MMK reuses iron-bearing waste
The line is currently being assembled for further industrial use. The annual economic benefit of using 75,000 tonnes of oiled cinder will amount to RUB 63.2 million, and the project payback period will not exceed one year.
Until recently, MMK had not used oiled cinder, unlike dry cinder, which is made up of 72% iron and is traditionally good iron-ore material for sintering. Increased liquid content and build-up of oil had not allowed this material to average when joined with other iron-ore materials at MMK. Throughout 2015, the mill accumulated 46,000 tonnes of oiled cinder with an average iron content of 67.5% and liquid content of up to 12%.
During laboratory and industrial research nonmagnetic material cut between 0-10 mm proved the most suitable for combination with cinder material as it proved most effective in slag treatment, improving the fluidity of the final mixture. Nonmagnetic product additionally contains 23-25% iron, which also lends itself to use in the sintering process.
MMK ore-dressing mill’s unloaded power vacuum filtration units (VFU) were used to merge these metals. An average iron ore mixture of oiled cinder and nonmagnetic fractions was prepared. After several experiments with VFU in the drying barrel, material suitable for sintering with a total iron content of 50.8% was produced.
Thanks to using this mixture in the sinter burden, it is now possible to return to production over 50,000 tonnes of iron from oiled cinder and 6,600 tonnes of iron from nonmagnetic fractions of 0-10 mm per year. This project is particularly important from an environmental point of view, as it ends the need to accumulate oiled cinder in the Eastern and Western pits of Magnitnaya Mountain, which will improve the state of the environment in Magnitogorsk.