Papers by Author: Yong Sheng Sun

Abstract: The changing characteristics of iron mineral along with the reduction time in reduction of a high phosphorus oolitic hematite by carbon were discussed in the paper. The grain growth of metallic iron was investigated in detail. The results showed that the iron mineral in reduction of the oolitic hematite changed as Fe₂O₃→Fe₃O₄→FeO→Fe, and finally was reduced to metallic iron. As the reduction time elongated, the small grain of metallic iron gathered toward the larger one and grew up. The metallic iron existed in the reduction products in the form of larger grains of metallic iron.

Abstract: The composition of Deoxidized Samples of Bayan Obo Oxidized Iron Ore is complex with high content of residual reducing C, Fe phase in the RDP is ferrous metal what is hard and malleable resulting in pessimistic grindability. Gravity-magnetic separation process flow is adopted with C pre-rejecting, stage grinding (-0.074mm -57.18%, -0.074mm -85.66%) and coarse-fine fraction separate treatment base on RDP process characteristic. The final concentrate has 92.02% Fe with 93.27% Fe recovery, 94.18% Fe metallization which may utilize as rough materials for steelmaking and the final tailings has 15.10% REO with 97.15% REO recovery which may utilize as rough materials for REO concentration.

Abstract: Occurrence state of rare earth elements in the different deoxidization stages and the behavior of rare earth elements in the process of depth reduction were studied by analyzing XRD and SEM images of Bayan Obo oxide ore in different deoxidization time. The results showed that deoxidization time had a great effect on the occurrence state of rare earth elements. With the increase of deoxidization time, rare earth minerals gradually translated from bastnaesite and urdite into (CaO•2Ce2O3•3SiO2).This phase was white with a small size. It was columnar or massive in most cases and could be easily separated from the iron phase. 97.18% of the rare earth elements, which could be recovered by flotation, gravity separation and magnetic separation, entered the iron tailings.

Abstract: The diatomite-cellulose composite fiber (DCCF) was used to modify the asphalt for pavement, and then the DCCF-modified asphalt was researched by DSC from the point of congeries state and energy change, the temperature and heat absorption of the phase transition as index, combined with the macro-road performance of asphalt. The results showed that the high/low-temperature performance and temperature susceptibility of the DCCF-modified asphalt were all improved obviously and would be the best if the modifier dosage was 0.5%. DSC could effectively explain the influence of DCCF on the properties of asphalt from the view point of congeries state and energy change, and the variation were consistent with the Macro-mechanical properties test results of the modified asphalt.