Paper Title
HEAVY FUEL OIL COMBUSTION STUDY DURING INDUSTRIAL STEEL REHEATINGFOR THE CONTROLOF SCALE FORMATION

Abstract
Abstract - Based on the excessive formation of scale on steel during industrial reheating in the Libyan Iron and Steel Company's pusher type reheat furnaces, it was necessary to conduct studies in order to control this phenomenon. The formation of excessive amounts of scale presents some difficulties resulting from falling scale at the bottom of the furnace, accumulation at furnace site as well as steel lose. It is well known that higher percentages of free oxygen in the combustion products (higher than approximately 2%) promotes the formation of large quantities of oxides. and hence, this study aimed at reducing the free oxygen in the combustion products inside the furnace. Oxygen percentages in the furnace were measured during a normal furnace operation and were found to be between 4 and 6%. Using a long water-cooled steel pipe (designed and manufactured locally by the company) for the inhalation of in-furnace gases and using a Nova flue gas analyzer, combustion was adjusted in each of the five zones of the furnace, such that oxygen in the combustion products was lowered to approximately 2%. This was done by changing the air to fuel ratio in each of these zones. Accordingly, oxygen in the combustion product in the furnace was lowered to about 2.5%, a 60% reduction. Applying adjusted combustion air and fuel flow rates to the furnace operation resulted in lowering oxide scale formation. Keywords - Steel, Reheat Furnace, Combustion, Scale, Fuel Oil.