| 摘要 |
PURPOSE:To enable reduction of production of NOx, by a method wherein a flame dispersion type nozzle is so formed as to be axially movable, and revolving vanes are mounted on the outer periphery of the nozzle, and a damper, regulating a ratio between primary and secondary air, is provided. CONSTITUTION:A radiant tube burner is axially moved within a set position L of a flame dispersion type nozzle 3 in a range of 100-500mm, and by fixing the burner by means of a set bolt 16, a combustion amount in primary combustion can be regulated and fixed. By regulating a ratio between primary and secondary air by means of a combustion air regulating damper 7, an NOx production amount can bring the burner into an optimum combustion state. Revolving vanes 10 are mounted on the nozzle 3 to generate a swirl flow, and this constitution enables a difference between a maximum and a minimum temperature to be adjusted in a range within 10 deg.C and 150 deg.C in a peripheral and an axial direction respectively in relation to the temperature of a tube. Since a maximum tube temperature at a time when temperature in a furnace is 950 deg.C is 1,050 deg.C or less, the life of the radiant tube can be increased to a value durable to a long-term use.
|
