The Joyce Lake DSO Project is a simple dry crushing and screening operation designed to produce lump and fines iron ore products from high-grade direct shipping ore.
Report context
The Joyce Lake DSO Project Feasibility Study, dated December 2022, presents a dry crushing and screening processing route for the production of lump and fines iron ore products. The project is designed to process run-of-mine (ROM) ore at a nominal 6% moisture content, with processing operations limited to approximately 214 days per year, typically from April through November. The feasibility study was prepared for Century Global Commodities Corporation and Joyce Direct Iron Inc. under National Instrument 43-101 guidelines.
Processing route
Process overview
The Joyce Lake DSO flowsheet consists of a two-stage dry crushing and screening process designed to produce lump and fines products. The processing battery limits start at the ROM ore stockpile and end with product loaded into product haul trucks.
ROM ore is delivered from the open pit mine to the ROM ore stockpile area using CAT 777 (or equivalent) trucks. Sufficient stockpiling space is provided to allow segregation of ore for blending feed materials ahead of the crushing plant to minimize product grade variability. A dedicated front-end loader of 16 tonnes capacity is used for maintaining the ROM stockpile and for feeding the plant.
The front-end loader transfers material from the ROM stockpile to a feed hopper fitted with a static grizzly screen to scalp off any oversized material (+600 mm). No rock breaker is provided; the +600 mm material is rejected to a stockpile to be processed later by a contractor once sufficient material has accumulated.
Crushing and screening circuit
The material passing the static grizzly is directed onto a vibrating grizzly feeder that separates material at 130 mm prior to the primary crushing stage. The oversize material (+130 mm) is fed to a jaw crusher where it is crushed to a top size of 225 mm. The undersize material from the static grizzly joins the jaw crusher product, and the combined materials are conveyed to a triple-deck horizontal screen.
The triple-deck screen separates the material into three products:
- Oversize +31.5 mm material conveyed from the top screen deck to a cone crusher for further size reduction to a targeted top size of 32 mm
- Lump product (-31.5/+6.3 mm)
- Fines product (-6.3 mm)
The material discharged from the cone crusher is returned to the triple-deck screen, operating in closed loop to ensure that no material coarser than 31.5 mm is sent with the final lump product. A third deck was added to the screen to relieve the load on the 6 mm screen, alleviating excessive bed depth issues and inefficient screening that might be encountered in separating the fines and lump products.
The proposed ROM particle size distribution used for design assumes a relatively coarse feed to ensure sufficient processing capacity during extended periods of harder ore processing. The design accounts for the possibility that, during periods of mining in areas where ore is highly fractured, a significant amount of ore will likely bypass the jaw crusher.
Product handling and stockpiling
Fines material is placed into stockpiles. The fines product stockpile has a design capacity to hold 16 hours of material to allow for scheduled plant maintenance shutdowns. Lump material is fed to a rotary dryer prior to being discharged onto a radial stacker, placing the dried lump into stockpiles. The lump stockpiles reach a maximum capacity of nearly 900,000 tonnes, representing the full year production of lump material. The stockpile is tarped progressively throughout the year to avoid re-wetting, and the pad is designed with drainage to avoid pooling of rainwater.
Process plant lump and fines products are loaded into haul trucks for transportation to the Astray rail load out area. Fines are loaded and hauled during the summer months and lump during the winter months. A 95-tonne capacity Kenworth side-dump chassis with an additional side dump trailer attached was selected for product transport.
A dedicated front-end loader with a nominal capacity of 16 tonnes is required to load the haul trucks and manage the product stockpiles, including emergency stockpiles. Cycle time analysis indicates this equipment would have a utilization rate of about 60% during the operating season. A Twin Shaft Sizer unit will be installed on-site as a feed breaker to reduce frozen chunks to manageable sizes as mitigation against material freezing in the lump stockpile.
Low-grade material management
Material grading between 52% and 55% Fe will be stockpiled in low-grade stockpiles for processing through the dry plant at the end of mine life. Waste material grading between 50% and 52% Fe will also be segregated from other waste and stockpiled for potential future processing.
A 2014 trade-off study compared the selected dry processing flowsheet against a scenario incorporating wet processing to upgrade material having Fe grade between 50% and 55% Fe. The wet processing scenario assumed an overall iron recovery of 75%, with wet scrubbing and screening sufficient to produce a lump product (-31.5/+6.3 mm) grading 57% Fe from low-grade material. The trade-off study concluded that the wet plant scenario would not improve the financial performance of the project due to higher operating costs, lower annual revenues from increased penalties, and substantially higher capital costs. The Joyce Lake deposit does not contain enough material in the 50-55% Fe range to justify the addition of a wet processing plant.
