Pelletization of Malaysia magnetite concentrates and its properties of gas-based direct reduction

摘要

Direct reduction pellet production has become one of the hot spots developments, and the production of high quality pellets is an important guarantee. In this research, the pelletizing behaviors of one Malaysia magnetite concentrates was studied, including the effect of induration parameters and different basicity on the strength of pellets. Then the correlation between pellets basicity and properties of gas-based direct reduction by HYL process was investigated. The results show that the compressive strength of product pellets can reach over 2500 Newton per pellet while the green pellets made of Malaysia magnetite concentrates are preheated at 800°C for 7min and fired at 1250°C for l0min respectively, and with the increase of basicity, the strength of product pellets increased significantly. In addition, product pellets with nature basicity had superior mineral compositions and microstructure, and the product pellets possess good direct reduction performance which have good reducibility, lower swelling index of only 4.53%, and lower temperature disintegration (RDI_(-3.15)mm only 8.24%). This kind of Malaysia magnetite concentrates is suitable as pellet feed and meet the demands of gas-based direct reduction by HYL process.