| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for preventing the corrosion of an exhaust gas cooler by which the corrosion of an exhaust gas cooler part is prevented by reducing NOx concentration incorporated in the exhaust gas at the preheating time with a simple structure, thereby reducing the maintenance cost of the exhaust gas cooler and extending the service life. SOLUTION: An exhaust gas duct 12 is constituted of; a first horizontal part 12a whose one end is connected to the upper part of a vacuum-degassing vessel 10; an inclining part 12b whose one end is connected to another end of the first horizontal part 12a and which inclines in slanting lower part; and a second horizontal part 12c whose one end is connected to another end of the inclining part 12b and whose another end is connected to the exhaust gas cooler 11. A connection part between the first horizontal part 12a and the inclining part 12b is made to be a first bending part P1 having the bending angleα1 to the horizontal surface, and the connecting part of the inclining part 12b and the second horizontal part 12c, is made into a second bending part P2 having the bending angleα2 to the horizontal surface. Level difference D of the bending, is made to be≥1.0 and <4.0 times of the inner diameter of the first horizontal part 12a, and the bending anglesα1,α2, are defined as <45°. COPYRIGHT: (C)2010,JPO&INPIT |