The qualified person recommends that ore sorting test work be developed and executed during operations targeting low and below cut-off grade material. The low-grade lump product created in the crushing circuit is within an ideal range for typical ore sorting applications. Material produced during the first years of operation could be passed through an on-site test unit to assess the potential for upgrading low-grade material.
Drying system
Lump material is dried to a target 2% moisture using a rotary dryer before stockpiling. The rotary dryer is run directly on diesel fuel, with an estimated yearly diesel consumption of 1.1 million litres. Product moisture expectations are 2% for lump and 7% for fines, both respecting typical shipping liquefaction limits for iron ore. The rotary dryer serving for lump drying could be used as a mitigation measure in the event of higher than acceptable moisture content in the fine material.
Operating season
The processing facility is designed to operate for a maximum of 214 days per year, with operations not intended during the colder winter months, typically between mid-November to mid-March. Inclement weather could shorten the production season to as little as 200 days. The crushing and screening circuit is designed to produce 2.5 Mtpa within a shortened (200 days) season. Annual product production and sales are based on the annual mine plan of 2.5 Mtpa of ore tonnes, while the plant design is based on an annual maximum production of 3.0 Mtpa of product.
Process design criteria
The plant is configured as a two-line mobile plant with each line designed to process 50% of the total process throughput, equivalent to 350 tonnes per hour. The two half-lines mobile plant design was retained for reasons of cost, flexibility, and reliability, including the possibility of using the two lines at separate locations during project construction if necessary.
Key process design criteria include:
| Criteria | Unit | Value |
|---|---|---|
| Annual plant feed (dry basis) – design | tpa | 3,000,000 |
| Annual plant feed (dry basis) – nominal | tpa | 2,500,000 |
| Operating time (days per year) | d | 200-240 |
| Operating time (nominal) | d | 214 |
| Operating time (hours per day) | h | 24 |
| Equipment utilization | % | 75 |
| Lump size | mm | 6.3 – 31.5 |
| Fines size | mm | 0 – 6.3 |
| Lump undersize tolerance (<8 mm) | % | 10 |
| Fines undersize tolerance (<100 µm) | % | 15 |
Project website: http://centuryglobal.ca/projects/joyce-lake-attikamagen/
Major mechanical equipment
| Equipment | Description | No. of Units | Size | Installed Power (kW) |
|---|---|---|---|---|
| Grizzly | Bar spacing – 600 mm x 600 mm | 2 | TBD | N/A |
| Feed hopper | Capacity = 35 t | 2 | TBD | N/A |
| Vibrating grizzly feeder | Bar spacing at discharge = 130 mm | 2 | 1.3 m x 6.0 m | 30 |
| Jaw crusher | Capacity = 240-780 t/h; Closed side setting = 50-175 mm | 2 | 0.8 m x 1.4 m | 132 |
| Secondary screen | Triple-deck horizontal screen | 2 | 2.1 m x 6.1 m | 37 |
| Cone crusher | Capacity = 150-470 t/h; Closed side setting: 13-51 mm | 2 | 3.2 m x 2.4 m x 2.7 m | 200 |
Particle size distribution
The particle size distributions do not account for any product degradation, neither on-site nor in transport. Due to the hard nature of the material, product degradation is assumed to be minimal. No penalties have been accounted for in the analysis for the production of very fine material (-100 µm) or the degradation of lump into fine material.
Simulated lump and fines particle size distributions:
| Screen size (µm) | Lump Cumulative Passing (%) | Fines Cumulative Passing (%) |
|---|---|---|
| 31,500 | 100 | 100 |
| 25,400 | 93.5 | 100 |
| 19,050 | 75.8 | 100 |
| 12,700 | 40.3 | 100 |
| 6,700 | 4.0 | 98.1 |
| 4,750 | 0.2 | 82.1 |
| 2,360 | 0 | 47.9 |
| 1,180 | 0 | 29.8 |
| 600 | 0 | 21.6 |
| 300 | 0 | 14.6 |
| 150 | 0 | 10.4 |
| 106 | 0 | 8.3 |
| 75 | 0 | 7.1 |
Key reported parameters
| Parameter | Unit | Value | Basis |
|---|---|---|---|
| Annual plant feed (dry basis) – design | tpa | 3,000,000 | Design |
| Annual plant feed (dry basis) – nominal | tpa | 2,500,000 | Nominal |
| Lump size | mm | -31.5/+6.3 | Design |
| Fines size | mm | -6.3 | Design |
| ROM nominal moisture | % | 6 | Design |
| Dried lump target moisture | % | 2 | Design |
| Fines product moisture | % | 7 | Expected |
| Jaw crusher work index | kWh/t | 10.6 | Testwork |
| Abrasion work index | g | 0.56 | Testwork |
| Lump stockpile capacity | t | 900,000 | Design |
| Fines stockpile capacity (16h) | t | 4,000 | Design |
| Emergency stockpile capacity | t | 24,000 | Design |
| Total process plant power demand | kW | 1,081 | Design |
| Rotary dryer diesel consumption | ML/year | 1.1 | Design |
| Product transportation | – | 95 t Kenworth side-dump with trailer | Design |
| Product loading equipment | – | 16 t front-end loader | Equipment utilization ~60% |
Technical qualifications
Specific limitations identified in the report include:
- The particle size distributions presented do not account for any product degradation, neither on-site nor in transport. Product degradation is assumed to be minimal due to the hard nature of the material, and no penalties have been accounted for in the analysis for the production of very fine material (-100 µm) or the degradation of lump into fine material.
