| This article investigated autothermal reformer based on the back ground of Coke Oven Gas autothermal reforming technology. Flow field and reaction characteristics of autothermal reformer were studied by experiment and numerical simulation. Moreover, the process simulation was investigated using Aspen Plus. The detail contents are as follow:(1) The flow characteristics of autothermal reformer were investigated by experiments and numerical simulation. From the analysis results of flow field, space in the autothermal reformer can be divided into two parts:combustion chamber and catalyst bed. The flow in combustion chamber can be characterized by velocity distribution, turbulence intensity and reflux ratio. Results showed that the velocity distribution and turbulence intensity in chamber upper part were not influenced by catalyst bed height and porosity, but turbulent intensity increased with inlet flow rate. The axial velocity of chamber bottom part was increased with catalyst bed height, porosity and inlet flow rate. The turbulence intensity of chamber bottom part was increased with catalyst bed height and inlet flow rate. The reflux ratio in chamber was not influenced by inlet flow rate.The flow in catalyst bed can be characterized by maldistribution factor and penetration depth. The maldistribution factor was decreased with catalyst bed porosity, while penetration depth was increased with catalyst bed height. The uniform distribution characteristic of autothermal reformer was not influenced by inlet flow rate.(2) Resident time distribution of autothermal reformer was studied by impulse response. The influences of catalyst bed height and inlet flow rate on RTD were analyzed. The results showed that the mean residence time, variance residence time decreased as well as distribution functions of RTD narrowing with the catalyst bed height increasing. The mean residence time decreasing and dimensionless variance residence time increasing with inlet flow rate increasing. The RTD model was formed by combination with CSTR, axial dispersion model and PFR based on the flow characteristic of autothermal reformer. Parameters in model were obtained by Laplace transforming and Levenberg-Marquardt.(3) The characteristic of co-axial jet free diffusion flame of Coke-Oven Gas (COG) was investigated by experiments. The results showed that the flame length was increased with COG flow rate and Froude number (Frf). In the zone of momentum control, the relationship of flame length and Frf is linear:L=137.07Frf-B. The flame length was increased with Re. when the Re is larger than 8×104～9×104, the flame length was constant. The relationship of Frf and Re was linear. When the jet velocity of COG is 20 m/s, flame will be blown off. The height of blow off had a proportional increasing to jet velocity. Flame will be extinct when the velocity of COG larger than 100m/s.(4) The influences of feed on syngas composition were studied. Results showed that when flow rate of oxygen was constant, the fractions of H2, CO, CH4 in syngas were increased at first and then decreased with COG flow rate increasing. While methane conversion and CO2 fraction are decreased with COG flow rate increasing. When COG flow rate is constant, CH4 concentrations of outlet was decreased with oxygen flow rate increasing, while CO, CO2 and H2 concentrations of outlet were increasing at first and then constant with oxygen flow rate.(5) The reactions and flow in autothermal reformer were investigated with the numerical simulation. The structure and characteristic of flow field of hot model were analyzed. The influences of operation pressure and swirl number of nozzle on flow field, and the influences of steam/fuel and oxygen/fuel on methane conversion and H2+CO yield were studied. Results showed that the attenuation of swirl velocity is slow than axial velocity. There was back flow zone near the axis area. Along the radial position, the swirl velocity increase at first and then decreased. The peak value of swirl velocity is at central position of back flow zone in chamber. Temperature and concentration gradient of chamber is larger than that of catalyst bed. Operating pressure and large swirl number is good for the species mixing. From the analysis of conversion and effective gas (H2+CO) yield, it can obtain the optimal value of Steam/COG and Oxygen/COG is 0.1～0.2 (kg/Nm3) and 0.15～0.2 (Nm3/Nm3), respectively.(6) Autothermal process simulation was studied with Aspen Plus. The influences of operating pressure, feed composition, Steam/COG and Oxygen/COG on syngas composition were investigated. Results showed that methane conversion and effective gas yield are decreased with the operating pressure. There is no any effect of CO2 fraction in feed on methane conversion, but effective gas yield is increased with CO2 fraction in feed. The Steam/ COG could not affect methane conversion and effective gas. Methane conversion is increased with Oxygen/COG, while effective gas yield is decreased with increasing of Oxygen/COG.
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