DETECTING METHOD FOR RUPTURE OF BOILER TUBE FOR COKE DRY TYPE FIRE EXTINGUISHING INSTALLATION

摘要

PURPOSE:To reliably detect the rupture of a boiler tube by a method wherein the concentration of hydrogen gas and CO gas and a pressure in prechamber are placed under supervision. CONSTITUTION:A measuring signal for pressure in a chamber 15 detected by a pressure oscillator 31 and a measuring signal for concentration of hydrogen gas and CO gas in cooling gas detected by a gas analyzer 32 are inputted to a computing device 33 and are compared with a reset reference value for computation. When it is confirmed that measuring values exceed their respective reference values, a time after elapse of 12min starting from this confirmation is decided to be the boiler tube's rupture detecting timing. Since hydrogen gas and CO gas generated from uncarbonized coke are mixed in cooling gas and there is a fear of erroneous detection being effected due to an increase in a pressure in the prechamber, a flow rate signal from a steam flow meter 36 mounted in a steam feed pipe 28 and a stem flow meter 37 mounted in a steam feed pipe 29 running to a deaerator 22 are added to the computing device 33. By comparing the adding result with a feed flow rate of a feed flow meter 35 mounted in a feed pipe 27 of a waste heat boiler 12, unbalance therebetween is detected and added, and detection of the rupture of the boiler tube is performed.