| Along with the progress of the ironmaking techniques by blast furnace in our country, high iron grade charges are loaded for the BF, resulting in the higher productivity and coal injection rate lower coke ratio and BF slag. But with the increase in iron grade and the decrease of SiO2 the quality of the finished sinter including the mechanical strength RDI RI will deteriate, which can be cured by the production of sinter at high or even super-high basicity. The basicity of sinter, however, has to be limited to the range from 1.6 to 1.8 in most ironmaking plants because of the shortage of acid charges in China. So it is difficult to improve the sinter quality and increase yield of sinter with 4.0%4.5% SiO2 content at 1.6-1.8 basicity.The sinter containing 58%-62% iron and 4.0%-4.5% SiO2 was produced by raw mixture consisting of 43% imported ore fines and 40%45% domestic concentrate. Under the conditions of granulating moisture 6.5%, coke rate 5.5% and the basicity 1.8, the stumble index of the sinter was 60.53%,the productivity is 1.894t · m-2 · h-1 , the solid fuel exhaust was 54.07kg · t-1 , the FeO content was 8.99%, and the results of the conventional sintering process also indicates that with the increase of total iron content and the decrease of SiO2 content, the mechanical strength and yield of sinter decreases, and can't reach the demand of morden BF. So we have to develop new technique to meet with the development of our BF and to utilise raw material of our country.A new process-separated granulating sintering was developed in this article; i.e.concentrate fine and ore fines are granulated respectively first and then mixted. The ideal pesaudo-grain with low basicity core and high basicity shell is formed. Many parameters such as separated granulating duration moisture and proportioning ratio of burnt lime and basacity were researched to improve the granulation process and the correspondly separated of coke breeze was performed. It is shown that small size fraction in sintering blends is lowered by using this new technique, and the average size of blend is increased, the permeability of the sinter bed is improved. The result of this new process were as following: the stumble index of the sinter was 65%70%, the productivity is above 1.90 t·m-2 ·h-1 , the solid fuel exhaust was 51%-52kg · t-1, the FeO content was 8.2%8.8%. Compared with the conventional process, the stumble index of the sinter was increased by 10%, solid fuel exhaust was decreased by 3.6%4.8%, and the productivity of sinter is increased too. The FeO in the sinter was decreased obviously. The quality and the yield were greatly improved by this new technology. Pneumatics knetics of sintering process, thermodynamic and knetics of the formation of...
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