Research on Kinetics of Rich Hydrogen Reduction of Baiyunobo Iron Concentrate Pellets

The wH₂/w_CO ratio on the influence of reduction rate of Baiyun obo iron concentrate pellets was studied by homoiothermy thermogravimetric analysis （TG） method in order to solve the low utilization rate of gas and insufficient supply of heat problems in gas- solid direct reduction process.. The results showed that the reduction rate increases with increasing wH₂/w_CO ratio in 40 minutes after reduction test,and then reduce Fe₂O₃→Fe₃O₄ reaction time. Based on the gas phase diffusion and interface reaction of pellets reduction rate equations the calculated relationship of reaction rate constant and wH₂/w_CO are: k_interface=- 0.197 5 + 0.357 5wH₂/w_CO,k_spread= 0.171 01 + 0.269 7 wH₂/w_CO respectively. The activation energy of the interface reaction and the gas phase diffusion calculated by Arrhenius equation are respectively 26 kJ /mol and 44 kJ /mol,and this indicates that gas diffusion control is a restrictive link under this study condition.