Oxidation induration process and kinetics of Hongge vanadium titanium-bearing magnetite pellets

Abstract

The induration process and oxidation kinetics of Hongge vanadium titanium-bearing magnetite (HVTM) pellets have been investigated by employing X-ray diffraction, scanning electron microscope, energy-dispersive spectroscopy, thermogravimetric and differential thermal analysis and thermogravimetric and differential scanning calorimetry. The results indicated that HVTM was a high-chromium vanadium-bearing titanomagnetite containing 1.48 wt-% Cr 2 O 3 , and the crystal stock strength was 625 N. The compressive strength of HVTM pellets could be improved by increasing the roasting temperature and roasting time. Under the optimum conditions of oxidation roasting at 1200°C for 15 min, the compressive strength was found to be 2893 N. The phase transformations of the valuable elements could be described as follows:

Innovative methodology for recovering titanium and chromium from a raw ilmenite concentrate by magnetic separation after modifying magnetic properties

“…In addition, it was calculated that the ratio of Fe 2+ to total iron was in the range of 0.27-0.39, suggesting that the reasonable oxidation extent of the ilmenite for improving magnetic susceptibility was about 65%. Although there was 12.7% of V-Ti-bearing magnetite in the raw sample, few of them reported the magnetic separation concentrate due to its nature of easier oxidation [21,22]. So the content of Fe 2+ was mainly responsible for the ilmenite.…”

Non-isothermal Reduction Behavior and Mechanism of Hongge Vanadium Titanomagnetite Pellet with Simulated Shaft Furnace Gases

“…The green pellets produced were dried at 105°C in an oven for 5 h and roasted in a muffle furnace at a roasting temperature of 1 200°C for 15 min according to our previous study. 28) The average compressive strength of HVTMP was 2 893 N. The particle diameter and weight of HVTMP were about 11.3 mm and 3.1 g on average, respectively. The chemical composition and X-ray diffraction (XRD) patterns of HVTMP are shown in Table 1 The total content of H 2 and CO studied in the present study is about 90%, but the ratio of φ(H 2 ) to φ(CO) differs widely.…”

Influence of Cr₂O₃ Addition on the Gas-Based Direct Reduction Behavior of Hongge Vanadium Titanomagnetite Pellet with Simulated Shaft Furnace Gases

“…The roasting temperature and time were set to 1 200°C and 20 min, respectively. 24) Eventually, the roasted pellets were removed from the furnace and cooled to room temperature in the absence of air.…”

“…22) Numerous studies on the gas-based direct reduction of HVTM or VTM were carried out. [23][24][25][26][27][28][29] Li et al 23) investigated the correlations between roasting characteristics of HVTMP and its subsequent reduction behaviors. Pan et al 27) studied the reduction behavior of raw and oxidized VTM in a bubbling fluidized bed.…”