Improving aggregate plant capacity with screen replacement

Rudus Oy, part of the international CRH group, produces a range of aggregate products at its Kulmakorpi quarry in Espoo, Finland. The products are both for the concrete and construction industry as well as for private customers. 

At the Kulmakorpi site, Rudus excavates the rocks to produce aggregates and the city of Espoo then utilizes the excavated area to landfill topsoil from building construction sites. One area has already been excavated and is in the process of being filled, and Rudus is moving the equipment to a new spot in less than a year.  

Removing bottleneck in crushing process 

In 2017, the entire crushing process at Kulmakorpi was analyzed in terms of capacity and throughput in a Metso SiteBooster™ plant optimization project. Rudus discovered that their current Metso FS302 screen was no longer meeting the capacity targets of the crushing process and was instead creating a bottleneck in the overall production process. 

Metso’s solution was to replace the current screen with a complete Metso Nordplant™ screen module consisting of a Metso ES402™ horizontal screen and a new steel structure designed and implemented by Metso. The installation took place in autumn 2018 and Rudus is satisfied with the capacity increase, which has helped them to meet their targets. 

“The ES402 screen has significantly higher capacity than the FS302. It is also easier to maintain as there is a large space between the decks for screening media changes, and the greasing points are located in places where greasing is safe and easy to carry out,” says Kimmo Leppikangas, Production and Development Manager at Rudus Oy.  

Developing crushing technology together to increase production 

The crushing process consists of four stages: a portable NW125™ jaw crusher in the primary stage, the NWGP500S™ and a Metso ES402 horizontal screen in the secondary stage, and two individual tertiary production lines with NWGP500™ cone crushers and FS353 screens. All the equipment, with the exception of the new Metso ES402, is mounted on wheels so that it can be moved between sites with a standard truck and set up quickly without concrete foundations or a steel structure.  

“Rudus and Metso share decades of partnership and have also developed crushing technology together. Prototypes of the C-Series jaw crushers and MX multi-action crushers were tested on Rudus’s Kulmakorpi site,” says Juha Tiilikka, Sales Manager at Metso.  

“This kind of investment decision doesn’t happen overnight. It’s good to see how our reports and simulations help customers to make future investment decisions and plans, as well as support internal communication,” explains Tiilikka.  

Rudus and Metso will continue their close co-operation in the future. “Currently we have several development projects ongoing with Metso where the target is to increase production on different sites and to identify bottlenecks,” confirms Leppikangas.