PERFORMANCE OF TWIN OXYGEN-COAL LANCES FOR PCI OPERATION IN BLAST FURNACE IRON MAKING

摘要

A three-dimensional multi-phase model with Discrete Particle Model (DPM) approach has been developed to examine the performance of the twin oxygen-coal lances for PCl operation. Simulation conditions and properties of the PC were obtained from the real operation conditions of the blast furnace of 580 m~3 with molten iron output of 1775 t/d. The simulation results of novel PCI style were also compared with the results of conventional PCl operation. Results show that the twin coal-oxygen lances changed the gas flow pattern near the tuyere, which results in a different mixing and burning process of the pulverized coal. The coal combustion efficiency near tuyere could be improved by applying coal-oxygen lance. For the PC adopted in the simulation, coal BR at the exit of the simulation region increased from 30% to 60% and the maximum temperature of the gas phase increased from 2200K to 2600K by applying the twin coal-oxygen lances and the high temperature zone is in a safe distance from the nozzle.