What happens in Kiruna?

Published 2011-12-07 00:00:00

The answer is: quite a lot! The ore industry is larger than ever and to excavate new shafts, drifts and extract the ore, enormous amounts of shotcrete is required. Sika supplies the additives.

The iron ore is a gold mine

Modern mining is profitable. The demands for ore, and consequently the prices, are on levels never seen before. The development in countries like China has given the world’s steel production a powerful push and a lot of factors indicate that the strong demand will continue.
In order to increase the production capacity, LKAB makes major investments in the iron ore operations in Kiruna and Malmberget. On both locations, new pellets and concentration plants have been built and there has also been a significant expansion in the logistics chain.

Down to new levels

In pace with the extraction of the ore bodies, new main levels have to be constructed to allow continued mining at deeper levels. The current main production in Kiruna takes place at 1,045 meters. When that level was built, it was estimated that it would last at least until year 2015. However, because of the increased production rate, the next main level has to be finalized earlier than expected. Studies for a location at 1,365 meters, are in progress. Based on the current plans, this will be operational by year 2013. In Malmberget, the current main level is today at 1,000 meters and there are plans for a new level at 1,250 meters.

High early strength

- Major rock work is required and it takes many drifts and transport routes to get there. Everything has to be secured, which involves enormous volumes of shotcrete, Thomas Cederhammar, Business Unit Manager of BU Concrete at Sika Sweden, says.
The shotcrete is sprayed onto the surface at high pressure and with the addition of an accelerator. The accelerator increases the speed with which the shotcrete develops strength and makes the concrete stick to the wall. In order to keep up the production rate without compromising safety, it is important that the shotcrete develops a high early strength.

Environment and efficiency

As main supplier of both shotcrete accelerators and plasticizers, Sika is an important cog in the large machinery around efficient and environmentally sound operations. Among other things, Sika contributes with important knowledge in processes where crushed rock is used in the concrete, like in Malmfälten. Sika can with its additives and mix design competence achieve the shotcrete characteristics that are important for both execution and construction, while taking the environment into account. Deliveries to Malmfälten are mainly made by train to limit emissions. Since the volumes are so large, Sika’s total production is significantly affected.

Secured delivery capacity

In order to meet their responsibilities as supplier and guarantee full capacity, Sika has chosen to set up storage tanks on site, both in Malmberget and in Kiruna.

- We take full responsibility for the performance of our products and to be available whenever they are needed in the process, Tomas Cederhammar says.

Future in Malmfälten

Everything points at a continued hot market for the Swedish iron ore. A comprehensive inventory of the existing ore bodies and how they extend is in progress. The future mining will affect both buildings and people in Kiruna and Malmberget and the urban transformation has already started.