In FASTMET process, solid-gas heterogeneous reactions, such as reduction of hematite to magnetite, magnetite to wustite, wustite to iron and carbon to carbon-monoxide among reactants are possible. In this research these reactions in a packed bed are studied. Most researchers have pursued one-dimensional mathematical models to predict the reduction process. Due to extreme effects of temperature on the reduction process, the degree of reduction in cases with temperature profiles across the bed is considered in the present study. Therefore, the main goal of this study is to evaluate the effects of a 2D temperature field on the degree of reduction. In this research a bed containing magnetite and coal particles is modelled and numerically simulated. An unsteady and axisymmetric model for a cylindrical bed is presented and the governing equations are solved by adding the necessary macros in the FLUENT code. The simulated bed is heated by an electric furnace. The present study investigates the effect of volatile species of coal on reactions, the effect of mass fraction distribution of species on reaction rates, factors affecting heat transfer, comparing convective and diffusive flux and oxygen fraction of iron oxides. Gas species such as CO and CO2 released from coal are agents for initiating the reduction process. Magnetite reduction to wustite appears to be more progressive than other reactions, because it is less sensitive to temperature, so CO is produced at high temperatures. The generated carbon monoxide is diffused to the location with less temperature, due to concentration gradients. The diffusive flux profile comprises two extremum points at different times because of high consumption rate of CO. Between these two points, the traort mechanism is mainly due to convection and the diffusive flux is less than convection flux. Therefore, it can be concluded that both convection and diffusion are important in CO traort. Reaction rate increases with increasing CO pressure that contributes to formation of wustite and iron. Increasing the amount of wustite decreases thermal conductivity, whereas increasing the amount of iron increases the conductivity. In this study, the rate and concentration of solid species such as magnetite, wustite and iron along the bed are determined, and oxygen fraction of iron oxides at different radial locations have been calculated based on these rates. Due to the existence of temperature profile in radial direction, oxygen fraction of iron oxides shows more than 50 percent difference between radial location of 0 and 25 mm. This shows that, one and two dimensional solutions under non-symmetrical thermal boundary conditions could produce predictions with significant differences. Moreover, in this work, a rotary hearth furnace is simulated to find out the temperature distribution in such bed. Because of non-uniform distribution of radiation and convection heat flux in furnace, a temperature difference of 90 K in the first reduction zone is obtained. Consequently, due to significant effects of temperature change on oxygen fraction of iron oxides, two-dimensional models is considered suitable in rotary hearth furnace modeling. Keywords: FASTMET Process, Direct Reduction, Rotary Hearth Furnace, Oxygen Fraction of Iron Oxides and Radiation.