Heat transfer modeling during production of directly reduced iron (DRI) pellets by simulating tunnel kiln condition

Recently CSIR-NML has developed a process for production of Directly Reduced Iron (DRI) utilizing lean grade raw material in Tunnel Kiln. It was observed that the heat transfer across the bed of crucible plays a vital role to ensure the uniform metallization throughout the bed of crucible. Therefore, an attempt has been made in the present investigation to develop a mathematical model to predict the thermal profile across the cross section of the bed of crucible using Finite Volume Method (FVM) during production of DRI by simulating tunnel kiln conditions. The developed model was validated with experimentally obtained results. The mathematical model so developed can be extended to a commercial tunnel kiln process for prediction of thermal profile across the bed of crucible as well as kiln during production of DRI.