Variations on billet gas consumption intensity of reheating furnace in different production states

To achieve variations on billet gas consumption intensity (BGCI) of reheating furnace in different production states, a simplified BGCI apportionment model, which was based on the division of production states, was put forward in this paper. Firstly, production states were divided into four different modes according to the sequences of billet loading and unloading and billet number change in reheating furnace, namely, (i) normal production state (NPS), (ii) abnormal production state (APS), (iii) stop production state (SPS), which included preserving heat and waiting rolling state (PHWRS) and baking process state (BPS), (iv) transient production state (TPS), which included abnormal transient production state (ATPS) and stop transient production state (STPS). Secondly, a simplified BGCI apportionment model, which had better practicability, was established. Case study shown that the BGCI of APS or SPS was higher than that of NPS. And the longer the billet was in APS, the greater the BGCI was. Meanwhile, the initial temperature of billet and the repair time of reheating furnace had an important impact on BGCI. The results show that increasing the time of NPS is the most basic measurement in reducing BGCI. And elevation of initial temperature and reduction of the repair time are also effective measurement. And then, some suggestions and measures, which can achieve energy lean management of reheating furnace, are put forward.