- The crushing and screening circuit design criteria were first developed by BBA using simulation software with input test work results. As part of the request for budgetary proposals, vendors performed their own analysis and proposed equipment and arrangements to meet targeted throughput with ore characteristics provided from the client's test work.
- Further targeted test work is recommended prior to final design to confirm the selected crushing circuit design, as well as the iron grade content of lump and fines products, over a range of ROM iron content process feed grades.
- The annual production figures reference a Wisco specification dated September 2014 for certain elemental values (S, P, As) that were not developed for the mine plan. Values for these elements are averages from test work on bulk samples.
- The design accounts for the possibility that inclement weather could shorten the production season to as little as 200 days; the crushing and screening circuit has been designed to produce 2.5 Mtpa within a shortened season.
- The 2014 trade-off study assumed an overall iron recovery of 75% in wet processing, and some assumptions in that study were not supported by sufficient test work and would require significantly more test work for confirmation.
- There is a risk that portions of the lump stockpile could freeze into chunks not suitable for transportation; a Twin Shaft Sizer unit is included as mitigation. Stockpiles will be tarped progressively throughout the year to avoid re-wetting, and the pad is designed with drainage to avoid pooling of rainwater.
Source: Joyce Lake DSO Project , 2022 Technical Report, Feasibility Study for the Joyce Lake DSO Iron Ore Project, December 2022, Chapter 17: Recovery Methods, Sections 17.1, 17.2, 17.3, 17.4, 17.5, 17.6, 17.7, and 17.8.
Consolidated report summaries
The following former standalone pages about this operation were consolidated here in October 2026. They are retained for source traceability; dates and figures reflect each report’s own effective date and may be superseded by the current information above.
Joyce Lake DSO Project Plans a Two-Line Mobile Crushing Plant Near Schefferville
The 2015 feasibility study for Century's Joyce Lake direct shipping iron ore project chose dry crushing and screening to turn all mined ore into lump and fines, with no process rejects.
The Joyce Lake Direct Shipping Iron Ore (DSO) project lies in Labrador, about 20 km northeast of Schefferville, Québec, and can only be reached by air. It forms part of the Attikamagen Property, held 100% by Labec Century Iron Ore Inc. (LCIO), a joint venture 60% owned by Century Iron Mines Corporation through Century Iron Ore Holdings and 40% by WISCO Canada Attikamagen Resources Development & Investment Limited. The feasibility study by BBA, with an effective date of March 2, 2015, covers an iron ore development project with 17.72 Mt of mineral reserves to be mined by open pit over about seven years. Nominal output was 2.5 Mtpa of lump and sinter fines, trucked to a rail loop and railed to the IOC port at Sept-Îles. The report does not set a construction start date.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Mineral reserves | 17.72 | Mt | Processed over about 7 years |
| Nominal plant feed | 2,500,000 | tpa | Dry basis, per mine plan |
| Design plant feed | 3,000,000 | tpa | Dry basis, maximum capacity |
| Line capacity | 350 | tph | Each of two mobile lines |
| Average feed grade | About 62 | % Fe | High grade ore |
| High grade cut-off | 55 | % Fe | Low grade 52% to 55% Fe stockpiled |
| ROM moisture | 6 | % | Nominal |
| Operating days | 240 | days per year | No winter operation |
| Equipment utilization | 75 | % | Design criteria |
| Lump product size | 6.3 to 31.5 | mm | Higher value product |
| Fines product size | Less than 6.3 | mm | Penalty if over 15% below 100 µm |
| Crusher work index | 10.6 | kWh/t | Jaw and cone crushers |
| Plant power demand | 865 | kW | Estimated draw |
| Haul distance to rail loop | 43 | km | Bi-train side dump trucks |
| Initial capital cost | 259.6 | $ million | Including indirect costs and contingency |
Overview
Joyce Lake is a direct shipping ore project, so the plant only sizes the ore. Run-of-mine ore averaging about 62% Fe goes through two stages of dry crushing and screening to make a lump product and a fines product. All mined ore becomes saleable product. BBA notes that 62% Fe is the benchmark grade at which no iron premium or penalty applies. Lump should upgrade slightly during processing as finer silica reports to the fines.
