Simulation Analysis of Coal Packed Bed Type Smelting Reduction Process

Abstract

The simulation analysis of material and heat flow in coal packed bed type smelting reduction process, such as COREX process, was conducted by use of the computer model developed based on the heat and material balance. The simulation was conducted by focusing on the amount of volatile material in coal used in the process and the operation condition of the fluidized bed melter gasifier where the reducing gas used in the reduction shaft is generated. The coal consumption decreases with decrease amount of the volatile material in coal. By increasing the oxidation degree of off-gas from the fluidized bed melter gasifier, the coal consumption decreases but the increasing amount is limited by the requirements of reduction shaft. The simulation results show that it is important for efficient process to control the volume and temperature of off-gas from the fluidized melter gasifier to be matched with the requirement of reduction shaft, which is necessary for reducing the amount of gas scrubbed and cooled as much as possible. It can be accomplished by using the low volatile coal and by increasing the oxidation degree of off-gas from the fluidized melter gasifier within the allowable range.