Application of Numerical Model for Blast Furnace Taphole Opening Operation to Individual Phenomena

摘要

Molten iron and slag produced in blast furnace are drained through a taphole simultaneously, and the drainage is generally referred to as tapping. A taphole, of which typical geometrical dimension is 3 to 4 m in length and 50 to 60 mm in diameter, is plugged by monolithic refractory, called taphole mix. Tapping starts from the taphole opening that is carried out by drilling the taphole mix-plugged taphole. Total time from the start of drilling to the end of penetration (taphole opening time) usually takes 5 to 15 minutes, depending on taphole mix properties as well as drilling equipment performance1 3). New drills are applied into each taphole opening operation since in-furnace end of drills tends to immerse in molten iron and slag in blast furnace hearth.