Early in the study, BBA ran a trade-off between dry processing alone and adding a wet plant to upgrade 50% to 55% Fe material. The wet case assumed scrubbing and screening for lump at 57% Fe, plus wet high intensity magnetic separation and desliming for a fines concentrate, at 75% overall iron recovery. It lengthened the mine life and raised saleable tonnage. Higher operating costs, higher capital and lower average prices from grade penalties meant it did not improve the project's finances. The study found that the deposit holds too little 50% to 55% Fe material to justify a wet plant.
The study therefore kept the simple dry flowsheet. Material between 52% and 55% Fe goes to low grade stockpiles for processing at the end of mine life. Waste between 50% and 52% Fe can be stockpiled separately in case markets change, though the study treats it as waste.
Key Process Stages
Feed and scalping
Mine haul trucks deliver ore to a run-of-mine stockpile pad with room to segregate ore by grade for blending. A 16 t front-end loader manages the pad and feeds the plant, at about 50% utilization during the season. It tips ore into a feed hopper fitted with a static grizzly at 600 mm. There is no rock breaker. Oversize goes to a stockpile, and a contractor breaks it in batches once enough has built up.
Primary crushing
Material through the static grizzly reaches a vibrating grizzly feeder that splits at 130 mm. The +130 mm fraction goes to a jaw crusher with a top size of 225 mm. The jaw product and the grizzly undersize combine on a common collecting conveyor. Where the ore is highly fractured, much of it is expected to bypass the jaw crusher.
Screening and secondary crushing
A triple deck horizontal screen splits the combined stream three ways. The +31.5 mm material goes to a cone crusher, which crushes to a target top size of 32 mm and returns its product to the screen. Because the cone runs in closed circuit with the screen, nothing coarser than 31.5 mm reaches the lump product. The -31.5/+6.3 mm fraction becomes lump and the -6.3 mm fraction becomes fines. A double deck screen would normally do this job. BBA added the third deck to unload the 6 mm deck and avoid deep beds and poor screening between lump and fines.
Product stockpiles and loadout
Each product drops through a chute onto its own conveyor and stacker. The lump stockpile holds about 9,000 t and the fines stockpile about 4,000 t, both roughly 16 hours of output to cover planned maintenance. There is space for 24,000 t emergency stockpiles of each product. A second 16 t loader fills the product haul trucks and runs the stockpiles, at about 60% utilization. Processing ends when product is in the trucks.
Additional Interesting Data and Summary
Vendors were asked to propose their own equipment arrangements. BBA weighed mobile and semi mobile plants and one-line and two-line layouts, and picked two mobile half-capacity lines of 350 tph each. The choice offered lower cost and flexibility, including the option of running the lines at separate locations during construction.
Each line has a 35 t feed hopper, a 1.3 m by 6.0 m vibrating grizzly feeder of 30 kW, a 0.8 m by 1.4 m jaw crusher of 132 kW, a 2.1 m by 6.1 m triple deck screen of 37 kW and a cone crusher of 200 kW. The jaw plants draw 221 kW in total, screening 78 kW, cone crushing 393 kW and conveying 173 kW.
The plant is sized for 100% hard ore, with a relatively coarse design feed size so it keeps its capacity through long hard ore campaigns. The design size distribution has 60% passing 256 mm and 14% passing 32 mm. The plant does not run between mid-November and mid-March.
A separate trade-off found road haulage cheaper than a rail spur from the Schefferville line. Bi-train trucks with two 75 t side dump trailers carry 145 t per trip on the 43 km road to the rail loop. The fleet needs ten trucks, plus one spare. BBA recommended more targeted test work during detailed engineering to confirm the crusher selection and the lump and fines grades across a range of feed grades.
Key Processes
- Static grizzly scalping at 600 mm with contractor breaking of oversize
- Vibrating grizzly feeder split at 130 mm
- Jaw crushing of primary oversize
- Triple deck screening into oversize, lump and fines
- Cone crushing in closed circuit with the screen
- Separate lump and fines stockpiles with emergency storage
- Truck haulage of products to a rail loop
Source: NI 43-101 Technical Report – Feasibility Study, Joyce Lake Direct Shipping Iron Ore (DSO) Project, Attikamagen Property, Labrador, March 2, 2015.
Project website: Joyce Lake DSO Project
