COMPUTER SIMULATION OF THE FLOW AND BURNING OF FUELS INJECTED INTO THE BLAST FURNACES’ RACEWAY

PDF | THE INJECTION OF PULVERIZED COAL THROUGH THE TUYERES, COMBINED WITH ADJUSTMENTS TO THE BLAST FURNACE'S OPERATING PARAMETERS, AIMS TO REDUCE THE HOT METAL PRODUCING COST, AS WELL AS IMPROVING THE ENERGY EFFICIENCY OF THE STEELMAKING PROCESS. AUXILIARY FUEL INJECTION WAS ADOPTED AS A METHOD OF REDUCING THE TOTAL AMOUNT OF COKE NEEDED TO OPERATE THE REACTOR. HOWEVER, THE VARIATIONS IN BLAST FURNACE RACEWAY CONDITIONS AND THE FUEL COMBUSTION CHARACTERISTICS, DUE TO THE METHOD AND CONDITIONS OF INJECTION INTO THE REACTOR, ARE STILL NOT FULLY UNDERSTOOD. IN THIS STUDY, THERMOS-FLUID DYNAMIC MODELS WERE DEVELOPED TO SIMULATE THE FLOW OF GASES AND THE COMBUSTION REACTIONS THAT TAKE PLACE INSIDE THE RACEWAY REGION OF USIMINAS' BLAST FURNACE #3. THE RESULTS SHOWED THAT CO-INJECTION OF PULVERIZED COAL WITH NATURAL GAS OR COKE OVEN GAS IS BENEFICIAL IN TERMS OF COMBUSTION PHENOMENA WHEN COMPARED TO THE INJECTION OF SOLID FUEL ALONE. THE MODEL CAN BE USED TO DEFINE THE MINIMUM AND MAXIMUM VOLUME OF GASES TO ACHIEVE OPTIMIZED BURNING DURING INJECTION AND COMBUSTION IN BLAST FURNACES