Despite Boliden’s Kylylahti copper mine having an estimated lifetime of only four years left, it paid off for the concentration plant to upgrade its jaw and cone crushers from the 1960s to Metso’s latest models in a speedy installation process.
Crusher upgrades cut the cost of wear parts for Boliden Kylylahti’s crushing operations at the Luikonlahti concentration plant
“Together with Metso we calculated that the new C130 jaw crusher and GP330 cone crusher were a good investment for us. With our abrasive ore, they will help us cut our crusher spare parts costs. The savings will have a noticeable impact on our entire mine’s unit costs,” estimates Janne Laukkanen, Boliden’s Luikonlahti concentration plant Milling manager.
According to Timo Kaariaho, Maintenance manager, the new crushers will help the mine to ensure continuous, reliable operations and improved maintenance safety.
“Due to the ore’s abrasive wear, the crusher settings must be adjusted often, and in the old crushers, this had to be done manually. With Metso’s new models, the settings can be controlled quickly and safely thanks to a hydraulic adjustment system. Even single wear parts can be changed more quickly,” explains Kaariaho.
Speedy crusher upgrade
From investment decision to installation at Boliden Kylylahti’s concentration plant, the entire crusher upgrade project took just a little over three months, and the actual installation took four days. Metso Minerals’ Sales manager for southern Finland, Timo Sarvijärvi, made the profitability calculations of the upgrade for the mine.
Metso’s Tampere plant manufactured the crushers in two months. The actual installation work took just four days and was able to be carried out in conjunction with the changing of the mill lining.
At the end of the week, Boliden’s crew dismantled the old Lokomo MK120C jaw crusher and the Ernest Thällman 5½-foot cone crusher that was manufactured in East Germany. On Sunday evening, Metso’s 6-strong installation team stepped into action on the work site.
After the crusher foundations were finished, the roughly 40-ton C130 jaw crusher and feed hopper were lifted using a mobile crane and shifted into place in the primary crushing plant, which is located on a slope. The 15-ton GP330 cone crusher used for fine crushing was lifted into the crushing plant in two pieces.
On Tuesday, Metso completed all of its main work related to the crusher installation. Boliden took care of the electrical work and connected the crushers to the feed and conveyor systems.
Crushers started up on Wednesday, production on Friday
By Wednesday, the concentration plant was already able to test out the crushers, and by Thursday the power was connected and the first ore blocks were fed into the process. Actual production began right on schedule on Friday morning.
At the Luikonlahti concentration plant, copper ore from Polvijärvi is crushed weekdays from 6 a.m. until 10 p.m. The C130 jaw is set at 100–120 mm and it crushes some 250 tons per hour.
The ore is crushed into finer particles with secondary and tertiary (GP330) cone crusher, aiming to achieve 10mm particle size. Due to the abrasive nature of the ore, the GP330 has more options to optimize wear parts and get savings from it.
Smaller ore particles for grinding
Concentration Plant Manager Janne Laukkanen’s goal is to achieve smaller particles than before for grinding with Metso’s new GP330 fine crusher.
“With the old crushers, the size of the ore particles heading for grinding was 12 mm, and we now want to reduce that to 10 mm. Thanks to the smaller mill particle size, we can reduce our comminution costs and also lower our electricity costs somewhat in crushing,” says Laukkanen.
The Boliden Kylylahti concentration plant currently processes 750,000 tons of ore a year. The ore contains around 1.4% copper, 1.0 g/t of gold and 0.6% zinc. The plant produces copper and zinc concentrates. The concentrates are used by the company’s own plants – copper concentrate is used at the Harjavalta smelter and zinc concentrate at the Kokkola smelter.
“The production volumes will remain the same, even though the new crushers would allow us to increase our capacity if need be. New mineral resources are explored all the time, and Boliden is, in fact, an active ore explorer in Finland,” says Laukkanen.
*Metso Outotec was formed July 1, 2020 when Metso and Outotec merged into one company. This case study has been written prior to the merger under the old company name.