| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of cooling an air preheater in a heating furnace, configured to prevent melting damage of the air preheater by supplying cooling air sufficient for the air preheater, even when an operating state of the heating furnace changes, in the heating furnace including a regenerative burner and a continuous combustion burner.SOLUTION: The air preheater 31 is cooled by discharging a heat-exchanged combustion exhaust gas discharged from the regenerative burner 11, to a flue 30 of an air preheater outlet side 31b, and allowing the combustion air supplied to the continuous combustion burner 12 to pass through the air preheater 31, in the heating furnace 10 including the regenerative burner 11 and the continuous combustion burner 12.In the cooling method, an amount of cooling air A0 necessary for cooling the air preheater 31 to its heatproof temperature or less, is calculated from an amount of combustion exhaust gas passing through the air preheater 31 and a combustion exhaust gas temperature of an air preheater inlet side 31a, and the combustion air preheated by the air preheater 31 is partially diffused to the atmosphere, when an actual measurement value A1 of the amount of combustion air supplied to the continuous combustion burner 12 is less than the amount of cooling air A0. |
