SECONDARY COMBUSTION METHOD FOR CONVERTER STEEL MAKING METHOD OR MELT REDUCTION METHOD

摘要

PURPOSE:To improve the efficiency of combustion reaction and to efficiently add heat to a molten metal by disposing a lance provided with a nozzle hole slightly upper than the bottom end into a slag layer, supplying oxygen to the slag layer and burning the gaseous CO generated by the reaction. CONSTITUTION:The secondary combustion lance 5 and oxygen lance 9 for refining are positioned in the slag layer 3 of a furnace body 1. A gaseous oxygen passage 6 is provided to the central part of the above-mentioned lance 5 and a cooling water passage 7 is provided on the outside thereof. The nozzle hole 8 for blowing off the gaseous oxygen is formed slightly upper than the bottom end part in a horizontal direction. The nozzle hole 8 is preferably in a + or -10 deg. range in the horizontal direction and the number of the hole is =1 pieces. The slag layer 3 is stirred by the gaseous oxygen blown from the nozzle hole 8 and the gaseous CO existing in the slag layer 3 is burned by the oxygen rising from the molten metal 2. The high temp. generated by such combustion is held in the slag layer 3 and is efficiently applied to the molten metal 2.