مدل سازي و بررسي افزايش توليد و كاهش مصرف انرژي درتهيه گندله در صنايع فولاد

Mathematical Model for Energy Saving and Increase of Pellets Production in the Steel Industry

Mathematical model for a pilot scale iron ore pellet induration furnace has been developed which considers the process ofʹ induration including the reactions of limestone, magnetite and carbon. The differential equations of energy, mass and momentum were solved simultaneously. The profiles of temperature, pressure and concentration were obtained. The validity of the model has been checked by performing separate experiments on sub processes such as drying, firing and cooling. At first, a mixture of iron ore was selected and then the percentage of lime stone was changed. The maximum metallization and fired pellet strength with minimum sticking vs. basicity was obtained. In the next stage the percentage of carbon in iron ore is altered and all of physical and chemical property of the pellets was measured. Finally, the optimum percentage of carbon in the iron ore was determined. By using different percentage of carbon in the pellet the experiments were performed in three conditions. In the first condition, inlet gas temperature was decreased alone. In the second condition, inlet gas temperature and total indurations time were decreased together and in the third condition, in addition to above conditions; oxygen injection to the furnace was carried out. Energy savings in all three conditions have been obtained.