PREVENTING METHOD OF ABNORMAL DECREASE OF PRESSURE IN CONVERTER OF CONVERTER WASTE GAS TREATING DEVICE

摘要

PURPOSE:To prevent the abnormal decrease of the pressure in a converter by operating the converter while maintaining nearly the hermetic state between the port and skirt part of the converter and returning a part of the recovered waste gas to the skirt part via a duct when the pressure in the furnace drops abnormally. CONSTITUTION:A molten iron 2 is subjected to blowing while nearly the hermetic state is maintained between the port and skirt part 4 of a converter 1. The waste gas generated by the blowing is sucked by an induced draft fan 11 into a diffusing chimney 13 and holder. A gas return duct 16 communicating with the upper part of the skirt part 4 is provided behind a recovering valve 14 so that a part of the waste gas is returned via shut-off valves 17-1, 17-2. The pressure in the converter is detected by a transmitter 5 for the pressure in the converter and when the pressure decreases to a prescribed value or below, a gas return control device 18 opens successively the valves 17-1, 17-2 to return a part of the recovered waste gas to the skirt part 4 via a duct 16 thereby restoring the normal pressure in the converter.