IN-PIT CRUSHING & CONVEYING
quarter of 2025 from the Minerals area, and the other equipment in the first quarter of 2025.
A similar compact crushing plant has already been supplied to ArcelorMittal’ s Serra Azul iron ore mine which was commissioned last year; it also handles compact itabirite ores as the friable material has been mined out. It includes three energy-efficient secondary comminution, with three Metso VTM4500 Vertimill ® mills in combination with two HRCe™ HPGRs, which are all preceded by a Superior™ MKIII 5065 primary crusher. The plant also uses Metso Nordberg ® HP400™ cone crushers plus large banana and horizontal screens. The plant will feed a new pellet production plant with high-quality ore that will integrate into ArcelorMittal’ s global steel production network, with contracted supply to the group’ s steel plants located in Mexico.
However, the largest compact crushing operation ever built in Brazil is underway at Vale’ s S11D mine – this will have a huge 50 Mt / y capacity and is costing Vale some
US $ 755 million to build. In its recent September 2025 Minas Gerais analyst tour, Vale stated that this is still on track to open in Q2 2026. It will handle some run of mine ore, but will mainly process huge waste piles of ore containing hard jaspilite, which has always represented a challenge at S11D. Jaspilite is a hard rock from the Carajas formation containing bands of jasper and iron minerals with 42 % average Fe and 36 % average SiO2. It is challenging due to its high abrasiveness and compressive strength.
According to Vale, it is a 60 m high structure with 84 ° inclination, with more than 5,000 t of steel applied. It has a deep foundation with 583 piles and has involved a huge logistical exercise with more than 17,000 trucks received, with peaks of 100 / day. The project uses an adapted version of Maccaferri’ s Green Terramesh ®, with UV microgrid and a structure resistant to abrasion, salt spray, sun exposure and oxidation. All of this is designed to withstand intense traffic of mining trucks and also ensure safety and durability— with an estimated geogrid lifespan of 120 years.
Metso is the major equipment supplier to the project, including the primary gyratory and two large apron feeders. Other companies involved include civil engineering firm Construtora Barbosa Mello; MCA Auditoria e Gerenciamento, which specialises in consulting, auditing and project management and construction; engineering services group AtkinsRéalis; and project management company Verum Partners.
Takeda told IM:“ Jaspilite in the past has had to be considered as a sterile material and has been stockpiled as it could not be processed efficiently. Vale invested significant resources to come up with a solution for jaspilite. Thanks to the new compact crushing plant, it will now be processed in parallel with the main run of mine material which will mainly use the existing plant. The jaspilite ore will be crushed and classified and then blended with high grade ROM ore to create a new
Reducing wear on the conveyor belt
In a recent article, R. Todd Swinderman, President Emeritus, Martin Engineering says that most conveyor belts in mines and quarries are considered operating in“ severe duty” and typically don’ t just wear out- they’ re exposed to raw material and punishing weather conditions, so more often, they experience a shortened life from catastrophic events, whether it’ s a significant impact, splice failure or piercing damage.“ Or they suffer from chronic issues such as mistracking or frozen idlers. In addition to correcting such problems to extend belt life, a concern to many bulk material handling operations is the damage from loading, belt wear from cleaning devices and the difficulty of cleaning damaged belts.”
Since the belt is a major cost element in the process of conveying bulk materials, much attention is focused on reducing wear and damage. In general, loading wear occurs over a long period of time from the discharge of material onto the belt and from contact with conveyor components such as idlers and belt cleaners. Belt wear from loading includes both impact damage and frictional wear.
“ Damage to the belt can be a single event, such as that from tramp metals or oversized lumps in the material flow stream. Such sudden damage can result in catastrophic failure that requires immediate attention, demanding a system shutdown. The negative effects of long-term wear are less dramatic, and replacement can generally be scheduled for planned outages to avoid affecting conveyor availability.”
One key to understanding belt wear from loading is the chute. The development of Discrete Element Modelling( DEM) as applied to conveyor loading chutes has given the industry a valuable tool for verifying chute designs and predicting conveyor belt wear. A survey of the literature yields evidence indicating belt life improvements of 40-300 % from using DEM to optimise chute designs. The primary objectives of chute design are to direct an uninterrupted flow of the bulk solid from the chute to the receiving belt, centered in the direction of belt travel and as close as possible to the speed of the receiving belt.
While the interaction between the belt and the bulk material is complex, in general, troubleshooting belt wear caused by chute design can take advantage of some simple relationships. The first is the general relationship between material impact angles and the wear rate of rubber.
The second fundamental principal that can be applied to chute design to minimise belt wear is the speed of the bulk material stream, which is affected by friction and acceleration due to gravity as the load falls to the belt. The coefficients of friction between the bulk material, chute and belt are important parameters that are utilised in DEM programs to optimise the shape of the chute, producing the desired exit velocity and direction of the discharged bulk material. Common chute configurations include rock boxes, inclined flat chutes and curved chutes.
Other factors to consider when designing the optimum chute for a given application include drop height and preferred liner materials, but in general, belt wear from the choice of chute design is greatest with rock boxes, which do little to slow the material’ s velocity and introduce a large amount of disruption as the load cascades from one shelf to the next, then lands on the moving belt at a near-perpendicular angle.
Flat inclined chutes help shift the load in the general direction of the receiving belt’ s travel but can involve even greater impacts than a rock box, depending on the drop height. The violent landing takes a constant toll on the belt, often creating significant amounts of fugitive material in the form of dust and spillage.
Belt wear from loading impact is generally minimised when using curved chute designs, as the bulk material stream’ s velocity can be most closely matched to that of the belt with curved chutes.
While belt wear is the main concern, a significant amount of attention should be paid to the selection of liners to prolong chute life. Given the relative cost of the belt compared to the chute in most applications, the wear liners should be considered sacrificial components, and attention would be better spent on improving chute design, selecting lower friction liners and making the liners easier and quicker to change. Some manufacturers have engineered new designs for liners that can be serviced from outside the chute, for example, eliminating the need for confined space entry and drastically reducing replacement time.
78 International Mining | APRIL 2026