Abstract— The present work deals with utilization of heat associated with the waste gas which is generated during the operation in the coal based sponge iron plant. Utilizing this heat in the process may reduce the coal consumption which is the only source of energy for this plant. Heat integration is applied on the actual plant data to utilize the heat associated with waste gas exiting from ESP. This is done by pre-heating the feed material by gas solid fluidized bed dryer. The two-dimensional nonreactive gas–solid fluidized dryer is designed by applying computational fluid dynamics in order to investigate hydrodynamic and heat transfer phenomena. A multi fluid Eulerian model incorporating the kinetic theory for solid particles is applied to simulate the unsteady state behavior of this dryer. This reduces the amount of coal consumption. In addition, to decrease in the amount of air the waste gas amount is also decreased. Keywords—Sponge iron plant, gas–solid fluidized dryer, computational fluid dynamic, Eulerian model. I. INTRODUCTION PONGE iron is the metallic form of iron produced from direct reduction of iron oxide below the fusion temperature of iron ore (1535ºC) utilizing hydrocarbon gases or carbonaceous fuels such as coal. The reduced product having high degree of metallization exhibits a honeycomb structure due to which it is named as sponge iron. Sponge iron is produced primarily both by using non-coking coal and natural gas as reductant and therefore classified as coal based and gas based processes, respectively. Due to a promising availability of coal, the coal based sponge iron plants share the major amount of its production in India. There exists a large scope to apply modern technology to this industry to reduce the loss of heat generated in the process is lost without being recovered and to make it more competitive by cutting down its internal losses. The present study utilizes the above opportunity effectively and puts forward suggestions to improve the energy efficiency of the industry through design modifications. Deepti Tirumalaraju is with the Department of Chemical Engineering, National Institute of Technology, Rourkela, Odisha 769008 India. Abanti sahoo is with the Department of Chemical Engineering, National Institute of Technology, Rourkela, Odisha 769008. Shabina khanam is with the Department of Chemical Engineering, Indian Institute of Technology, Roorkee, Uttrakhand. Many investigators such as Agrawal et al., Rani Devi and Mazumder, and Misra and Ipicol considered the process of sponge iron manufacturing and recommended improvement in that [1]-[4]. It is found that during the operation in the coal based sponge iron plant, an incredible amount of heat is generated and a significant part of this heat associated with the waste gas, remains unutilized. A few authors considered this fact and suggested improvement in the process Prasad et al. investigated the utilization of heat of waste gas, through two case studies considering preheating of feed material [5]. They compared these cases with the existing waste heat recovery system of the plant based on coal consumption and economic analysis. The literature indicates that for Indian sponge iron industries the power consumption ranges from 45-130 kWh/t [6]. Significant improvements in decreasing energy consumption were achieved in gas based direct reduction processes. However, for coal based processes potential for such savings is required. Although many plants have acquired the desired level of operational efficiency but from energy point of view various units is below optimum limit. The principal cost factor in direct reduction is energy cost as energy requirement for rotary kiln processes ranges between 14.63 GJ/t to 20.9 GJ/t [7]. Based on above discussion, it was observed that for heat recovery several authors have considered only heat available with waste gas; however, in the sponge iron process there are many potential areas where unutilized heat is present. Therefore, a fresh look is required on the existing process to integrate energy effectively. In the present study, CFD simulation model is used for investigation of hydrodynamic and heat transfer during drying process. An Eulerian multi fluid model incorporating the kinetic theory for solid particles is applied to simulate the unsteady state behavior of this dryer. II. DESCRIPTION OF CONVECTIONAL COAL BASED SPONGE IRON PLANT The process flow sheet of a typical coal-based sponge iron plant with material and energy balanced operating data is shown in the figure. 1. The overall production capacity of the plant is 100tpd. In this process screened iron ore (6.5tph), coal (3.529tph) and dolomite (0.2tph) are charged into the rotary kiln. About 40% of total 5.958 tph coal i.e 2.429tph of slinger Simulation of Fluidized Bed Dryer using CFD for Preheating of Feed Material in Sponge Iron Plant Deepti Tirumalaraju, Abanti Sahoo, and Shabina Khanam S International Conference on challenges in IT, Engineering and Technology (ICCIET’2014) July 17-18, 2014 Phuket (Thailand) http://dx.doi.org/10.15242/IIE.E0714019 95