2020 Volume 60 Issue 11 Pages 2400-2407
Despite its many advantages, the materials layer with thickness exceeding 900 mm hinders further development of thick bed sintering. In order to break through the bottleneck of ultra-thick bed sintering, University of Science and Technology Beijing and Tiangang United Special Steel initiated a cooperation. Firstly, by analyzing the characteristics of the ultra-thick bed sintering, this study aims to make high air permeability and low air leakage rate the focus technically. Then a “triple sync” theory including the liquid phase front, heat transfer front and flame front and the concept of “Full Active Lime Intensified Sintering” were proposed to support thick bed sintering. On this basis, Tiangang United Special Steel develops a series of comprehensive technologies including raw materials controls, granulation enhancements and air leakage improvements, then efficient and stable sintering production with a bed height of 1000 mm in their two 260 m2 sintering machines is achieved. After the implementation of these technologies, the productivity reaches 1.89 t/(m2·h), the solid fuel consumption was only 41.85 kg/t, meanwhile the tumbler, reduction, and low-temperature reduction degradation index RDI+3.15 of produced sinter are 78.24%, 87.17%, and 74.2%, respectively. While promoting the development of ultra-thick bed sintering, it has also brought significant economic and environmental benefits.