The pellet plant - ArcelorMittal The pellet plant - ArcelorMittal The pellet plant
Around a third of the iron ore concentrate produced at Mont-Wright and transported to Port-Cartier by rail is transformed onsite into iron oxide pellets. Around one metric ton of concentrate is needed to obtain one metric ton of pellets.
In operation since 1977, the Port-Cartier plant produces pellets day and night, 365 days a year, and employs around 320 people. Initially designed to produce 6 million metric tons of pellets a year, its capacity now exceeds 9 million metric tons, thanks to new technology and, above all to the expertise of our employees to improve the process, as well as the reliability and productivity of equipment. The Port-Cartier plant is considered one of the most efficient in the world.
The pelleting process operates with two production lines and its main stages can be summarised as follows:
- enrichment of the concentrate
- crushing of the concentrate
- filtration
- integration of additives and mixing
- sintering
- sieving
- baking
The plant has enrichment facilities that enable the silica in the concentrate to be reduced if necessary, according to customer requirements for higher quality pellets.
After this optional stage, the concentrate is taken to one of the six grinding balls with water and additives. As they knock together inside the grinders, the balls – made of a very hard alloy – reduce the particles of concentrate to the size of a grain of dust.
The material obtained which resembles mud is pumped to one of the 10 vertical filters for partial drying. After this stage, the substance called filter cake is tipped into one of the three mixers where other additives are incorporated.
This mixture is taken into one of the 10 sintering disks positioned diagonally. These large saucers turn on themselves, forming the pellets with a rotating movement thanks to the centrifugal force and angle of the equipment.
The pellets then move to the sieving section which enables those of the right size to be selected. Pellets that are too large or small are redirected to the disks, while the ones of the right size are sent to the last stage, hardening. To do this, the brittle pellets (also called “green” pellets) are baked in one of the two large furnaces at a temperature of 1300 degrees Celsius.
Around five different pellets are produced at Port-Cartier, each with their own characteristics to meet the specific needs of customers. Particular attention is paid to storage to avoid contamination.