ore Reserves
The project database contains data from 1,575 diamond drillholes surfaces and underground collared, spanning a total of 27,183 records of Li2O assays with a mean sample length of approximately 0.884 m. Li2O grade varies from 0.000% to 5.318%. Global average Li2O grade for raw samples (excluding 0.00% assays) is 0.783%. From this database, a subset of 562 surface collared drillholes totalling 153,047 m was used for the Mineral Resource estimate.
The current Mineral Resource Estimate and Ore Reserve Estimate are presented in Table 4 and Table 5 below. The Mineral Resource and Ore Reserve estimates were prepared by Competent Persons in accordance with the 2012 JORC Code.
Table 4 – North American Lithium – Mineral Resource Estimates (0.60% Li2O cut-off grade for the RPEEE pit and 0.70% Li2O cut-off grade for underground domain)
| Resource Classification | Method | Tonnes (Mt) | Li2O Grade (%) | Cut-Off Grade (%) | ||||
| Indicated | Open Pit | 76.2 | 1.17 | 0.60 | ||||
| Inferred | Open Pit | 8.6 | 1.13 | 0.60 | ||||
| Indicated | Underground | - | - | - | ||||
| Inferred | Underground | 10.3 | 1.01 | 0.70 | ||||
| Total | 95.0 | 1.15 | ||||||
Table 5 – North American Lithium – Ore Reserves Estimate, as at of June 30, 2025
| Resource Classification | Tonnes (Mt) | Li2O Grade (%) | Cut-Off Grade (%) | Fe Grade (%) | ||||
| Proved Ore Reserves | 0.3 | 1.01 | 0.60 | 1.55 | ||||
| Probable Ore Reserves | 48.2 | 1.11 | 0.60 | 0.82 | ||||
| Total | 48.6 | 1.11 | 0.60 | 0.83 | ||||
The information on Mineral Resources and Ore Reserves is extracted from the announcement entitled “NAL Resources and Reserves Increases” published on the ASX on August 27th, 2025, and is available to view on the Elevra’s website on the ASX. The company confirms that it is not aware of any new information or data that materially affects the information included in the original market announcement and, in the case of estimates of Mineral Resources or Ore Reserves, that all material assumptions and technical parameters underpinning the estimates in the relevant market announcement continue to apply and have not materially changed. The company confirms that the form and context in which the Competent Person’s findings are presented have not been materially modified from the original market announcement.
Mine Design
The NAL final pit design was based on a pit optimisation assessment which determined the economic limits of the deposit. The in-pit haul road has been designed on the hanging wall side of the deposit to maximise ore recovery within the pit shell, provide more direct access to the waste storage facilities and ROM and to provide access for the final mining pushback. The final pit reaches a maximum depth of approximately 380m below topography.
The life-of-mine schedule was completed based on a plant throughput authorised at 4,500 tonnes per day. The initial daily processing rate is 3,780 tonnes per day, which is maintained up to July 1st, 2027. The daily processing rate increases to 4,500 tonnes per day annual average from 1st of July 2027 and increases again to 6,500 tonnes per day annual average from 1st of April 2028. Ore mining out of the pit is limited to 4,700 tonnes per day annual average until 1st of April 2028, before increasing to maximum of 7,000 tonnes per day annual average.
The final pit design was subdivided into a total of seven mining phases, with the physicals and ore grades contained within each phase shown in Table 6. Special attention was given to the historical underground openings when setting the physical limits for every phase, with consideration taken to ensure that the phase walls did not intersect the old workings. The current life-of-mine plan will be clear of all historical underground workings by the end of 2030.
