| 摘要 |
PURPOSE:To lower the amount of NOx produced at the time when a boiler is started to the same level as that at the time when it is operated stably, by allowing the combustion gas to be recycled by a fan from the time when the boiler is started. CONSTITUTION:A steam coil type air heater 19 having a heating pipe 20 therein for heating the air taken from a fan 12 is provided between the fan 12 and an air heater 11, an apparatus wherein an inlet damper 16 for an idle burner 15 and a wind box partition 18 is kept in an airtight relation is used, and the combustion gas is supplied to the idle burner 15 through a separate exclusive duct for preventing the burnout. After completion of the purge, the recycle system for the combustion gas is started, and then the ignition is effected. At the same time of the start of the recycle system for the combustion gas, auxiliary steam from another boiler is passed to the heating pipe 20 so that the temperature of the combustion gas is raised to 100 deg.C or above quickly. |
