| Popis: |
Aiming at the problem of low efficiency in high bed sintering, a new process, namely double layer pre-sintering was developed by AISC Iron and Steel Research Institute. The new process can obviously improve the bed permeability and sintering productivity with a large proportion of fine iron concentrate. However, the cold strength of sinter for the new process decreases to a certain extent, which is mainly caused by the lack of oxygen in the lower sintering layer. At present, by properly prolonging the pre-sintering time, the oxygen deficiency in the lower sintering layer can be alleviated to a certain extent, and the cold strength of sinter can be significantly improved. The industrial test results of 360 m2 sintering machine in No. 2 sintering workshop and the No. 4 and No. 5 blast furnaces of Iron-making Plant of Angang Steel Co. Ltd for nearly 7 months show that the new double layer pre-sintering process is completely feasible in production practice, and 16.11% of the sintering output has been achieved. The blast furnace runs smoothly with the sinter of double layer pre-sintering process. Furnace productivity, fuel ratio and air volume are basically consistent with the reference period. The implementation of this new process is the first case in China. However, the new process needs to be further improved in order to achieve the best sintering output, reduce sinter solid fuel consumption and emission of nitrogen oxides and carbon oxides. |
