고로 냉각반 설계에 대한 엔지니어링 연구

Abstract

This study introduces the feasibility of newly designed board type cooling plate of blast furnace. To increase the production of blast furnace, copper stave has been widely used for cooling system, but the problem of abrasion affected to change the type from copper stave to cooling plate. Cooling plate is easy to replace when it is damaged, but once the refractories around the cooling plate disappears after a few years of operation, cooling capacity decrease dramatically and it causes the decrease of blast furnace’s life. To solve this problem, POSCO designed board type cooling plate, which the width of cooling plate is longer than the original design. It is assumed that the newly designed cooling plate has improved cooling capacity and it is easy to form the skull, which is the accretion around the cooling plate to protect itself from chemical and mechanical wear. Since the board type cooling plate is not installed in real blast furnace, it needs to be evaluated the feasibility in 4 ways. Firstly, newly design needs to have improved cooling capacity and reasonable cooling conditions. Secondly, steel shell which support the cooling plate has to be stable, and the gap between cooling plates has to be sufficient against thermal expansion. Thirdly, skull has to be performed properly to protect the cooling plate. Lastly, the gas flow of blast furnace wall has to be stabilized. To solve this problem, analyzing optimal heat transfer, thermal stress, material behavior and gas flow was examined. The results show newly designed cooling plate has improved cooling capacity, and the reasonable cooling condition proposed. The support of steel shell is also stable and the sufficient gap between the cooling plates also proposed. The main factor affecting the formation of skull revealed and the gas flow of blast furnace wall is stable. Overall, the newly designed cooling plate is superior to the original design and it is proper for installing to blast furnace.