Table 6 – NAL Physicals by Phase
| Item | Units | Total | Phase 2 | Phase 3 | Phase 4 | Phase 5 | Phase 6 | Phase 7 | Phase 8 | ||||||||||
| Total In-Pit | Mt | 388.2 | 0.2 | 33.2 | 55.0 | 55.9 | 47.3 | 182.0 | 14.7 | ||||||||||
| Waste Rock | Mt | 340.8 | 0.2 | 27.8 | 47.6 | 49.8 | 40.3 | 162.2 | 13.0 | ||||||||||
| ROM Ore | Mt | 47.5 | 0.01 | 5.4 | 7.3 | 6.1 | 7.0 | 19.9 | 1.8 | ||||||||||
| Lithium Grade | % Li2O | 1.11% | 1.14% | 1.13% | 1.09% | 1.05% | 1.22% | 1.10% | 1.04% | ||||||||||
| Iron Grade | % Fe | 0.82% | 0.59% | 0.89% | 0.91% | 0.85% | 0.75% | 0.79% | 0.71% | ||||||||||
| Strip Ratio | twaste: tore | 7.2 | 11.2 | 5.2 | 6.5 | 8.2 | 5.8 | 8.2 | 7.3 | ||||||||||
The following criteria were applied during the phase design construction:
- Minimum mining width of 60m considered between phases on the surface and 40m at the phase base;
- Ease of access to different mining areas;
- Mining and processing production rate; and
- Physical constraints posed by historical underground workings.
Two life-of-mine schedules were developed for the updated scoping study using Micromine’s Spry software package. The two schedules were:
- A base case schedule utilising a processing rate of approximately 3,780 tonnes per day; and
- An expanded case schedule, with three stages of capital investment gradually increasing the processing production rate up to 6,500 tonnes per day.
Both schedules utilised the same reserves set and dump designs, however due to differing production rates, the schedules finished at different times. The base case schedule ran until 2061, whilst the expanded case schedule was finished in 2047.
For both cases, the LOM schedule utilised similar class equipment that is currently operating at site, with a large 200t excavator added to the fleet to assist with maintaining the required stripping quantities.
The key highlights of the LOM plan are summarised as follows:
- Mine life of 35 years for the base case and 21 years for the expanded case.
- Total of 47.5Mt of ore mined.
- Total of 340.8mt of waste mined, leading to an overall strip ratio of 7.2:1, which fluctuates over the years.
- Crusher feed averages 1.36mt and 2.37mt per annum for the base case and expanded case respectively when operating at full capacity.
- In the base case, crusher feed grade fluctuates from 0.91% Li2O to 1.13% Li2O on a yearly basis over the LOM, reaching its maximum value in Year 2058.
- In the expanded case, crusher feed grade fluctuates from 0.92% Li2O to 1.22% Li2O on a yearly basis over the LOM, reaching its maximum value in Year 2045.
NAL Expansion Concentrator Feed and Production Profile
The Updated Study production schedule is based solely upon current NAL Ore Reserves as of June 30, 2025.
The NAL Expansion concentrator ore feed will be blended at the ROM to control Li2O grade and Fe contamination. The average head grade is 1.11% Li2O over the LOM. Figure 5 presents yearly head feed tonnage and grade over the LOM
The NAL Expansion increases the total process plant throughput to approximately 2.4 Mtpa with a process plant availability of 90%. Based on the LOM Plan, the circuit will on average produce a nominal 338 ktpa of spodumene flotation concentrate, with a 71.2% Li2O recovery at a target product grade of 5.4% Li2O once the expansion circuit is fully operational.
Metallurgy
The NAL deposit has undergone extensive metallurgical test work. Metallurgical recovery assumptions are based on historical metallurgical tests and test work completed during 2018 – 2023. Test work programs began in 2008 to establish the metallurgical character of the orebody, to allow the development of a process flowsheet, to test that flowsheet, to evaluate the impact of head grade on performance, and then to produce the engineering data for plant design. This test work occurred under the supervision of independent QPs and Sayona representatives.
The test work evaluated a number of processing techniques including flotation, DMS, LIMS and ore sorting. The progression of this test work took the form of batch scale tests looking at flotation, DMS and grindability leading to locked cycle tests and then pilot scale continuous tests. WHIMS and DMS were not included in the original flowsheet based on the outcomes of the test work. The test work outcomes formed the design basis of the NAL concentrator that commenced operation in March 2013 but ceased operation in September 2014. This was principally due to higher than anticipated mining dilution of the ore with host rock, and lower than target spodumene recovery and concentrate grade.
