The effect of nickel oxide additive on the smelting behaviors of chromium-bearing vanadium titanomagnetite pellets(CVTP)was investigated while analyzing the transfer behavior of nickel in iron and slag.The results sho...The effect of nickel oxide additive on the smelting behaviors of chromium-bearing vanadium titanomagnetite pellets(CVTP)was investigated while analyzing the transfer behavior of nickel in iron and slag.The results show that when NiO added to CVTP increases from 0 to 6 wt.%,softening start temperature increases from 1148 to 1212℃,and the softening end temperature increases from 1280 to 1334℃;the melting start temperature increases from 1318 to 1377℃,and the dripping temperature decreases from 1558 to 1521℃.The pig iron comprises a compound of Fe-Ni-C.The slag structure depolymerizes with increasing nickel addition.The softening-melting behaviors of CVTP,the reduction of nickel into pig iron,and the depolymerization of slag structure indicate the feasibility of producing nickel-iron alloy through the blast furnace process.展开更多
Pilot experiments on Na;SO;-roasting of V-Ti magnetite(VTM) concentrate pellets were performed to activate vanadium with simulated grate-kiln machines. Combined with thermodynamic calculation, X-ray diffraction(XRD), ...Pilot experiments on Na;SO;-roasting of V-Ti magnetite(VTM) concentrate pellets were performed to activate vanadium with simulated grate-kiln machines. Combined with thermodynamic calculation, X-ray diffraction(XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS), and inductively coupled plasma-atomic emission spectrometry(ICP-AES) analyses, process parameters of pellet making were optimized, and the enhancement of vanadium oxidation and conversion was realized. The results show that, in balling stage, adding Na;SO;can promote the thermal decrepitation resistance of green pellets;in the drying stage, higher wind temperature can improve the dispersion of sodium salt in pellets;in preheating stage, using O;-rich hot gas can promote more thorough oxidation of vanadium;in roasting stage, the effect of vanadium conversion to sodium vanadate is better when the liquid amount is 15.5%-22.5%. Based on the above measures, the vanadium conversion rate achieved in the roasted pellets is 85.6%, proving the feasibility of vanadium recovery using an existing pellet production line.展开更多
基金financial supports from the National Natural Science Foundation of China(Nos.21908020,U1908226)。
文摘The effect of nickel oxide additive on the smelting behaviors of chromium-bearing vanadium titanomagnetite pellets(CVTP)was investigated while analyzing the transfer behavior of nickel in iron and slag.The results show that when NiO added to CVTP increases from 0 to 6 wt.%,softening start temperature increases from 1148 to 1212℃,and the softening end temperature increases from 1280 to 1334℃;the melting start temperature increases from 1318 to 1377℃,and the dripping temperature decreases from 1558 to 1521℃.The pig iron comprises a compound of Fe-Ni-C.The slag structure depolymerizes with increasing nickel addition.The softening-melting behaviors of CVTP,the reduction of nickel into pig iron,and the depolymerization of slag structure indicate the feasibility of producing nickel-iron alloy through the blast furnace process.
基金financially supported by the Science and Technology Innovation Program of Hunan Province, China (No. 2021RC2003)the National Natural Science Foundation of China (No. 72088101)China Postdoctoral Science Foundation (No. 2021TQ0370)。
文摘Pilot experiments on Na;SO;-roasting of V-Ti magnetite(VTM) concentrate pellets were performed to activate vanadium with simulated grate-kiln machines. Combined with thermodynamic calculation, X-ray diffraction(XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS), and inductively coupled plasma-atomic emission spectrometry(ICP-AES) analyses, process parameters of pellet making were optimized, and the enhancement of vanadium oxidation and conversion was realized. The results show that, in balling stage, adding Na;SO;can promote the thermal decrepitation resistance of green pellets;in the drying stage, higher wind temperature can improve the dispersion of sodium salt in pellets;in preheating stage, using O;-rich hot gas can promote more thorough oxidation of vanadium;in roasting stage, the effect of vanadium conversion to sodium vanadate is better when the liquid amount is 15.5%-22.5%. Based on the above measures, the vanadium conversion rate achieved in the roasted pellets is 85.6%, proving the feasibility of vanadium recovery using an existing pellet production line.
