The amount of phosphorus associated with iron ores, in few of our mines, is quite sporadic and high, which causes problems in downstream processes of iron and steel making. The Phosphorus content in iron ore ranges from 0.10% to 0.30%. At some places, it’s as high as 0.40% - 0.50% level or even more.
Detrimental effects of high phosphorus content in steel include various forms of embrittlement which reduce the toughness and ductility. Lower the phosphorus content in iron ore, better it is for iron and steel quality. We desire to achieve < 0.05% phosphorus content in iron ore.
The phosphorus content in iron ores is determined by chemical analysis (through ICP-OES analytical instrument at in-house Laboratory) of down-hole samples collected from exploratory drilling work spaced mostly at 100m x 100m grid. Phosphorus content determined from exploratory drilling work and ore samples collected from blast holes is used in grade control processes.
Existing facilities of ore processing at mines, do not have the capability to reduce phosphorus level from run-off mine (ROM) ore to product to that extent during wet processing or beneficiation of ore. In the existing process, the reduction (ROM ore to product) level is normally less than 10%. Therefore, ores are blended in controlled proportion with low phosphorus ores to minimize and average out the impact of high phosphorus iron ore in the downstream iron and steel making processes. The downstream processes require ores with Phosphorus content as low as possible, preferably at 0.085% to 0.10%.
The solution should fulfill the following requirements: