|Cite this article as:|
|Yanbiao Chen, Wenguo Liu, and Haibin Zuo, Phosphorus reduction behavior of high phosphate iron ore during hydrogen-rich sintering, Int. J. Miner. Metall. Mater.,(2021). https://doi.org/10.1007/s12613-021-2385-0|
High-phosphorus iron ore resource is recognized as refractory iron ore because of its high phosphorus content and complex ore phase structure. Therefore, it is of great theoretical and practical significance to develop innovative technology to realize the efficient utilization of high-phosphorus iron ore resources. According to this, a method of phosphorus gasification removal in hydrogen-rich sintering process was proposed. In this paper, the reduction mechanism of phosphorus in hydrogen-rich sintering was studied, as well as the reduction kinetics of apatite based on the non-isothermal kinetic method. The results show that improving the reduction time from 20min to 60min, the dephosphorization rate increases from 10.93% to 29.51%. Companied with the reduction of apatite, the metal iron accumulates, part of the reduced phosphorus gas is absorbed by metal iron to form stable iron-phosphorus compounds, resulting in a great reduction of dephosphorization rate. The reduction of apatite is mainly concentrated in the sinter zone and burning zone, and the reduced phosphorus gas moves downward along with flue gas under suction pressure and is condensed and adsorbed partly by the sintering bed when passing through the drying zone and green mix zoon, as a result, the dephosphorization rate is greatly reduced. Based on the Ozawa formula of iso-conversion rate, the reduction activation energy of apatite is 80.42 kJ/mol. The mechanism function of apatite reduction is determined by differential method (Freeman-Carroll method) and integral method (Coats-Redfern method). The differential form of the equation is f(a)= 2(1-a)1/2, and the integral form is G(a)= 1-(1-a)1/2.