?Luossavaara-Kiirunavaara AB (LKAB), an iron ore company with mines in northern Sweden is continuously considering new technologies for handling, transportation and disposal of waste rock and tailings. The mines and concentration facilities are located north of the Arctic Circle which in Scandinavia means an average temperature of about 0° C. Snow from mid-October to mid-May. In winter the temperature may reach -35 to -40° C during weeklong cold spells. At the Svappavaara mine early technical-economical feasibility considerations together with expected space limitations in the concentrator area favored location of two thickened tailings thickeners on a hill close to the disposal area about 1600 m away from the concentrating plant. In this way only short distance pumping of thickened slurry is required and warm process water is recovered directly by gravity from the thickener to the concentrating plant. A thickener of a high-density type with 18 m diameter was first installed. Four years later an additional thickener of paste type with diameter 24 m was put into operation. The design (maximum) capacities were 115 and 275 tph (tons per hour) for the 18 m and 24 m thickeners, respectively, with solids flux rates of 0.45 and 0.6 ton/m2h. Both are planned for common use for 390 tph within a few years. The tailings product is characterized by an average particle size of about 30 µm with a maximum of about 500 µm and about 40 % passing 20 µm. Solids density about 3000 kg/m3. A solids concentration by mass of 70 % was considered sufficient for deposition at a slope of up to 3 %. The objective is to present and discuss the performance of the thickening, transportation and deposition systems during the commission stages and first years of operation. The aim is also to describe how initial conditions related to changes in the tailings production rate together with climatic conditions called for robust by-pass arrangements. Furthermore, complicating factors related to the choice of auxiliary equipment and instrumentation for central functions are discussed.
The Towards Sustainable Mining Tailings Management Protocol, first released in 2004 and revised in 2011, is used to measure tailings management performance, with five performance indicators focused on: Having a corporate tailings management policy and commitment, Developing and implementing site-specific tailings management systems and emergency preparedness measures, Assigning accountability and responsibility for tailings management, Conducting annual tailings management reviews, Developing and implementing site-specific OMS manuals
Towards Sustainable Mining (TSM) is the Mining Association of Canadas (MAC) commitment to responsible mining. It is a set of tools and indicators to drive performance and ensure that key mining risks are managed responsibly at our members facilities. Adhering to the principles of TSM, our members demonstrate leadership by: Engaging with communities, Driving world-leading environmental practices, Committing to the safety and health of employees and surrounding communities, The program was established in 2004 and its main objective is to enable mining companies to meet societys needs for minerals, metals and energy products in the most socially, economically and environmentally responsible way.