Subsequent test work programs were undertaken to characterise and mitigate the effect of the dilution including hardness testing and WHIMS test work (on both plant samples and pegmatite samples of varying levels of dilution of the two major dilution host rocks). The impact of the WHIMS on flotation was also examined, and the final spodumene flotation concentrate was 6% Li2O at an estimated test work recovery of 80 to 83%.
Modifications were made to the plant based upon this test work with the addition of WHIMS units prior to flotation and additional ore sorting capacity on the feed. The plant was restarted in 2017 following these changes and consistently achieved concentrate grades of 5.4 to 6.0% Li2O at recoveries from 55 to 70%. The plant subsequently shutdown due to market conditions prior to name plate capacity being achieved.
Further modifications were made to the plant prior to the restart in 2023, but these were focused on operational issues identified from the previous operation rather than underlying metallurgical issues relating to the ore. (i.e. capacity related).
Historical metallurgical test work from the above-described previous phases, along with current operational performance has been used as the basis for the NAL expansion scoping study.
Based on the previous laboratory test work and current operational performance, an average global recovery of 71.2% at a spodumene concentrate grade of 5.4% Li2O has been applied across the NAL Mine Plan for the purposes of the updated scoping study.
The impact of ore sorters was analysed through statistical methods for impact on recovery from operating data. A recovery increase of 2% above the base case is included in the above 71.2% with additional ore sorting performance testing underway.
Mineral Processing and Flowsheet
NAL's current operations are authorised at 4,500 tpd average annual milling throughput for the processing plant for production of spodumene concentrate. The NAL facility consists of the following distinct areas:
- The primary, secondary and tertiary crushing, and ore sorting circuits to produce an upgraded plant feed for downstream processing.
- The spodumene processing plant including grinding, desliming, magnetic separation, flotation and dewatering circuits to produce a final spodumene concentrate.
- Process water and utilities circuits including tailings thickeners, reagents preparation, reverse osmosis treatment, and tailings management.
In addition to the areas described above, the processing plant includes an area historically designated for the conversion of the spodumene concentrate into lithium carbonate. The existing carbonate facility is not functional and there are no plans to produce lithium carbonate at the NAL facility.
The Updated Scoping Study expansion design follows the staged approach identified by Elevra to reach the following authorised mill throughputs:
- Stage 1: Increase to the limits of the current milling permit at 4,500 t/d average annual rate.
- Stage 2: Expansion to a new milling throughput limit of 6,500 t/d average annual rate.
The expansion targets will be achieved through the following modifications to the existing facility:
- Stage 1: Plant optimisation
- Addition of lump breakers in the crusher circuit to prevent ice lumping of the ore
- Addition of stacksizers to the existing ball mill unit
- Optimisation of the desliming and magnetic separation circuit
- Addition of flotation conditioning tanks
- Refurbishment of lithium carbonate filters for new dewatering unit
- Addition of a new flotation thickener circuit
- Addition of pumping capacity to TSF
- Stage 2: Plant expansion
- Contracting of a temporary crusher to balance plant feed with existing crusher
- Addition of a second ball mill line including stack sizers and trash trommel
- Addition of a third magnetic separation line
- Addition of a new rougher unit and conversion of the existing rougher to scavenger duty
- Addition of a second process thickener to increase capacity
- Stage 3: New crusher construction
- Construction of new crusher and new fine covered ore stockpile complete with reclaim
- Conversion of the existing crusher circuit to an ore sorting facility
Table 7 provides a high-level overview of the main design criteria.
Table 7 – General Process Design Criteria
| Criterion | Unit | Base Case | Stage 1 | Stage 2 | Stage 3 | |||||
| Crushing Plant Availability | % | 65 | 65 | 65 | 65 | |||||
| Processing Plant Availability | % | 90 | 90 | 90 | 90 | |||||
| Total ROM Crusher Feed | t/d | 5,815 | 6,923 | 10,000 | 10,000 | |||||
| Total Processing Plant Feed | t/d | 3,780 | 4,500 |
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