PREDICTION OF BLAST FURNACE HEARTH CONDITION: THEORY AND PRACTICE

摘要

In a modern blast furnace (BF) operation, the hearth is a critical zone influencing both the routine casting performance and campaign life. In practice, the refractory temperature distribution is a valuable measurement for assessing the hearth condition. However, whether for normal BF operations or very long maintenance shutdowns, the refractory temperature cannot fully provide a comprehensive understanding of the hearth condition. In this regard, mathematical and numerical modelling, often coupled with physical modelling, has played an important role in interpreting these temperature distributions. One aspect of the present investigation involved using an improved conjugate-heat transfer model to describe the flow of liquid iron coupled with liquid-refractory heat transfer in the hearth of BlueScope's Port Kembla No. 5 Blast Furnace (BF5) under normal operating conditions. Another aspect involved the development and application of a new transient numerical model to simulate hearth cooling during an extended maintenance shutdown period. The outcomes from both activities proved to be a useful guide for furnace and maintenance engineers.